S-1

As filed with the Securities and Exchange Commission on April 28, 2014

Registration No. 333-            

UNITED STATES SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

Aspen Aerogels, Inc.

(Exact name of Registrant as specified in its charter)

Delaware	3990	04-3559972
(State or other jurisdiction of incorporation or organization)	(Primary Standard Industrial Classification Code Number)	(I.R.S. Employer Identification Number)

30 Forbes Road, Building B

Northborough, Massachusetts 01532

(508) 691-1111

(Address, including zip code, and telephone number, including area code, of Registrant’s principal executive offices)

Donald R. Young

President and Chief Executive Officer

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, Massachusetts 01532

(508) 691-1111

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Sahir Surmeli, Esq. Thomas R. Burton, III, Esq. John T. Rudy, Esq. Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. One Financial Center Boston, Massachusetts 02111 (617) 542-6000 John F. Fairbanks Vice President, Chief Financial Officer and Treasurer Aspen Aerogels, Inc. 30 Forbes Road, Building B Northborough, Massachusetts 01532 (508) 691-1111 Roxane F. Reardon, Esq. Simpson Thacher & Bartlett LLP 425 Lexington Avenue New York, New York 10017 (212) 455-2000

Approximate date of commencement of proposed sale to the public: As soon as practicable after this registration statement becomes effective.

If any of the securities being registered on this form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933 as amended (the “Securities Act”), check the following box.      ¨

If this form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.      ¨

If this form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.      ¨

If this form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.      ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer  ¨	Accelerated filer  ¨	Non-accelerated filer  þ	Smaller reporting company  ¨
		(Do not check if a smaller reporting company)

CALCULATION OF REGISTRATION FEE

Title of Each Class of Securities to be Registered	Proposed Maximum Aggregate Offering Price(1)(2)	Amount of Registration Fee(2)
Common Stock, $0.00001 par value per share	$86,250,000	$11,109

(1) Estimated solely for the purpose of computing the amount of the registration fee pursuant to Rule 457(o) under the Securities Act of 1933, as amended.

(2) Includes the offering price of shares of common stock that may be sold if the over-allotment option granted by the Registrant to the underwriters is exercised.

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the Registration Statement shall become effective on such date as the Securities and Exchange Commission, acting pursuant to said Section 8(a), may determine.

The information in this preliminary prospectus is not complete and may be changed. These securities may not be sold until the registration statement filed with the Securities and Exchange Commission is effective. This preliminary prospectus is not an offer to sell nor does it seek an offer to buy these securities in any jurisdiction where the offer or sale is not permitted.

Subject to Completion, dated April 28, 2014

PROSPECTUS

             Shares

Aspen Aerogels, Inc.

Common Stock

This is the initial public offering of shares of common stock of Aspen Aerogels, Inc.

We are offering              shares of common stock. No public market currently exists for our common stock.

We intend to apply to list the common stock on the New York Stock Exchange under the symbol “ASPN.”

We anticipate that the initial public offering price will be between $         and $             per share.

We are an “emerging growth company” as that term is used in the Jumpstart Our Business Startups Act of 2012 and, as such, have elected to comply with certain reduced public company reporting requirements for this prospectus and future filings.

Investing in our common stock involves risks. See “Risk Factors” beginning on page 14 of this prospectus. 

	Per Share	Total
Initial public offering price	$	$
Underwriting discounts and commissions(1)	$	$
Proceeds, before expenses, to us	$	$

(1) We have agreed to reimburse the underwriters for certain expenses in connection with this offering. See “Underwriting.”

To the extent that the underwriters sell more than              shares of common stock, the underwriters have the option to purchase up to an additional              shares from us at the initial public offering price less the underwriting discount.

Neither the Securities and Exchange Commission nor any other regulatory body has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus. Any representation to the contrary is a criminal offense.

The underwriters expect to deliver the shares on or about                     , 2014.

Barclays J.P. Morgan Citigroup

Prospectus dated                     , 2014

TABLE OF CONTENTS

	Page
PROSPECTUS SUMMARY		1
RISK FACTORS		14
SPECIAL NOTE REGARDING FORWARD LOOKING STATEMENTS		39
USE OF PROCEEDS		41
DIVIDEND POLICY		42
CAPITALIZATION		43
DILUTION		45
SELECTED CONSOLIDATED FINANCIAL DATA		47
MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS		50
BUSINESS		83
MANAGEMENT		106
EXECUTIVE AND DIRECTOR COMPENSATION		114
CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS		128
PRINCIPAL STOCKHOLDERS		134
DESCRIPTION OF CAPITAL STOCK		140
DESCRIPTION OF CERTAIN INDEBTEDNESS		146
SHARES ELIGIBLE FOR FUTURE SALE		149
MATERIAL U.S. FEDERAL TAX CONSIDERATIONS FOR NON-U.S. HOLDERS		152
UNDERWRITING		156
LEGAL MATTERS		163
EXPERTS		163
WHERE YOU CAN FIND MORE INFORMATION		163
INDEX TO CONSOLIDATED FINANCIAL STATEMENTS		F-1
APPENDIX A — GLOSSARY OF SELECTED TERMS		A-1

No dealer, salesperson or other person is authorized to give any information or to represent anything not contained in this prospectus. You must not rely on any unauthorized information or representations. This prospectus is an offer to sell only the shares offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so.

INDUSTRY AND MARKET DATA

This prospectus contains market data and industry forecasts that were obtained from industry publications, third party market research and publicly available information. These publications generally state that the information contained therein has been obtained from sources believed to be reliable, but the accuracy and completeness of such information is not guaranteed.

This prospectus also contains estimates and other statistical data made by independent parties and by us relating to market size and growth, size of insulation opportunity at various types of energy infrastructure facilities and other data about our industry. We obtained the industry and market data in this prospectus from our own research as well as from industry and general publications, surveys and studies conducted by third parties, some of which may not be publicly available. For example, this prospectus also includes statistical data extracted from an off-the-shelf market research report (World Insulation - #2956) by The Freedonia Group, an independent international market research firm, and a separate custom market research report by Freedonia Custom Research, Inc., a wholly-owned subsidiary of The Freedonia Group, or Freedonia, which was commissioned by us and was issued in February 2014. Such data involves a number of assumptions and limitations and contains projections

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and estimates of the future performance of the industries in which we operate that are subject to a high degree of uncertainty. We caution you not to give undue weight to such projections, assumptions and estimates.

The Freedonia Custom Research, Inc. Report, or the Freedonia Report, represents data, research opinion or viewpoints developed independently on our behalf and does not constitute a specific guide to action. In preparing the Freedonia Report, Freedonia used various sources, including publicly available third party financial statements; government statistical reports; press releases; industry magazines; and interviews with manufacturers of related products (including us), manufacturers of competitive products, distributors of related products and government and trade associations. The Freedonia Report speaks as of its final publication date (and not as of the date of this prospectus).

Information about End-Use Customers

The data and statistics that we present relating to the end-users of our products, such as our sales to owners and operators of refineries, petrochemical plants, LNG facilities, power generating assets and other energy infrastructure facilities, are estimates based on our reasonable belief. This is because we sell our products primarily to distributors, contractors and OEMs that in turn sell our products to end-users or install our products into the facilities or equipment of the ultimate end-users. Consequently, the information that we derive from our sales process and our invoice process to our direct distributors, contractors and OEM customers typically does not indicate with certainty into which end market the product will be used or for what purpose. We base our estimates on information obtained from: (i) discussions with and feedback received from our direct distributor, contractor and OEM customers that purchase directly from us, (ii) discussions with and feedback received from our end-users, and (iii) the nature and potential uses of each of our products, as certain of our products are designed for use in a specific market.

TRADEMARKS, TRADE NAMES AND SERVICE MARKS

We own or have rights to use “Aspen Aerogels,” “Cryogel,” “Pyrogel,” “Spaceloft,” the Aspen Aerogels logo and other trademarks, service marks and trade names of Aspen Aerogels appearing in this prospectus. Solely for convenience, the trademarks, service marks and trade names referred to in this prospectus are without the ^® and ^TM symbols, but such references are not intended to indicate, in any way, that the owner thereof will not assert, to the fullest extent under applicable law, such owner’s rights to these trademarks, service marks and trade names. This prospectus contains additional trademarks, service marks and trade names of other companies, which, to our knowledge, are the property of their respective owners.

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PROSPECTUS SUMMARY

This summary provides an overview of selected information contained elsewhere in this prospectus and does not contain all of the information you should consider before investing in our common stock. You should carefully read this prospectus and the registration statement of which this prospectus is a part in their entirety before investing in our common stock, including the information discussed under “Risk Factors” and our consolidated financial statements and the related notes thereto included elsewhere in this prospectus. A glossary of selected terms is provided in Appendix A located at the end of this prospectus. Unless otherwise indicated herein, the terms “we,” “our,” “us,” or “the Company” refer to Aspen Aerogels, Inc. and its predecessor entity and unless otherwise noted, their respective subsidiaries.

Overview

We are an energy technology company that designs, develops and manufactures innovative, high-performance aerogel insulation used primarily in large-scale energy infrastructure facilities. We believe our aerogel blankets deliver the best thermal performance of any widely used insulation product available on the market today and provide a combination of performance attributes unmatched by traditional insulation materials. Our products provide two to five times the thermal performance of widely used traditional insulation in a thin, easy-to-use and durable blanket form. Our end-use customers select our products where thermal performance is critical, and to save money, reduce energy use, preserve operating assets and protect workers.

Our technologically advanced products are targeted at the estimated $2.8 billion annual global market for energy infrastructure insulation materials. Our aerogel insulation has undergone rigorous technical validation and is used by many of the world’s largest oil producers and the owners and operators of refineries, petrochemical plants, liquefied natural gas, or LNG, facilities and power generating assets, such as ExxonMobil, Formosa Petrochemical, Pemex Gas and NextEra Energy Resources. Our products replace traditional insulation in existing facilities during regular maintenance, upgrades and capacity expansions. In addition, we are increasingly being specified for use in new-build energy infrastructure facilities.

We introduced our two key product lines, Pyrogel and Cryogel, in 2008. We have invested significant resources to commercialize our technology and to build our business, have incurred and expect to continue to incur annual operating losses, and have an accumulated deficit of $332.8 million at December 31, 2013. As a result of this investment, our product revenue has grown from $17.2 million in 2008 to $82.1 million in 2013, representing a compound annual growth rate of 37%. We have sold more than $250 million of our products globally, representing an installed base of more than 100 million square feet of insulation. We believe that this initial success positions us for future growth and continued gain in market share.

We currently target our sales efforts in the energy infrastructure market, where we believe our products have the highest value applications. As we continue to expand our production capacity and enhance our technology, we believe we will have opportunities to address additional high value applications in the estimated $37 billion global insulation market.

Aerogels are complex structures in which 97% of the volume consists of air trapped between intertwined clusters of amorphous silica solids. These extremely low density solids provide superior insulating properties. Our products enable compact design, reduce installation time and costs, promote freight and logistics cost savings, reduce system weight and required storage space and enhance job site safety. Our products reduce the incidence of corrosion under insulation, which is a significant maintenance cost and safety issue in energy infrastructure facilities. Our products also offer strong fire protection, which is a critical performance requirement in our markets. We believe our array of product attributes provides strong competitive advantages over traditional insulation. Although competing insulation materials may have one or more comparable attributes, we believe that no single insulation material currently available offers all of the properties of our aerogel insulation.

We manufacture our products using proprietary technology at our facility in East Providence, Rhode Island. We have operated the East Providence facility at high volume and high yield since 2008. We successfully

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commenced operation of our second production line at this facility at the end of March 2011, which doubled our annual nameplate capacity to 40 million to 44 million square feet of aerogel blankets, depending on product mix.

To address anticipated near and mid-term capacity constraints caused by increasing demand for our products, we are in the process of expanding our production facility. We are in the design and engineering phase of a third production line at our East Providence facility and have procured certain capital equipment with a longer lead-time. We currently expect that this third line will increase our annual nameplate capacity by 25% to 50 million to 55 million square feet and will be completed in the first half of 2015. We plan to construct a second manufacturing facility in Europe or Asia, the location of which will be based on factors including labor and construction costs, availability of governmental incentives, and proximity to raw material suppliers. We anticipate initial operation of a first production line at this facility during 2017.

Our capacity expansion plan requires us to raise capital. We plan to complete the expansion of our current production facility using a portion of the proceeds from this offering. We will use additional proceeds from this offering to fund the development, design and a portion of the build-out of a second plant. We expect to utilize anticipated cash flows from operations, local government grants and debt financing to provide the remaining capital required to complete the first production line in our second facility.

Our Core Market

Our two principal products, Pyrogel and Cryogel, are used by many of the world’s largest oil producers, refiners and petrochemical companies. Our products are also in use in applications in a variety of other energy infrastructure facilities around the world, including LNG facilities, oil sands extraction operations, offshore oil projects and power generation facilities. Insulation systems in these markets are designed to maintain hot and cold process piping and storage tanks at optimal process temperatures, to protect plant and equipment from the elements and from the risk of fire, to mitigate corrosion and to protect workers. Insulation is low in cost relative to the total cost of a typical energy infrastructure facility, but is critical to its safe, reliable and efficient operation. According to estimates in the Freedonia Custom Research Inc. Report, or the Freedonia Report, the worldwide energy infrastructure insulation market totaled $2.8 billion in 2013 and is expected to grow to $3.5 billion in 2018. We estimate that we generated 87% of our 2013 product revenue in the energy infrastructure insulation market.

Global energy demand for all forms of energy is expected to increase by 56% from 2010 to 2040, according to the International Energy Outlook 2013 report by the U.S. Energy Information Administration, or EIA. In order to serve this growing demand, we believe our end-use customers will continue to invest in major energy infrastructure projects. The major end markets that drive demand for our products include:

• Oil Refining: We believe our aerogel blankets are used by 24 of the world’s largest 25 refining companies including ExxonMobil, Petrobras and Chevron, among others. World refining capacity is projected to increase by approximately 1.5 million barrels of crude oil, condensate or natural gas liquids per day (MMBbl/d) on average per year from 2013 to 2017, according to the September 2013 Barclays CEO Energy-Power Conference presentation by Valero Energy Corporation.

• Petrochemical: We believe our aerogel blankets are used by 19 of the world’s 20 largest petrochemical companies including Formosa Petrochemical, Hu-Chems Company and a major Asian energy company, among others. Worldwide capital spending in the chemistry sector is projected to increase from $413.8 billion in 2012 to $617.5 billion in 2018, at a compound annual growth rate of 6.9%, according to the Year-End 2013 Chemical Industry Situation and Outlook report by the American Chemistry Council, America’s oldest chemicals trade association.

• Natural Gas and LNG: Our products are in use at ExxonMobil, Pemex Gas and Qatargas, among others. As of March 2014, global LNG demand is expected to increase from 28.8 billion cubic feet of natural gas per day (Bcf/d) in 2010 to 60.1 Bcf/d in 2025, at a compound annual growth rate of 5.0%, according to the Global LNG Long-Term Outlook Q1 2014 by Wood Mackenzie, a leading independent energy research and consulting firm.

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• Onshore Oil Production, including Oil Sands: Our aerogel blankets are in use in several Canadian oil sands facilities owned and operated by Suncor Energy, ConocoPhillips and Husky Energy, among others. Annual production from oil sands activities is projected to increase from 1.8 MMBbl/d in 2012 to 5.2 MMBbl/d in 2030, at a compound annual growth rate of 6.1%, according to the June 2013 Crude Oil Forecasts, Markets & Transportation report by the Canadian Association of Petroleum Producers.

• Offshore Oil Production: Our products are currently used in subsea projects off the coast of Brazil, in the Gulf of Mexico, in the North Sea, off the coast of Malaysia and off the west coast of Africa in projects operated by Marathon Oil, ConocoPhillips, Shell and others. Our relationships with Technip and other engineering, procurement and construction contractors are critical to the selection of our products for subsea projects. Annual global spending on offshore drilling activities is projected to increase from $97 billion in 2012 to $170 billion in 2019, at a compound annual growth rate of approximately 8.4%, according to the December 2013 Drilling and Production Outlook report by Spears and Associates, Inc., a leading independent oilfield equipment and service company research and consulting firm.

• Power Generation: We are targeting operators of gas, coal, nuclear, hydro and solar power generating facilities. Although not a significant portion of our revenue today, our products are currently used at a facility owned and operated by NextEra Energy Resources among other power generation facilities. Global net electricity generation is projected to increase by 69% from 21.4 trillion kilowatt hours, or kWh, in 2012 to 36.2 trillion kWh in 2035, according to the International Energy Outlook 2013 report by the EIA.

We are targeting continued expansion of the use of our products within energy infrastructure facilities during regular maintenance, upgrades and expansions. In addition to opportunities to replace traditional insulation at existing facilities, we are also pursuing insulation applications at new-build and large capacity expansion projects around the world. Historically, a significant portion of our revenue has been derived from displacing traditional insulation at existing facilities, in particular during periods of planned plant maintenance or upgrades. We believe these maintenance applications will continue to comprise a large portion of our revenue mix. As our end-use customers gain experience with our products at existing facilities, we believe that more of our customers will also select our products for new-build facility construction and large capacity expansion projects, which we expect to drive significant revenue growth.

We also derived 13% of our 2013 product revenue from the building and construction and other end markets. Customers in these markets use our aerogels for applications as diverse as wall systems, military and commercial aircraft, trains, buses, appliances, apparel, footwear and outdoor gear. While not our core market, we anticipate that we will continue to allocate a modest portion of our manufacturing capacity to serve these markets.

In addition, we continue to perform contract research services for a number of federal and non-federal government agencies, including NASA, National Science Foundation, Defense Advanced Research Projects Agency, U.S. Army, U.S. Navy, U.S. Air Force and the Department of Energy, among others.

Our Solution

We believe our aerogel blankets deliver a superior combination of performance attributes that enable end-users to save money, reduce energy use, preserve operating assets and protect workers across a wide range of applications in our target markets, including:

• Best Thermal Performance. Our aerogel blankets provide the best thermal performance of any widely used insulation product available on the market today and excel in applications where thermal performance requirements are demanding or available space for insulation is constrained. Our products address a wide range of applications within the cryogenic and sub-ambient (down to -200°C), ambient and hot process (up to 650°C) temperature ranges.

• Reduced Corrosion Under Insulation, or CUI. Our Pyrogel XT product line is both hydrophobic and vapor permeable. These attributes have the potential to reduce the incidence of CUI in hot process

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applications, which we believe provides our end-users with a significant reduction in long-term operating and capital costs. Corrosion of process piping and storage tanks increases the risk of catastrophic system failures. Preventative facility maintenance and related expenses are estimated to cost the petrochemical industry billions of dollars per year. Our products also offer improved thermal performance in insulation systems exposed to the elements or operating in humid environments compared to traditional insulation.

• Compact Design and Faster Installation. Our aerogel blankets reduce insulation system volume by 50% to 80% compared to traditional insulation, enabling a reduction in the footprint, size and structural costs of complex facilities. The flexible form factor of our products also makes them faster to install than rigid insulation materials, which reduces labor costs and total installed costs. In addition, our products reduce the volume and weight of material purchased, inventoried, transported and installed in the field, and they reduce the number of stock-keeping units required to complete a project. Simplified logistics accelerate project timelines, reduce installation costs and protect workers.

• High Durability and Fire Protection. Our aerogel blankets offer excellent compression resistance, tensile strength and vibration resiliency. Our products allow companies to pre-insulate, stack and transport steel pipes destined for use in harsh environments, which significantly reduces installation labor costs in remote areas. In addition, our Pyrogel XTF product was specifically designed to provide strong fire performance in applications within the energy infrastructure and other end markets.

We believe these product attributes uniquely address the demanding performance requirements of the energy infrastructure insulation market. In particular, these attributes help our end-use customers reduce long-term operating and capital costs and meet their goals to enhance safety and reliability. We believe these characteristics are leading our end-use customers to choose our insulation products in a growing number of energy infrastructure facilities.

Our Competitive Strengths

We believe the following combination of capabilities distinguishes us from our competitors and positions us to continue to gain market share in the energy infrastructure insulation market:

• Disruptive Products with a Compelling Value Proposition. Our aerogel products provide two to five times the thermal performance of widely used traditional insulation in a thin, easy-to-use and durable blanket form. We believe our array of product attributes provides strong competitive advantages over traditional insulation and will enable us to gain a larger share of the energy infrastructure insulation market. Although competing insulation materials may have one or more comparable attributes, we believe that no single insulation material currently available offers all of the properties of our aerogel insulation.

• Attractive Energy End Markets. Our products are primarily used in large scale energy infrastructure facilities. Freedonia has estimated that the worldwide energy infrastructure insulation market totaled $2.8 billion in 2013 and is expected to grow to $3.5 billion by 2018. Global energy demand for all forms of energy is expected to increase by 56% from 2010 to 2040, according to the International Energy Outlook 2013 report by the EIA. Given the continued growth in global energy consumption and the construction of new facilities to satisfy this demand, we believe that we serve attractive and growing global end markets. In order to capture the opportunities in our end markets, we have a network of sales professionals and qualified distributors in more than 30 countries around the world.

• Growing Installed Base with Industry-leading End-Users. We have an installed base of more than 100 million square feet of insulation, representing more than $250 million in cumulative product sales since 2008. Through our relationships with industry leading end-use customers, our products have undergone rigorous testing and technical validation and are now in use at many of the world’s largest oil

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producers, refiners and petrochemical companies. These relationships have shortened the sales cycle with other customers and have helped to facilitate our market penetration. We also have strong relationships with a global network of energy-focused distributors, contractors and engineering firms that understands the significant advantages our products provide to end-users. We believe our products have been used by 24 of the world’s largest 25 refining companies and 19 of the world’s largest 20 petrochemical companies and have been initially deployed in approximately 30% of the world’s 640 refineries.

• Proven, Scalable Business Model. Our proprietary manufacturing technology is proven and has been successfully scaled up to meet increasing demand. We have operated the East Providence facility at high volume and high yield since 2008. We successfully commenced operation of our second production line at this facility in March 2011 and doubled our annual nameplate capacity to 40 million to 44 million square feet of aerogel blankets.

• Protected Technology Platform and Proprietary Manufacturing Capability. Our product solution is the result of more than a dozen years of research and development dedicated to new aerogel compositions, form factors and manufacturing technologies. Our intellectual property portfolio is supported by 51 issued patents, with an additional 18 pending in U.S. and foreign jurisdictions in areas related to product design, chemistry, process technology and market applications. In addition, we believe we have significant trade secrets related to product formulations and manufacturing techniques. We believe our portfolio of patents, trade secrets and know-how presents a formidable barrier to potential new entrants in the production of aerogel blanket insulation.

• Experienced Management Team with a Demonstrated Track Record. Our executive officers have an average of more than 20 years each of experience in global industrial companies, specialty chemical companies or related material science research. This management team is responsible for the development of our proprietary manufacturing technology, the commercial acceptance of our products, and the creation of a global distribution and marketing platform. As of April 15, 2014, we employed 220 research scientists, engineers, manufacturing line operators, sales and administrative staff, and management. We believe our dedicated and experienced team is an important competitive asset. Our senior management team and key employees will continue to have a significant equity stake in Aspen Aerogels following this offering.

Our Growth Strategy

Our strategy is to create shareholder value by becoming the leading provider of high-performance insulation products serving global energy infrastructure customers. Key elements of our strategy include:

• Expand Our Manufacturing Capacity to Meet Market Demand. Demand for our aerogel products has grown significantly. From 2008 through 2013, our product revenue has grown at a compound annual growth rate of 37% to $82.1 million. To meet anticipated growth in demand for our products, we are engaged in the design, engineering and procurement phases of a third production line in our East Providence facility and plan to construct a second manufacturing facility in Europe or Asia. We expect that this third production line at our East Providence facility will increase our annual nameplate capacity by 10 million to 11 million square feet of aerogel blankets at a total additional construction cost of approximately $30 million. We expect this third production line to be completed in the first half of 2015. We also intend to build a second production plant in Europe or Asia after completion of our third production line. We anticipate initial operation of the first production line at this facility during 2017. Based on our preliminary plans for this plant, our projected cost to construct this first production line and plant infrastructure for a multi-line facility is $80 million to $100 million with an estimated annual nameplate capacity of 26 million to 28 million square feet of aerogel blankets. The plant infrastructure design would also support future development of two additional similar production lines.

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• Increase Our Market Share. We plan to focus additional resources to continue to grow our share of the energy infrastructure insulation market, both through increased sales to our existing customers and through sales to new customers. We will continue to expand our global sales force and distribution network in support of this objective and seek to promote greater enterprise-wide utilization of our products by existing end-use customers. To date, the majority of our revenue has been generated from applications in refineries and petrochemical facilities. We will continue to pursue and expect greater adoption of our products in the oil production, LNG production and storage, and power generation markets.

• Exploit Project Growth Opportunities. Our product revenue has been and will be generated in large part by demand for insulation associated with scheduled plant shutdowns, or turnarounds, and other maintenance-related projects. With our broad adoption and growing installed base, we expect that our products will be specified during the design phase in a growing number of new plant construction and capital expansion projects. We expect that growth in global energy demand will result in increased new-build and large capacity expansion projects, driving demand for our aerogel products.

• Continue to Improve Our Profit Margins. We will continuously improve the cost efficiency of our manufacturing process to optimize the formulation of our products and to manage our supply chain to reduce costs. In addition, we plan to establish our second facility in a lower-cost labor market. As our overall manufacturing scale grows, we believe there will be additional opportunities to realize efficiencies and to reduce our per unit overhead costs. We believe our current expansion plan offers attractive returns on incremental invested capital.

• Capitalize on Innovation. We employ a team of research scientists and process engineers focused on advancing our current aerogel technology and developing next generation aerogel compositions, form factors and manufacturing processes. We believe that we are well positioned to leverage a decade’s worth of research and development to design and commercialize additional disruptive aerogel products for the energy infrastructure market. In addition, as we continue to enhance our technology and expand our capacity, we believe we will have opportunities to address additional high value applications in the estimated $37 billion global insulation market.

Risks Related to Our Business

Investing in our common stock involves substantial risk. You should carefully consider all of the information in this prospectus prior to investing in our common stock. There are several risks related to our business that are described under “Risk Factors” elsewhere in this prospectus. Among these important risks are the following:

• We have incurred net losses since our inception, and we may continue to incur net losses in the future and may never reach profitability;

• We have yet to achieve positive cash flow, and our ability to generate positive cash flow is uncertain;

• Our independent registered public accounting firm’s report contains an explanatory paragraph that expresses substantial doubt about our ability to continue as a going concern;

• We are dependent on a sole manufacturing facility. Any significant disruption to this facility or the failure of either of our two production lines in this facility to operate according to our expectation could have a material adverse effect on our business and our results of operations;

• If we fail to achieve the increase in production capacity that our continued growth requires, our growth may be hindered and our business may be materially adversely affected;

• If the expected growth in the demand of our products does not follow each of our planned capacity expansions, then our business will be materially adversely affected;

• We will require significant additional capital to pursue our growth strategy beyond the construction of our third line in our East Providence facility, but we may not be able to obtain additional financing on acceptable terms or at all;

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• The market for insulation products incorporating aerogel blankets is relatively undeveloped and our products may never be widely adopted, which would have a material adverse effect on our business;

• Our products are expensive relative to other insulation products, which could make it more difficult for us to grow our revenue and achieve broader adoption of our aerogel products;

• Our directors, officers and principal stockholders have significant voting power and may take actions that may not be in the best interests of our other stockholders; and

• Our inability to protect our intellectual property rights could negatively affect our business and results of operations.

Implications of Being an Emerging Growth Company

As a company with less than $1.0 billion in revenue during our most recently completed fiscal year, we qualify as an “emerging growth company” as defined in Section 2(a) of the Securities Act of 1933, as amended, which we refer to as the Securities Act, as modified by the Jumpstart Our Business Startups Act of 2012, or the JOBS Act. As an emerging growth company, we may take advantage of specified reduced disclosure and other requirements that are otherwise applicable, in general, to public companies that are not emerging growth companies. These provisions include:

• Reduced disclosure about our executive compensation arrangements;

• No non-binding shareholder advisory votes on executive compensation or golden parachute arrangements;

• Exemption from the auditor attestation requirement in the assessment of our internal control over financial reporting; and

• Reduced disclosure of certain financial information in this prospectus.

We will remain an emerging growth company until the earliest to occur of:

• the end of the fiscal year for which we report $1.0 billion or more in annual revenues;

• the end of the fiscal year in which the market value of our common stock held by non-affiliates exceeds $700 million on the last business day of our second fiscal quarter;

• our issuance, in a three year period, of more than $1.0 billion of non-convertible debt; and

• December 31, 2019.

The JOBS Act permits an emerging growth company to take advantage of an extended transition period to comply with new or revised accounting standards applicable to public companies. We are choosing to opt out of this provision and, as a result, we will comply with new or revised accounting standards as required when they are adopted. This decision to opt out of the extended transition period under the JOBS Act is irrevocable.

Company Information

Our predecessor company was incorporated in Delaware in May 2001. In June 2008, we completed a reorganization pursuant to which our predecessor company merged with and into a newly formed Delaware corporation, renamed Aspen Aerogels, Inc.

Our principal executive offices are located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532, and our telephone number is (508) 691-1111. Our website address is www.aerogel.com. The information contained on, or accessible from, our website is not incorporated by reference into this prospectus.

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The Offering

Common stock offered by us              shares (or              shares if the underwriters exercise their option to purchase additional shares in full)

Common stock to be outstanding immediately after this offering              shares (or              shares if the underwriters exercise their option to purchase additional shares in full)

Over-allotment option We have granted the underwriters a 30-day option to purchase up to              of additional shares of our common stock to cover over-allotments, if any.

Use of proceeds We estimate that the net proceeds to us from this offering, after deducting estimated underwriting discounts and estimated offering expenses payable by us, will be approximately $         million (or approximately $         million if the underwriters exercise their option to purchase additional shares in full) assuming an initial public offering price of $         per share, which is the mid-point of the estimated price range set forth on the cover page of this prospectus.

We intend to use:

• approximately $30 million of the net proceeds to fund the additional expenditures necessary for the design, development and construction of our third production line in our East Providence facility;

• approximately $         million of the net proceeds to repay amounts outstanding under our revolving line of credit, which is payable in July 2014, and approximately $19 million of the net proceeds to repay our 20% subordinated notes due September 2014; and

• the remaining net proceeds for general corporate purposes, which will include funding a portion of the design, development and construction of our planned second production plant in Europe or Asia after completion of our third production line.

See “Use of Proceeds” for more information.

Risk factors You should carefully read the “Risk Factors” section of this prospectus for a discussion of factors that you should consider before deciding to invest in shares of our common stock.

Proposed NYSE symbol “ASPN”

The number of shares of our common stock to be outstanding after this offering is based on                      shares of our common stock outstanding as of                     , 2014, after giving effect to the exercise of all of our outstanding warrants to purchase Series C preferred stock and the conversion of all of our preferred stock and convertible notes based on the assumptions set forth below immediately prior to the completion of this offering and excluding the following:

• 80,050,105 shares of our common stock issuable upon the exercise of stock options outstanding as of April 15, 2014 at a weighted-average exercise price of $0.112 per share, which share number assumes

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the closing of the offering made hereby occurs on                     , 2014 with an initial public offering price per share of $        , the mid-point of the price range set forth on the cover page of this prospectus;

•              shares of our common stock that will be available for future issuance under our 2014 equity incentive plan to be effective upon completion of this offering; and

• 112,576 shares of common stock issuable upon the exercise of warrants to purchase our common stock outstanding as of April 15, 2014 at a weighted-average exercise price of $0.017 per share.

Except as otherwise noted, all information in this prospectus:

• assumes the adoption of our restated certificate of incorporation and restated by-laws in connection with the consummation of the offering made hereby;

• assumes that the closing of the offering made hereby occurs on                     , 2014 with an initial public offering price per share of $        , the mid-point of the price range set forth on the cover page of this prospectus;

• assumes the issuance of              shares of our common stock upon closing of this offering comprised of:

• 96,333,792 shares of our common stock issuable upon the assumed cash exercise of our outstanding warrants to purchase Series C preferred stock and the automatic conversion of all outstanding shares of our preferred stock (which would be reduced by              shares in the event that the exercise price of all of our outstanding warrants to purchase Series C preferred stock was paid pursuant to the net exercise provisions of the warrants, based on an initial offering price of $        , the mid-point of the price range set forth on the cover page of this prospectus); and

•              shares of our common stock issuable upon the automatic conversion of our convertible notes including accrued but unpaid interest thereon at a conversion price equal to 62.5% of the initial public offering price per share in this offering;

• assumes the exchange by Arcapita Ventures I Limited, or Arcapita, immediately prior to this offering of its notes for a number of shares of our common stock based on the initial public offering price and a discount factor that will result in Arcapita receiving approximately the number of shares that it would have received if its notes, which it holds in lieu of convertible notes due to its investment restrictions, accrued interest and automatically converted upon the same terms as the convertible notes;

• reflects the 1-for-10 reverse split of our common stock and preferred stock which took place in August 2013;

• gives effect to a             -for-             reverse split of our common stock, which will take place prior to the closing of the offering made hereby; and

• assumes no exercise by the underwriters of their option to purchase additional shares.

We refer collectively to our Series A, B and C convertible preferred stock as our preferred stock. We refer to the automatic conversion of our preferred stock into shares of common stock and the automatic conversion of our convertible note (including accrued but unpaid interest) into shares of common stock as the preferred stock and convertible notes conversions. When we refer to our convertible notes, we are including the notes held by Arcapita and when we refer to the convertible notes conversions, we are including the exchange of Arcapita’s notes for shares of our common stock at a discount factor that will result in Arcapita receiving approximately the number of shares that it would have received if its notes, which it holds in lieu of convertible notes due to its investment restrictions, accrued interest and automatically converted upon the same terms as the convertible notes.

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Summary Consolidated Financial Data

The following tables present a summary of our consolidated financial data for the periods, and as of the dates, indicated. We derived the consolidated statement of operations data for the years ended December 31, 2011, 2012 and 2013 and the consolidated balance sheet data as of December 31, 2013 from our audited consolidated financial statements and the related notes thereto included elsewhere in this prospectus. Our historical results for prior periods are not necessarily indicative of results to be expected for any future period.

You should read this summary consolidated financial data together with our audited consolidated financial statements and the related notes thereto included elsewhere in this prospectus and the information under “Selected Consolidated Financial Data,” “Capitalization” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.”

	Year Ended December 31
	2011			2012			2013
	($ in thousands, except share and per share data)
Consolidated statements of operations data:
Revenue:
Product	$	42,717		$	60,389		$	82,057
Research services		3,233			3,064			4,037
Total revenue		45,950			63,453			86,094
Cost of revenue:
Product		47,071			70,025			73,399
Research services		1,505			1,396			1,964
Gross profit (loss)		(2,626	)		(7,968	)		10,731
Operating expenses:
Research and development		4,085			5,142			5,159
Sales and marketing		5,565			8,564			9,271
General and administrative		8,291			11,299			12,833
Write-off of construction in progress		—			—			3,440
Total operating expenses		17,941			25,005			30,703
Income (loss) from operations		(20,567	)		(32,973	)		(19,972	)
Other income (expense):
Interest expense(1)		(8,822	)		(21,790	)		(30,599	)
Gain on extinguishment of convertible notes		—			—			8,898
Loss on exchange of convertible notes		—			—			(5,697	)
Debt extinguishment costs		—			(1,379	)		—
Costs associated with postponed public offering		(3,443	)		—			(241	)
Total other income (expense), net		(12,265	)		(23,169	)		(27,639	)
Net income (loss)		(32,832	)		(56,142	)		(47,611	)
Accretion (deemed dividends) on preferred stock		(23,665	)		47,201			(996	)
Extinguishment of redeemable feature for convertible preferred stock		—			—			86,161
Earnings attributable to preferred stock shareholders		—			—			(36,216	)
Net income (loss) attributable to common stockholders	$	(56,497	)	$	(8,941	)	$	1,338

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	Year Ended December 31
	2011			2012			2013
	($ in thousands, except share and per share data)
Per share data:
Net income (loss) attributable to common stockholders per share:
Basic	$	(21.66	)	$	(3.41	)	$	0.51
Diluted	$	(21.66	)	$	(3.41	)	$	0.49
Weighted-average common shares outstanding:
Basic		2,607,888			2,622,897			2,623,156
Diluted		2,607,888			2,622,897			2,722,947
Pro forma net income (loss) per share:(2)
Basic
Diluted
Weighted-average common shares outstanding used in computing pro forma net income (loss) per share:(2)
Basic
Diluted

	Year Ended December 31
	2011			2012			2013
	(In thousands)
Other operating data:
Product shipments in square feet(3)		19,473			27,280			35,560
Adjusted EBITDA(4)	$	(11,982	)	$	(19,146	)	$	(1,815	)

	As of December 31, 2013
	Actual			As adjusted(5)
	($ in thousands)
Consolidated balance sheet data:
Cash	$	1,574
Working capital(6)		(3,460	)
Total assets		90,442
Total debt		138,555
Preferred stock		—
Total stockholders’ (deficit) equity		(61,966	)

(1) Interest expense consists primarily of fair market value adjustments related to our subordinated notes, convertible notes and the issuance of our Series C warrants, subordinated note and convertible note issuance costs, the amortization of the subordinated note debt discount and imputed interest on our obligations under our cross license agreements with Cabot Corporation.

(2) Pro forma per share data will be computed based upon the number of shares of common stock outstanding immediately after consummation of this offering applied to our historical net income (loss) amounts and will give retroactive effect to the preferred stock and convertible notes conversions (assuming an initial public offering price of $        , the mid-point of the price range set forth on the cover page of this prospectus) and the issuance of the shares of our common stock offered hereby.

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The following table presents the calculation of pro forma basic and diluted net income (loss) per share:

	Year Ended December 31
	2011			2012			2013
	($ in thousands, except share and per share data)
Net income (loss) attributable to common stockholders	$	(56,497	)	$	(8,941	)	$	1,338
Deemed dividends (accretion) on preferred stock		23,665			(47,201	)		996
Extinguishment of redeemable feature for convertible preferred stock		—			—			(86,161	)
Earnings attributable to preferred stock shareholders		—			—			36,216
Interest expense
Pro forma net income (loss) attributable to common stockholders
Weighted-average common shares outstanding, basic and diluted
Pro forma common shares issued upon conversion of preferred stock and exercise of Series C warrants
Pro forma common shares issued upon conversion of convertible notes and interest thereon
Weighted-average common shares outstanding used in computing pro forma net income (loss) per share, basic and diluted
Pro forma net income (loss) per share, basic and diluted

(3) We price our products and measure our product shipments associated with recognized revenue in square feet. We believe the square foot operating metric allows us and our investors to measure our sales volume on a uniform and consistent basis.

(4) We use Adjusted EBITDA, a non-GAAP financial measure, as a means to assess our operating performance. We define Adjusted EBITDA as net income (loss) before interest expense, taxes, depreciation, amortization, stock-based compensation expense and other items, from time to time, that we do not believe are indicative of our core operating performance, which recently have included loss on disposal of assets, gain or loss on extinguishment or exchange of debt, write-off of costs of postponed financing activities and write-off of construction in progress. Adjusted EBITDA is a supplemental measure of our performance that is not presented in accordance with GAAP. Adjusted EBITDA should not be considered as an alternative to net income (loss) or any other measure of financial performance calculated and presented in accordance with GAAP. In addition, our definition and presentation of Adjusted EBITDA may not be comparable to similarly titled measures presented by other companies.

We use Adjusted EBITDA as a measure of operating performance, because it does not include the impact of items that we do not consider indicative of our core operating performance, for planning purposes, including the preparation of our annual operating budget, to allocate resources to enhance the financial performance of our business and as a performance measure under our bonus plan. We also believe that the presentation of Adjusted EBITDA provides useful information to investors with respect to our results of operations and in assessing the performance and value of our business. Various measures of EBITDA are widely used by investors to measure a company’s operating performance without regard to items that can vary substantially from company to company depending upon financing and accounting methods, book values of assets, capital structures and the methods by which assets were acquired.

Although measures similar to Adjusted EBITDA are frequently used by investors and securities analysts in their evaluation of companies, we understand that Adjusted EBITDA has limitations as an analytical

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tool, and you should not consider it in isolation or as a substitute for GAAP, income from operations or an analysis of our results of operations as reported under GAAP. Some of these limitations are:

• Adjusted EBITDA does not reflect our historical cash expenditures or future requirements for capital expenditures or other contractual commitments;

• Adjusted EBITDA does not reflect changes in, or cash requirements for, our working capital needs;

• Adjusted EBITDA does not reflect stock-based compensation expense;

• Adjusted EBITDA does not reflect our tax expense or cash requirements to pay our income taxes;

• Adjusted EBITDA does not reflect our interest expense, or the cash requirements necessary to service interest or principal payments on our debt;

• Although depreciation, amortization and impairment charges are non-cash charges, the assets being depreciated, amortized or impaired will often have to be replaced in the future, and Adjusted EBITDA does not reflect any cash requirements for these replacements; and

• Other companies in our industry may calculate EBITDA or Adjusted EBITDA differently than we do, limiting their usefulness as a comparative measure.

Because of these limitations, our Adjusted EBITDA should not be considered as a measure of discretionary cash available to us to reinvest in the growth of our business or as a measure of cash available for us to meet our obligations.

To properly and prudently evaluate our business, we encourage you to review the GAAP financial statements included elsewhere in this prospectus and not to rely on any single financial measure to evaluate our business.

The following table presents a reconciliation of net income (loss), the most directly comparable GAAP measure, to Adjusted EBITDA for the periods presented:

	Year Ended December 31
	2011			2012			2013
	($ in thousands)
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)
Interest expense		8,822			21,790			30,599
Depreciation and amortization		7,521			9,684			10,061
Loss on disposal of assets		—			2,489			230
Stock-based compensation		1,064			1,654			4,426
Gain on extinguishment of convertible notes		—			—			(8,898	)
Loss on exchange of convertible notes		—			—			5,697
Debt extinguishment costs		—			1,379			—
Write-off of costs associated with postponed public offering		3,443			—			241
Write-off of construction in progress		—			—			3,440
Adjusted EBITDA	$	(11,982	)	$	(19,146	)	$	(1,815	)

(5) The summary as adjusted balance sheet information as of December 31, 2013 has been prepared to give effect to this offering, our use of a portion of the net proceeds therefrom to repay all outstanding amounts under our revolving credit facility if any, and under our subordinated notes therefrom and the preferred stock and convertible notes conversions as if they had occurred on December 31, 2013. The summary as adjusted balance sheet information is for informational purposes only and does not purport to indicate balance sheet information as of any future date.

(6) Working capital means current assets minus current liabilities. It includes $18.8 million of current maturities of debt and other liabilities that are also included in total debt.

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RISK FACTORS

Investing in our common stock involves a high degree of risk. You should carefully consider the risks described below and all of the other information set forth in this prospectus, including our consolidated financial statements and the related notes thereto, before deciding to invest in our common stock. If any of the events or developments described below occurs, our business, financial condition or results of operations could be negatively affected. In that case, the market price of our common stock could decline, and you could lose all or part of your investment.

Risks Related to Our Business and Strategy

We have incurred net losses since our inception, and we may continue to incur net losses in the future and may never reach profitability.

We have a history of losses, and we may not ever achieve profitability. We experienced net losses of $32.8 million, $56.1 million and $47.6 million for the years ended December 31, 2011, 2012 and 2013, respectively. As of December 31, 2013, our accumulated deficit was $332.8 million and total stockholders’ deficit was $62.0 million. We expect to continue to incur operating losses as a result of expenses associated with the continued development and expansion of our business. Our expenses include sales and marketing, research and development, and general and administrative costs. Furthermore, these expenses are not the only factors that may contribute to our net losses. For example, interest expense on our currently outstanding debt and on any debt that we incur in the future could contribute to our net losses. Any failure to increase revenue or manage our cost structure as we implement initiatives to grow our business could prevent us from achieving profitability, or sustaining profitability if we do achieve it. In addition, our ability to achieve profitability is subject to a number of the risks and uncertainties discussed below, many of which are beyond our control. Failure to become and remain profitable may adversely affect the market price of our common stock and our ability to raise capital and continue operations.

We have yet to achieve positive cash flow, and our ability to generate positive cash flow is uncertain.

To develop and expand our business, we have made significant up-front investments in our manufacturing capacity and incurred research and development, sales and marketing and general and administrative expenses. In addition, our growth has required a significant investment in working capital over the last several years. We have had negative cash flows from operating activities of $24.2 million, $25.9 million and $13.7 million for the years ended December 31, 2011, 2012 and 2013, respectively.

We expect that for the foreseeable future our overall cash flow will remain negative. In particular, we will need cash to fund our significant planned future capital expenditures to expand our manufacturing capacity. We will also require significant amounts of working capital to support our growth and we will need to increase our inventories of raw materials and our products as we seek to grow our business. In addition, from time to time, we may have debt maturities that will require cash in order to repay those obligations. We may not achieve sufficient revenue growth to generate positive future cash flow and, therefore, we may need to raise additional capital from investors to achieve our expected growth. An inability to generate positive cash flow for the foreseeable future or raise additional capital on reasonable terms, if at all, may decrease our long-term viability.

Our independent registered public accounting firm’s report contains an explanatory paragraph that expresses substantial doubt about our ability to continue as a going concern.

As a result of our recurring net losses taken together with the maturity of our subordinated notes due September 2014 and the expiration of our revolving credit facility in July 2014, our independent registered public accounting firm has expressed substantial doubt regarding our ability to continue as a going concern. We plan to repay our subordinated notes and borrowings under our revolving credit facility with a portion of the net proceeds of this offering.

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We are dependent on a sole manufacturing facility. Any significant disruption to this facility or the failure of either of our two production lines in this facility to operate according to our expectation could have a material adverse effect on our business and results of operations.

We currently operate only two production lines in one manufacturing facility, which is located in East Providence, Rhode Island. Our ability to meet the demands of our customers depends on efficient, proper and uninterrupted operations at this manufacturing facility. In the event of a significant disruption to our sole manufacturing facility or breakdown of either production line, we currently do not expect that we would have sufficient inventory in stock to meet demand until the production lines return to operation.

Power failures or disruptions, the breakdown, failure or substandard performance of equipment, or the damage or destruction of buildings and other facilities due to fire or natural disasters could severely affect our ability to continue our operations. In the event of such disruptions, we are unlikely to find suitable alternatives or may not be able to make needed repairs on a timely basis and at reasonable cost, which could have a material adverse effect on our business and results of operations. In particular, our manufacturing processes include the use of both high temperatures and flammable chemicals, which subjects us to a significant risk of loss resulting from fire. We had occasional incidences of fires at our initial facility in Northborough, Massachusetts that preceded our current manufacturing facility in East Providence, Rhode Island. If our manufacturing facility were to be damaged or cease operations, it may reduce revenue, cause us to lose customers and otherwise adversely affect our business. The insurance policies we maintain to cover losses caused by fire or natural disaster, including business interruption insurance, may not adequately compensate us for any such losses and will not address a loss of customers that we would expect would result. If our sole manufacturing facility was damaged or destroyed prior to the commencement of operations at a second manufacturing facility, which is currently expected to be 2017, we would be unable to operate our business for an extended period of time and our business and results of operations may be materially adversely affected, potentially even threatening our viability.

If we fail to achieve the increase in production capacity that our continued growth requires in a timely manner, or at all, our growth may be hindered and our business or results of operations may be materially adversely affected.

Our continued growth requires that we increase our production capacity. Consequently, we are engaged in the design, engineering and initial procurement phase of building a third production line in our manufacturing facility in East Providence and also plan to construct a second manufacturing facility located in either Europe or Asia. If, for any reason, including our inability to obtain financing, the third production line or the second manufacturing facility should fail to be completed in a timely manner, or at all, or any of the production lines in any future manufacturing facilities do not operate according to our expectations, sales may be impeded, our growth may be hindered and our business or results of operations may be materially adversely affected.

Many factors could delay or prevent the addition of a third production line or the construction of a second manufacturing facility or cause us to reduce the scale or scope of the new facilities, including:

• our inability to obtain financing on favorable terms, or at all;

• design, engineering and construction difficulties or delays;

• our failure or delay in obtaining necessary legal, regulatory and other approvals;

• interruptions in the supply of the necessary equipment, or construction materials or labor or an increase in their price;

• opposition of local interests; and

• natural disasters, accidents, political unrest or unforeseen events.

Many factors could prevent the third production line or the second manufacturing facility from producing at their expected effective or nameplate capacity or could cause us to reduce the scale or scope of the new facilities, including:

• design and engineering failures;

• inability to retain and train a skilled workforce;

• the challenges of operating significantly higher volume equipment at the planned second facility than currently employed at our existing facility in East Providence;

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• improper operation of the manufacturing equipment;

• decreases in our manufacturing yields due to an increase in the cost of the materials needed to make our products or the inefficient use of these materials in our manufacturing process;

• strikes or labor disputes; and

• damage to the manufacturing equipment due to design and engineering flaws, construction difficulties or operator error.

Any such expansion will place a significant strain on our senior management team and our financial and other resources. The costs associated with our expansion could exceed our expectations and result in a materially adverse impact on our business, results of operations, financial condition and cash flows.

If we are unable to complete the projects contemplated, the costs incurred in connection with such projects may not be recoverable. For example, during 2013, we redesigned and reduced the planned scale of the third production line. As a result, we reviewed the construction in progress assets associated with the third production line and determined that $3.0 million had no future use. In addition, we concluded that an additional $0.4 million of construction in progress assets were not utilized or functional. Accordingly, we recorded a $3.4 million impairment charge during 2013 related to the write-off of construction in progress assets. A similar redesign or reduction in scale could affect the planned third production line or the second manufacturing facility and similar impairments of our assets in the future could harm our financial condition.

If the expected growth in the demand for our products does not follow each of our planned capacity expansions, then our business will be materially adversely affected.

As we pursue our capacity expansion plans, we will incur significant capital expenses and increased levels of manufacturing expenses in anticipation of expected growth in demand for our products. In particular, we expect that these substantial additional expenditures will be made by us significantly in advance of the existence of the level of demand that would ensure the most efficient use of our planned new capacity. As a result, if the expected growth in demand for our products fails to materialize within a reasonable amount of time following each of our planned capacity expansions, then we would suffer decreased levels of cash flow and our financial condition and results of operations would be adversely affected.

We will require significant additional capital to pursue our growth strategy beyond the construction of our third line in our East Providence facility, but we may not be able to obtain additional financing on acceptable terms or at all.

The growth of our business will depend on substantial amounts of additional capital for construction of new production lines or facilities, ongoing operating expenses and continued development of our aerogel product lines. Our capital requirements will depend on many factors, including the rate of our revenue growth, our introduction of new products and enhancements to existing products, and our expansion of sales and marketing and product development activities. In particular, our plans to construct a second manufacturing facility in Europe or Asia are dependent on our ability to secure grants from governments and to raise debt financing. There is no assurance of our ability to obtain either type of financing on terms acceptable to us or at all.

In addition, we may consider strategic acquisitions of complementary businesses or technologies to grow our business, which could require significant capital and could increase our capital expenditures related to future operation of the acquired business or technology.

We may not be able to obtain loans or additional capital on acceptable terms or at all. Moreover, our loan and security agreement with Silicon Valley Bank under which we have the ability to borrow up to $10.0 million and our subordinated notes contain restrictions on our ability to incur additional indebtedness, which, if not waived, could prevent us from obtaining needed capital. Any future credit facilities or debt instruments would likely contain similar restrictions. We may not be able to obtain bank credit arrangements or effect an equity or debt financing on terms acceptable to us or at all in order to fund our future capacity expansion plans. A failure to obtain additional financing when needed could adversely affect our ability to maintain and grow our business.

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The market for insulation products incorporating aerogel blankets is relatively undeveloped and our products may never be widely adopted, which would have a material adverse effect on our business.

The market for insulation products utilizing aerogel blankets is relatively undeveloped. Accordingly, our future results of operation will depend in large part on our ability to gain market share of the global energy infrastructure insulation market. Our ability to gain market share in this market is highly dependent on the acceptance of our products by large, well-established end-users, distributors, contractors and OEMs. The energy infrastructure insulation market has historically been slow to adopt new technologies and products. Most insulation types currently in use in these markets have been in use for over 50 years. In addition, there is a tendency of end-users in some of our markets to opt for the frequently lower short-term costs of traditional insulation materials. If we fail to successfully educate existing and potential end-users, distributors, contractors and OEMs regarding the benefits of our aerogel products, or if existing users of our products no longer rely on aerogel insulation for their insulation needs, our ability to sell our products and grow our business could be limited.

In particular, because we are still often a new supplier to our end-use customers, we may face concerns from these end-use customers about our reliability and our ability to produce our products in a volume sufficient to meet their supply needs. As a result, we may experience a reluctance or unwillingness by existing end-use customers to expand their use of our products and by potential end-use customers to begin using our products. Our products may never reach mass adoption, and changes or advances in technologies could adversely affect the demand for our products. A failure to increase, or a decrease in, demand for aerogel insulation products caused by lack of end-user or distribution channel acceptance, technological challenges or competing technologies and products would result in a lower revenue growth rate or decreased revenue, either of which could materially adversely affect our business and results of operations.

Our products are expensive relative to other insulation products, which could make it more difficult for us to grow our revenue and achieve broader adoption of our aerogel products.

While we believe our products have superior performance attributes and may sometimes have the lowest cost on a fully-installed basis or offer life-cycle cost savings, our competitors offer many traditional insulation products that are priced below our products. Our products are expensive relative to other insulation products and end-use customers may not value our products’ performance attributes sufficiently to pay their premium price. This could make it more difficult for us to grow our revenue and achieve broader adoption of our aerogel products. In addition, some of the benefits of our products are based on reduced installation time and related labor expense. In regions where labor costs are significantly lower than in the United States and Europe, the cost benefits of reduced installation times may not be adequate to overcome the relatively high price of our products and may make it more difficult for us to grow our revenue in such regions.

Growth has placed significant demands on our management systems and our infrastructure. If we fail to manage our growth effectively, we may be unable to execute our business plan, address competitive challenges and meet our customers’ product specifications and delivery requirements.

We may be unable to manage our growth. To manage our anticipated future growth, we must continue to:

• improve our existing, and implement additional, managerial capabilities, manufacturing, sales and marketing, and engineering operations, research and development capabilities, regulatory compliance systems and financial control and reporting systems;

• expand our manufacturing and distribution facilities; and

• continue to recruit and train additional qualified personnel.

All of these measures will require significant expenditures and will demand the attention of management. At certain points in the past, significant growth in demand for our product has put our management and manufacturing systems under strain. As a result, there have been periods of time when we have had difficulty

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consistently producing product that met our specifications. In addition, the physical expansion of our operations may lead to significant costs and may divert our management and business development resources. Furthermore, we compete for personnel and advisors with other companies and other organizations, many of which are larger and have greater name recognition and financial and other resources than we do. Due to our limited resources, we may not be able to effectively manage the expansion of our operations or recruit and adequately train additional qualified personnel or retain personnel. Any inability to manage growth could result in a loss of existing customers and revenues and delay the execution of our business plans, disrupt our operations or result in financial, contractual or other liabilities. If we fail to achieve the necessary level of efficiency in our organization as it grows, our business, results of operations and financial condition would be harmed.

We allocate our operations, sales and marketing, research and development, general and administrative and financial resources based on our business plan, which includes assumptions about current and future orders from customers. However, these factors are uncertain. If our assumptions regarding these factors prove to be incorrect or if competing products gain further acceptance, then actual demand for our aerogel products could be significantly less than the demand we anticipate and we may not be able to sustain our revenue growth or achieve profitability.

The markets we serve are subject to general economic conditions and cyclical demand, which could harm our business and lead to significant shifts in our results of operations from quarter to quarter that make it difficult to project long-term performance.

Our results of operations have been, and may in the future be, adversely affected by general economic conditions and the cyclical pattern of certain industries in which our customers and end-users operate. Demand for our products and services depends in large part upon the level of capital and maintenance expenditures by many of our customers and end-users, in particular those in the energy, petrochemical and power generation industries, and firms that design, construct and operate facilities for these industries. These customers’ expenditures historically have been cyclical in nature and vulnerable to economic downturns. In particular, profitability in the energy industry is highly sensitive to supply and demand cycles and commodity prices, which historically have been volatile; and our customers in this industry historically have tended to delay large capital projects, including expensive maintenance and upgrades, during industry downturns. Customer project delays may cause fluctuations in the timing or the amount of revenue earned and our results of operations in a particular period. Prolonged periods of little or no economic growth could decrease demand for oil and gas which, in turn, could result in lower demand for our products and a negative impact on our results of operations and cash flows. In addition, this historically cyclical demand and potential customer project delays may lead to significant shifts in our results of operations from quarter to quarter, which limits our ability to make accurate long-term predictions about our future performance. We estimate that sales to end-use customers in the energy industry accounted for approximately 87% of our 2013 revenues and we expect that they will account for a significant portion of our future revenues.

A sustained downturn in the energy industry, due to reduced energy demand or lower oil and gas prices, could decrease demand for some of our products and services, which could have a material adverse effect on our business, financial condition and results of operations.

Demand for a significant portion of our products and services depends upon the level of capital expenditure by companies in the energy industry, which depends, in part, on energy prices. Prices of oil and gas have been very volatile over the past three years, with significant increases until achieving historic highs in July 2008, followed immediately by a steep decline through 2009, a moderate increase throughout 2010 and continued volatility from 2011 through 2013. A sustained downturn in the capital expenditures of our customers, whether due to a decrease in the market price of oil and gas or otherwise, may delay projects, decrease demand for our products and services and cause downward pressure on the prices we charge, which, in turn, could have a material adverse effect on our business, financial condition and results of operations. Such downturns, including the perception that they might continue, could have a significant negative impact on the market price of our common stock.

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A substantial portion of our revenue comes from sales in foreign countries and we may expand our operations outside of the United States, which subjects us to increased economic, operational and political risks that could increase our costs and make it difficult for us to continue to operate profitably.

A substantial portion of our sales are to shipment destinations outside the United States, including in Canada, Taiwan, Brazil, South Korea, Norway, Japan, Germany, Singapore, India and the United Kingdom. Total revenue generated from outside of the United States, based on our shipment destination or research services location, amounted to $30.8 million or 67% of revenue, $43.5 million or 69% of revenue, and $55.9 million or 65% of revenue, in the years ended December 31, 2011, 2012 and 2013, respectively. In addition, we may expand our operations outside of the United States, including our manufacturing operations in connection with our planned second manufacturing facility expected to be located in Europe or Asia. As a result, we are subject to a number of risks, including, but not limited to:

• labor rules and collective bargaining arrangements in foreign jurisdictions, particularly with respect to our planned second manufacturing facility in Europe or Asia;

• difficulty in staffing and managing (including ensuring compliance with internal policies and controls) geographically widespread operations;

• the effect of applicable U.S. and foreign tax structures, including tax rates that may be higher than tax rates in the United States or taxes that may be duplicative of those imposed in the United States;

• trade relations between the United States and those foreign countries in which our customers and suppliers have operations, including protectionist measures such as tariffs and import or export licensing requirements;

• general economic and political conditions in each country, which may interfere with, among other things, our supply chain, our customers and all of our activities in a particular location;

• difficulty in the enforcement of contractual obligations in non-U.S. jurisdictions and the collection of accounts receivable from foreign accounts;

• different regulatory regimes in the various countries in which we operate or sell our products;

• inadequate intellectual property protection in foreign countries;

• the difficulties and increased expense in complying with multiple and potentially conflicting domestic and foreign laws, regulations, product approvals and trade standards, including the U.S. Foreign Corrupt Practices Act and similar anti-bribery laws in non-U.S. jurisdictions, as well as the rules and regulations of the U.S. Office of Foreign Assets Control and similar sanctions laws;

• foreign currency exchange controls, restrictions and fluctuations, which could result in reduced revenue and increased operating expense;

• transportation delays or interruptions; and

• terrorist activity and political unrest, particularly given the use of our products at energy facilities.

Our success will depend in large part on our ability to manage the effects of continued global political or economic uncertainty, especially in our significant geographic markets.

Because of our significant international operations we could be materially adversely affected by violations of the U.S. Foreign Corrupt Practices Act and similar anti-corruption, anti-bribery and anti-kickback laws.

We operate on a global basis, with 68% of our product sales in 2013 being made to destinations outside the United States, including Canada, Europe, Asia, South America and the Middle East. Our business operations and sales in countries outside the United States are subject to anti-corruption, anti-bribery and anti-kickback laws and regulations, including restrictions imposed by the Foreign Corrupt Practices Act, or FCPA, as well as the United Kingdom Bribery Act of 2010, or UK Bribery Act. The FCPA, UK Bribery Act, and similar anti-corruption, anti-bribery and anti-kickback laws in other jurisdictions generally prohibit companies and their intermediaries and agents from making improper payments to government officials or any other persons for the purpose of obtaining or retaining business. We operate and sell our products in many parts of the world that have

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experienced governmental corruption to some degree and, in certain circumstances, strict compliance with anti-corruption, anti-bribery and anti-kickback laws may conflict with local customs and practices. We train our employees concerning anti-corruption, anti-bribery and anti-kickback laws and have policies in place that prohibit employees from making improper payments. We are implementing internal controls and procedures designed to ensure that we comply with anti-corruption, anti-bribery and anti-kickback laws, rules and regulations and mitigate and protect against corruption risks. We cannot provide assurance that our internal controls and procedures will protect us from reckless, criminal or other acts committed by our employees or third-parties with whom we work. If we are found to be liable for violations of the FCPA or similar anti-corruption, anti-bribery and anti-kickback laws in international jurisdictions, either due to our own acts or out of inadvertence, or due to the acts or inadvertence of others, we could suffer criminal or civil fines or penalties or other repercussions, including reputational harm, which could have a material and adverse effect on our business, results of operations and financial condition.

A failure to comply with export control or economic sanctions laws and regulations could have a material adverse impact on our business, results of operations or financial condition. We may be unable to ensure that our distributors comply with applicable sanctions and export control laws.

We operate on a global basis, with 68% of our product sales in 2013 being made to destinations outside the United States, including Canada, Europe, Asia, South America and the Middle East. We face several risks inherent in conducting business internationally, including compliance with applicable economic sanctions laws and regulations, such as laws and regulations administered by the United States Department of Treasury’s Office of Foreign Assets Control, or OFAC, the United States Department of State and the United States Department of Commerce. We must also comply with all applicable export control laws and regulations of the United States and other countries. Violations of these laws or regulations could result in significant additional sanctions including criminal or civil fines or penalties, more onerous compliance requirements, more extensive debarments from export privileges or loss of authorizations needed to conduct aspects of our international business.

In certain countries, we may engage third party agents or intermediaries, such as customs agents, to act on our behalf and if these third party agents or intermediaries violate applicable laws, their actions may result in criminal or civil fines or penalties or other sanctions being assessed against us. We take certain measures designed to ensure our compliance with U.S. export and economic sanctions law and we believe that we have never sold our products to Iran, Cuba, Sudan or Syria through third party agents or intermediaries or made any effort to attract business from any of these countries. However, it is possible that some of our products were sold or will be sold to distributors or other parties that, without our knowledge or consent, re-exported or will re-export such products to these countries. Although none of our non-U.S. distributors are located in, or to our knowledge, conduct business with Iran, Cuba, Sudan or Syria, we may not be successful in ensuring compliance with limitations or restrictions on business with these or other countries subject to economic sanctions. There can be no assurance that we will be in compliance with export control or economic sanctions laws and regulations in the future. Any such violation could result in significant criminal or civil fines, penalties or other sanctions and repercussions, including reputational harm, that could materially adversely impact our business, results of operations or financial condition.

We rely on sales to a limited number of direct customers, including distributors, contractors and OEMs, for the substantial majority of our revenue, and the loss of one or more significant direct customers or several or our smaller direct customers could materially harm our business. In addition, we understand from our direct customers that a substantial majority of their sales of our products are to a small number of end-use customers and the loss of one or more significant end-use customers or several of our smaller end-use customers could materially harm our business.

A substantial majority of our revenue is generated from sales to a limited number of direct customers, including distributors, contractors and OEMs. For the years ended December 31, 2011, 2012 and 2013, total revenue from our top ten direct customers represented 60%, 59% and 65% of our revenues, respectively. In 2011, Enershield Industries Ltd. represented 13% of our total revenue and Aerogel Korea Co., Ltd. represented 10% of our total revenue; in 2012, Distribution International represented 13% of our total revenue; and in 2013, Distribution International, Inc. represented 15% of our total revenue and AllTech Consulting Co., Ltd.

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represented 11% of our total revenue. For each of the periods discussed above, there were no other customers that represented 10% or more of our total revenues. Although the composition of our significant distributors, contractors and OEMs will vary from period to period, we expect that most of our revenues will continue, for the foreseeable future, to come from sales to a relatively small number of direct customers. In addition, we understand from our direct customers that a substantial majority of their sales of our products are to a small number of end-use customers.

Our direct customer concentration also creates risk for accounts receivable exposure. As of December 31, 2013, three of our direct customers accounted for 20%, 14% and 11% of our accounts receivable, respectively.

The majority of our sales to distributors are effected on a purchase order basis. The contracts we enter into with our direct customers generally do not include long-term commitments or minimum volumes that ensure future sales of our products. In addition, we understand that our direct customers’ contracts with end-use customers also generally do not include such commitments or minimums. Consequently, our results of operations may fluctuate significantly from period-to-period based on the actions of one or more significant direct customers or end-use customers.

A direct customer may take actions that affect us for reasons that we cannot anticipate or control, such as reasons related to an end-use customer’s financial condition, changes in business strategy or operations, the introduction of alternative competing products or as the result of the perceived quality or cost-effectiveness of our products. Our agreements with these direct customers may be cancelled if we fail to meet certain product specifications or materially breach the agreement or for other reasons outside of our control. In addition, our direct customers may seek to renegotiate the terms of current agreements or renewals. The loss of, or a reduction in sales or anticipated sales to, one or more of our significant direct customers or end-use customers or several of our smaller direct customers or end-use customers could have a material adverse effect on our business, financial condition and results of operations.

If we are unable to maintain our technological advantage over our competitors, our business may be adversely affected.

We are researching, developing, manufacturing and selling high-performance aerogel insulation products. Rapid and ongoing changes in technology and product standards could quickly render our products less competitive, or even obsolete, particularly if we fail to continue to improve the performance of our insulation products. We are currently developing new applications for our existing products as well as new aerogel technologies; however, we may not be successful in doing so and new applications or technologies may not be commercially useful. Other companies that are seeking to enhance traditional insulation materials have recently introduced or are developing other emerging and potential insulation technologies. These competitors are engaged in significant development work on these various insulation products. Competing technologies that outperform our insulation in one or more performance attributes could be developed and successfully introduced. We are also aware of certain companies that have developed or are developing products using aerogel technology similar to our technology and these or other companies could introduce aerogel products that compete directly with our products and outperform them in one or more performance attributes. As a result of this competition and potential competition, our products may not compete effectively in our target markets.

The energy infrastructure insulation market is highly competitive; if we are unable to compete successfully, we may not be able to increase or maintain our market share and revenues.

We face strong competition primarily from established manufacturers of traditional insulation materials. Large producers of traditional insulation materials, such as Johns Mansville, Saint-Gobain, Knauf Gips, Owens Corning and Rockwool, dominate the insulation market. In addition, we face competition from other companies seeking to develop high-performance insulation materials, including aerogel insulation. For example, Cabot Corporation manufactures, markets and sells a different form of aerogel insulation that is competitive with our products, particularly in the offshore oil and gas sector for use in pipe-in-pipe applications. Many of our competitors are substantially larger and better capitalized than we are and possess greater financial resources. In

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addition, we are aware of competitors in China that manufacture and market aerogel insulation products. Our competitors could focus their substantial financial resources to develop new or additional competing products or develop products that are more attractive to potential customers than the products that we offer.

Because some insulation manufacturers are substantially larger and better capitalized than we are, they may have the ability to sell their products at substantially lower costs to a large, existing customer base. Our products are expensive relative to other insulation products and end-use customers may not value our products’ superior performance attributes sufficiently to pay their premium price. In addition, from time to time we may increase the prices for our products and these price increases may not be accepted by our end-use customers and could result in a decreased demand for our products. Similarly, we may make changes to our products in order to respond to customer demand or to improve their performance attributes and these changes may not be accepted by our end-use customers and could result in a decrease in demand for our products. Any of these competitive factors could make it more difficult for us to attract and retain customers, cause us to lower our prices in order to compete and reduce our market share and revenues, any of which could have a material adverse effect on our financial condition and results of operations.

Negative perceptions regarding the safety or other attributes of our products or a failure or a perceived failure of our products could have a material adverse effect on our results of operations and could make us unable to continue our business.

Given the history of asbestos as an insulation material, we believe that there is an elevated level of attention towards perceived health and safety risks in the insulation industry. As a consequence, it is essential to our existing business and to our future growth that our products are considered safe. Even modest perceptions by existing or potential distributors, contractors or end-use customers in our target markets that our products are not safe could have a critical impact on our ability to sell our products and to continue as a business. There is risk of an actual or perceived failure of our products or other negative perceptions regarding our products, such as perceived health hazards. For example, dust is produced by our products during their installation and use, which increases the likelihood of the perception of hazard. Another example is the potential for material failure in very high temperature applications. Like most insulation products, our Pyrogel XT and XT-E products will normally go through a controlled burn-in process immediately after exposure to very high temperatures. If installed improperly, the burn-in may proceed too rapidly and the material may become damaged. Further, our competitors have in the past, and may in the future, seek to perpetuate such perceptions. We are currently taking steps to educate our distributors, contractors, OEMs and end-use customers on the nature of our products and the proper installation procedures in order to mitigate these risks. Such an event, or the perception of such an event, could quickly result in our direct and end-use customers replacing our products with traditional insulation materials which could have a material adverse effect on our results of operations.

Our activities and operations are subject to numerous health and safety laws and regulations. If we violate such regulations, we could face penalties and fines or be required to curtail or cease operations.

We are subject to numerous health and safety laws and regulations in each of the jurisdictions in which we operate. These health and safety laws and regulations apply to us including with regards to hazardous substances that we use in our manufacturing process and that certain of our products contain. These hazardous substances include titanium dioxide and carbon black, each of which has been determined, in certain forms and at certain levels, to be possibly carcinogenic or otherwise harmful to humans. Our processes also require the use of other regulated substances in raw material delivery and manufacturing, including among others, ethanol. These laws and regulations require us to obtain and maintain permits and approvals and implement health and safety programs and procedures to control risks associated with our operations. Compliance with those laws and regulations can require us to incur substantial costs. Moreover, if our compliance programs are not successful, we could be subject to penalties or to revocation of our permits, which may require us to curtail or cease operations of the affected facilities. In particular, the construction of our third production line in our East Providence facility will require us to obtain new permits from various regulatory authorities and if the issuance of such permits was delayed or denied, it would slow or potentially prevent the expansion of our manufacturing capacity. Violations of laws, regulations and permit requirements may also result in criminal sanctions or injunctions.

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While we use hazardous substances, including titanium dioxide and carbon black, in forms and at levels that are subject to current rules and regulations, such rules and regulations may become more stringent such that we are required to modify our manufacturing process and such that our customers’ use of our products may be impacted. In addition, changes in our production or manufacturing process may result in uses above currently permitted levels. Such uses or changes in rules or regulations could materially adversely affect our business, financial condition and results of operations.

Health and safety laws, regulations and permit requirements may become more stringent or otherwise change. Any such changes could require us to incur materially higher costs than we currently have. Our costs of complying with current and future health and safety laws, regulations and permit requirements, and any liabilities, fines or other sanctions resulting from violations of them, could adversely affect our business, financial condition and results of operations.

Our revenue may fluctuate, which may result in a high degree of variability in our results of operations and make it difficult for us to plan based on our future outlook and to forecast our future performance.

Our revenue may fluctuate from period to period due to a wide variety of factors. Since we rely on sales to a limited number of direct customers and end-use customers, changes in demand from one or more direct customers or end-users can significantly impact our revenue from period to period. In addition, the sales cycles for our products, including their qualification for use, are long and can result in unpredictability in our revenues. We expect to have an increasing percentage of our products sold for use in capital projects, which orders tend to be larger and more sporadic, that will further increase this unpredictability and the difficulty for us in forecasting quarterly or annual performance. Because of these factors, we have a limited basis on which to predict our quarterly revenue. Our profitability from period-to-period may also vary due to the mix of products that we sell in different periods. These factors may result in a high degree of variability in our results of operations and will make it difficult for us to accurately evaluate and plan based on our future outlook and to forecast quarterly or annual performance.

Our results of operations could be adversely affected if our operating expenses incurred do not correspond with the timing of our revenues.

Most of our operating expenses, such as manufacturing facility expenses, employee compensation and research expenses, are either relatively fixed in the short-term or incurred in advance of sales. In addition, our spending levels are based in part on our expectations regarding future revenues. As a result, if revenues for a particular quarter are below expectations, we may not be able to proportionately reduce operating expenses for that quarter. Our reliance on sales to a limited number of direct customers and end-use customers, the length of our sales cycles and the potentially increasing percentage of our products sold for use in capital projects each can cause sporadic demand for our products which would limit our ability to predict future sales. This limitation could result in our being unable to reduce spending quickly enough to compensate for reductions in sales and could therefore adversely affect our results of operations for any particular operating period.

Shortages of the raw materials used in the production of our products, increases in the cost of such materials or disruptions in our supply chain could adversely impact our financial condition and results of operations.

The raw materials used in the production of our products consist primarily of polyester and glass fiber battings, silica precursors and additives. Although we are not dependent on any one supplier, we are dependent on the ability of our third-party suppliers to supply such materials on a timely and consistent basis. While these raw materials are available from numerous sources, they may be subject to fluctuations in availability and price. In addition, fluctuations in ethanol prices may affect the cost of silica precursors. Our third-party suppliers may not dedicate sufficient resources to meet our scheduled delivery requirements or our suppliers may not have sufficient resources to satisfy our requirements during any period of sustained demand. Failure of suppliers to supply, delays in supplying or disruptions in the supply chain for our raw materials, or allocations in the supply of certain high demand raw components, could materially adversely affect our ability to meet our delivery schedules on a timely and competitive basis and results of operations.

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Fluctuations in the prices of these raw materials could have a material adverse effect on results of operations. Our ability to pass increases in raw material prices on to our customers is limited due to competitive pricing pressure and the time lag between increased costs and implementation of related price increases.

In particular, we purchase silica precursors from several suppliers, mostly pursuant to individual purchase orders and not pursuant to long-term contracts. We do not have a secure, long-term supply of silica precursors. We may not be able to establish arrangements for secure, long-term silica precursors supplies at prices consistent with our current costs or may incur a delay in supply while we seek alternative sources. Any inability to continue to purchase silica precursors pursuant to purchase orders, without long-term agreements in place, or to otherwise establish a long-term supply of silica precursors at prices consistent with our current costs, would have a material adverse effect on our ability to increase our sales and achieve profitability.

If we do not continue to develop and maintain distribution channels for our products and to meet our customers’ demand for our products, our results of operations could be adversely affected.

For a significant portion of our revenues, we rely on sales to distributors who then sell our products to end-users in our target markets. Our success depends, in part, on our maintaining satisfactory relationships with these distributors. Our distributors require us to meet expectations of delivery, quality and pricing of our products, at both the distribution channel level and at the level of the end-user of our products. If we fail to meet expected standards, our revenues would decline and this could materially adversely affect our business, results of operations and financial condition. In addition, we have been unable at times to produce sufficient amounts of our products to meet demand from our customers and we may not be able to avoid capacity constraints in the future if demand exceeds our expectations or we fail to bring into operation as planned the third production line at our East Providence facility or the second manufacturing facility to be located in Europe or Asia. If we are unable to deliver our products within such short timeframes, we may be at risk of losing direct or end-use customers. Accordingly, shortfalls in sales could materially adversely affect our business and results of operations.

The qualification process for our products can be lengthy and unpredictable, potentially delaying adoption of our products and incurring significant expense.

Qualification of our products by many of our direct and end-use customers can be lengthy and unpredictable and many of these direct and end-use customers have extended budgeting and procurement processes. This extended sales process requires the dedication of significant time by our personnel and our use of significant financial resources, with no certainty of success or recovery of our related expenses. Furthermore, even after an extensive qualification process, our products may fail to meet the standards sought by our end-use customers and may not be qualified for use by such end-use customers. Such a failure to qualify may result in us losing such companies as end-users of our products, which would cause a decrease in our revenue or revenue growth rate either of which could materially adversely affect our business and results of operations.

We may enter into agreements that may limit our ability to broadly market our products or could involve future obligations, which could make it more difficult for us to commercialize certain of our products and negatively affect our business and results of operations.

In order to commercialize our products, we may enter into commercial arrangements with distributors, OEMs or other customers. These agreements have contained, and may in the future contain, exclusivity, ownership and other terms that may limit our ability to commercialize any products or technology developed in connection with such agreements, including in ways that we do not envision at the time of entering into the agreement. These agreements may contain technical specifications or minimum volumes that must be achieved. However, these agreements may not obligate either party to make any purchases. As a result, our ability to commercialize products in a certain region or for a certain application may be limited and as a consequence our business, financial condition and results of operations could be materially adversely affected.

We are exposed to the credit risk of some of our direct customers, including distributors, contractors and OEMs, which subjects us to the risk of non-payment for our products.

We distribute our products through a network of distributors, contractors and OEMs, some of which may not be well-capitalized and may be of a lower credit quality. This direct customer network subjects us to the risk

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of non-payment for our products. Although we have not experienced a significant incidence of non-payment for our products, such non-payments may occur in the future. In addition, during periods of economic downturn in the global economy, our exposure to credit risks from our direct customers may increase, and our efforts to monitor and mitigate the associated risks may not be effective. In the event of non-payment by one or more of our direct customers, our business, financial condition and results of operations could be materially adversely affected.

Our working capital requirements involve estimates based on demand and production expectations and may decrease or increase beyond those currently anticipated, which could harm our results of operations and financial condition.

In order to fulfill the product delivery requirements of our direct and end-use customers, we plan for working capital needs in advance of customer orders. As a result, we base our funding and inventory decisions on estimates of future demand. If demand for our products does not increase as quickly as we have estimated or drops off sharply, our inventory and expenses could rise, and our business and results of operations could suffer. Alternatively, if we experience sales in excess of our estimates, our working capital needs may be higher than those currently anticipated. Our ability to meet this excess customer demand depends on our ability to arrange for additional financing for any ongoing working capital shortages, since it is likely that cash flow from sales will lag behind these investment requirements. To meet any ongoing working capital shortages, we may rely on our revolving credit facility; however, the credit available under this facility at any given time may not be able to meet our needs for working capital. In addition, the facility will mature on July 27, 2014 and we may not be able to extend or replace the facility upon expiration. See “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Liquidity and Capital Resources.” In addition, we plan to increase our inventory in order to meet our expected future demand. This would result in an increase in our working capital requirements that could harm our results of operations and financial condition.

Breakdowns, security breaches and other disruptions of our information technology systems could compromise our information and expose us to liability, which would cause our business and reputation to suffer.

In the ordinary course of our business, we collect and store sensitive data, including intellectual property, our proprietary business information and that of our suppliers, customers and business partners, and personally identifiable information. The secure maintenance of this information is critical to our operations and business strategy. Despite our security measures, our information technology and infrastructure may be vulnerable to breakdowns, attacks by hackers or breaches due to employee error, malfeasance or other disruptions. Any such breakdown or breach could compromise our networks and the information stored there could be accessed, publicly disclosed, lost or stolen. There can be no assurance that our management or diligence efforts will prevent such breakdowns or breaches in our systems. Any such access, disclosure or other loss of information could result in legal claims or proceedings, liability under laws that protect the privacy of personal information or other laws, disrupt our operations and damage our reputation, which could adversely affect our business.

We may incur significant costs complying with environmental laws and related claims, and failure to comply with these laws and regulations could expose us to significant liabilities, which could adversely affect our results of operations.

Costs of compliance with regional, national, state and local existing and future environmental laws and regulations could adversely affect our cash flow and results of operations. We are required to comply with numerous environmental laws and regulations and to obtain numerous governmental permits in order to operate our facilities and in connection with the design, development, manufacture and transport of our products and the storage, use, handling and disposal of hazardous substances, including environmental laws, regulations and permits governing air emissions. We may incur significant additional costs to comply with these requirements. If we fail to comply with these requirements, we could be subject to civil or criminal liability, damages and fines, and our operations could be curtailed or suspended. In addition, certain foreign laws and regulations may affect our ability to export products outside of the United States. Existing environmental laws and regulations could be revised or

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reinterpreted and new laws and regulations could be adopted or become applicable to us or our products, and future changes in environmental laws and regulations could occur. These factors may materially increase the amount we must invest to bring our processes into compliance and impose additional expense on our operations.

Among the changes to environmental laws and regulations that could occur is the adoption of regulatory frameworks to reduce greenhouse gas emissions, which a number of countries, particularly in the European Union, have adopted, or are considering adopting. These include adoption of cap and trade regimes, carbon taxes, restrictive permitting, increased efficiency standards, and incentives or mandates for renewable energy, any of which could increase the costs of manufacturing our products and increase our compliance costs, which could materially adversely affect our business and results of operations.

In addition, private lawsuits, including claims for remediation of contamination, personal injury or property damage, or actions by regional, national, state and local regulatory agencies, including enforcement or cost-recovery actions, may materially increase our costs. Certain environmental laws make us potentially liable on a joint and several basis for the remediation of contamination at or emanating from properties or facilities we currently or formerly owned or operated or properties to which we arranged for the disposal of hazardous substances. Such liability may require us to pay more than our fair share and could require us to address contamination caused by others. For example, the site of our East Providence facility contains certain levels of contamination caused by prior third-party activities on and near the site. Such contamination remains in place under a state-approved deed restriction, and we are required to comply with such deed restriction and the accompanying soil management plan. In general, the deed restriction prohibits the residential use of the property and the use of groundwater as potable water, and requires the maintenance of engineering controls and annual inspections to help prevent exposure to contaminated soils. The soil management plan requires us to notify the state environmental agency with respect to any soil excavation, stockpiling, sampling and off-site disposal of excavated soil. Although we have not had to make material expenditures to satisfy these requirements to date, in the future, we may incur additional costs to comply with these requirements and failure to do so could disrupt the operation of our facility or could subject us to liability for environmental remediation. We may incur liability relating to the remediation of contamination, including contamination we did not cause.

We may not be able to obtain or maintain, from time to time, all required environmental regulatory approvals. A delay in obtaining any required environmental regulatory approvals or failure to obtain and comply with them could materially adversely affect our business and results of operations.

We may face certain product liability or warranty claims from our products, including from improper installation of our products by third parties. As a consequence, we could lose existing and future business and our ability to develop, market and sell our insulation could be harmed.

The design, development, production and sale of our products involve an inherent risk of product liability claims and associated adverse publicity. We may be named directly in product liability suits relating to our products, even for defects resulting from errors of our distributors, contractors, OEMs or end-use customers. These claims could be brought by various parties, including distributors, contactors, OEMs and other direct end-use customers who are purchasing products directly from us, or end-use customers who purchase our products from our distributors. We could also be named as co-parties in product liability suits that are brought against the distributors, contractors, OEMs and end-use customers. Our products are often installed in our end-use customers’ complex and capital intensive facilities in inherently hazardous or dangerous environments, including in the energy, petrochemical and power generation industries, where the potential liability from risk of loss could be substantial. The failure of our products to perform to customer expectations, whether or not because of improper installation, could give rise to warranty claims against us. We are currently taking steps to educate our distributors, contractors, OEMs and end-use customers about the proper installation procedures to mitigate the risk of an uncontrolled burn-in for very high temperature applications of Pyrogel XT and XT-E. However, installation of our products is handled by third parties over whom we have no control and errors or defects in their installation may also give rise to claims against us, diminish our brand or divert our resources from other purposes. Any of these claims, even if without merit, could result in costly litigation or divert management’s

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attention and resources. In addition, many of our products are integrated into the final products of our customers. The integration of our products may entail the risk of product liability or warranty claims based on malfunctions or hazards from both our products and the final products of our customers.

A material product liability claim may seriously harm our results of operations, as well as damage our customer relationships and reputation. Although we carry general liability insurance, our current insurance coverage could be insufficient to protect us from all liability that may be imposed under these types of claims. Insurance coverage is expensive, may be difficult to obtain and may not be available in the future on acceptable terms or at all. Our distributors, contractors, OEMs and end-use customers may not have adequate insurance coverage to cover against potential claims. This insurance may not provide adequate coverage against potential losses, and if claims or losses exceed our liability insurance coverage, we may go out of business. In addition, insurance coverage may become more expensive, which would harm our results of operations.

Our contracts with U.S. government agencies may subject us to audits, criminal penalties, sanctions and other expenses and fines.

We perform contract research services for U.S. government agencies and our products are sold to customers that may incorporate them into government projects. U.S. government agencies, including the Defense Contract Audit Agency and the Department of Labor, routinely audit government contractors. These agencies review a contractor’s compliance with contract terms and conditions, performance under its contracts, cost structure and compliance with applicable laws, regulations and standards. The U.S. government also may review the adequacy of a contractor’s systems and policies, including a contractor’s purchasing, property, estimating, billing, accounting, compensation and management information systems. Any costs found to be overcharged or improperly allocated to a specific contract or any amounts improperly billed or charged for products or services will be subject to reimbursement to the government. As a government contractor, we are required to disclose to the U.S. government credible evidence of certain violations of law and contract overpayments. If we are found to have participated in improper or illegal activities, we may be subject to civil and criminal penalties and administrative sanctions, including termination of contracts, forfeiture of profits, suspension of payments, fines and suspension or prohibition from doing business with the U.S. government. Any negative publicity related to such contracts, regardless of the accuracy of such publicity, may adversely affect our business or reputation.

Our contracts with U.S. government agencies may not be funded by future appropriations and are subject to modification or termination at any time prior to their completion.

Our contracts with U.S. government agencies are subject to the availability of appropriated funds. The U.S. government funds our contract research work through a variety of funding programs that rely on monies appropriated by Congress. At any point, the availability of funding could change, thus reducing the opportunities for new or continued revenues to us from government contract work. Revenue from contracts with U.S. government agencies constituted 7.0%, 4.8% and 4.7% of total revenue in 2011, 2012 and 2013, respectively. We expect that our revenue under such contracts will continue to decline due to the recent trend toward tightening of federal spending guidelines and programs.

In addition, under our contracts, the U.S. government generally has the right not to exercise options to extend or expand our contracts and may modify, curtail or terminate the contracts at its convenience. Our government customers may not renew our existing contracts after the conclusion of their terms and we may not be able to enter into new contracts with U.S. government agencies. Any decision by the U.S. government not to exercise contract options or to modify, curtail or terminate our contracts or not to renew our contracts or enter into new contracts with us would adversely affect our revenues.

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Our revolving credit facility and subordinated notes contain financial and operating restrictions that may limit our access to credit. If we fail to comply with covenants in our revolving credit facility or subordinated notes, we may be required to repay our indebtedness thereunder, which may have an adverse effect on our liquidity.

Provisions governing our revolving credit facility and our subordinated notes each impose restrictions on our ability to operate, including, for some of the agreements and instruments, but not for others, our ability to:

• incur additional debt;

• pay dividends and make distributions;

• redeem or repurchase capital stock;

• create liens;

• enter into transactions with affiliates; and

• merge or consolidate with or into other entities.

Our revolving credit facility and subordinated notes also contain other customary covenants. We may not be able to comply with these covenants in the future. Our failure to comply with these covenants may result in the declaration of an event of default and could cause us to be unable to borrow funds under our revolving credit facility. In addition to preventing additional borrowings under our revolving credit facility, an event of default, if not cured or waived, may result in the acceleration of the maturity of indebtedness outstanding under the revolving credit facility, subordinated notes and convertible notes, which would require us to pay all amounts outstanding. Such an event may also lead our lenders to exercise their security interest in our assets, including all of our intellectual property and all of our real property and equipment at our East Providence facility. If an event of default occurs, we may not be able to cure it within any applicable cure period, if at all. If the maturity of our indebtedness is accelerated, we may not have sufficient funds available for repayment or we may not have the ability to borrow or obtain sufficient funds to replace the accelerated indebtedness on terms acceptable to us, or at all. We intend to use a portion of the proceeds from this offering to repay our subordinated notes and amounts outstanding under our revolving credit facility.

If we lose key personnel upon whom we are dependent, or if we are unable to successfully recruit and retain skilled employees, we may not be able to manage our operations and meet our strategic objectives.

Our continued success depends to a considerable degree upon the continued services of a small number of our employees with critical knowledge of our products, our manufacturing process, our intellectual property, our customers and our global operations. The loss or unavailability of any of these individuals could harm our ability to execute our business plan, maintain important business relationships and complete certain product development initiatives, which could harm our business. In the event that any of these key individuals leave their employment with us or take new employment with a competitor, our business and results of operations could be materially adversely affected. In addition, our continued success depends upon the availability, contributions, vision, skills, experience and effort of our senior management, financial, sales and marketing, engineering and production teams. We do not maintain “key person” insurance on any of our employees. We have entered into employment agreements with certain members of our senior management team, but none of these agreements guarantees the services of the individual for a specified period of time. All of the agreements with members of our senior management team provide that employment is at-will and may be terminated by the employee at any time and without notice.

Although we do not have any reason to believe that we may lose the services of any our employees with critical knowledge of our products, our manufacturing processes, our customers and our global operations or any of our senior management, financial, sales and marketing, engineering and production teams in the foreseeable future, the loss of the services of any of these individuals might impede our operations or the achievement of our strategic and financial objectives. The loss or interruption of the service of any of these individuals or our

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inability to attract or retain other qualified personnel or advisors could have a material adverse effect on our business, financial condition and results of operations and could significantly reduce our ability to manage our operations and implement our strategy.

Our ability to use our net operating loss carryforwards may be subject to limitation, which could result in a higher effective tax rate and adversely affect our financial condition and results of operations.

We performed analyses pursuant to Internal Revenue Code Section 382, as well as similar state provisions, in order to determine whether any limitations might exist on the utilization of net operating losses and other tax attributes. Based on these analyses, we determined that it is more likely than not that an ownership change occurred on June 10, 2008, resulting in an annual limitation on the use of our net operating losses and other tax attributes as of such date. Generally, a change of more than 50% in the ownership of a company’s stock, by value, over a three year period constitutes an ownership change for U.S. federal income tax purposes. An ownership change may limit a company’s ability to use its net operating loss carryforwards attributable to the period prior to such change. We also determined that we had built-in gains of $29.5 million at the date of that ownership change. Built-in gains increase the limitation under the Internal Revenue Code Section 382 to the extent triggered during the five year period subsequent to the date of change, which period ended in June 2013. As a result, the entire $29.5 million of net operating losses expired unutilized in June 2013.

At December 31, 2013, we had $173.3 million of net operating losses available to offset future federal income, if any, which expire on various dates through December 31, 2033. We expect to have another ownership change occur in connection with this offering. Accordingly, we expect a significant portion of these net operating losses will likely expire unutilized.

Risks Related to Our Intellectual Property

Our inability to protect our intellectual property rights could negatively affect our business and results of operations.

Our ability to compete effectively depends in part upon developing, maintaining and/or protecting intellectual property rights relevant to our aerogel product forms, applications, manufacturing technologies and brand names. We rely principally on a combination of patent protection, trade secret laws, confidentiality and nondisclosure agreements, trademark registrations, common law rights and licensing arrangements to establish and protect the intellectual property rights relevant to our business. However, these measures may not be adequate in every given case to permit us to gain or keep any competitive advantage, particularly in those countries where the laws do not protect our proprietary rights as fully as or where the enforcement tools are weaker or less effective than those in the United States. In particular, since aerogels were developed approximately 80 years ago, there has been a wide range of research, development and publication related to aerogels, which makes it difficult to establish intellectual property rights to many key elements of aerogel technology and to obtain patent protection. Accordingly, much of the general technology that we use in our manufacture of aerogel blankets is not protected by patents.

Where we consider it appropriate, our strategy is to seek patent protection in the United States and other countries on technologies used in or relating to our aerogel product forms, applications and manufacturing technologies. As of April 15, 2014, we had 21 issued U.S. patents and 30 issued foreign patents, including two U.S. patents and one European patent that we co-own with third parties. The issuance of a patent is not conclusive as to its scope, validity or enforceability. Thus, any patent held by us or to be issued to us from a pending patent application, could be challenged, invalidated or held unenforceable in litigation or proceedings before the U.S. Patent and Trademark Office and/or other patent tribunals. Third parties could develop technologies that circumvent the patent protection we have secured. No consistent policy regarding the breadth of patent claims has emerged to date in the United States and the landscape could become more uncertain in view of future rule changes by the United States Patent and Trademark Office, the introduction of patent reform legislation and decisions in patent law cases by the federal courts including the United States Supreme Court.

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The patent landscape outside the United States is even less predictable. As a result, the validity and enforceability of patents cannot be predicted with certainty. For example, we are aware of competitors that manufacture and market aerogel insulation products in China, where it may be difficult for us to enforce our intellectual property rights against these or other competitors. In addition, we may fail to apply for patents on important technologies or product candidates in a timely fashion, if at all, and our existing and future patents may not be sufficiently broad to prevent others from practicing our technologies or from developing competing products or technologies, in particular given the long history of aerogel development. Furthermore, third parties could practice our intellectual property rights in territories where we do not have patent protection. Such third parties may then try to import products made using our intellectual property rights into the United States or other countries. Our strategy is to seek registration of trademarks for our brands in many, but not all of the jurisdictions in which we sell our products based on various factors, including our sales volumes in the jurisdiction, our ability to enforce local laws and cost. Our strategy may not be adequate to protect our brands in all circumstances, especially in foreign jurisdictions.

As of April 15, 2014, we had 13 pending U.S. patent applications and 5 pending foreign patent applications, as well as a family of pending foreign patent applications that we co-own with another third party. Our pending patent applications are directed to various enabling technologies for the product forms, applications and manufacturing technologies that support our current business, as well as aspects of products under development or contemplated for the future. The issuance of patents from these applications involves complex legal and factual questions and, thus, we cannot assure you that any of our pending patent applications will result in the issuance of patents to us. The U.S. Patent and Trademark Office, relevant foreign patent offices and other relevant patent tribunals may deny or require significant narrowing of claims in our pending patent applications. Patents issued as a result of any of our pending patent applications may not cover our enabling technology and/or the products or processes that support our current or future business or afford us with significant commercial protection against others with similar technology. Proceedings before the U.S. Patent and Trademark Office could result in adverse decisions as to the priority of our inventions and the narrowing or invalidation of claims in issued patents. In addition, our pending patent applications filed in foreign countries are subject to laws, rules and procedures that differ from those of the United States, and thus foreign patent applications may not be granted even if counterpart United States patents are issued.

Patents covering technologies that are similar or superior to our technologies may be developed or obtained by third parties. We may need to seek licenses to these technologies, which could limit our ability to manufacture our products and have a material adverse effect on our business and results of operations.

Competitors or other third parties may independently develop and obtain patents covering technologies that are similar or superior to the product forms, applications or manufacturing technologies that we employ. In such event, we may need to obtain licenses for these technologies. However, we may not be able to obtain licenses on reasonable terms, if at all, which could limit our ability to manufacture our current and/or future products and operate our business.

Our contracts with the U.S. government and other third parties could negatively affect our intellectual property rights.

To further our product development efforts, our scientists and engineers work closely with customers, the U.S. government and other third parties to research and develop advancements in aerogel product forms, applications and manufacturing technologies. We have entered into agreements with private third parties and have been awarded numerous research contracts with the U.S. government to independently or jointly research, design and develop new devices and systems that incorporate aerogel material. We also expect to enter into similar private agreements and be awarded similar government contracts in the future. In some instances, the research and development activities that we conduct under contract with the U.S. government and/or with private third parties may produce intellectual property to which we may not have ownership or exclusive rights and will be unable to protect or monetize.

Moreover, when we develop new technologies using U.S. government funding, the government may obtain certain rights in any resulting patents, technical data and/or other confidential and proprietary information,

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generally including, at a minimum, a non-exclusive license authorizing the U.S. government to use the invention, technical data or software for non-commercial purposes. This federal government funding may limit when and how we can deploy our technology developed under those contracts. In addition, inventions must be reported promptly to the funding agencies, the federal funding must be disclosed in any resulting patent applications, and our rights in such inventions will normally be subject to government license rights, periodic post-contract utilization reporting, foreign manufacturing restrictions and “march-in” rights. March-in rights refer to the right of the U.S. government to require us to grant a license to the technology to a responsible applicant or, if we refuse, the government may grant the license itself. The U.S. government may exercise its march-in rights if it determines that action is necessary because we fail to achieve practical application of any technology developed under contract with the government or because action is necessary to alleviate health or safety needs, to meet requirements of federal regulations or to give preference to United States industry. The U.S. government may also have the right to disclose our confidential and proprietary information to third parties. In addition, failure to comply with all the government contract requirements may result in us losing the patent rights.

Our U.S. government-sponsored research contracts are also subject to audit and require that we provide regular written technical updates on a monthly, quarterly or annual basis, and, at the conclusion of the research contract, a final report on the results of our technical research. Because these reports are generally available to the public, third parties may obtain some aspects of our confidential and proprietary information relating to our product forms, applications and/or manufacturing processes. If we fail to provide these reports or to provide accurate or complete reports, the U.S. government could obtain rights to any intellectual property arising from the related research.

Furthermore, there could be disputes between us and a private third party as to the ownership rights to any inventions that we develop in collaboration with such third party. Any such dispute may cause us to incur substantial costs, and could place a significant strain on our financial resources, divert the attention of management from our core business and harm our reputation.

We rely on trade secrets to protect our technology, and our failure to obtain or maintain trade secret protection could adversely affect our competitive business position.

We rely in part on trade secret protection to protect confidential and proprietary information relating to our technology, particularly where we do not believe patent protection is appropriate or obtainable. We continue to develop and refine the manufacturing technologies used to produce our aerogel products and believe that we have already developed, and will continue to develop, significant know-how related to these technologies. However, trade secrets can be difficult to protect. We may not be able to maintain the secrecy of this information and competitors may develop or acquire equally or more valuable information related to the manufacture of comparable aerogel products. Our strategy for scale-up of commercial production will continue to require us to share confidential and proprietary information with the U.S. government and other third parties. While we take reasonable efforts to protect our trade secrets, our employees, consultants, contractors or scientific and other advisors, or those of our business partners, may intentionally or inadvertently disclose our confidential and proprietary information to competitors. Any enforcement of claims by us that a third party has obtained and is using our trade secrets is expensive, time consuming and uncertain. In addition, foreign courts are sometimes less willing than United States courts to protect trade secrets.

We require all employees and consultants to execute confidentiality and/or nondisclosure agreements upon the commencement of an employment or consulting arrangement with us, which agreements generally require that all confidential and proprietary information developed by the individual or made known to the individual by us during the course of the individual’s relationship with us be kept confidential and not disclosed to third parties. These agreements further generally provide that inventions conceived by the individual in the course of rendering services to us will be our exclusive property. Nevertheless, these agreements may not be honored and our confidential and proprietary information may be disclosed, or these agreements may be unenforceable or difficult to enforce. We also require customers and vendors to execute confidentiality and/or nondisclosure

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agreements. However, we have not obtained such agreements from all of our customers and vendors. Moreover, some of our customers may be subject to laws and regulations that require them to disclose information that we would otherwise seek to keep confidential. Our confidential and proprietary information may be otherwise disclosed without our authorization or knowledge. Moreover, third parties could reverse engineer our manufacturing processes, independently develop substantially equivalent confidential and proprietary information or otherwise gain access to our trade secrets. Failure to maintain trade secret protection could enable others to produce competing products and adversely affect our competitive business position.

We could become subject to intellectual property litigation that could be costly, limit or invalidate our intellectual property rights, divert time and efforts away from business operation, require us to pay damages and/or otherwise have an adverse material impact on our business.

The success of our business is highly dependent on protecting our intellectual property rights. Unauthorized parties may attempt to copy or otherwise obtain and use our products and/or enabling technology. Policing the unauthorized use of our intellectual property rights is difficult and expensive, as is enforcing these rights against unauthorized use by others. Identifying unauthorized use of our intellectual property rights is difficult because we may be unable to monitor the technologies and/or materials being employed by other parties. The steps we have taken or will take may not prevent unauthorized use of our intellectual property rights, particularly in foreign countries where enforcement of intellectual property rights may be more difficult than in the United States.

Our continued commercial success will also depend in part upon not infringing the patents or violating other intellectual property rights of third parties. We are aware of patents and patent applications generally relating to aspects of our technologies filed by, and issued to, third parties. Our knowledge of the patent landscape with respect to the technologies currently embodied within our aerogel products and the technologies that we practice in manufacturing those products indicates that the third-party patent rights most relevant to our business are those owned by Cabot and licensed to us under the cross license agreement with Cabot. Nevertheless, we cannot determine with certainty whether patents or patent applications of other parties may materially affect our ability to conduct our business. There may be existing patents of which we are unaware that we may inadvertently infringe, resulting in claims against us or our customers. In recent years, Chinese and Japanese entities have filed significantly more application patents related to aerogel products in both their home countries and in foreign countries. These application patents may make it more difficult for OEMs and end-use customers in these countries to use our products in new and different applications, which in turn may limit our ability to penetrate new markets.

In the event that the manufacture, use and/or sale of our products or technologies is challenged, or if our product forms or technologies conflict with patent rights of others or our operations conflict with trademark or similar rights of others, third parties could bring legal actions against us in the United States, Europe or other countries, claiming damages and seeking to enjoin the manufacturing and/or marketing of our products. In addition, it is not possible to predict with certainty what patent claims may arise from pending patent applications of third parties. In the United States, for example, patent prosecution can proceed in secret prior to issuance of a patent, provided such application is not filed in a foreign jurisdiction. For U.S. patent applications that are also filed in foreign jurisdictions, such patent applications will not be published until 18 months from the filing date of the application. As a result, third parties may be able to obtain patents with claims relating to our product forms, applications and/or manufacturing processes which they could attempt to assert against us or our end-users. In either case, litigation may be necessary to enforce, protect or defend our intellectual property rights or to determine the validity and scope of the intellectual property rights of others. Any such litigation could be unsuccessful, cause us to incur substantial costs, divert resources and the efforts of our personnel away from daily operations, harm our reputation and/or result in the impairment of our intellectual property rights. In some cases, litigation may be threatened or brought by a patent holding company (otherwise known as non-practicing entities or patent “trolls”) or other adverse patent owner who has no relevant product revenues and against which our patents may provide little or no deterrence. If we are found to infringe any patents, we could be required to:

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• pay substantial monetary damages, including lost profits, reasonable royalties and/or treble damages if an infringement is found to be willful;

• totally discontinue or substantially modify any products or processes that are found to be in violation of another party’s intellectual property rights; and/or

• seek a license to continue making and selling our products and/or using our manufacturing processes, which we may not be able to obtain on reasonable terms, if at all, which could significantly increase our operating expenses and/or decrease our revenue.

If our competitors are able to use our technology without payment to us, our ability to compete effectively could be harmed. Our contracts generally indemnify our customers for third-party claims of intellectual property infringement related to our manufacture of the products, and typically up to the amount of the purchase price paid for the product. The expense of defending these claims may adversely affect our results of operations.

Loss of the intellectual property rights that we license from Cabot Corporation would have a material adverse impact on our business.

We have licensed certain intellectual property rights from Cabot under a cross license agreement. These intellectual property rights have been and continue to be critical to the manufacture of our existing products and may also be important to our research, development and manufacture of new products. Any loss of the intellectual property rights granted to us thereunder, including as a result of ineffective protection of such rights by Cabot or a breach of or dispute under the agreement by either party would have a material adverse impact on our financial condition, results of operations and growth prospects, and might prevent us from continuing our business. For a more detailed description of the cross license agreement with Cabot, see “Business — Intellectual Property — Cross License Agreement with Cabot Corporation.”

Risks Related to Our Common Stock and This Offering

We will incur costs and demands upon management as a result of complying with the laws and regulations affecting public companies in the United States, which may adversely affect our results of operations.

After the consummation of this offering, we will be subject to the reporting requirements of the Exchange Act that require us to file, among other things, quarterly reports on Form 10-Q and annual reports on Form 10-K. Under Section 302 of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act”), as a part of each of these reports, our chief executive officer and chief financial officer will be required to evaluate and report their conclusions regarding the effectiveness of our disclosure controls and procedures and to certify that they have done so. This requirement will apply to our first Form 10-Q for the quarter following effectiveness of the registration statement. Effective internal controls are necessary for us to provide reliable financial reports and prevent fraud. In addition, under Section 404 of the Sarbanes-Oxley Act, we will be required to include a report of management on our internal control over financial reporting in our Form 10-K. This requirement will first apply to our Form 10-K for our fiscal year ended December 31, 2015. In addition, upon the later of our second annual report or the first annual report required to be filed with the SEC following the date we are no longer an “emerging growth company” as defined in the JOBS Act, the independent registered public accounting firm auditing our financial statements will be required to attest to and report on the effectiveness of our internal control over financial reporting. The process of improving our internal controls and complying with Section 404 will be expensive and time consuming, and will require significant attention of management.

Complying with these and other requirements applicable to public companies may place a strain on our personnel, information technology systems and resources and divert management’s attention from other business concerns. We may need to hire additional accounting and financial staff with appropriate public company experience and technical accounting knowledge, and we may not be able to do so without incurring additional costs.

These and other requirements may also make it more difficult or more costly for us to obtain certain types of insurance, including directors’ and officers’ liability insurance. We may be forced to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage.

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The impact of these requirements could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors, our board committees or as executive officers. Any one of these requirements could have a material adverse effect on our business, financial condition and results of operations.

As a result of becoming a public company, we will be obligated to develop and maintain proper and effective internal control over financial reporting. If our internal controls over financial reporting are determined to be ineffective, or if our auditors are otherwise unable to attest to their effectiveness when required, investor confidence in our company, and our common stock price, may be adversely affected.

We will be required, pursuant to Section 404 of the Sarbanes-Oxley Act, to furnish a report by management on, among other things, the effectiveness of our internal control over financial reporting for the first fiscal year beginning after the effective date of this offering, which would be for the fiscal year ended December 31, 2015, and in each year thereafter. Our independent registered public accounting firm will not be required to formally attest to the effectiveness of our internal control over financial reporting until the later of our second annual report or the first annual report required to be filed with the SEC following the date we are no longer an “emerging growth company,” as defined in the JOBS Act. These assessments will be required to include disclosure of any material weaknesses identified by our management in our internal control over financial reporting.

Although our independent registered public accounting firm did not complete an audit of internal controls over financial reporting as of December 31, 2013, one significant deficiency in internal controls was identified in connection with the preparation of our financial statements. In light of our becoming a public company, we determined that we had a significant deficiency relating to our need for additional accounting and financial reporting staff. We have taken actions to remediate this significant deficiency, including hiring external consultants to provide additional resources in connection with the 2013 year-end and commencing the hiring process for additional full-time financial and accounting staff. We cannot assure you that there will not be material weaknesses or other significant deficiencies in our internal controls in the future.

We are in the very early stages of the costly and challenging process of compiling our system of internal controls over financial reporting and processing documentation necessary to perform the evaluation needed to comply with Section 404. We may discover, and not be able to remediate, future significant deficiencies or material weaknesses. We may not be able to complete our evaluation, testing and any required remediation in a timely fashion, any of which would make us less likely to detect or prevent fraud. During the evaluation and testing process, if we identify one or more material weaknesses in our internal control over financial reporting, we will be unable to assert that our internal controls are effective. If we are unable to assert that our internal controls over financial reporting are effective, we could lose investor confidence in the accuracy and completeness of our financial reports or it could cause us to fail to meet our reporting obligations, which could have a material adverse effect on the price of our common stock. In addition, a delay in compliance with Section 404 could subject us to a variety of administrative sanctions, including SEC action, ineligibility for short form resale registration, the suspension or delisting of our common stock from The New York Stock Exchange, and the inability of registered broker-dealers to make a market in our common stock, which would further reduce our stock price and could harm our business.

We are eligible to be treated as an “emerging growth company” as defined in the JOBS Act, and we cannot be certain if the reduced disclosure requirements applicable to emerging growth companies will make our common stock less attractive to investors.

We are an “emerging growth company”, as defined in the JOBS Act. For as long as we continue to be an emerging growth company, we may take advantage of exemptions from various reporting requirements that are applicable to other public companies that are not emerging growth companies, including:

• not being required to comply with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act, as described above;

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• reduced disclosure obligations regarding executive compensation in this prospectus and our periodic reports and proxy statements; and

• exemptions from the requirements of holding a nonbinding advisory vote on executive compensation and stockholder approval of any golden parachute payments not previously approved.

We will remain an emerging growth company until the earliest to occur of (i) the end of the fiscal year for which we report $1.0 billion or more in annual revenues, (ii) the end of the fiscal year in which the market value of our common stock held by non-affiliates exceeds $700 million on the last business day of our second fiscal quarter, (iii) our issuance, in a three year period, of more than $1.0 billion of non-convertible debt, and (iv) December 31, 2019. Even after we no longer qualify as an emerging growth company, we may still qualify as a “smaller reporting company” which would allow us to take advantage of many of the same exemptions from disclosure requirements, including not being required to complying with the auditor attestation requirements of Section 404 of the Sarbanes-Oxley Act and reduced disclosure obligations regarding executive compensation in our periodic reports and proxy statements. We cannot predict if investors will find our common stock less attractive because we may rely on these exemptions. If some investors find our common stock less attractive as a result, there may be a less active trading market for our common stock and our stock price may be more volatile.

There has been no prior public market for our common stock and an active trading market may not develop.

Prior to this offering, there has never been a public market for our common stock. A liquid trading market for our common stock may not develop. We cannot predict when or whether investor interest in our common stock on the NYSE might lead to an increase in market price or the development of a more active trading market or how liquid that market might become. If an active market for our securities does not develop, it may be difficult to sell common stock you purchase in this offering. An inactive market may also impair our ability to raise capital by selling our common stock and may impair our ability to acquire other companies, products or technologies by using our common stock as consideration.

We expect that the price of our common stock will fluctuate substantially and you may not be able to sell your shares at or above the initial public offering price.

The initial public offering price of our common stock sold in this offering was determined by negotiation between the representatives of the underwriters and us. This price may not reflect the market price of our common stock that will prevail in the trading market following this offering. You may not be able to resell your shares at or above the initial public offering price due to a number of factors, including those listed in “— Risks Related to Our Business and Strategy” and including the following, some of which are beyond our control:

• volume and timing of orders for our products;

• quarterly and yearly variations in our or our competitors’ results of operations;

• our announcement or our competitors’ announcements regarding new products, product enhancements, significant contracts, number of distributors, acquisitions or strategic investments;

• announcements of technological innovations relating to aerogels, thermal management and energy infrastructure insulation;

• results of operations that vary from the expectations of securities analysts and investors;

• the periodic nature of our sales cycles, in particular for capital projects in the industrial markets;

• our ability to develop, obtain regulatory clearance or approval for and market new and enhanced products on a timely basis;

• future sales of our common stock, including sales by our executive officers, directors and significant stockholders;

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• announcements by third parties of significant claims or proceedings against us, including with regards to intellectual property and product liability;

• changes in accounting principles; and

• general U.S. and global economic conditions and other factors, including factors unrelated to our operating performance or the operating performance of our competitors.

Furthermore, the U.S. stock market has at times experienced extreme volatility that in some cases has been unrelated or disproportionate to the operating performance of particular companies. These broad market and industry fluctuations may adversely affect the market price of our common stock, regardless of our actual operating performance.

In the past, following periods of market volatility, stockholders have instituted securities class action litigation. If we were involved in securities litigation, it could have a substantial cost and divert resources and the attention of our senior management team from our business regardless of the outcome of such litigation.

Securities analysts may not initiate coverage of our common stock or may issue negative reports, which may have a negative impact on the market price of our common stock.

The trading market for our common stock will rely in part on the research and reports that industry or financial analysts publish about us or our business. Securities analysts may elect not to provide research coverage of our common stock after the completion of this offering. If securities analysts do not cover our common stock after the completion of this offering, the lack of research coverage may cause the market price of our common stock to decline. If one or more of the analysts who elects to cover us downgrades our stock, our stock price would likely decline substantially. If one or more of these analysts ceases coverage of us, we could lose visibility in the market, which in turn could cause our stock price to decline. In addition, rules mandated by the Sarbanes-Oxley Act and a global settlement reached in 2003 between the SEC, other regulatory agencies and a number of investment banks have led to a number of fundamental changes in how analysts are reviewed and compensated. In particular, many investment banking firms are required to contract with independent financial analysts for their stock research. It may be difficult for companies such as ours, with smaller market capitalizations, to attract independent financial analysts that will cover our common stock. This could have a negative effect on the market price of our stock.

Our directors, officers and principal stockholders have significant voting power and may take actions that may not be in the best interests of our other stockholders.

After this offering, our officers, directors and principal stockholders and their affiliates collectively will control approximately     % of our outstanding common stock (or     % if the underwriters exercise in full their option to purchase additional shares). As a result, these stockholders, if they act together, will be able to control the management and affairs of our company and most matters requiring stockholder approval, including the election of directors and approval of significant corporate transactions. This concentration of ownership may have the effect of delaying or preventing a change of control and might adversely affect the market price of our common stock. This concentration of ownership may not be in the best interests of our other stockholders.

Anti-takeover provisions in our restated certificate of incorporation and restated by-laws, and Delaware law, could delay or discourage a takeover.

Anti-takeover provisions in our restated certificate of incorporation and restated by-laws and Delaware law may have the effect of deterring or delaying attempts by our stockholders to remove or replace management, engage in proxy contests and effect changes in control. The provisions of our charter documents include:

• procedures for advance notification of stockholder nominations and proposals;

• the inability of our stockholders to call a special meeting of the stockholders and the inability of our stockholders to act by written consent;

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• the ability of our board of directors to create new directorships and to fill any vacancies on the board of directors;

• the ability of our board of directors to amend our restated by-laws without stockholder approval; and

• the ability of our board of directors to issue up to              shares of preferred stock without stockholder approval upon the terms and conditions and with the rights, privileges and preferences as our board of directors may determine.

In addition, as a Delaware corporation, we are subject to Delaware law, including Section 203 of the Delaware General Corporation Law. In general, Section 203 prohibits a Delaware corporation from engaging in any business combination with any interested stockholder for a period of three years following the date that the stockholder became an interested stockholder unless certain specific requirements are met as set forth in Section 203. These provisions, alone or together, could have the effect of deterring or delaying changes in incumbent management, proxy contests or changes in control. See “Description of Capital Stock.”

Our restated certificate of incorporation designates a state or federal court located within the State of Delaware as the exclusive forum for certain types of actions and proceedings that may be initiated by our stockholders, which could limit our stockholders’ ability to obtain a favorable judicial forum for disputes with us or our directors, officers of employees.

Our restated certificate of incorporation provides that, subject to limited exceptions, a state or federal court located within the State of Delaware will be the exclusive forum for (1) any derivative action or proceeding brought on our behalf, (2) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers or other employees to us or our stockholders, (3) any action asserting a claim against us arising pursuant to any provision of the Delaware General Corporation Law, our restated certificate of incorporation or our amended and restated by-laws, or (4) any other action asserting a claim against us that is governed by the internal affairs doctrine. Any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock shall be deemed to have notice of and to have consented to the provisions of our restated certificate of incorporation described above. This choice of forum provision may limit a stockholder’s ability to bring a claim in a judicial forum that it finds favorable for disputes with us or our directors, officers or other employees, which may discourage such lawsuits against us and our directors, officers and employees. Alternatively, if a court were to find these provisions of our restated certificate of incorporation inapplicable to, or unenforceable in respect of, one or more of the specified types of actions or proceedings, we may incur additional costs associated with resolving such matters in other jurisdictions, which could adversely affect our business and financial condition.

Future sales of our common stock or the possibility or perception of such future sales may depress our stock price and impair our ability to raise future capital through the sale of our equity securities.

Upon completion of the offering, our current stockholders will hold a substantial number of shares of our common stock that they will be able to sell in the public market in the near future. A significant portion of these shares will be held by a small number of stockholders. Sales by our current stockholders of a substantial number of shares after this offering, or the perception that these sales could occur, could significantly reduce the market price of our common stock. All the shares sold in this offering will be freely tradable. Substantially all of the remaining shares of our common stock are available for resale in the public market, subject to the restrictions on sale or transfer during the 180-day lockup period after the date of this prospectus that is described in “Shares Eligible for Future Sale.” Registration of the sale of these shares of our common stock would permit their sale into the market immediately. As restrictions on resale end or upon registration of any of these shares for resale, the market price of our common stock could drop significantly if the holders of these shares sell them or are perceived by the market as intending to sell them. These sales could also impede our ability to raise future capital.

Moreover, following the completion of this offering and including (i) any shares issued upon conversion of our preferred stock (including shares of Series C preferred stock issuable upon the assumed exercise of all of our

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outstanding warrants to purchase Series C preferred stock in connection with this offering) and (ii) any shares of common stock issuable upon the automatic conversion of all principal and accrued but unpaid interest on our convertible notes, each of which would occur upon the closing of the offering made hereby, the holders of approximately             shares of common stock, as well as approximately 99,354 shares underlying certain outstanding warrants to purchase our common stock, will have rights, subject to some conditions, to require us to include their shares in registration statements that we may file for ourselves or other stockholders. The              shares represent approximately     % of the total number of shares of our common stock to be outstanding immediately after this offering, assuming no exercise of the underwriters’ option to purchase additional shares. See “Description of Capital Stock — Registration Rights” for a description of the registration rights of these stockholders. By exercising their registration rights and selling a large number of shares, these holders could cause the prevailing market price of our common stock to decline.

As a new investor, you will experience immediate and substantial dilution in the net tangible book value of the shares you purchase in this offering.

The initial public offering price is substantially higher than the net tangible book value per share prior to the completion of this offering. Assuming an initial public offering price of our common stock of $         per share, the mid-point of the initial public offering price range set forth on the cover page of this prospectus, you will incur immediate dilution in net tangible book value per share of $        . This dilution is due in large part to earlier investors in our company having paid substantially less than the initial public offering price when they purchased their shares. Additionally, new investors in this offering will have contributed     % of our total equity as of                     , 2014, but will own only     % of our outstanding shares upon completion of this offering.

Since we require additional funds to develop new products and continue to expand our business, we may conduct substantial future offerings of equity securities. Future equity issuances, including future public offerings or future private placements of equity securities and any additional shares issued in connection with acquisitions, will result in further dilution to investors.

We do not intend to pay cash dividends in the foreseeable future and, consequently, your ability to achieve a return on your investment will depend on appreciation in the price of our common stock.

We have never declared or paid cash dividends on our common stock and we do not intend to pay any cash dividends on our common stock in the foreseeable future. We currently expect to retain all available funds and any future earnings for use in the operation and expansion of our business. In addition, the terms of our revolving credit facility and our subordinated notes restrict our ability to pay dividends and any future credit facilities, loan agreements, debt instruments or other agreements may further restrict our ability to pay dividends. Payments of future dividends, if any, will be at the discretion of our board of directors after taking into account various factors, including our business, results of operations and financial condition, current and anticipated cash needs, plans for expansion and any legal or contractual limitations on our ability to pay dividends. As a result, capital appreciation, if any, of our common stock will be your sole source of potential gain for the foreseeable future.

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SPECIAL NOTE REGARDING FORWARD LOOKING STATEMENTS

This prospectus contains forward-looking statements. All statements other than statements of historical facts contained in this prospectus, including statements regarding our strategy, future operations, future financial position, future revenue, projected costs, prospects, plans, objectives of management and expected market growth are forward-looking statements. These statements involve known and unknown risks, uncertainties and other important factors that may cause our actual results, performance or achievements to be materially different from any future results, performance or achievements expressed or implied by the forward-looking statements.

The words “anticipate,” “believe,” “could,” “estimate,” “expect,” “intend,” “may,” “plan,” “potential,” “predict,” “project,” “should,” “target,” “will,” “would” and similar expressions are intended to identify forward-looking statements, although not all forward-looking statements contain these identifying words. These forward-looking statements include, among other things, statements about:

• our expectations as to the future growth of our business;

• the expected future growth of the market for aerogel insulation, in particular in energy infrastructure facilities;

• our belief that our products possess strong competitive advantages over traditional insulation materials, including the superior thermal performance and the thin, easy-to-use and durable blanket form of our products;

• our expectation that our planned third production line will be completed in the first half of 2015, with the additional expenditures for the design, development and construction of this line totaling approximately $30 million;

• our expectation that our planned third production line will increase our capacity by 25% to 50 million to 55 million square feet of aerogel blankets;

• our plans to construct a second manufacturing facility in Europe or Asia, the location of which will be based on factors including labor and construction costs, availability of governmental incentives and proximity to raw material suppliers;

• our expectation that the first production line at the planned second manufacturing facility will become operational during 2017;

• our estimate that design, development and construction costs for this second manufacturing facility and its first production line will range from $80 million to $100 million;

• our expectation that our planned second manufacturing facility and its first production line will increase our annual nameplate capacity by 26 million to 28 million square feet of aerogel blankets;

• our belief that we can finance our planned second manufacturing facility and its first production line with, in addition to the proceeds from this offering, anticipated cash flows from operations, local government grants and debt financing;

• our belief that our aerogel products and manufacturing processes are proprietary and that we can protect our patents, trade secrets and know-how associated therewith;

• our belief that we can continue to improve the cost efficiency of our manufacturing process;

• our belief that our products have the lowest cost on a fully-installed basis or offer significant life-cycle cost savings in energy infrastructure and certain other applications as compared to traditional insulation materials;

• the expected future development of new aerogel technologies; and

• our expectations about limitations of net operating losses in connection with this offering.

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These forward looking statements are only predictions and we may not actually achieve the plans, intentions or expectations disclosed in our forward-looking statements, so you should not place undue reliance on our forward-looking statements. Actual results or events could differ materially from the plans, intentions and expectations disclosed in the forward-looking statements we make. We have based these forward-looking statements largely on our current expectations and projections about future events and trends that we believe may affect our business, financial condition and operating results. We have included important factors in the cautionary statements included in this prospectus, particularly in the “Risk Factors” section, that could cause actual future results or events to differ materially from the forward-looking statements that we make. Our forward-looking statements do not reflect the potential impact of any future acquisitions, mergers, dispositions, joint ventures or investments we may make.

Our forward-looking statements in this prospectus represent our views only as of the date of this prospectus. We disclaim any intent or obligation to update “forward-looking statements” made in this prospectus to reflect changed assumptions, the occurrence of unanticipated events or changes to future operating results over time. You should, therefore, not rely on these forward-looking statements as representing our views as of any date subsequent to the date of this prospectus.

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USE OF PROCEEDS

We estimate that we will receive net proceeds from this offering of approximately $         million, or approximately $         million if the underwriters exercise their option to purchase additional shares in full, based on an assumed initial public offering price of $         per share, which is the mid-point of the estimated price range set forth on the cover page of this prospectus, after deducting estimated underwriting discounts and estimated offering expenses payable by us.

A $1.00 increase (decrease) in the assumed initial public offering price of $         per share would increase (decrease) the net proceeds to us from this offering by $         million, assuming the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and after deducting estimated underwriting discounts and estimated offering expenses payable by us. An increase (decrease) of 1,000,000 shares from the expected number of shares to be sold in this offering, assuming no change in the assumed initial public offering price per share, would increase (decrease) our net proceeds from this offering by $         million.

We intend to use:

• approximately $30 million of the net proceeds we receive from this offering to fund the additional expenditures necessary for the design, development and construction of our third production line in East Providence;

• approximately $              million of the net proceeds to repay any amounts outstanding under our revolving line of credit, which matures on July 27, 2014 and bears interest at the greater of the prime rate or 4% (which at December 31, 2013 was 4% per annum and which is also the weighted average rate), plus 1.0% per annum, and approximately $19 million of the net proceeds to repay our subordinated notes due September 2014, which bear interest at a rate of 20% per annum; and

• the remaining net proceeds for general corporate purposes, which will include funding a portion of the design, development and construction of our planned second production plant in Europe or Asia after completion of our third production line.

We anticipate initial operation of a first production line at this second production plant during 2017. Based on our preliminary plans for this plant, our projected cost to construct an initial production line and plant infrastructure is $80 million to $100 million, of which we expect approximately $         million to $         million to be funded by the net proceeds of this offering. We expect that the remaining $         million to $         million required to construct an initial production line and plant infrastructure will be funded by anticipated cash flows from operations, local government grants and debt financings. See “Risk Factors—Risks Related to Our Business and Strategy—We will require significant additional capital to pursue our growth strategy beyond the construction of our third line in our East Providence facility, but we may not be able to obtain additional financing on acceptable terms or at all.”

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DIVIDEND POLICY

We have never declared or paid any dividends on our common stock. We currently intend to retain future earnings, if any, for use in the operation and expansion of our business and to finance our research and development efforts and do not anticipate declaring or paying cash dividends in the foreseeable future.

The convertible note purchase agreements related to the convertible notes, the revolving credit facility and the note purchase agreement related to the subordinated notes all contain restrictive covenants that restrict our ability to pay any dividends or make any distributions or payment on, or redeem, retire or repurchase, any capital stock. Our convertible notes will automatically convert into common stock with the consummation of this offering. We intend to repay our subordinated notes with a portion of the proceeds from this offering.

Any future determination to pay dividends will be at the discretion of our board of directors and will depend upon a number of factors, including our results of operations, financial condition, future prospects, contractual restrictions, restrictions imposed by applicable law and other factors our board of directors deems relevant.

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CAPITALIZATION

The following table sets forth our cash and capitalization as of December 31, 2013:

• on an actual basis;

• on an as adjusted basis (a) assuming the exercise for cash of all of our outstanding warrants to purchase Series C preferred stock and (b) giving effect upon the completion of this offering to;

• the automatic conversion of all shares of our preferred stock into             shares of our common stock;

• the automatic conversion of our convertible notes and all accrued but unpaid interest thereon into             shares of our common stock; and

• the sale of              shares of our common stock offered by us in this offering at an assumed initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, after deducting estimated underwriting discounts and estimated offering expenses payable by us and the use of a portion of the proceeds therefrom to repay all outstanding amounts under our revolving credit facility and under our subordinated notes due September 2014.

You should read this table together with our consolidated financial statements and the related notes thereto, as well as the information under “Selected Consolidated Financial Data” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” The as adjusted information below is prepared for illustrative purposes only and our capitalization following the completion of this offering will be adjusted based on the actual initial public offering price, the closing of the offering made hereby and other terms of the offering determined at pricing.

	As of December 31, 2013
	Actual			As adjusted
	(Unaudited) (In thousands, except share and per share data)
Cash(1)	$	1,574		$
Debt:
Capital leases	$	240		$
Revolving Credit Facility(2)		1,000
Subordinated Notes(2)		17,306
Convertible notes(3)		120,009
Total debt	$	138,555		$
Stockholders’ (deficit) equity:
Series A preferred stock, $0.00001 par value; 5,284,347 shares authorized, issued and outstanding, on an actual basis; no shares issued or outstanding, as adjusted		—
Series B preferred stock, $0.00001 par value; 1,601,053 shares authorized, issued and outstanding, on an actual basis; no shares issued or outstanding, as adjusted		—
Series C preferred stock, $0.00001 par value; 116,024,242 shares authorized, 20,000 shares issued and outstanding, on an actual basis; no shares issued or outstanding, as adjusted		—
Common stock, $0.00001 par value; 210,888,230 shares authorized, 2,623,156 shares issued and outstanding, on an actual basis; and              shares issued and outstanding, as adjusted(1)(3)(4)		—
Additional paid-in capital(1)(3)(4)		270,794
Accumulated deficit		(332,760	)
Total stockholders’ (deficit) equity	$	(61,966	)	$
Total capitalization	$	76,589		$

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(1) To the extent we change the number of shares of common stock sold by us in this offering from the shares we expect to sell or we change the initial public offering price from the $         per share assumed initial public offering price, representing the mid-point of the estimated price range set forth on the cover page of this prospectus, or any combination of these events occurs, the net proceeds to us from this offering and consequently the cash and each of additional paid-in capital, total stockholders’ equity and total capitalization may increase or decrease. A $1.00 increase (decrease) in the assumed initial public offering price per share of the common stock would increase (decrease) the net proceeds that we receive in this offering and each of our as adjusted cash, additional paid-in capital, total stockholders’ equity and total capitalization by approximately $         million, assuming that the number of shares offered by us under this prospectus remains the same. An increase (decrease) of 1,000,000 shares in the expected number of shares to be sold in the offering, assuming no change in the assumed initial public offering price per share, would increase (decrease) our net proceeds from this offering and consequently the cash and each of additional paid-in capital, total stockholders’ equity and total capitalization by approximately $         million.

(2) A portion of the net proceeds will be used to repay the amounts outstanding under the revolving credit facility and under the subordinated notes, which were              and             , respectively, as of             , 2014.

(3) The unpaid principal amount of our convertible notes, together with accrued but unpaid interest thereon (which in each case has been accruing since issuance), will be automatically converted into common stock upon the closing of the offering made hereby, at a conversion price equal to 62.5% of the initial public offering price per share of the common stock in this offering.

A $1.00 increase from the assumed initial public offering price of $         per share would decrease the number of shares of common stock issuable upon the conversion of the convertible notes by             shares and $1.00 decrease from the assumed initial public offering price of $         per share would increase the number of shares of common stock issuable upon the conversion of the convertible notes by             shares, in each case, assuming a                     , 2014 closing date of the offering. For each day after the assumed                     , 2014 closing date, the number of shares of common stock issuable upon the convertible notes would increase by             shares, assuming an initial offering price of $         per share. The actual number of shares of common stock to be issued upon the conversion of the convertible notes will be based on the amount of accrued but unpaid interest then outstanding and the actual initial public offering price.

(4) Excludes 80,050,105 shares of our common stock issuable upon the exercise of stock options outstanding as of April 15, 2014 and 112,576 shares of our common stock issuable upon the exercise of warrants to purchase our common stock outstanding as of April 15, 2014.

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DILUTION

If you invest in our common stock, your interest in our net tangible book value will be diluted to the extent of the difference between the initial public offering price and the net tangible book value per share of our common stock immediately after the completion of this offering. Dilution results from the fact that the initial public offering price is substantially in excess of the book value per share attributable to the existing stockholders for the presently outstanding stock.

As of December 31, 2013, our net tangible book value was approximately $(62.2) million, or approximately $(23.71) per share of common stock. Net tangible book value per share represents the amount of our total tangible assets less total liabilities and preferred stock, divided by 2,623,156, the number of shares of our common stock outstanding on December 31, 2013. Our pro forma net tangible book value as of December 31, 2013 was $        , or $         per share of common stock. Pro forma net tangible book value per share represents the amount of our total tangible assets less our total liabilities, divided by the number of shares of our common stock outstanding, as of December 31, 2013, after (a) assuming the exercise for cash of all of our outstanding warrants to purchase Series C preferred stock and (b) giving effect to (i) the automatic conversion of all shares of our preferred stock into 96,333,792 shares of our common stock and (ii) the automatic conversion of all outstanding principal and interest on our convertible notes upon the closing of the offering made hereby into an aggregate of             shares of our common stock, at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014.

After giving effect to the sale by us of shares of our common stock in the offering at the assumed initial public offering price of $        , the mid-point of the price range set forth on the cover page of this prospectus, and after deducting estimated underwriting discounts and estimated offering expenses payable by us, our pro forma as adjusted net tangible book value as of December 31, 2013 would have been approximately $        , or approximately $         per share. This amount represents an immediate increase in pro forma as adjusted net tangible book value of $         per share to our existing stockholders and an immediate dilution in pro forma as adjusted net tangible book value of approximately $         per share to new investors purchasing shares of our common stock in this offering. We determine dilution by subtracting the pro forma as adjusted net tangible book value per share after the offering from the amount of cash that a new investor paid for a share of common stock.

The following table illustrates this dilution on a per share basis:

Assumed initial public offering price per share	$
Pro forma net tangible book value per share as of December 31, 2013
Increase per share attributable to cash payments by new investors in this offering
Pro forma as adjusted net tangible book value per share after this offering
Dilution in pro forma net tangible book value per share to new investors	$

If the underwriters exercise their option to purchase additional shares in full, the pro forma as adjusted net tangible book value per share after giving effect to the offering would be $         per share. This represents an increase in pro forma as adjusted net tangible book value of $         per share to existing stockholders and dilution in pro forma as adjusted net tangible book value of $         per share to new investors.

A $1.00 increase (decrease) in the assumed initial public offering price of $        , the mid-point of the price range set forth on the cover page of this prospectus, would increase (decrease) our pro forma as adjusted net tangible book value after this offering by $         million and the pro forma as adjusted net tangible book value per share after this offering by $         per share and would increase (decrease) the dilution per share to new investors in this offering by $         per share, in each case, assuming the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and assuming the closing of the offering made hereby occurs on                 , 2014. The information discussed above is illustrative only and will adjust based on the actual initial public offering price and other terms of the offering determined at pricing.

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The following table shows, as of                     , 2014, the differences between the number of shares purchased from us, the total consideration paid to us and the average price per share that existing stockholders and new investors paid.

	Shares Purchased			Total Consideration			Average Price per Share
	Number	Percentage		Amount	Percentage
Existing stockholders			%	$		%	$
New investors
Total			%	$		%	$

A $1.00 increase (decrease) in the assumed initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, would increase (decrease) total consideration paid by new investors, total consideration paid by all stockholders and the average price per share paid by all stockholders by $        , $         and $        , respectively, after deducting estimated underwriting discounts and estimated offering expenses payable by us, and assuming the number of shares offered by us, as set forth on the cover page of this prospectus, remains the same and assuming the closing of the offering made hereby occurs on                     , 2014.

The discussion and tables above assume no exercise of the underwriters’ option to purchase additional shares. If the underwriters’ option to purchase additional shares is exercised in full, the number of shares of our common stock held by existing stockholders will be further reduced to     % of the total number of shares of our common stock to be outstanding after the offering, and the number of shares of our common stock held by investors participating in the offering will be further increased to     % of the total number of shares of our common stock to be outstanding after the offering.

In addition, except as noted, the above discussion and table assume no exercise of stock options or warrants to purchase common stock after December 31, 2013. As of December 31, 2013, we had outstanding options to purchase a total of 80,198,540 shares of our common stock at a weighted-average exercise price of $0.11 per share and 112,576 shares of common stock reserved for issuance upon the exercise of outstanding warrants at a weighted-average exercise price of $0.017 per share. If all such options and warrants had been exercised as of December 31, 2013, pro forma as adjusted net tangible book value per share would be $         per share and dilution to new investors would be $         per share. To the extent we grant options to our employees in the future and those options are exercised or other issuances of common stock are made, there will be further dilution to new investors.

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SELECTED CONSOLIDATED FINANCIAL DATA

The following table sets forth our selected consolidated financial data for the periods, and as of the dates, indicated. You should read the following selected consolidated financial data in conjunction with our consolidated financial statements and the related notes thereto included elsewhere in this prospectus and the “Management’s Discussion and Analysis of Financial Condition and Results of Operations” section of this prospectus.

We derived the consolidated statement of operations data for the years ended December 31, 2011, 2012 and 2013, and the consolidated balance sheet data as of December 31, 2012 and 2013, from our audited consolidated financial statements and the related notes thereto included elsewhere in this prospectus. We derived the consolidated statement of operations data for the fiscal years ended December 31, 2009 and 2010, and the consolidated balance sheet data as of December 31, 2009, 2010 and 2011, from our audited consolidated financial statements and the related notes thereto that are not included in this prospectus. Our historical results for prior periods are not necessarily indicative of results to be expected for any future period.

	Year Ended December 31
	2009			2010			2011			2012			2013
	($ in thousands, except share and per share data)
Consolidated statements of operations data:
Revenue:
Product	$	24,752		$	38,690		$	42,717		$	60,389		$	82,057
Research services		3,864			4,519			3,233			3,064			4,037
Total revenue		28,616			43,209			45,950			63,453			86,094
Cost of revenue:
Product		30,462			35,399			47,071			70,025			73,399
Research services		1,788			2,119			1,505			1,396			1,964
Gross profit (loss)		(3,634	)		5,691			(2,626	)		(7,968	)		10,731
Operating expenses:
Research and development		2,524			2,985			4,085			5,142			5,159
Sales and marketing		3,994			4,526			5,565			8,564			9,271
General and administrative		5,430			5,675			8,291			11,299			12,833
Write-off of construction in progress		—			—			—			—			3,440
Total operating expenses		11,948			13,186			17,941			25,005			30,703
Income (loss) from operations		(15,582	)		(7,495	)		(20,567	)		(32,973	)		(19,972	)
Other income (expense):
Interest expense		(3,057	)		(2,415	)		(8,822	)		(21,790	)		(30,599	)
Gain on extinguishment of convertible notes		—			—			—			—			8,898
Loss on exchange of convertible notes		—			—			—			—			(5,697	)
Debt extinguishment costs		—			—			—			(1,379	)		—
Costs associated with postponed public offering		—			—			(3,443	)		—			(241	)
Total other income (expense), net		(3,057	)		(2,415	)		(12,265	)		(23,169	)		(27,639	)
Net income (loss)		(18,639	)		(9,910	)		(32,832	)		(56,142	)		(47,611	)
Accretion (deemed dividends) on preferred stock		(2,984	)		(57,007	)		(23,665	)		47,201			(996	)
Extinguishment of redeemable feature for convertible preferred stock		—			—			—			—			86,161
Earnings attributable to preferred stock shareholders		—			—			—			—			(36,216	)
Net income (loss) attributable to common stockholders	$	(21,623	)	$	(66,917	)	$	(56,497	)	$	(8,941	)	$	1,338

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	Year Ended December 31
	2009			2010			2011			2012			2013
	($ in thousands, except share and per share data)
Per share data:
Net income (loss) attributable to common stockholders per share:
Basic	$	(22.17	)	$	(26.17	)	$	(21.66	)	$	(3.41	)	$	0.51
Diluted	$	(22.17	)	$	(26.17	)	$	(21.66	)	$	(3.41	)	$	0.49
Weighted-average common shares outstanding:
Basic		975,162			2,557,429			2,607,888			2,622,897			2,623,156
Diluted		975,162			2,557,429			2,607,888			2,622,897			2,722,947
Pro forma net income (loss) per share, basic and diluted(1)
Weighted-average common shares outstanding used in computing pro forma net income (loss) per share, basic and diluted(1)

	December 31
	2009		2010			2011			2012			2013
	($ in thousands)
Consolidated balance sheet data:
Cash	$	27,502	$	26,800		$	11,241		$	1,343		$	1,574
Working capital(2)		21,766		24,723			12,532			1,132			(3,460	)
Total assets		64,735		88,795			102,154			95,301			90,442
Total debt		575		8,139			60,462			110,083			138,555
Redeemable preferred stock		31,681		109,786			133,451			86,250			—
Total stockholders’ (deficit) equity		6,153		(58,103	)		(113,513	)		(120,795	)		(61,966	)

(1) Pro forma per share data will be computed based upon the number of shares of common stock outstanding immediately after consummation of this offering applied to our historical net income (loss) amounts and will give retroactive effect to the preferred stock and convertible notes conversions (assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus) and the issuance of the shares of our common stock offered hereby.

(2) Working capital means current assets minus current liabilities.

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The following table presents the calculation of historical and pro forma basic and diluted net income (loss) per share:

	Year Ended December 31
	2009			2010			2011			2012			2013
	($ in thousands, except share and per share data)
Net income (loss) attributable to common stockholders	$	(21,623	)	$	(66,917	)	$	(56,497	)	$	(8,941	)	$	1,338
Deemed dividends (accretion) on preferred stock		2,984			57,007			23,665			(47,201	)		996
Extinguishment of redeemable feature for convertible preferred stock		—			—			—			—			(86,161	)
Earnings attributable to preferred stock shareholders		—			—			—			—			36,216
Interest expense
Discount on conversion of convertible notes
Pro forma net income (loss) attributable to common stockholders
Weighted-average common shares outstanding, basic and diluted
Common shares issued upon conversion of preferred stock
Common shares issued upon conversion of convertible notes and interest thereon
Weighted-average common shares outstanding used in computing pro forma net income (loss) per share, basic and diluted
Pro forma net income (loss) per share, basic and diluted

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MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

You should read the following in conjunction with the “Selected Consolidated Financial Data” and our consolidated financial statements and the related notes thereto included elsewhere in this prospectus. In addition to historical information, the following discussion and analysis includes forward looking information that involves risks, uncertainties and assumptions. Our actual results and the timing of events could differ materially from those anticipated by these forward looking statements as a result of many factors, including those discussed under “Risk Factors” elsewhere in this prospectus. See also “Special Note Regarding Forward Looking Statements” included elsewhere in this prospectus.

Overview

We design, develop and manufacture innovative, high-performance aerogel insulation. We believe our aerogel blankets deliver the best thermal performance of any widely used insulation product available on the market today and provide a combination of performance attributes unmatched by traditional insulation materials. Our end-use customers select our products where thermal performance is critical and to save money, reduce energy use, preserve operating assets and protect workers.

Our insulation is used by oil producers and the owners and operators of refineries, petrochemical plants, LNG facilities, power generating assets and other energy infrastructure. Our Pyrogel and Cryogel product lines were introduced in 2008 and have undergone rigorous technical validation by industry leading end-users and achieved significant market adoption. We also derive product revenue from the building and construction and other end markets. Customers in these markets use our aerogels for applications as diverse as wall systems, military and commercial aircraft, trains, buses, appliances, apparel, footwear and outdoor gear. We estimate that we generated 87% of our 2013 product revenue in the energy infrastructure markets and 13% in the building and construction and other end markets.

We generate product revenue through the sale of our line of aerogel blankets. We market and sell our products primarily through a sales force based in North America, Europe and Asia. In 2013, 68% of our product revenue was generated outside the United States. The efforts of our sales force are supported by a small number of sales consultants with extensive knowledge of a particular market or region. Our sales force is responsible for establishing and maintaining customer and partner relationships, and for delivering highly technical information, and ensuring high quality customer service.

Our salespeople work directly with end-use customers and engineering firms to promote qualification, specification and acceptance of our products. We also rely on an existing and well-established channel of qualified insulation distributors and contractors in more than 30 countries around the world that ensures rapid delivery of our products and strong end-user support. Our salespeople also work to educate insulation contractors about the technical and operating cost advantages of our aerogel blankets.

We also perform research services under contracts with various agencies of the U.S. government, including the Department of Defense and the Department of Energy, and other institutions. Research performed under contract with government agencies and other institutions enables us to develop and leverage technologies into broader commercial applications.

We manufacture our products using our proprietary process and technology at our facility in East Providence, Rhode Island. We have operated the East Providence facility at high volume and high yield since 2008. We commenced operation of a second production line at this facility at the end of March 2011, which doubled our annual nameplate capacity to 40 million to 44 million square feet of aerogel blankets, depending on product mix.

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Our proprietary aerogel technology and manufacturing processes are significant assets. Our intellectual property portfolio is supported by 51 issued patents, with an additional 18 pending in the U.S. and foreign jurisdictions in areas related to product design, chemistry, manufacturing process and application. Our research scientists and process engineers are focused on developing next generation aerogel compositions, form factors and manufacturing technologies. Since inception through December 31, 2013, we have invested $36.7 million into our research and development activities.

Our predecessor company was incorporated in 2001 and spun off from Aspen Systems, Inc., of Marlborough, Massachusetts, to focus on the development and commercialization of aerogel technology. We began selling our first products commercially in the second quarter of 2001. Since inception through December 31, 2013, we have generated $335.2 million in revenue consisting of $290.9 million in product revenue and $44.3 million in research services revenue. As of April 15, 2014, we had 220 employees principally located at two sites in the United States.

Our total revenue has grown from $20.1 million for the year ended December 31, 2008 to $86.1 million for the year ended December 31, 2013. For the year ended December 31, 2012, our total revenue grew 38% to $63.5 million from $46.0 million in 2011. For the year ended December 31, 2013, our total revenue grew 36% to $86.1 million from $63.5 million in 2012.

We have experienced significant losses since inception, have an accumulated deficit of $332.8 million at December 31, 2013, and have ongoing cash flow commitments. We have invested material resources to commercialize aerogel technology and to build a manufacturing infrastructure capable of supplying aerogel products at the volumes and prices required by our customers. We are currently experiencing rapid growth as we strive to serve our expanding customer base.

Factors Affecting Our Performance

Manufacturing Capacity

Our aerogel product revenue increased by 36% in 2013 from 2012 and was in line with our compound annual growth rate of 37% over our last five years. To meet anticipated continued growth in demand for our products, we are engaged in the design, engineering and procurement phase of a third production line in our East Providence facility which we expect to complete in the first half of 2015. We also plan to construct a second manufacturing facility in either Europe or Asia and to commence operations of a first production line at this facility during 2017. We currently estimate that design, development and construction of our third production line in the East Providence facility will require additional expenditures of approximately $30 million. We expect to construct our second manufacturing facility in several phases in order to align manufacturing capacity to anticipated demand for our products. We currently estimate that design, development and construction of an initial production line and plant infrastructure will require expenditures of between $80 million to $100 million. Our ability to successfully bring this capacity online as planned and to ramp-up production in a timely manner will have a significant impact on our financial condition and results of operations.

Revenue Growth

A critical driver to improve our financial performance will be continued revenue growth. We expect that increased revenue will drive incremental improvement in gross profit, operating income and net income, and will lead to higher levels of cash flow from operations. Our ability to achieve and support sufficient revenue to generate net income will require continued near-term investments in manufacturing facilities, capital equipment, technology and personnel, which will negatively impact net income and cash balances in the short-term, but we expect these investments to be drivers of improved financial performance in the long-term. Our revenue growth is in turn dependent on several factors, including adoption rates of our aerogel products, demand for energy infrastructure insulation and our ability to grow our market share.

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Project-Based Revenue

Our product revenue has been and will continue to be generated in large part by demand for insulation associated with large capacity expansions and related capital projects at existing facilities and new-build facility construction. We estimate approximately two-thirds of our product revenue was project-based in 2013. Although we expect to generate a stream of product revenue over time from multiple projects and from numerous customers, the intermittent nature of project-based revenue, including the revenue generated by a single project, could have a material impact on our revenue and results of operations in any given reporting period. In addition, these projects are affected by macroeconomic factors including energy demand and economic growth. Accordingly, our project-based revenue in any given period could also fluctuate due to changes in macroeconomic conditions. Fluctuations in our project-based revenue could, in turn, have a material impact on our results of operations in any given reporting period. See “Risk Factors — Risks Related to Our Business and Strategy — Our revenue may fluctuate, which may result in a high degree of variability in our results of operations and make it difficult for us to plan based on our future outlook and to forecast our future performance.”

Organizational Resources

We plan to expand our resources in support of anticipated growth of our business and to achieve our strategic objectives. We plan to increase our sales force and spending globally to support anticipated growth in demand for our products. We plan to increase engineering resources to manage the anticipated design and construction of a third line in our East Providence facility and a first line in our second manufacturing facility in Europe or Asia. We plan to increase manufacturing staff to support expanded output in our East Providence facility during 2015 and in multi-facility operations in 2017. We intend to increase personnel, funding and capital equipment devoted to the research and development of new and advanced technologies. We also plan to expand general and administrative staff in support of our operating as a public company. These plans will require a significant investment in managerial talent, human resources, information systems, processes and controls to ensure maintenance of efficient and economic operations. These investments are critical to our ability to increase revenue, to generate net income and to fully fund operations.

Components of Our Results of Operations

Revenue

We recognize product revenue from the sale of our line of aerogel products and research services revenue from the provision of services under contracts with various agencies of the U.S. government and other institutions. Product revenue is recognized upon transfer of title and risk of loss, which is generally upon shipment or delivery. The following table sets forth the total revenue for the periods presented:

	Year Ended December 31
	2011		2012		2013
	($ in thousands)
Revenue:
Product	$	42,717	$	60,389	$	82,057
Research services		3,233		3,064		4,037
Total revenue	$	45,950	$	63,453	$	86,094

Product revenue accounted for 93%, 95% and 95% of total revenue for the years ended December 31, 2011, 2012 and 2013, respectively. We expect continued growth in product revenue due to increasing market adoption of our line of aerogel blankets supported by increasing demand projected within all segments of the energy infrastructure market. We expect that research services revenue will continue to decline as a percentage of total revenue.

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A substantial majority of our revenue is generated from a limited number of direct customers, principally distributors, contractors and OEMs. Our 10 largest customers accounted for approximately 65% of our total revenue during the year ended December 31, 2013, and we expect that most of our revenue will continue to come from a relatively small number of customers for the foreseeable future. In 2011, Enershield Industries Ltd. and Aerogel Korea Co., Ltd. represented 13% and 10% of total revenue, respectively; in 2012, Distribution International represented 13% of total revenue; and in 2013, Distribution International and Alltech Consulting Co. Ltd. represented 15% and 11% of total revenue, respectively. For each of the periods discussed above, there were no other customers that represented 10% or more of our total revenues.

We conduct business across the globe, with a substantial portion of our sales outside the United States for each of the years ended December 31, 2011, 2012 and 2013. In addition, we may expand our operations outside of the United States. Total revenue from outside of the United States, based on shipment destination or research services location, amounted to $30.8 million or 67% of our total revenue, $43.5 million or 69% of our total revenue, and $55.9 million, or 65% of our total revenue, in the years ended December 31, 2011, 2012 and 2013, respectively.

Cost of Revenue

Cost of revenue for our product revenue consists primarily of materials and manufacturing expense, including direct labor and manufacturing overhead, including depreciation. Cost of product revenue is recorded when the related product revenue is recognized. Cost of product revenue also includes stock-based compensation of manufacturing employees and costs of shipping.

Material is our most significant component of cost of product revenue and includes fibrous batting, silica materials and additives. Material costs as a percentage of product revenue were 53%, 61% and 47% for the years ended December 31, 2011, 2012 and 2013, respectively. Material costs as a percentage of product revenue vary from product to product due to differences in average selling prices, material requirements, blanket thickness and manufacturing yields. As a result, material costs as a percentage of revenue will vary from period to period due to changes in the mix of aerogel products sold. However, in general, we expect material costs in the aggregate to decline as a percentage of revenue as we seek to achieve higher selling prices, material sourcing improvements, new material sources and manufacturing yield enhancements for our aerogel products.

Manufacturing expense is also a significant component of cost of revenue. Manufacturing expense as a percentage of product revenue was 58%, 56% and 42% for the years ended December 31, 2011, 2012 and 2013, respectively. We incurred a significant increase in manufacturing expense associated with the operation of our second production line in the East Providence facility beginning in 2011. These costs were principally fixed in nature and constituted an increased percentage of product revenue during 2011 and 2012 as we increased production toward nameplate capacity. During 2013, manufacturing expense decreased as a percentage of product revenue as a result of strong revenue growth supported by the expanded manufacturing capacity and improved manufacturing productivity. As we continue to increase manufacturing capacity in our East Providence facility and a second plant, we expect manufacturing expense as a percentage of product revenue will increase in the near-term following each expansion but will decrease in the long-term with increased revenues supported by the effect of completed capacity expansions.

Cost of revenue for our research services revenue consists primarily of direct labor costs of research personnel committed to funded research and development contracts, as well as third-party consulting, and associated direct material costs. This cost of revenue also includes overhead expenses associated with project resources, engineering tools and supplies. Cost of revenue for our research services revenue is recorded when the related research services revenue is recognized.

Gross Profit

Our gross profit as a percentage of revenue is affected by a number of factors, including the mix between product revenue and research services revenue, the mix of aerogel products sold, average selling prices, average

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material costs, our actual manufacturing costs and the costs associated with expansions and start-up of production capacity. As we continue to build out our manufacturing capacity, we expect increased manufacturing expenses will periodically have a negative impact on gross profit, but will set the framework for improved gross profit moving forward. Accordingly, we expect our gross profit in absolute dollars and as a percentage of revenue to vary from period to period as we expand our manufacturing capacity. However, in general, following the completion of our capacity expansions, we expect gross profit to improve as a percentage of revenue in the long-term due to increases in manufacturing productivity, increased production volumes, improved manufacturing yields and material purchasing efficiencies.

Operating Expenses

Operating expenses consist of research and development, sales and marketing, and general and administrative expenses. The largest component of our operating expenses is personnel costs, consisting of salaries, benefits, incentive compensation and stock-based compensation. We expect to continue to hire a significant number of new employees in order to support our anticipated growth. In any particular period, the timing of additional hires could materially affect our operating expenses, both in absolute dollars and as a percentage of revenue.

Research and Development Expenses

Research and development expenses consist primarily of expenses for personnel engaged in the development of next generation aerogel compositions, form factors and manufacturing technologies. These expenses also include testing services, prototype expenses, consulting services, equipment depreciation, facilities costs and related overhead. We expense research and development costs as incurred. We expect to continue to devote substantial resources to the development of new aerogel technology. We believe that these investments are necessary to maintain and improve our competitive position. We expect that our research and development expenses will continue to increase as we continue to invest in additional research and engineering personnel and the infrastructure required in support of their efforts. Accordingly, we expect that our research and development expenses will continue to increase in absolute dollars but decrease as a percentage of revenue in the long-term.

Sales and Marketing Expenses

Sales and marketing expenses consist primarily of personnel costs, incentive compensation, marketing programs, travel and related costs, consulting expenses and facilities-related costs. We plan to expand our sales force and sales consultants globally to drive anticipated growth in customers and demand for our products. We expect that sales and marketing expenses will continue to increase in absolute dollars but decrease as a percentage of revenue in the long-term.

General and Administrative Expenses

General and administrative expenses consist primarily of personnel costs, legal expenses, consulting and professional services, tax and audit costs, and expenses for our executive, finance, human resources and information technology organizations. We expect general and administrative expenses to increase as we incur additional costs related to operating as a publicly-traded company, including costs of compliance with securities, corporate governance and related regulations, investor relations expenses, increased insurance premiums, including director and officer insurance, and increased audit and legal fees. In addition, we expect to add general and administrative personnel to support the anticipated growth of our business and continued expansion of our manufacturing operations. We expect that general and administrative expenses will continue to increase in absolute dollars but decrease as a percentage of revenue in the long-term.

Other Income (Expense)

Other income (expense) consists of (i) interest expense consisting primarily of fair market value adjustments to our subordinated notes, convertible notes and the issuance of our Series C warrants, subordinated and convertible

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note issuance costs, the amortization of the subordinated note debt discount, and imputed interest on our obligations under our cross license agreement with Cabot Corporation, (ii) gains or losses on extinguishment or exchange of subordinated notes and convertible notes and (iii) costs associated with a postponed public offering.

Provision for Income Taxes

We have incurred net losses since inception and have not recorded benefit provisions for U.S. federal income taxes or state income taxes since the tax benefits of our net losses have been offset by valuation allowances due to the uncertainty associated with the utilization of net operating loss carryforwards.

Key Metrics and Non-GAAP Financial Measures

We regularly review a number of metrics, including the following key metrics, to evaluate our business, measure our performance, identify trends affecting our business, formulate financial projections and make strategic decisions.

Square Foot Operating Metric

We price our product and measure our product shipments in square feet. We have produced in excess of 100 million square feet of aerogel blankets in the East Providence facility since 2008. Our annual production capacity is currently 40 million to 44 million square feet of aerogel blankets, depending on product mix. We believe the square foot operating metric allows us and our investors to measure the growth in our manufacturing capacity and product shipments on a uniform and consistent basis. The following chart sets forth product shipments associated with recognized revenue in square feet for the periods presented:

	Year Ended December 31
	2011		2012		2013
	(Square feet in thousands)
Product shipments in square feet		19,473		27,280		35,560

Adjusted EBITDA

We use Adjusted EBITDA, a non-GAAP financial measure, as a means to assess our operating performance. We define Adjusted EBITDA as net income (loss) before interest expense, taxes, depreciation, amortization, stock-based compensation expense and other items, from time to time that we do not believe are indicative of our core operating performance, which recently have included loss on disposal of assets, gain or loss on extinguishment or exchange of debt, write-off of costs of postponed financing activities and write-off of construction in progress. Adjusted EBITDA is a supplemental measure of our performance that is not presented in accordance with GAAP. Adjusted EBITDA should not be considered as an alternative to net income (loss) or any other measure of financial performance calculated and presented in accordance with GAAP. In addition, our definition and presentation of Adjusted EBITDA may not be comparable to similarly titled measures presented by other companies.

We use Adjusted EBITDA:

• as a measure of operating performance because it does not include the impact of items that we do not consider indicative of our core operating performance;

• for planning purposes, including the preparation of our annual operating budget, to allocate resources to enhance the financial performance of our business; and

• as a performance measure used under our bonus plan.

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We also believe that the presentation of Adjusted EBITDA provides useful information to investors with respect to our results of operations and in assessing the performance and value of our business. Various measures of EBITDA are widely used by investors to measure a company’s operating performance without regard to items that can vary substantially from company to company depending upon financing and accounting methods, book values of assets, capital structures and the methods by which assets were acquired. See footnote (3) under “Prospectus Summary –Summary Consolidated Financial Data” for a discussion of the limitations of Adjusted EBITDA.

To properly and prudently evaluate our business, we encourage you to review the GAAP financial statements included elsewhere in this prospectus, and not to rely on any single financial measure to evaluate our business.

The following table presents a reconciliation of net income (loss), the most directly comparable GAAP measure, to Adjusted EBITDA for the years presented:

	Year Ended December 31
	2011			2012			2013
	($ in thousands)
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)
Interest expense		8,822			21,790			30,599
Depreciation and amortization		7,521			9,684			10,061
Loss on disposal of assets		—			2,489			230
Stock-based compensation(1)		1,064			1,654			4,426
Gain on extinguishment of convertible notes		—			—			(8,898	)
Loss on exchange of convertible notes		—			—			5,697
Debt extinguishment costs		—			1,379			—
Write-off of costs associated with postponed public offering		3,443			—			241
Write-off of construction in progress		—			—			3,440
Adjusted EBITDA	$	(11,982	)	$	(19,146	)	$	(1,815	)

(1) Represents non-cash stock-based compensation related to vesting and modifications of stock option grants.

The following table presents a reconciliation of net income (loss), the most directly comparable GAAP measure, to Adjusted EBITDA for the quarters presented:

	Three Months Ended
	2012												2013
	March 31			June 30			Sept. 30			Dec. 31			March 31			June 30			Sept. 30			Dec. 31
	($ in thousands)
Net income (loss)	$	(9,645	)	$	(12,279	)	$	(10,218	)	$	(24,000	)	$	1,027		$	(18,984	)	$	(12,704	)	$	(16,950	)
Interest expense(1)		2,110			3,447			1,513			14,720			(3,366	)		15,620			8,039			10,306
Depreciation and amortization		2,142			2,346			2,564			2,632			2,469			2,479			2,483			2,630
Loss on disposal of assets		—			—			—			2,489			—			—			—			230
Stock-based compensation(2)		299			431			438			486			495			510			2,916			505
Gain on extinguishment of convertible notes		—			—			—			—			(8,898	)		—			—			—
Loss on exchange of convertible notes		—			—			—			—			5,212			485			—			—
Debt extinguishment costs		—			—			1,379			—			—			—			—			—
Costs associated with postponed public offering		—			—			—			—			—			241			—			—
Write-off of construction in progress		—			—			—			—			—			—			—			3,440
Adjusted EBITDA	$	(5,094	)	$	(6,055	)	$	(4,324	)	$	(3,673	)	$	(3,061	)	$	351		$	734		$	161

(1) Interest expense consists primarily of fair market value adjustments related to our subordinated notes, convertible notes and the issuance of our Series C warrants, subordinated note and convertible note issuance

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costs, the amortization of the subordinated note debt discount and imputed interest on our obligations under our cross license agreements with Cabot Corporation.

(2) Represents non-cash stock-based compensation related to vesting and modifications of stock option grants.

Our Adjusted EBITDA is affected by a number of factors including the mix between product revenue and research services revenue, the mix of aerogel products sold, average selling prices, average material costs, our actual manufacturing costs, the costs associated with expansions and start-up of additional production capacity, and the amount and timing of operating expenses. As we continue to grow our base of product revenue and to build out manufacturing capacity, we expect increased manufacturing expenses will periodically have a negative impact on Adjusted EBITDA, but will set the framework for improved Adjusted EBITDA moving forward. Accordingly, we expect that our Adjusted EBITDA will vary from period to period as we expand our manufacturing capacity.

Emerging Growth Company Status

The JOBS Act permits an “emerging growth company” such as us to take advantage of an extended transition period to comply with new or revised accounting standards applicable to public companies. We are choosing to opt out of this provision and, as a result, we will comply with new or revised accounting standards as required when they are adopted. This decision to opt out of the extended transition period under the JOBS Act is irrevocable.

Results of Operations

The following tables set forth our results of operations for the periods presented:

	Year Ended December 31
	2011			2012			2013
	($ in thousands)
Revenue:
Product	$	42,717		$	60,389		$	82,057
Research services		3,233			3,064			4,037
Total revenue		45,950			63,453			86,094
Cost of revenue:
Product		47,071			70,025			73,399
Research services		1,505			1,396			1,964
Gross profit (loss)		(2,626	)		(7,968	)		10,731
Operating Expenses:
Research and development		4,085			5,142			5,159
Sales and marketing		5,565			8,564			9,271
General and administrative		8,291			11,299			12,833
Write-off of construction in progress		—			—			3,440
Total operating expenses		17,941			25,005			30,703
Income (loss) from operations		(20,567	)		(32,973	)		(19,972	)
Other income (expense):
Interest expense		(8,822	)		(21,790	)		(30,599	)
Gain on extinguishment of convertible notes		—			—			8,898
Loss on exchange of convertible notes		—			—			(5,697	)
Debt extinguishment costs		—			(1,379	)		—
Costs associated with postponed public offering		(3,443	)		—			(241	)
Total other income (expense), net		(12,265	)		(23,169	)		(27,639	)
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)

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Year ended December 31, 2012 compared to year ended December 31, 2013

The following tables set forth our results of operations for the periods presented:

	Year Ended December 31												Year Ended December 31
	2012			2013			$ Change			% Change			2012			2013
	($ in thousands)												(Percentage of total revenue)
Revenue:
Product	$	60,389		$	82,057		$	21,668			36	%		95	%		95	%
Research services		3,064			4,037			973			32	%		5	%		5	%
Total revenue		63,453			86,094			22,641			36	%		100	%		100	%
Cost of revenue:
Product		70,025			73,399			3,374			5	%		110	%		85	%
Research services		1,396			1,964			568			41	%		2	%		2	%
Gross profit (loss)		(7,968	)		10,731			18,699			235	%		(13	)%		12	%
Operating expenses:
Research and development		5,142			5,159			17			0	%		8	%		6	%
Sales and marketing		8,564			9,271			707			8	%		13	%		11	%
General and administrative		11,299			12,833			1,534			14	%		18	%		15	%
Write-off of construction in progress		—			3,440			3,440			100	%		—	%		4	%
Total operating expenses		25,005			30,703			5,698			23	%		39	%		36	%
Income (loss) from operations		(32,973	)		(19,972	)		13,001			39	%		(52	)%		(23	)%
Other income (expense):
Interest expense		(21,790	)		(30,599	)		(8,809	)		(40	)%		(34	)%		(36	)%
Gain on extinguishment of convertible notes		—			8,898			8,898			100	%		—	%		10	%
Loss on exchange of convertible notes		—			(5,697	)		(5,697	)		(100	)%		—	%		(7	)%
Debt extinguishment costs		(1,379	)		—			1,379			100	%		(2	)%		—	%
Costs associated with postponed public offering		—			(241	)		(241	)		(100	)%		—	%		—	%
Total other income (expense), net		(23,169	)		(27,639	)		(4,470	)		(19	)%		(37	)%		(32	)%
Net income (loss)	$	(56,142	)	$	(47,611	)	$	8,531			15	%		(88	)%		(55	)%

Revenue

	Year Ended December 31										Change
	2012					2013
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
Revenue:
Product	$	60,389		95	%	$	82,057		95	%	$	21,668		36	%
Research services		3,064		5	%		4,037		5	%		973		32	%
Total revenue	$	63,453		100	%	$	86,094		100	%	$	22,641		36	%

The following chart sets forth product shipments in square feet for the periods presented:

	Year Ended December 31				Change
	2012		2013		Amount		Percentage
Product shipments in square feet (in thousands)		27,280		35,560		8,280		30	%

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Total revenue increased $22.6 million, or 36%, in 2013 to $86.1 million from $63.5 million in 2012 primarily as a result of an increase in product revenue.

Product revenue increased $21.7 million, or 36%, to $82.1 million in 2013 from $60.4 million in 2012. This increase was principally the result of an increase in sales of our aerogel products in the refinery and petrochemical sectors in Asia, North America and South America during 2013. This increase in demand during 2013 included increased sales of $4.9 million to one distributor in Asia primarily related to construction of a new petrochemical plant in Taiwan, increased sales of $4.6 million to another distributor in the United States for general distribution into the energy infrastructure market, and increased sales of $4.6 million to a South American distributor primarily related to construction of expanded capacity in a petrochemical plant in Brazil. In volume terms, product shipments increased 8.3 million square feet, or 30%, to 35.6 million square feet of aerogel products, as compared to 27.3 million square feet in 2012. We also increased the prices of some of our products during 2013. We did not increase the prices of our products during 2012.

Research services revenue increased $1.0 million, or 32%, to $4.0 million in 2013 from $3.1 million in 2012 primarily due to revenue generated in 2013 under a significant contract with the Department of Energy.

Product revenue as a percentage of total revenue was 95% of total revenue in 2013 and 2012. Research services revenue was 5% of total revenue in 2013 and 2012. We expect that product revenue will increase as a percentage of our total revenue due to the anticipated growth in demand for our products in the energy infrastructure market.

Cost of Revenue

	Year Ended December 31																Change
	2012								2013
	Amount		Percentage of  Related Revenue			Percentage of  Total Revenue			Amount		Percentage of  Related of Revenue			Percentage of  Total Revenue
																	Amount		Percentage
	($ in thousands)
Cost of revenue:
Product	$	70,025		116	%		110	%	$	73,399		89	%		85	%	$	3,374		5	%
Research services		1,396		46	%		2	%		1,964		49	%		2	%		568		41	%
Total cost of revenue	$	71,421		113	%		113	%	$	75,363		88	%		88	%	$	3,942		6	%

Total cost of revenue increased $3.9 million, or 6%, to $75.3 million in 2013 from $71.4 million in 2012. The increase in total cost of revenue was the result of an increase of $2.0 million in material costs and an increase of $1.3 million in manufacturing expense to support increased product revenue and an increase of $0.6 million in cost of research services to support increased research services revenue.

Product cost of revenue increased $3.4 million, or 5%, to $73.4 million in 2013 from $70.0 million in 2012. Product cost of revenue as a percentage of product revenue decreased to 89% during 2013 from 116% in 2012 as a result of a reduction in both material costs and manufacturing expense as a percentage of product revenue during the year. The reduction in material costs as a percentage of product revenue was the result of improved manufacturing yields and purchasing efficiency. The reduction in manufacturing expense as a percentage of product revenue was the result of improved manufacturing throughput and efficiency.

We expect that material costs and manufacturing expense will continue to increase during 2014 due to the increase in production volume in our East Providence facility required to support expected revenue growth. In addition, we expect an increase in manufacturing expense associated with initial start-up costs leading to operation of a third line in the East Providence facility. However, we expect the cost of product revenue as a

59

percentage of product revenue for our 2014 fiscal year to decrease as a result of expected revenue growth and productivity improvements during the year.

Research services cost of revenue increased $0.6 million, or 41%, to $2.0 million in 2013 from $1.4 million in 2012. The increase was due in large part to the 32% growth in research service revenue during 2013 in combination with an increase in cost of research services revenue as a percentage of research services revenue to 49% in 2013 from 46% in 2012. The increase in cost of research services revenue was due to an unfavorable mix of labor and expense required to perform the contracted research, each of which carries a different rate of reimbursement.

Gross Profit (Loss)

	Year Ended December 31											Change
	2012						2013
	Amount			Percentage of  Revenue			Amount		Percentage of  Revenue
												Amount		Percentage
	($ in thousands)
Gross profit (loss)	$	(7,968	)		(13	)%	$	10,731		12	%	$	18,699		235	%

Gross profit increased $18.7 million to $10.7 million in 2013 from a gross loss of $8.0 million in 2012. This increase in gross profit was principally the result of a reduction in material costs and manufacturing expenses as a percentage of product revenue due to improved manufacturing yields, purchasing efficiency and productivity at our East Providence facility. In addition, the increase in the price of some of our products during 2013 also contributed to the increase in gross profit. Gross profit as a percentage of total revenue increased to 12% of total revenue in 2013 from a gross loss of 13% of total revenue in 2012. We expect gross profit as a percentage of total revenue to increase during 2014 due to growth in product revenue and continued improvements in manufacturing throughput and efficiency.

Research and Development Expenses

	Year Ended December 31										Change
	2012					2013
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
Research and development expenses	$	5,142		8	%	$	5,159		6	%	$	17		0	%

R&D expenses increased $0.1 million to $5.2 million in 2013 from $5.1 million in 2012. This increase was principally the result of an increase of $0.6 million in payroll and related costs for engineering personnel partially offset by a decrease of $0.3 million in material expense and $0.2 million in contract engineering expense. R&D costs as a percentage of total revenue decreased to 6% during 2013 from 8% during 2012. This decrease was the result of growth in total revenue during 2013. We expect that our research and development expenses will increase as we invest in additional research and engineering personnel and the infrastructure required in support of their efforts. However, we expect that research and development expenses will decline as a percentage of total revenue due to projected growth in product revenue.

Sales and Marketing Expenses

	Year Ended December 31										Change
	2012					2013
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
Sales and marketing expenses	$	8,564		13	%	$	9,271		11	%	$	707		8	%

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Sales and marketing expenses increased $0.7 million, or 8%, to $9.3 million in 2013 from $8.6 million during 2012. The $0.7 million increase was primarily the result of the growth of $1.0 million in payroll and related costs associated with an increase in sales personnel and incentive compensation, partially offset by a $0.1 million decrease in other selling expense and a $0.2 million decrease in travel expense. Sales and marketing expenses as a percentage of total revenue decreased to 11% during 2013 from 13% in 2012. This decrease was the result of the growth in total revenue during 2013. We plan to continue to expand our sales force and sales consultants globally during 2014 to support anticipated growth in customers and demand for our products. We expect that sales and marketing expenses will increase in absolute dollars but decrease as a percentage of total revenue in the long-term due to projected growth in product revenue.

General and Administrative Expenses

	Year Ended December 31										Change
	2012					2013
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
General and administrative expenses	$	11,299		18	%	$	12,833		15	%	$	1,534		14	%

G&A expenses increased $1.5 million, or 14%, to $12.8 million in 2013 from $11.3 million in 2012. This increase was primarily the result of a $3.0 million increase in payroll and related costs of executive, finance and human resource personnel partially offset by a $1.4 million decrease in legal and professional fees, and a $0.1 million decrease in all other expense. G&A expenses as a percentage of total revenue decreased to 15% for 2013 from 18% in 2012. This decrease was principally driven by the strong increase in total revenue in 2013. We expect G&A expenses to increase as we incur additional costs related to operating as a publicly traded company, including costs of compliance with securities, corporate governance and related regulations, investor relations expenses, increased insurance premiums, including director and officer insurance, and increased legal and audit fees. In addition, we expect to add general and administrative personnel to support the anticipated growth of our business and continued expansion of our manufacturing operations. As a result, we expect that G&A expenses will increase in absolute dollars but will decline as a percentage of total revenue in the long-term as a result of projected growth in product revenue.

Write-off of construction in progress

During 2013, we redesigned and reduced the planned scale of the third production line. As a result, we reviewed the construction in progress assets associated with the third production line and determined that $3.0 million had no future use. In addition, we concluded that an additional $0.4 million of construction in progress assets were not utilized or functional. Accordingly, we recorded a $3.4 million impairment charge during 2013 related to the write-off of construction in progress assets. We did not record any write-offs of construction in progress in 2012.

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Other Income (Expense)

	Year Ended December 31												Change
	2012						2013
	Amount			Percentage of  Revenue			Amount			Percentage of  Revenue
													Amount			Percentage
	($ in thousands)
Other income (expense):
Interest expense	$	(21,790	)		(34	)%	$	(30,599	)		(36	)%	$	(8,809	)		(40	)%
Gain on extinguishment of convertible notes		—			—	%		8,898			10	%		8,898			100	%
Loss on exchange of convertible notes		—			—	%		(5,697	)		(7	)%		(5,697	)		(100	)%
Debt extinguishment costs		(1,379	)		(2	)%		—			—	%		1,379			100	%
Costs associated with postponed public offering		—			—	%		(241	)		—	%		(241	)		(100	)%
Total other income (expense), net	$	(23,169	)		(37	)%	$	(27,639	)		(32	)%	$	(4,470	)		(19	)%

Total other income (expense), net increased $4.5 million, or 19%, to $27.6 million in 2013 from $23.2 million in 2012. This increase was primarily the result of an increase in interest expense of $8.8 million, a $5.7 million loss on exchange of convertible notes related to an exchange of convertible notes for senior convertible notes, and costs associated with a postponed public offering of $0.2 million, partially offset by an $8.9 million gain on the extinguishment of convertible notes related to an amendment to the terms of the notes and a decrease of $1.4 million in debt extinguishment costs. The increase in interest expense was primarily due to the recognition of the fair value upon issuance of the Series C warrants, which was treated as an issuance cost in the March 2013 financing.

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Year ended December 31, 2011 compared to year ended December 31, 2012

The following tables set forth our results of operations for the periods presented:

	Year Ended December 31												Year Ended December 31
	2011			2012			$ Change			% Change			2011			2012
	($ in thousands)												(Percentage of total revenue)
Revenue:
Product	$	42,717		$	60,389		$	17,672			41	%		93	%		95	%
Research services		3,233			3,064			(169	)		(5	)%		7	%		5	%
Total revenue		45,950			63,453			17,503			38	%		100	%		100	%
Cost of revenue:
Product		47,071			70,025			22,954			49	%		102	%		110	%
Research services		1,505			1,396			(109	)		(7	)%		3	%		2	%
Gross profit (loss)		(2,626	)		(7,968	)		(5,342	)		(203	)%		(6	)%		(13	)%
Operating expenses:
Research and development		4,085			5,142			1,057			26	%		9	%		8	%
Sales and marketing		5,565			8,564			2,999			54	%		12	%		13	%
General and administrative		8,291			11,299			3,008			36	%		18	%		18	%
Total operating expenses		17,941			25,005			7,064			39	%		39	%		39	%
Income (loss) from operations		(20,567	)		(32,973	)		(12,406	)		(60	)%		(45	)%		(52	)%
Other income (expense):
Interest expense		(8,822	)		(21,790	)		(12,968	)		(147	)%		(19	)%		(34	)%
Debt extinguishment costs		—			(1,379	)		(1,379	)		(100	)%		—	%		(2	)%
Costs associated with postponed public offering		(3,443	)		—			3,443			100	%		(7	)%		—	%
Total other income (expense), net		(12,265	)		(23,169	)		(10,904	)		(89	)%		(27	)%		(37	)%
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(23,310	)		(71	)%		(71	)%		(88	)%

Revenue

	Year Ended December 31										Change
	2011					2012
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount			Percentage
	($ in thousands)
Revenue:
Product	$	42,717		93	%	$	60,389		95	%	$	17,672			41	%
Research services		3,233		7	%		3,064		5	%		(169	)		(5	)%
Total revenue	$	45,950		100	%	$	63,453		100	%	$	17,503			38	%

The following chart sets forth product shipments in square feet for the periods presented:

	Year Ended December 31				Change
	2011		2012		Amount		Percentage
Product shipments in square feet (in thousands)		19,473		27,280		7,807		40	%

Total revenue increased $17.5 million, or 38%, in 2012 to $63.5 million from $46.0 million in 2011, primarily as a result of an increase in product revenue. Product revenue increased $17.7 million, or 41%, to $60.4 million in 2012 from $42.7 million in 2011. This increase was principally the result of an increase in demand for

63

our aerogel products in the energy infrastructure market in Asia and the United States during 2012. This increase in demand during 2012 included increased sales of $3.6 million to one distributor in Asia primarily related to construction of a new petrochemical plant in Taiwan, increased sales of $2.9 million to a Canadian distributor primarily related to capital projects in the oil-sands, and increased sales of $2.6 million to an end-user for a solar power project located in the United States. In volume terms, product shipments increased 7.8 million square feet, or 40%, to 27.3 million square feet of aerogel products, as compared to 19.5 million square feet in 2011. We did not increase the prices of our products during the periods presented.

Product revenue as a percentage of total revenue grew to 95% in 2012 from 93% in 2011 due to growth in product revenue. Research services revenue declined to 5% of total revenue in 2012 from 7% in 2011.

Cost of Revenue

	Year Ended December 31
	2011								2012
			Percentage of  Related Revenue			Percentage of  Total Revenue					Percentage of  Related of Revenue			Percentage of  Total Revenue
																	Change
	Amount								Amount								Amount			Percentage
	($ in thousands)
Cost of revenue:
Product	$	47,071		110	%		102	%	$	70,025		116	%		110	%	$	22,954			49	%
Research services		1,505		47	%		3	%		1,396		46	%		2	%		(109	)		(7	)%
Total cost of revenue	$	48,576		106	%		106	%	$	71,421		113	%		113	%	$	22,845			47	%

Total cost of revenue increased $22.8 million, or 47%, to $71.4 million in 2012 from $48.6 million in 2011. The increase in total cost of revenue was the result of an increase of $14.1 million in material costs to support increased product revenue and unfavorable manufacturing yields associated with operation of our second production line in the East Providence facility, which became operational during the second quarter of 2011, and an increase of $8.9 million in manufacturing expenses associated with operation of our second line for a full year and to support increased product revenue, offset slightly by a decrease of $0.1 million in cost of research services associated with the decline in research services revenue.

Product cost of revenue increased $23.0 million, or 49%, to $70.0 million in 2012 from $47.1 million in 2011. Product cost of revenue as a percentage of product revenue increased to 116% during 2012 from 110% in 2011. The increase in product cost of revenue as a percentage of product revenue was driven by the increase in manufacturing expense and unfavorable manufacturing yields as we increased output from the second production line in the East Providence facility toward nameplate capacity during 2012.

Research services cost of revenue decreased $0.1 million, or 7%, to $1.4 million during 2012 from $1.5 million during 2011. The decrease was due to the decline in research services provided during 2012. Research services cost of revenue as a percentage of research services revenue decreased to 46% during 2012 from 47% in 2011 principally due to the mix of labor and expense required to perform the contracted research, each of which carries a different rate of reimbursement.

Gross Profit (Loss)

	Year Ended December 31												Change
	2011						2012
	Amount			Percentage of  Revenue			Amount			Percentage of  Revenue
													Amount			Percentage
	($ in thousands)
Gross profit (loss)	$	(2,626	)		(6	)%	$	(7,968	)		(13	)%	$	(5,342	)		(203	)%

64

Gross loss increased $5.3 million, or 203%, to $8.0 million in 2012 from $2.6 million in 2011. This increase in gross loss was driven by increased manufacturing expenses and unfavorable manufacturing yields as we increased output from the second production line in the East Providence facility toward nameplate capacity during 2012. Gross loss as a percentage of total revenue increased to 13% of total revenue in 2012 from 6% of total revenue in 2011.

Research and Development Expenses

	Year Ended December 31										Change
	2011					2012
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
Research and development expenses	$	4,085		9	%	$	5,142		8	%	$	1,057		26	%

R&D expenses increased $1.1 million, or 26%, to $5.1 million in 2012 from $4.1 million in 2011. This increase was principally the result of an increase of $0.7 million in payroll and related costs for research personnel and an increase of $0.3 million in material expense. R&D costs as a percentage of total revenue decreased from 9% during 2011 to 8% during 2012. This decrease was the result of the growth in total revenue in 2012.

Sales and Marketing Expenses

	Year Ended December 31										Change
	2011					2012
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
Sales and marketing expenses	$	5,565		12	%	$	8,564		13	%	$	2,999		54	%

Sales and marketing expenses increased $3.0 million, or 54%, to $8.6 million during 2012 from $5.6 million during 2011. This increase was primarily the result of a $2.4 million increase in payroll and related costs associated with an increase in sales personnel to support product revenue growth, a $0.1 million increase in professional fees, a $0.3 million increase in travel expense and a $0.2 million increase in other expense. Sales and marketing expenses as a percentage of total revenue increased to 13% during 2012 from 12% in 2011. This increase was due to planned investments in sales resources and expenses to support revenue growth.

General and Administrative Expenses

	Year Ended December 31										Change
	2011					2012
	Amount		Percentage of  Revenue			Amount		Percentage of  Revenue
											Amount		Percentage
	($ in thousands)
General and administrative expenses	$	8,291		18	%	$	11,299		18	%	$	3,008		36	%

G&A expenses increased $3.0 million, or 36%, to $11.3 million in 2012 from $8.3 million in 2011. This increase was primarily the result of a $1.0 million increase in payroll and related costs of executive, finance and human resource personnel, a $0.9 million increase in legal and professional fees, a $0.5 million increase in depreciation, a $0.3 million increase in information technology expense, a $0.1 million increase in facilities expense, and a $0.2 million increase in all other expenses. G&A expenses as a percentage of total revenue remained constant at 18% for 2012 and 2011.

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Other Income (Expense)

	Year Ended December 31												Change
	2011						2012
	Amount			Percentage of  Revenue			Amount			Percentage of  Revenue
													Amount			Percentage
	($ in thousands)
Other income (expense):
Interest expense	$	(8,822	)		(19	)%	$	(21,790	)		(34	)%	$	(12,968	)		(147	)%
Debt extinguishment costs		—			0	%		(1,379	)		(2	)%		(1,379	)		(100	)%
Write-off of costs associated with postponed public offering		(3,443	)		(7	)%		—			—	%		3,443			100	%
Total other income (expense), net	$	(12,265	)		(27	)%	$	(23,169	)		(37	)%	$	(10,904	)		(89	)%

Total other income (expense), net increased $10.9 million, or 89%, to $23.2 million in 2012 from $12.3 million in 2011. This increase was primarily the result of an increase of $13.0 million in interest expense related to an increase in convertible notes and subordinated notes, and an increase in debt extinguishment costs of $1.4 million related to a change in the fair value of the subordinated notes due to an amendment, partially offset by a decrease in costs associated with a postponed public offering, which totaled $3.4 million in 2011.

Quarterly Results of Operations

The unaudited consolidated financial statements for each of the quarters presented below were prepared on a basis consistent with our audited consolidated financial statements and include all adjustments, consisting of normal and recurring adjustments, that our management considers necessary for a fair presentation of the results of operations for such periods. You should review our quarterly operating results in conjunction with our consolidated financial statements and the related notes located elsewhere in this prospectus. The results of operations for any quarter are not necessarily indicative of the results of operations for any future periods.

Quarterly Results

Our operating results may fluctuate for a variety of reasons outside of our control, including the intermittent nature of our project-based product revenue, macroeconomic factors and seasonal factors that influence our customers and our markets.

Our product revenue is generated in part by demand for insulation associated with new-build construction of facilities, capital expansions and related capital projects, and larger maintenance-related projects. The revenue generated by a single project could be material to our revenue and results of operations in any given reporting period. In addition, we believe that these projects are affected by macroeconomic factors including the price of oil and economic growth. Accordingly, our project-based revenue in any given period may vary due to the intermittent nature of projects and changes in macroeconomic conditions. See “Risk Factors — Risks Related to Our Business and Strategy — Our revenue may fluctuate, which may result in a high degree of variability in our results of operations and make it difficult for us to plan based on our future outlook and to forecast our future performance.”

In addition, our operating results are impacted to some degree by seasonality, with the second and fourth quarters traditionally showing an increase in revenue. We believe this increase is associated with our end-use customers’ maintenance schedules and timing of capital projects.

66

As a result, comparing our operating results on a period-to-period basis may not be meaningful and historical results may not be indicative of future performance. The following table sets forth the unaudited quarterly consolidated results of operations data for each of the quarters presented:

	Three Months ended
	2012												2013
	March 31			June 30			Sept. 30			Dec. 31			March 31			June 30			Sept. 30			Dec. 31
	($ in thousands)
Revenue:
Product	$	14,155		$	14,043		$	15,662		$	16,529		$	16,170		$	21,801		$	20,833		$	23,253
Research services		742			713			640			969			835			1,177			1,047			978
Total revenue		14,897			14,756			16,302			17,498			17,005			22,978			21,880			24,231
Cost of revenue:
Product		15,967			16,064			17,347			20,647			16,611			18,876			17,769			20,143
Research services		375			353			278			390			356			571			531			506
Gross profit (loss)		(1,445	)		(1,661	)		(1,323	)		(3,539	)		38			3,531			3,580			3,582
Operating expenses:
Research and development		1,301			1,309			1,389			1,143			1,235			1,178			1,387			1,359
Sales and marketing		2,142			2,483			2,387			1,552			2,040			2,439			2,505			2,287
General and administrative		2,647			3,379			2,227			3,046			2,788			2,552			4,353			3,140
Write-off of construction in progress		—			—			—			—			—			—			—			3,440
Total operating expenses		6,090			7,171			6,003			5,741			6,063			6,169			8,245			10,226
Income (loss) from operations		(7,535	)		(8,832	)		(7,326	)		(9,280	)		(6,025	)		(2,638	)		(4,665	)		(6,644	)
Other income (expense):
Interest expense		(2,110	)		(3,447	)		(1,513	)		(14,720	)		3,366			(15,620	)		(8,039	)		(10,306	)
Gain on extinguishment of convertible notes		—			—			—			—			8,898			—			—			—
Loss on exchange of convertible notes		—			—			—			—			(5,212	)		(485	)		—			—
Debt extinguishment costs		—			—			(1,379	)		—			—			—			—			—
Costs associated with postponed public offering		—			—			—			—			—			(241	)		—			—
Total other income (expense), net		(2,110	)		(3,447	)		(2,892	)		(14,720	)		7,052			(16,346	)		(8,039	)		(10,306	)
Net income (loss)	$	(9,645	)	$	(12,279	)	$	(10,218	)	$	(24,000	)	$	1,027		$	(18,984	)	$	(12,704	)	$	(16,950	)

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We achieved positive Adjusted EBITDA in the three months ended June 30, 2013 and have sustained a positive quarterly Adjusted EBITDA through the three months ended December 31, 2013. The following table sets forth a reconciliation of net income (loss) to Adjusted EBITDA for the periods presented:

	Three Months Ended
	2012												2013
	March 31			June 30			Sept. 30			Dec. 31			March 31			June 30			Sept. 30			Dec. 31
	($ in thousands)
Net income (loss)	$	(9,645	)	$	(12,279	)	$	(10,218	)	$	(24,000	)	$	1,027		$	(18,984	)	$	(12,704	)	$	(16,950	)
Interest expense(1)		2,110			3,447			1,513			14,720			(3,366	)		15,620			8,039			10,306
Depreciation and amortization		2,142			2,346			2,564			2,632			2,469			2,479			2,483			2,630
Loss on disposal of assets		—			—			—			2,489			—			—			—			230
Stock-based compensation(2)		299			431			438			486			495			510			2,916			505
Gain on extinguishment of convertible notes		—			—			—			—			(8,898	)		—			—			—
Loss on exchange of convertible notes		—			—			—			—			5,212			485			—			—
Debt extinguishment costs		—			—			1,379			—			—			—			—			—
Costs associated with postponed public offering		—			—			—			—			—			241			—			—
Write-off of construction in progress		—			—			—			—			—			—			—			3,440
Adjusted EBITDA	$	(5,094	)	$	(6,055	)	$	(4,324	)	$	(3,673	)	$	(3,061	)	$	351		$	734		$	161

(1) Interest expense consists primarily of fair market value adjustments related to our subordinated notes, convertible notes and the issuance of our Series C warrants, subordinated note and convertible note issuance costs, the amortization of the subordinated note debt discount and imputed interest on our obligations under our cross license agreements with Cabot Corporation.

(2) Represents non-cash stock-based compensation related to stock option grants.

Liquidity and Capital Resources

Overview

We have experienced significant losses from inception, have an accumulated deficit of $332.8 million as of December 31, 2013 and have substantial ongoing cash flow commitments including debt maturities of $19.8 million in September 2014 and $0.5 million in December 2014. We have invested significant resources to commercialize aerogel technology and to build a manufacturing infrastructure capable of supplying aerogel products at the volumes and costs required by our customers. We are currently experiencing rapid growth as we gain share in our target markets.

Our current financial forecast anticipates continued annual revenue growth, increased gross profit and improving annual cash flows from operations. However, our line of credit agreement expires in July 2014 and we are required to repay $19.8 million upon maturity of the subordinated notes in September 2014. We are actively pursuing sources of new financing, including this offering, to replace the subordinated notes and line of credit upon maturity.

We believe that our existing cash and net proceeds from this offering will be sufficient (i) to fund the design, development and construction of our third production line in East Providence to expand our production capacity, (ii) to repay amounts outstanding under our subordinated notes and line of credit, and (iii) to fund a portion of the design, development and construction of a second production plant in Europe or Asia. We expect to supplement the funds available to us from this offering with anticipated cash flows from operations, local

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government grants and available debt financing to provide the capital required to complete the first production line in our second facility. We will need to pursue alternative sources of financing, including additional issuance of debt or private equity, if this offering is not completed.

Primary Sources of Liquidity

As of December 31, 2013, we had $1.6 million of cash. We have had significant capital expenditures associated with the construction and build out of our East Providence facility. Because our cash flow from operations has been unable to finance these expenditures, we have turned to additional sources of capital discussed below in order to provide us with the necessary liquidity.

In March 2011, we entered into a $10.0 million revolving credit facility with Silicon Valley Bank. Due to a borrowing limitation under the terms of the credit facility, the effective amount available to us under the credit facility is $8.6 million, of which $6.4 million remained available to us as of December 31, 2013 after giving effect to the $1.0 million drawn on the line of credit and the $1.2 million of outstanding letters of credit. As of April 15, 2014, we had $1.5 million drawn on the line of credit and $1.2 million of outstanding letters of credit. Interest on amounts outstanding under the revolving credit facility is equal to the greater of the prime rate or 4% per annum, plus 1.0% per annum. In addition, we are required to pay a quarterly unused revolving line facility fee of 0.5% per annum of the average unused portion of the revolving credit facility. The revolving credit facility will mature on July 27, 2014. See “Description of Certain Indebtedness.”

In December 2010, we entered into a subordinated note and warrant purchase agreement with affiliates of Piper Capital LLC and other investors and issued an aggregate of $10.0 million principal amount of subordinated notes. Twice in June 2011, and in December 2011, June 2012, September 2012 and March 2013, we amended the subordinated note and warrant purchase agreement to revise the maturity date and other terms in connection with the various issuances of our convertible notes. The subordinated notes bear interest at the rate of 20% per annum and are required to be repaid upon the earlier of: (i) September 30, 2014, (ii) the first anniversary of the completion of this offering or (iii) the last business day prior to the date that any of our preferred stock is redeemed. As of December 31, 2013, the total outstanding principal and accrued interest under the subordinated notes was $17.3 million. See “Description of Certain Indebtedness.”

Our recurring net losses taken together with the maturity of our subordinated notes and the expiration of our revolving credit facility have caused our independent registered accounting firm to express doubt about our ability to continue as a going concern. We plan to repay our subordinated notes and borrowings under our revolving credit facility with a portion of the net proceeds from this offering.

From June 2011 through April 15, 2014, we have issued convertible notes with an aggregate principal amount outstanding and accrued but unpaid interest of $103.1 million. These convertible notes accrue interest at 8% per annum. Principal and interest of $0.5 million is due and payable in December 2014 and the remainder is due at various dates during 2016. The unpaid principal amount plus accrued interest of the convertible notes will automatically convert into common stock upon the closing of the offering made hereby at a conversion price equal to 62.5% of the price to the public in this offering. See “Description of Certain Indebtedness.”

Analysis of Cash Flow

The following table summarizes our cash flows for the periods indicated:

	Year Ended December 31
	2011			2012			2013
	($ in thousands)
Net cash provided by (used in):
Operating activities	$	(24,153	)	$	(25,879	)	$	(13,688	)
Investing activities		(31,872	)		(9,785	)		(3,329	)
Financing activities		40,466			25,766			17,248
Net increase (decrease) in cash		(15,559	)		(9,898	)		231
Cash, beginning of period		26,800			11,241			1,343
Cash, end of period	$	11,241		$	1,343		$	1,574

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Net Cash Used in Operating Activities

Our net cash used in operating activities in 2013 was $13.7 million and was primarily due to our net loss of $47.6 million adjusted for non-cash items of $45.5 million (including depreciation and amortization of $10.1 million, write-off of construction in progress of $3.4 million, loss on disposal of assets of $0.2 million, debt issuance costs and noncash interest expenses of $1.0 million, write-off of costs associated with a postponed public offering of $0.2 million, accretion of debt to fair value of $18.7 million, loss on exchange of convertible notes of $5.7 million, issuance of Series C preferred stock warrants in connection with senior convertible notes of $10.7 million, and stock compensation expense of $4.4 million, partially offset by a gain on extinguishment of convertible notes of $8.9 million) and the net decrease in cash from changes in operating assets and liabilities of $11.6 million. This decrease in cash from changes in operating assets and liabilities was primarily due to increases in accounts receivable of $4.8 million, increases in inventories of $0.5 million, increases in prepaid expenses and other assets of $0.3 million, decreases in accounts payable of $1.7 million, decreases in deferred revenue of $0.6 million and a decrease in other liabilities of $6.0 million, partially offset by an increase in accrued expenses of $2.3 million. The increases in accounts receivable and inventory balances are primarily driven by the increase in product revenue and the increase in accrued expenses was due to the accrual of non-equity incentive compensation. The decrease in other liabilities was due to payments made pursuant to our cross license agreement with Cabot Corporation.

Our net cash used in operating activities in 2012 was $25.9 million and was primarily due to our net loss of $56.1 million adjusted for non-cash items of $37.0 million (including depreciation and amortization of $9.7 million, loss on disposal of assets of $2.5 million, debt issuance costs and noncash interest expenses of $3.0 million, accretion of debt to fair value of $18.7 million, stock compensation expense of $1.7 million, and loss on extinguishment of debt of $1.4 million) and a net decrease in cash due to changes in operating assets and liabilities of $6.6 million. This decrease in cash from changes in operating assets and liabilities was primarily due to an increase in accounts receivable of $6.8 million and a decrease in other liabilities of $6.0 million, partially offset by decreases in inventories of $3.2 million, increases in accounts payable of $1.7 million, increases in accrued expenses of $1.1 million, and increases in deferred revenue of $0.3 million. The increase in accounts receivable was primarily driven by the increase in our product revenue, while the decrease in other liabilities was due to payments made pursuant to our cross license agreement with Cabot Corporation.

Our net cash used in operating activities in 2011 was $24.2 million and was primarily due to our net loss of $32.8 million adjusted for non-cash items of $21.0 million (including depreciation and amortization of $7.5 million, debt issuance costs and noncash interest expenses of $3.5 million, write-off of costs associated with a postponed public offering of $3.4 million, write-off of costs associated with a loan application of $0.6 million, accretion of debt to fair value of $4.8 million, stock compensation expense of $1.1 million, and provision for accounts receivable of $0.1 million) and a net decrease in cash due to changes in operating assets and liabilities of $12.2 million. This decrease in cash from changes in operating assets and liabilities was primarily due to increases in inventories of $7.3 million, increases in prepaid expenses and other assets of $0.1 million, decreases in accounts payable of $0.7 million, decreases in accrued expenses of $0.7 million, and a decrease in other liabilities of $6.8 million, partially offset by decreases in accounts receivable of $2.9 million and increases in deferred revenue of $0.5 million. The decrease in accounts receivable and increase in inventories were primarily driven by a decrease in project-based revenue during the year, while the decrease in other liabilities was due to payments made pursuant to our cross license agreement with Cabot Corporation.

Net Cash Used in Investing Activities

Net cash used in investing activities is primarily related to capital expenditures to support our growth. For the years ended December 31, 2011 and 2012, investing activities also included changes in the balance of restricted cash. For the year ended December 31, 2011, investing activities also included proceeds from sales and maturities of our marketable securities.

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Net cash used in investing activities for 2013 totaled $3.3 million and included capital expenditures primarily for machinery and equipment to improve the throughput and efficiency of our East Providence manufacturing operations.

Net cash used in investing activities for 2012 totaled $9.8 million and included capital expenditures of $10.2 million for machinery and equipment, primarily related to the build-out of our third manufacturing line at our East Providence facility which is not yet in service, offset, in part, by a decrease in restricted cash of $0.5 million.

Net cash used in investing activities for 2011 totaled $31.9 million and included capital expenditures of $36.3 million for machinery and equipment, primarily related to the build-out of our second manufacturing line at our East Providence facility, offset, in part, by net proceeds from the sale and maturities of marketable securities of $4.0 million and by a decrease in restricted cash of $0.4 million.

Net Cash Provided by Financing Activities

Cash flows from financing activities primarily include net proceeds from issuances of senior convertible notes and convertible notes and net borrowings under our revolving credit facility.

Net cash provided by financing activities in 2013 totaled $17.2 million and included $18.5 million in proceeds from the issuance of senior convertible notes, less $0.3 million in net repayments under our revolving credit facility and $0.9 million of payments of financing costs.

Net cash from financing activities in 2012 totaled $25.8 million and included $24.9 million in proceeds from the issuance of convertible notes and $1.3 million in net borrowings under our revolving credit facility, less $0.4 million of payments of financing costs.

Net cash from financing activities in 2011 totaled $40.5 million and included $45.0 million in proceeds from the issuance of convertible notes, less $3.4 million of payments of deferred offering costs, $0.8 million of payments of financing costs, and $0.2 million of repayments of borrowings under long-term debt.

Capital Spending and Future Capital Requirements

We have made capital expenditures primarily to develop and expand our manufacturing capacity. Our capital expenditures totaled $36.3 million in 2011, $10.2 million in 2012 and $3.3 million in 2013. As of December 31, 2013, we had capital commitments of $0.6 million, which included commitments for which we have entered into contracts as well as commitments authorized by our Board of Directors. These commitments relate to the improvement of our existing production lines and the engineering and development of our third production line in the East Providence facility. These commitments consist of engineering costs, equipment costs, construction costs and related financing costs. We plan to fund these capital commitments from available cash, available credit under our revolving credit facility with Silicon Valley Bank and the proceeds from this offering.

We have funded our capital expenditures related to design, development and construction of our existing manufacturing facility in East Providence with cash on hand and the proceeds of our financings to date. We currently estimate that design, development and construction of our third production line in the East Providence facility will require additional expenditures of $30 million. We intend to fund capital expenditures related to design, development and construction of our planned second manufacturing facility with the remaining proceeds from this offering, cash flow from operations, local government grants and debt financings. We estimate that the total expenditures for the first production line in our second manufacturing facility will be approximately $80 million to $100 million. See “Risk Factors—Risks Related to Our Business and Strategy—We will require significant additional capital to pursue our growth strategy beyond the construction of our third line in our East Providence facility, but we may not be able to obtain additional financing on acceptable terms or at all.”

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We expect to make approximately $2.7 million in capital expenditures for environmental control facilities in 2014, most of which relate to emission control equipment to support the addition of our planned third production line.

Contractual Obligations and Commitments

The following table summarizes our contractual obligations as of December 31, 2013, under contracts that provide for fixed and determinable payments over the periods indicated:

Contractual Obligations(1)	Total		Less than 1 Year		1-3 Years		3-5 Years		More than 5 Years
	($ in thousands)
Purchase order commitments	$	6,848	$	6,848	$	—	$	—	$	—
Operating leases		2,842		934		1,822		79		7
Capital leases		278		97		181		—		—
Revolving Credit Facility		1,000		1,000		—		—		—
Subordinated Notes		19,834		19,834		—		—		—
Accrued Asset Retirement Obligations		1,136		—		1,136		—		—
Total	$	31,938	$	28,713	$	3,139	$	79	$	7

(1) The contractual obligations table excludes repayment of our convertible notes, all of which will be automatically converted into shares of our common stock upon closing of the offering made hereby.

Operating and Capital Leases

We lease our office space for our corporate offices in Northborough, Massachusetts, which expires in 2016, and warehouse space and land nearby our East Providence facility, which expire at various dates from 2016 through 2021, under non-cancelable operating lease agreements. See “Business — Facilities.” We also lease vehicles and equipment under non-cancelable capital leases that expire at various dates.

Revolving Credit Facility

In March 2011, we entered into a $10.0 million revolving credit facility, as subsequently amended, with Silicon Valley Bank, of which we could have drawn $8.6 million as of December 31, 2013. As of December 31, 2013, we had $1.0 million outstanding under the revolving credit facility. Interest on amounts outstanding under the revolving credit facility is equal to the greater of the prime rate or 4% per annum, plus 1.0% per annum. In addition, we are required to pay a quarterly unused revolving line facility fee of 0.5% per annum of the average unused portion of the revolving credit facility. The revolving credit facility will mature on July 27, 2014. See “Description of Certain Indebtedness.”

Subordinated Notes

On December 29, 2010, we issued secured subordinated promissory notes, as subsequently amended, for aggregate proceeds of $10.0 million. The notes are collateralized by certain of our assets at our East Providence facility. The term notes bear interest at 20% per annum, and all accrued interest on the notes is compounded by adding it to the principal of the subordinated notes on a semi-annual basis commencing on June 30, 2011 and continuing until the last such date to occur prior to maturity. The subordinated notes are required to be repaid upon the earlier of: (i) September 30, 2014, (ii) the first anniversary of the completion of this offering or (iii) the last business day prior to the date that any of our preferred stock is redeemed. The noted contractual obligation reflects the balance of principal and accrued interest anticipated to be due on September 30, 2014. See “Description of Certain Indebtedness.”

Accrued Asset Retirement Obligations

We have asset retirement obligations arising from requirements to perform certain asset retirement activities at the termination of our Northborough facility lease and upon disposal of certain machinery and equipment. The liability was initially measured at fair value and subsequently adjusted for accretion expense and changes in the

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amount or timing of the estimated cash flows. The corresponding asset retirement costs are capitalized as part of the carrying amount of the related long-lived asset and depreciated over the asset’s remaining useful life.

Off Balance Sheet Arrangements

Since inception, we have not engaged in any off balance sheet activities as defined in Item 303(a)(4) of Regulation S-K.

Recent Accounting Pronouncements

On April 5, 2011, the Jump-Start Our Business Startups Act (the JOBS Act) was signed into law. The JOBS Act contains provisions that, among other things, reduce certain reporting requirements for an “emerging growth company.” As an emerging growth company, we have elected to not take advantage of the extended transition period afforded by the JOBS Act for the implementation of new or revised accounting standards, and as a result, will comply with new or revised accounting standards on the relevant dates on which adoption of such standards is required for non-emerging growth companies.

Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists

In July 2013, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (ASU 2013-11). The amendments in ASU 2013-11 require an entity to present an unrecognized tax benefit in the financial statements as a reduction to a deferred tax asset for a net operating loss (“NOL”) carryforward, a similar tax loss or a tax credit carryforward except when: (1) An NOL carryforward, a similar tax loss or a tax credit carryforward is not available as of the reporting date under the governing tax law to settle taxes that would result from the disallowance of the tax position; or (2) the entity does not intend to use the deferred tax asset for this purpose (provided that the tax law permits a choice). If either of these conditions exists, an entity should present an unrecognized tax benefit in the financial statements as a liability and should not net the unrecognized tax benefit with a deferred tax asset. The amendments in this ASU are effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The amendments should be applied prospectively to all unrecognized tax benefits that exist at the effective date. Retrospective application is permitted. The adoption of this guidance did not have any impact on the Company’s consolidated financial statements

Presentation of Amounts Reclassified Out of Accumulated Other Comprehensive Income

In February 2013, the FASB issued guidance for reporting of amounts reclassified out of accumulated other comprehensive income. The revised guidance requires reporting the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income if the amount being reclassified is required to be reclassified in its entirety to net income. For other amounts that are not required to be reclassified in their entirety to net income in the same reporting period, an entity is required to cross-reference other disclosures that provide additional detail about these amounts. The amendments do not change the current requirements for reporting net income or other comprehensive income in financial statements. The guidance was effective prospectively for reporting periods beginning after December 15, 2012. Early adoption was permitted. The adoption of this guidance did not have any impact on the Company’s consolidated financial statements.

Critical Accounting Policies and Estimates

Our financial statements are prepared in accordance with accounting principles generally accepted in the United States of America. The preparation of our financial statements and related disclosures requires us to make estimates, assumptions and judgments that affect the reported amount of assets, liabilities, revenue, costs and expenses and related disclosures. We believe that the estimates, assumptions and judgments involved in the accounting policies described below have the greatest potential impact on our financial statements; and therefore,

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we consider these to be our critical accounting policies. Accordingly, we evaluate our estimates and assumptions on an ongoing basis. Our actual results may differ from these estimates under different assumptions and conditions. See note 2 to our consolidated financial statements included elsewhere in this prospectus for information about these critical accounting policies, as well as a description of our other significant accounting policies.

Revenue Recognition

We recognize product revenue from the sale of our line of aerogel products and research services revenue upon delivery of research and development services, including under contracts with various agencies of the U.S. government. Revenue is recognized when all of the following criteria are met: persuasive evidence of an arrangement exists, the price to the buyer is fixed or determinable, delivery has occurred or services have been provided and collectability is reasonably assured. Product revenue is recognized upon transfer of title and risk of loss, which is generally upon shipment or delivery. In general, our customary shipping terms are FOB shipping point. Products are typically delivered without significant post-sale obligations to customers other than standard warranty obligations for product defects. We provide warranties for our products and record the estimated cost within cost of sales in the period that the revenue is recorded. Our standard warranty period extends one to two years from the date of sale, depending on the type of product purchased. Our warranties provide that our products will be free from defects in material and workmanship, and will, under normal use, conform to the specifications for the product. For the years ended December 31, 2011, 2012 and 2013, warranty charges have been insignificant.

Research services revenue is derived from the execution of contracts awarded by the U.S. federal government or other government agencies and other institutions. Our research and development arrangements require us to provide research in which we investigate new applications of aerogel insulation. We record revenue earned on research services contracts using the percentage-of-completion method in two ways: (1) for firm-fixed-price contracts, we accrue that portion of the total contract price that is allocable, on the basis of our estimates of costs incurred to date to total contract cost; (2) for cost-plus-fixed-fee contracts, we record revenue that is equal to total payroll cost incurred times a stated factor plus reimbursable expenses, to a stated upper limit. The primary cost in these arrangements is the labor effort expended in completing the research and the only deliverable other than labor hours expended is the reporting of the research results to the customer. Because the input measure of labor hours expended is also reflective of the output measure, it is a reliable means to measure the extent of progress towards completion. Contract costs and rates used to allocate overhead to contracts are subject to audit by the respective contracting government agency. Revisions in cost estimates and fees during the course of the contract are reflected in the accounting period in which the facts that require the revisions become known.

Stock-based Compensation

We maintain an equity incentive plan pursuant to which our board of directors may grant qualified and nonqualified stock options to officers, key employees and others who provide or have provided service to us. We measure the costs associated with stock option grants based on their estimated fair value at date of grant. We recognize the costs of options as service or performance conditions are met. Future expense amounts for any particular quarterly or annual period could be affected by changes in our assumptions or changes in market conditions. Stock-based compensation is included in cost of revenue and operating expenses as set forth below:

	Year Ended December 31
	2011		2012		2013
	($ in thousands)
Product cost of revenue	$	195	$	221	$	496
Operating expenses:
Research and development		111		112		267
Sales and marketing		164		384		727
General and administrative		594		937		2,936
Total	$	1,064	$	1,654	$	4,426

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We use the Black-Scholes option-pricing model to estimate the fair value of stock-based awards. The determination of the estimated fair value of stock-based awards is based on a number of complex and subjective assumptions. These assumptions include the determination of the estimated fair value of the underlying security, the expected volatility of the underlying security, a risk-free interest rate, the expected term of the option, and the forfeiture rate for the award class. The following assumptions were used to estimate the fair value of the option awards:

	Year Ended December 31
	2011			2012			2013
Weighted-average assumptions:
Expected term (in years)		6.05			6.02			5.47
Expected volatility		49.33	%		58.06	%		48.99	%
Risk free rate		2.06	%		0.95	%		1.69	%
Expected dividend yield		—	%		—	%		—	%

• The expected term represents the period that our stock-based awards are expected to be outstanding and is determined using the simplified method described in ASC Topic 718, Compensation — Stock Compensation, for all grants. We believe this is a better representation of the estimated life than our actual limited historical exercise behavior.

• For the years ended December 31, 2011, 2012 and 2013, the expected volatility is based on the weighted-average volatility of up to six companies within various industries that we believe are similar to our own.

• The risk-free interest rate is based on U.S. Treasury zero-coupon issues with a remaining term equal to the expected life assumed at the date of grant.

• We use an expected dividend yield of zero, since we do not intend to pay cash dividends on our common stock in the foreseeable future, nor have we paid dividends on our common stock in the past.

As share-based compensation expense is recognized based on awards ultimately expected to vest, it has been reduced for an estimated forfeiture rate of 3% for the years ended December 31, 2011, 2012 and 2013. Forfeitures are required to be estimated at the time of grant and revised, if necessary, in subsequent periods, if actual forfeitures differ from those estimates. Forfeitures were estimated based on voluntary termination behavior as well as analysis of actual option forfeitures.

For performance-based stock options issued during the year ended December 31, 2013, we used a Monte Carlo simulation model to estimate the number of options we expect to remain outstanding and eligible for vesting upon completion of an IPO, including this offering. The simulation model is based on a number of complex assumptions including the terms of the performance condition, the value of our common stock at the time of our IPO, the expected time from the date of grant to our IPO, and expected volatility. The number of options expected to remain outstanding and eligible for vesting upon completion of our IPO was estimated to be 96.8% and 97.4% of the options granted at August 7, 2013 and December 20, 2013, respectively. The compensation cost of these performance-based options was determined by multiplying the Black-Scholes estimate of grant date fair value by the percentage of options expected to remain outstanding and eligible for vesting upon completion of our IPO.

As of December 31, 2013, there was approximately $10.8 million of total estimated unrecognized compensation cost related to unvested options under our equity incentive plan. There was approximately $3.5 million of total estimated unrecognized compensation cost related to service-based options, which will be recognized over a weighted-average period of 2.65 years. There was approximately $7.3 million of total estimated compensation cost related to performance-based options, of which a portion of the total cost will be recognized upon completion of our IPO and the remainder over the requisite service period.

The assumptions underlying these valuations represent management’s estimates, which involve inherent uncertainties and the application of management’s judgment. As a result, if factors or expected outcomes change

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and we use significantly different assumptions or estimates, our stock-based compensation could be materially different. The most significant input into the Black-Scholes option-pricing model used to value our option grants is the estimated fair value of our common stock. We considered a combination of valuation methodologies, including market and transaction approaches.

Determination of Fair Value

We believe we have used reasonable methodologies and assumptions in determining the fair value of our common stock for financial reporting purposes. Prior to this offering, there was no public market for our common stock. In the absence of a public market for our common stock, the fair value of our common stock underlying our stock options has historically been determined by our board of directors using methodologies consistent with the American Institute of Certified Public Accountants Practice Guide, Valuation of Privately-Held-Company Equity Securities Issued as Compensation. In connection with making this determination, we have engaged third-party valuation advisors to assist us.

The methodologies we have employed to determine the fair value of our common stock have included the market approach and the income approach. These methodologies are used to estimate the enterprise value of the business under various liquidity event scenarios, including an initial public offering by the company and the sale of the company. To support the valuations, we utilized a probability-weighted expected return under those various liquidity scenarios, public guideline companies, our cash flow projections and other assumptions to derive the enterprise value of the business. We then derived the estimated fair value of each class of stock, taking into consideration the rights and preferences of each instrument based on a probability-weighted expected return.

The most significant factors considered in estimating the fair value of our common stock were as follows:

• current business conditions and projections;

• the probability and value of future liquidity scenarios, including an initial public offering by the company and the sale of the company;

• the average equity volatilities of peer companies;

• the market performance of comparable publicly traded companies; and

• U.S. and global capital conditions.

We believe consideration of these factors by our board of directors was a reasonable approach to estimating the fair value of our common stock for the periods considered. Estimating the fair value of our common stock requires complex and subjective judgments, however, and there is inherent uncertainty in our fair value estimates.

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The following table summarizes the number of stock options granted from January 1, 2011 through December 31, 2013, the average per share exercise price of the options and the estimated per share fair value of the options:

Date of Grant	Number of Options Granted			Per Share Exercise Price(1)		Estimated per Share Option Fair Value(2)
January 18, 2011		53,000		$	14.60	$	7.41
January 19, 2011		8,251			14.60		7.41
March 16, 2011		12,401			14.60		7.19
May 18, 2011		131,888			24.40		11.83
August 10, 2011		24,331			24.90		11.70
November 11, 2011		31,036			18.50		9.05
January 23, 2012		11,200			17.80		8.02
March 14, 2012		93,536			17.80		9.85
May 9, 2012		128,600			17.10		9.30
August 8, 2012		15,743			16.20		8.69
November 7, 2012		680,863			7.90		4.23
August 7, 2013		16,056,628	(3)		0.09		0.12
August 7, 2013		56,198,154	(4)		0.09		0.11
December 20, 2013		1,771,277	(5)		0.18		0.17
December 20, 2013		6,199,468	(6)		0.18		0.16
Total		81,416,376

(1) The per share exercise prices of options were established by our board of directors at the time of the grant.

(2) The per share fair values of the options were estimated as of the date of grant using the Black-Scholes option pricing model. This model estimates the fair value by applying a series of factors including the exercise price of the option, a risk-free interest rate, the expected term of the option, expected share price volatility of the underlying common stock and expected dividends on the underlying common stock. The per share fair value of performance-based options has been adjusted to reflect the percentage of options expected to remain outstanding and eligible for vesting upon completion of our IPO as determined by a Monte Carlo simulation. The simulation model is based on a number of complex assumptions including the terms of the performance condition, the value of our common stock at the time of our IPO, the expected time from the date of grant to our IPO, and expected volatility. Additional information regarding our option awards is set forth in note 16 to our audited consolidated financial statements included elsewhere in this prospectus. For financial reporting purposes, we have recorded stock-based compensation expense associated with the August 7, 2013 and December 20, 2013 option grants using a $0.18 per share and a $0.28 per share, respectively, fair value of our common stock as determined by the retrospective valuations described below in “—Grants on August 7, 2013” and “—Grants on December 20, 2013”, respectively.

(3) In connection with this grant, 1,871,928 previously issued options were forfeited by the holders of these options.

(4) These options are performance-based options. Upon our IPO, the number of shares subject to these options shall be reduced, if necessary, such that each holder’s total option holdings shall equal a target percentage of our common stock deemed outstanding immediately prior to the offering. If the number of shares subject to these options is insufficient to achieve the target percentage upon our IPO, we are under no obligation to grant additional options to the holders. The aggregate target percentage for all holders of performance-based options on the date of grant was 13.896%.

(5) In connection with this grant, 94,900 previously issued options were forfeited by the holders of these options.

(6) These options are performance-based options. Upon our IPO, the number of shares subject to these options shall be reduced, if necessary, such that each holder’s total option holdings shall equal a target percentage of our common stock deemed outstanding immediately prior to the offering. If the number of shares subject to these options is insufficient to achieve the target percentage upon our IPO, we are under no obligation to grant additional options to the holders. The aggregate target percentage for all holders of performance-based options issued on the date of grant was 1.488%.

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Based on the mid-point of the price range set forth on the cover of this prospectus, the aggregate intrinsic value of our outstanding stock options as of December 31, 2013 was $         million.

The fair value of our common stock was estimated using the probability-weighted expected return method, or PWERM, which considers the value of preferred and common stock based upon analysis of the future values for equity assuming various future outcomes, including initial public offerings, merger or sale, dissolutions or continued operation as a private company. Accordingly, share value is based upon the probability-weighted present value of the Company based on the possible future events, as well as the rights and preferences of each share class. PWERM is complex as it requires numerous assumptions relating to potential future outcomes of equity, hence, the use of this method can be applied: (i) when possible future outcomes can be predicted with reasonable certainty; and (ii) when there is a complex capital structure (i.e., several classes of preferred and common stock).

Grants from January 18, 2011 through March 16, 2011. On January 18, 2011, our board of directors established the exercise price per share of common stock at $14.60 per share determined by the PWERM method. Our board of directors reaffirmed this exercise price on January 19, 2011 and March 16, 2011 in connection with option grants. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. The significant drivers and weightings for our valuations during this period were: initial public offering, 60%; sale of our company/assets, 20%; remain private, 15%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on May 18, 2011. On May 9, 2011, our board of directors established the exercise price per share of common stock at $24.40 per share determined by the PWERM method. Our board of directors reaffirmed this exercise price on May 18, 2011 in connection with option grants. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. The significant drivers and weightings for our valuations during this period were: initial public offering, 70%; sale of our company/assets 20%; remain private, 5%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on August 10, 2011. On August 10, 2011, our board of directors established the exercise price per share of common stock at $24.90 per share determined by the PWERM method. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples that represented a premium to the top quartile of comparable companies was appropriate and modestly increased such premium. The significant drivers and weighting for our valuations during this period were: initial public offering, 80%; sale of our company/assets, 10%; remain private, 5%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on November 11, 2011. On November 11, 2011, our board of directors established the exercise price per share of common stock at $18.50 per share determined by the PWERM method. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples that represented a premium to the top quartile of comparable companies was appropriate and modestly decreased such premium. The significant drivers and weighting for our valuations during this period were: initial public offering, 80%; sale of our company/assets, 10%; remain private, 5%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants from January 23, 2012 to March 14, 2012. On January 23, 2012 and March 14, 2012, our board of directors established the exercise price per share of common stock at $17.80 per share determined by the

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PWERM method. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples that represented a premium to the top quartile of comparable companies was appropriate. The significant drivers and weighting for our valuations during this period were: initial public offering, 70%; sale of our company/assets, 20%; remain private, 5%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on May 9, 2012. On May 9, 2012, our board of directors established the exercise price per share of common stock at $17.10 per share determined by the PWERM method. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples that represented a premium to the top quartile of comparable companies was appropriate and modestly decreased such premium. The significant drivers and weighting for our valuations during this period were: initial public offering, 70%; sale of our company/assets, 20%; remain private, 5%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on August 8, 2012. On August 8, 2012, our board of directors established the exercise price per share of common stock at $16.20 per share determined by the PWERM method. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples that represented a premium to the top quartile of comparable companies was appropriate and modestly decreased such premium. The significant drivers and weighting for our valuations during this period were: initial public offering, 55%; sale of our company/assets, 40%; remain private, 5%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on November 7, 2012. On November 7, 2012, our board of directors established the exercise price per share of common stock at $7.90 per share determined by the PWERM method. This valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples that represented a premium to the top quartile of comparable companies was appropriate and modestly decreased such premium. The significant drivers and weighting for our valuations during this period were: initial public offering, 40%; sale of our company/assets, 45%; remain private, 10%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

Grants on August 7, 2013. On August 7, 2013, our board of directors established the exercise price per share of common stock at $0.09 per share determined by the PWERM method. This contemporaneous valuation took into consideration market and general economic events as well as our financial results and other data available at that time, including our issuance of convertible notes and additional preferred equity securities in our March 2013 financing, which was dilutive to existing stockholders. The board adopted a revised set of comparable companies to more accurately reflect the nature of our business. In addition, the board reset our market multiples to fall within the top quartile of the revised set of comparable companies. The significant drivers and weighting for our valuations during this period were: initial public offering, 40%; sale of our company/assets, 45%; remain private, 5%; and dissolution, 10%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

As part of its determination of the fair value of our common stock, our board of directors considered that a valuation dated March 31, 2013 reasonably reflected the per share fair value of our common stock on August 7, 2013. However, given the relative proximity of a subsequent valuation dated September 30, 2013 to the August 7,

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2013 grant date, we concluded that a retrospective valuation of the fair value of our common stock, including all projections, facts and circumstances known to us as of the date of the delivery of the subsequent valuation on January 6, 2014, might have resulted in a fair value of our common stock as of the August 7, 2013 grant date of up to $0.18 per share. For financial reporting purposes, we have recorded stock-based compensation expense associated with the August 7, 2013 option grants using a $0.18 per share fair value of our common stock, as determined by the retrospective valuation.

Grants on December 20, 2013. On December 20, 2013, our board of directors established the exercise price per share of common stock at $0.18 per share determined by the PWERM method. This contemporaneous valuation took into consideration market and general economic events as well as our financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples within the top quartile of comparable companies was appropriate. The significant drivers and weighting for our valuations during this period were: initial public offering, 50%; sale of our company/assets, 30%; remain private, 15%; and dissolution, 5%. The estimated fair value of one share of common stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability-weighted value per share.

As part of its determination of the fair value of our common stock, our board of directors considered that a valuation dated September 30, 2013 reasonably reflected the per share fair value of our common stock on December 20, 2013. However, given the relative proximity of a subsequent valuation dated December 31, 2013 to the December 20, 2013 grant date, we concluded that a retrospective valuation of the fair value of our common stock, including all projections, facts and circumstances known to us as of the date of the delivery of the subsequent valuation on March 10, 2014, might have resulted in a fair value of our common stock as of the December 20, 2013 grant date of up to $0.28 per share. For financial reporting purposes, we have recorded stock-based compensation expense associated with the December 20, 2013 option grants using a $0.28 per share fair value of our common stock, as determined by the retrospective valuation.

Valuation models require the input of highly subjective assumptions. There are significant judgments and estimates inherent in the determination of these valuations. These judgments and estimates include assumptions regarding our future performance, the time to undertaking and completing an initial public offering or other liquidity event, as well as determinations of the appropriate valuation methods. If we had made different assumptions, our stock-based compensation expense, net income (loss) and net income (loss) per share could have been significantly different. The foregoing valuation methodologies are not the only valuation methodologies available and will not be used to value our common stock once this offering is complete. We cannot make assurances regarding any particular valuation of our common stock.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.

We recognize the effect of income tax positions only if those positions are more likely than not of being sustained. We account for uncertain tax positions using a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. Differences between tax positions taken in a tax return and amounts recognized in the financial statements are recorded as adjustments to income taxes payable or receivable, or adjustments to deferred taxes, or both. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. We recognize penalties and interest related to recognized tax positions, if any, as a component of income tax expense.

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Management’s judgment and estimates are required in determining our tax provision, deferred tax assets and liabilities and any valuation allowance recorded against deferred tax assets. We review the recoverability of deferred tax assets during each reporting period by reviewing estimates of future taxable income, future reversals of existing taxable temporary differences and tax planning strategies that would, if necessary, be implemented to realize the benefit of a deferred tax asset before expiration. We have recorded a full valuation allowance against our deferred tax assets due to the uncertainty associated with the utilization of the net operating loss carryforwards. In assessing the realizability of deferred tax assets, we consider all available evidence, historical and prospective, with greater weight given to historical evidence, in determining whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of our deferred tax assets generally is dependent upon generation of future taxable income.

Fair Value Option and Fair Value Measurements

ASC Subtopic 825-10 provides entities with an option to measure many financial instruments and certain other items at fair value. Under this guidance, unrealized gains and losses on items for which the fair value option has been elected are reported in earnings each reporting period. As a result of electing this option, we record our subordinated notes and convertible notes at fair value in order to measure these liabilities at an amount that more accurately reflects the economics of these instruments.

The fair value of the convertible notes was determined by utilizing a probability weighted discounted cash flow analysis. This analysis determined the amount to be paid on the notes in either cash or shares at the occurrence of certain events in which the convertible notes would be converted into shares of our common stock or would be repaid to the lender in cash. The probability weighted discounted cash flow analysis utilized assumptions related to the probability of each of the various events occurring and discount rates.

Based upon the above we have determined that the valuation of the subordinated notes and convertible notes is a Level 3 valuation as the valuation utilized several unobservable inputs. Accordingly, valuations of subordinated notes and convertible notes require the input of highly subjective assumptions to create a probability weighted discounted cash flow analysis. These assumptions include significant judgments and estimates inherent in the determination of these valuations. These significant judgments include the time to and the probability of completing an initial public offering or other liquidity event and the appropriate valuation methods. Changes to the assumptions and estimates could have a significant impact on the fair value of our subordinated notes and convertible notes, interest expense, net income (loss) and net income (loss) per share.

Impairment of Long-Lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future undiscounted net cash flows expected to be generated by the asset. If the carrying amount of an asset exceeds its estimated undiscounted future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset exceeds the fair value of the asset. Fair value is determined through various valuation techniques including discounted cash flows models, quoted market values and third-party independent appraisals, as considered necessary.

Redeemable Convertible Preferred Stock

Our redeemable convertible preferred stock was classified as temporary equity and shown net of issuance costs at December 31, 2012. We recognized changes in the redemption value and adjusted the carrying amount of the redeemable convertible preferred stock to equal the redemption value at the end of each reporting period.

We accounted for the 2013 amendment to redeemable convertible preferred stock as an extinguishment as the fair value of the shares immediately after the amendment was significantly different from the fair value of the

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instrument immediately before the amendment. The change in fair value upon extinguishment was recorded in additional paid-in capital.

Qualitative and Quantitative Disclosures about Market Risk

Market risk represents the risk of loss that may impact our financial position due to adverse changes in financial market prices and rates. Our market risk exposure results primarily from fluctuations in interest rates as well as from inflation. In the normal course of business, we are exposed to market risks, including changes in interest rates which affect our line of credit under our revolving credit facility as well as cash flows. We may also face additional exchange rate risk in the future as we expand our business internationally.

Interest Rate Risk

We are exposed to changes in interest rates in the normal course of our business. At December 31, 2013, we had unrestricted cash of $1.6 million. These amounts were held for working capital purposes and were invested primarily in government-backed securities. Due to the short-term nature of these investments, we believe that we do not have any material exposure to changes in the fair value of our cash as a result of changes in interest rates.

As of December 31, 2013, our outstanding debt also includes capital leases and term loans that have fixed interest rates and a revolving line of credit. In June 2013, the Company renewed its line of credit agreement, extended the maturity date of the facility to June 27, 2014 and increased its available borrowing base. In March 2014, the Company further extended the maturity date to July 27, 2014. As of December 31, 2013, we had $1.0 million outstanding under the revolving credit facility and outstanding letters of credit of $1.2 million. Interest on amounts outstanding under the revolving credit facility is equal to the greater of the prime rate or 4% per annum, plus 1.0% per annum. The amount available to us under the line of credit at December 31, 2013 was $6.4 million after giving effect to a borrowing limitation, the $1.0 million drawn on the line of credit and the $1.2 million of outstanding letters of credit.

Inflation Risk

Although we expect that our operating results will be influenced by general economic conditions, we do not believe that inflation has had a material effect on our results of operations during the periods presented. However, our business may be affected by inflation in the future.

Foreign Currency Exchange Risk

We are subject to inherent risks attributed to operating in a global economy. Principally all of our revenue, receivables, purchases and debts are denominated in U.S. dollars. Although our international operations are currently not significant compared to our operations in the United States, we expect to expand our international operations in the long-term. An expansion of our international operations will increase our potential exposure to fluctuations in foreign currencies.

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BUSINESS

Overview

We are an energy technology company that designs, develops and manufactures innovative, high-performance aerogel insulation used primarily in large-scale energy infrastructure facilities. We believe our aerogel blankets deliver the best thermal performance of any widely used insulation product available on the market today and provide a combination of performance attributes unmatched by traditional insulation materials. Our products provide two to five times the thermal performance of widely used traditional insulation in a thin, easy-to-use and durable blanket form. Our end-use customers select our products where thermal performance is critical, and to save money, reduce energy use, preserve operating assets and protect workers.

Our technologically advanced products are targeted at the estimated $2.8 billion annual global market for energy infrastructure insulation materials and which Freedonia estimates is expected to grow to $3.5 billion in 2018. Our aerogel insulation has undergone rigorous technical validation and is used by many of the world’s largest oil producers and the owners and operators of refineries, petrochemical plants, LNG facilities and power generating assets, such as ExxonMobil, Formosa Petrochemical, Pemex Gas and NextEra Energy Resources. Our products replace traditional insulation in existing facilities during regular maintenance, upgrades and capacity expansions. In addition, we are increasingly being specified for use in new-build energy infrastructure facilities.

We introduced our two key product lines, Pyrogel and Cryogel in 2008. Our product revenue has grown from $17.2 million in 2008 to $82.1 million in 2013, representing a compound annual growth rate of 37%. We have sold more than $250 million of our products globally, representing an installed base of more than 100 million square feet of insulation. We believe that this initial success positions us for future growth and continued gain in market share.

We currently target our sales efforts in the energy infrastructure market, where we believe our products have the highest value applications. As we continue to expand our production capacity and enhance our technology, we believe we will have opportunities to address additional high value applications in the estimated $37 billion global insulation market.

We have grown our business by forming technical and commercial relationships with industry leaders, which has allowed us to optimize our products to meet the particular demands of targeted market sectors. We have benefited from our technical and commercial relationships with ExxonMobil in the oil refinery and petrochemical sector, with Technip in the offshore oil sector and with NextEra Energy Resources in the power generation sector. We will continue our strategy of working with innovative companies to target and penetrate additional market opportunities. We estimate that we generated 87% of our 2013 product revenue in the energy infrastructure insulation market.

Our patented aerogel and manufacturing technologies are significant assets. Our intellectual property portfolio is supported by 51 issued patents, with an additional 18 pending in the U.S. and foreign jurisdictions in areas related to product design, chemistry and application. As of April 15, 2014, we employed 27 research scientists and process engineers focused on advancing our current aerogel technology and developing next generation aerogel compositions, form factors and manufacturing technologies. Aerogels are complex structures in which 97% of the volume consists of air trapped between intertwined clusters of amorphous silica solids. These extremely low density solids provide superior insulating properties. Although aerogels are usually fragile materials, we have developed innovative and proprietary manufacturing processes that enable us to produce industrially robust aerogel insulation cost-effectively and at commercial scale.

Our products enable compact design, reduce installation time and costs, promote freight and logistics cost savings, reduce system weight and required storage space and enhance job site safety. Our products reduce the incidence of corrosion under insulation, which is a significant maintenance cost and safety issue in energy

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infrastructure facilities. Our products also offer strong fire protection, which is a critical performance requirement in our markets. We believe our array of product attributes provides strong competitive advantages over traditional insulation. Although competing insulation materials may have one or more comparable attributes, we believe that no single insulation material currently available offers all of the properties of our aerogel insulation.

We derived 13% of our 2013 product revenue from the building and construction and other end markets. Customers in these markets use our aerogels for applications as diverse as wall systems, military and commercial aircraft, trains, buses, appliances, apparel, footwear and outdoor gear. While not our core market, we anticipate that we will continue to allocate a modest portion of our manufacturing capacity to serve these markets. Based on the Freedonia Report, we estimate that the building and construction, transportation, appliance, apparel and other industrial insulation markets totaled $34 billion in 2013.

In addition, we continue to perform contract research services for a number of federal and non-federal government agencies, including NASA, National Science Foundation, Defense Advanced Research Projects Agency, U.S. Army, U.S. Navy, U.S. Air Force and the Department of Energy, among others.

For the years ended December 31, 2011, 2012 and 2013, based on shipment destination or research services location, our U.S. revenues were $15.2 million, $19.9 million and $30.2 million, respectively, and our international revenues were $30.8 million, $43.5 million and $55.9 million, respectively.

We manufacture our products using proprietary technology at our facility in East Providence, Rhode Island. We have operated the East Providence facility at high volume and high yield since 2008. We successfully commenced operation of our second production line at this facility at the end of March 2011, which doubled our annual nameplate capacity to 40 million to 44 million square feet of aerogel blankets, depending on product mix.

To address anticipated near and mid-term capacity constraints caused by increasing demand for our products, we are in the process of expanding our production facility. We are in the design and engineering phase of a third production line at our East Providence facility and have procured certain capital equipment with a longer lead-time. We currently expect that this third line will increase our annual nameplate capacity by 25% to 50 million to 55 million square feet and will be completed in the first half of 2015. We plan to construct a second manufacturing facility in Europe or Asia, the location of which will be based on factors including labor and construction costs, availability of governmental incentives, and proximity to raw material suppliers. We anticipate initial operation of a first production line at this facility during 2017.

Company Information

We are a corporation organized under the laws of Delaware. Our predecessor company was incorporated in Delaware in May 2001. In June 2008, we completed a reorganization pursuant to which our predecessor company merged with and into a newly formed Delaware corporation, renamed Aspen Aerogels, Inc.

Industry Background

Demand for energy is correlated with economic activity and global standards of living. As the economies in developing countries grow and become more productive, energy consumption rises. Even with substantial anticipated gains in energy efficiency, the EIA projects in the International Energy Outlook 2013 report that global energy consumption will grow more than 50% over the next several decades. To support this growth in demand, significant investment will continue to be made in the world’s energy infrastructure, and existing infrastructure will likely continue to reflect high levels of utilization.

Markets

Insulation is a material or combination of materials that slows the transfer of heat and is used in a wide variety of applications. The global market for insulation materials was estimated to be $37 billion during 2013, according to Freedonia. There are a variety of insulation materials available in the market, most of which have been in use for over 50 years. Each insulation material has a different set of performance attributes and the extent of its use in a given market is based on the performance and cost criteria applicable to that market.

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Our core market is the energy infrastructure insulation market. This market is global, well-established and includes large and well-capitalized end-users. According to estimates in the Freedonia Report, the worldwide energy infrastructure insulation market totaled $2.8 billion in 2013 and is expected to grow to $3.5 billion in 2018. This market includes companies operating refinery, petrochemical, LNG production and storage and oil production facilities. The market also includes firms operating gas, coal, nuclear, hydro and solar thermal power generating plants. Insulation systems in the energy infrastructure market are designed to maintain hot and cold process piping and storage tanks at optimal temperatures, to protect plant and equipment from the elements and from the risk of fire, and to protect workers. The market is served by a well-organized, well-established, worldwide network of distributors, contractors and engineers.

Insulation demand in the market is composed of demand for insulation associated with new-build construction of facilities, capital expansions and related capital projects, as well as with routine, non-discretionary maintenance programs within existing facilities. Capital expansions and related capital projects in the energy infrastructure market are driven primarily by overall economic growth and projected growth in energy demand. Maintenance programs are essential to optimal operation of processing equipment, to protect workers and to minimize the risk of a catastrophic loss. Accordingly, we believe that demand for insulation for maintenance purposes in comparison to capital projects is less affected by volatility associated with economic cycles and similar macroeconomic factors.

Global energy demand for all forms of energy is expected to increase by 56% from 2010 to 2040, according to the International Energy Outlook 2013 report by the EIA. In order to serve this growing demand, we believe our end-use customers will continue to invest in major energy infrastructure projects. The major end markets that drive demand for our products include:

• Oil Refining: Freedonia has estimated that sales of insulation products to this segment totaled $384 million in 2013, with a projected compound annual growth rate through 2018 of 5.1%. World refining capacity is projected to increase approximately 1.5 MMBbl/d on average per year from 2013 to 2017, according to the September 2013 Barclays CEO Energy-Power Conference presentation by Valero Energy Corporation. We believe the key performance attributes for insulation that differentiates our solutions from competing products in this market are wide temperature range, mitigation of corrosion under insulation and thin profile of our aerogel blankets which allows for compact design, as well as strong fire protection.

• Petrochemical: Freedonia has estimated that sales of insulation products to this segment totaled $484 million in 2013, with a projected compound annual growth rate through 2018 of 5.0%. Worldwide capital spending in the chemistry sector is projected to increase from $413.8 billion in 2012 to $617.5 billion in 2018, at a compounded annual growth rate of 6.9%, according to the Year-End 2013 Chemical Industry Situation and Outlook report by the American Chemistry Council, America’s oldest chemicals trade association. We believe the key performance attributes for insulation that differentiates our solutions from competing products in this market are wide temperature range, mitigation of corrosion under insulation and thin profile of our aerogel blankets which allows for compact design.

• Natural Gas and LNG: Freedonia has estimated that sales of insulation products to this segment totaled $418 million in 2013, with a projected compound annual growth rate through 2018 of 3.4%. As of March 2014, global LNG demand is expected to increase from 28.8 Bcf/d in 2010 to 60.1 Bcf/d in 2025, at a compound annual growth rate of 5.0%, according to the Global LNG Long-Term Outlook Q1 2014 by Wood Mackenzie, a leading independent energy research and consulting firm. We believe the key performance attributes for insulation that differentiates our solutions from competing products in this market are thermal performance at cryogenic conditions, ease of installation and simplified logistics.

• Onshore Oil Production, including Oil Sands: In this segment, our products are mainly used in the Canadian oil sands. Freedonia has estimated that sales of insulation products to this segment totaled $199 million in 2013, with a projected compound annual growth rate through 2018 of 3.7%. Annual production from oil sands activities is projected to increase from 1.8 MMBbl/d in 2012 to 5.2 MMBbl/d in 2030, at a compound annual growth rate of 6.1%, according to the June 2013 Crude Oil Forecasts,

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Markets & Transportation report by the Canadian Association of Petroleum Producers. We believe the key performance attribute for insulation that differentiates our solutions from competing products in this market is the high durability of our aerogel blankets.

• Offshore Oil Production: Our products are mainly used in this segment to provide pipe-in-pipe thermal protection and flow assurance for hydrocarbon production at the seafloor. Freedonia has estimated that sales of insulation products to this segment totaled $81 million in 2013, with a projected compound annual growth rate through 2018 of 4.7%. Our relationships with Technip and other engineering, procurement and construction contractors are critical to the selection of our products for subsea projects. Annual global spending on offshore drilling activities is projected to increase from $97 billion in 2012 to $170 billion in 2019, at a compound annual growth rate of approximately 8.4%, according to the December 2013 Drilling and Production Outlook report by Spears and Associates, Inc., a leading independent oilfield equipment and service company research and consulting firm. We believe the key performance attribute for insulation that differentiates our solutions from competing products for subsea use in this market is the thin profile of our aerogel products which allows for compact design.

• Power Generation: Freedonia has estimated that sales of insulation products to this segment totaled $1.2 billion in 2013, with a projected compound annual growth rate through 2018 of 5.1%. Global net electricity generation is projected to increase by 69% from 21.4 trillion kWh in 2012 to 36.2 trillion kWh in 2035, according to the International Energy Outlook 2013 report by the EIA. We believe the key performance attribute for insulation that differentiates our aerogel products from competing insulation solutions in this market is thermal performance at high temperature.

The following tables illustrate the growing energy insulation end market size by sector and by region in 2010 and 2013, and projected for 2018.

Energy Insulation End Markets - by Sector
($ millions)
	2010		2013		2018
Refinery	$	327	$	384	$	492
Petrochemical		418		484		619
Onshore Oil Production		176		199		239
Offshore Oil Production		69		81		102
Natural Gas and LNG		366		418		494
Power Generation		1,087		1,248		1,600
Total	$	2,443	$	2,814	$	3,546

Energy Insulation End Markets - by Region
($ millions)
	2010		2013		2018
USA	$	415	$	470	$	553
Canada		73		86		104
Latin America		198		226		278
Europe		512		541		603
Asia Pacific		903		1,089		1,485
Middle East Africa		342		402		523
Total	$	2,443	$	2,814	$	3,546

Source: Freedonia Custom Research, Inc.

We are targeting continued expansion of the use of our products within energy infrastructure facilities during regular maintenance, upgrades and expansions. In addition to opportunities to replace traditional insulation at existing facilities, we are also pursuing insulation applications at new-build and large capacity expansion projects

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around the world. Historically, a significant portion of our revenue has been derived from displacing traditional insulation at existing facilities, in particular during periods of planned plant maintenance or upgrades. We believe these maintenance applications will continue to comprise a large portion of our revenue mix.

As our end-use customers gain experience with our products at existing facilities, we believe that more of our customers will also select our products for new-build facility construction and large capacity expansion projects, which we expect to drive significant revenue growth. We expect that growing demand for refined products and LNG, as well as increases in capital spending in the refinery, petrochemical and power generation markets, will result in increased new-build and large capacity expansion project-related demand for our aerogel products. Below we estimate the product revenue opportunity for a new-build or large capacity expansion project in the following energy infrastructure segments:

	Refinery			Liquefaction Plant			Ethylene Plant			Gas-fired Power Plant
Estimated Projected Market Capacity Coming Online		6 MMbbl/d	(1)		100 MMtpa	(2)		10MMtpa	(3)		38,100 MW	(4)
Illustrative Project Size		100,000 Bbl/d	(5)		5.5 MMtpa			1.6 MMtpa			700 MW
Illustrative Single Project Cost	$	2.5B	(6)	$	3.1B	(7)	$	2.8B	(8)	$	0.6B	(9)
Total Insulation Installed Cost as % of Project Cost(10)		1%			3%			1%			1%
Insulation Material as % of Insulation Installed Cost(11)		40%			40%			40%			30%
Illustrative Insulation Material Revenue Opportunity Per Project	$	10mm		$	37mm		$	11mm		$	2mm

(1) Projected global refinery capacity additions from 2014 – 2017. Source: Valero Energy Corporation (September 2013).

(2) Estimated incremental global LNG demand 2014 – 2019. Source: Wood Mackenzie (February 2014). “MMtpa” means one million tonnes per annum. “Tonne” means one metric ton—a metric system unit equivalent to approximately 2,205 pounds.

(3) Forecasted new U.S. ethylene capacity to come online by 2017. Source: ICIS report (July 2013).

(4) Estimated U.S. generation capacity additions of natural gas power plants from 2012 – 2020. Source: EIA 2013 Annual Energy Outlook. “MW” means a megawatt.

(5) “ Bbl” means one stock tank barrel of 42 U.S. gallons liquid volume used herein in reference to crude oil, condensate or natural gas liquids. “Bbl/d” is one Bbl per day.

(6) Estimated average construction cost of $25,000 per barrel of capacity. Source: Oil & Gas Journal (April 2013 – February 2014).

(7) Estimated average construction cost of $561/tonnes per annum, or tpa. Source: International Gas Union (2013).

(8) Estimated average construction cost of $1,769/tpa. Source: Oil & Gas Journal (August 2013 – February 2014), Bloomberg (December 2012).

(9) Estimated average construction cost of $917,000/MW. Source: EIA (2013).

(10) Management estimate of total installed cost, including labor and materials.

(11) Management estimate. Although the cost of the insulation material used in energy infrastructure projects as a percentage of the overall installed cost of insulation on a project may vary depending on a number of factors, management believes that this estimate is consistent with typical industry projects.

These revenue opportunity estimates are generally consistent with our historical experience, other than new-build and large-capacity expansion projects for liquefaction plants, from which we have not previously derived revenue. Over the last several years, a meaningful portion of our revenues has been derived from large capacity expansion projects and new-build facility construction, including:

• $9.1 million of aerogel product revenue for a Canadian oil sands project;

• $4.8 million of aerogel product revenue for a Latin American refinery expansion;

• $3.8 million of aerogel product revenue for a U.S. alternative energy power generation project; and

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• numerous subsea projects totaling $13.3 million over the past three years, which average $1.2 million per project.

In addition, we recently received $14 million of purchase orders for use in a major expansion by an Asian petrochemical company, from which we recognized $              million in revenue in the three month period ended March 31, 2014.

We also sell our products in the building and construction and other end markets, including the supply of fabricated insulation parts to original equipment manufacturers, or OEMs. These global OEMs develop products using our aerogels for applications as diverse as military and commercial aircraft, trains, buses, appliances, apparel, footwear and outdoor gear. While not our core market, we anticipate that we will continue to allocate a modest portion of our manufacturing capacity to serve these markets. We believe the key performance criteria for insulation in these markets includes thermal performance, compact design, durability and fire resistance.

Our Solution

Because insulation is used in a wide variety of demanding applications, insulation materials must satisfy a wide range of performance criteria on a cost-effective basis. We believe that our aerogel technology has allowed us to create superior insulation products for our core markets that will allow us to continue to grow our share of the global insulation market. We believe that the potential for significant technological innovation in traditional insulation materials is limited and that new high-performance materials will be required to meet evolving market requirements for energy efficient insulation systems. Our line of high-performance aerogel blankets is positioned to meet these requirements. Our solution is driven by our innovative and proprietary technology that produces aerogels in a flexible and industrially robust blanket form and is supported by over ten years of research and development dedicated to new aerogel compositions, form factors and manufacturing technologies. We believe our aerogel blankets deliver a superior combination of performance attributes that enable end-users to save money, reduce energy use, preserve operating assets and protect workers across a wide range of applications in our target markets, including:

• Best Thermal Performance. Our aerogel blankets provide the best thermal performance of any widely used insulation product available on the market today and excel in applications where thermal performance requirements are demanding or available space for insulation is constrained. Our products address a wide range of applications within the cryogenic and sub-ambient (down to -200°C), ambient and hot process (up to 650°C) temperature ranges.

• Reduced Corrosion Under Insulation, or CUI. Our Pyrogel XT product line is both hydrophobic and vapor permeable. These attributes have the potential to reduce the incidence of CUI in hot process applications, which we believe provides our end-users with a significant reduction in long-term operating and capital costs. Corrosion of process piping and storage tanks increases the risk of catastrophic system failures. Preventative facility maintenance and related expenses are estimated to cost the petrochemical industry billions of dollars per year. Our products also offer improved thermal performance in insulation systems exposed to the elements or operating in humid environments compared to traditional insulation.

• Compact Design and Faster Installation. Our aerogel blankets reduce insulation system volume by 50% to 80% compared to traditional insulation, enabling a reduction in the footprint, size and structural costs of complex facilities. The flexible form factor of our products also makes them faster to install than rigid insulation materials, which reduces labor costs and total installed costs. In addition, our products reduce the volume and weight of material purchased, inventoried, transported and installed in the field, and they reduce the number of stock-keeping units required to complete a project. Simplified logistics accelerate project timelines, reduce installation costs and protect workers.

• High Durability and Fire Protection. Our aerogel blankets offer excellent compression resistance, tensile strength and vibration resiliency. Our products allow companies to pre-insulate, stack and transport steel pipes destined for use in harsh environments, which significantly reduces installation

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labor costs in remote areas. In addition, our Pyrogel XTF product was specifically designed to provide strong fire performance in applications within the energy infrastructure and other end markets.

When choosing products in the energy infrastructure market, we believe that end-use customers evaluate which insulation product enables them to meet their performance requirements with the lowest installed and/or lifecycle costs. We believe these product attributes uniquely address the demanding performance requirements of the energy infrastructure market. In particular, these attributes help our end-use customers reduce long-term operating and capital costs and meet their goals to enhance safety and reliability. We believe these characteristics are leading our end-use customers to choose our insulation products in a growing number of energy infrastructure facilities.

Substantially all of our product revenue has been, and we expect will continue to be over the next several years, derived from new construction, major capital expansion projects, and maintenance where our products are replacing traditional insulation materials. In the long-term, based on the maintenance schedules and needs of our end-users, we expect that there will be sales opportunities for us in connection with the replacement of our previously installed aerogel products.

Our Competitive Strengths

We believe the following combination of capabilities distinguishes us from our competitors and positions us to continue to gain market share in the energy infrastructure insulation market:

• Disruptive Products with a Compelling Value Proposition. Our aerogel products provide two to five times the thermal performance of widely used traditional insulation in a thin, easy-to-use and durable blanket form. We believe our array of product attributes provides strong competitive advantages over traditional insulation and will enable us to gain a larger share of the energy infrastructure insulation market. Although competing insulation materials may have one or more comparable attributes, we believe that no single insulation material currently available offers all of the properties of our aerogel insulation.

• Attractive Energy End Markets. Our products are primarily used in large scale energy infrastructure facilities. Freedonia has estimated that the worldwide energy infrastructure insulation market totaled $2.8 billion in 2013 and is expected to grow to $3.5 billion by 2018. Global energy demand for all forms of energy is expected to increase by 56% from 2010 to 2040, according to the International Energy Outlook 2013 report by the EIA. Given the continued growth in global energy consumption, and the construction of new facilities to satisfy this demand, we believe that we serve attractive and growing global end markets. In order to capture the opportunities in our end markets, we have a network of sales professionals and qualified distributors in more than 30 countries around the world.

• Growing Installed Base with Industry-leading End-Users. We have an installed base of more than 100 million square feet of insulation, representing more than $250 million in cumulative product sales since 2008. Through our relationships with industry leading end-use customers, our products have undergone rigorous testing and technical validation and are now in use at many of the world’s largest oil producers, refiners and petrochemical companies. These relationships have shortened the sales cycle with other customers and have helped to facilitate our market penetration. We also have strong relationships with a global network of energy-focused distributors, contractors and engineering firms that understands the significant advantages our products provide to end-users. We believe our products have been used by 24 of the world’s largest 25 refining companies and 19 of the world’s largest 20 petrochemical companies and have been initially deployed in approximately 30% of the world’s 640 refineries.

• Proven, Scalable Business Model. Our proprietary manufacturing technology is proven and has been successfully scaled up to meet increasing demand. We have operated the East Providence facility at high volume and high yield since 2008. We successfully commenced operation of our second production line

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at this facility in March 2011 and doubled our annual nameplate capacity to 40 million to 44 million square feet of aerogel blankets.

• Protected Technology Platform and Proprietary Manufacturing Capability. Our product solution is the result of more than a dozen years of research and development dedicated to new aerogel compositions, form factors and manufacturing technologies. Our intellectual property portfolio is supported by 51 issued patents, with an additional 18 pending in U.S. and foreign jurisdictions in areas related to product design, chemistry, process technology and market applications. In addition, we believe we have significant trade secrets related to product formulations and manufacturing techniques. We believe our portfolio of patents, trade secrets and know-how presents a formidable barrier to potential new entrants in the production of aerogel blanket insulation.

• Experienced Management Team with a Demonstrated Track Record. Our executive officers have an average of more than 20 years each of experience in global industrial companies, specialty chemical companies or related material science research. This management team is responsible for the development of our proprietary manufacturing technology, the commercial acceptance of our products, and the creation of a global distribution and marketing platform. As of April 15, 2014, we employed 220 research scientists, engineers, manufacturing line operators, sales and administrative staff, and management. We believe our dedicated and experienced team is an important competitive asset. Our senior management team and key employees will continue to have a significant equity stake in Aspen Aerogels following this offering.

Our Growth Strategy

Our strategy is to create shareholder value by becoming the leading provider of high-performance insulation products serving global energy infrastructure customers. Key elements of our strategy include:

• Expand Our Manufacturing Capacity to Meet Market Demand. Demand for our aerogel products has grown significantly. From 2008 through 2013, our product revenue has grown at a compound annual growth rate of 37% to $82.1 million. To meet anticipated growth in demand for our products, we are engaged in the design, engineering and procurement phases of a third production line in our East Providence facility and plan to construct a second manufacturing facility in Europe or Asia. We expect that this third production line at our East Providence facility will increase our annual nameplate capacity by 10 million to 11 million square feet of aerogel blankets at a total additional construction cost of approximately $30 million. We expect this third production line to be completed in the first half of 2015. We also intend to build a second production plant in Europe or Asia after completion of our third production line. We anticipate initial operation of the first production line at this facility during 2017. Based on our preliminary plans for this plant, our projected cost to construct this first production line and plant infrastructure for a multi-line facility is $80 million to $100 million with an estimated annual nameplate capacity of 26 million to 28 million square feet of aerogel blankets. The plant infrastructure design would also support future development of two additional similar production lines.

• Increase Our Market Share. We plan to focus additional resources to continue to grow our share of the energy infrastructure insulation market, both through increased sales to our existing customers and through sales to new customers. We will continue to expand our global sales force and distribution network in support of this objective and seek to promote greater enterprise-wide utilization of our products by existing end-use customers. To date, the majority of our revenue has been generated from applications in refineries and petrochemical facilities. We will continue to pursue and expect greater adoption of our products in the oil production, LNG production and storage, and power generation markets.

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• Exploit Project Growth Opportunities. Our product revenue has been and will be generated in large part by demand for insulation associated with scheduled plant shutdowns, or turnarounds, and other maintenance-related projects. With our broad adoption and growing installed base, we expect that our products will be specified during the design phase in a growing number of new plant construction and capital expansion projects. We expect that growth in global energy demand will result in increased new-build and large capacity expansion projects, driving demand for our aerogel products.

• Continue to Improve Our Profit Margins. We will continuously improve the cost efficiency of our manufacturing process to optimize the formulation of our products and to manage our supply chain to reduce costs. In addition, we plan to establish our second facility in a lower-cost labor market. As our overall manufacturing scale grows, we believe there will be additional opportunities to realize efficiencies and to reduce our per unit overhead costs. We believe our current expansion plan offers attractive returns on incremental invested capital.

• Capitalize on Innovation. We employ a team of research scientists and process engineers focused on advancing our current aerogel technology and developing next generation aerogel compositions, form factors and manufacturing processes. We believe that we are well positioned to leverage a decade’s worth of research and development to design and commercialize additional disruptive aerogel products for the energy infrastructure market. In addition, as we continue to enhance our technology and expand our capacity, we believe we will have opportunities to address additional high value applications in the estimated $37 billion global insulation market.

Our Products

Aerogels are complex structures in which 97% of the volume consists of air trapped between intertwined clusters of amorphous silica solids. Aerogels are a very low density solid and are usually extremely fragile materials. However, our proprietary manufacturing process produces aerogels in a flexible, resilient, durable and easy-to-use blanket form.

The core raw material in the production of our aerogel products is a silica-rich stream of ethanol. Our manufacturing process initially creates a semi-solid alcogel in which the silica structure is filled with ethanol. We produce aerogel by means of a supercritical extraction process that removes ethanol from the gel and replaces it with air. Our process allows the liquid ethanol to be extracted without causing the solid matrix in the gel to collapse from capillary forces.

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The composition of our aerogel products minimizes the three mechanisms of thermal transport:

• Conduction. Heat conduction through a material is correlated to the material’s density. Aerogels are very low density solids. As a result, thermal conductivity through the aerogel material itself is extremely low.

• Convection. Heat convection in gases is through movement of gas molecules. Due to the restricted movement of gases in the aerogel structure, thermal convection is eliminated inside the aerogels.

• Radiation. Radiation requires no medium to transfer the heat. Thermal radiation is partially absorbed by aerogels. Our aerogel products also contain infrared absorbing additives to significantly reduce radiant heat transfer.

We believe our aerogel products offer the lowest levels of thermal conductivity, or best insulating performance, of any widely used insulation available on the market today. Our aerogel blankets are reinforced with non-woven fiber batting. We manufacture and sell our blankets in 60 inch wide, three foot diameter rolls with a standard range of thickness of 5 millimeters to 10 millimeters. Our base products are all flexible, hydrophobic yet breathable, compression resistant and able to be cut with conventional cutting tools. We have specifically developed our line of aerogel blankets to meet the requirements of a broad set of applications within our target markets. The composition and attributes of our aerogel blankets are described below:

Energy Infrastructure Markets

• Pyrogel XT/XT-E. Pyrogel XT/XT-E, our best selling product, is reinforced with a glass-fiber batting and has an upper use temperature of 650^oC. Pyrogel XT was initially designed for use in high temperature systems in refineries and petrochemical facilities, and we believe that it has wide applicability throughout the energy infrastructure market. Pyrogel XT’s hydrophobicity and vapor permeability reduce the risk of corrosion under insulation in high temperature operating systems when compared to traditional insulation.

• Pyrogel XTF. Pyrogel XTF is similar in thermal performance to Pyrogel XT, but is reinforced with a glass- and silica-fiber batting. Pyrogel XTF is specially formulated to provide strong protection against fire.

• Cryogel Z. Cryogel Z is designed for sub-ambient and cryogenic applications in the energy infrastructure market. Cryogel Z is reinforced with a glass- and polyester-fiber batting and is produced with an integral vapor barrier. Cryogel Z is also specially formulated to minimize the incidence of stress corrosion cracking in stainless steel systems. We believe that Cryogel Z’s combination of properties allow for simplified designs and reduced installation costs in cold applications throughout the energy infrastructure market when compared to traditional insulation.

• Spaceloft Subsea. Spaceloft Subsea is reinforced with glass- and polyester-fiber batting and is designed for use in pipe-in-pipe applications in offshore oil production. Spaceloft Subsea can be fabricated and pre-packaged to permit faster installation. Spaceloft Subsea allows for small profile carrier pipelines and associated reductions in capital costs.

Other Markets

• Spaceloft. Spaceloft is reinforced with a glass/polyester fiber batting and is designed for use in the building and construction market. Spaceloft is either utilized in roll form by contractors in the field or fabricated by OEMs into strips, panels and systems that meet industry standards. Spaceloft is designed for use in solid wall buildings and where space is at a premium.

• Cryogel X201. Cryogel X201 is similar in composition to Cryogel Z, but is produced without a vapor barrier. Cryogel X201 is designed for use in cold system designs where space is at a premium. Cryogel X201 is targeted to OEMs that design, produce and sell refrigerated appliances, cold storage equipment and aerospace systems.

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The attributes of these aerogel blankets are summarized in the following table:

Product	Nominal Thickness				Thermal Conductivity*				Density				Maximum Use Temperature				Applications	Markets
	mm		in		mW/ m-K		Btu**-in/ hr-ft2-°F		g/cc		lb/ft3		°C		°F
Pyrogel XT/ XT-E		5.0		0.20		21.0		0.15		0.20		12.5		650		1202	High temperature steam	Energy
ASTM C1728 compliant		10.0		0.40													pipes, vessels & equipment; aerospace & defense systems	Infrastructure
Pyrogel XTF		10.0		0.40		21.0		0.15		0.20		12.5		650		1202	High temperature steam pipes, vessels & equipment; aerospace & defense systems; fire barriers; welding blankets	Energy Infrastructure
Cryogel Z		5.0		0.20		17.0		0.12		0.16		10.0		125		257	Sub-ambient & cryogenic	Energy
ASTM C1728 compliant		10.0		0.40													pipelines, vessels & equipment	Infrastructure
Spaceloft Subsea		5.0 10.0		0.20 0.40		14.5		0.10		0.16		10.0		200		390	Medium to high temperature offshore oil pipelines	Energy Infrastructure
Spaceloft		5.0		0.20		16.5		0.12		0.16		10.0		200		390	Ambient temperature walls,	Other Markets
		10.0		0.40													floors & roofs in commercial, residential & institutional buildings
Cryogel x201		5.0		0.20		17.0		0.12		0.16		10.0		200		390	Sub-ambient including	Other Markets
		10.0		0.40													refrigerated appliances, cold storage & aerospace

* Thermal conductivity at 37.5° C, 2 psi compressive load and standard atmospheric pressure.

** “Btu” means one British thermal unit, the quantity of heat required to raise the temperature of a one-pound mass of water by one degree of Fahrenheit.

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R-Values by Material

Insulation is a material or combination of materials that slows the transfer of heat from one side of the insulation material to the other. The lower a material’s thermal conductivity, the more slowly heat is transferred across it. R-values are a commonly used measure of an insulating material’s resistance to heat transfer. R-value is calculated as the thickness of an insulation material divided by the thermal conductivity of the insulation material. Materials with higher R-values have lower thermal conductivity and are better insulators. Traditional and specialty insulation materials provide a range of R-values. The following table provides the R-value per meter of thickness of aerogels and traditional insulation materials:

		R-Value per meter of thickness
Material	Form	From		To
Aerogel	Blankets, Beads		66		100
Cellulose	Loose Fill		22		26
Expanded Clay	Loose Fill		4		4
Expanded Polystyrene (EPS)	Boardstock		26		31
Extruded Polystyrene (XPS)	Boardstock		35		40
Fiberglass	Blankets		22		28
Fiberglass	Loose Fill		20		20
Fiberglass	Pipe Covering		25		25
Foamed Glass	Boardstock		21		21
Mineral Wool	Blankets		22		26
Mineral Wool	Loose Fill		17		17
Mineral Wool	Pipe Covering		19		26
Perlite	Pipe Covering		17		17
Perlite	Loose Fill		17		21
Perlite	Board		17		19
Polyurethane	Spray On		44		44
Polyurethane	Rigid Board		44		44
Polyisocyanurate	Rigid Board		45		50
Vermiculite	Loose Fill		17		26

Qualification for Use

Our products have undergone rigorous testing and are now qualified for global usage in both routine maintenance and in capital projects at many of the world’s largest oil producers, refiners and petrochemical companies as ranked by a weighted measure of sales, profits, assets and market value. These end-users of our products have well defined practices, codes, specification and standards for materials and systems installed or used in their facilities. These specifications include insulation system design standards, material qualification and selection processes, and insulation application practices. As part of the material qualification process run by these companies, a new insulation must meet general industry standards, such as consensus standards developed by ASTM International, and, in some cases, company-specific internal standards to be considered for use. In addition, most of these companies require one or more field trials to establish fitness for use in specific applications. The companies either run these qualification processes and field trials internally or through third parties engaged by them, and they generally do not publicly disclose the results of their testing. While the specific processes and timelines vary from company to company, in general, upon successful completion of the qualification process for an insulation material, an end-user will typically deem the material to be qualified for use in its facilities on a local, regional or global basis for one or more applications. Because our end-use customers are typically businesses with very large operations, our insulation sales likely represent only a small portion of the total insulation used by any one of these companies. Accordingly, once our products are qualified at a company, we continue to seek to expand use of our products by the end-use customer.

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Sales and Marketing

We market and sell our products primarily through our sales force. Our salespeople are based in North America, Europe and Asia and travel extensively to market and sell to new and existing customers. The efforts of our sales force are supported by a small number of sales consultants with extensive knowledge of a particular market or region. Our sales force is required to establish and maintain customer and partner relationships, to deliver highly technical information and to provide first class customer service. We have plans to expand our sales force globally to support anticipated growth in customers and demand for our products.

Our sales force calls on and maintains relationships with all participants in the insulation industry supply chain. Our salespeople have established and manage a network of insulation distributors to ensure rapid delivery of our products in critical regions. Our salespeople work to educate insulation contractors about the technical and operating cost advantages of aerogel blankets. Our sales force works with end-users and engineering firms to promote qualification, specification and acceptance of our products. In the energy infrastructure market, we rely heavily on the existing and well-established channel of distributors and contractors to deliver products to our customers. In addition, our salespeople work with OEMs and development partners to create new products and solutions to expand our market reach.

The sales cycle for a new insulation material is typically lengthy. Our sales cycle from initial customer trials to widespread use can take from one to three years, although we typically realize increasing revenue at each stage in the cycle. Our relationships with technically sophisticated customers serve to validate our technology, products and value proposition within a target market. These relationships have proven to shorten the sales cycle with other customers within specific market segments and to facilitate market share growth. We have focused our marketing efforts on developing technical support materials, installation guides, case studies and general awareness of the superior performance of our aerogel blankets. We rely on our website, printed technical materials, participation in industry conferences and tradeshows and presentation of technical papers to communicate our message to potential customers. We also receive strong word-of-mouth support from the growing network of distributors, contractors, OEMs and end-users that understand the benefits of our products.

As of April 15, 2014, we had 28 employees in our sales and marketing organization worldwide. Their efforts were supported by a team of seven sales consultants.

Customers and End-Users

Customers

As described below, our primary customers are distributors, contractors and OEMs that stock, install and fabricate insulation products, components and systems for technically sophisticated end-users that require high-performance insulation.

• Distributors: We currently operate through a global network of over 40 insulation distributors. In general, insulation distributors stock, sell and distribute aerogel materials to insulation contractors and end-users. The distribution of our product outside the United States is typically conducted under agreements that provide for exclusivity by geography linked to annual purchase volume minimums. These insulation distributors often will also proactively market and promote aerogel materials across their market. During 2013, our top distributors by revenue were Distribution International in the United States, Alltech Consulting in Asia and NewStar Solutions in Canada.

• Contractors: We currently sell directly to a number of insulation contractors under project specific contracts or general purchase orders. Insulation contractors generally perform insulation installation, inspection and maintenance and project management for end-users. In addition, some insulation contractors provide end-users with project engineering and design services. Several of our agreements with contractors provide for exclusivity by market sector or geography linked to annual purchase volume minimums. During 2013, our top contractor customers by revenue included Technip in the global offshore market, Industrial Services in the Asian refinery market and Insultec in the Asian gas processing market.

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• OEMs: We currently sell directly to more than ten OEMs that design, fabricate and manufacture insulation components and systems for use in the energy infrastructure, other industrial, building and construction, transportation, appliance and apparel markets. During 2013, our top OEM customers by revenue were Stadur Produktions for wall systems, SMC Industries for aerogel accessories and Shenzhen Hochuen Special Packing Product Company for fabricated parts used in trains.

• Direct Sales to End-Users: In certain instances, we sell directly to end-use customers in the energy infrastructure insulation market. During 2013, our top direct end-use customers in this market by revenue were a major Asian energy company and Genesis Solar, a NextEra Energy Resources project.

Distribution International and Alltech Consulting represented 15% and 11%, respectively, of our total revenue for 2013 and were our only customers representing 10% or more of our revenue for that period.

Our product revenue is generated by sales to customers around the world. In 2013, our product revenue, based on our shipment destination, was comprised of 32% in the United States, 32% in Asia-Pacific, 18% in Europe, 10% in Canada and 8% in Latin America.

End-Users

As described below, the end-users of our aerogel blankets include some of the largest and most well capitalized companies in the world. Our products are installed in more than 40 countries worldwide.

Energy Infrastructure

• Oil Refining: We believe we have had initial product deployments in approximately 30% of the world’s 640 refineries. In addition, we believe our aerogel blankets are used by 24 of the world’s 25 largest refining companies including ExxonMobil, Petrobras and Chevron, among others. We believe these companies are the largest purchasers of our products by revenue during 2013 across the oil refinery market. Over time, these companies have used our products in an increasing range of applications and throughout an increasing number of their facilities.

• Petrochemical: We believe our aerogel blankets are used by 19 of the world’s 20 largest petrochemical companies including Formosa Petrochemical, Hu-Chems Company and a major Asian energy company, among others. We believe these companies are the largest purchasers of our products by revenue during 2013 across the petrochemical market.

• Natural Gas and LNG: Our products are in use at ExxonMobil, Pemex Gas and Qatargas, among others. We believe these companies are the largest purchasers of our products by revenue during 2013 for use in natural gas and LNG facilities.

• Onshore: Our aerogel blankets are in use in several Canadian oil sands facilities owned and operated by Suncor Energy, ConocoPhillips and Husky Energy, among others. We believe these companies are the largest purchasers of our products by revenue during 2013 for use in oil sands facilities.

• Offshore: Our products are currently used in subsea projects off the coast of Brazil, in the Gulf of Mexico, in the North Sea, off the coast of Malaysia and off the west coast of Africa. Our products are installed in offshore projects owned by Marathon Oil, ConocoPhillips and Shell, among others. We believe these companies are the largest end-users of our products by revenue in the offshore market during 2013.

• Power Generation: We are targeting operators of gas, coal, nuclear, hydro and solar power generating facilities. Although not a significant portion of our revenue today, our products are currently used, among others, at a facility owned and operated by NextEra Energy Resources. We believe that NextEra Energy Resources was the largest purchaser of our products by revenue during 2013 for use in power generation facilities.

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Other Markets

We rely on the efforts of a small network of OEMs and fabrication houses to serve the building and construction, transportation, apparel and appliance markets. Our OEMs and fabricators are manufacturers of components and systems for buildings, refrigerated and hot appliances, cold storage equipment, automobiles, aircraft, trains and electronic sectors and manufacturers of outdoor gear and apparel. While our products have not yet been widely adopted in these markets, we expect that the end-users of our products in these markets will include a wide range of institutions, businesses, individuals, and government agencies.

Customer Case Studies

The following case studies illustrate how our customers and end-users benefit from our industry leading thermal performance and unique set of performance attributes:

• Oil Refining: A delayed coker unit at a Texas refinery of a global energy company was energy constrained. Its furnaces could not keep up with the rate of heat loss through the existing mineral wool insulation which caused the coke drums to operate below the targeted temperature, resulting in sub-optimal product yields. When two new coke drums were installed, a better insulation solution was sought. Insulating drums with Pyrogel XT allowed this end-use customer to reach higher peak temperatures which enabled better conversion efficiency. The cost to insulate these two drums in Pyrogel was $150,000, and they generated an additional $3 million of salable coke in the first year after the installation. This end-use customer has indicated that it intends to use Pyrogel to insulate four more drums at this refinery, plus four more in an Illinois refinery, with several more in the design phase. After our initial installation in 2010, our insulation has been used to insulate 34 drums around the world through 2013. We estimate that there are more than 500 coke drums in service globally.

• Petrochemical: Formosa Petrochemical was facing severe corrosion under insulation (CUI) challenges at their petrochemical complex in Mailiao, Taiwan. In 2011, they embarked on a facility-wide renewal project, including a commitment to achieve world-class levels of corrosion control. As part of that commitment, Formosa specified the use of Pyrogel XT in a wide-range of applications, including on a massive new pipe rack running through its facility. The thinner insulation allowed them to pack their piping more tightly, reducing the number of pipe decks from three to two, and freeing additional space for future expansion work.

• Natural Gas and LNG: A global energy company was experiencing difficulty insulating certain components of an LNG import terminal in Europe. The LNG import terminal contained cellular glass valve boxes that needed to be insulated with material that had both (i) a thin profile in order to address space constraints and (ii) durability and ease of installation to permit pre-installation onshore and transportation to a harsh offshore environment. In addition, the level of fire-resistance required for a facility of this type precluded the use of the traditional organic foams such as polyurethane. Our Cryogel Z blankets designed for cold applications provided compact design, durability and fire protection, three important selection criteria for this project. Since this installation in 2008, Cryogel has been installed in more than two dozen LNG import, export and storage facilities, providing an unmatched combination of thinness and fire protection.

• Onshore: A major oil and gas company was seeking to reduce the cost of installing insulation for its oil sands project in Alberta, Canada. During construction of the first phase of this oil sands project, the company insulated its steam distribution piping after they had been delivered to the remote project location which required setting up facilities to house the insulation workers and transporting supports, piping and insulation to the project location. In addition, pipes had to be installed sequentially in the field under harsh weather conditions. When the company designed the second phase of this project, it sought to reduce its installation costs and chose Pyrogel XT-E. Because Pyrogel XT-E is highly durable, this end-use customer was able to pre-insulate its steam distribution piping offsite in a climate controlled facility before transporting the piping to the project site, resulting in a reduction of more than 50% in labor costs and allowing for faster installation.

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Manufacturing

We manufacture our products using our proprietary technology at our facility located in East Providence, Rhode Island. We have operated the East Providence facility at a high volume and high yield since 2008. Our manufacturing process is proven and has been scaled up to help meet increasing demand.

Our manufacturing group is led by a seasoned team with management experience at global industrial and specialty chemical companies. Our manufacturing workforce is experienced and, to date, we have experienced employee turnover consistent with others in our industry. We have well-defined maintenance and environmental, health and safety programs and operating processes in place. We utilize statistical process and quality controls to measure the thermal conductivity, hydrophobicity and thickness of our aerogel blankets during the manufacturing process. We are ISO 9000:2000 certified.

We price our product and measure our product shipments in square feet. We successfully commenced operation of our second production line at this facility at the end of March 2011, which doubled our annual nameplate capacity to 40 million to 44 million square feet of aerogel blankets, depending on product mix. We are in the design and engineering phase of a third production line and have procured certain capital equipment with a longer lead-time. We currently expect that this third line will increase our current capacity by 25% to 50 million to 55 million square feet and will be completed during the first half of 2015. We plan to construct a second manufacturing facility in Europe or Asia, the location of which will be based on factors including labor and construction costs, availability of governmental incentives and proximity to material suppliers. We anticipate initial operation of a first production line at this facility during 2017.

The chart below illustrates our historical production and nameplate and effective capacities, which will be critical to our revenue growth in the coming years. Nameplate capacity represents our projected maximum sustainable annual output. As we add capacity, we ramp up our production over time towards our nameplate capacity. Our effective capacity is the capacity at which we believe we can operate while maintaining the quality of our products and efficiency of our operations in a given period. Actual effective capacity is also impacted by the date within a given year on which we add the capacity. The projected nameplate and effective capacity for the years 2014 through 2018 are based on certain assumptions that our management believes are reasonable, but these assumptions could prove to be incorrect, which could result in our actual capacity differing materially from the projections below. See “Risk Factors — Risks Related to Our Business and Strategy — If we fail to achieve the increase in production capacity that our continued growth requires in a timely manner, or at all, our growth may be hindered and our business or results of operations may be materially adversely affected.”

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We directly control all stages in the manufacture of our aerogel blankets. Our direct ownership of manufacturing operations allows us to maintain control of proprietary process technologies and to control product quality. Our production of aerogel blankets utilizes a continuous batch process and consists of the following key steps:

• Sol Preparation. Mixing of a silica precursor in ethanol, a catalyst and additives in set formulas to deliver the target properties of the resultant aerogel.

• Casting. Application of the sol into a non-woven batting and initial formation of the gel structure.

• Aging. Bathing of the gel-saturated blankets in fluids to impart desired physical and thermal properties.

• Extraction. Supercritical extraction of the ethanol liquid from the gel-saturated blanket to produce an aerogel blanket.

• Heat Treatment. Drying to remove trace ethanol, ammonia salts and water from the aerogel blankets.

• Finishing. Coating to enhance quality and product handling.

• Quality Control. Utilizing statistical process and quality controls to measure thermal conductivity, hydrophobicity and thickness of our aerogel blankets.

Our material costs were the equivalent of 53%, 61% and 47% of product revenue for the years ended December 31, 2011, 2012 and 2013, respectively. The materials used in the production of our products consist primarily of polyester and fiberglass battings, amorphous silica and ethanol, which is used in the delivery of the amorphous silica. Multiple sources of supply exist for all of our materials, and we believe the markets for these products are competitive and prices are relatively stable. We purchase amorphous silica from several suppliers. Based on the current level of demand for our products, we believe that an adequate long-term supply of amorphous silica is available. However, if demand for our products increases rapidly, we will need to work with suppliers to ensure that an adequate long-term supply of amorphous silica will be available. Suppliers of amorphous silica include industrial companies that produce it directly or that produce it as a byproduct of other industrial processes. We are working with a number of suppliers to plan for our potential future needs and to develop processes to reduce the long-term cost of the amorphous silica used in our products. See “Risk Factors — Risks Related to Our Business and Strategy — Shortages of the raw materials used in the production of our products, increases in the cost of such materials or disruptions in our supply chain could adversely impact our financial condition and results of operations.”

We are seeking to lower our manufacturing costs and to improve the per square foot costs of our aerogel blankets by optimizing our chemistries and manufacturing processes to improve yields, by obtaining material price reductions from existing vendors, by qualifying new vendors for certain materials and by optimizing shipping costs. Our objective is both to reduce costs to enhance our competitive advantage and to ensure we deliver high quality finished products.

Research and Development

The mission of our research and development team is to leverage innovation in support of our commercial objectives, including by designing additional disruptive products for the energy infrastructure market and seeking methods to lower our manufacturing costs and to improve yields. Our research and development expenditures were $4.1 million, $5.1 million and $5.2 million for the years ended December 31, 2011, 2012 and 2013, respectively. In addition, we spent $1.5 million, $1.4 million and $2.0 million for the years ended December 31, 2011, 2012 and 2013, respectively, on research and development activities sponsored by federal and non-federal government agencies. Our scientists and engineers work closely with customers to study and assess insulation application requirements and guide advancements in aerogel materials and manufacturing. The scope and focus of our research and development activities include:

• Research: Our research scientists and process engineers explore various chemistries and process technologies to enhance product performance in response to needs for high temperature thermal

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stability, high compression strength, corrosion resistance, low density, low thermal conductivity at low, ambient and high temperatures, high resilience and flexibility and resistance to environmental elements. Our research scientists are investigating various aerogel compositions beyond the fiber reinforced silicate aerogel materials which are the backbone of current products. Carbon, ceramic, rubber and hybrid aerogels are all topics of study. A range of form factors are under exploration, including flexible sheets, monoliths, beads and powders.

• Development: Our development team responds to customer needs for new and broader performance aerogel products. Our efforts to enhance the aerogel product line currently include new grades of flexible aerogels with higher temperature performance, compression resistance, flame and smoke resistance and improved low infrared signature properties.

• Analytical Services: We have invested in testing and characterization equipment for chemical, mechanical and thermal property measurements. The instrumentation allows in-house measurement of all key properties related to formulation and performance of aerogel products. The analytical laboratory is managed on a service basis with testing prioritized against commercial opportunities. We supplement our in-house capabilities with third party laboratory services.

• Process Engineering: We maintain a range of pilot equipment that allows rapid examination of formulation and process variables at the research scale. This capability allows the study and continuous improvement of operating processes and provides the ability to produce a range of novel product forms.

• Program Management: We have a demonstrated record of success in winning and delivering upon government research programs. Research and development performed under contract to NASA, NSF, DARPA, U.S. Army, U.S. Navy, U.S. Air Force and the Department of Energy enables us to develop and leverage technologies into broader commercial applications.

• Business Development and Technology Transition: We work closely with customers in government and industry to develop potential aerogel solutions that leverage a wide range of attributes of aerogels. We have a long history and demonstrated capability of successfully transitioning technologies from the lab scale into full production.

We believe that we are well positioned to leverage a decade’s worth of research and development activity to continue to commercialize additional disruptive products, applications and advanced manufacturing technologies for the energy infrastructure market. We have already obtained patents for a number of these technologies in the United States and abroad. We also maintain a portfolio of trade secrets and know-how in areas of gel compositions and aerogel manufacturing. As of April 15, 2014, we employed 19 research and development employees and eight manufacturing engineers.

Contract Research and Government Support

We have a demonstrated record of pursuing and securing government support for our business:

• Contract Research. We regularly seek funding from a number of federal and non-federal government agencies in support of our research and development and manufacturing activities. Research performed under contract to NASA, National Science Foundation, Defense Advanced Research Projects Agency, U.S. Army, U.S. Navy, U.S. Air Force and the Department of Energy allows us to develop and leverage technologies into broader commercial applications. We also work closely with customers in government and industry to develop potential aerogel solutions that leverage not only the thermal insulation performance but other benefits of aerogels as well. The research and development activities that we conduct under such contracts may produce intellectual property to which we may not have ownership or exclusive rights and will be unable to protect or monetize.

Under our contracts, the U.S. government generally has the right not to exercise options to extend or expand our contracts and may modify, curtail or terminate the contracts at its convenience. Our

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government customers may not renew our existing contracts after the conclusion of their terms and we may not be able to enter into new contracts with U.S. government agencies. Any decision by the U.S. government not to exercise contract options or to modify, curtail or terminate our contracts or not to renew our contracts or enter into new contracts with us would adversely affect our revenues.

We have received $44.3 million in funding under contracts since inception through December 31, 2013. Our contract research revenue was $3.2 million, $3.1 million and $4.0 million for the fiscal years ended December 31, 2011, 2012 and 2013, respectively.

• Title III. Title III of the Defense Production Act was established to create, expand and maintain domestic capacity to produce materials needed for national defense. Title III has accelerated technology adoption by establishing competitive and reliable U.S. sources for key materials. We have received $16.8 million in awards under Title III to build our first production line in East Providence, Rhode Island, to expand effective nameplate capacity and to reduce manufacturing costs of high temperature aerogel blankets.

• Rhode Island. Our East Providence facility is located in a Rhode Island Enterprise Zone. We have received job training grants/credits from the State of Rhode Island.

Intellectual Property

Our success depends in part upon our ability to obtain, maintain and protect intellectual property rights that cover our product forms, applications and/or manufacturing technologies and specifications and the technology or know-how that enables these product forms, applications, technologies and specifications, to avoid and defend against claims that we infringe the intellectual property rights of others, and to prevent the unauthorized use of our intellectual property. Since aerogels were developed approximately 80 years ago, there has been a wide range of research, development and publication on aerogels, which makes it difficult to establish intellectual property rights to many key elements of aerogel technology and to obtain patent protection. Where we consider it appropriate, our policy is to seek to protect our proprietary rights by filing United States and foreign patent applications related to technology, inventions and improvements that we consider patentable and important to the development and conduct of our business and, in particular, our aerogel technology, product forms and their applications in promising markets and our manufacturing technologies. Patents owned by us that we consider important to our business include: U.S. Patent Nos. 7,078,359 and 7,504,346, as well as related foreign counterparts which are directed to fiber-reinforced aerogel composites and expire on December 21, 2021; U.S. Patent No. 7,226,243, which is directed to sub-sea pipeline systems incorporating our aerogel blankets and expires on May 5, 2024; U.S. Patent Nos. 7,399,439, 6,989,123 and 7,780,890, as well as related foreign counterparts, all of which are directed to methods of manufacturing fiber-reinforced aerogel composites and expire on June 23, 2024; U.S. Patent No. 7,560,062, which is directed to methods of fabricating high-strength fiber-reinforced nanoporous bodies and expires on July 12, 2025; U.S. Patent No. 7,833,916, which is directed to aerogel-based building materials and expires on July 18, 2025; U.S. Patent No. 8,461,223, which is directed to mechanically strong organic aerogels and composites and expires on April 6, 2026; and U.S. Patent No. 7,691,912, which is directed to organic/inorganic hybrid aerogel composites and expires on October 10, 2027; and U.S. Patent No. 8,214,980, which is directed to fabrication of aerogel blankets and expires on January 11, 2030. We also rely on trade secrets, trademarks, licensing agreements, confidentiality and nondisclosure agreements and continuing technological innovation to safeguard our intellectual property rights and develop and maintain our competitive advantage.

As of April 15, 2014, we had 21 issued U.S. patents, 13 pending U.S. patent applications (including two U.S. patents that we co-own with third parties), 30 issued foreign patents and five pending foreign patent applications (including one European patent and a family of pending patent applications that we co-own with a third party). The U.S. patents that we own are generally effective for 20 years from the filing date of the earliest application to which each U.S. patent claims priority. The scope and duration of each of our foreign patents varies in accordance with local law. Our ability to maintain and solidify both our proprietary and our licensed

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technology will depend in part upon our success in obtaining patent rights and enforcing those rights once granted or licensed in appropriate jurisdictions. We do not know whether any of our patent applications or those patent applications that we license from others will result in the issuance of any patents. Our issued patents and those that may issue in the future, or those licensed to us, may be challenged, invalidated, rendered unenforceable or Moreover, enforcement of our patent rights may be complicated in some foreign jurisdictions due to lack of effective enforcement tools. In addition, the rights granted under any issued patents may not provide us with competitive advantages against competitors. Furthermore, our competitors may independently develop similar technologies or duplicate technology developed by us or may possess intellectual property rights that could limit our ability to manufacture our products and operate our business, particularly given the long history of the circumvented, which could limit our ability to prevent competitors from marketing similar or related products, or shorten the term of patent protection that we may have for our products, technologies and enabling technologies. development of aerogel technology. Because of the extensive time required for research, development and testing of a potential product, it is possible that, before a product under development can be commercialized, any related patent, whether owned by us or licensed to us, may expire or remain in force for only a short period of time following commercialization, thereby substantially reducing or eliminating any advantage of the patent.

We also rely on trade secret protection for our proprietary technology. However, trade secrets can be difficult to protect. We may not be able to maintain our technology or know-how as trade secrets, and competitors may develop or acquire equally valuable or more valuable technology or know-how related to the manufacture of comparable products. We also seek to protect our confidential and proprietary information, in part, by requiring employees and consultants to execute confidentiality and/or nondisclosure agreements upon the commencement of an employment or consulting arrangement with us. These agreements generally require that all confidential and proprietary information developed by the individual or made known to the individual by us during the course of the individual’s relationship with us be kept confidential and not disclosed to third parties. These agreements may be breached and may not provide adequate remedies in the event of breach. We also require our customers and vendors to execute confidentiality and/or nondisclosure agreements. However, we have not obtained such agreements from all of our customers and vendors. Moreover, some of our customers may be subject to laws and regulations that require them to disclose information that we would otherwise seek to keep confidential. In addition, our trade secrets may otherwise become known or be independently discovered by competitors, customers or vendors. To the extent that our employees, consultants, vendors or contractors use intellectual property owned by others in their work for us, disputes may arise as to the rights in related or resulting technologies, know-how or inventions.

We believe that having distinctive names may be an important factor in marketing our products, and therefore we use trademarks to brand some of our products, including Pyrogel, Cryogel and Spaceloft. As of April 15, 2014, we had five trademark registrations and one pending trademark application in the United States, 34 trademark registrations and 10 pending applications in other foreign jurisdictions, including the European Union, Japan, China, Canada, South Korea and Brazil. Although we have a foreign trademark registration program for selected marks, our approach may not be comprehensive enough or we may not be able to register or use such marks in each foreign country in which we seek registration.

We regularly seek funding from a number of federal and non-federal government agencies in support of our research and development and manufacturing activities. The research and development activities that we conduct under such contracts may produce intellectual property to which we may not have ownership or exclusive rights and will be unable to protect or monetize.

Cross License Agreement with Cabot Corporation

In April 2006, we entered into a cross license agreement with Cabot Corporation, or Cabot, which was amended in September 2007. Under the terms of the cross license agreement, each party has granted certain intellectual property rights to the other. The cross license agreement remains in effect until the expiration of the last to expire of the issued patents or patent applications and acquired patents licensed thereunder. We hold a

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non-exclusive, worldwide license to those patents and patent applications owned or licensed by Cabot that are necessary for us to (1) practice our manufacturing technology within a field of use, which is defined in accordance with the specific chemistry of our aerogel products and the supercritical fluid technology that we use in our manufacturing technology and (2) use and sell the resulting aerogel blanket and derivative products. We paid Cabot in full for this license, by paying $38 million over a period of approximately seven years, with the last payment made in March 2013. We have granted to Cabot a reciprocal, non-exclusive, worldwide license to certain patents and patent applications that we own that are necessary for Cabot to practice its processes within a field of use defined in accordance with the specific chemistry in its aerogel products and the drying technology that it uses to manufacture its products. The grant of license to each party covers issued patents, patent applications and patents issued from such counterpart applications, as well as patents licensed or acquired during a specified term, in each case that claim aerogels, or methods, materials of manufacture, or uses of aerogels.

If we intend to sell, transfer, pledge or mortgage any of the patent rights that we license to Cabot, such sale, transfer, pledge or mortgage is subject to the licenses granted to Cabot under the cross license agreement. We also bear full responsibility and liability for any loss, damage, personal injury or death resulting from, arising out of or connected with our use of the licensed Cabot intellectual property or our use or any third party’s use of any products manufactured using the licensed Cabot intellectual property. The right to assert infringement of one or more patents licensed under the cross license agreement resides solely with the patent owner and, thus, Cabot has the exclusive right, but not the obligation, to enforce its rights in its intellectual property licensed to us under the agreement at its own expense, and any decision as to whether or not to do so by Cabot must be accepted as final by us.

Competition

We operate in a highly competitive environment. In general, we compete with traditional insulation materials based on product performance, price, availability and proximity to the customer. Customers may choose among a variety of traditional insulation materials that offer a range of characteristics including thermal performance, durability, vapor permeability, moisture resistance, ease of installation and upfront and lifecycle costs. Within each type of insulation material, there is also competition between the manufacturers of that material. Most types of traditional insulation materials are produced by a number of different manufactures and once customers have chosen the type of insulation material that they intend to use, they will choose a manufacturer of that material based primarily on each manufacturer’s price and delivery schedule. Insulation manufacturers include a range of large, high-volume, multinational manufacturers offering branded products and strong technical support services to small, low-volume, local manufacturers offering low prices and limited customer support.

We believe the primary competitive factors in our market are:

• product performance (along multiple criteria), quality and fitness for purpose;

• product price, installed cost and lifecycle cost;

• product availability; and

• proximity to customer and logistics.

Our products are priced at a premium to traditional insulation materials. While our competitors offer many traditional insulation products that are priced below our products on a per-unit basis, our products have superior performance attributes and have the lowest cost on a fully-installed basis or offer significant life-cycle cost savings.

According to The Freedonia Group, industry leading manufacturers for each of the principal traditional insulation materials include:

• Foamed Plastics. Armacell, BASF, Bayer, Bridgestone, Dow Chemical, Johns Manville, Kingspan, Knauf Gips, Owens Corning, Recticel, Saint-Gobain, swisspor Management and Uralita.

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• Fiberglass. CSR, Fletcher Building, Johns Manville, Knauf Gips, Owens Corning, Saint-Gobain and Uralita.

• Mineral Wool. CSR, Johns Manville, Knauf Gips, Owens Corning, Paroc Group, Rockwool, Saint-Gobain and swisspor Management.

• Other. Manufacturers of foamed glass, calcium silicate, perlite and vermiculite tend to be limited to medium-sized, global or small-sized, regional suppliers.

We also compete in the aerogel insulation market with Cabot predominantly in the off-shore segment. In addition, we are aware of competitors in China that manufacture and market aerogel insulation products.

Within each of our target markets, we encounter these organizations and a significant number of other aggressive national, regional and local suppliers. Our competitors are both seeking to enhance traditional insulation materials and develop and introduce new and emerging insulation technologies. Competing technologies that outperform our insulation in one or more performance attributes could be developed and successfully introduced. We are aware of certain companies in Asia that are marketing aerogel products similar to our aerogel products over the Internet but we are not aware of any sales of their products in our targeted geographic markets. See “Risk Factors — Risks Related to Our Business and Strategy — The energy infrastructure insulation market is highly competitive; if we are unable to compete successfully, we may not be able to increase or maintain our market share and revenues.”

Our market share in 2013 was less than three percent of the estimated $2.8 billion annual global market for energy infrastructure insulation materials. Many of our competitors have greater market presence, larger market share, longer operating histories, stronger name recognition, larger customer bases and significantly greater financial, technical, sales and marketing, manufacturing and other resources than we have and may be better able to withstand volatility within the industry and throughout the economy as a whole while retaining greater operating and financial flexibility. If our competitors lower their prices, develop new products or if we are unable to compete effectively, our growth opportunities, share of the market, margins and profitability may decline.

Insulation Materials

The insulation materials that are currently most widely in use in the $37 billion insulation market are:

• Mineral Wool. First introduced in 1871, mineral wool is commonly used for insulation and fire protection in the building and construction market and in high temperature applications in the energy infrastructure market. The two different types of mineral wool are rock wool, which is produced from natural minerals, and slag wool, which is produced from iron ore blast furnace slag. Mineral wool is inexpensive, performs well at high temperatures and meets fire safety standards in the building and construction market, primarily in Europe.

• Foamed Plastics. Commercialized during the 1950s, foamed plastics are the most prevalent form of insulation material in the world and are used broadly in the appliance, transportation, industrial and building and construction markets. Foamed plastic insulation is made from inexpensive materials and is a cost-effective solution for many end-users. Foamed plastics provide some of the characteristics of solid insulation and are available in a wide variety of form factors. However, foamed plastics are generally not fire resistant.

• Specialty Materials. Other insulation materials are typically used in specialty applications. Generally, these insulations are either inexpensive, low performance materials or expensive, high-performance materials. Perlite and vermiculite are low performance materials used generally as lightweight, noncombustible insulation. Developed in the 1970s, calcium silicate was first used as a high-performance alternative that can be molded for retrofit industrial applications and can withstand high temperatures. Foamed glass is a high-performance, closed cell, lightweight material that has been used

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since the 1940s in industrial applications where chemical absorption is an issue. Vacuum insulated panels are a relatively new product that provides excellent thermal performance.

• Fiberglass. Developed and commercialized during the 1930s, fiberglass is used primarily in building and construction and transportation markets in North America. Fiberglass insulation is made of fine fibers of glass and is typically adhered with a chemical binder to a batt form. Fiberglass will not burn, but will melt under intensive heat. Fiberglass is inexpensive, easy to install, can be cut very easily and is primarily used to fill cavity spaces in building and construction applications.

The insulation materials that are most widely used in the energy infrastructure market are mineral wool, foamed plastics, calcium silicate, perlite, foamed glass and aerogel. Foamed plastics, fiberglass and mineral wool materials account for more than 96% of worldwide insulation demand. The remaining 4% of the market is comprised of specialty materials including aerogels, perlite, calcium silicate, foamed glass and vacuum insulated panels.

Employees

As of April 15, 2014, we had 220 full-time employees and no part-time employees, with 29 in research and development, 143 in manufacturing operations and supply chain, 28 in sales and marketing and 20 in general and administrative functions. Of our employees, 212 are located in the United States and 8 are abroad. We consider our current relationship with our employees to be good. None of our employees are represented by labor unions or have collective bargaining agreements.

Legal Proceedings

In the ordinary course of our business we may be party to various legal proceedings, including but not limited to those brought by our current or former employees, customers, suppliers and competitors, the outcome of which cannot be predicted with certainty. We are not involved in any legal proceedings that are expected to have a material adverse effect on our business, results of operations or financial condition. To the knowledge of our management, no legal proceedings of a material nature involving us are pending or threatened by any individuals, entities or governmental authorities.

Facilities

Our corporate headquarters are located in Northborough, Massachusetts, where we occupy approximately 83,000 square feet under a lease expiring on December 31, 2016. We also own an approximately 143,000 square foot manufacturing facility in East Providence, Rhode Island. In addition, we lease a 24,000 square foot facility and a 128,000 square foot facility both located in East Providence, Rhode Island, which leases expire on February 29, 2016 and March 31, 2019, respectively. We intend to construct a second manufacturing facility located in either Europe or Asia.

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MANAGEMENT

Executive Officers and Directors

Our executive officers, directors, director-elect and their respective ages and positions as of April 15, 2014 are as follows:

Name	Age		Position
Executive Officers
Donald R. Young		56	President, Chief Executive Officer and Director(1)
John F. Fairbanks		53	Vice President, Chief Financial Officer and Treasurer
George L. Gould, Ph.D.		51	Vice President, Research and Development
Kevin A. Schmidt		48	Vice President, Operations
Corby C. Whitaker		44	Senior Vice President, Sales and Marketing
Non-Employee Directors
P. Ramsay Battin		43	Director(1)
Robert M. Gervis		53	Director(1)
Craig A. Huff		49	Director(1)
Steven R. Mitchell		44	Director(1)
Mark L. Noetzel		56	Chairman of the Board(1)
William P. Noglows		56	Director-Elect(1)(2)
David J. Prend		56	Director(1)
Richard F. Reilly		66	Director(1)

(1) See “Certain Relationships and Related Person Transactions — Agreements with Stockholders” for a discussion of arrangements among our stockholders pursuant to which this director was selected.

(2) Mr. Noglows will become a director of the Company upon the consummation of this offering.

Donald R. Young has been our President, Chief Executive Officer and a member of our board of directors since November 2001. Prior to joining us, Mr. Young served as Chief Executive Officer of HighWired, a leading venture capital backed software and e-learning company. Prior to that, Mr. Young worked in the United States and abroad in a broad range of senior operating roles for Cabot Corporation, a leading global specialty chemical company. Prior to Cabot Corporation, Mr. Young worked in the investment business at Fidelity Management & Research. Mr. Young holds a BA from Harvard College and an MBA from Harvard Business School. We believe that Mr. Young possesses specific attributes that qualify him to serve as a member of our board of directors, including the perspective and experience he brings as our Chief Executive Officer, which brings historic knowledge, operational expertise and continuity to our board of directors.

John F. Fairbanks has been our Vice President, Chief Financial Officer and Treasurer since October 2006. Prior to joining us, Mr. Fairbanks was a Senior Vice President of New England Business Service, Inc., or NEBS, and served as treasurer, chief financial officer and in several senior operating roles for NEBS during his tenure. Immediately prior to joining NEBS, Mr. Fairbanks was vice president and treasurer of M/A-Com, Inc. Mr. Fairbanks holds a BA in Economics from Middlebury College and an MBA in Finance from the Wharton School at University of Pennsylvania.

George L. Gould, Ph.D. has been with us since our inception in 2001 and has served as our Vice President, Research and Development since April 2011. Prior to this role, Dr. Gould served in a variety of positions with us, most recently as our Director, Research and Development from February 2009 to April 2011 and Director, Research from June 2005 to February 2009. Prior to joining us, Dr. Gould was employed by Aspen Systems, the company from which our company was spun-off. Prior to joining Aspen Systems, Dr. Gould was a chemistry professor at the University of Illinois at Chicago. Dr. Gould holds a B.A. in Chemistry from the College of Wooster, a Ph.D. in Inorganic Chemistry from Yale University and carried out his post-doctoral training at Brookhaven National Laboratory.

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Kevin A. Schmidt has been with us since June 2004 and has served as our Vice President, Operations since February 2007. From June 2004 to February 2007, Mr. Schmidt served as our Vice President, Manufacturing. Prior to joining us, Mr. Schmidt worked 17 years for The Dow Chemical Company in business and operational leadership roles within Polystyrene, Engineering Thermoplastics, Styrofoam and Polyurethane System House Global Business Units. Mr. Schmidt holds a BS in Chemical Engineering from The Pennsylvania State University.

Corby C. Whitaker has been our Senior Vice President, Sales and Marketing since joining us in February 2012. Prior to that, Mr. Whitaker worked in senior sales, marketing and business development leadership roles in the energy, renewable energy, building materials and industrial equipment industries. From July 2010 to December 2011, Mr. Whitaker was Vice President, Sales at Solyndra LLC and from December 2007 to July 2010, Mr. Whitaker served as Vice President, Global Sales at United Solar Ovonic LLC, each solar technology companies. Prior to that, from March 2004 to December 2007, Mr. Whitaker served as Director of Sales at Johns Manville, a building materials company. Mr. Whitaker holds a B.S. in mechanical engineering from Texas A&M University.

P. Ramsay Battin has served on our board of directors since June 2008. Mr. Battin is a partner with Eastside Partners, a venture capital firm he joined in January 2014. Mr. Battin previously served as a director on the Arcapita Ventures investment team at Arcapita Inc. and he currently serves as a consultant to Arcapita Investment Management US Inc. Prior to joining Arcapita in November 2005, he was a partner with Southeastern Technology Fund, an early and growth stage venture capital firm. Mr. Battin has also served in the corporate finance departments at Lehman Brothers and Robinson-Humphrey in New York, London and Atlanta. Mr. Battin currently serves on the boards of directors of Fidelis SeniorCare and previously served as a member of the board of directors of Best Doctors, Prenova, RTO Software and SPI Dynamics. Mr. Battin holds an AB in History from Princeton University and an MBA from Harvard Business School. We believe that Mr. Battin possesses specific attributes that qualify him to serve as a member of our board of directors, including his experience building, investing in and growing technology companies and his experience with sophisticated transactions as an investment banker. In addition, because Mr. Battin has served on many boards of directors, we believe he has substantial experience regarding how boards can and should effectively oversee and manage companies, and a significant understanding of governance issues.

Robert M. Gervis has served on our board of directors since January 2011. Mr. Gervis is Managing Member and President of Epilogue, LLC, a private advisory firm he founded in April 2009. Prior to founding Epilogue, LLC, Mr. Gervis served in various senior executive positions at Fidelity Investments from July 1994 to March 2009. Mr. Gervis’ management experience during his tenure with Fidelity Investments included serving as (i) Chief Executive Officer of an oil and natural gas exploration and production company from December 2002 to March 2006; (ii) Chief Operating Officer of an international, full-service real estate development and investment company from May 2002 to June 2003; (iii) Managing Director of a private equity division from March 2002 to March 2006, which invested in a broad range of industries, including technology, biotechnology, real estate, oil and gas exploration and production and telecommunications; and (iv) President of Ballyrock Investment Advisors from April 2006 to March 2009, a registered investment adviser which managed Fidelity Investments’ structured credit business. Prior to joining Fidelity Investments, Mr. Gervis was a partner at the law firm of Weil, Gotshal & Manges. He currently also serves on the board of directors of Axiall Corporation (NYSE: AXLL); and is an investor in, and occasionally serves on the boards of, private companies primarily in the Boston area. Mr. Gervis previously served as a director of Tronox Incorporated (NYSE: TROX). Mr. Gervis holds a BS in Industrial Engineering from Lehigh University and a JD from The George Washington University. Mr. Gervis also is a CFA charterholder. We believe that Mr. Gervis possesses specific attributes that qualify him to serve as a member of our board of directors, including his extensive experience in finance, capital markets and investing, his management skills, as well as his experience with sophisticated transactions as a corporate attorney. In addition, because Mr. Gervis has served on many boards of directors, we believe he has substantial experience regarding how boards can and should effectively oversee and manage companies, and a significant understanding of governance issues.

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Craig A. Huff has served on our board of directors since September 2010, and prior to that served on our board of directors from February 2005 to August 2009. Mr. Huff is Co-Founder and Co-Chief Executive Officer of Reservoir Capital Group, or Reservoir, a privately-held investment firm with approximately $7.1 billion under management as of December 31, 2013. Reservoir invests opportunistically in both the public and private equity and debt markets with a focus on power and energy. Reservoir also starts and builds alternative investment firms. Since founding Reservoir in 1998, Mr. Huff has served on the boards of many of its portfolio companies in industries such as energy, power, agriculture, aircraft leasing and insurance. He has also been instrumental in the formation and development of a variety of hedge funds and private investment firms. Previously, Mr. Huff was a Partner at Ziff Brothers Investments and, prior to business school, served in the U.S. Navy as a nuclear submarine officer and nuclear engineer. Mr. Huff is the President of the Board of Trustees of St. Bernard’s School in New York City. He is a Trustee of the Princeton Theological Seminary and serves as Chairman of its Investment Committee. Mr. Huff is also a member of the Advisory Board of the Center for Regenerative Medicine (Harvard Stem Cell Institute/Massachusetts General Hospital) and several other nonprofit organizations. Mr. Huff graduated magna cum laude from Abilene Christian University with a B.S. in Engineering Physics. He also completed his MBA at Harvard Business School, where he graduated with high distinction as a Baker Scholar. We believe that Mr. Huff possesses specific attributes that qualify him to serve as a member of our board of directors, including his experience building, investing in and growing companies and his executive experience as Co-Chief Executive Officer of Reservoir, as well as his scientific background. In addition, because Mr. Huff has served on many boards of directors, we believe he has substantial experience regarding how boards can and should effectively oversee and manage companies, and a significant understanding of governance issues.

Steven R. Mitchell has served on our board of directors since August 2009. Mr. Mitchell has served as the managing director of Argonaut Private Equity, LLC, or Argonaut, since November 2004. Prior to joining Argonaut, Mr. Mitchell was a principal in both Radical Incubation and 2929 Entertainment. He currently serves on the boards of directors of Global Client Solutions, LLC; Yulex Corporation; Stepstone Group; Green Hills Software, Inc.; Newco Valves, LLC; S&R Compression, LLC; DMB Pacific, LLC; 360 Degree Solar Holdings, Inc.; Norberg-IES, LLC; Otis Eastern Services, LLC; Specific Systems, LLC; and Global Technology Partners, LLC. From 1996 to 1999, Mr. Mitchell was a corporate attorney at Gibson, Dunn & Crutcher. Mr. Mitchell holds a BBA in Marketing from Baylor University and a JD from the University of San Diego School of Law. We believe that Mr. Mitchell possesses specific attributes that qualify him to serve as a member of our board of directors, including his experience building, investing in and growing several manufacturing, technology and product companies and his experience with sophisticated transactions as a corporate attorney. In addition, because Mr. Mitchell has served on many boards of directors, we believe he has substantial experience regarding how boards can and should effectively oversee and manage companies, and a significant understanding of governance issues.

Mark L. Noetzel has served on our board of directors since December 2009. Mr. Noetzel has worked as a consultant to a number of public and private companies since May 2009. From June 2007 to May 2009, Mr. Noetzel was president and chief executive officer of Cilion, Inc., a biofuels company. Prior to joining Cilion in 2007, he had served in several senior positions at BP plc, including Group Vice President, Global Retail, from 2003 until 2007, Group Vice President, B2B Fuels and New Markets, during 2001 and 2002 and Group Vice President, Chemicals, from 1997 until 2001. Prior to those senior management roles with BP plc, Mr. Noetzel served in other management and non-management roles with Amoco from 1981 until BP plc acquired Amoco Corporation in 1998. Mr. Noetzel is also chairman of the board of directors of Axiall Corporation (NYSE: AXLL), created by the merger of Georgia Gulf Corporation and the commodity chemicals business of PPG. Mr. Noetzel currently serves on the boards of two private development stage technology companies, Siluria Technologies Inc. and Novogy Inc. Mr. Noetzel holds a BA in Political Science from Yale University and an MBA from the Wharton School at University of Pennsylvania. We believe that Mr. Noetzel possesses specific attributes that qualify him to serve as a member and chairman of our board of directors, including more than ten years’ experience in senior executive management roles with large, international businesses within the chemical and fuel industries and his experience as chairman of the board of an existing public company.

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William P. Noglows will become a director of the Company upon the consummation of this offering. Mr. Noglows previously served on our board of directors from January 2011 to April 2013. Mr. Noglows has served as Chairman, President and Chief Executive Officer of Cabot Microelectronics Corporation since November 2003. Mr. Noglows also is a director of Littelfuse, Inc. From 1984 through 2003, he served in various management positions at Cabot Corporation, culminating in serving as an executive vice president and general manager. Mr. Noglows had previously served as a director of Cabot Microelectronics from December 1999 until April 2002. Mr. Noglows received his B.S. in Chemical Engineering from the Georgia Institute of Technology. We believe that Mr. Noglows possesses specific attributes that qualify him to serve as a member of our board of directors, including his experience as chief executive officer of a leading public company and his expertise in developing technology. In addition, because Mr. Noglows has served on boards of directors of two other public companies, we believe he has significant experience regarding how boards can and should effectively oversee and manage companies, and a significant understanding of governance issues.

David J. Prend has served on our board of directors since May 2001. Mr. Prend is the cofounder of RockPort Capital Partners and has served as a managing general partner since 1998. Mr. Prend began his career in the energy industry as an engineer at Bechtel Corporation where he worked in the area of advanced energy technologies. From 1984 until 1987, he worked at Amoco Corporation in the Treasurer’s Department, and in the chemical and upstream oil and gas subsidiaries of Amoco. He later joined Shearson Lehman Hutton Inc. in their Natural Resources Investment Banking Group where he advised companies in the energy, mining and forest products industries. In 1990, he joined Salomon Brothers where he was promoted to Managing Director and headed the Global Energy Investment Banking Group. He currently serves on the boards of directors of Achates Power, Inc., Enki Technology, Inc., GlassPoint Solar, Inc., InVisage Technologies, Inc., Solar Universe, Inc. and SustainX, Inc. He is also a member of the National Advisory Council to the National Renewable Energy Laboratory, or NREL, chairman of the Solar Technology Review Panel for NREL and chairman of the E.O. Wilson Biodiversity Foundation. Mr. Prend served on the board of the National Venture Capital Association from 2007 to 2011. In addition, Mr. Prend was formerly a director of Satcon Technology Corporation. He holds a BS in Civil Engineering from University of California at Berkeley and an MBA from Harvard Business School. We believe that Mr. Prend possesses specific attributes that qualify him to serve as a member of our board of directors and as a member of our compensation committee, including his experience in the renewable energy sector and venture capital industries. In addition, because Mr. Prend has served on many boards of directors, we believe he has substantial experience regarding how boards can and should effectively oversee and manage companies, and a significant understanding of governance issues.

Richard F. Reilly has served on our board of directors since July 2010. For 31 years prior to his retirement in 2009, Mr. Reilly specialized in audits of manufacturing, technology and distribution companies with KPMG LLP, with 28 years in the role of senior audit partner. Prior to his tenure with KPMG LLP Mr. Reilly worked in private industry, serving in various accounting management roles in technology and manufacturing companies. Mr. Reilly also served for ten years in the U.S. Army reserve as a combat engineer officer. Mr. Reilly currently serves as a member of the board of trustees and as chair of the audit committee of Perkins School for the Blind, a non-profit institution headquartered in Boston, Massachusetts and as a member of the finance and audit committee for The Clergy Funds of the Archdiocese of Boston. From November 2012 to December 2013, Mr. Reilly has also served as a consultant to a Fortune 500 company related to finance, controls and governance issues at its subsidiary in India. Mr. Reilly holds a BS in Business Administration from Northeastern University and is a Certified Public Accountant. We believe that Mr. Reilly possesses specific attributes that qualify him to serve as a member of our board of directors and to serve as chair of our audit committee, including a deep understanding of accounting principles and financial reporting rules and regulations, acquired over the course of his career at KPMG LLP and in private industry. In addition, we believe Mr. Reilly has significant experience overseeing, from an independent auditor’s perspective, the financial reporting processes of large public companies in a variety of industries with a global presence.

Composition of Our Board of Directors

Our board of directors currently consists of eight members, seven of whom are non-employee directors. Our directors hold office until their successors have been elected and qualified or until the earlier of their death, resignation or removal. There are no family relationships among any of our directors or executive officers.

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In accordance with our restated certificate of incorporation and restated by-laws, our board of directors will be divided into three classes with staggered three-year terms. At each annual meeting of stockholders commencing with the meeting in 2015, the successors to the directors whose terms then expire will be elected to serve until the third annual meeting following the election. At the closing of the offering made hereby, our directors will be divided among the three classes as follows:

• the Class I directors will be Messrs.        ,         and         and their terms will expire at the annual meeting of stockholders to be held in 2015;

• the Class II directors will be Messrs.        ,         and         and their terms will expire at the annual meeting of stockholders to be held in 2016; and

• the Class III directors will be Messrs.        ,         and         and their terms will expire at the annual meeting of stockholders to be held in 2017.

Our restated certificate of incorporation provides that the authorized number of directors comprising our board of directors shall be fixed by our restated by-laws. Any additional directorships resulting from an increase in the number of directors will be distributed among the three classes so that each class will consist of approximately one-third of the directors.

Director Independence

Under applicable NYSE rules, a director will qualify as “independent” if our board of directors affirmatively determines that he or she has no material relationship with Aspen Aerogels (either directly or as a partner, stockholder or officer of an organization that has a relationship with us). Our board of directors will establish guidelines to assist it in determining whether a director has such a material relationship. Ownership of a significant amount of our stock, by itself, does not constitute a material relationship.

Pursuant to NYSE rules, a director employed by us cannot be deemed to be an “independent director,” and consequently Mr. Young does not qualify as an independent director.

The applicable rules and regulations of the NYSE require us to have a majority of independent directors within one year of the date our common stock is listed on the NYSE. Our board has determined that each of Robert M. Gervis, Mark L. Noetzel, Richard F. Reilly, William P. Noglows and             meet the categorical standards described above, that none of these directors, including Mr. Noglows upon his joining the board, has a material relationship with us and that each of these directors is “independent” as determined under Section 303A.02 of the NYSE Listed Company Manual.

Committees of the Board of Directors

Our board of directors has established an audit committee, a compensation and leadership development committee, or compensation committee, and a nominating and governance committee. Each committee operates under a charter approved by our board of directors. The composition and function of each of these committees are described below.

Audit Committee. Upon the completion of this offering, our audit committee will be comprised of Messrs.        ,          and         . Mr.         will be chairman of the committee. Our board of directors has determined that Mr.          is an audit committee financial expert, as defined by the rules of the SEC, and satisfies the financial sophistication requirements of applicable NYSE rules. Our audit committee is authorized to, among other matters:

• approve and retain the independent auditors to conduct the annual audit of our financial statements;

• review the proposed scope and results of the audit;

• review and pre-approve audit and non-audit fees and services;

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• review accounting and financial controls with the independent auditors and our financial and accounting staff;

• review and approve transactions between us and our directors, officers and affiliates;

• recognize and prevent prohibited non-audit services;

• establish procedures for complaints received by us regarding accounting matters;

• oversee internal audit functions, if any; and

• prepare the report of the audit committee that the rules of the Securities and Exchange Commission require to be included in our annual meeting proxy statement.

The applicable rules and regulations of the SEC and NYSE require us to have one independent audit committee member upon the listing of our common stock on NYSE, a majority of independent members within 90 days of the effective date of the registration statement of which this prospectus forms a part and all independent audit committee members within one year of the date of the completion of this offering.

Compensation Committee. Upon completion of this offering, our compensation committee will be comprised of Messrs.         ,         and        . Mr.         will be chairman of the committee. Our compensation committee is authorized to, among other matters:

• review and recommend the compensation arrangements for management;

• establish and review general compensation policies with the objective to attract and retain superior talent, to reward individual performance and to achieve our financial goals;

• administer our stock incentive and purchase plans;

• ensure appropriate leadership development and succession planning is in place;

• oversee the evaluation of management; and

• prepare the report of the compensation committee that the rules of the Securities and Exchange Commission require to be included in our annual meeting proxy statement.

The applicable rules and regulations of the NYSE require us to have one independent compensation committee member upon the closing of this offering, a majority of independent members within 90 days of the date our common stock is listed on the NYSE and all independent compensation committee members within one year of the NYSE listing date.

Nominating and Governance Committee. Upon completion of this offering, our nominating and governance committee will be comprised of Messrs.        ,         and        . Mr.        will be the chairman of the committee. Our nominating and governance committee is authorized to, among other matters:

• identify and nominate candidates for election to the board of directors;

• review and recommend the compensation arrangements for certain members of our board of directors;

• develop and recommend to the board of directors a set of corporate governance principles applicable to our company; and

• oversee the evaluation of our board of directors.

The applicable rules and regulations of the NYSE require us to have one independent nominating and governance committee member upon the closing of this offering, a majority of independent members within 90 days of the date our common stock is listed on the NYSE and all independent nominating and governance committee members within one year of the NYSE listing date.

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Compensation Committee Interlocks and Insider Participation

No member of our compensation committee has at any time been an employee of ours. None of our executive officers serves as a member of another entity’s board of directors or compensation committee that has one or more executive officers serving as a member of our board of directors or compensation committee.

Corporate Governance Guidelines

Our board of directors will adopt corporate governance guidelines to assist the board in the exercise of its duties and responsibilities and to serve the best interests of our company and our stockholders. These guidelines, which provide a framework for the conduct of our board’s business, will provide that:

• our board’s principal responsibility is to oversee the management of Aspen Aerogels;

• a majority of the members of our board of directors shall be independent directors;

• directors have full and free access to management and employees of our company, and the right to hire and consult with independent advisors at our expense;

• all directors are expected to participate in continuing director education on an ongoing basis; and

• at least annually, our board of directors and its committees will conduct self-evaluations to determine whether they are functioning effectively.

Code of Business Conduct and Ethics

We will adopt a code of business conduct and ethics that will apply to all of our employees, officers and directors, including those officers responsible for financial reporting. We expect that any amendments to the code, or any waivers of its requirements, will be disclosed on our website.

Limitation of Directors’ and Officers’ Liability and Indemnification

The Delaware General Corporation Law authorizes corporations to limit or eliminate, subject to specified conditions, the personal liability of directors to corporations and their stockholders for monetary damages for breach of their fiduciary duties. Our existing fourth amended and restated certificate of incorporation, as amended, and the restated certificate of incorporation to be effective upon the completion of this offering limits the liability of our directors to the fullest extent permitted by Delaware law.

We have obtained director and officer liability insurance to cover liabilities our directors and officers may incur in connection with their services to us. Our restated certificate of incorporation and restated by-laws to be effective upon the completion of this offering also provide that we will indemnify and advance expenses to any of our directors and officers who, by reason of the fact that he or she is one of our officers or directors, is involved in a legal proceeding of any nature. We will repay certain expenses incurred by a director or officer in connection with any civil, criminal, administrative or investigative action or proceeding, including actions by us or in our name. Such indemnifiable expenses include, to the maximum extent permitted by law, attorney’s fees, judgments, fines, ERISA excise taxes, penalties, settlement amounts and other expenses reasonably incurred in connection with legal proceedings. A director or officer will not receive indemnification if he or she is found not to have acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, our best interest.

We have entered into indemnification agreements with each of our non-employee directors and will enter into similar agreements with certain officers. These agreements provide that we will, among other things, indemnify and advance expenses to our directors and officers for certain expenses, including attorneys’ fees, judgments, fines and settlement amounts incurred by any such person in any investigation, action or proceeding, including any action by us arising out of such person’s services as our director or officer, or any other company or enterprise to which the person provides services at our request. We believe that these provisions and agreements are necessary to attract and retain qualified persons as directors and officers.

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Such limitation of liability and indemnification does not affect the availability of equitable remedies. In addition, we have been advised that in the opinion of the SEC, indemnification for liabilities arising under the Securities Act is against public policy as expressed in the Securities Act and is therefore unenforceable.

There is no pending litigation or proceeding involving any of our directors, officers, employees or agents in which indemnification will be required or permitted. We are not aware of any threatened litigation or proceeding that may result in a claim for such indemnification.

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EXECUTIVE AND DIRECTOR COMPENSATION

The following discussion relates to the compensation of our “named executive officers,” including our President and Chief Executive Officer, Donald R. Young, and our two most highly compensated executive officers (other than our President and Chief Executive Officer), John F. Fairbanks, our Vice President, Chief Financial Officer and Treasurer, and Corby C. Whitaker, our Senior Vice President, Sales and Marketing.

Summary Compensation Table

The following table sets forth information regarding compensation earned by our named executive officers during our fiscal years ended December 31, 2013 and 2012.

Name and Principal Position	Year		Salary ($)(1)		Bonus ($)(2)		Option Awards ($)(3)		Non-Equity Incentive Plan Compensation ($)(4)		All Other Compensation ($)(5)		Total ($)
Donald R. Young		2013	$	450,000	$	0	$	3,159,849	$	526,441	$	0	$	4,136,290
President and Chief Executive Officer		2012		362,731		0		3,034,711		0		12,669		3,410,111
John F. Fairbanks		2013		265,009		0		758,363		145,822		10,124		1,179,318
Vice President, Chief Financial Officer and Treasurer		2012		255,280		0		77,962		0		9,396		342,638
Corby C. Whitaker		2013		281,029		0		505,576		154,637		23,706		964,948
Senior Vice President, Sales and Marketing		2012		248,557		35,000		886,630		0		98,238		1,268,425

(1) Mr. Whitaker was hired January 30, 2012 with an annual base salary of $275,000.

(2) Represents a hiring bonus paid to Mr. Whitaker during 2012 pursuant to the terms of his employment.

(3) These amounts represent the aggregate grant date fair value for option awards granted to our named executive officers, computed in accordance with ASC Topic 718. Valuation assumptions are described in the notes to our financial statements included elsewhere in this prospectus. See our discussion of stock-based compensation under “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Critical Accounting Policies and Estimates — Stock-based Compensation.”

A portion of the 2013 option awards for each named executive officer includes options that were issued in exchange for the forfeiture of options, including the option awards made in 2012 disclosed in the table, then held by the named executive officer. Specifically, in 2013, Mr. Young was granted an option to purchase 6,191,844 shares of our common stock at an exercise price of $0.09 per share in exchange for the forfeiture of options to purchase 1,048,386 shares of our common stock at a weighted average exercise price of $7.05 per share; Mr. Fairbanks was granted an option to purchase 1,486,042 shares of our common stock at an exercise price of $0.09 per share in exchange for the forfeiture of options to purchase 122,980 shares of our common stock at a weighted average exercise price of $6.34 per share; and Mr. Whitaker was granted an option to purchase 990,695 shares of our common stock at an exercise price of $0.09 per share in exchange for the forfeiture of options to purchase 89,999 shares of our common stock at a weighted average exercise price of $17.80 per share. Due to the de minimis value of the forfeited options, which had exercise prices that exceeded the exercise price of these 2013 option awards, the incremental grant date fair value is equal to the grant date fair value of the 2013 option awards issued in the exchange.

In addition, a portion of the 2013 option awards for each named executive officer includes options subject to performance-based vesting provisions. The maximum grant date fair value of these performance-based options which is included in the amount set forth in the table for each of Messrs. Young, Fairbanks and Whitaker is $2,439,738, $585,537, and $390,358, respectively.

(4) Represents the amount awarded to the named executive officer under the Aspen Aerogels, Inc. Bonus Plan for 2013 and 2012, respectively.

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(5) Consists of cash payments in lieu of vacation pursuant to company policy except with respect to Mr. Whitaker for 2012. For 2012, the amount paid to Mr. Whitaker consists of reimbursement for certain relocation expenses, including moving expenses, expenses relating to the sale of his former residence and the search for and purchase of a new residence in the Northborough, Massachusetts area, and tax gross-up payments for such expenses.

Narrative Disclosure to Summary Compensation Table

Employment Arrangements with Our Named Executive Officers

Donald R. Young

We entered into an amended and restated executive agreement with Mr. Young on August 5, 2011, which was subsequently amended on October 23, 2012. Pursuant to this agreement, Mr. Young continues to serve as our Chief Executive Officer on an at-will basis, Mr. Young’s annual base salary was set at $450,000 per year, and Mr. Young is eligible to receive an annual performance-based bonus as determined by our board of directors with a target of 75% of his base salary. Mr. Young’s base salary may be increased, but not decreased, at the discretion of our board of directors or a committee thereof.

Mr. Young is entitled to certain benefits in connection with a termination of his employment or a change of control as discussed below under “— Potential Payments Upon Termination or Change of Control.”

Other Named Executive Officers

We entered into an amended and restated executive agreement with Mr. Fairbanks on August 5, 2011, which was subsequently amended on November 6, 2012. We also entered into an executive agreement with Mr. Whitaker upon his employment with us on January 30, 2012. Pursuant to these agreements, Mr. Fairbanks and Mr. Whitaker serve as executive officers on an at-will basis. We refer to the agreements with Messrs. Fairbanks and Whitaker, as well as our executive agreement with Mr. Young described above, as the executive agreements. Pursuant to these agreements, the annual base salaries for Messrs. Fairbanks and Whitaker were set at $244,300 and $275,000 per year, respectively, and they are eligible to receive an annual performance-based bonus in an amount, if any, to be determined by our board of directors or a committee thereof. The annual base salaries set forth in these agreements may be increased, but not decreased, at the discretion of our board of directors or a committee thereof. In March 2013, Messrs. Fairbanks and Whitaker’s annual base salaries were increased to $267,104 and $283,250 per year, respectively.

In addition, in connection with the negotiation of Mr. Whitaker’s employment in 2012, we agreed pay Mr. Whitaker a signing bonus of $35,000 and we also agreed to reimburse him for certain relocation expenses, including moving expenses, expenses relating to the sale of his former residence and the search for and purchase of a new residence in the Northborough, Massachusetts area, and tax gross-up payments for such expenses.

Messrs. Fairbanks and Whitaker are entitled to certain benefits in connection with a termination of their employment or a change of control as discussed below under “— Potential Payments Upon Termination or Change of Control.”

Employment, Confidentiality and Non-Competition Agreements

Each of our named executive officers has also entered into an employment, confidentiality and non-competition agreement. Among other things, this agreement obligates each named executive officer to refrain from disclosing any of our proprietary information received during the course of employment and to assign to us any inventions conceived or developed during the course of employment. Additionally, each of our named executive officers is prohibited from (i) competing with us for a period of one year following termination of employment and (ii) soliciting or interfering with our business relationship with any of our existing clients, customers, business partners or employees for a period of two years.

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2013 Stock Option Awards

On August 7, 2013, each named executive officer was granted an option in exchange for the forfeiture of options then held by the named executive officer. Specifically, Mr. Young was granted an option to purchase 6,191,844 shares of our common stock at an exercise price of $0.09 per share in exchange for the forfeiture of options to purchase 1,048,386 shares of our common stock at a weighted average exercise price of $7.05 per share; Mr. Fairbanks was granted an option to purchase 1,486,042 shares of our common stock at an exercise price of $0.09 per share in exchange for the forfeiture of options to purchase 122,980 shares of our common stock at a weighted average exercise price of $6.34 per share; and Mr. Whitaker was granted an option to purchase 990,695 shares of our common stock at an exercise price of $0.09 per share in exchange for the forfeiture of options to purchase 89,999 shares of our common stock at a weighted average exercise price of $17.80 per share. Each of these new options vested with respect to 40% of the shares on August 7, 2013 and the remaining 60% of the shares vest in equal monthly installments over the 36 months following August 7, 2013. These options will expire 10 years from the date of grant.

In addition, on August 7, 2013, each named executive officer was granted an option that is subject to performance-based vesting provisions. Specifically, Mr. Young was granted an option to purchase 21,671,454 shares of our common stock, Mr. Fairbanks was granted an option to purchase 5,201,147 shares of our common stock and Mr. Whitaker was granted an option to purchase 3,467,432 shares of our common stock. Each of these options has an exercise price of $0.09 per share. In connection with this offering, the number of shares subject to these options shall be reduced to a number of shares that, when combined with the number of shares subject to the holder’s total option holdings, shall equal a target percentage of our common stock deemed outstanding immediately prior to the offering. The target percentage for each of Messrs. Young, Fairbanks and Whitaker are 5.625%, 1.250% and 0.833%, respectively. The vesting of these options is contingent upon the consummation of this offering. Subject to and in the event of the consummation of this offering, 40% of the shares subject to these options, as adjusted, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. These options will expire 10 years from the date of grant.

Under the terms of the options granted to our named executive officers on August 7, 2013, in the event of a change of control of the Company, 12 months of the above described vesting schedules will be accelerated, provided that the vesting of the performance-based options is contingent upon the consummation of this offering. Under our executive agreements with Messrs. Young and Fairbanks, in the event that we terminate their options in connection with a change of control or in the event of a change of control termination (defined below), their options will vest immediately prior to such transaction. Under the terms of our agreement with Mr. Whitaker, in the event we terminate his options in connection with a change of control or in the event of a change of control termination, his then unvested options with respect to any stock options that otherwise would have vested over the next two anniversaries of the vesting start date following the change of control or termination, will vest on the date of the change of control or termination, as applicable.

Cash Bonus Plan

Upon the recommendation of our compensation committee, our board of directors approved our employee cash bonus plan in April 2012. The plan is administered by the compensation committee; however, the compensation committee may delegate some of its duties to the officers of the Company. The plan provides that participants shall be eligible to receive a cash bonus over a performance period based on goals established by the administrator which may include attaining revenue goals, an adjusted EBITDA goal, an individual goal or such other performance goals as shall be established by the administrator from time to time. Each participant shall receive a participant letter setting forth a percentage allocation of a target award which shall be based upon a percentage of base salary or set forth as a dollar amount. The participation letters shall also set forth minimum threshold achievement levels applicable to each goal and may set forth additional payments above the target award amount in the event that one or more goals are exceeded. Following completion of the performance period, the administrator shall determine the level of performance achieved for each goal and shall approve and certify the amount of the cash payments to be made.

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If a participant voluntarily terminates employment during a performance period, the participant will not be eligible for a payment. If a participant is terminated by us other than for cause or retires, as set forth in any retirement policy then in effect, the participant will receive a prorated payout based on the date of termination of employment and achievement of the goals at such time as payment is otherwise made to the other participants under the plan. All participants shall receive a payment no later than March 15 of the calendar year immediately following the performance period. The administrator may revise or terminate the plan at any time; but no amendment or termination shall be effective without the consent of a participant if it would adversely impact the economic benefit of an outstanding award thereunder.

2014 Bonus Awards

Upon the recommendation of our compensation committee, our board of directors approved the target bonus amounts and goals for fiscal 2014 on December 18, 2013. Each named executive officer’s 2014 bonus award amount will be determined based on the following performance goals for fiscal 2014: 33% based upon the achievement of total revenue and 67% based on adjusted EBITDA goals for fiscal 2014. Achievement of a predetermined adjusted EBITDA threshold is required before any bonus may be earned under the plan. As set forth in the amendment to Mr. Young’s executive agreement dated October 23, 2012, Mr. Young’s target bonus amount has been set at 75% of his annual base salary plus an additional 2.475% of annual base salary for every 1% by which actual revenue exceeds the target amount and an additional 0.5025% of annual base salary for every 1% by which actual adjusted EBITDA exceeds the target amount.

Messrs. Fairbanks and Whitaker’s target bonus amounts have been set at 35% of their respective base salaries plus an additional 1.155% of annual base salary for every 1% by which actual revenue exceeds the target amount and an additional 0.2345% of annual base salary for every 1% by which actual adjusted EBITDA exceeds the target amount.

2013 Bonus Awards and Payments

Upon the recommendation of our compensation committee, our board of directors approved the performance goals and target award amounts for fiscal 2013 on December 17, 2012. Each named executive officer’s 2013 bonus award amount was determined based on the following performance goals: 50% based upon the achievement of total revenue and 50% based on adjusted EBITDA goals for fiscal 2013. Achievement of a predetermined adjusted EBITDA threshold was also required before any bonus could be earned under the plan. As set forth in the amendment to Mr. Young’s executive agreement dated October 23, 2012, Mr. Young’s target bonus amount was 75% of his annual base salary plus an additional 3.75% of annual base salary for every 1% by which actual revenue exceeded the target amount and an additional 0.37% of annual base salary for every 1% by which actual adjusted EBITDA exceeded the target amount.

Messrs. Fairbanks and Whitakers’ target bonus amounts were set at 35% of their respective base salaries plus an additional 1.75% of annual base salary for every 1% by which actual revenue exceeded the target amount and an additional 0.17% of annual base salary for every 1% by which actual adjusted EBITDA exceeded the target amount.

As a result of meeting and exceeding the 2013 performance goals, our compensation committee recommended and our board of directors approved 2013 bonus payments under our bonus plan to Messrs. Young, Fairbanks and Whitaker of $526,441, $145,822 and $154,637, respectively.

2012 Bonus Awards and Payments

Upon the recommendation of our compensation committee, our board of directors approved the performance goals and target award amounts for fiscal 2012 on April 2, 2012 at the time the cash bonus plan was finalized. The board of directors approved a target bonus award for Mr. Young of 50% of his annual base salary

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and for Messrs. Fairbanks and Whitaker of 35% of their respective annual base salaries. Each named executive officer’s 2012 bonus award amount was determined based on the following performance goals: 50% based upon the achievement of total revenue and 50% based on adjusted EBITDA goals for fiscal 2012. The amount earned was to be increased or decreased based on our performance against such goals. In addition, achievement of a predetermined adjusted EBITDA threshold was required before any bonus could be earned under the plan. As a result of the failure of actual adjusted EBITDA to exceed the predetermined adjusted EBITDA threshold for fiscal year 2012, no bonus was earned by any of the named executive officers pursuant to the plan.

Outstanding Equity Awards at Fiscal Year-End

The following table sets forth information regarding stock options held by our named executive officers as of December 31, 2013.

	Option Awards
Name	Number of Securities Underlying Unexercised Options (#) Exercisable			Number of Securities Underlying Unexercised Options (#) Unexercisable		Equity Incentive Plan Awards: Number of Securities Underlying Unexercised Unearned Options (#)			Option Exercise Price ($)(5)		Option Expiration Date
Donald R. Young		2,889,527	(1)		3,302,317		0		$	0.09		8/7/2023	(3)
		0			0		21,671,454	(4)	$	0.09		8/7/2023
		56,485	(2)		0		0		$	2.20		11/11/2019
John F. Fairbanks		693,486			792,556		0		$	0.09		8/7/2023	(3)
		0			0		5,201,147	(4)	$	0.09		8/7/2023
Corby C. Whitaker		462,324			528,371		0		$	0.09		8/7/2023	(3)
		0			0		3,467,432	(4)	$	0.09		8/7/2023

(1) Includes options to purchase 600,000 shares of our common stock transferred to Mr. Young’s children in December 2013.

(2) Includes options to purchase 16,485 shares of our common stock transferred to Mr. Young’s children in 2010, 2011 and 2012, and options to purchase 40,000 shares of our common stock transferred to the Young Family Trust in 2012.

(3) These options to purchase shares of our common stock vested as to 40% of the shares on August 7, 2013 and thereafter 1.667% of the shares vest in equal monthly installments over 36 months. In the event of a change of control of the Company, this vesting schedule will be accelerated by 12 months and will be subject to the change of control termination provisions of the employment agreements for such executive officers or described under “—Retirement Payments—Potential Payments Upon Termination or Change of Control”.

(4) In connection with this offering, the number of shares subject to these options shall be reduced to a number of shares that, when combined with the number of shares subject to the holder’s total option holdings, shall equal a target percentage of our common stock deemed outstanding immediately prior to the offering. The target percentage for each of Messrs. Young, Fairbanks and Whitaker are 5.625%, 1.250% and 0.833%, respectively. The vesting of these options is contingent upon the consummation of this offering. Subject to and in the event of the consummation of this offering, 40% of the shares subject to these options, as adjusted, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. Under the terms of these options, in the event of a change of control of the Company, 12 months of this vesting schedule will be accelerated. Under our executive agreements with Messrs. Young and Fairbanks, in the event that we terminate their options in connection with a change of

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control or in the event of a change of control termination (defined below), their options will vest immediately prior to such transaction. Under the terms of our agreement with Mr. Whitaker, in the event we terminate his options in connection with a change of control or in the event of a change of control termination, his then unvested options with respect to any stock options that otherwise would have vested over the next two anniversaries of the vesting start date following the change of control or termination, will vest on the date of the change of control or termination, as applicable.

(5) The per share exercise price on the date of grant was determined by our board of directors at the time of grant. See the “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Critical Accounting Policies and Estimates — Stock-based Compensation.”

Severance and Retirement Benefits

Potential Payments Upon Termination or Change of Control

We have agreed to provide severance and change of control payments and benefits to our named executive officers under specified circumstances, as described below.

Donald R. Young

Pursuant to the terms of our amended and restated executive agreement with Mr. Young, dated August 5, 2011, as further amended October 23, 2012, (i) if we terminate Mr. Young’s employment without cause, or (ii) if he resigns within 30 days after the occurrence of an event constituting good reason (including the expiration of any applicable cure periods) or (iii) upon a change of control, if he does not receive an offer to remain employed by us in the same position that is set forth in his executive agreement at a comparable rate of compensation, bonus, benefits and other material terms for a period of at least two years following the change of control and he is terminated without cause or resigns for any reason during such two year period, which we refer to as a change of control termination, Mr. Young will receive severance payments in an amount equal to 12 months of his base salary then in effect, such amount to be paid in regular installments in accordance with our regular payroll practices. Upon such an occurrence, Mr. Young will also have the right to continue participation in all employee benefit plans and programs to which he was entitled to participate as of the date of termination for a period of 12 months following the date of such termination and to receive any accrued but unpaid bonus or commissions then owed or fully accrued.

In addition, in the event of a change of control termination, any and all then unvested options to purchase shares of our common stock will immediately vest and become exercisable. In addition, in the event that we terminate the options in connection with a merger, consolidation or sale of all or substantially all of our assets, all unvested options will vest immediately prior to such transaction.

If we terminate Mr. Young’s employment without cause or if he resigns for good reason not in connection with a change of control termination, the vesting schedule for Mr. Young’s unvested options to purchase shares of our common stock will accelerate by three months. Upon such an occurrence, Mr. Young’s vested options to purchase shares of our common stock will remain exercisable for the entire ten year term of the option and will not be subject to the general provision in our 2001 equity incentive plan that provides that an employee is required to exercise options within 90 days of termination of employment.

Mr. Young’s right to receive the severance amounts set forth above are conditioned upon Mr. Young’s execution and non-revocation within 45 days of the date of termination of a general release reasonably satisfactory to us releasing us, our officers, agents, stockholder and affiliates from any liability for any matter other than for payments under the executive agreement and contractual obligations under other written agreements.

Section 280G of the Internal Revenue Code, or the Code, denies a company a tax deduction for certain payments made to an executive in connection with a change of control if the payments exceed a certain amount.

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Section 4999 of the Code imposes on the executive an additional 20% excise tax on those payments. As a result, if the aggregate of the payments and benefits that Mr. Young receives pursuant to his executive agreement or pursuant to any other plan or agreement with us are subject to the excise tax imposed by Section 4999 of the Code, under Mr. Young’s executive agreement, we are required to reduce the amount of the aggregate payments so that they are not subject to Section 4999 of the Code unless the aggregate value of the payments and benefits on an after tax basis would be greater than if they are not reduced.

The terms “cause,” “good reason” and “change of control” in our executive agreement with Mr. Young are described below under “—Other Named Executive Officers.”

Other Named Executive Officers

Pursuant to the terms of our amended and restated executive agreement with Mr. Fairbanks dated August 5, 2011 which was subsequently amended November 6, 2012, and with Mr. Whitaker’s executive agreement dated January 30, 2012 (i) if we terminate the executive’s employment without cause, (ii) if the executive resigns within 30 days after the occurrence of an event constituting good reason (including the expiration of any applicable cure periods) or (iii) upon a change of control termination, the executive will receive severance payments in an amount equal to a fixed number of months of the executive’s base salary then in effect, such amount to be paid in regular installments in accordance with our regular payroll practices. Pursuant to these agreements, severance periods for Messrs. Fairbanks and Whitaker were set at six months and three months, respectively. Upon such an occurrence, the executive will also have the right to continue participation in all employee benefit plans and programs to which the executive was entitled to participate as of the date of termination for a fixed number of months following the date of such termination and will receive any accrued but unpaid bonuses or commissions then owed or fully earned. Pursuant to these agreements, benefits periods for Messrs. Fairbanks and Whitaker were set at six months and three months, respectively.

In addition, in the event of a change of control termination, a defined amount of then unvested options to purchase shares of our common stock will immediately vest and become immediately exercisable. In addition, in the event that we terminate the options in connection with a merger, consolidation or sale of all of substantially all of our assets, then a defined amount of then unvested options will vest immediately prior to such transaction. Under the terms of our agreement with Mr. Fairbanks, in both cases, all of the then unvested options will immediately vest. Under the terms of our agreement with Mr. Whitaker, in both cases, his then unvested options with respect to any stock options that otherwise would have vested over the next two anniversaries of the vesting start date following the termination or change of control, will vest on the date of termination or change of control, as applicable.

In addition, under the terms of our agreement with Mr. Fairbanks, if we terminate his employment without cause or if he resigns for good reason, the vesting schedule for Mr. Fairbanks’ unvested options to purchase shares of our common stock will accelerate by three months. Upon such an occurrence, his vested options to purchase shares of our common stock will remain exercisable for the entire ten year term of the option and will not be subject to the general provision in our 2001 equity incentive plan that provides that an employee is required to exercise options within 90 days of termination of employment.

Under the terms of our executive agreements with Messrs. Fairbanks and Whitaker, the executive’s right to receive the severance amounts set forth above are conditioned upon the executive’s execution and non-revocation within 45 days of the date of termination of a general release reasonably satisfactory to us releasing us, our officers, agents, stockholder and affiliates from any liability for any matter other than for payments under the executive agreement and contractual obligations under other written agreements.

Section 280G of the Code denies a company a tax deduction for certain payments made to an executive in connection with a change of control if the payments exceed a certain amount. Section 4999 of the Code imposes on the executive an additional 20% excise tax on those payments. As a result, if the aggregate of the payments

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and benefits that Mr. Fairbanks or Mr. Whitaker receives pursuant to his executive agreement or pursuant to any other plan or agreement with us are subject to the excise tax imposed by Section 4999 of the Code, under the executive’s executive agreement, we are required to reduce the amount of the aggregate payments so that they are not subject to Section 4999 of Code unless the aggregate value of the payments and benefits on an after tax basis would be greater than if they are not reduced.

“Cause” is defined under all of the executive agreements as (i) willful misconduct, dishonesty, fraud or breach of fiduciary duty to us; (ii) deliberate disregard of our lawful rules or policies, or breach of an employment or other agreement with us, which results in direct or indirect loss, damage or injury to us; (iii) the unauthorized disclosure of any of our trade secrets or confidential information; or (iv) the commission of an act which constitutes unfair competition with us or which induces any customer or supplier to breach a contract with us. Whether or not an executive has committed an act or omission of the type referred to in subparagraphs (i) through (iv) above will be determined by us with reasonable, good faith discretion, based on the facts known to us at the relevant time.

“Good Reason” is defined under all of the executive agreements as (i) any material breach by us of the executive agreement that we do not cure within thirty (30) days of receiving written notice specifying in reasonable detail the nature of such material breach provided by the executive; (ii) the demotion of the executive such that the executive no longer serves in the position set forth in the executive agreement or a material reduction in the executive’s current duties and authority in the position set forth in the executive agreement, in each case, without his consent; (iii) the written demand by us for the executive to relocate or commute more than 40 miles from Brookline, Massachusetts, in the case of Mr. Young, or Northborough, Massachusetts, in the case of all other named executive officers, without his consent; or (iv) any reduction by us in the executive’s base salary without his consent. In the case of Mr. Whitaker’s executive agreement, the 30-day cure period also applies with respect to parts (ii), (iii) and (iv) above.

“Change of Control” is defined under all of the executive agreements as the occurrence of any of the following: (i) any “person” or “group” (as such terms are used in Section 13(d)(3) of the Exchange Act (other than a person or group which is one of our shareholders as of March 17, 2010)) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of our capital stock entitling such person or group to control 50% or more of the total voting power of our capital stock entitled to vote generally in the election of directors, where any voting capital stock of which such person or group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; except in connection with our issuance of capital stock in a bona-fide financing transaction the proceeds of which are to be utilized by us for general corporate purposes or (ii) any sale or transfer of all or substantially all of our assets to another person. In addition, the executive agreements of Messrs. Young and Fairbanks specifically include the retirement or repayment of outstanding debt obligations as a general corporate purpose for purposes of this definition.

401(k) Retirement Plan

We maintain a 401(k) retirement plan that is intended to be a tax-qualified defined contribution plan under Section 401(k) of the Code. In general, all of our employees who have attained 21 years of age are eligible to participate upon commencement of their employment, if they are permanent employees, and upon completion of a service requirement not exceeding one year for part-time and temporary employees. The 401(k) plan includes a salary deferral arrangement pursuant to which participants may elect to reduce their current compensation by up to the statutorily prescribed limit, equal to $17,500 in 2013, plus $5,500 for individuals aged 50 and over, and have the amount of the reduction contributed to the 401(k) plan. We do not currently match any 401(k) contributions.

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Director Compensation

The following table shows the total compensation paid or accrued during the fiscal year ended December 31, 2013 to each of our non-employee directors who served during the year.

Name	Fees Earned or Paid in Cash		Option Awards(1)		Total
P. Ramsay Battin	$	0	$	0	$	0
Robert M. Gervis(2)		39,750		313,827		353,577
Craig A. Huff		0		0		0
Steven R. Mitchell		0		0		0
Mark L. Noetzel(3)		65,500		372,555		438,055
William P. Noglows(4)		10,000		0		10,000
David J. Prend		0		0		0
Richard F. Reilly(5)		45,000		323,003		368,003

(1) These amounts represent the aggregate grant date fair value for option awards granted to our directors, computed in accordance with ASC Topic 718. Valuation assumptions are described in the notes to our financial statements included elsewhere in this prospectus. See our discussion of stock-based compensation under “Management’s Discussion and Analysis of Financial Condition and Results of Operations — Critical Accounting Policies and Estimates — Stock-based Compensation.”

(2) On December 20, 2013, Mr. Gervis was granted an option to purchase 427,500 shares of our common stock at an exercise price of $0.18 per share in exchange for the forfeiture of options held by Mr. Gervis to purchase 29,300 shares of our common stock at a weighted average exercise price of $14.91 per share. This option to purchase shares of our common stock vested as to 40% of the shares as of August 7, 2013 and thereafter 1.667% of the shares vest in equal monthly installments over 36 months. In the event that there is a change of control of the Company, that Mr. Gervis is not reelected as a director at any time prior to this offering or that Mr. Gervis is removed by us other than for cause, all shares subject to this option will be fully vested. As of December 31, 2013, 202,506 shares of common stock were vested under this option.

Mr. Gervis was granted an additional option on December 20, 2013 to purchase 1,496,250 shares of our common stock at an exercise price of $0.18 per share. Upon the consummation of this offering, the number of shares subject to this option will be reduced such that the Mr. Gervis’ total option holdings will equal 0.36% of our common stock deemed outstanding immediately prior to the offering. Subject to and in the event of the consummation of this offering, 40% of the shares subject to these options, as adjusted, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. In the event that there is a change of control of the Company, that Mr. Gervis is not reelected as a director at any time prior to this offering or that Mr. Gervis is removed by us other than for cause, all shares subject to this option will be fully vested. As of December 31, 2013, no shares of common stock were vested under this option. The maximum grant date fair value of these performance-based options included in the table above is $242,648.

(3) On December 20, 2013, Mr. Noetzel was granted an option to purchase 507,500 shares of our common stock at an exercise price of $0.18 per share in exchange for the forfeiture of options held by Mr. Noetzel to purchase 35,300 shares of our common stock at a weighted average exercise price of $6.50 per share. This option to purchase shares of our common stock vested as to 40% of the shares as of August 7, 2013 and thereafter 1.667% of the shares vest in equal monthly installments over 36 months. In the event that there is a change of control of the Company, that Mr. Noetzel is not reelected as a director at any time prior to this offering or that Mr. Noetzel is removed by us other than for cause, all shares subject to this option will be fully vested. As of December 31, 2013, 240,402 shares of common stock were vested under this option.

Mr. Noetzel was granted an additional option on December 20, 2013 to purchase 1,776,250 shares of our common stock at an exercise price of $0.18 per share. Upon the consummation of this offering, the number

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of shares subject to this option will be reduced such that the Mr. Noetzel’s total option holdings will equal 0.427% of our common stock deemed outstanding immediately prior to the offering. Subject to and in the event of the consummation of this offering, 40% of the shares subject to these options, as adjusted, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. In the event that there is a change of control of the Company, that Mr. Noetzel is not reelected as a director at any time prior to this offering or that Mr. Noetzel is removed by us other than for cause, all shares subject to this option will be fully vested. As of December 31, 2013, no shares of common stock were vested under this option. The maximum grant date fair value of these performance-based options included in the table above is $288,056.

(4) William P. Noglows resigned as a director effective April 29, 2013. Amount noted is for service through the date of resignation. Mr. Noglows will become a director again upon the consummation of this offering.

(5) On December 20, 2013, Mr. Reilly was granted an option to purchase 440,000 shares of our common stock at an exercise price of $0.18 per share in exchange for the forfeiture of options held by Mr. Reilly to purchase 30,300 shares of our common stock at a weighted average exercise price of $13.44 per share. This option to purchase shares of our common stock vested as to 40% of the shares as of August 7, 2013 and thereafter 1.667% of the shares vest in equal monthly installments over 36 months. In the event that there is a change of control of the Company, that Mr. Reilly is not reelected as a director at any time prior to this offering or that Mr. Reilly is removed by us other than for cause, all shares subject to this option will be fully vested. As of December 31, 2013, 208,428 shares of common stock were vested under this option.

Mr. Reilly was granted an additional option on December 20, 2013 to purchase 1,540,000 shares of our common stock at an exercise price of $0.18 per share.Upon the consummation of this offering, the number of shares subject to this option will be reduced such that the Mr. Reilly’s total option holdings will equal 0.37% of our common stock deemed outstanding immediately prior to the offering. Subject to and in the event of the consummation of this offering, 40% of the shares subject to these options, as adjusted, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. In the event that there is a change of control of the Company, that Mr. Reilly is not reelected as a director at any time prior to this offering or that Mr. Reilly is removed by us other than for cause, all shares subject to this option will be fully vested. As of December 31, 2013, no shares of common stock were vested under this option. The maximum grant date fair value of these performance-based options included in the table above is $249,743.

Our practice in recent years has been to pay each non-employee director who is not affiliated with our major shareholders an annual retainer of $30,000, or $60,000 in the case of the chairperson, for their services. If we hold more than 12 board meetings in a calendar year, each non-employee director will receive a fee of $1,500 for each additional board meeting attended in person and a fee of $1,000 for each additional board meeting attended by telephone or by other means of communication. Committee members will receive additional annual retainers as follows:

Committee	Chairman		Member
Audit Committee	$	14,000	$	5,500
Compensation Committee		10,000		5,000
Nominating and Governance Committee		8,000		4,000

With respect to the audit committee, if we hold more than 12 meetings of the committee in a calendar year, each committee member will receive a fee of $1,500 for each additional committee meeting attended in person and a fee of $1,000 for each additional committee meeting attended by telephone or by other means of communication.

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With respect to the compensation committee and the nominating and governance committee, if we hold more than eight meetings of a committee in a calendar year, each committee member will receive a fee of $1,500 for each additional committee meeting attended in person and a fee of $1,000 for each additional committee meeting attended by telephone or by other means of communication.

Our practice in recent years has been to not provide any compensation to employee directors or to directors who are affiliated with our major shareholders. We have reimbursed and will continue to reimburse our non-employee directors for their reasonable expenses incurred in attending meetings of our board of directors and committees of the board of directors.

On December 20, 2013, each director other than our employee directors or directors who are affiliated with our major shareholders was granted an option in exchange for the forfeiture of options then held by such director. Specifically, Mr. Gervis was granted an option to purchase 427,500 shares of our common stock at an exercise price of $0.18 per share in exchange for the forfeiture of options to purchase 29,300 shares of our common stock at a weighted average exercise price of $14.91 per share; Mr. Noetzel was granted an option to purchase 507,500 shares of our common stock at an exercise price of $0.18 per share in exchange for the forfeiture of options to purchase 35,300 shares of our common stock at a weighted average exercise price of $6.50 per share; and Mr. Reilly was granted an option to purchase 440,000 shares of our common stock at an exercise price of $0.18 per share in exchange for the forfeiture of options to purchase 30,300 shares of our common stock at a weighted average exercise price of $13.44 per share. Each of these new options vested with respect to 40% of the shares on August 7, 2013 and the remaining 60% of the shares vest in equal monthly installments over the 36 months following August 7, 2013. In the event that there is a change of control of the Company, that such director is not reelected as a director at any time prior to this offering or that such director is removed by us other than for cause, all shares subject to such director’s option will be fully vested. These options will expire 10 years from the date of grant.

In addition, on December 20, 2013, each director other than our employee directors or directors who are affiliated with our major shareholders was granted an option that is subject to performance-based vesting provisions. Specifically, Mr. Gervis was granted an option to purchase 1,496,250 shares of our common stock, Mr. Noetzel was granted an option to purchase 1,776,250 shares of our common stock and Mr. Reilly was granted an option to purchase 1,540,000 shares of our common stock. Each of these options has an exercise price of $0.18 per share. In connection with this offering, the number of shares subject to these options shall be reduced to a number of shares that, when combined with the number of shares subject to the holder’s total option holdings, shall equal a target percentage of our common stock deemed outstanding immediately prior to the offering. The target percentage for each of Messrs. Gervis, Noetzel and Reilly are 0.36%, 0.427% and 0.37%, respectively. The vesting of these options is contingent upon the consummation of this offering. Subject to and in the event of the consummation of this offering, 40% of the shares subject to these options, as adjusted, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. In the event that there is a change of control of the Company, that such director is not reelected as a director at any time prior to this offering or that such director is removed by us other than for cause, all shares subject to such director’s option will be fully vested. These options will expire 10 years from the date of grant.

In                      2014, our board of directors adopted the non-employee director compensation policy, or our director compensation policy, that will become effective following the completion of this offering and replaces our current practice described above. The policy is designed to seek to ensure that the compensation aligns our non-employee directors’ interests with the long-term interests of our stockholders, that the structure of the compensation is simple, transparent and easy for stockholders to understand and that our non-employee directors are fairly compensated. Directors who are also our employees, such as Mr. Young, will not receive additional compensation for their services as directors.

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Pursuant to our director compensation policy, upon initial election or appointment to the board of directors, new non-employee directors receive an equity grant comprised of                 . Each year of a non-employee director’s tenure, the director will receive an equity grant comprised of                 .

In addition, pursuant to our director compensation policy, each non-employee director will be paid an annual retainer of $        , or $         in the case of the chairperson, for their services. If we hold more than      board meetings in a calendar year, each non-employee director will receive a fee of $         for each additional board meeting attended in person and a fee of $         for each additional board meeting attended by telephone or by other means of communication. Committee members will receive additional annual retainers as follows:

Committee	Chairman	Member
Audit Committee	$	$
Compensation Committee
Nominating and Governance Committee

With respect to the audit committee, if we hold more than          meetings of the committee in a calendar year, each committee member will receive a fee of $         for each additional committee meeting attended in person and a fee of $         for each additional committee meeting attended by telephone or by other means of communication.

With respect to the compensation committee and the nominating and governance committee, if we hold more than                  meetings of a committee in a calendar year, each committee member will receive a fee of $         for each additional committee meeting attended in person and a fee of $         for each additional committee meeting attended by telephone or by other means of communication.

We have reimbursed and will continue to reimburse our non-employee directors for their reasonable expenses incurred in attending meetings of our board of directors and committees of the board of directors.

Equity Incentive Plans

2014 Employee, Director and Consultant Equity Incentive Plan

Our 2014 employee, director and consultant equity incentive plan, or the 2014 equity incentive plan, which will become effective upon the closing of the offering made hereby, was adopted by our board of directors in                     2014 and approved by our stockholders in                     2014. The 2014 equity incentive plan will expire in 2024. Under our 2014 equity incentive plan, we may grant incentive stock options, non-qualified stock options, restricted and unrestricted stock awards and other stock-based awards. There will be (1)             shares of our common stock authorized for issuance under the 2014 equity incentive plan plus (2)             shares of our common stock represented by awards granted under our 2001 equity incentive plan that are forfeited, expire or are cancelled without delivery of shares or which result in the forfeiture of shares of our common stock back to us on or after the date that the 2014 equity incentive plan becomes effective.

In addition, the 2014 equity incentive plan contains an “evergreen” provision, which allows for an annual increase in the number of shares of our common stock available for issuance under the 2014 equity incentive plan on the first day of each fiscal year during the period beginning in fiscal year 2015 and ending in fiscal year 2024. The annual increase in the number of shares shall be equal to the lowest of:

•             shares of our common stock;

•     % of the number of shares of our common stock outstanding as of such date; and

• an amount determined by our board of directors or compensation committee.

The board of directors has authorized our compensation committee to administer the 2014 equity incentive plan. In accordance with the provisions of the plan, the compensation committee will determine the terms of options and other awards. The compensation committee or our board of directors will determine:

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• which employees, directors and consultants shall be granted awards;

• the number of shares of our common stock subject to options and other awards;

• the exercise price of each option, which generally shall not be less than fair market value on the date of grant;

• the schedule upon which options become exercisable;

• the termination or cancellation provisions applicable to options;

• the terms and conditions of other awards, including conditions for repurchase, termination or cancellation, issue price and repurchase price; and

• all other terms and conditions upon which each award may be granted in accordance with our plan.

No participant may receive awards for more than             shares of our common stock in any fiscal year.

In addition, our board of directors or any committee to which the board of directors delegates authority may, with the consent of the affected plan participants, re-price or otherwise amend outstanding awards consistent with the terms of our plan.

Upon a merger, consolidation or sale of all or substantially all of our assets, our board of directors or any committee to which the board of directors delegates authority, or the board of directors of any corporation assuming our obligations, may, in its sole discretion, take any one or more of the following actions pursuant to our plan, as to some or all outstanding awards, to the extent not otherwise agreed under any individual optionholder’s option or employment agreement:

• provide that outstanding options will be assumed or substituted for options of the successor corporation;

• provide that the outstanding options must be exercised within a certain number of days, either to the extent the options are then exercisable, or at our board of directors’ discretion, any such options being made partially or fully exercisable;

• terminate outstanding options in exchange for a cash payment of an amount equal to the difference between (a) the consideration payable upon consummation of the corporate transaction to a holder of the number of shares into which such option would have been exercisable to the extent then exercisable (or, in our board of directors’ discretion, any such options being made partially or fully exercisable) and (b) the aggregate exercise price of those options;

• provide that outstanding stock grants will be substituted for shares of the successor corporation or consideration payable with respect to our outstanding stock in connection with the corporate transaction; and

• terminate outstanding stock grants in exchange for payment of an amount equal to the consideration payable upon consummation of the corporate transaction to a holder of the same number of shares comprising the stock grant, to the extent the stock grant is no longer subject to any forfeiture or repurchase rights (or, at our board of directors’ discretion, all forfeiture and repurchase rights being waived upon the corporate transaction).

2001 Equity Incentive Plan

The 2001 equity incentive plan, as amended, or the 2001 equity incentive plan, was adopted in May 2001 and was last amended in December 2013. As of December 31, 2013, a maximum of 82,828,526 shares of our common stock was authorized for issuance under the 2001 equity incentive plan. The 2001 equity incentive plan allows us to grant options, restricted stock awards and other stock-based awards to our employees, officers and directors as well as outside consultants we retain from time to time. As of December 31, 2013, under the 2001

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equity incentive plan, options to purchase 80,198,540 shares of our common stock were outstanding, 15,859 shares of our common stock had been issued and were outstanding pursuant to the exercise of options, and 2,614,127 shares of our common stock were available for future awards. We anticipate that in connection with the completion of this offering we will terminate the 2001 equity incentive plan.

Under the 2001 equity incentive plan, if we are consolidated with or acquired by another entity in a merger, sale of all or substantially all of our assets or otherwise, our board of directors or the board of directors of any entity assuming our obligations under the 2001 equity incentive plan will take any of the following actions with respect to some or all of the options, to the extent not otherwise agreed under any individual optionholder’s option or employment agreement: (i) provide that outstanding options will be substituted on equitable basis for the shares subject to such options either with (a) consideration payable with respect to the outstanding shares in connection with the acquisition event or (b) with comparable securities of the surviving corporation or acquiring entity; (ii) provide option holders with an opportunity upon written notice to exercise their outstanding options within a specific number of days, after which the options will terminate; or (iii) require that option holders surrender their outstanding options in exchange for a payment in cash in an amount equal to the amount by which the then fair market value of the unexercised options exceeds the exercise price of the options.

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CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS

Since January 1, 2011, we have engaged in the following transactions with our directors, executive officers and holders of more than 5% of our voting securities, which we refer to as our principal stockholders, and affiliates or immediately family members of our directors, executive officers and principal stockholders. We believe that all of these transactions were on terms as favorable as could have been obtained from unrelated third parties.

Some of our directors are or were recently affiliated with our principal stockholders as indicated in the table below:

Director	Affiliation with Principal Stockholder
P. Ramsay Battin	Consultant to Arcapita Investment Management US Inc., an investment adviser to Arcapita Ventures I Limited and a former director of Arcapita Inc., an affiliate of Arcapita Ventures I Limited.
Craig A. Huff	Senior Managing Member of RCGM, LLC, the ultimate general partner of Reservoir Capital Partners, L.P. and Reservoir Capital Master Fund, L.P.
Steven R. Mitchell	Managing Director of Argonaut Private Equity, LLC, the former manager of GKFF Ventures I, LLC (formerly known as Argonaut Ventures I, LLC) until January 2013.
David J. Prend	Managing Member of the general partners of RockPort Capital Partners, L.P. and affiliated entities.

See “— Agreements with Stockholders” for a discussion of arrangements among our stockholders pursuant to which our directors were selected.

Convertible Note and Warrant Financings

June 2011 Convertible Note Financing

In June 2011, we entered into a note purchase agreement pursuant to which, on June 1, 2011 and June 14, 2011, we issued $26.0 million and $4.0 million, respectively, in aggregate principal amount of subordinated convertible promissory notes, which we refer to as the June 2011 convertible notes. We refer to the issuance of the June 2011 convertible notes as the June 2011 convertible note financing. Certain of the June 2011 convertible notes were purchased by certain of our principal stockholders in the following amounts and on the following dates:

Name of Beneficial Owner	Original Principal Amount of June 2011 Convertible Notes Issued on June 1, 2011		Original Principal Amount of June 2011 Convertible Notes Issued on June 14, 2011		Total Original Principal Amount of June 2011 Convertible Notes
Entities affiliated with Fidelity Investments	$	25,000,000	$	4,000,000	$	29,000,000

Interest on the June 2011 convertible notes accrues at the rate of 8.0% per year. The unpaid principal amount of the June 2011 convertible notes, together with all interest accrued but unpaid thereon, will be automatically converted into common stock upon the closing of the offering made hereby at a conversion price equal to 62.5% of the price to the public in this offering. Assuming an initial public offering price of $        per share, the mid-point of the price range set forth on the cover page of this prospectus, and the closing of the offering made hereby occurs on                    , 2014, the $30.0 million principal amount of the outstanding June 2011 convertible notes and interest thereon will convert into approximately            shares of our common stock.

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In addition, we reimbursed entities affiliated with Fidelity Investments an aggregate of $30,000 for expenses incurred by them in connection with the June 2011 convertible note financing.

The holders of the June 2011 convertible notes will be entitled to the registration rights provided in the sixth amended and restated registration rights agreement, as amended, with regard to the shares of common stock issued upon the automatic conversion of the June 2011 convertible notes.

December 2011 Convertible Note Financing

In December 2011, we entered into a note purchase agreement pursuant to which, on December 6, 2011 and March 1, 2012, we issued $15.0 million and $0.8 million, respectively, in aggregate principal amount of subordinated convertible promissory notes, which we refer to as the December 2011 convertible notes. We refer to the issuance of the December 2011 convertible notes as the December 2011 convertible note financing. Certain of the December 2011 convertible notes were purchased by certain of our principal stockholders, directors and executive officers in the following amounts and on the following dates:

Name of Beneficial Owner	Original Principal Amount of December 2011 Convertible Notes Issued on December 6, 2011		Original Principal Amount of December 2011 Convertible Notes Issued on March 1, 2012		Total Original Principal Amount of December 2011 Convertible Notes
Arcapita Ventures I Limited(1)	$	579,150		—	$	579,150
GKFF Ventures I, LLC (formerly Argonaut Ventures I, LLC)	$	677,972		—	$	677,972
Entities affiliated with Fidelity Investments	$	6,000,000		—	$	6,000,000
Reservoir Capital Partners, L.P. and affiliated funds	$	1,018,179		—	$	1,018,179
RockPort Capital Partners, L.P. and affiliated funds	$	500,255		—	$	500,255
Tenaya Capital and affiliated funds	$	224,443		—	$	224,443
P. Ramsay Battin		—	$	1,133	$	1,133
Donald R. Young		—	$	570	$	570
John F. Fairbanks		—	$	570	$	570

(1) Due to the investment restrictions of Arcapita Ventures I Limited, this note is noninterest bearing and does not automatically convert into shares of our common stock, but the holder will purchase immediately prior to this offering a number shares based on the initial public offering price and a discount factor that will result in the holder receiving approximately the number of shares that such holder would have received as if this note was automatically converted upon the same terms as the December 2011 convertible notes, including as if the notes accrued interest at the rate of 8.0% per year and converted at a conversion price equal to 62.5% of the price to public in this offering, in which event this note will then be cancelled. Because of this similar result, for simplicity we include this note in our reference to the December 2011 convertible notes even though these notes are technically not convertible. Assuming a closing date of                     , 2014, the discount factor for the note issued to Arcapita Ventures I Limited on December 6, 2011 will be             .

Interest on the December 2011 convertible notes accrues at the rate of 8.0% per year. The unpaid principal amount of the December 2011 convertible notes, together with all interest accrued but unpaid thereon, will be automatically converted into common stock upon the closing of this offering at a conversion price equal to 62.5% of the price to the public in this offering. Assuming an initial public offering price of $        per share, the mid-point of the price range set forth on the cover page of this prospectus, and the closing of the offering made hereby occurs on                    , 2014, the $15.8 million principal amount of the outstanding December 2011 convertible notes and interest thereon will convert into approximately shares of our common stock.

The holders of the December 2011 convertible notes will be entitled to the registration rights provided in the sixth amended and restated registration rights agreement, as amended, with regard to the shares of common stock issued upon the automatic conversion of the December 2011 convertible notes.

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June 2012 Convertible Note Financing

In June 2012, we entered into a note purchase agreement pursuant to which, on June 11, 2012, July 17, 2012, September 26, 2012, October 5, 2012, November 28, 2012 and January 9, 2013, we issued $9.6 million, $0.5 million, $9.5 million, $0.5 million, $4.0 million and $3.5 million, respectively, in aggregate principal amount of subordinated convertible promissory notes, which we refer to as the June 2012 convertible notes. We refer to the issuance of the June 2012 convertible notes as the June 2012 convertible note financing. Certain of the June 2012 convertible notes were purchased by certain of our principal stockholders, directors and executive officers in the following amounts and on the following dates:

Name of Beneficial Owner	Original Principal Amount of June 2012 Convertible Notes Issued on June 11, 2012		Original Principal Amount of June 2012 Convertible Notes Issued on July 17, 2012		Original Principal Amount of June 2012 Convertible Notes Issued on September 26, 2012		Original Principal Amount of June 2012 Convertible Notes Issued on October 5, 2012		Original Principal Amount of June 2012 Convertible Notes Issued on November 28, 2012		Original Principal Amount of June 2012 Convertible Notes Issued on January 9, 2013		Total Original Principal Amount of June 2012 Convertible Notes
Arcapita Ventures I Limited(1)	$	966,182		—	$	1,933,626		—		—	$	1,440,289	$	4,340,097
GKFF Ventures I, LLC (formerly Argonaut Ventures I, LLC)		1,247,960		—	$	2,533,298		—	$	2,000,000		—	$	5,781,258
Entities affiliated with Fidelity Investments	$	2,000,000		—		—		—		—		—	$	2,000,000
Reservoir Capital Partners, L.P. and affiliated funds	$	1,862,418		—	$	3,764,561		—	$	2,000,000	$	794,831	$	8,421,810
RockPort Capital Partners, L.P. and affiliated funds	$	514,175		—	$	1,026,583		—		—		—	$	1,540,758
Tenaya Capital and affiliated funds	$	409,264		—	$	251,295	$	490,637		—	$	571,781	$	1,722,977
P. Ramsay Battin		—	$	1,896		—		—		—	$	942	$	2,838
Donald R. Young		—	$	1,000		—		—		—	$	497	$	1,497
John F. Fairbanks		—	$	1,000		—		—		—	$	497	$	1,497

(1) Due to the investment restrictions of Arcapita Ventures I Limited, these notes are noninterest bearing and do not automatically convert into shares of our common stock, but the holder will purchase immediately prior to this offering a number shares based on the initial public offering price and a discount factor that will result in the holder receiving approximately the number of shares that such holder would have received as if these notes were automatically converted upon the same terms as the June 2012 convertible notes, including as if the notes accrued interest at the rate of 8.0% per year and converted at a conversion price equal to 62.5% of the price to public in this offering, in which event these notes will then be cancelled. Because of this similar result, for simplicity we include these notes in our reference to the June 2012 convertible notes even though these notes are technically not convertible. Assuming a closing date of                     , 2014, the discount factors for the notes issued to Arcapita Ventures I Limited on June 11, 2012 and September 26, 2012 will be                      and                     , respectively. The note issued to Arcapita Ventures I Limited on January 9, 2013 is no longer outstanding.

Interest on the June 2012 convertible notes accrues at the rate of 8.0% per year. The unpaid principal amount of the June 2012 convertible notes, together with all interest accrued but unpaid thereon, will be automatically converted into common stock upon the closing of the offering made hereby at a conversion price equal to 62.5% of the price to the public in this offering. The June 2012 convertible notes that were issued in November 2012 and January 2013 were cancelled in exchange for certain March 2013 convertible notes discussed below under “— 2013 Convertible Note and Warrant Financing.” Assuming an initial public offering

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price of $        per share, the mid-point of the price range set forth on the cover page of this prospectus, and the closing of the offering made hereby occurs on                    , 2014, the $20.1 million principal amount of the outstanding June 2012 convertible notes and interest thereon will convert into approximately            shares of our common stock.

The holders of the June 2012 convertible notes will be entitled to the registration rights provided in the sixth amended and restated registration rights agreement, as amended, with regard to the shares of common stock issued upon the automatic conversion of the June 2012 convertible notes.

2013 Convertible Note and Warrant Financing

In March 2013, we entered into a note and warrant purchase agreement pursuant to which, on March 28, 2013 and May 6, 2013, we issued $12.0 million and $10.5 million, respectively, in aggregate principal amount of senior subordinated convertible promissory notes, which we refer to as the March 2013 convertible notes. The March 2013 convertible notes were purchased from the Company for an aggregate of $15.0 million of cash and in exchange for an aggregate of $7.5 million in principal amount of certain of our June 2012 convertible notes issued in November 2012 and January 2013. Certain of the March 2013 convertible notes were purchased by certain of our principal stockholders, directors and executive officers in the following amounts and on the following dates:

Name of Beneficial Owner	Original Principal Amount of March 2013 Convertible Notes Issued on March 28, 2013			Original Principal Amount of March 2013 Convertible Notes Issued on May 6, 2013			Total Original Principal Amount of March 2013 Convertible Notes Issued
Arcapita Ventures I Limited(1)	$	1,440,289	(2)	$	1,535,862	(3)	$	2,976,151
GKFF Ventures I, LLC (formerly known as Argonaut Ventures I, LLC)	$	4,500,000	(4)	$	1,856,279	(3)	$	6,356,279
Entities affiliated with Fidelity Investments		—		$	496,684	(3)	$	496,684
Reservoir Capital Partners, L.P. and affiliated funds	$	5,294,831	(5)	$	2,246,670	(3)	$	7,541,501
RockPort Capital Partners, L.P. and affiliated funds		—		$	1,569,056	(3)	$	1,569,056
Tenaya Capital and affiliated funds	$	571,781	(3)		—		$	571,781
P. Ramsay Battin		—		$	5,942	(6)	$	5,942
Donald R. Young		—		$	1,319	(7)	$	1,319
John F. Fairbanks		—		$	1,319	(7)	$	1,319

(1) Due to the investment restrictions of Arcapita Ventures I Limited, these notes are noninterest bearing and do not automatically convert into shares of our common stock, but the holder will purchase immediately prior to this offering a number shares based on the initial public offering price and a discount factor that will result in the holder receiving approximately the number of shares that such holder would have received as if this note was automatically converted upon the same terms as the March 2013 convertible notes, including as if the notes accrued interest at the rate of 8.0% per year and converted at a conversion price equal to 62.5% of the price to public in this offering, in which event these notes will then be cancelled. Because of this similar result, for simplicity we include these notes in our reference to the March 2013 convertible notes even though these notes are technically not convertible. Assuming a closing date of                     , 2014, the discount factors for the notes issued to Arcapita Ventures I Limited on March 28, 2013 and May 6, 2013 will be                      and                     , respectively.

(2) This note was purchased by exchange of a note previously issued by the Company.

(3) These notes were purchased for cash.

(4) These convertible notes were purchased for $2.5 million in cash and the exchange of $2.0 million in principal amount of June 2012 convertible notes previously issued by the Company and interest thereon.

(5) These convertible notes were purchased for $2.5 million in cash and the exchange of $2.8 million in principal amount of June 2012 convertible notes previously issued by the Company and interest thereon.

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(6) These convertible notes were purchased for $5,000 in cash and the exchange of $942 in principal amount of June 2012 convertible notes previously issued by the Company and interest thereon.

(7) These convertible notes were each purchased for $822 in cash and the exchange of $497 in principal amount of June 2012 convertible notes previously issued by the Company and interest thereon.

Interest on the March 2013 convertible notes accrues at the rate of 8.0% per year. The unpaid principal amount of the March 2013 convertible notes, together with any interest accrued but unpaid thereon, will be automatically converted into common stock upon the closing of the offering made hereby at a conversion price equal to 62.5% of the price to the public in this offering. Assuming an initial public offering price of $        per share, the mid-point of the price range set forth on the cover page of this prospectus, and the closing of the offering made hereby occurs on                    , 2014, the $22.5 million principal amount of the outstanding March 2013 convertible notes and interest thereon will convert into approximately            shares of our common stock. In addition, we reimbursed GKFF Ventures I, LLC an aggregate of approximately $247,000 for expenses incurred by them in connection with the March 2013 note and warrant financing.

In connection with March 2013 convertible note financing, we issued warrants to purchase an aggregate of 87,018,187 shares of our Series C preferred stock, which we refer to as the Series C warrants, to the purchasers of our March 2013 convertible notes for no additional consideration. We refer to the issuance of the March 2013 convertible notes and the Series C warrants as the March 2013 convertible note and warrant financing. The warrants are exercisable at a price of $0.0001 per share and remain exercisable until March 28, 2023. Warrants to purchase 20,000 shares of Series C preferred stock have been exercised as of April 15, 2014, and we anticipate that the remainder of these warrants will be exercised in connection with this offering, which together with the previously exercised Series C warrants, will result in the issuance of 87,018,187 shares of our common stock following the conversion of our Series C preferred stock into common stock in connection with this offering. Certain of these warrants were acquired by our principal stockholders, directors and executive officers in the following amounts and on the following dates:

Name of Beneficial Owner	Warrants to Purchase Series C Preferred Stock Issued on March 28, 2013		Warrants to Purchase Series C Preferred Stock Issued on May 6, 2013		Total Warrants to Purchase Series C Preferred Stock
Arcapita Ventures I Limited		5,570,280		5,939,906		11,510,186
GKFF Ventures I, LLC (formerly known as Argonaut Ventures I, LLC)		17,403,634		7,179,110		24,582,744
Entities affiliated with Fidelity Investments		—		1,920,915		1,920,915
Reservoir Capital Partners, L.P. and affiliated funds		20,477,623		8,688,939		29,166,562
RockPort Capital Partners, L.P. and affiliated funds		—		6,068,285		6,068,285
Tenaya Capital and affiliated funds		2,211,349		—		2,211,349
P. Ramsay Battin		—		22,981		22,981
Donald R. Young		—		5,100		5,100
John F. Fairbanks		—		5,100		5,100

The holders of the March 2013 convertible notes and Series C warrants will be entitled to the registration rights provided in the sixth amended and restated registration rights agreement, as amended, with regard to the shares of common stock issued upon the automatic conversion of the March 2013 convertible notes and the exercise of the Series C warrants.

Agreements with Stockholders

In connection with the 2013 convertible note and warrant financing described above under “— Convertible Note and Warrant Financings — 2013 Convertible Note and Warrant Financing,” we entered into various stockholder agreements with our security holders relating to voting rights, information rights and registration rights, among other things. Our Sixth Amended and Restated Stockholders’ Agreement dated March 28, 2013 requires the stockholders party thereto to vote to elect to our board of directors up to two individuals designated

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by GKFF Ventures I, LLC, of which currently solely Steven R. Mitchell has been designated; up to two individuals designated by Reservoir Capital Partners, L.P. and affiliated funds, of which currently solely Craig A. Huff has been designated; one individual designated by Arcapita Ventures I Limited, currently P. Ramsay Battin; one individual designated by RockPort Capital, currently David J. Prend; up to two individuals designated by holders of our Series C preferred stock, none of which have yet been designated; and one individual who is our Chief Executive Officer, currently Donald R. Young. Therefore, currently GKFF Ventures I, LLC and Reservoir Capital Partners, L.P. (and affiliated funds) each have the right to designate one additional individual and the holders of our Series C preferred stock have the right to designate two additional individuals. The voting and information rights under these stockholder agreements will terminate upon the completion of this offering.

Indemnification Agreements

We have entered into indemnification agreements with each of our non-employee directors and will enter into similar agreements with certain officers. The indemnification agreements and our restated certificate of incorporation and restated by-laws require us to indemnify our directors and officers to the fullest extent permitted by Delaware law. See “Management — Limitation of Directors’ and Officers’ Liability and Indemnification.”

Registration Rights

Following the expiration of the lock-up period described below in “Shares Eligible for Future Sale — Lock-Up Agreements,” pursuant to our registration rights agreement, the holders of                  shares of common stock, which includes 2,604,460 shares of common stock outstanding as of April 15, 2014, 96,333,792 shares of common stock issuable upon conversion of all of our outstanding preferred stock (including the conversion of the shares of Series C preferred stock to be issued upon the assumed exercise of our Series C warrants upon the consummation of this offering),            shares of our common stock issuable upon conversion of our convertible notes upon completion of the offering made hereby (including the shares of our common stock to be purchased in connection with the offering made hereby by Arcapita Ventures I Limited in exchange for the cancellation of outstanding notes it holds) and 99,354 shares of common stock issuable pursuant to the exercise of warrants or their transferees, are entitled to registration rights with respect to the shares of common stock held by them. These shares include substantially all of the shares held following this offering by our principal stockholders and their affiliates and the shares held following this offering upon conversion of the preferred stock and convertible notes held by P. Ramsay Battin, one of our directors; Donald R. Young, our President, Chief Executive Officer and one of our directors; and John F. Fairbanks, our Vice President, Chief Financial Officer and Treasurer.

See “Description of Capital Stock — Registration Rights” for a more detailed description of these registration rights.

Policy for Approval of Related Person Transactions

Pursuant to the written charter of our audit committee that will be in effect upon completion of this offering, the audit committee is responsible for reviewing, discussing with management and the independent auditors and approving, (i) prior to our entry into any such transaction, all transactions in which we are a participant and in which any parties related to us, including our executive officers, our directors, beneficial owners of more than 5% of our securities, immediate family members of the foregoing persons and any other persons whom our board of directors determines may be considered related parties under Item 404 of Regulation S-K, has or will have a direct or indirect material interest, or (ii) courses of dealing with related parties that are significant in size or involve terms or other aspects that differ from those that would likely be negotiated with independent parties. Approval of such related party transaction may, at the discretion of our audit committee, be conditioned upon our and/or the related person at issue taking any actions that our audit committee in its judgment determines to be necessary or appropriate. In the event that a member of our audit committee has an interest in the related party transaction under discussion, such member must abstain from voting on the transaction. Such member may, if so requested by the chair of the audit committee, participate in some or all of the discussions about the related party transaction in question.

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PRINCIPAL STOCKHOLDERS

The following table and accompanying footnotes present information about the beneficial ownership of our common stock as of April 15, 2014, and as adjusted to reflect the shares offered by this prospectus, by:

• each existing stockholder we know to beneficially own 5% or more of our common stock after this offering, which we call our principal stockholders;

• each of our directors and director nominees;

• each of our named executive officers; and

• all of our current directors and director nominees and executive officers as a group.

Beneficial ownership is determined in accordance with the rules of the SEC and includes voting or investment power with respect to the securities. Shares of common stock that may be acquired by an individual or group within 60 days following April 15, 2014, pursuant to the exercise of options or warrants are deemed to be outstanding for the purpose of computing the percentage ownership of such individual or group, but are not deemed to be outstanding for the purpose of computing the percentage ownership of any other person shown in the table. Under these rules, more than one person may be deemed to be a beneficial owner of the same securities and a person may be deemed to be a beneficial owner of securities as to which such person has no economic interest.

The percentage of shares beneficially owned before the offering is based on 98,982,596 shares of our common stock outstanding as of April 15, 2014, which gives effect to the automatic conversion of all shares of our preferred stock outstanding at April 15, 2014 into an aggregate of 96,333,792 shares of our common stock upon completion of the offering made hereby, assuming the exercise for cash of all of our outstanding warrants to purchase Series C preferred stock immediately prior thereto, but does not give effect to (i) the automatic conversion of our convertible notes, including accrued but unpaid interest thereon, upon the completion of the offering made hereby into an aggregate of              shares of our common stock, at a conversion price equal to 62.5% of the initial offering price, or (ii) the purchase of the aggregate of              shares of our common stock upon completion of the offering made hereby in exchange for the cancellation of our non-interest bearing promissory notes issued to Arcapita Ventures I Limited at a discount rate that would result in the holder receiving an amount of shares of common stock equivalent to a convertible note that bore interest at the same 8% interest rate and converted at the same 62.5% conversion price as our convertible notes, in each case, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014. This information will be adjusted when a price range is determined. The percentage of shares beneficially owned before the offering also assumes, for purposes of calculating the beneficial ownership of certain holders of options to purchase shares of our common stock as set forth in the prior paragraph, that the offering made hereby has not occurred. The percentage of shares beneficially owned after the offering is based on              shares of our common stock to be outstanding after the offering, assuming an initial public offering price of $         per share, the midpoint of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                 , 2014.

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Except as indicated in footnotes to this table, we believe that the stockholders named in this table have sole voting and investment power with respect to all shares of common stock shown to be beneficially owned by them, based on information provided to us by such stockholders. Unless otherwise indicated, the address of all listed stockholders is c/o Aspen Aerogels, 30 Forbes Road, Building B, Northborough, Massachusetts 01532.

	Prior to this Offering					After this Offering
	Shares of Common Stock		Percentage of Common Stock			Shares of Common Stock	Percentage of Common Stock
Name of Beneficial Owner
Principal Stockholders:
Arcapita Ventures I Limited(1)		13,389,116		13.5	%
GKFF Ventures I, LLC (formerly known as Argonaut Ventures I, LLC)(2)		26,870,639		27.1	%
Reservoir Capital Partners, L.P. and affiliated funds(3)		32,364,977		32.7	%
RockPort Capital Partners, L.P. and affiliated funds(4)		7,652,971		7.7	%
Tenaya Capital and affiliated funds(5)		2,890,696		2.9	%
Entities affiliated with Fidelity Investments(6)		1,920,915		1.9	%
Directors and Named Executive Officers:
Donald R. Young(7)		3,572,219		3.5	%
John F. Fairbanks(8)		849,107		*
Corby C. Whitaker(9)		561,393		*
P. Ramsay Battin(10)		26,792		*
Robert M. Gervis(11)		242,237		*
Craig A. Huff(12)		32,364,977		32.7	%
Steven R. Mitchell(13)		—		*
Mark L. Noetzel(14)		287,569		*
David J. Prend(15)		7,652,971		7.7	%
Richard F. Reilly(16)		249,320		*
All executive officers and directors as a group (12 persons)(17)		46,789,023		44.3	%

* Indicates beneficial ownership of less than 1%.

(1) Consists of (i) 13,389,116 shares held by Arcapita Ventures I Limited (“AVIL”), including 11,510,186 shares of our common stock to be issued upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of warrants to purchase Series C preferred stock, and (ii)              shares of our common stock to be issued in connection with purchases in exchange for the cancellation of $6.5 million principal amount of promissory notes upon the closing of the offering made hereby, assuming an initial public offering price of $          per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014. AVIL is a wholly-owned subsidiary of Arcapita Ventures I Holding Company Limited (“Arcapita Holding”). Arcapita Ventures I Holdings Limited, VCI Angel Capital Limited, VCI Corporate Capital Limited, VCI Enterprise Capital Limited, VCI Investment Capital Limited, VCI Transaction Capital Limited and AIPL Subsidiary Limited are the voting shareholders (the “Arcapita Shareholders”) of Arcapita Holding, and therefore share voting and investment control over the securities held by AVIL. The address for AVIL is c/o Arcapita Investment Management US Inc., 75 Fourteenth Street, 23rd Floor, Atlanta, Georgia 30309.

(2) Consists of (i) 26,870,639 shares held by GKFF Ventures I, LLC (formerly known as Argonaut Ventures I, LLC) (“GKFF Ventures”), including 24,572,744 shares of our common stock to be issued upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of warrants to purchase Series C preferred stock, and (ii)              shares of our common stock to be issued to GKFF Ventures upon the automatic conversion of $10.8 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made

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hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $          per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014. GKFF Ventures is managed by Ken Levit and Robert Thomas. George Kaiser Family Foundation (“GKFF”) is the sole equity owner of GKFF Ventures. Messrs. Levit and Thomas and GKFF may be deemed to share and voting and investment control over the shares, which are beneficially owned by GKFF Ventures. Each of these individuals and GKFF disclaims beneficial ownership of the reported securities except to the extent of his or its pecuniary interest therein. The address of GKFF Ventures I, LLC is c/o George Kaiser Family Foundation, 7030 South Yale Avenue, Suite 600, Tulsa, Oklahoma 74136.

(3) Consists of (i) 32,364,977 shares held by Reservoir Capital Partners, L.P. (“RCP”) and Reservoir Capital Master Fund, L.P. (“RCMF”), including 26,582,438 shares and 2,574,124 shares of our common stock to be issued to RCP and RCMF, respectively, upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of the warrants to purchase Series C preferred stock, (ii) warrants to purchase 270 shares and 37 shares of our common stock held by RCP and RCMF, respectively, which are exercisable within 60 days following April 15, 2014, and (iii)              shares of our common stock to be issued upon the automatic conversion of $14.2 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $          per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014, of which              shares of our common stock will be issued to RCP and shares of our common stock will be issued to RCMF. The securities held by RCP may be deemed to be beneficially owned by Daniel Stern and one of our directors, Craig A. Huff, who are the senior managing members (the “Reservoir Members”) of RCGM, LLC (“RCGM”). RCGM is the managing member of Reservoir Capital Group, L.L.C. (“RCG”), which is in turn the general partner of Reservoir Capital Partners (Cayman), L.P. (“RCP Cayman”), which is in turn the sole member of RCP GP, LLC (“RCP GP”), and which is in turn the general partner of RCP. The securities held by RCMF may be deemed to be beneficially owned by the Reservoir Members, who are the senior managing members of RCGM. RCGM is the managing member of RCG, which is in turn the general partner of RCMF. As a result, Messrs. Stern and Huff share voting and investment control over the shares held by RCP and RCMF. Each of the Reservoir Members, RCGM, RCG, RCP Cayman and RCP GP disclaims beneficial ownership of the reported securities except to the extent of his or its pecuniary interest therein. The address for RCP and RCMF is c/o Reservoir Capital Group, L.L.C., 650 Madison Avenue, 24^th Floor, New York, New York 10022.

(4) Consists of (i) 7,652,971 shares held by RockPort Capital Partners, L.P. (“RockPort I”), RockPort Capital Partners II, L.P. (“RockPort II”), RockPort SII, LLC (“RSII”) and RP Co-Investment Fund I, LP (“RPCIF”), including 3,093,980 shares, 1,933,737 shares, 831,647 shares and 208,921 shares of our common stock to be issued to RockPort I, RockPort II, RSII and RPCIF, respectively, upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of the warrants to purchase Series C preferred stock, (ii) warrants to purchase 1,397 shares, 137 shares, 45 shares and 10 shares of our common stock held by RockPort I, RockPort II, RSII and RPCIF, respectively, which are exercisable within 60 days following April 15, 2014, and (iii)              shares of our common stock to be issued upon the automatic conversion of $3.6 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014, of which              shares of our common stock will be issued to RockPort I,              shares of our common stock will be issued to RockPort II,              shares of our common stock will be issued to RSII and              shares of our common stock will be issued to RPCIF. The securities held by RockPort I, RockPort II, RSII and RPCIF may be deemed to be beneficially owned by RockPort Capital I, LLC, RockPort Capital II, LLC, RockPort SGII, LLC and RP Co-Investment Fund I GP, LLC, respectively, each of which is the general partner of the respective entity. The securities held by RockPort I, RockPort II, RSII and RPCIF may also be deemed to be beneficially owned by

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Alexander Ellis III, Janet B. James, William E. James, Charles J. McDermott, Stoddard M. Wilson and one of our directors, David J. Prend, who are the managing members (the “Rockport Members”) of the general partners of each of RockPort I, RockPort II, RSII and RPCIF, all of which may be deemed to share voting and investment control with respect to such shares. Each of the general partners of RockPort I, RockPort II, RSII and RPCIF and the Rockport Members (the “Rockport Reporting Persons”) disclaim beneficial ownership of the reported securities except to the extent of his, her or its pecuniary interest therein. The address for the Rockport Reporting Persons is c/o RockPort Capital Partners, 160 Federal Street, 18th Floor, Boston, Massachusetts 02110.

(5) Consists of (i) 2,890,696 shares of our common stock held by Tenaya Capital IV, LP (“TC IV”), Tenaya Capital IV-C, LP (“TC IV-C”) and Tenaya Capital IV-P, LP (“TC IV-P”), including 749,009 shares, 716,085 shares and 746,255 shares of our common stock to be issued to TC IV, TC IV-C and TC IV-P, respectively, upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of the warrants to purchase Series C preferred stock, (ii) warrants to purchase 67 shares, 63 shares and 66 shares of our common stock held by TC IV, TC IV-C and TC IV-P, respectively, which are exercisable within 60 days following April 15, 2014, and (iii)              shares of our common stock to be issued upon the automatic conversion of $1.9 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $             per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014, of which              shares of our common stock will be issued to TC IV,              shares of our common stock will be issued to TC IV-C and              shares of our common stock will be issued to TC IV-P. The general partner of TC IV is Tenaya Capital IV Annex GP, LLC (“TC IV Annex”). The general partner of both TC IV-P and TC IV-C is Tenaya Capital IV GP, LP, whose general partner is Tenaya Capital IV GP, LLC (“TC IV LLC”). The managing members of TC IV LLC and TC IV Annex are Thomas E. Banahan, Benjamin Boyer, Stewart Gollmer, Brian Melton and Brian Paul (collectively, the “TC Managing Members”), all of whom share voting and dispositive power over these shares. The TC Managing Members disclaim beneficial interest in such shares except to the extent of their respective pecuniary interests therein, if any. The address for TC IV, TC IV-P, TC IV-C and the TC Managing Members is c/o Tenaya Capital, 3280 Alpine Road, Portola Valley, California 94028.

(6) Consists of 1,920,915 shares of our common stock to be issued upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of the warrants to purchase Series C preferred stock, of which 349,991 shares will be issued to Fidelity Advisor Series VII: Fidelity Advisor Industrials Fund, 763,947 shares will be issued to Fidelity Central Investment Portfolios LLC: Fidelity Industrials Central Fund, 262,973 shares will be issued to Fidelity Central Investment Portfolios LLC: Fidelity Materials Central Fund, 461,788 shares will be issued to Fidelity Select Portfolios: Industrials Portfolio and 82,216 shares will be issued to Variable Insurance Products Fund IV: Industrials Portfolio, and also consists of              shares of our common stock to be issued upon the automatic conversion of $37.5 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $          per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014, of which              shares of our common stock will be issued to Fidelity Advisor Series I: Fidelity Advisor Dividend Growth Fund,              shares of our common stock will be issued to Fidelity Advisor Series VII: Fidelity Advisor Industrials Fund,              shares of our common stock will be issued to Fidelity Central Investment Portfolios LLC: Fidelity Industrials Central Fund,              shares of our common stock will be issued to Fidelity Central Investment Portfolios LLC: Fidelity Materials Central Fund,              shares of our common stock will be issued to Fidelity Puritan Trust: Fidelity Puritan Fund,              shares of our common stock will be issued to Fidelity Securities Fund: Fidelity Dividend Growth Fund,              shares of our common stock will be issued to Fidelity Select Portfolios: Environment and Alternative Energy Portfolio,              shares of our common stock will be issued to Fidelity Select Portfolios: Industrials Portfolio,              shares of our common stock will be issued to Fidelity Select Portfolios: Materials,              shares of our common stock will be issued to Variable Insurance Products Fund III: Balanced Portfolio,              shares of our common stock will be issued to Variable Insurance Products Fund IV: Industrials Portfolio,

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and              shares of our common stock will be issued to Variable Insurance Products Fund IV: Materials Portfolio. Fidelity Management & Research Company, or Fidelity, 245 Summer Street, F7B, Boston, Massachusetts 02210, a wholly-owned subsidiary of FMR LLC and an investment adviser registered under Section 203 of the Investment Advisers Act of 1940, is the beneficial owner of the securities held by these funds as a result of acting as investment adviser to various investment companies registered under Section 8 of the Investment Company Act of 1940. Edward C. Johnson 3d and FMR LLC, through its control of Fidelity, and the funds each has sole power to dispose of the securities owned by the Funds. Members of the family of Edward C. Johnson 3d, Chairman of FMR LLC, are the predominant owners, directly or through trusts, of Series B voting common shares of FMR LLC, representing 49% of the voting power of FMR LLC. The Johnson family group and all other Series B shareholders have entered into a shareholders’ voting agreement under which all Series B voting common shares will be voted in accordance with the majority vote of Series B voting common shares. Accordingly, through their ownership of voting common shares and the execution of the shareholders’ voting agreement, members of the Johnson family may be deemed, under the Investment Company Act of 1940, to form a controlling group with respect to FMR LLC. Neither FMR LLC nor Edward C. Johnson 3d, Chairman of FMR LLC, has the sole power to vote or direct the voting of the shares owned directly by the Fidelity Funds, which power resides with the Funds’ Boards of Trustees. Fidelity carries out the voting of the shares under written guidelines established by the Funds’ Boards of Trustees.

(7) Consists of (i) 7,017 shares held by Mr. Young, including 5,100 shares of our common stock to be issued upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of warrants to purchase Series C preferred stock, (ii) 3,565,202 shares of our common stock issuable upon the exercise of options exercisable within 60 days following April 15, 2014, including 616,491 shares issuable upon the exercise of options held by Mr. Young’s children, of which Mr. Young has sole voting power, and 40,000 shares issuable upon the exercise of options held by a trust for the benefit of Mr. Young’s family, of which Mr. Young has sole voting power, and (iii)              shares of our common stock to be issued upon the automatic conversion of less than $0.1 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $              per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014 held by Mr. Young, the vesting of which is contingent upon the consummation of this offering, based on such assumed offering price and closing date.

(8) Consists of (i) 7,017 shares held by Mr. Fairbanks, including 5,100 shares of our common stock to be issued upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of warrants to purchase Series C preferred stock, (ii) 842,090 shares of our common stock issuable upon the exercise of options exercisable within 60 days following April 15, 2014, and (iii)              shares of our common stock to be issued upon the automatic conversion of less than $0.1 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $          per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014, the vesting of which is contingent upon the consummation of this offering, based on such assumed offering price and closing date.

(9) Consists of shares issuable upon the exercise of options exercisable within 60 days following April 15, 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014, the vesting of which is contingent upon the consummation of this offering, based on such assumed offering price and closing date.

(10) Consists of (i) 25,859 shares held by Mr. Battin, including 22,981 shares of our common stock to be issued upon the automatic conversion of our Series C preferred stock following the exercise immediately prior to the consummation of this offering of warrants to purchase Series C preferred stock, and (ii)              shares of our common stock to be issued upon the automatic conversion of less than $0.1 million principal amount and all accrued but unpaid interest on the convertible notes upon the closing of the offering made hereby at a

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conversion price equal to 62.5% of the initial offering price, assuming an initial public offering price of $          per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014. Reflects securities beneficially owned individually by Mr. Battin. Mr. Battin is a consultant to Arcapita Investment Management US Inc., an investment adviser to Arcapita Ventures I Limited and is a former director of Arcapita Inc., an affiliate of AVIL, but is not deemed to beneficially own any of the shares held by AVIL.

(11) Consists of shares issuable upon the exercise of options exercisable within 60 days following April 15, 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014, the vesting of which is contingent upon the consummation of this offering, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014.

(12) Reflects securities beneficially owned by RCP and RCMF as set forth in footnote 3, for which Mr. Huff is a senior managing member of the ultimate general partner of both entities. Mr. Huff disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any.

(13) Excludes securities beneficially owned by GKFF Ventures as set forth in footnote 2. Mr. Mitchell is the managing director of Argonaut Private Equity, LLC (“APE”), which was formerly a manager of GKFF Ventures until January 2013, but Mr. Mitchell no longer has any voting or investment control over securities held by GKFF Ventures.

(14) Consists of shares issuable upon the exercise of options exercisable within 60 days following April 15, 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014, the vesting of which is contingent upon the consummation of this offering, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014.

(15) Reflects securities beneficially owned by Rockport Capital Partners, L.P. and affiliated funds as set forth in footnote 4, for which Mr. Prend is a managing member of the general partners of such securityholders. Mr. Prend disclaims beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any.

(16) Consists of shares issuable upon the exercise of options exercisable within 60 days following April 15, 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014, the vesting of which is contingent upon the consummation of this offering, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014.

(17) See footnotes 7 through 16. Also includes options to purchase 421,045 shares of common stock held by George L. Gould, Ph.D., our Vice President, Research and Development, which are exercisable within 60 days following April 15, 2014, and options to purchase 561,393 shares of common stock held by Kevin A. Schmidt, our Vice President, Operations, which are exercisable within 60 days following April 15, 2014. After this offering also includes options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014 held by Dr. Gould and options to purchase              shares of our common stock exercisable within 60 days of April 15, 2014 held by Mr. Schmidt, the vesting of which is contingent upon the consummation of this offering, assuming an initial public offering price of $         per share, the mid-point of the price range set forth on the cover page of this prospectus, and that the closing of the offering made hereby occurs on                     , 2014.

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DESCRIPTION OF CAPITAL STOCK

The following description of our capital stock and provisions of our restated certificate of incorporation and restated by-laws are summaries and are qualified by reference to our restated certificate of incorporation and restated by-laws that will be in effect upon the closing of the offering made hereby. Copies of these documents will be filed with the SEC as exhibits to our registration statement, of which this prospectus forms a part. The descriptions of our common stock and preferred stock reflect changes to our capital structure that will occur upon the closing of the offering made hereby.

Authorized Capitalization

Upon the closing of the offering made hereby, our authorized capital stock will consist of                  shares of our common stock, par value $0.00001 per share, and                  shares of preferred stock, par value $0.00001 per share.

As of April 15, 2014, assuming the exercise for cash of all of our outstanding warrants to purchase Series C preferred stock and after giving effect to the conversion of all outstanding shares of our preferred stock into shares of our common stock upon completion of this offering, each as described above in “Capitalization,” we would have had 98,982,596 shares of common stock outstanding held of record by 129 stockholders. Immediately following the completion of this offering made hereby, we will have                  shares of common stock outstanding (and                  shares of common stock outstanding if the underwriters exercise their option to purchase additional shares in full) and no shares of preferred stock outstanding.

Common Stock

As of April 15, 2014, we had issued and outstanding 2,648,804 shares of common stock, held by 113 stockholders of record, and there were outstanding options to purchase 80,050,105 shares of common stock and outstanding warrants to purchase 112,576 shares of common stock.

Holders of our common stock are entitled to one vote for each share held of record on all matters submitted to a vote of the stockholders, and do not have cumulative voting rights. Subject to preferences that may be applicable to any outstanding shares of preferred stock, holders of common stock are entitled to receive ratably such dividends, if any, as may be declared from time to time by our board of directors out of funds legally available for dividend payments. All outstanding shares of common stock are fully paid and nonassessable, and the shares of common stock to be issued upon completion of this offering will be fully paid and nonassessable. The holders of common stock have no preferences or rights of conversion, exchange, pre-emption or other subscription rights. There are no redemption or sinking fund provisions applicable to the common stock. In the event of any liquidation, dissolution or winding-up of our affairs, holders of common stock will be entitled to share ratably in our assets that are remaining after payment or provision for payment of all of our debts and obligations and after liquidation payments to holders of outstanding shares of preferred stock, if any.

Preferred Stock

As of April 15, 2014, we had issued and outstanding 5,284,347 shares of Series A preferred stock, held by 55 stockholders of record, 1,601,053 shares of Series B preferred stock held by 47 stockholders of record and 20,000 shares of Series C preferred stock held by two stockholders of record and warrants to purchase 86,998,187 shares of Series C preferred stock held by 50 warrant holders of record.

Upon completion of this offering, all of our outstanding shares of preferred stock will convert into an aggregate of 96,333,792 shares of our common stock, on a 1.31291262-for-1 basis for each share of our Series A preferred stock issued on August 14, 2009, on a 1.30651698-for-1 basis for each share of our Series A preferred stock issued on September 10, 2009, on a 1.30556948-for-1 basis for each share of our Series A preferred stock issued on September 14, 2009, on a 1.49755364-for-1 basis for each share of our Series B preferred stock issued on September 22, 2010, on a 1.48236116-for-1 basis for each share of our Series B preferred stock issued on October 20, 2010, and on a 1-for-1 basis for each outstanding share of our Series C preferred stock, assuming the

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exercise for cash of all of our outstanding warrants to purchase Series C preferred stock immediately prior to the consummation of this offering), into an aggregate of 96,333,792 shares of our common stock effective immediately prior to the completion of this offering.

If we issue preferred stock after the closing of the offering made hereby, such preferred stock would have priority over common stock with respect to dividends and other distributions, including the distribution of assets upon liquidation. Our board of directors has the authority, without further stockholder authorization, to issue from time to time up to                  shares of preferred stock in one or more series and to fix the terms, limitations, voting rights, relative rights and preferences and variations of each series. Although we have no present plans to issue any other shares of preferred stock, the issuance of shares of preferred stock, or the issuance of rights to purchase such shares, could decrease the amount of earnings and assets available for distribution to the holders of common stock, could adversely affect the rights and powers, including voting rights, of the common stock and could have the effect of delaying, deterring or preventing a change of control of us or an unsolicited acquisition proposal.

Stock Options

As of April 15, 2014, we had outstanding options to purchase 80,050,105 shares of our common stock at a weighted-average exercise price of $0.112 per share, of which options to purchase 9,553,017 shares were exercisable as of April 15, 2014. A portion of the option awards made in 2013 include a performance-based component. Upon the consummation of the offering made hereby, the number of shares subject to these options having a performance-based component shall be reduced such that the holder’s total option holdings shall equal a target percentage of our common stock deemed outstanding immediately prior to the offering, with a specific target percentage set for each holder of such options. Subject to and in the event of the consummation of this offering, 40% of the shares subject to the options having a performance-based component, plus an additional 1.667% of the shares for each month that occurred between August 7, 2013 and the consummation of this offering will vest upon the consummation of this offering, and 1.667% of the shares will vest in equal monthly installments each month following the consummation of this offering until 36 months following August 7, 2013. In the event of a change of control of the company, 12 months of this vesting schedule will be accelerated with respect to options issued to our employees and all of the unvested options will vest with respect to options issued to our directors. See “Executive and Director Compensation — Equity Incentive Plans” for additional information regarding our 2001 equity incentive plan and 2014 equity incentive plan.

Warrants

As of April 15, 2014, we had warrants outstanding for the number of shares of our common stock at the exercise prices and expiration dates set forth below. Warrants entitle the holder to purchase shares of our common stock at the specified exercise price at any time prior to the expiration date.

Expiration Date	Number of Shares		Weighted-Average Exercise Price
October 20, 2014 (1)(2)(3)(4)(5)		6	$	45.242
October 28, 2014 (1)(2)(3)(4)(5)		3	$	45.242
January 12, 2015 (1)(2)(3)(4)(5)		3	$	45.242
June 10, 2016		13,222	$	0.030
December 29, 2017 (3)(5)		99,342	$	0.010
Total:		112,576	$	0.017

⁽¹⁾  Each of these warrants contains anti-dilution provisions providing for adjustments to the exercise price upon the issuance of shares of our common stock at a price less than the exercise price, excluding shares of our common stock issuable upon exercise of options, warrants, conversion of convertible securities and certain issuances approved in advance by a majority of our board of directors.

⁽²⁾  Each of these warrants expires on the earlier of this date or a corporate event, which is defined in the warrant to include (i) the sale, transfer, exchange or other disposition of all or substantially all of our assets; (ii) a merger or reorganization that results in our stockholder immediately prior to such transaction holding less than 50% of the voting power of the surviving entity of such transaction; (iii) a dissolution or liquidation; and (iv) the sale, transfer, exchange or other disposition of all or substantially all of our common stock.

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⁽³⁾  The shares underlying each of these warrants are entitled to certain registration rights set forth in our registration rights agreement. See “— Registration Rights” below for a description of these registration rights.

⁽⁴⁾  Each of these warrants provides that immediately before its expiration or termination, if the fair market value of one share of our common stock is greater than the exercise price, the warrant will be automatically exercised pursuant to its net exercise provision.

⁽⁵⁾  Each of these warrants has net exercise provisions under which the holder may, in lieu of payment of the exercise price in cash, surrender the warrant and receive a net amount of shares of our common based on the fair market value of the underlying shares of our common stock at the time of exercise of the warrant, after deduction of the aggregate exercise price.

In addition, as of April 15, 2014, we had outstanding warrants to purchase 86,998,187 shares of Series C preferred stock, all of which will be exercised immediately prior to this offering into such number of shares of Series C preferred stock, which will then automatically convert into 86,998,187 shares of our common stock upon the consummation of this offering.

Registration Rights

Following the expiration of the lock-up period described below in “Shares Eligible for Future Sale — Lock-Up Agreements,” the holders of                  shares of common stock, which includes, 2,604,460 shares of common stock, 96,333,792 shares of common stock issuable upon conversion of all of our outstanding preferred stock (including the conversion of the shares of Series C preferred stock to be issued upon the exercise of our Series C warrants upon the consummation of this offering) and                  shares of our common stock issuable upon conversion of our convertible notes upon completion of the offering made hereby (including the shares of our common stock to be purchased in connection with the offering made hereby by Arcapita Ventures I Limited in exchange for the cancellation of outstanding notes it holds), and 99,354 shares of common stock issuable pursuant to the exercise of warrants or their transferees, are entitled to certain registration rights with respect to these securities as set forth in an agreement between us and the holders of these securities. We are generally required to pay all expenses incurred in connection with registrations effected in connection with the following rights, excluding underwriting discounts and commissions. All registration rights described below shall terminate at the earlier of (1) the seventh anniversary of the completion of this offering, provided this offering constitutes a qualified public offering under our existing fourth amended and restated certificate of incorporation, as amended, (2) such shares have been registered under the Securities Act, such registration statement has been declared effective and the shares have been disposed of pursuant to such effective registration statement, and (3) with respect to any holder of registrable shares that (together with its affiliates) holds less than 1% of our common stock (on an as-if-converted to common stock basis), when such holder can sell all of such shares without limitation under Rule 144 promulgated under the Securities Act during any 90 day period.

Demand rights. At any time after six months after the completion of this offering, subject to specified limitations, the holders representing at least a majority of these registrable shares then outstanding may require that we register all or a portion of these securities for sale under the Securities Act, which we refer to as a demand registration, if the anticipated aggregate offering price of such securities is at least $10,000,000. We may be required to effect up to two such registrations at our expense and up to two such registrations at the holders’ expense. Stockholders with these registration rights who are not part of an initial registration demand are entitled to notice and are entitled to include their shares of common stock in the registration. Under certain circumstances, the underwriters, if any, may limit the number of shares included in any such registration.

Piggyback rights. If we propose to register any of our equity securities under the Securities Act, other than in connection with (i) a registration relating solely to our employee benefit plans, or (ii) a registration relating solely to a business combination or merger involving us, the holders of these registrable shares are entitled to notice of such registration and are entitled to include their shares of common stock in the registration. In addition, we are not required to include any registrable shares in the registration in connection with our initial public offering. Under certain circumstances, the underwriters, if any, may limit the number of shares included in any such registration.

Form S-3 rights. If we become eligible to file registration statements on Form S-3, subject to specified limitations, the holders of these registrable shares may require us to register all or a portion of their registrable

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shares on Form S-3, if the anticipated aggregate offering price of such securities is at least $2,000,000. Such requests for registration shall not be considered a demand registration pursuant to the “— Demand rights” section above. We are not required to (i) effect more than two such registrations in any 12-month period or (ii) keep effective at any one time more than one registration statement on Form S-3. Stockholders with these registration rights who are not part of an initial registration demand are entitled to notice and are entitled to include their shares of common stock in the registration. Under certain circumstances, the underwriters, if any, may limit the number of shares included in any such registration.

Anti-Takeover Effects of Delaware Law and Our Restated Certificate of Incorporation and Restated By-Laws

The provisions of Delaware law, our restated certificate of incorporation to be filed upon completion of this offering and our restated by-laws to be effective upon completion of this offering discussed below could discourage or make it more difficult to accomplish a proxy contest or other change in our management or the acquisition of control by a holder of a substantial amount of our voting stock. It is possible that these provisions could make it more difficult to accomplish, or could deter, transactions that stockholders may otherwise consider to be in their best interests or in our best interests. These provisions are intended to enhance the likelihood of continuity and stability in the composition of our board of directors and in the policies formulated by the board of directors and to discourage certain types of transactions that may involve an actual or threatened change of our control. These provisions are designed to reduce our vulnerability to an unsolicited acquisition proposal and to discourage certain tactics that may be used in proxy fights. Such provisions also may have the effect of preventing changes in our management.

Delaware Statutory Business Combinations Provision

We are subject to the anti-takeover provisions of Section 203 of the Delaware General Corporation Law. Section 203 prohibits a publicly-held Delaware corporation from engaging in a “business combination” with an “interested stockholder” for a period of three years after the date of the transaction in which the person became an interested stockholder, unless the business combination is, or the transaction in which the person became an interested stockholder was, approved in a prescribed manner or another prescribed exception applies. For purposes of Section 203, a “business combination” is defined broadly to include a merger, asset sale or other transaction resulting in a financial benefit to the interested stockholder, and, subject to certain exceptions, an “interested stockholder” is a person who, together with his or her affiliates and associates, owns, or within three years prior, did own, 15% or more of the corporation’s voting stock.

Classified Board of Directors; Removal of Directors for Cause

Our restated certificate of incorporation and restated by-laws to be effective upon completion of this offering provide that upon completion of this offering, our board of directors will be divided into three classes, with the term of office of the first class to expire at the first annual meeting of stockholders following the initial classification of directors, the term of office of the second class to expire at the second annual meeting of stockholders following the initial classification of directors and the term of office of the third class to expire at the third annual meeting of stockholders following the initial classification of directors. At each annual meeting of stockholders, directors elected to succeed those directors whose terms expire will be elected for a three-year term of office. All directors elected to our classified board of directors will serve until the election and qualification of their respective successors or their earlier resignation or removal. The board of directors is authorized to create new directorships and to fill such positions so created and is permitted to specify the class to which any such new position is assigned. The person filling such position would serve for the term applicable to that class. The board of directors, or its remaining members, even if less than a quorum, is also empowered to fill vacancies on the board of directors occurring for any reason for the remainder of the term of the class of directors in which the vacancy occurred. Members of the board of directors may only be removed for cause and only by the affirmative vote of 75% of our outstanding voting stock. These provisions are likely to increase the time

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required for stockholders to change the composition of the board of directors. For example, at least two annual meetings will be necessary for stockholders to effect a change in a majority of the members of the board of directors.

Advance Notice Provisions for Stockholder Proposals and Stockholder Nominations of Directors

Our restated by-laws provide that, for nominations to the board of directors or for other business to be properly brought by a stockholder before a meeting of stockholders, the stockholder must first have given timely notice of the proposal in writing to our Secretary. For an annual meeting, a stockholder’s notice generally must be delivered not less than 90 days nor more than 120 days prior to the anniversary of the previous year’s annual meeting. For a special meeting, the notice must generally be delivered not earlier than the 90th day prior to the meeting and not later than the later of (1) the 60th day prior to the meeting or (2) the 10th day following the day on which public announcement of the meeting is first made. Detailed requirements as to the form of the notice and information required in the notice are specified in the restated by-laws. If it is determined that business was not properly brought before a meeting in accordance with our bylaw provisions, such business will not be conducted at the meeting.

Special Meetings of Stockholders

Special meetings of the stockholders may be called only by our board of directors pursuant to a resolution adopted by a majority of the total number of directors.

No Stockholder Action by Written Consent

Our restated certificate of incorporation and restated by-laws do not permit our stockholders to act by written consent. As a result, any action to be effected by our stockholders must be effected at a duly called annual or special meeting of the stockholders.

Super Majority Stockholder Vote Required for Certain Actions

The Delaware General Corporation Law provides generally that the affirmative vote of a majority of the shares entitled to vote on any matter is required to amend a corporation’s certificate of incorporation or by-laws, unless the corporation’s certificate of incorporation or by-laws, as the case may be, requires a greater percentage. Our restated certificate of incorporation requires the affirmative vote of the holders of at least 75% of our outstanding voting stock to amend or repeal any of the provisions discussed in this section of this prospectus entitled “— Anti-Takeover Effects of Delaware Law and Our Restated Certificate of Incorporation and Restated By-Laws” or to reduce the number of authorized shares of common stock or preferred stock. This 75% stockholder vote would be in addition to any separate class vote that might in the future be required pursuant to the terms of any preferred stock that might then be outstanding. In addition, a 75% vote is also required for any amendment to, or repeal of, our restated by-laws by the stockholders. Our restated by-laws may be amended or repealed by a simple majority vote of the board of directors.

Exclusive Forum

Our restated certificate of incorporation provides that, subject to limited exceptions, a state or federal court located within the State of Delaware will be the sole and exclusive forum for (1) any derivative action or proceeding brought on our behalf, (2) any action asserting a claim of breach of a fiduciary duty owed by any of our directors, officers or other employees to us or our stockholders, (3) any action asserting a claim against us arising pursuant to any provision of the Delaware General Corporation Law, our certificate of incorporation or our by-laws, or (4) any other action asserting a claim against us that is governed by the internal affairs doctrine. Any person or entity purchasing or otherwise acquiring any interest in shares of our capital stock shall be deemed

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to have notice of and to have consented to the provisions of our restated certificate of incorporation described above. Although we believe these provisions benefit us by providing increased consistency in the application of Delaware law for the specified types of actions and proceedings, the provisions may have the effect of discouraging lawsuits against our directors and officers. The enforceability of similar choice of forum provisions in other companies’ certificates of incorporation has been challenged in legal proceedings, and it is possible that, in connection with one or more actions or proceedings described above, a court could find the choice of forum provisions contained in our restated certificate of incorporation to be inapplicable or unenforceable.

Transfer Agent and Registrar

The transfer agent and registrar for our common stock is                 .

Stock Market Listing

We intend to apply to list our common stock on the NYSE under the symbol “ASPN.”

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DESCRIPTION OF CERTAIN INDEBTEDNESS

Set out below is a description of certain of our outstanding indebtedness and our revolving credit facility.

Subordinated Notes

In December 2010, we entered into a subordinated note and warrant purchase agreement with affiliates of Piper Capital LLC and other investors and issued an aggregate of $10.0 million principal amount of subordinated notes. In June 2011, June 2011, December 2011, June 2012, September 2012 and March 2013, we amended the subordinated note and warrant purchase agreement to revise the maturity date and other terms in connection with the various issuances of our convertible notes. The subordinated notes bear interest at the rate of 20% per annum and are required to be repaid upon the earlier of: (i) September 30, 2014, (ii) the first anniversary of the completion of this offering or (iii) the last business day prior to the date that any of our preferred stock is redeemed. The subordinated note and warrant purchase agreement contains standard restrictive covenants that impose significant operating and financial restrictions on our operations. As of December 31, 2013, the total outstanding principal and accrued interest under the subordinated notes was $17.3 million. In connection with the issuance of the subordinated notes, we issued warrants to purchase 149,611 shares of our common stock, of which warrants to purchase 99,342 shares of our common stock remain outstanding and which are further described in “Description of Capital Stock – Warrants.”

The subordinated notes are secured by a first priority lien on all real property and equipment located at our East Providence facility and a second priority lien on all other assets, including all our intellectual property and all accounts, equipment, inventory and receivables. We intend to repay all outstanding principal and accrued and unpaid interest of the subordinated notes with a portion of the proceeds from this offering.

Revolving Credit Facility

In March 2011, we entered into a $10.0 million revolving credit facility with Silicon Valley Bank. Due to a borrowing limitation under the terms of the credit facility, the effective amount available to us under the credit facility is $8.6 million, of which $6.4 million remained available to us as of December 31, 2013 after giving effect to the $1.0 million drawn on the line of credit and the $1.2 million of outstanding letters of credit. As of April 15, 2014, we had $1.5 million drawn on the line of credit and $1.2 million of outstanding letters of credit. In June 2011, June 2011, December 2011, June 2012, September 2012, September 2012, March 2013, June 2013 and November 2013, we amended the agreement in connection with the various issuances of our convertible notes. Interest on amounts outstanding under the revolving credit facility is equal to the greater of the prime rate or 4% per annum, plus 1.0% per annum. In addition, we are required to pay a quarterly unused revolving line facility fee of 0.5% per annum of the average unused portion of the revolving credit facility. The revolving credit facility contains standard restrictive covenants that impose significant operating and financial restrictions on our operations and also contains events of default customary for credit facilities of this type, including, among other things, nonpayment of principal or interest when due. The revolving credit facility will mature on July 27, 2014.

The revolving credit facility is secured by a second priority lien on all real property and equipment located at our East Providence facility and a first priority lien on all other assets, including all our intellectual property and all accounts, equipment, inventory and receivables.

Convertible Promissory Notes

Pursuant to our note purchase agreement dated June 1, 2011, as amended, we issued $30.0 million in aggregate principal amount of convertible notes to certain accredited investors on June 1, 2011 and June 14, 2011. We refer to these convertible notes as the June 2011 convertible notes. These convertible notes accrue interest at the rate of 8% per year and have a maturity date of June 1, 2016.

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Pursuant to our note purchase agreement dated December 6, 2011, as amended, we issued $15.8 million in aggregate principal amount of convertible notes to certain accredited investors on December 6, 2011 and March 1, 2012. We refer to these convertible notes as the December 2011 convertible notes. These convertible notes accrue interest at the rate of 8% per year and have a maturity date of December 6, 2016, except that $0.3 million in principal amount of these convertible notes have a maturity date of December 6, 2014. In addition, due to the investment restrictions of one of our principal stockholders, the December 2011 convertible note having an aggregate principal amount of $0.6 million held by such stockholder is noninterest bearing and does not automatically convert into shares of our common stock, but the holder will purchase immediately prior to this offering a number shares based on the initial public offering price and a discount factor that will result in the holder receiving approximately the number of shares that such holder would have received if this note had automatically converted upon the same terms as the December 2011 convertible notes in exchange for the cancellation of its notes.

Pursuant to our note purchase agreement dated June 11, 2012, as amended, we issued $27.6 million in aggregate principal amount of convertible notes to certain accredited investors on June 11, 2012, July 17, 2012, September 26, 2012, October 5, 2012, November 28, 2012 and January 9, 2013. We refer to these convertible notes as the June 2012 convertible notes. These convertible notes accrue interest at a rate of 8% per year and have a maturity date of December 6, 2016, except that less than $0.1 million of these convertible notes have a maturity date of December 6, 2014. Certain of these convertible notes having an aggregate principal amount of $7.5 million were subsequently exchanged for convertible notes issued on March 28, 2013 and May 6, 2013, as further described in the paragraph below. In addition, due to the investment restrictions of one of our principal stockholders, the June 2012 convertible notes having an aggregate principal amount of $2.9 million held by such stockholder are noninterest bearing and do not automatically convert into shares of our common stock, but the holder will purchase immediately prior to this offering a number shares based on the initial public offering price and a discount factor that will result in the holder receiving approximately the number of shares that such holder would have received if these notes had automatically converted upon the same terms as the June 2012 convertible notes in exchange for the cancellation of its notes.

Pursuant to our note and warrant purchase agreement dated March 28, 2013, we issued $22.5 million in aggregate principal amount of convertible notes to certain accredited investors on March 28, 2013 and May 6, 2013. We refer to these convertible notes as the March 2013 convertible notes, and we refer to the June 2011 convertible notes, December 2011 convertible notes, June 2012 convertible notes and March 2013 convertible notes collectively as the convertible notes. The March 2013 convertible notes accrue interest at a rate of 8% per year and have a maturity date of March 28, 2016. Of the $22.5 million of aggregate principal amount of March 2013 convertible notes that we issued, $7.5 million in principal amount of the March 2013 convertible notes were issued in exchange for $7.5 million in principal amount of the June 2012 convertible notes that were issued on November 28, 2012 and January 9, 2013. In addition, due to the investment restrictions of one of our principal stockholders, March 2013 convertible notes having an aggregate principal amount of $3.0 million held by such stockholder are noninterest bearing and are not convertible into shares of our common stock, but the holder has an option to convert these non-convertible notes into the same number of shares of our common stock that such notes would automatically convert in this offering as if they were convertible on the same terms as the other March 2013 convertible notes. In connection with the issuance of the March 2013 convertible notes, we issued warrants to purchase 87,018,187 shares of our Series C preferred stock having an exercise price of $.0001 per share, which we assume will be exercised in connection with this offering.

The unpaid principal amount plus accrued interest of the convertible notes will automatically convert upon the closing of the offering made hereby into a number of shares of our common stock equal to the quotient obtained by dividing the unpaid principal amount of the convertible notes plus interest accrued but unpaid thereon, by 62.5% of the initial public offering price. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $             per share, which is the mid-point of the price range set forth on the

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cover page of the prospectus included in this registration statement, the $             million in outstanding principal amount and accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock. The convertible notes are not secured. The holders of these convertible notes will be entitled to registration rights provided in our registration rights agreement with regard to the shares of common stock issued upon conversion of these convertible notes.

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SHARES ELIGIBLE FOR FUTURE SALE

Prior to this offering, there has been no public market for our common stock, and a liquid public trading market for our common stock may not develop or be sustained after this offering. If a public market does develop, future sales of significant amounts of our common stock, including shares issued upon exercise of outstanding options or warrants, or the anticipation of those sales, could adversely affect the public market prices prevailing from time to time and could impair our ability to raise capital through sales of our equity securities. We intend to apply to list our common stock on the NYSE under the symbol “ASPN.”

Upon the closing of the offering made hereby, we will have outstanding an aggregate of                  shares of common stock, assuming no exercise by the underwriters of their option to purchase additional shares and no exercise of outstanding options. Of these shares, all of the shares of our common stock sold in this offering will be freely tradable without restriction or further registration under the Securities Act, except for any shares of our common stock purchased by our “affiliates,” as that term is defined in Rule 144 under the Securities Act, whose sales would be subject to the Rule 144 resale restrictions described below.

The remaining shares of common stock will be “restricted securities,” as that term is defined in Rule 144 under the Securities Act. These restricted securities are eligible for public sale only if they are registered under the Securities Act or if they qualify for an exemption from registration under the Securities Act. One such safe-harbor exemption is Rule 144, which is summarized below.

Subject to the lock-up agreements described below and the provisions of Rule 144 under the Securities Act, these restricted securities and shares sold in this offering will be available for sale in the public market as follows:

Date Available for Sale	Shares Eligible for Sale	Comment
Date of prospectus		Shares sold in the offering and shares that can be sold under Rule 144 that are not subject to a lock-up
180 days* after date of prospectus		Lock-up released; shares can be sold under Rule 144

* 180 days corresponds to the lock-up period described below in “— Lock-up Agreements.” However, Barclays Capital Inc. may in its sole discretion, at any time without prior notice, release all or any portion of the shares from the restrictions in any of these agreements.

In addition, of the 80,050,105 shares of our common stock that were issuable upon the exercise of stock options outstanding as of April 15, 2014, options to purchase 9,553,017 shares were exercisable as of April 15, 2014 and, upon exercise, these shares will be eligible for sale in the public markets, subject to the lock-up agreements and securities laws described below.

Rule 144

Affiliate Resales of Shares

Affiliates of ours must generally comply with Rule 144 if they wish to sell in the public market any shares of our common stock, whether or not those shares are “restricted securities.” “Restricted securities” are any securities acquired from us or one of our affiliates in a transaction not involving a public offering. All shares of our common stock issued prior to the closing of the offering made hereby, and the shares of common stock issuable upon the conversion of our preferred stock and our convertible notes, are considered to be restricted securities. The shares of our common stock sold in this offering are not considered to be restricted securities.

In general, subject to the lock-up agreements described below, beginning 90 days after the effective date of the registration statement of which this prospectus is a part, a person who is an affiliate of ours, or who was an affiliate of ours at any time during the three months immediately before a sale can sell restricted shares of our common stock in compliance with the following requirements of Rule 144.

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Holding Period. If the shares are restricted securities, an affiliate must have beneficially owned the shares of our common stock for at least six months.

Manner of Sale. An affiliate must sell its shares in “broker’s transactions” or certain “riskless principal transactions” or to market makers, each within the meaning of Rule 144.

Limitation on Number of Shares Sold. An affiliate is only allowed to sell within any three-month period an aggregate number of shares of our common stock that does not exceed the greater of:

• one percent of the number of the total number of shares of our common stock then outstanding, which will equal approximately              shares immediately after this offering; and

• the average weekly trading volume in our common stock on the stock exchange where our common stock is traded during the four calendar weeks preceding either (i) to the extent that the seller is required to file a notice on Form 144 with respect to such sale, the date of filing such notice, (ii) date of receipt of the order to execute the transaction by the broker or (iii) the date of execution of the transaction with the market maker.

Current Public Information. An affiliate may only resell its restricted securities to the extent that adequate current public information, as defined in Rule 144, is available about us, which, in our case, means that we have been subject to the reporting requirements of Section 13 or 15(d) of the Exchange Act for a period of at least 90 days prior to the date of the sale and we have filed all reports with the SEC required by those sections during the preceding twelve months (or such shorter period that we have been subject to these filing requirements).

Notice on Form 144. If the number of shares of our common stock being sold by an affiliate under Rule 144 during any three-month period exceeds 5,000 shares or has an aggregate sale price in excess of $50,000, then the seller must file a notice on Form 144 with the SEC and the stock exchange on which our common stock is traded concurrently with either the placing of a sale order with the broker or the execution directly with a market maker.

Non-Affiliate Resales of Restricted Shares

Any person or entity who is not an affiliate of ours and who has not been an affiliate of ours at any time during the three months preceding a sale is only required to comply with Rule 144 in connection with sales of restricted shares of our common stock. Subject to the lock-up agreements described below, those persons may sell shares of our common stock that they have beneficially owned for at least one year without any restrictions under Rule 144 immediately following the effective date of the registration statement of which this prospectus is a part.

Further, beginning 90 days after the effective date of the registration statement of which this prospectus is a part, a person who is not an affiliate of ours at the time such person sells shares of our common stock, and has not been an affiliate of ours at any time during the three months preceding such sale, and who has beneficially owned such shares of our common stock, as applicable, for at least six months but less than a year, is entitled to sell such shares so long as there is adequate current public information, as defined in Rule 144, available about us.

Resales of restricted shares of our common stock by non-affiliates are not subject to the manner of sale, volume limitation or notice filing provisions of Rule 144, described above.

Rule 701

Rule 701 under the Securities Act applies to shares purchased from us by our employees, directors or consultants, in connection with a qualified compensatory stock plan or other written agreement, either prior to the

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date of this prospectus or pursuant to the exercise of options granted prior to the date of this prospectus. Shares issued in reliance on Rule 701 are “restricted securities,” but may be sold in the public market beginning 90 days after the date of this prospectus (i) by our affiliates, subject to compliance with the provisions of Rule 144 other than its one-year holding period requirement, and (ii) by persons other than our affiliates, subject only to the manner of sale provisions of Rule 144.

Lock-up Agreements

Holders of                  outstanding shares of our common stock, including our principal stockholders and each of our officers and directors, have agreed with the underwriters, subject to certain exceptions, not to offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise dispose of any shares of our common stock, or any options or warrants to purchase any shares of our common stock, or any securities convertible into, exchangeable for or that represent the right to receive shares of our common stock for a period through the date 180 days after the date of this prospectus, except with the prior written consent of Barclays Capital Inc. on behalf of the underwriters.

Barclays Capital Inc. currently does not anticipate shortening or waiving any of the lock-up agreements and do not have any pre-established conditions for such modifications or waivers. Barclays Capital Inc. may, however, release for sale in the public market all or any portion of the shares subject to the lock-up agreement.

Stock Options

As of April 15, 2014, there were outstanding options to purchase 80,050,105 shares of our common stock at a weighted-average exercise price of $0.112 per share, of which options to purchase 9,553,017 shares were exercisable as of April 15, 2014. Following this offering, we intend to file a registration statement on Form S-8 under the Securities Act to register all of the shares subject to outstanding options and options and other awards issuable under the 2001 equity incentive plan and the 2014 equity incentive plan. See “Executive and Director Compensation — Equity Incentive Plans” for additional information regarding these plans.

Warrants

As of April 15, 2014, there were outstanding warrants to purchase an aggregate of 112,576 shares of our common stock at a weighted-average exercise price of $0.017 per share and outstanding warrants to purchase 86,998,187 shares of Series C preferred stock at an exercise price of $0.0001 per share. We assume that all of the outstanding Series C warrants will be exercised upon the consummation of this offering. Any shares purchased pursuant to these warrants will be “restricted shares” and may be sold in the public market only if they are registered under the Securities Act or qualify for an exemption from such registration.

Registration Rights

Upon expiration of the lock-up period described above in “— Lock-Up Agreements,” the holders of                  shares of common stock and 99,354 shares of common stock issuable pursuant to the exercise of warrants, or their transferees, will be entitled to various rights with respect to the registration of these shares under the Securities Act. See “Description of Capital Stock — Registration Rights.” Registration of these shares under the Securities Act would result in these shares becoming freely tradable without restriction under the Securities Act immediately upon the effectiveness of the registration, except for shares then held by affiliates.

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MATERIAL U.S. FEDERAL TAX CONSIDERATIONS FOR NON-U.S. HOLDERS

The following is a general discussion of the material U.S. federal income tax consequences of the ownership and disposition of our common stock by a non-U.S. holder (as defined below) who holds our common stock as a capital asset (generally, property held for investment). For purposes of this discussion, you are a “non-U.S. holder” if you are a beneficial owner of our common stock that is an individual, corporation (or other entity treated as a corporation for federal income tax purposes), estate or trust (other than a grantor trust) and you are not, for U.S. federal income tax purposes:

• an individual who is a citizen or resident of the U.S.;

• a corporation (or other entity treated as a corporation for U.S. federal income tax purposes) created or organized in or under the laws of the U.S., or of any state thereof or the District of Columbia; or

• an estate whose income is subject to U.S. federal income taxation regardless of its source; or a trust, in general, if a U.S. court is able to exercise primary supervision over the administration of the trust and one or more United States persons have authority to control all substantial decisions of the trust or if the trust has made a valid election to be treated as a United States person under applicable U.S. Treasury regulations.

If you are an individual, you may be treated as a resident of the U.S. in any calendar year for U.S. federal income tax purposes by, among other ways, being present in the U.S. for at least 31 days in that calendar year and for an aggregate of at least 183 days during a three-year period ending in the current calendar year (and where certain other conditions are satisfied and certain applicable exceptions do not apply, including exceptions applicable under certain tax treaties). For purposes of this calculation, you would count all of the days present in the current year, one-third of the days present in the immediately preceding year and one-sixth of the days present in the second preceding year.

This discussion does not consider:

• U.S. state, U.S. local, U.S. estate or non-U.S. tax consequences;

• all aspects of U.S. federal income taxes or specific facts and circumstances that may be relevant to a particular non-U.S. holder’s tax position;

• the tax consequences for the stockholders or beneficiaries of a non-U.S. holder;

• special tax rules that may apply to particular holders, such as financial institutions, insurance companies, tax-exempt organizations, controlled foreign corporations, passive foreign investment companies, regulated investment companies, government instrumentalities, holders owning more than 5% of our common stock, pension plans, U.S. expatriates, former citizens or residents of the U.S., partnerships or other flow-through entities, part-year non-resident aliens, broker-dealers and traders in securities, persons who elect to mark-to-market their securities; or

• special tax rules that may apply to a non-U.S. holder that holds our common stock as part of a “straddle,” “hedge,” “conversion transaction,” “synthetic security” or other integrated investment.

If a partnership, including any entity or arrangement treated as a partnership for U.S. federal income tax purposes, is a holder of our common stock, the tax treatment of a partner in the partnership will generally depend upon the status of the partner and the activities of the partnership. If you are a partnership that may acquire our common stock, or a partner in such a partnership, you should consult a tax advisor regarding the tax consequences to you of the partnership’s acquisition, ownership and disposition of our common stock.

The following discussion is based on provisions of the U.S. Internal Revenue Code of 1986, as amended (the “Code”), existing and proposed Treasury regulations and administrative and judicial interpretations, all as of the date of this prospectus supplement, and all of which are subject to change, retroactively or prospectively. The following summary assumes that you hold our common stock as a capital asset (generally, property held for

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investment). We undertake no obligation to publicly update or otherwise revise this summary whether as a result of new Treasury regulations, Code sections, judicial and administrative interpretations or otherwise. The Code, Treasury Regulations and judicial and administrative interpretations thereof are also subject to various interpretations, and there can be no guarantee that the Internal Revenue Service, or the IRS, or U.S. courts will agree with the tax consequences described in this summary.

Each non-U.S. holder should consult a tax advisor regarding the U.S. federal, state, local and non-U.S. income, tax treaty and other tax consequences of holding and disposing of shares of our common stock.

Dividends

We do not anticipate making cash distributions on our common stock in the foreseeable future. In the event, however, that we make distributions on our common stock, those payments will constitute dividends for U.S. federal tax purposes to the extent paid from our current or accumulated earnings and profits, as determined under U.S. federal income tax principles. To the extent those distributions exceed our current and accumulated earnings and profits, they first will constitute a return of capital and will reduce a non-U.S. holder’s basis in our common stock, but not below zero, and then will be treated as gain from the sale of stock. Any dividend paid to a non-U.S. holder on our common stock that is not effectively connected with the non-U.S. holder’s conduct of a U.S. trade or business will generally be subject to U.S. federal withholding tax at a rate of 30%, or a lower rate under an applicable income tax treaty.

You should consult your tax advisor regarding your entitlement to benefits under a relevant income tax treaty. Generally, in order for us to withhold tax at a lower treaty rate, you must (a) timely provide the payor with a properly executed applicable IRS Form W-8 (or other applicable successor form) and any applicable attachments certifying that (i) you are not a United States person and (ii) you are eligible for the lower treaty rate or (b) if our common stock is held through certain foreign intermediaries, timely satisfy the relevant certification requirements of applicable U.S. Treasury regulations. The applicable certifications must be provided to the applicable withholding agent prior to the payment of dividends and may be required to be updated periodically.

If you are eligible for a reduced rate of U.S. federal withholding tax under an income tax treaty, you may obtain a refund or credit of any excess amounts withheld by filing an appropriate claim for a refund on a timely basis with the IRS.

If the dividend is effectively connected with your conduct of a trade or business in the U.S. and, if required by an applicable income tax treaty, is attributable to a permanent establishment maintained by you in the U.S., the dividend will generally be exempt from U.S. federal withholding tax, provided that you supply us with a properly executed IRS Form W-8ECI. In this case, the dividend will be taxed on a net income basis at the regular graduated rates and in the manner applicable to U.S. persons and, if you are a foreign corporation, you may be subject to an additional branch profits tax at a rate of 30% or a lower rate as may be specified by an applicable income tax treaty.

Sales, Exchanges or Other Taxable Dispositions of Common Stock

Subject to the discussions below regarding backup withholding and “FATCA” (as defined below), you generally will not be subject to U.S. federal income tax on gain recognized on a disposition of our common stock unless:

• the gain is effectively connected with your conduct of a trade or business in the U.S. and, if required by an applicable income tax treaty, is attributable to a permanent establishment maintained by you in the U.S., in which case the gain will be taxed on a net income basis at the regular graduated rates and in the manner applicable to United States persons and, if you are a foreign corporation, you may be subject to an additional branch profits tax at a rate of 30% or a lower rate as may be specified by an applicable income tax treaty;

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• you are an individual who holds our common stock as a capital asset, are present in the U.S. for 183 days or more in the taxable year of the disposition and meet other requirements, in which case the gain derived from the sale will be subject to a flat 30% tax, which may be offset by U.S. source capital losses; or

• we are or have been a “United States real property holding corporation,” or USRPHC, for U.S. federal income tax purposes at any time during the shorter of the five-year period ending on the date of disposition and the period that you held our common stock and certain other conditions are met, in which case the gain will be taxed on a net income basis in the manner described in the first bullet paragraph above.

Generally, a corporation is a USRPHC if the fair market value of its “United States real property interests” equals or exceeds 50% of the sum of the fair market value of its worldwide real property interests plus its other assets used or held for use in a trade or business. The tax relating to stock in a USRPHC generally will not apply to a non-U.S. holder whose holdings, direct and indirect, at all times during the applicable period, constituted 5% or less of our common stock, provided that our common stock was regularly traded (within the meaning of section 897(c)(3) of the Code) on an established securities market in the calendar year of disposition. We believe that we are not currently, and we do not anticipate becoming in the future, a USRPHC for U.S. federal income tax purposes.

Information Reporting and Backup Withholding

We must report annually to the IRS and to each non-U.S. holder the amount of dividends paid to such holder and the tax withheld with respect to such dividends, regardless of whether withholding was required. Copies of the information returns reporting such dividends and withholding may also be made available to the tax authorities in other countries under the provisions of an applicable income tax treaty.

Payments of dividends in respect of our common stock, or proceeds on the disposition of our common stock effected within the United States or through certain United States-related financial intermediaries, paid to a Non-U.S. Holder may be subject to additional information reporting and backup withholding unless such Non-U.S. Holder establishes an exemption, for example, by properly certifying that such Non-U.S. Holder is not a United States person as defined under the Code on a valid IRS Form W-8BEN or another appropriate version of IRS Form W-8 and including any applicable attachments (provided that the payor does not have actual knowledge or reason to know that such Non-U.S. Holder is a United States person).

Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from payments made to a Non-U.S. Holder will reduce the Non-U.S. Holder’s U.S. federal income tax liability. If withholding results in an overpayment of taxes, a refund or credit may generally be obtained from the IRS, provided the required information is timely furnished to the IRS. A Non-U.S. Holder should consult its tax advisor regarding the application of the information reporting and backup withholding rules.

Additional Withholding Requirements

Under legislation enacted in 2010, U.S. Treasury regulations and official IRS administrative guidance (commonly known as “FATCA”), a 30% U.S. federal withholding tax may apply to any dividends paid after June 30, 2014, and to the gross proceeds from a disposition of our common stock occurring after December 31, 2016, in each case paid to (i) a “foreign financial institution” (as specifically defined in the legislation), whether such foreign financial institution is the beneficial owner or an intermediary, unless such foreign financial institution agrees to verify, report and disclose its United States “account” holders (as specifically defined in the legislation) and meets certain other specified requirements or (ii) a non-financial foreign entity, whether such non-financial foreign entity is the beneficial owner or an intermediary, unless such entity provides a certification that the beneficial owner of the payment does not have any substantial United States owners or provides the name, address and taxpayer identification number of each such “substantial United States owner” ( as defined under the Code and applicable Treasury regulations) and certain other specified requirements are met. In certain

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cases, the relevant foreign financial institution or non-financial foreign entity may qualify for an exemption from, or be deemed to be in compliance with, these rules. Persons located in a jurisdiction that has entered into an intergovernmental agreement with the U.S. governing FATCA (an IGA) may be subject to different rules. Application of this FATCA tax does not depend on whether the payment otherwise would be exempt from U.S. federal withholding tax under the other exemptions described above. Prospective holders should consult their own tax advisors regarding this new legislation, any applicable IGA and whether this legislation or IGA may be relevant to your ownership and disposition of our common stock.

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UNDERWRITING

Barclays Capital Inc. is acting as representative of the underwriters and joint book-running manager of this offering. J.P. Morgan Securities LLC and Citigroup Global Markets Inc. are also acting as joint book-running managers. Under the terms of an underwriting agreement, which will be filed as an exhibit to the registration statement of which this prospectus is a part, each of the underwriters named below has severally agreed to purchase from us the respective number of shares of common stock shown opposite its name below:

Underwriters	Number of Shares
Barclays Capital Inc.
J.P. Morgan Securities LLC
Citigroup Global Markets Inc.
Total

The underwriting agreement provides that the underwriters’ obligation to purchase shares of common stock depends on the satisfaction of the conditions contained in the underwriting agreement including:

• the obligation to purchase all of the shares of common stock offered hereby (other than those shares of common stock covered by their option to purchase additional shares as described below), if any of the shares are purchased;

• the representations and warranties made by us to the underwriters are true;

• there is no material change in our business or the financial markets; and

• we deliver customary closing documents to the underwriters.

Commissions and Expenses

The following table summarizes the underwriting discounts and commissions we will pay to the underwriters. These amounts are shown assuming both no exercise and full exercise of the underwriters’ option to purchase additional shares. The underwriting fee is the difference between the initial price to the public and the amount the underwriters pay to us for the shares.

	No Exercise	Full Exercise
Per share	$	$
Total	$	$

The representative of the underwriters has advised us that the underwriters propose to offer the shares of common stock directly to the public at the public offering price on the cover of this prospectus and to selected dealers, which may include the underwriters, at such offering price less a selling concession not in excess of $                 per share. After the offering, the representative may change the offering price and other selling terms. Sales of shares made outside of the United States may be made by affiliates of the underwriters.

The expenses of the offering that are payable by us are estimated to be $                  million (excluding the underwriting discounts and commissions). We have agreed to reimburse the underwriters for expenses related to the clearing of this offering with the Financial Industry Regulatory Authority, Inc. (“FINRA”) in an amount up to $                . Such reimbursement is deemed to be underwriting compensation by FINRA.

Option to Purchase Additional Shares

We have granted the underwriters an option exercisable for 30 days after the date of the underwriting agreement, to purchase, from time to time, in whole or in part, up to an aggregate of                  shares at the public offering price less the underwriting discounts and commissions. This option may be exercised if the underwriters sell more than shares in connection with this offering. To the extent that this option is exercised,

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each underwriter will be obligated, subject to certain conditions, to purchase its pro rata portion of these additional shares based on the underwriter’s underwriting commitment in the offering as indicated in the table at the beginning of this Underwriting section.

Lock-Up Agreements

We, all of our directors and executive officers, and holders of substantially all our outstanding stock and vested options have agreed that, without the prior written consent of Barclays Capital Inc., we and they will not, prior to the date that is 180 days after the date of this prospectus, (a) offer, sell, contract to sell, pledge, grant any option to purchase, make any short sale or otherwise transfer or dispose of, directly or indirectly, or file with the SEC a registration statement under the Securities Act relating to, any securities of the Company that are substantially similar to the common stock, including but not limited to any options or warrants to purchase shares of common stock or any securities that are convertible into or exchangeable for, or that represent the right to receive, common stock or any such substantially similar securities, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing or (b) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the common stock or any such other securities, whether any such transaction described in clause (a) or (b) above is to be settled by delivery of common stock or such other securities, in cash or otherwise. The foregoing restrictions are subject to certain customary exceptions.

Barclays Capital Inc., in its sole discretion, may release the common stock and other securities subject to the lock-up agreements described above in whole or in part at any time with or without notice. When determining whether or not to release common stock and other securities from lock-up agreements, Barclays Capital Inc. will consider, among other factors, the holder’s reasons for requesting the release, the number of shares of common stock and other securities for which the release is being requested and market conditions at the time.

Offering Price Determination

Prior to this offering, there has been no public market for our common stock. The initial public offering price was negotiated between the representative and us. In determining the initial public offering price of our common stock, the representative considered:

• the history and prospects for the industry in which we compete;

• our financial information;

• the ability of our management and our business potential and earning prospects;

• the prevailing securities markets at the time of this offering; and

• the recent market prices of, and the demand for, publicly traded shares of generally comparable companies.

Indemnification

We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act, and to contribute to payments that the underwriters may be required to make for these liabilities.

Stabilization, Short Positions and Penalty Bids

The representative may engage in stabilizing transactions, short sales and purchases to cover positions created by short sales, and penalty bids or purchases for the purpose of pegging, fixing or maintaining the price of the common stock, in accordance with Regulation M under the Exchange Act:

• Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum.

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• A short position involves a sale by the underwriters of shares in excess of the number of shares the underwriters are obligated to purchase in the offering, which creates the syndicate short position. This short position may be either a covered short position or a naked short position. In a covered short position, the number of shares involved in the sales made by the underwriters in excess of the number of shares they are obligated to purchase is not greater than the number of shares that they may purchase by exercising their option to purchase additional shares. In a naked short position, the number of shares involved is greater than the number of shares in their option to purchase additional shares. The underwriters may close out any short position by either exercising their option to purchase additional shares and/or purchasing shares in the open market. In determining the source of shares to close out the short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through their option to purchase additional shares. A naked short position is more likely to be created if the underwriters are concerned that there could be downward pressure on the price of the shares in the open market after pricing that could adversely affect investors who purchase in the offering.

• Syndicate covering transactions involve purchases of the common stock in the open market after the distribution has been completed in order to cover syndicate short positions.

• Penalty bids permit the representative to reclaim a selling concession from a syndicate member when the common stock originally sold by the syndicate member is purchased in a stabilizing or syndicate covering transaction to cover syndicate short positions.

These stabilizing transactions, syndicate covering transactions and penalty bids may have the effect of raising or maintaining the market price of our common stock or preventing or retarding a decline in the market price of the common stock. As a result, the price of the common stock may be higher than the price that might otherwise exist in the open market. These transactions may be effected on the NYSE or otherwise and, if commenced, may be discontinued at any time.

Neither we nor any of the underwriters makes any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of the common stock. In addition, neither we nor any of the underwriters makes any representation that the representative will engage in these stabilizing transactions or that any transaction, once commenced, will not be discontinued without notice.

Electronic Distribution

A prospectus in electronic format may be made available on the Internet sites or through other online services maintained by one or more of the underwriters and/or selling group members participating in this offering, or by their affiliates. In those cases, prospective investors may view offering terms online and, depending upon the particular underwriter or selling group member, prospective investors may be allowed to place orders online. The underwriters may agree with us to allocate a specific number of shares for sale to online brokerage account holders. Any such allocation for online distributions will be made by the representative on the same basis as other allocations.

Other than the prospectus in electronic format, the information on any underwriter’s or selling group member’s web site and any information contained in any other web site maintained by an underwriter or selling group member is not part of the prospectus or the registration statement of which this prospectus forms a part, has not been approved and/or endorsed by us or any underwriter or selling group member in its capacity as underwriter or selling group member and should not be relied upon by investors.

New York Stock Exchange

We intend to apply to list our shares on the NYSE under the symbol “ASPN.” In connection with that listing, the underwriters will undertake to sell the minimum number of common shares to the minimum number of beneficial owners necessary to meet the NYSE listing requirements.

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Discretionary Sales

The underwriters have informed us that they do not intend to confirm sales to discretionary accounts that exceed 5% of the total number of shares offered by them.

Stamp Taxes

If you purchase shares of common stock offered in this prospectus, you may be required to pay stamp taxes and other charges under the laws and practices of the country of purchase, in addition to the offering price listed on the cover page of this prospectus.

Relationships

Certain of the underwriters and their affiliates have engaged, and may in the future engage, in commercial and investment banking transactions with us in the ordinary course of their business. They have received, and expect to receive, customary compensation and expense reimbursement for these commercial and investment banking transactions.

Selling Restrictions

European Economic Area

In relation to each Member State of the European Economic Area which has implemented the Prospectus Directive, each, a Relevant Member State, an offer to the public of any common stock which are the subject of the offering contemplated herein may not be made in that Relevant Member State, except that an offer to the public in that Relevant Member State of any common stock may be made at any time under the following exemptions under the Prospectus Directive, if they have been implemented in that Relevant Member State:

• to legal entities which are qualified investors as defined under the Prospectus Directive;

• by the underwriters to fewer than 100, or, if the Relevant Member State has implemented the relevant provisions of the 2010 PD Amending Directive, 150, natural or legal persons (other than qualified investors as defined in the Prospectus Directive), as permitted under the Prospectus Directive, subject to obtaining the prior consent of the representatives of the underwriters for any such offer; or

• in any other circumstances falling within Article 3(2) of the Prospectus Directive,

provided that no such offer of common stock shall result in a requirement for us or any underwriter to publish a prospectus pursuant to Article 3 of the Prospectus Directive or supplement a prospectus pursuant to Article 16 of the Prospectus Directive.

Each person in a Relevant Member State who receives any communication in respect of, or who acquires any common stock under, the offers contemplated here in this prospectus will be deemed to have represented, warranted and agreed to and with each underwriter and us that:

• it is a qualified investor as defined under the Prospectus Directive; and

• in the case of any common stock acquired by it as a financial intermediary, as that term is used in Article 3(2) of the Prospectus Directive, (i) the common stock acquired by it in the offering have not been acquired on behalf of, nor have they been acquired with a view to their offer or resale to, persons in any Relevant Member State other than qualified investors, as that term is defined in the Prospectus Directive, or in the circumstances in which the prior consent of the representatives of the underwriters has been given to the offer or resale or (ii) where common stock have been acquired by it on behalf of persons in any Relevant Member State other than qualified investors, the offer of such common stock to it is not treated under the Prospectus Directive as having been made to such persons.

For the purposes of this representation and the provision above, the expression an “offer of common stock to the public” in relation to any common stock in any Relevant Member State means the communication in any form and by

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any means of sufficient information on the terms of the offer and any common stock to be offered so as to enable an investor to decide to purchase or subscribe for the common stock, as the same may be varied in that Relevant Member State by any measure implementing the Prospectus Directive in that Relevant Member State, the expression “Prospectus Directive” means Directive 2003/71/EC (and amendments thereto, including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member State), and includes any relevant implementing measure in each Relevant Member State and the expression “2010 PD Amending Directive” means Directive 2010/73/EU.

United Kingdom

This prospectus has only been communicated or caused to have been communicated and will only be communicated or caused to be communicated as an invitation or inducement to engage in investment activity (within the meaning of Section 21 of the Financial Services and Markets Act of 2000, or the FSMA) as received in connection with the issue or sale of the common stock in circumstances in which Section 21(1) of the FSMA does not apply to us. All applicable provisions of the FSMA will be complied with in respect to anything done in relation to the common stock in, from or otherwise involving the United Kingdom.

Switzerland

This document, as well as any other material relating to the shares which are the subject of the offering contemplated by this prospectus, do not constitute an issue prospectus pursuant to Article 652a and/or 1156 of the Swiss Code of Obligations. The shares will not be listed on the SIX Swiss Exchange and, therefore, the documents relating to the shares, including, but not limited to, this document, do not claim to comply with the disclosure standards of the listing rules of SIX Swiss Exchange and corresponding prospectus schemes annexed to the listing rules of the SIX Swiss Exchange. The shares are being offered in Switzerland by way of a private placement, i.e., to a small number of selected investors only, without any public offer and only to investors who do not purchase the shares with the intention to distribute them to the public. The investors will be individually approached by the issuer from time to time. This document, as well as any other material relating to the shares, is personal and confidential and does not constitute an offer to any other person. This document may only be used by those investors to whom it has been handed out in connection with the offering described herein and may neither directly nor indirectly be distributed or made available to other persons without express consent of the issuer. It may not be used in connection with any other offer and shall in particular not be copied and/or distributed to the public in (or from) Switzerland.

Hong Kong

The shares of our common stock offered hereby may not be offered or sold by means of any document other than (i) in circumstances which do not constitute an offer to the public within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), or (ii) to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap.571, Laws of Hong Kong) and any rules made thereunder, or (iii) in other circumstances which do not result in the document being a “prospectus” within the meaning of the Companies Ordinance (Cap.32, Laws of Hong Kong), and no advertisement, invitation or document relating to the shares may be issued or may be in the possession of any person for the purpose of issue (in each case whether in Hong Kong or elsewhere), which is directed at, or the contents of which are likely to be accessed or read by, the public in Hong Kong (except if permitted to do so under the laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to “professional investors” within the meaning of the Securities and Futures Ordinance (Cap. 571, Laws of Hong Kong) and any rules made thereunder.

Singapore

This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or invitation for subscription or

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purchase, of the shares of our common stock offered hereby may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor under Section 274 of the Securities and Futures Act, Chapter 289 of Singapore, or the SFA, (ii) to a relevant person, or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA.

Where the shares are subscribed or purchased under Section 275 by a relevant person which is: (i) a corporation (which is not an accredited investor) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor; or (ii) a trust (where the trustee is not an accredited investor) whose sole purpose is to hold investments and each beneficiary is an accredited investor, shares, debentures and units of shares and debentures of that corporation or the beneficiaries’ rights and interest in that trust shall not be transferable for 6 months after that corporation or that trust has acquired the shares under Section 275 except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person, or any person pursuant to Section 275(1A), and in accordance with the conditions, specified in Section 275 of the SFA; (2) where no consideration is given for the transfer; or (3) by operation of law.

Japan

The securities have not been and will not be registered under the Financial Instruments and Exchange Law of Japan (the Financial Instruments and Exchange Law) and each underwriter has agreed that it will not offer or sell any securities, directly or indirectly, in Japan or to, or for the benefit of, any resident of Japan (which term as used herein means any person resident in Japan, including any corporation or other entity organized under the laws of Japan), or to others for re-offering or resale, directly or indirectly, in Japan or to a resident of Japan, except pursuant to an exemption from the registration requirements of, and otherwise in compliance with, the Financial Instruments and Exchange Law and any other applicable laws, regulations and ministerial guidelines of Japan.

Dubai International Financial Centre

This prospectus relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority (“DFSA”). This prospectus is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus nor taken steps to verify the information set forth herein and has no responsibility for the prospectus. The securities to which this prospectus relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the securities offered should conduct their own due diligence on the securities. If you do not understand the contents of this prospectus you should consult an authorized financial advisor.

Australia

No placement document, prospectus, product disclosure statement or other disclosure document has been lodged with the Australian Securities and Investments Commission (“ASIC”), in relation to the offering. This prospectus does not constitute a prospectus, product disclosure statement or other disclosure document under the Corporations Act 2001 (the “Corporations Act”), and does not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act.

Any offer in Australia of the securities may only be made to persons (the “Exempt Investors”) who are “sophisticated investors” (within the meaning of section 708(8) of the Corporations Act), “professional investors” (within the meaning of section 708(11) of the Corporations Act) or otherwise pursuant to one or more exemptions contained in section 708 of the Corporations Act so that it is lawful to offer the securities without disclosure to investors under Chapter 6D of the Corporations Act.

161

The securities applied for by Exempt Investors in Australia must not be offered for sale in Australia in the period of 12 months after the date of allotment under the offering, except in circumstances where disclosure to investors under Chapter 6D of the Corporations Act would not be required pursuant to an exemption under section 708 of the Corporations Act or otherwise or where the offer is pursuant to a disclosure document which complies with Chapter 6D of the Corporations Act. Any person acquiring securities must observe such Australian on-sale restrictions.

This prospectus contains general information only and does not take account of the investment objectives, financial situation or particular needs of any particular person. It does not contain any securities recommendations or financial product advice. Before making an investment decision, investors need to consider whether the information in this prospectus is appropriate to their needs, objectives and circumstances, and, if necessary, seek expert advice on those matters.

162

LEGAL MATTERS

The validity of the common stock being offered will be passed upon for us by Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., Boston, Massachusetts. Simpson Thacher & Bartlett LLP, New York, New York, has acted as counsel for the underwriters in connection with certain legal matters related to this offering.

EXPERTS

The consolidated financial statements of Aspen Aerogels, Inc. as of December 31, 2012 and 2013, and for each of the years in the three-year period ended December 31, 2013, have been included herein and in the registration statement in reliance upon the report of KPMG LLP, independent registered public accounting firm, appearing elsewhere herein, and upon the authority of said firm as experts in accounting and auditing.

The audit report covering the December 31, 2013 consolidated financial statements contains an explanatory paragraph that states that the Company has suffered recurring losses and negative cash flows from operations, has a net capital deficiency, and has significant debt maturities that are payable within twelve months that raise substantial doubt about its ability to continue as a going concern. The consolidated financial statements do not include any adjustments that might result from the outcome of that uncertainty.

WHERE YOU CAN FIND MORE INFORMATION

We have filed with the SEC a registration statement on Form S-1 under the Securities Act with respect to the shares of our common stock to be sold in this offering. This prospectus, which constitutes part of the registration statement, does not include all of the information contained in the registration statement and the exhibits, schedules and amendments to the registration statement. Some items are omitted in accordance with the rules and regulations of the SEC. For further information with respect to us and our common stock, we refer you to the registration statement and to the exhibits and schedules to the registration statement filed as part of the registration statement. Statements contained in this prospectus about the contents of any contract or any other document filed as an exhibit are not necessarily complete and in each instance we refer you to the copy of the contract or other documents filed as an exhibit to the registration statement. Each of these statements is qualified in all respects by this reference.

You may read and copy the registration statement of which this prospectus is a part at the SEC’s public reference room, which is located at 100 F Street, N.E., Room 1580, Washington, D.C. 20549. You can request copies of the registration statement by writing to the SEC and paying a fee for the copying cost. Please call the SEC at 1-800-SEC-0330 for more information about the operation of the SEC’s public reference room. In addition, the SEC maintains an Internet website, located at www.sec.gov, which contains reports, proxy and information statements and other information regarding issuers that file electronically with the SEC. You may access the registration statement of which this prospectus is a part at the SEC’s Internet website.

Upon the closing of the offering, we will become subject to the full informational and periodic reporting requirements of the Exchange Act. We will fulfill our obligations with respect to such requirements by filing periodic reports and other information with the SEC. These documents will also be publicly available, free of charge, on our website, www.aerogel.com. We intend to furnish our stockholders with annual reports containing consolidated financial statements certified by an independent registered public accounting firm.

163

Aspen Aerogels, Inc.

Index To Consolidated Financial Statements

Report of Independent Registered Public Accounting Firm	F-2
Financial Statements:
Consolidated Balance Sheets as of December 31, 2012 and December 31, 2013	F-3
Consolidated Statements of Operations for the Years Ended December 31, 2011, 2012 and 2013	F-4
Consolidated Statements of Comprehensive Income (Loss) for the Years Ended December  31, 2011, 2012 and 2013	F-5
Consolidated Statements of Stockholders’ (Deficit) Equity for the Years Ended December  31, 2011, 2012 and 2013	F-6
Consolidated Statements of Cash Flows for the Years Ended December 31, 2011, 2012 and 2013	F-7
Notes to Consolidated Financial Statements	F-8

F-1

Report of Independent Registered Public Accounting Firm

The Board of Directors and Stockholders

Aspen Aerogels, Inc.:

We have audited the accompanying consolidated balance sheets of Aspen Aerogels, Inc. and subsidiaries as of December 31, 2012 and 2013, and the related consolidated statements of operations, comprehensive income (loss), stockholders’ (deficit) equity, and cash flows for each of the years in the three-year period ended December 31, 2013. These consolidated financial statements are the responsibility of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements based on our audits.

We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audits provide a reasonable basis for our opinion.

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of Aspen Aerogels, Inc. and subsidiaries as of December 31, 2012 and 2013, and the results of their operations and their cash flows for each of the years in the three-year period ended December 31, 2013, in conformity with U.S. generally accepted accounting principles.

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in note 1 to the consolidated financial statements, the Company has suffered recurring losses and negative cash flows from operations, has a net capital deficiency, and has significant debt maturities that are payable within twelve months that raise substantial doubt about its ability to continue as a going concern. Management’s plans in regard to these matters are also described in note 1. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

/s/ KPMG LLP

Boston, Massachusetts

March 25, 2014, except as to

Notes 1, 9 and 20,

which are as of April 28,

2014

F-2

ASPEN AEROGELS, INC.

Consolidated Balance Sheets

	December 31
	2012			2013
	(In thousands, except share and per share data)
Assets
Current assets:
Cash	$	1,343		$	1,574
Accounts receivable, net of allowance for doubtful accounts		14,162			18,971
Inventories		6,345			6,892
Prepaid expenses and other current assets		426			651
Total current assets		22,276			28,088
Property, plant and equipment, net		72,635			62,023
Other assets		390			331
Total assets	$	95,301		$	90,442
Liabilities, Redeemable Convertible Preferred Stock and Stockholders’ (Deficit) Equity
Current liabilities:
Subordinated notes, current portion	$	—		$	17,306
Convertible notes, current portion		—			435
Capital leases, current portion		43			75
Revolving line of credit		1,338			1,000
Accounts payable		9,082			7,114
Accrued expenses		2,727			5,023
Deferred revenue		1,183			595
Other current liabilities		6,771			—
Total current liabilities		21,144			31,548
Subordinated notes, excluding current portion		13,535			—
Senior convertible notes		—			28,135
Convertible notes, excluding current portion		95,088			91,439
Capital leases, excluding current portion		79			165
Other long-term liabilities		—			1,121
Total liabilities		129,846			152,408
Commitments and contingencies (Note 12)
Series B redeemable convertible preferred stock, $0.00001 par value; 1,601,053 shares authorized, issued and outstanding at December 31, 2012		29,935			—
Series A redeemable convertible preferred stock, $0.00001 par value; 5,284,347 shares authorized, issued and outstanding at December 31, 2012		56,315			—
Stockholders’ (deficit) equity:
Series C convertible preferred stock, $0.00001 par value; 116,024,242 shares authorized, 20,000 issued and outstanding at December 31, 2013		—			—
Series B convertible preferred stock, $0.00001 par value; 1,601,053 shares authorized, issued and outstanding December 31, 2013		—			—
Series A convertible preferred stock, $0.00001 par value; 5,284,347 shares authorized, issued and outstanding at December 31, 2013		—			—
Common stock, $0.00001 par value; 210,888,230 shares authorized, 2,623,156 shares issued and outstanding at December 31, 2012 and 2013		—			—
Additional paid-in capital		164,354			270,794
Accumulated deficit		(285,149	)		(332,760	)
Total stockholders’ (deficit) equity		(120,795	)		(61,966	)
Total liabilities, redeemable convertible preferred stock and stockholders’ (deficit) equity	$	95,301		$	90,442

See accompanying notes to consolidated financial statements.

F-3

ASPEN AEROGELS, INC.

Consolidated Statements of Operations

	Year Ended December 31
	2011			2012			2013
	(In thousands, except share and per share data)
Revenue:
Product	$	42,717		$	60,389		$	82,057
Research services		3,233			3,064			4,037
Total revenue		45,950			63,453			86,094
Cost of revenue:
Product		47,071			70,025			73,399
Research services		1,505			1,396			1,964
Gross profit (loss)		(2,626	)		(7,968	)		10,731
Operating expenses:
Research and development		4,085			5,142			5,159
Sales and marketing		5,565			8,564			9,271
General and administrative		8,291			11,299			12,833
Write-off of construction in progress		—			—			3,440
Total operating expenses		17,941			25,005			30,703
Income (loss) from operations		(20,567	)		(32,973	)		(19,972	)
Other income (expense):
Interest expense		(8,822	)		(21,790	)		(30,599	)
Gain on extinguishment of convertible notes		—			—			8,898
Loss on exchange of convertible notes		—			—			(5,697	)
Debt extinguishment costs		—			(1,379	)		—
Costs associated with postponed public offering		(3,443	)		—			(241	)
Total other income (expense), net		(12,265	)		(23,169	)		(27,639	)
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)
Net income (loss) attributable to common stockholders	$	(56,497	)	$	(8,941	)	$	1,338
Net income (loss) attributable to common stockholders per common share:
Basic	$	(21.66	)	$	(3.41	)	$	0.51
Diluted	$	(21.66	)	$	(3.41	)	$	0.49
Weighted-average common shares outstanding:
Basic		2,607,888			2,622,897			2,623,156
Diluted		2,607,888			2,622,897			2,722,947

See accompanying notes to consolidated financial statements.

F-4

ASPEN AEROGELS, INC.

Consolidated Statements of Comprehensive Income (Loss)

	Year Ended December 31
	2011			2012			2013
	(In thousands, except share and per share data)
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)
Other comprehensive income:
Realized gain on available-for-sale securities		(8	)		—			—
Comprehensive income (loss)	$	(32,840	)	$	(56,142	)	$	(47,611	)

See accompanying notes to consolidated financial statements.

F-5

ASPEN AEROGELS, INC.

Consolidated Statements of Stockholders’ (Deficit) Equity

(In thousands, except share and per share data)

	Series C convertible preferred stock $0.00001 Par Value				Series B convertible preferred stock $0.00001 Par Value				Series A convertible preferred stock $0.00001 Par Value				Common Stock $0.00001 Par Value				Additional Paid-in Capital			Accumulated Deficit			Accumulated Other Comprehensive Income (Loss)			Total Stockholders’ (Deficit) / Equity
	Shares		Value		Shares		Value		Shares		Value		Shares		Value
Balance at December 31, 2010		—	$	—		—	$	—		—	$	—		2,557,497	$	—	$	138,064		$	(196,175	)	$	8		$	(58,103	)
Net income (loss)		—		—		—		—		—		—		—		—		—			(32,832	)		—			(32,832	)
Realized gain on available-for-sale securities		—		—		—		—		—		—		—		—		—			—			(8	)		(8	)
Issuance of common stock		—		—		—		—		—		—		63,060		—		31			—			—			31
Stock compensation expense		—		—		—		—		—		—		—		—		1,064			—			—			1,064
Dividends on redeemable convertible preferred stock		—		—		—		—		—		—		—		—		(4,182	)		—			—			(4,182	)
Changes in redeemable convertible preferred stock to redemption value		—		—		—		—		—		—		—		—		(19,483	)		—			—			(19,483	)
Balance at December 31, 2011		—		—		—		—		—		—		2,620,557		—		115,494			(229,007	)		—			(113,513	)
Net income (loss)		—		—		—		—		—		—		—		—		—			(56,142	)		—			(56,142	)
Issuance of common stock		—		—		—		—		—		—		2,599		—		5			—			—			5
Stock compensation expense		—		—		—		—		—		—		—		—		1,654			—			—			1,654
Dividends on redeemable convertible preferred stock		—		—		—		—		—		—		—		—		(4,191	)		—			—			(4,191	)
Changes in redeemable convertible preferred stock to redemption value		—		—		—		—		—		—		—		—		51,392			—			—			51,392
Balance at December 31, 2012		—		—		—		—		—		—		2,623,156		—		164,354			(285,149	)		—			(120,795	)
Net income (loss)		—		—		—		—		—		—		—		—		—			(47,611	)		—			(47,611	)
Stock compensation expense		—		—		—		—		—		—		—		—		4,426			—			—			4,426
Dividends on redeemable convertible preferred stock		—		—		—		—		—		—		—		—		(996	)		—			—			(996	)
Changes in redemption value of redeemable convertible preferred stock at extinguishment		—		—		—		—		—		—		—		—		86,161			—			—			86,161
Reclassification of redeemable convertible preferred stock from temporary to permanent equity		—		—		1,601,053		—		5,284,347		—		—		—		1,085			—			—			1,085
Issuance of Series C convertible preferred stock		20,000		—		—		—		—		—		—		—		—			—			—			—
Issuance of Series C preferred stock warrants, net of issuance costs		—		—		—		—		—		—		—		—		15,764			—			—			15,764
Balance at December 31, 2013		20,000	$	—		1,601,053	$	—		5,284,347	$	—		2,623,156	$	—	$	270,794		$	(332,760	)	$	—		$	(61,966	)

See accompanying notes to consolidated financial statements.

F-6

ASPEN AEROGELS, INC.

Consolidated Statements of Cash Flows

	Year Ended December 31
	2011			2012			2013
	(In thousands)
Cash flows from operating activities:
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization		7,521			9,684			10,061
Write-off of construction in progress		—			—			3,440
Loss on disposal of assets		—			2,489			230
Debt issuance costs and noncash interest expenses		3,519			2,959			998
Write-off of costs associated with postponed public offering		3,443			—			241
Write-off of costs associated with loan application		564			—			—
Accretion of debt to fair value		4,752			18,678			18,696
Gain on extinguishment of convertible notes		—			—			(8,898	)
Loss on exchange of convertible notes		—			—			5,697
Issuance of Series C preferred stock warrants in connection with senior convertible notes		—			—			10,677
Stock compensation expense		1,064			1,654			4,426
Loss on extinguishment of debt		—			1,379			—
Provision for accounts receivable		92			—			—
Other		(26	)		(2	)		(25	)
Changes in operating assets and liabilities:
Accounts receivable		2,871			(6,796	)		(4,809	)
Inventories		(7,269	)		3,177			(547	)
Prepaid expenses and other assets		(50	)		(2	)		(287	)
Accounts payable		(708	)		1,676			(1,686	)
Accrued expenses		(749	)		1,086			2,297
Deferred revenue		455			281			(588	)
Other liabilities		(6,800	)		(6,000	)		(6,000	)
Net cash used in operating activities		(24,153	)		(25,879	)		(13,688	)
Cash flows from investing activities:
Capital expenditures		(36,304	)		(10,236	)		(3,329	)
Decrease in restricted cash		406			451			—
Proceeds from maturities and sales of marketable securities		4,026			—			—
Net cash used in investing activities		(31,872	)		(9,785	)		(3,329	)
Cash flows from financing activities:
Borrowings under line of credit		2,000			25,515			19,929
Repayments under line of credit		(2,000	)		(24,177	)		(20,267	)
Proceeds from issuance of long-term debt		45,000			24,890			18,500
Repayment of borrowings under long-term debt		(247	)		—			—
Financing costs		(843	)		(425	)		(872	)
Deferred offering costs		(3,443	)		—			—
Repayment of obligations under capital lease		(32	)		(42	)		(42	)
Proceeds from issuance of common stock		31			5			—
Net cash provided by financing activities		40,466			25,766			17,248
Net (decrease) increase in cash		(15,559	)		(9,898	)		231
Cash at beginning of period		26,800			11,241			1,343
Cash at end of period	$	11,241		$	1,343		$	1,574
Supplemental disclosures of cash flow information:
Interest paid	$	608		$	152		$	228
Income taxes paid	$	—		$	—		$	—
Supplemental disclosures of non-cash activities:
Accrued dividends on preferred stock	$	4,182		$	4,191		$	996
Changes in redemption value of redeemable convertible preferred stock	$	19,483		$	(51,392	)	$	(86,161	)
Reclassification of redeemable convertible preferred stock from temporary to permanent equity	$	—		$	—		$	(1,085	)
Changes in accrued capital expenditures	$	(1,000	)	$	(38	)	$	(523	)
Capitalized interest	$	1,650		$	2,270		$	70
Capital lease	$	124		$	—		$	160

See accompanying notes to consolidated financial statements.

F-7

ASPEN AEROGELS, INC.

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS

(1) Description of Business

Nature of Business

Aspen Aerogels, Inc. (the Company) is an energy technology company that designs, develops and manufactures innovative, high-performance aerogel insulation. The Company also conducts research and development related to aerogel technology supported by funding from several agencies of the U.S. government and other institutions in the form of research and development contracts.

The Company’s predecessor was incorporated in Delaware on May 4, 2001, and the Company maintains its corporate offices in Northborough, Massachusetts. The Company owns two wholly owned subsidiaries: Aspen Aerogels Rhode Island, LLC and Aspen Aerogels Germany, GmbH.

Liquidity

These consolidated financial statements have been prepared assuming the Company will continue as a going concern. The Company has incurred operating losses and negative cash flow from operations since inception, has an accumulated deficit of $332.8 million as of December 31, 2013 and has substantial ongoing cash flow commitments, including debt maturities totaling $19.8 million due in September 2014 and $0.5 million due in December 2014. The Company has invested significant resources to commercialize aerogel technology and to build a manufacturing infrastructure capable of supplying aerogel products at the volumes and costs necessary to meet the anticipated future demand of its customers. The Company markets a set of commercially viable products and serves a growing base of customers.

In December 2010, the Company issued Subordinated Notes generating gross proceeds of $10.0 million (see note 6). In March 2011, the Company entered into a $10.0 million line of credit agreement which provided $8.6 million in borrowing capacity due to a borrowing limitation under the terms of the credit facility. Of that amount, $1.0 million was drawn and letters of credit of $1.2 million were outstanding at December 31, 2013 (see note 9). Commencing in June 2011 and continuing through October 2012, the Company also issued Convertible Notes generating aggregate gross proceeds of $65.9 million. The Company also issued an additional $4.0 million of Convertible Notes in November 2012 and $3.5 million of Convertible Notes in January 2013 (see notes 7 and 8).

In March 2013, the Company entered into an agreement authorizing the issuance of $22.5 million in Senior Convertible Notes (see note 7). As part of the financing, existing note holders exchanged the $7.5 million of Convertible Notes issued in November 2012 and January 2013 for an equivalent principal value of Senior Convertible Notes. In addition, the Company issued Senior Convertible Notes generating gross proceeds of $15.0 million in March and May 2013. In total, the Company generated gross proceeds of $18.5 million from the issuance of Convertible Notes and Senior Convertible Notes during 2013.

In conjunction with the March 2013 financing, the Company also executed an amendment to its Subordinated Note and Warrant Purchase Agreement to extend the maturity date of the Subordinated Notes to September 30, 2014.

These sources of liquidity were used (i) to complete construction of a second production line and to acquire long lead-time equipment for a third line in the Company’s East Providence, Rhode Island manufacturing facility, (ii) to fund losses from operations, (iii) to fund investment in working capital to support revenue growth, (iv) to fund capital expenditures to improve the efficiency and throughput of existing manufacturing assets, and (v) to repay all obligations in full under the Company’s cross license agreement with Cabot Corporation (see note 10).

F-8

The Company incurred a significant increase in manufacturing expense associated with the operation of the second production line for the years ended December 31, 2011 and 2012 which contributed to gross losses during the period. Strong demand for the Company’s products, increasing production levels and improved manufacturing productivity contributed to gross profit and improving cash flow from operations for the year ended December 31, 2013.

The Company’s current financial forecasts anticipate continued revenue growth, increasing gross profit and improving cash flow from operations for the year ending December 31, 2014. In addition, the Company has cash of $1.6 million and $6.4 million available under its revolving line of credit at December 31, 2013.

The Company’s line of credit agreement was to expire on June 27, 2014 and the Company is required to repay $19.8 million upon maturity of the Subordinated Notes on September 30, 2014. The Company has amended its line of credit agreement which extended the maturity date of the facility to July 27, 2014 (see note 20). In addition, the Company has capital commitments of $0.6 million at December 31, 2013. While the Company has actions within its control to execute cost reduction measures to improve cash flow from operations during 2014, these measures would not be sufficient to generate the funds required to repay the Subordinated Notes upon maturity and repay amounts anticipated to be outstanding on the line of credit at expiration.

In response, the Company is actively pursuing sources of financing to replace the Subordinated Notes and line of credit upon maturity. These sources could include an initial public offering (IPO) of the Company’s common stock, refinancing of the Subordinated Notes prior to maturity, renewal and extension of the line of credit, and additional issuances of debt or equity to new or existing investors. However, given that these financing alternatives are not within the control of the Company and are events not certain to occur, the scheduled maturity of the Subordinated Notes during 2014 and the expiration of the line of credit raise substantial doubt regarding the Company’s ability to continue as a going concern. The failure by the Company to repay amounts due upon maturity would constitute an event of default under the terms of its existing credit facilities and debt agreements, and would have an adverse impact on the Company’s ability to continue operations and to achieve its intended business objectives.

The consolidated financial statements do not include any adjustments to reflect the possible future effects on the recoverability of assets or amounts and classification of liabilities that may result from the outcome of the Company’s ability to continue as a going concern.

(2) Summary of Basis of Presentation and Significant Accounting Policies

Principles of Consolidation

The accompanying consolidated financial statements, which have been prepared in accordance with generally accepted accounting principles in the United States of America, include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation.

Reverse Stock Split

On August 20, 2013, the Company completed a 1-for-10 reverse stock split of its capital stock. All shares and per share amounts in the financial statements and footnotes have been adjusted retroactively to reflect the effects of this action.

Use of Estimates

The preparation of the consolidated financial statements requires the Company to make a number of estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. Significant items subject to such estimates and assumptions include allowances for doubtful accounts, inventory valuation, the carrying amount of property and equipment, fair value of debt and capital stock, stock-based compensation and deferred income taxes. The Company evaluates its estimates and assumptions on an on-going basis using

F-9

historical experience and other factors, including the current economic environment, which it believes to be reasonable under the circumstances. Management adjusts such estimates and assumptions when facts and circumstances dictate. Illiquid credit markets, volatile equity markets and declines in business investment increase the uncertainty inherent in such estimates and assumptions. As future events and their effects cannot be determined with precision, actual results could differ significantly from these estimates. Changes in these estimates resulting from continuing changes in the economic environment will be reflected in the financial statements in future periods.

Cash

Cash balances are maintained with major financial institutions in North America. Deposits with these financial institutions may exceed the amount of insurance provided on such deposits.

Fair Value of Financial Instruments

Fair value is an exit price that represents the amount that would be received from the sale of an asset or paid to transfer a liability in an orderly transaction between market participants. Accordingly, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability. The Company discloses the manner in which fair value is determined for assets and liabilities based on a three-tiered fair value hierarchy. The hierarchy ranks the quality and reliability of the information used to determine the fair values. The three levels of inputs described in the standard are:

Level 1: Quoted prices in active markets for identical assets or liabilities.

Level 2: Observable inputs, other than Level 1 prices, for the assets or liabilities, either directly or indirectly, for substantially the full term of the assets or liabilities.

Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

Under the Fair Value Option Subsections of Financial Accounting Standards Board (FASB) ASC Subtopic 825-10, Financial Instruments — Overall, the Company has the irrevocable option to report most financial assets and financial liabilities at fair value on an instrument by instrument basis, with changes in fair value reported in earnings each reporting period. As a result of electing this option, the Company records its Subordinated Notes, Senior Convertible Notes and Convertible Notes at fair value in order to measure these liabilities at amounts that more accurately reflect the economics of these instruments (see notes 6, 7 and 8).

At December 31, 2013, the Company’s Subordinated Notes, Senior Convertible Notes and Convertible Notes were valued utilizing Level 3 inputs. At December 31, 2012, the Company’s Redeemable Convertible Preferred Stock, Subordinated Notes and Convertible Notes were valued utilizing Level 3 inputs.

Concentration of Credit Risk

Financial instruments, which potentially expose the Company to concentrations of credit risk, consist principally of accounts receivable. The Company’s customers consist primarily of insulation distributors and contractors located throughout the world. The Company performs ongoing credit evaluations of its customers’ financial condition and generally requires no collateral to secure accounts receivable. The Company maintains an allowance for doubtful accounts based on its assessment of the collectability of accounts receivable. The Company reviews the allowance for doubtful accounts quarterly. The Company has not experienced any meaningful non-payment or write-offs of accounts receivable. Accordingly, the allowance for doubtful accounts was zero at December 31, 2012 and 2013. The Company does not have any off-balance-sheet credit exposure related to its customers.

F-10

For the year ended December 31, 2011, two customers represented 13% and 10% of total revenue, respectively. For the year ended December 31, 2012, one customer represented 13% of total revenue and for the year ended December 31, 2013, two customers represented 15% and 11% of total revenue, respectively.

At December 31, 2012, the Company had two customers that accounted for 13% and 10% of accounts receivable, respectively. At December 31, 2013, the Company had three customers that accounted for 20%, 14% and 11% of accounts receivable, respectively.

Inventories

Inventory consists of finished products and raw materials. Inventories are carried at lower of cost, determined using the first-in, first-out (FIFO) method, or market. Cost includes materials, labor and manufacturing overhead. Manufacturing overhead is allocated to the costs of conversion based on normal capacity of the Company’s production facility. Abnormal freight, handling costs and material waste is expensed in the period it occurs.

The Company periodically reviews its inventories and makes provisions as necessary for estimated excess, obsolete or damaged goods to ensure values approximate the lower of cost or market. The amount of any such provision is equal to the difference between the cost of inventory and the estimated market value based upon assumptions about future demand, selling prices and market conditions.

Property, Plant and Equipment, Net

Property, plant and equipment are stated at cost. Assets held under capital leases are stated at the lesser of the present value of future minimum payments, using the Company’s incremental borrowing rate or the fair value of the property at the inception of the lease. Expenditures for maintenance and repairs are charged to expense as incurred, whereas major betterments are capitalized as additions to property, plant and equipment.

Interest expense capitalization commences at the time a capital project begins construction and concludes when the project is completed. The Company has capitalized interest costs as part of the historical cost of constructing its manufacturing facilities. The Company capitalized $1.7 million, $2.3 million and $0.1 million in interest costs related to the build-out of the East Providence facility during the years ended December 31, 2011, 2012 and 2013, respectively.

Depreciation on plant and equipment is calculated on the straight-line method over the estimated useful lives of the assets. Assets related to capital leases are amortized on a straight-line basis over the shorter of the lease term or estimated useful life of the asset.

Assets utilized in the Company’s operations that are taken out of service with no future use are charged to cost of sales or operating expenses, depending on the department in which the asset was utilized. Write-offs of construction in progress or abandonments are charged to operating expenses upon the determination of no future use.

Other Assets

Other assets primarily include long-term deposits and patent costs. Patent costs are amortized over the life of the patent.

Impairment of Long-Lived Assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. Recognition and measurement of a potential impairment is performed on assets grouped with other assets and liabilities at the lowest level where identifiable cash flows are largely independent of the cash flows of other assets and liabilities. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset or asset group to future undiscounted net cash flows expected to be generated by the asset or asset group. If the carrying amount of

F-11

an asset or asset group exceeds its estimated undiscounted future cash flows, an impairment charge is recognized for the amount by which the carrying amount of the asset or asset group exceeds the fair value of the asset or asset group. Fair value is determined through various valuation techniques including discounted cash flows models, quoted market values and third-party independent appraisals, as considered necessary.

Asset Retirement Obligations

The Company records asset retirement obligations associated with its lease obligations and the retirement of tangible long-lived assets. The Company reviews legal obligations associated with the retirement of long-lived assets that result from contractual obligations or the acquisition, construction, development and/or normal use of the assets. If it is determined that a legal obligation exists, regardless of whether the obligation is conditional on a future event, the fair value of the liability for an asset retirement obligation is recognized in the period in which it is incurred, if a reasonable estimate of fair value can be made. An amount equal to the fair value of the liability is also recorded as a long-term asset that is depreciated over the estimated life of the asset. The difference between the gross expected future cash outflow and its present value is accreted over the life of the related lease as an operating expense.

Deferred Revenue

The Company records deferred revenue for product sales when (i) the Company has delivered products but other revenue recognition criteria have not been satisfied or (ii) payments have been received in advance of products being delivered.

Redeemable Convertible Preferred Stock

The Company’s Series A and Series B redeemable convertible preferred stock were classified as temporary equity and shown net of issuance costs at December 31, 2012. The Company recognized changes in the redemption value and adjusted the carrying amount of the redeemable convertible preferred stock to equal the redemption value at the end of each reporting period.

The Company accounted for the 2013 amendment to its certificate of incorporation, changing the terms of its redeemable convertible preferred stock, as an extinguishment as the fair value of the shares immediately after the amendment was significantly different from the fair value of the instrument immediately before the amendment. The change in fair value upon extinguishment was recorded in additional paid-in capital (see note 13).

Accumulated Other Comprehensive Income

Accumulated other comprehensive income (loss) consisted of the recognition of unrealized gains on the sale of available-for-sale securities during the year ended December 31, 2011.

Revenue Recognition

The Company recognizes revenue from the sale of products and delivery of research and development services. Revenue is recognized when all of the following criteria are met: persuasive evidence of an arrangement exists, the price to the buyer is fixed or determinable, delivery has occurred or services have been provided, and collectability is reasonably assured.

Product Revenue

Product revenue is generally recognized upon transfer of title and risk of loss, which is generally upon shipment or delivery. The Company’s customary shipping terms are free on board (FOB) shipping point; however, some products are shipped using FOB destination shipping terms. Revenue associated with products shipped FOB destination is recognized when the products reach their specified destination. Products are typically delivered without significant post-sale obligations to customers.

F-12

The Company provides warranties for its products and records the estimated cost within cost of sales in the period that the related revenue is recorded. The Company’s standard warranty period extends one to two years from the date of sale, depending on the type of product purchased. The warranties provide that the Company’s products will be free from defects in material and workmanship, and will, under normal use, conform to the specifications for the product. For the years ended December 31, 2011, 2012 and 2013, warranty claims and charges have been insignificant.

Sales returns are recorded based on known sales and return information. Products that exhibit unusual sales return patterns due to quality or other manufacturing matters are specifically investigated and analyzed as part of the sales return accrual. The sales return accrual represent a reserve for products that may be returned due to quality concerns or authorized for destruction in the field. Sales return reserves are recorded at full original sales value. The Company rarely exchanges products from inventory for returned products. Sales return reserves were $0.4 million and $0.2 million at December 31, 2012 and 2013, respectively.

Research Services Revenue

The Company performs research services under contracts with various government agencies and other institutions. The Company records revenue earned on research services contracts using the percentage-of-completion method in two ways: (1) for firm-fixed-price contracts, the Company accrues that portion of the total contract price that is allocable, on the basis of the Company’s estimates of costs incurred to date to total contract costs; (2) for cost-plus-fixed-fee contracts, the Company records revenue that is equal to total payroll cost incurred times a stated factor plus reimbursable expenses, to a stated upper limit. The primary cost is the labor effort expended in completing research and the only deliverable other than the labor hours expended is reporting of research results to the customer. Because the input measure of labor hours expended is also reflective of the output measure, it is a reliable means to measure the extent of progress towards completion. Revisions in cost estimates and fees during the course of the contract are reflected in the accounting period in which the facts that require the revisions become known.

Provision is made for the entire amount of future estimated losses on contracts when the current contract estimate is a loss while claims for additional contract compensation are not reflected in the accounts until the year in which such claims are identifiable and receipt is probable. Contract costs and rates used to allocate overhead to contracts are subject to audit by the respective contracting government agency. Adjustments to revenue as a result of audit are recorded in the period they become known. Adjustments to revenue as a result of audit have been insignificant.

Shipping and Handling Costs

Shipping and handling costs are classified as a component of cost of revenue. Customer payments of shipping and handling costs are recorded as product revenue.

Stock-based Compensation

Stock-based compensation cost is measured at the grant date based on the fair value of the award. Expense is recognized on a straight-line basis over the requisite service period for all awards with service conditions. For performance-based awards, the grant date fair value is recognized as expense when the condition is probable of being achieved, and then on a graded basis over the requisite service period. The Company uses the Black-Scholes option-pricing model to determine the fair value of service-based awards, which requires a number of complex and subjective assumptions including fair value of the underlying security, the expected volatility of the underlying security, a risk-free interest rate, the expected term of the option and the forfeiture rate. For performance-based stock options issued during the year ended December 31, 2013, the Company used a Monte Carlo simulation model to estimate the number of options the Company expects to remain outstanding and eligible for vesting upon completion of an IPO. The simulation model was based on a number of complex assumptions including the terms of

F-13

the performance condition, the value of the Company’s common stock at the time of its IPO, the expected time from the date of grant to its IPO, and expected volatility. The compensation cost of these performance-based options was determined by multiplying the Black-Scholes estimate of grant date fair value by the percentage of options expected to remain outstanding and eligible for vesting upon completion of the Company’s IPO. The Company engaged a third party independent valuation specialist to assist the Company in estimating the fair value of the underlying securities for all stock-based awards issued in 2011, 2012 and 2013.

Stock-based compensation is included in cost of sales or operating expenses, as applicable, and consists of the following:

	Year Ended December 31
	2011		2012		2013
	(In thousands)
Product cost of revenue	$	195	$	221	$	496
Research and development expenses		111		112		267
Sales and marketing expenses		164		384		727
General and administrative expenses		594		937		2,936
Total stock-based compensation	$	1,064	$	1,654	$	4,426

Research and Development

Costs incurred in the research and development of the Company’s products are expensed as incurred and include compensation and related costs, services provided by third-party contractors, materials and supplies and are classified as research and development expenses. Research and development costs directly associated with research services revenue are classified as research services in cost of revenue.

Earnings Per Share

Net income (loss) per common share is calculated using the two-class method, which is an earnings allocation formula that determines net income (loss) per share for the holders of the Company’s common shares and participating securities. All series of preferred stock and the Series C preferred stock warrants contain participation rights in any dividend to be paid by the Company to holders of its common shares and are deemed to be participating securities. Net income (loss) available to common shareholders and participating securities is allocated to each share on an as-if-converted basis as if all of the earnings for the period had been distributed. The participating securities do not include a contractual obligation to share in losses of the Company and are not included in the calculation of net loss per share in the periods that have a net loss.

Diluted net income (loss) per share is computed using the more dilutive of (a) the two-class method, or (b) the if-converted method. The Company allocates net income (loss) first to preferred stockholders and holders of warrants to purchase preferred stock based on dividend rights and then to common, preferred stockholders and preferred warrant holders based on ownership interests. The weighted-average number of common shares included in the computation of diluted net income (loss) gives effect to all potentially dilutive common equivalent shares, including outstanding stock options and warrants. Common equivalent shares are excluded from the computation of diluted net income (loss) per share if their effect is antidilutive.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to

F-14

taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date.

The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. The Company accounts for uncertain tax positions using a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. Differences between tax positions taken in a tax return and amounts recognized in the financial statements are recorded as adjustments to income taxes payable or receivable, or adjustments to deferred taxes, or both. Changes in recognition or measurement are reflected in the period in which the change in judgment occurs. The Company recognizes penalties and interest related to uncertain tax positions, if any, as a component of income tax expense.

Segments

Operating segments are identified as components of an enterprise about which separate, discrete financial information is available for evaluation by the chief operating decision maker in making decisions on how to allocate resources and assess performance. The Company’s chief operating decision maker is the Chief Executive Officer. The Company’s chief operating decision maker reviews consolidated operating results to make decisions about allocating resources and assessing performance for the entire Company. The Company views its operations and manages its business as one operating segment.

Information about the Company’s revenues, based on shipment destination or research services location, is presented in the following table:

	Year Ended December 31
	2011		2012		2013
	(In thousands)
Revenue:
U.S.		15,182		19,909		30,164
International		30,768		43,544		55,930
	$	45,950	$	63,453	$	86,094

Recently Issued Accounting Standards

Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists

In July 2013, the FASB issued Accounting Standards Update (ASU) 2013-11, Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (ASU 2013-11). The amendments in ASU 2013-11 require an entity to present an unrecognized tax benefit in the financial statements as a reduction to a deferred tax asset for a net operating loss (NOL) carryforward, a similar tax loss or a tax credit carryforward except when: (1) an NOL carryforward, a similar tax loss or a tax credit carryforward is not available as of the reporting date under the governing tax law to settle taxes that would result from the disallowance of the tax position; or (2) the entity does not intend to use the deferred tax asset for this purpose (provided that the tax law permits a choice). If either of these conditions exists, an entity should present an unrecognized tax benefit in the financial statements as a liability and should not net the unrecognized tax benefit with a deferred tax asset. The amendments in this ASU are effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The amendments should be applied prospectively to all unrecognized tax benefits that exist at the effective date. Retrospective application is permitted. The adoption of this guidance will not have any impact on the Company’s consolidated financial statements.

F-15

Presentation of Amounts Reclassified Out of Accumulated Other Comprehensive Income

In February 2013, the FASB issued guidance for reporting of amounts reclassified out of accumulated other comprehensive income. The revised guidance requires reporting the effect of significant reclassifications out of accumulated other comprehensive income on the respective line items in net income if the amount being reclassified is required to be reclassified in its entirety to net income. For other amounts that are not required to be reclassified in their entirety to net income in the same reporting period, an entity is required to cross-reference other disclosures that provide additional detail about these amounts. The amendments do not change the current requirements for reporting net income or other comprehensive income in financial statements. The guidance was effective prospectively for reporting periods beginning after December 15, 2012. Early adoption was permitted. The adoption of this guidance did not have any impact on the Company’s consolidated financial statements.

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that are adopted by the Company as of the specified effective date.

(3) Inventories

Inventories consist of the following:

	December 31
	2012		2013
	(In thousands)
Raw material	$	2,803	$	2,813
Finished goods		3,542		4,079
Total	$	6,345	$	6,892

(4) Property, Plant and Equipment, Net

Property, plant and equipment consist of the following:

	December 31
	2012			2013			Useful life
	(In thousands)
Construction in progress	$	13,400		$	6,177		—
Buildings		16,224			16,303		30 years
Machinery and equipment		74,822			77,466		5 — 10 years
Computer equipment and software		4,754			5,298		3 years
Total		109,200			105,244
Accumulated depreciation and amortization		(36,565	)		(43,221	)
Property, plant and equipment, net	$	72,635		$	62,023

Plant and equipment under capital leases consist of the following:

	December 31
	2012			2013
	(In thousands)
Office equipment, at cost	$	94		$	113
Vehicles, at cost		197			288
Total capital leases		291			401
Accumulated amortization		(177	)		(178	)
Capital leases, net	$	114		$	223

F-16

Depreciation expense was $7.4 million, $9.6 million and $10.0 million for the years ended December 31, 2011, 2012 and 2013, respectively. Amortization associated with assets under capital leases was less than $0.1 million, for the years ended December 31, 2011, 2012 and 2013.

During the fourth quarter of 2012, certain equipment related to the Company’s manufacturing operations in the East Providence facility was taken out of service with no future alternative use. The remaining carrying value of the equipment of $2.5 million was charged to cost of sales.

During the fourth quarter of 2013, the Company completed its 2014 operating plan, which contemplated alternatives to complete the build out of the East Providence facility. In conjunction with this process, the Company performed an assessment of on-hand, long-lead time equipment for the third production line and determined that certain costs and partially completed assets had no future alternative use. As a result, the Company recorded a write-off of construction in progress totaling $3.4 million, inclusive of $0.4 million of capitalized interest, for the year ended December 31, 2013. In addition, $2.3 million was identified as having an alternative use as spare parts for the existing production lines.

Construction in progress totaling $13.4 million and $6.2 million, at December 31, 2012 and 2013, respectively, related primarily to capital projects at the East Providence facility.

(5) Accrued Expenses

Accrued expenses consist of the following:

	December 31
	2012		2013
	(In thousands)
Employee compensation and related taxes	$	1,481	$	3,926
Professional fees		236		200
Sales return reserve		421		209
Other accrued expenses		589		688
	$	2,727	$	5,023

(6) Subordinated Notes

Subordinated Notes consists of the following:

	December 31
	2012		2013
	(In thousands)
Subordinated Notes	$	13,535	$	17,306
Current maturities of Subordinated Notes		—		(17,306	)
Subordinated Notes, excluding current portion	$	13,535	$	—

On December 29, 2010, the Company issued 12% Secured Subordinated Promissory Notes (the Subordinated Notes) for aggregate proceeds of $10.0 million with an original maturity date of December 29, 2015. The proceeds were used to fund the expansion of a second manufacturing line at the East Providence facility. The Subordinated Notes are collateralized by certain of the Company’s assets at the East Providence facility.

All accrued interest on the Subordinated Notes is compounded semi-annually and added to principal on June 30th and December 31st of each year. Accrued and unpaid interest on the Subordinated Notes will be due and payable at maturity. The Subordinated Notes are subject to certain financial covenants, which include a

F-17

minimum tangible net worth calculation. As of December 31, 2013, the Company was in compliance with all financial covenants of the Subordinated Notes.

In conjunction with the financing, the Company issued 149,611 detachable stock warrants to purchase the Company’s common stock at $0.01 per share. The warrants are immediately exercisable and expire on December 29, 2017. The Company determined that the warrants, which are subject to net share settlement, are equity classified. A portion of the debt proceeds totaling $2.2 million was allocated to the warrants based on the estimated fair value of the warrants using the Black Scholes option pricing model and the following assumptions: (i) risk free interest rate of 2.75%, (ii) life of 7.5 years, (iii) volatility of 50%, and (iv) expected dividend yield of zero. The debt discount was being amortized to interest expense utilizing the effective interest rate method over the term of the Subordinated Notes.

The Company executed several amendments to the Subordinated Notes prior to September 26, 2012, in which the maturity date of the Subordinated Notes was changed to March 2, 2014 and the interest rate was increased to 12.75% and then to 15% per annum. The Company determined that these amendments were not substantial and represented modifications at the respective amendment dates.

In connection with the issuances of the Convertible Notes on September 26, 2012, the terms of the Subordinated Notes were amended (i) to increase the interest rate to 20% per annum and (ii) to add a premium which provides each note holder with additional interest equal to the amount of interest that would have accrued to the date of the amendment if the notes had provided interest at a rate of 20% per annum on the original principal amount and from the initial date of issuance. The applicable premium of $1.4 million of additional interest is due upon maturity. In conjunction with the Company’s March 2013 financing (see note 7), the Company further amended the terms of the Subordinated Notes to extend the maturity date to September 30, 2014.

The Company determined that the present value of the cash flow pursuant to the Subordinated Notes, as amended on September 26, 2012, was more than 10% greater than the remaining cash flow pursuant to the notes prior to the amendment. Accordingly, the Company accounted for the amendment as an extinguishment and reissuance of new Subordinated Notes. The Company recorded a $1.4 million loss associated with the extinguishment, which represents the difference between the carrying value of the original Subordinated Notes and the fair value of the new Subordinated Notes.

Subsequent to the extinguishment and upon reissuance of the Subordinated Notes, the Company elected the fair value option for the Subordinated Notes and records the instrument at fair value. The fair value of the Subordinated Notes is determined by analysis of the amount to be paid on the notes at the occurrence of certain events in which the Subordinated Notes would be repaid to the noteholders in cash. The probability weighted discounted cash flow analysis utilized assumptions related to the probability of the occurrence of each of the various events and appropriate discount rates for each of the scenarios.

At December 31, 2012 the valuations were calculated at an implied discount of approximately 31% and were weighted as follows: repayment prior to maturity on June 30, 2013, 65%; and repayment at maturity on September 30, 2014, 35%. There would not be a material difference if the weightings were increased or decreased by 10%. At December 31, 2012, the aggregate fair value of the Subordinated Notes was determined to be $13.5 million, with an aggregate unpaid principal balance totaling $13.1 million.

At December 31, 2013 the valuations were calculated at an implied discount of approximately 20% and were weighted as follows: repayment prior to maturity on June 30, 2014, 20%; and repayment at maturity on September 30, 2014, 80%. There would not be a material difference if the weightings were increased or decreased by 10%. At December 31, 2013, the aggregate fair value of the Subordinated Notes was determined to be $17.3 million, with an aggregate unpaid principal balance totaling $15.9 million.

F-18

The following table presents a roll-forward of the fair value of Level 3 (significant unobservable inputs) Subordinated Notes for the years ended December 31, 2012 and 2013:

Balance at December 31, 2011	$	0
Transfer into Level 3 on September 26, 2012 (1)		12,435
Change in fair value included in interest expense		1,100
Balance at December 31, 2012		13,535
Change in fair value included in interest expense		3,771
Balance at December 31, 2013	$	17,306

(1) Fair value option election was made on September 26, 2012.

Interest expense, inclusive of changes in fair value and amortization of deferred financing costs, related to the Subordinated Notes for the years ended December 31, 2011, 2012 and 2013 was $1.9 million, $2.9 million and $3.8 million, respectively. Of these totals, $0.7 million, $0.3 million and $0.0 million have been capitalized as part of the costs of the second production line at the Company’s East Providence facility for the years ended December 31, 2011, 2012 and 2013, respectively (see note 10).

(7) Senior Convertible Notes

Senior Convertible Notes consist of the following:

	December 31
	2012		2013
	(In thousands)
March 2013 Investor Notes	$	—	$	24,482
March 2013 Arcapita Notes		—		3,653
Total Senior Convertible Notes	$	—	$	28,135

Effective March 28, 2013, the Company entered into a Note and Warrant Purchase Agreement (March 2013 NPA) authorizing the issuance of $22.5 million of Senior Subordinated Convertible Notes (the March 2013 Investor Notes) and Senior Subordinated Arcapita Notes (the March 2013 Arcapita Notes) (collectively, the Senior Convertible Notes). At each closing under the March 2013 NPA, the Company issued warrants to purchase shares of a newly created Series C Preferred Stock (the Series C) based on the principal balance of Senior Convertible Notes issued to each purchaser. The Company determined that the Series C warrants, which are subject to net share settlement, are equity classified. Collectively, the warrants issued pursuant to the March 2013 NPA were exercisable for Series C shares equal to 85.7% of the then outstanding capital stock of the Company on a fully diluted basis. The warrants have an exercise price of $0.0001 per share, are immediately exercisable and expire on March 28, 2023.

The March 2013 Investor Notes bear interest at a rate of 8% per annum compounded annually and added to principal on December 31^st of each year. Accrued and unpaid interest will be payable upon maturity or on the date of any prepayment. Accrued interest is payable in cash at the time of payment of principal or converted with the outstanding principal amount into common shares of the Company upon an IPO. Upon maturity, the Company will be required to pay 1.375 times the aggregate principal amount and accrued interest on the March 2013 Investor Notes then outstanding or $33.8 million on March 28, 2016.

The March 2013 Arcapita Notes are non-interest-bearing and are due on March 28, 2016. The March 2013 Arcapita Notes include an option to purchase one share of nonparticipating preferred stock, as defined, on the maturity date. This preferred stock will be senior to all other series of the Company’s outstanding convertible preferred stock and have a liquidation preference totaling $5.2 million at maturity. If this option were to be exercised, the Company would create a new series of preferred stock that is currently not authorized.

F-19

In the event of an IPO, the outstanding principal and accrued interest of the March 2013 Investor Notes are subject to automatic conversion into shares of the Company’s common stock at the applicable Conversion Price. The Conversion Price is defined as the price per share of common stock paid by purchasers in the IPO multiplied by the Conversion Percentage. The Conversion Percentage is defined as 75.0% prior to the first anniversary of the convertible notes issuance or 62.5% on or after the first anniversary of the convertible notes issuance. The Company may not prepay the March 2013 Investor Notes without the consent of lenders holding at least two-thirds of the then outstanding principal amount of the convertible notes. The March 2013 Investor Notes are not secured.

In the event of an IPO, the holders of the March 2013 Arcapita Notes have the option to convert the outstanding principal into shares of the Company’s common stock at the price per share of common stock paid by purchasers in the IPO multiplied by stated discount factors set forth in the agreements ranging from a high of 75.0% on the date of issuance to a low of 49.4% at maturity. The Company may not prepay the March 2013 Arcapita Notes without the consent of the lender. The March 2013 Arcapita Notes are not secured.

In the event of a sale of the Company, the March 2013 Investor Notes would be payable in cash at the closing. The amount due upon sale of the Company would be equivalent to the outstanding principal and accrued interest divided by the applicable Conversion Percentage on the date of the sale, as defined above.

In the event of a sale of the Company, the holders of the March 2013 Arcapita Notes would have the option to (i) convert the principal value of the notes to one share of nonparticipating preferred stock, as defined, or (ii) receive the principal value of the notes in cash at the closing. The value of the share of preferred stock to be issued upon the conversion of the Arcapita Notes would be equivalent to the principal value of the notes divided by the applicable discount factors on the date of the sale, as defined above.

Pursuant to side letter agreements, in March and May 2013, holders of $7.5 million of Convertible Notes (see note 8) issued in November 2012 and January 2013 (the Initial Notes) exchanged their original principal balance for an equivalent principal amount of Senior Convertible Notes (the Exchanged Notes) and a pro-rata share of Series C warrants issued under the March 2013 NPA. The Company accounted for the warrant as a debt issuance cost and recorded an immediate charge for the fair value of the Series C warrants totaling $5.4 million in interest expense. Pursuant to the exchange, the holders of the Exchanged Notes received notes senior in preference to the Initial Notes and with an extended maturity date of March 28, 2016.

Given that the terms of the Exchanged Notes are substantially different than the terms of the Initial Notes, the exchange was accounted for as an extinguishment of debt. Upon the exchange, the Company recognized a loss totaling $5.7 million representing the difference between (i) the fair value of the Exchanged Notes at reissuance and the fair value of Series C preferred stock warrants, and (ii) the carrying value of the Initial Notes. The Company elected to account for all of the issuances of its Senior Convertible Notes and various embedded derivatives in accordance with ASC Topic 825-10, Fair Value Option for Financial Liabilities, whereby the Company initially and subsequently measured this financial instrument in its entirety at fair value, with the changes in fair value recorded each reporting period in other interest expense (income).

In March and May 2013, the Company issued an additional $15.0 million of Senior Convertible Notes. The noteholders received a pro-rata share of Series C warrants for their participation in the financing. The Company accounted for the warrant issuances as a debt issuance cost and recorded an immediate charge for the fair value of the Series C warrants totaling $10.7 million in interest expense (see note 10). In conjunction with the March 2013 NPA, the Company incurred $0.9 million of debt issuance costs, which was allocated between the debt and equity instruments related to the transaction. $0.6 million was allocated to the notes and recorded through interest expense, while the remaining $0.3 million was allocated to the warrants with an offset for additional paid-in capital.

Net proceeds from the issuance of the Senior Convertible Notes were used (i) for investment in working capital to support revenue growth (ii) for capital expenditures to improve the efficiency and throughput of existing manufacturing assets and (iii) to settle all cash obligations under the Company’s cross license agreement with Cabot Corporation (see note 11).

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Fair Value Option

At December 31, 2013, the aggregate fair value of the March 2013 Investor Notes was determined to be $24.5 million with an aggregate unpaid principal balance totaling $19.5 million. The fair value over unpaid principal was $5.0 million.

At December 31, 2013, the aggregate fair value of the March 2013 Arcapita Notes was determined to be $3.7 million, with an aggregate unpaid principal balance totaling $3.0 million. The fair value over unpaid principal was $0.7 million.

Included in interest expense for the year ended December 31, 2013 was the charge for the fair value of the Series C warrants of $10.7 million and changes in fair value of the Senior Convertible Notes of $5.6 million (see note 10).

Fair Value Measurements

The fair value of the Senior Convertible Notes was determined by utilizing a probability weighted discounted cash flow analysis which took into consideration market and general economic events as well as the Company’s financial results and other data available as of December 31, 2013. This analysis determined the amount to be paid on the notes in either cash or shares at the occurrence of certain events in which the Senior Convertible Notes would be converted into shares of the Company’s common stock or would be repaid to the noteholders in cash. The probability weighted discounted cash flow analysis utilized assumptions related to the probability of the occurrence of each of the various events and appropriate discount rates for each of the scenarios as follows:

Potential exit scenario event	Estimated exit date of future event	Estimated probability of future event
IPO scenario 1	06/30/14		45	%
IPO scenario 2	03/31/15		5	%
Sale scenario 1	06/30/14		15	%
Sale scenario 2	03/31/15		15	%
Dissolution	09/30/14		5	%
Private company	At maturity		15	%

The above scenarios incorporated a weighted average implied discount rate of 41.7%.

If the likelihood of an IPO increased by 10% and the likelihood of a sale of the Company decreased by 10%, the fair value of the Senior Convertible Notes could decrease by $0.2 million, or 0.8%. Alternatively, if the likelihood of an initial public offering decreased by 10% and the likelihood of a sale of the Company increased by 10%, the fair value of the Senior Convertible Notes could increase by $0.2 million, or 0.8%.

If there was a delay or acceleration by 30 days in the assumed timing of the IPO or sale of the Company/assets, the fair value of the Senior Convertible Notes could decrease or increase by $0.5 million, or 1.9%, respectively.

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The following table presents a roll-forward of the fair value of Level 3 (significant unobservable inputs) Senior Convertible Notes for the years ended December 31, 2012 and 2013:

	Investor Notes		Arcapita Notes		Total Senior Convertible Notes
Beginning balance as of December 31, 2012	$	—	$	—	$	—
Issuances of senior convertible notes		13,435		1,536		14,971
Fair value of notes exchanged for senior convertible notes		6,132		1,444		7,576
Change in fair value included in interest expense		4,915		673		5,588
Balance at December 31, 2013	$	24,482	$	3,653	$	28,135

(8) Convertible Notes

Convertible Notes consist of the following:

	December 31
	2012		2013
	(In thousands)
Investor Notes	$	90,920	$	87,479
Arcapita Notes	$	4,168		4,395
Total Convertible Notes	$	95,088	$	91,874
Current maturities of convertible notes		—		(435	)
Convertible Notes, excluding current portion	$	95,088	$	91,439

Commencing in June 2011 and concluding in January 2013, the Company issued a total of $69.9 million of 8% subordinated convertible notes (the Investor Notes) to new and existing investors. The Investor Notes had original maturity dates of June 1, 2014, June 14, 2014 and December 6, 2014, depending on their date of issuance. Commencing in December 2011 and concluding in September 2012, the Company issued a total of $3.5 million of noninterest bearing convertible notes to an existing investor (the Arcapita Notes). The Arcapita Notes were originally set to mature on December 6, 2014. Net proceeds from the Investor Notes and Arcapita Notes (collectively, the Convertible Notes) were used to fund the completion of the Company’s second production line at the East Providence facility, to begin the construction of a third production line at the East Providence facility, and to fund the Company’s operating cash requirements.

In conjunction with the execution of the March 2013 NPA (see note 7) on March 28, 2013, the holders of all but approximately $0.3 million of original principal amount of the Convertible Notes agreed to extend the original maturity date of their notes by two years. Given that the term of the Convertible Notes, as amended, differed substantially from the original term, the amendment was accounted for as an extinguishment of debt. On March 28, 2013, the Company recognized a gain on extinguishment totaling $8.9 million which represents the difference between (i) the fair value of the Convertible Notes at reissuance, and (ii) the fair value of the Convertible Notes just prior to the amendment.

The Investor Notes bear interest at a rate of 8% per annum compounded annually and added to principal on December 31st of each year. Accrued and unpaid interest will be payable at maturity or on the date of any prepayment. Accrued interest is payable in cash at the time of payment of principal or converted with the outstanding principal amount into common shares of the Company upon an IPO. Upon maturity, the Company will be required to pay 1.375 times the aggregate principal amount and accrued interest on the Investor Notes then outstanding. Aggregate principal amounts due on December 6, 2014, June 1, 2016 and December 6, 2016 are $0.5 million, $61.0 million and $63.5 million, respectively.

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The Arcapita Notes are non-interest-bearing and are due on December 6, 2016. The Arcapita Notes include an option to purchase one share of nonparticipating preferred stock, as defined, on the maturity date. This preferred stock will be senior to all other series of the Company’s outstanding convertible preferred stock and will have a liquidation preference totaling $6.8 million. If this option were to be exercised, the Company would create a new series of preferred stock that is currently not authorized.

In the event of an IPO, the outstanding principal and accrued interest of the Investor Notes are subject to automatic conversion into shares of the Company’s common stock at the applicable Conversion Price. The Conversion Price is defined as the price per share of common stock paid by purchasers in the IPO multiplied by the Conversion Percentage. The Conversion Percentage is defined as (i) 75.0% prior to the first anniversary of the convertible notes issuance, or 62.5% on or after the first anniversary of the convertible notes issuance for the Investor Notes issued under the June 2012 note purchase agreement, and (ii) 87.5% prior to the first anniversary of the convertible notes issuance, 75.0% on or after the first anniversary but prior to the second anniversary of the convertible notes issuance, and 62.5% on or after the second anniversary of the convertible notes issuance for the Investor Notes issued under the December 2011 note purchase agreement. The Company may not prepay the Investor Notes without the consent of lenders holding at least two-thirds of the then outstanding principal amount of the convertible notes. The Investor Notes are not secured.

In the event of an IPO, the holders of the Arcapita Notes will convert the outstanding principal into shares of the Company’s common stock at the price per share of common stock paid by purchasers in the IPO multiplied by stated discount factors set forth in the agreements ranging from a high of 87.5% on the date of issuance to a low of 49.2% on the date of maturity. The Company may not prepay the Arcapita Notes without the consent of the lender. The Arcapita Notes are not secured.

In the event of a sale of the Company, the Investor Notes would be payable in cash at the closing. The amount due upon sale of the Company would be equivalent to the outstanding principal and accrued interest divided by the applicable Conversion Percentage on the date of the sale, as defined above.

In the event of a sale of the Company, the holders of the Arcapita Notes would have the option to (i) convert the principal value of the notes to one share of nonparticipating preferred stock, as defined, or (ii) receive the principal value of the notes in cash at the closing. The value of the share of preferred stock to be issued upon the conversion of the Arcapita Notes would be equivalent to the principal value of the notes divided by the applicable discount factors on the date of the sale, as defined above.

Upon issuances, the Company elected to record the Convertible Notes at fair value which total $95.1 million and $91.9 million at December 31, 2012 and December 31, 2013, respectively.

Fair Value Option

The following table presents the difference between the aggregate fair value and the aggregate unpaid principal balance of the Convertible Notes recorded at fair value:

	Aggregate fair value December 31, 2012		Aggregate unpaid principal balance December 31, 2012		Fair value over unpaid principal balance
	(In thousands)
Investor Notes	$	90,920	$	66,411	$	24,509
Arcapita Notes		4,168		3,479		689
Total Convertible Notes	$	95,088	$	69,890	$	25,198

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	Aggregate fair value December 31, 2013		Aggregate unpaid principal balance December 31, 2013		Fair value over unpaid  principal balance
	(In thousands)
Investor Notes	$	87,479	$	68,264	$	19,215
Arcapita Notes		4,395		3,479		916
Total Convertible Notes	$	91,874	$	71,743	$	20,131

The charge recognized as a result of the change in the fair value of the Company’s Convertible Notes was $5.7 million, $19.5 million and $9.4 million for the years ended December 31, 2011, 2012 and 2013, respectively (see note 10).

Fair Value Measurements

The fair value of the Convertible Notes was determined by utilizing a probability weighted discounted cash flow analysis which took into consideration market and general economic events as well as the Company’s financial results and other data available as of December 31, 2012 and 2013. This analysis determined the amount to be paid on the notes in either cash or shares at the occurrence of certain events in which the Convertible Notes would be converted into shares of the Company’s common stock or would be repaid to the noteholders in cash. The probability weighted discounted cash flow analysis utilized assumptions related to the probability of the occurrence of each of the various events and appropriate discount rates for each of the scenarios as follows:

	December 31, 2012					December 31, 2013
Potential exit scenario event	Estimated exit date of future event		Estimated probability of future event			Estimated exit date of future event		Estimated probability of future event
IPO scenario 1		06/30/14		10	%		06/30/14		45	%
IPO scenario 2		03/31/15		5	%		03/31/15		5	%
Sale scenario 1		06/30/13		60	%		06/30/14		15	%
Sale scenario 2		06/30/14		10	%		03/31/15		15	%
Dissolution		06/30/13		5	%		09/30/14		5	%
Private company		At maturity		10	%		At maturity		15	%

The above scenarios incorporated weighted average implied discount rates of 31% and 40% at December 31, 2012 and 2013, respectively.

As of December 31, 2013, if the likelihood of an IPO increased by 10% and the likelihood of a sale of the Company decreased by 10%, the fair value of the Convertible Notes could decrease by $0.7 million, or 0.8%. Alternatively, if the likelihood of an IPO decreased by 10% and the likelihood of a sale of the Company increased by 10%, the fair value of the Convertible Notes could increase by $0.7 million, or 0.8%.

As of December 31, 2013, if there was a delay or acceleration by 30 days in the assumed timing of the IPO or sale of the Company/assets, the fair value of the Convertible Notes could decrease or increase by $1.6 million, or 1.9%, respectively.

Given that the valuation of the Convertible Notes utilized several unobservable inputs, the Company determined that the valuation of the Convertible Notes is a Level 3 valuation.

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The following table presents a roll-forward of the fair value of Level 3 (significant unobservable inputs) Convertible Notes for the years ended December 31, 2011, 2012 and 2013:

	Investor Notes			Arcapita Notes			Total Convertible Notes
Balance at December 31, 2011		50,118			585			50,703
Issuances of convertible notes		21,991			2,900			24,891
Change in fair value included in interest expense		18,811			683			19,494
Balance at December 31, 2012		90,920			4,168			95,088
Issuances of convertible notes		2,090			1,440			3,530
Fair value of notes exchanged for senior convertible notes		(5,971	)		(1,282	)		(7,253	)
Gain on extinguishment of convertible notes		(8,498	)		(400	)		(8,898	)
Change in fair value included in interest expense		8,938			469			9,407
Balance at December 31, 2013	$	87,479		$	4,395		$	91,874

(9) Revolving Line of Credit

In March 2011, the Company entered into a two-year, $10.0 million revolving line of credit facility with a bank under which the Company can borrow up to $8.6 million due to a borrowing limitation under the terms of the credit facility of $1.4 million. Borrowings under the line of credit accrue interest at the greater of the prime rate or 4% per annum (4% as of December 31, 2012 and 2013) plus 1.0% per annum. The facility also includes fees based on unused portions of the line of credit, among others. The line of credit is secured by a second priority security interest in fixed assets at the East Providence facility and a first priority security interest in all other assets of the Company, including all intellectual property.

On June 28, 2013, the Company renewed its line of credit agreement, extended the maturity date of the facility to June 27, 2014 and increased its available borrowing base. On March 31, 2014, the Company amended its line of credit agreement which extended the maturity date of the facility to July 27, 2014 (see note 20).

At December 31, 2012 and 2013, the Company had drawn $1.3 million and $1.0 million, respectively, on the line of credit. The Company had outstanding letters of credit of $1.7 million and $1.2 million at December 31, 2012 and 2013, respectively. The remaining amount available to the Company under the line of credit at December 31, 2013 was $6.4 million.

Under the line of credit, the Company is required to comply with financial covenants relating to free cash flow and liquidity. As of December 31, 2013, the Company was in compliance with all such financial covenants.

F-25

(10) Interest Expense

Interest expense consists of the following:

	Year ended December 31
	2011		2012		2013
Changes in fair value:
Subordinated notes(2)	$	—	$	1,100	$	3,771
Senior convertible notes		—		—		5,588
Convertible notes, net of capitalization(1)		4,752		17,578		9,337
Issuance of Series C preferred stock warrants in connection with senior convertible notes		—		—		10,677
Subordinated notes interest, net of capitalization(2)		554		822		—
Amortization of deferred financing costs for subordinated notes		624		636		—
Debt closing costs		623		425		585
Loan application fees		564		—		—
Imputed interest on Cabot obligation		1,665		1,018		391
Other interest		40		211		250
	$	8,822	$	21,790	$	30,599

(1) The charge recognized as a result of the change in the fair value of the Company’s Convertible Notes is presented net of capitalized interest expense of $1.0 million, $1.9 million and $0.1 million for the years ended December 31, 2011, 2012 and 2013, respectively.

(2) Interest expense recognized from the Company’s Subordinated Notes is presented net of capitalized interest expense of $0.7 million, $0.3 million and $0.0 million for the years ended December 31, 2011, 2012 and 2013, respectively.

Debt closing costs, consisting primarily of legal and related fees, associated with the issuance or modification of the Company’s Subordinated Notes, Senior Convertible Notes and Convertible Notes are recorded in interest expense as incurred.

In September 2011, the Company expensed previously deferred financing costs associated with the pursuit of a certain loan guarantee with the U.S. Department of Energy.

Capitalized interest relates primarily to costs associated with the Company’s second and third production lines at the East Providence facility.

(11) Other Long-term Liabilities

Other long-term liabilities consist of the following:

	December 31
	2012			2013
	(In thousands)
Asset retirement obligations (ARO)	$	1,000		$	1,009
Cross license agreement		5,608			—
Patent amortization		163			112
		6,771			1,121
Current maturities of other long-term liabilities		(6,771	)		—
Other long-term liabilities, less current maturities	$	—		$	1,121

The Company has asset retirement obligations (ARO) arising from requirements to perform certain asset retirement activities upon the termination of its Northborough, Massachusetts facility lease and upon disposal of

F-26

certain machinery and equipment. The liability was initially measured at fair value and subsequently is adjusted for accretion expense and changes in the amount or timing of the estimated cash flows. The corresponding asset retirement costs are capitalized as part of the carrying amount of the related long-lived asset and depreciated over the asset’s remaining useful life.

A summary of ARO activity consists of the following:

	Year Ended December 31
	2012			2013
	(In thousands)
Balance at beginning of period	$	971		$	1,000
Accretion of discount expense		31			34
Settlement costs		(2	)		(25	)
Balance at end of period	$	1,000		$	1,009

In August 2013, the Company extended its Northborough, Massachusetts facility lease. As a result, the Company classified the ARO as long term at December 31, 2013.

On April 1, 2006, the Company and Cabot Corporation entered into a Cross License Agreement to license certain intellectual property rights. Such licenses will expire on the last day of the life of each issued patent or patent applications and acquired patents licensed thereunder. On September 21, 2007, the Cross License Agreement was amended to modify the consideration payable to Cabot by the Company to $38.0 million in cash in quarterly installments over a seven-year period. The Company adjusted its obligation to Cabot to reflect a revised net present value of the consideration payable to Cabot of $19.3 million. The discount of $18.7 million was amortized to interest expense over the term of the payment schedule.

The consideration provided to Cabot was for the value of the licensed patents and patent applications, the avoidance of potential claims on prior use of Cabot issued patents and related costs. $1.0 million of the total consideration was allocated to the fair market value of the patents and patent applications licensed from Cabot, $0.5 million was allocated to the fair market value of the patents and patent applications licensed to Cabot, and the remainder was allocated to general and administrative expenses.

The remaining consideration payable to Cabot under the Cross License Agreement was paid in full during 2013.

F-27

(12) Commitments and Contingencies

Capital Leases

The Company has entered into certain capital leases for computer equipment and vehicles. The leases are payable in monthly installments and expire at various dates through 2017. The recorded balance of capital lease obligations as of December 31, 2012 and 2013 was $0.1 million and $0.2 million, respectively. Future minimum payments under capital leases at December 31, 2013 are as follows:

Year	Capital  Lease Obligations
	(In thousands)
2014	$	97
2015		87
2016		64
2017		30
Total		278
Less portion representing interest		(38	)
Present value of future minimum payments		240
Current maturities of capital lease payments		(75	)
Capital leases, excluding current portion	$	165

Operating Leases

The Company leases facilities and office equipment under operating leases expiring at various dates through 2021. Under these agreements, the Company is obligated to pay annual rentals, as noted below, plus real estate taxes, and certain operating expenses. Some operating leases contain rent escalation clauses whereby the rent payments increase over the term of the lease. In such cases, rent expense is recognized on a straight-line basis over the lease term.

Future minimum lease payments under operating leases at December 31, 2013 are as follows:

Year	Operating Leases
	(In thousands)
2014	$	934
2015		969
2016		829
2017		24
2018		25
Thereafter		61
Total minimum lease payments	$	2,842

The Company incurred rent expense under all operating leases of approximately $0.9 million, $1.2 million and $1.2 million for the years ended December 31, 2011, 2012 and 2013, respectively.

Letters of Credit

Pursuant to the terms of its Northborough, Massachusetts facility lease, the Company has been required to provide the lessor with letters of credit securing certain obligations. In addition, the Company has been required to provide certain customers with letters of credit securing obligations under commercial contracts.

The Company had letters of credit outstanding for $1.7 million and $1.2 million at December 31, 2012 and 2013, respectively. These letters of credit are secured by the Company’s revolving line of credit (see note 9).

F-28

Litigation

The Company is, from time to time, a party to litigation that arises in the normal course of its business operations. The Company is not presently a party to any litigation for which it believes a loss is probable requiring an amount to be accrued or a possible loss contingency requiring disclosure.

(13) Redeemable Convertible Preferred Stock

In August and September 2009, the Company issued 5,284,347 shares of Series A Redeemable Convertible Preferred Stock (Series A) to a group of new and existing investors at a price of $5.83602175 per share, for net proceeds of approximately $30.5 million.

In September and October 2010, the Company issued 1,601,053 shares of Series B Redeemable Convertible Preferred Stock (Series B) to a group of new and existing investors at a price of $13.36802380 per share, for net proceeds of $21.1 million.

Holders of a majority of the Company’s Series B and Series A, voting together as a single class, had the right to require the Company to redeem in three annual installments all the then outstanding shares of Series B and Series A at a redemption price equal to the sum of (i) the greater of the applicable liquidation amount or fair market value of the shares and (ii) accrued but unpaid dividends. As a result of this right, the Series B and Series A preferred stock was measured based on the greater of fair value or liquidation value on a recurring basis. During the year ended December 31, 2012, the Company recorded decreases in the redemption value of the Company’s Series B and Series A shares of $5.5 million and $45.9 million, respectively, reflecting the changes in the fair market value of the Series B and of the Series A shares at December 31, 2012.

The fair value of the Company’s redeemable convertible preferred stock was estimated using the probability-weighted expected return method, or PWERM, which considers the value of preferred and common stock based upon analysis of the future values for equity assuming various future outcomes, including initial public offerings, merger or sale, dissolutions or continued operation as a private company. Accordingly, share value is based upon the probability-weighted present value of expected future net cash flows, considering each of the possible future events, as well as the rights and preferences of each share class. As such, the Company’s redeemable convertible preferred stock was valued utilizing Level 3 inputs.

On December 31, 2012, the Company’s board of directors established the price per share of the Company’s Series B and Series A shares at $16.30 and $9.10 per share, respectively, as determined by the PWERM method. This valuation took into consideration market and general economic events as well as the Company’s financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples based on comparable companies was appropriate. At December 31, 2012, the various scenarios, excluding dissolution, resulted in equity fair values ranging from $120.0 million to $245.0 million. At December 31, 2012, the valuations were weighted as follows: IPO, 15%; sale of the Company/assets, 70%; remain private, 10%; and dissolution, 5%. The estimated fair value of one share of common and preferred stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability weighted value per share.

In conjunction with the execution of the March 2013 NPA, the redemption and dividend rights of the Company’s issued and outstanding Series B and Series A were eliminated and the liquidation preference of the Series B and Series A was reduced to an aggregate of $4.0 million. During March 2013, the Company recorded decreases in the redemption value of the Company’s Series B and Series A shares of $30.0 million and $56.1 million, respectively, reflecting the changes in the fair market value of the Series B and Series A shares at the time of the March 2013 Financing. Given that the release of the redemption rights substantially impacts the fair value of the Series B and Series A, the elimination of the rights was accounted for as an extinguishment of the securities. As a result, the Company recorded a gain on extinguishment of Series B and Series A of approximately $86.2 million recorded in additional paid-in capital available to common stockholders.

F-29

Additionally, the remaining value of the Series B and Series A of $1.1 million subsequent to extinguishment was recorded in additional paid-in capital upon reclassification from temporary to permanent equity.

At the time of the March 2013 Financing, the Company’s board of directors established the price per share of the Company’s Series B and Series A shares at $0.20 and $0.15 per share, respectively, as determined by the PWERM method. This valuation took into consideration market and general economic events as well as the Company’s financial results and other data available at that time. In addition, the board reaffirmed that the continued use of market multiples based on comparable companies was appropriate. At the time of the March 2013 Financing, the various scenarios, excluding dissolution, resulted in equity fair values ranging from $20.0 million to $215.0 million. At the time of the March 2013 Financing, the valuations were weighted as follows: IPO, 40%; sale of the Company/assets, 45%; dissolution, 10%; and remain private, 5%. The estimated fair value of one share of common and preferred stock was estimated under each of the four scenarios and the associated probabilities to arrive at a probability weighted value per share.

The following is a summary of the Company’s redeemable convertible preferred stock:

	Series B						Series A
	Shares			Amount			Shares			Amount
	(In thousands, except share amounts)
Balance at December 31, 2010		1,601,053			28,799			5,284,347			80,987
Dividends		—			1,714			—			2,468
Changes in redemption value		—			3,194			—			16,289
Balance at December 31, 2011		1,601,053			33,707			5,284,347			99,744
Dividends		—			1,717			—			2,474
Changes in redemption value		—			(5,489	)		—			(45,903	)
Balance at December 31, 2012		1,601,053			29,935			5,284,347			56,315
Dividends		—			408			—			588
Changes in redemption value at extinguishment		—			(30,030	)		—			(56,131	)
Reclassification from temporary to permanent equity		(1,601,053	)		(313	)		(5,284,347	)		(772	)
Balance at December 31, 2013		—		$	—			—		$	—

(14) Stockholders’ (Deficit) Equity

Authorized Shares

At December 31, 2013, the Company was authorized to issue 333,797,872 shares of stock, of which 210,888,230 shares were designated as common stock, 5,284,347 shares were designated as Series A Preferred Stock, 1,601,053 shares were designated as Series B Preferred Stock and 116,024,242 shares were designated as Series C Preferred Stock (collectively, the Preferred Stock).

Common Stock Warrants

Warrants to purchase 112,576 shares of the Company’s common stock were outstanding at December 31, 2013 with a weighted average exercise price of $0.017 per share.

Preferred Stock Warrants

In conjunction with the issuance of the Senior Convertible Notes during March and May 2013 (see note 7), the Company issued warrants to purchase 87,018,187 shares of Series C Preferred Stock. The Series C warrants are subject to adjustment for any dividends or distributions on exercise and shall receive such dividends or distributions to which the holder would have been entitled if the holder had exercised the warrant at the time of adjustment without the payment of additional consideration. Warrants to purchase 86,998,187 shares of Series C were outstanding at December 31, 2013.

F-30

Convertible Preferred Stock

In conjunction with the execution of the March 2013 NPA, the redemption and dividend rights of the Company’s issued and outstanding Series B and Series A were eliminated and the liquidation preference of the Series B and A was reduced to an aggregate of $4.0 million. Given that the release of the redemption rights substantially impacted the fair value of the Series B and Series A, the elimination of the rights were accounted for as an extinguishment of the securities. In addition, the Company authorized issuance of the newly created Series C.

As described in the Company’s certificate of incorporation, the rights and preferences of the Series C, Series B and Series A are as follows:

(a) Voting Rights

Holders of Series C, Series B and Series A shares are entitled to vote on all matters as to which holders of common stock are entitled to vote, and with a number of votes equal to the number of shares of common stock into which each share of preferred stock is then convertible.

(b) Dividends

Holders of Series C, Series B and Series A shares are not entitled to receive any dividends unless dividends are declared on the common stock.

(c) Liquidation Rights

In the event of any liquidation, dissolution or winding-up of the Company, and before any distribution payments are to be made to the holders of the Series B, Series A or common stock, holders of the Series C are entitled to receive an aggregate liquidation amount of $30.0 million. In addition, before any distribution payments are to be made to the holders of common stock, holders of the Series B and the Series A are entitled to receive an aggregate liquidation amount of $4.0 million.

(d) Participation

Holders of the Series C, Series B and Series A have the right to participate in distribution payments to the holders of common stock on an as-converted basis.

(e) Conversion

Each holder of Series C, Series B and Series A has the right to convert such shares into common stock at any time based on a defined conversion ratio. In addition, each share of Preferred Stock will convert to common stock automatically upon (i) the affirmative vote of the majority of the Series C, (ii) upon completion of the first underwritten public offering of common stock with aggregate proceeds of at least $60 million, or (iii) upon completion of the first underwritten public offering of common stock in which the holders of a majority of the Senior Convertible Notes elect to convert such notes into common stock.

The aggregate amount of common stock issuable upon conversion in full of authorized preferred shares is 125,339,831 shares, composed of (i) 116,024,242 shares of common stock upon conversion of Series C, (ii) 2,396,045 shares of common stock upon conversion of Series B, and (iii) 6,919,544 shares of common stock upon conversion of Series A.

The defined conversion ratio is subject to adjustment (i) if the number of shares of common stock outstanding is increased by a stock dividend or stock split, or is decreased by a stock combination; or (ii) in the event of any capital reorganization, any reclassification of the stock (other than a change in par value) or any consolidation or merger.

(f) Redemption

As part the March 2013 financing, the redemption rights of Series B and Series A were eliminated (see note 13). At December 31, 2013, the Series C, Series B and Series A are non-redeemable.

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(15) Employee Benefit Plan

The Company sponsors the Aspen Aerogels, Inc. 401(k) Plan. Under the terms of the plan, the Company’s employees may contribute a percentage of their pretax earnings. The Company has not provided matching contributions nor has it made any contributions to the plan.

(16) Employee Stock Options

The Company maintains the 2001 Equity Incentive Plan, as amended (the Plan), pursuant to which the Company’s Board of Directors may grant qualified and nonqualified common stock options to officers, key employees and others who provide or have provided service to the Company. Under the terms of the Plan, stock options are granted with an exercise price not less than the contemporaneous fair market value of the Company’s common stock at the date of grant.

During the years ended December 31, 2011, 2012 and 2013, the Company issued stock options with a 10-year term that contain service conditions. Generally, these stock options vest and become exercisable over a service period of three to four years from the date of grant.

During the year ended December 31, 2013, the Company also issued stock options with a 10-year term that contain both a performance condition and a service condition. The performance-based options shall vest and become exercisable only in the event of the completion of the Company’s IPO and then over a service period of three to four years from the date of grant. The number of shares subject to the performance-based options shall be reduced, if necessary, such that each holder’s total option holdings shall equal a target percentage of the Company’s common stock deemed outstanding immediately prior to the IPO. The aggregate target percentage for all holders of performance-based options issued during the year ended December 31, 2013 was 15.384%. If the number of shares subject to these options is insufficient to achieve the target percentage in an IPO, the Company is under no obligation to grant additional options to the holder.

At December 31, 2013, the Plan reserved 82,828,526 shares of common stock for future grant of stock options. At December 31, 2013, there were 2,614,127 shares available for grant under the Plan.

Valuation and Amortization Method

Given that the Company does not maintain an external market for its shares, the Board of Directors has historically determined the fair value of the Company’s common stock based on the market approach and the income approach to estimate the enterprise value of the business under various liquidity event scenarios, including an IPO by the Company and the sale of the Company. To support the valuations, the Company utilized a probability-weighted expected return under those various liquidity scenarios, public guideline companies, management cash flow projections and other assumptions to derive the enterprise value of the business. The Company then derived the estimated fair value of each class of stock, taking into consideration the rights and preferences of each instrument based on a probability-weighted expected return.

The fair value of each stock option was estimated as of the date of grant using the Black-Scholes option pricing model. Key inputs into this formula included expected term, expected volatility, expected dividend yield and the risk-free rate. Each assumption is set forth and discussed below.

For the performance-based stock options issued during the year ended December 31, 2013, the Company used a Monte Carlo simulation model to estimate the number of options expected to remain outstanding and eligible for vesting upon completion of the Company’s IPO. The simulation model is based on a number of complex assumptions including the terms of the performance condition, the value of our common stock at the time of the Company’s IPO, the expected time from the date of grant to the Company’s IPO and expected volatility. The number of options expected to remain outstanding and eligible for vesting upon completion of the

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Company’s IPO was estimated to be 96.8% and 97.4% of the options granted at August 7, 2013 and December 20, 2013, respectively. The fair value of each performance-based stock option was determined by multiplying the Black-Scholes estimate of grant date fair value by the percentage of options expected to remain outstanding and eligible for vesting upon completion of the Company’s IPO.

For stock options with a service condition, the fair value is amortized on a straight-line basis over the requisite service period of the options, which is generally a three- to four-year vesting period from the date of grant. For the performance-based stock options issued during the year ended December 31, 2013, a portion of the fair value will be recognized as expense when the IPO performance condition is probable of being achieved and the remainder over the requisite service period, which is generally a three- to four-year vesting period from the date of grant.

Expected Term

The expected term represents the period that the Company’s stock-based awards are expected to be outstanding. The Company uses the simplified method as prescribed by FASB ASC 718 to calculate the expected term for options granted, as it does not have sufficient historical exercise data to provide a reasonable basis upon which to estimate the expected term.

Expected Volatility

Due to the Company’s limited historical data, the estimated volatility reflects the incorporation of the historical volatility of comparable companies with publicly available share prices. In 2011, 2012 and 2013, the expected volatility is based on the weighted average volatility of up to six companies within various industries that the Company believes are similar to its own.

Expected Dividend

The Company uses an expected dividend yield of zero. The Company does not intend to pay cash dividends on its common stock in the foreseeable future, nor has it paid dividends on its common stock in the past.

Risk-free Interest Rate

The risk-free interest rate is based on U.S. Treasury zero-coupon issues with a remaining term equal to the expected life assumed at the date of grant.

Estimated Forfeitures

Forfeitures are required to be estimated at the time of grant and revised, if necessary, in subsequent periods, if actual forfeitures differ from those estimates. Forfeitures were estimated based on voluntary termination behavior as well as analysis of actual option forfeitures. Accordingly, share-based compensation expense has been reduced by an estimated forfeiture rate of 3% for 2011, 2012 and 2013.

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Assumptions Utilized

The following information relates to the fair value of the option awards estimated by use of the Black-Scholes option pricing model:

	Year Ended December 31
	2011			2012			2013
Weighted average assumptions:
Expected term (in years)		6.05			6.02			5.47
Expected volatility		49.33	%		58.06	%		48.99	%
Risk free rate		2.06	%		0.95	%		1.69	%
Expected dividend yield		0.00	%		0.00	%		0.00	%
Weighted average fair value:
Grant-date fair value of options granted	$	10.30		$	5.60		$	0.12
Grant-date fair value of options vested	$	1.70		$	2.30		$	0.18
Aggregate intrinsic value of options exercised	$	252		$	—		$	—

Modifications

On August 7, 2013, the Company canceled substantially all options held by Company employees under the 2001 equity incentive plan and granted two sets of new options to these employees. Each recipient received a grant of options containing service-based vesting conditions and a second grant of options containing both service and performance-based vesting conditions. The performance-based vesting is met upon the successful completion of an IPO of the Company’s common stock.

On December 20, 2013, the Company canceled all options held by members of the Company’s board of directors under the 2001 equity incentive plan and granted two sets of new options to these directors. Each recipient received a grant of options containing service-based vesting conditions and a second grant of options containing both service and performance-based vesting conditions. The performance-based vesting is met upon the successful completion of an IPO of the Company’s common stock.

As a result of the cancellation and concurrent grant of options, the Company accounted for these transactions as modifications in determining the stock-based compensation expense to be recognized over the remaining service period. The total incremental compensation expense resulting from the modification was $7.8 million and $1.0 million for the two grant dates, respectively. The incremental compensation expense associated with the service-based awards of $2.0 million will be recognized over the remaining service period of the new options. The Company has yet to record any compensation expense of the remainder of $6.1 million associated with the performance-based awards, because the performance condition cannot be considered probable until it occurs.

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Outstanding Options

The following table summarizes information about stock options outstanding:

	Number of Shares			Weighted Average Grant Date Fair Value Per Share		Weighted Average Exercise Price Per Share		Weighted Average Remaining Contractual Term (Years)		Aggregate Intrisic Value
	($ in thousands, except share and per share data)
Options outstanding at December 31, 2012		2,267,438		$	4.14	$	7.98		8.18	$	3,143
Granted		80,225,527		$	0.12	$	0.10
Forfeited		(2,294,425	)	$	3.88	$	7.42
Exercised		—		$	—	$	—			$	—
Options outstanding at December 31, 2013		80,198,540		$	0.12	$	0.11		9.63	$	14,589
Exercisable at December 31, 2013		8,436,457		$	0.18	$	0.23		9.51	$	1,606
Expected to vest at December 31, 2013		71,544,579		$	0.12	$	0.10		9.64	$	12,961

As of December 31, 2013, there was $10.8 million of total unrecognized compensation cost related to nonvested options granted under the Plan. The unrecognized compensation cost consisted of $3.5 million relating to service-based awards and $7.3 million for performance-based awards. The unrecognized compensation cost for the service-based options is expected to be recognized over a weighted average period of 2.65 years. Recognition of the compensation cost of the performance-based options will occur at the time the performance condition is met and, thereafter, over the requisite service period.

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(17) Net Income (Loss) Per Share

The computation of basic and diluted net income (loss) per share attributable to common stockholders consists of the following:

	Year ended December 31
	2011			2012			2013
	(In thousands, except share and per share data)
Numerator:
Net income (loss)	$	(32,832	)	$	(56,142	)	$	(47,611	)
Deemed dividends on participating preferred stock (inclusive of issuance costs and changes in redemption value, including extinguishment):
Series B		(4,908	)		3,772			29,622
Series A		(18,757	)		43,429			55,543
Total preferred stock deemed dividends		(23,665	)		47,201			85,165
Earnings attributable to participating convertible preferred stock shareholders and Series C preferred stock warrant holders		—			—			(36,216	)
Net income (loss) attributable to common stockholders	$	(56,497	)	$	(8,941	)	$	1,338
Denominator:
Weighted average shares outstanding, basic		2,607,888			2,622,897			2,623,156
Effect of warrants to purchase common stock		—			—			99,791
Weighted average shares outstanding, diluted		2,607,888			2,622,897			2,722,947
Net income (loss) attributable to common stockholders per common share, basic	$	(21.66	)	$	(3.41	)	$	0.51
Effect of warrants to purchase common stock		—			—			(0.02	)
Net income (loss) attributable to common stockholders per common share, diluted	$	(21.66	)	$	(3.41	)	$	0.49

Potential dilutive common shares that were excluded from the computation of diluted net income (loss) attributable to common stockholders per common share because they were anti-dilutive consist of the following:

	Year ended December 31
	2011		2012		2013
Series B		1,601,053		1,601,053		—
Series A		5,284,347		5,284,347		—
Common stock options		1,430,027		2,267,438		18,017,626
Common stock warrants		112,598		112,598		—
Total		8,428,025		9,265,436		18,017,626

In addition to the potentially dilutive securities noted above, as of December 31, 2011 and 2012 the Company had $50.7 million and $95.1 million of outstanding Convertible Notes, respectively, which are convertible into common stock upon the occurrence of an IPO at prices that are not determinable until the occurrence of those future events (see note 8). As of December 31, 2013 the Company had outstanding $28.1 million of Senior Convertible Notes and $91.9 million of Convertible Notes, which are convertible into common stock upon the occurrence of an IPO at prices that are not determinable until the occurrence of those future events (see notes 7 and 8), and 62,180,914 outstanding common stock options, which are exercisable into common stock upon the occurrence of an IPO and the performance of service during the vesting period (see note 16). Because the necessary conditions for the conversion of these convertible notes and common stock options had not been satisfied during the respective

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years ended, the Company has excluded these convertible notes and performance options from the table above and the calculation of diluted net (loss) income per share for the respective years ended.

(18) Income Taxes

The Company incurred net operating losses and recorded a full valuation allowance against net deferred assets for all periods presented. Accordingly, the Company has not recorded a provision for federal or state income taxes.

The reconciliation between the U.S. statutory income tax rate and the Company’s effective rate consists of the following:

	Year Ended December 31
	2011		2012		2013
U.S. federal income tax statutory rate		35%		35%		35%
Debt and warrant fair value adjustments		(6%)		(12%)		(16%)
Changes in valuation allowance for deferred tax assets		(28%)		(22%)		6%
Write down of losses not previously benefitted		0%		0%		(22%)
Other		(1%)		(1%)		(3%)
Effective tax rate		—		—		—

The tax effects of temporary differences between financial statement and tax accounting that gave rise to significant portions of the Company’s deferred tax assets and deferred tax liabilities at December 31, 2012 and 2013 are presented below:

	December 31
	2012			2013
	(In thousands)
Deferred tax assets:
Net operating loss carryforwards	$	69,219		$	67,503
Transaction related costs		1,349			1,494
Stock-based compensation		1,343			2,460
Tax credit carryforwards		400			393
Reserves and accruals		2,053			896
Other		248			127
Total gross deferred tax assets		74,612			72,873
Deferred tax liabilities:
Depreciation	$	(1,744	)	$	(2,717	)
Total deferred tax liabilities		(1,744	)		(2,717	)
Total deferred tax assets and liabilities		72,868			70,156
Valuation allowance		(72,868	)		(70,156	)
Net deferred tax asset	$	—		$	—

The net change in the valuation allowance for the year ended December 31, 2013, was a decrease of $2.7 million. The Company has recorded a full valuation allowance against its deferred tax assets due to the uncertainty associated with the utilization of the net operating loss carryforwards and other future deductible items. In assessing the realizability of deferred tax assets, the Company considers all available evidence, historical and prospective, with greater weight given to historical evidence, in determining whether it is more

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likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of the Company’s deferred tax assets generally is dependent upon generation of future taxable income.

At December 31, 2013, the Company has $173.3 million of net operating losses available to offset future federal income, if any, and which expire on various dates through December 31, 2033.

For the year ended December 31, 2010, the Company performed an analysis pursuant to Internal Revenue Code Section 382, as well as similar state provisions, in order to determine whether any limitations might exist on the utilization of net operating losses and other tax attributes. Based on this analysis, the Company has determined that it is more likely than not that an ownership change occurred on June 10, 2008, resulting in an annual limitation on the use of its net operating losses and other tax attributes as of such date. The Company also determined that built-in gains of $29.5 million existed at the date of the ownership change. Built-in gains increase the limitation under the Internal Revenue Code Section 382 to the extent triggered during the five year period subsequent to the date of change, which period ended in June 2013. As a result, the entire $29.5 million of net operating losses expired unutilized in June 2013.

For the year ended December 31, 2013, the Company performed an analysis pursuant to Internal Revenue Code Section 382, as well as similar state provisions, in order to determine whether any limitations might exist on the utilization of net operating losses and other tax attributes. Based on this analysis, the Company has determined that no ownership changes occurred as a result of the March 2013 financing (see note 7) and, as a result, there was no annual limitation on the use of its net operating losses and other tax attributes as of such date.

At December 31, 2013, the Company had $120.7 million of apportioned net operating losses available to offset future state taxable income, if any, and which begin to expire at various dates between 2014 and 2033.

For each of the years ended December 31, 2011, 2012 and 2013, the Company did not have any material unrecognized tax benefits and thus no interest and penalties related to unrecognized tax benefits were recorded. In addition, the Company does not expect that the amount of unrecognized tax benefits will change significantly within the next twelve months.

The Company files a federal income tax return in the United States and in various state and foreign jurisdictions. All tax years are open for examination by the taxing authorities for both federal and state purposes.

(19) Related Party Transactions

The Company had the following transactions with related parties:

The Company sold aerogel products to three stockholders of the Company totaling $5.1 million and $7.4 million during the years ended December 31, 2011 and 2012, respectively and two stockholders of the Company totaling $5.5 million in 2013. The Company had trade receivables with these stockholders of $1.1 million and $1.2 million at December 31, 2012 and 2013, respectively.

The Company sold aerogel products to one debt holder of the Company totaling $3.3 million and $3.5 million during the years ended December 31, 2012 and 2013, respectively. The Company had trade receivables outstanding with this debt holder of $1.1 million and $0.8 million at December 31, 2012 and 2013, respectively.

An affiliate of one of the Company’s principal stockholders is a director of a company that owns an insurance broker through which the Company purchases insurance. The Company’s yearly premiums for a

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comprehensive property and casualty insurance program were $0.5 million, $0.7 million and $0.6 million for the years ended December 31, 2011, 2012 and 2013, respectively.

In connection with note and warrant financing transactions and amendments, the Company reimbursed stockholders and noteholders $0.1 million, $0.0 million and $0.3 million during the years ended December 31, 2011, 2012 and 2013, respectively.

The Company has Senior Convertible Notes and Convertible Notes outstanding with several stockholders of the Company (see notes 6 and 7).

(20) Subsequent Events

The Company has evaluated subsequent events through March 25, 2014, the date the consolidated financial statements were originally issued, and has evaluated for disclosures and additional subsequent events occurring after such date through April 28, 2014, which is the date these consolidated financial statements were available for reissuance.

On March 31, 2014, the Company amended its revolving line of credit agreement (see note 9) to extend the maturity date of the facility to July 27, 2014 and amend the financial covenant relating to free cash flow.

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APPENDIX A — GLOSSARY OF SELECTED TERMS

The following are abbreviations and definitions of certain terms used in this document, which are commonly used in the energy industry:

“Bbl.” One stock tank barrel of 42 U.S. gallons liquid volume used herein in reference to crude oil, condensate or natural gas liquids.

“Bbl/d.” One Bbl per day.

“Bcf.” One billion cubic feet of natural gas.

“Bcf/d.” One Bcf per day.

“Btu.” One British thermal unit, the quantity of heat required to raise the temperature of a one-pound mass of water by one degree of Fahrenheit.

“CUI.” Corrosion under insulation.

“kWh.” Kilowatt hour.

“LNG.” Liquefied natural gas.

“MMBbl.” One million barrels of crude oil, condensate or natural gas liquids.

“MMBbl/d.” One MMBbl per day.

“MMft².” Millions of square feet.

“MMtpa.” One million tonnes per annum.

“MW.” Megawatt.

“Tonne.” One metric ton. A metric system unit equivalent to approximately 2,205 pounds.

“tpa.” Tonnes per annum.

A-1

             Shares

Aspen Aerogels, Inc.

Common Stock

Prospectus

                    , 2014

Barclays

J.P. Morgan

Citigroup

Through and including                     , 2014 (the 25^th day after the date of this prospectus), all dealers effecting transactions in these securities, whether or not participating in this offering, may be required to deliver a prospectus. This is in addition to a dealers’ obligation to deliver a prospectus when acting as an underwriter and with respect to an unsold allotment or subscription.

PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 13. Other Expenses of Issuance and Distribution.

The following table indicates the expenses to be incurred in connection with the offering described in this registration statement, other than underwriting discounts and commissions, all of which will be paid by us. All of the amounts are estimated except the SEC registration fee, the FINRA filing fee and the NYSE listing fee.

	Amount to be paid
SEC registration fee	$	11,109
NYSE listing fee		*
FINRA filing fee		13,438
Printing and mailing		*
Legal fees and expenses		*
Accounting fees and expenses		*
Blue sky fees and expenses		*
Transfer agent and registrar		*
Miscellaneous		*
Total	$	*

* To be provided by amendment.

Item 14. Indemnification of Directors and Officers.

Our restated certificate of incorporation and restated by-laws that will be effective upon completion of the offering provide that each person who was or is made a party or is threatened to be made a party to or is otherwise involved (including, without limitation, as a witness) in any action, suit or proceeding, whether civil, criminal, administrative or investigative, by reason of the fact that he or she is or was one of our directors or officers or is or was serving at our request as a director, officer or trustee of another corporation, or of a partnership, joint venture, trust or other enterprise, including service with respect to an employee benefit plan, whether the basis of such proceeding is alleged action in an official capacity as a director, officer or trustee or in any other capacity while serving as a director, officer or trustee, shall be indemnified and held harmless by us to the fullest extent authorized by the Delaware General Corporation Law against all expense, liability and loss (including attorneys’ fees, judgments, fines, ERISA excise taxes or penalties and amounts paid in settlement) reasonably incurred or suffered by such.

Section 145 of the Delaware General Corporation Law permits a corporation to indemnify any director or officer of the corporation against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred in connection with any action, suit or proceeding brought by reason of the fact that such person is or was a director or officer of the corporation, if such person acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, and, with respect to any criminal action or proceeding, if he or she had no reasonable cause to believe his or her conduct was unlawful. In a derivative action (i.e., one brought by or on behalf of the corporation), indemnification may be provided only for expenses actually and reasonably incurred by any director or officer in connection with the defense or settlement of such an action or suit if such person acted in good faith and in a manner that he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, except that no indemnification shall be provided if such person shall have been adjudged to be liable to the corporation, unless and only to the extent that the Delaware Chancery Court or the court in which the action or suit was brought shall determine that such person is fairly and reasonably entitled to indemnity for such expenses despite such adjudication of liability.

II-1

Pursuant to Section 102(b)(7) of the Delaware General Corporation Law, Article VI of our restated certificate of incorporation eliminates the liability of a director to us or our stockholders for monetary damages for such a breach of fiduciary duty as a director, except for liabilities arising:

• from any breach of the director’s duty of loyalty to us or our stockholders;

• from acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law;

• under Section 174 of the Delaware General Corporation Law; and

• from any transaction from which the director derived an improper personal benefit.

We have entered into indemnification agreements with our non-employee directors and will enter into similar agreements with certain officers, in addition to the indemnification provided for in our restated certificate of incorporation and restated by-laws, and intend to enter into indemnification agreements with any new directors and executive officers in the future. We have purchased and intend to maintain insurance on behalf of any person who is or was a director or officer against any loss arising from any claim asserted against him or her and incurred by him or her in any such capacity, subject to certain exclusions.

The foregoing discussion of our restated certificate of incorporation, restated by-laws, indemnification agreements and Delaware law is not intended to be exhaustive and is qualified in its entirety by such restated certificate of incorporation, restated by-laws, indemnification agreements or law.

Reference is made to our undertakings in Item 17 with respect to liabilities arising under the Securities Act. Reference is also made to the form of underwriting agreement filed as Exhibit 1.1 to this registration statement for the indemnification agreements between us and the underwriters.

Item 15. Recent Sales of Unregistered Securities.

Set forth below is information regarding shares of common stock, convertible notes and warrants issued, and options granted, by us within the past three years that were not registered under the Securities Act. Also included is the consideration, if any, received by us for such shares, convertible notes, warrants and options, and information relating to the section of the Securities Act, or rule of the Securities and Exchange Commission, under which exemption from registration was claimed. The following share and per share amounts reflect the share combination that occurred on August 20, 2013 in which every 10 shares of our common stock outstanding were combined into one share of our common stock and every 10 shares of our preferred stock outstanding were combined into one share of our preferred stock.

Issuances of Stock, Convertible Notes and Warrants

A. On March 17, 2011, one of our principal stockholders exercised warrants, issued in May 2001, to purchase 98 shares of our common stock at an exercise price of $0.030 per share. On August 1, 2011, one of our early investors exercised warrants, issued in March 2005 and June 2008, to purchase 138 shares of our common stock at an exercise price of $0.030 per share.

B. On June 1, 2011, we issued $26.0 million in aggregate principal amount of 8% convertible notes due 2016 to nine accredited investors. In accordance with their terms, the convertible notes have been accruing interest since the date of issuance. The principal amount plus accrued and unpaid interest of the convertible notes will automatically convert upon the closing of the offering made hereby into a number of shares of our common stock equal to the quotient obtained by dividing the unpaid principal amount of the convertible notes plus interest accrued but unpaid thereon, by 62.5% of the initial public offering price. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $26.0 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

II-2

C. On June 14, 2011, we issued $4.0 million in aggregate principal amount of convertible notes to four accredited investors on the same terms as those described above in Item B. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $4.0 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

D. On December 6, 2011, we issued $15.0 million in aggregate principal amount of 8% convertible notes due 2016 to 17 accredited investors. In accordance with their terms, the convertible notes have been accruing interest since the date of issuance. The principal amount plus accrued and unpaid interest of the convertible notes will automatically convert upon the closing of the offering made hereby into a number of shares of our common stock equal to the quotient obtained by dividing the unpaid principal amount of the convertible notes plus interest accrued but unpaid thereon, by 62.5% of the initial public offering price. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $15.0 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

E. On March 1, 2012, we issued $0.8 million in aggregate principal amount of convertible notes to 29 accredited investors on the same terms as those described above in Item D (but with $0.3 million maturing in 2014). Assuming an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $0.8 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

F. On June 11, 2012, we issued $9.6 million in aggregate principal amount of 8% convertible notes due 2016 to 18 accredited investors. In accordance with their terms, the convertible notes have been accruing interest since the date of issuance. The principal amount plus accrued and unpaid interest of the convertible notes will automatically convert upon the closing of the offering made hereby into a number of shares of our common stock equal to the quotient obtained by dividing the unpaid principal amount of the convertible notes plus interest accrued but unpaid thereon, by 62.5% of the initial public offering price. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $9.6 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

G. On July 17, 2012, we issued $0.6 million in aggregate principal amount of convertible notes to 26 accredited investors on the same terms as those described above in Item F (but with less than $0.1 million maturing in 2014). Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $0.6 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately             shares of our common stock.

H. On September 26, 2012, we issued $9.5 million in aggregate principal amount of convertible notes to seven accredited investors on the same terms as those described above in Item F. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $9.5 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

I. On October 5, 2012, we issued $0.5 million in aggregate principal amount of convertible notes to two accredited investors on the same terms as those described above in Item F. Assuming the convertible notes

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convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $0.5 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

J. On November 28, 2012, we issued $4.0 million in aggregate principal amount of convertible notes to three accredited investors on the same terms as those described above in Item F. On March 28, 2013 and May 6, 2013, these notes were cancelled in exchange for certain convertible notes and warrants described below in Items L, M, N and O.

K. On January 9, 2013, we issued $3.5 million in aggregate principal amount of convertible notes to 24 accredited investors on the same terms as those described above in Item F. On March 28, 2013 and May 6, 2013, these notes were cancelled in exchange for certain convertible notes and warrants described below in Items L, M, N and O.

L. On March 28, 2013, we issued $12.0 million in aggregate principal amount of 8% convertible notes due 2016 to 11 accredited investors. Of the $12.0 million in aggregate principal amount of convertible notes we issued, we issued $7.0 million in aggregate principal amount of convertible notes in exchange for convertible notes that we previously issued described above in Items J and K and $5.0 million in aggregate principal amount of convertible notes in exchange for cash. In accordance with their terms, the convertible notes have been accruing interest since the date of issuance. The principal amount plus accrued and unpaid interest of the convertible notes will automatically convert upon the closing of the offering made hereby into a number of shares of our common stock equal to the quotient obtained by dividing the unpaid principal amount of the convertible notes plus interest accrued but unpaid thereon, by 62.5% of the initial public offering price. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $12.0 million in principal amount of the outstanding convertible notes will convert into approximately              shares of our common stock.

M. In connection with the issuance of the convertible notes described above in Item L, on March 28, 2013, we issued warrants to purchase an aggregate of 46,253,855 shares of Series C preferred stock to 11 accredited investors. The warrants are exercisable at an exercise price of $0.0001 per share and are exercisable until March 28, 2023. Warrants to purchase an aggregate of 20,000 shares of Series C preferred were exercised on May 9, 2013 and May 13, 2013 as described below in Item P. We assume that the remainder of these warrants will be exercised in connection with this offering. Assuming all of these warrants are exercised for cash immediately prior to the consummation of this offering, and together with the conversion of the 20,000 shares Series C preferred stock previously issued upon the exercise of the warrants, the holders of the warrants will receive an aggregate of 46,253,855 shares of our common stock.

N. On May 6, 2013, we issued $10.5 million in aggregate principal amount of convertible notes to 43 accredited investors on the same terms as those described above in Item L. Of the $10.5 million in aggregate principal amount of convertible notes we issued, we issued $0.5 million in aggregate principal amount of convertible notes in exchange for convertible notes that we previously issued described above in Item K and $10.0 million in aggregate principal amount of convertible notes in exchange for cash. Assuming the convertible notes convert on             , 2014 and an initial public offering price of $         per share, which is the mid-point of the price range set forth on the cover page of the prospectus included in this registration statement, the $10.5 million in principal amount plus accrued interest on the outstanding convertible notes will convert into approximately              shares of our common stock.

O. In connection with the issuance of the convertible notes described above in Item N, on May 6, 2013, we issued warrants to purchase an aggregate of 40,764,332 shares of Series C preferred stock to 43 accredited investors. The warrants are exercisable at an exercise price of $0.0001 per share and are exercisable until

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March 28, 2023. We assume that all of these warrants will be exercised in connection with this offering. Assuming all of these warrants are exercised for cash immediately prior to the consummation of this offering, the holders of the warrants will receive an aggregate of 40,764,332 shares of our common stock.

P. On May 9, 2013 and May 13, 2013, we issued an aggregate of 20,000 shares of Series C preferred stock upon the exercise of warrants to purchase Series C preferred stock described above in Item M to two accredited investors.

Q. From April 15, 2011 through April 15, 2014, we issued an aggregate of 36,693 shares of our common stock to certain of our employees and consultants upon the exercise of stock options issued under the 2001 equity incentive plan, as amended.

Stock Option Grants

From April 15, 2011 through April 15, 2014, we granted stock options under our 2001 equity incentive plan, as amended, to purchase an aggregate of 80,112,212 shares of common stock, net of forfeitures, at a weighted-average exercise price of $0.100 per share, to certain of our employees, consultants and directors.

Securities Act Exemptions

The offers, sales and issuances of the securities described above were exempt from registration under the Securities Act in reliance on Section 4(a)(2) of the Securities Act and Rule 506 of Regulation D.

The grants of stock options described above under “— Stock Option Grants” were exempt from registration under the Securities Act in reliance on Rule 701 promulgated under the Securities Act as offers and sales of securities under compensatory benefit plans and contracts relating to compensation in compliance with Rule 701. Each of the recipients of securities in any transaction exempt from registration either received or had adequate access, through employment, business or other relationships, to information about us.

All certificates representing the securities issued in the transactions described in this Item 15 included appropriate legends setting forth that the securities had not been offered or sold pursuant to a registration statement and describing the applicable restrictions on transfer of the securities. There were no underwriters employed in connection with any of the transactions set forth in this Item 15.

Item 16. Exhibits and Financial Statement Schedules.

(a) See the Exhibit Index on the page immediately preceding the exhibits for a list of exhibits filed as part of this registration statement on Form S-1, which Exhibit Index is incorporated herein by reference.

(b) Financial Statement Schedules

All schedules have been omitted because they are not required or are not applicable or the required information is shown in the financial statements or notes thereto.

Item 17. Undertakings

(a) The undersigned registrant hereby undertakes to provide to the underwriters at the closing specified in the underwriting agreement certificates in such denominations and registered in such names as required by the underwriters to permit prompt delivery to each purchaser.

(b) Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the registrant pursuant to the provisions described under Item 14 above, or

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otherwise, the registrant has been advised that in the opinion of the Securities and Exchange Commission such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the event that a claim for indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.

(c) The undersigned registrant hereby undertakes that:

(1) For purposes of determining any liability under the Securities Act, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act shall be deemed to be part of this registration statement as of the time it was declared effective.

(2) For the purpose of determining any liability under the Securities Act, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.

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SIGNATURES

Pursuant to the requirements of the Securities Act, the Registrant certifies that it has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the city of Northborough, Massachusetts, on April 28, 2014.

ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
	Donald R. Young President and Chief Executive Officer

We, the undersigned officers and directors of Aspen Aerogels, Inc., hereby severally constitute and appoint Donald R. Young and John F. Fairbanks, and both or any one of them, our true and lawful attorneys-in-fact and agents, with full power of substitution and re-substitution in each of them for him and in his name, place and stead, and in any and all capacities, to sign any and all amendments (including post-effective amendments) to this registration statement, and any registration statement for the same offering that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act, and to file the same, with all exhibits thereto and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing necessary or desirable to be done in and about the premises, as fully to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that each of said attorneys-in-fact or his substitute or substitutes, may lawfully do or cause to be done by virtue hereof.

Pursuant to the requirements of the Securities Act, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature	Title	Date
/s/ Donald R. Young Donald R. Young	President, Chief Executive Officer and Director (principal executive officer)	April 28, 2014
/s/ John F. Fairbanks John F. Fairbanks	Vice President, Chief Financial Officer and Treasurer (principal financial officer and principal accounting officer)	April 28, 2014
/s/ Mark L. Noetzel Mark L. Noetzel	Chairman of the Board	April 28, 2014
/s/ P. Ramsay Battin P. Ramsay Battin	Director	April 28, 2014
/s/ Robert M. Gervis Robert M. Gervis	Director	April 28, 2014

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Signature	Title	Date
/s/ Craig A. Huff Craig A. Huff	Director	April 28, 2014
/s/ Steven R. Mitchell Steven R. Mitchell	Director	April 28, 2014
/s/ David J. Prend David J. Prend	Director	April 28, 2014
/s/ Richard F. Reilly Richard F. Reilly	Director	April 28, 2014

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EXHIBIT INDEX

Exhibit number	Description of Exhibit
1.1*	Form of underwriting agreement.
3.1.1	Fourth amended and restated certificate of incorporation of the Registrant, as amended.
3.1.2*	Certificate of amendment to the fourth amended and restated certificate of incorporation, as amended, of the Registrant.
3.2*	Form of restated certificate of incorporation of the Registrant to be filed with the Secretary of State of the State of Delaware upon completion of this offering.
3.3	By-laws of the Registrant, as amended.
3.4*	Form of restated by-laws of the Registrant to be effective upon completion of this offering.
4.1*	Form of common stock certificate.
4.2	Form of warrant to purchase common stock issued by the Registrant in connection with 2004 and 2005 financing arrangements, as amended and restated.
4.3	Form of warrant to purchase common stock issued by the Registrant in connection with the 2005 equity financing, as amended and restated.
4.4	Form of warrant to purchase common stock issued by the Registrant in connection with the 2008 reorganization.
4.5	Form of warrant to purchase common stock issued by the Registrant in connection with the 2008 financing.
4.6	Form of warrant to purchase common stock issued by the Registrant in connection with the 2010 subordinated note and warrant financing.
4.7	Form of warrant to purchase Series C preferred stock issued by the Registrant in connection with the 2013 convertible note and warrant financing.
4.8	Sixth amended and restated registration rights agreement, dated as of June 11, 2012, by and among the Registrant and the investors named therein, as amended.
5.1*	Opinion of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., counsel to the Registrant, with respect to the legality of securities being registered.
10.1.1@	2001 equity incentive plan, as amended.
10.1.2@	Form of incentive stock option agreement granted under 2001 equity incentive plan, as amended.
10.1.3@	Form of 2013 incentive stock option agreement for options issued in exchange for the forfeiture of
	options granted under 2001 equity incentive plan, as amended.
10.1.4@	Form of 2013 performance-based incentive stock option agreement granted under 2001 equity
	incentive plan, as amended.
10.1.5@	Form of non-qualified stock option agreement granted under 2001 equity incentive plan, as amended.
10.1.6@	Form of 2013 non-qualified stock option agreement for options issued in exchange for the forfeiture of options granted under 2001 equity incentive plan, as amended.
10.1.7@	Form of 2013 performance-based non-qualified stock option agreement granted under 2001 equity
	incentive plan, as amended.
10.1.8@	Form of 2013 independent director stock option agreement for options issued in exchange for the
	forfeiture of options granted under 2001 equity incentive plan, as amended.
10.1.9@	Form of 2013 performance-based independent director stock option agreement granted under 2001
	equity incentive plan, as amended.
10.2.1@*	2014 employee, director and consultant equity incentive plan.
10.2.2@*	Form of stock option agreement granted under 2014 employee, director and consultant equity incentive plan.
10.3	Multi-tenant industrial net lease, dated August 20, 2001, by and between the Registrant and Cabot II — MA1M03, LLC (as successor landlord to TMT290 Industrial Park, Inc.), as amended.
10.4	Loan and security agreement by and between the Registrant and Silicon Valley Bank, dated as of March 31, 2011, as amended.

Exhibit number	Description of Exhibit
10.5	Form of subordinated note issued by the Registrant in the 2010 subordinated note and warrant financing.
10.6	Form of convertible note issued by the Registrant in the June 2011 convertible note financing, as amended.
10.7	Form of convertible note issued by the Registrant in the December 2011 and March 2012 convertible note financing, as amended.
10.8	Form of convertible note issued by the Registrant in the June 2012, July 2012, September 2012, October 2012, November 2012 and January 2013 convertible note financing, as amended.
10.9	Form of convertible note issued by the Registrant in the March 2013 and May 2013 convertible note financing.
10.10@	Executive agreement, dated as of August 5, 2011, by and between the Registrant and Donald R. Young, as amended by the First Amendment thereto, dated as of October 23, 2012.
10.11@	Executive agreement, dated as of August 5, 2011, by and between the Registrant and John F. Fairbanks, as amended by the First Amendment thereto, dated as of November 6, 2012.
10.12@	Executive agreement, dated as of August 5, 2011, by and between the Registrant and George L. Gould, Ph.D.
10.13@	Executive agreement, dated as of August 5, 2011, by and between the Registrant and Kevin A. Schmidt.
10.14@	Executive agreement, dated as of January 30, 2012, by and between the Registrant and Corby C. Whitaker.
10.15@*	2014 corporate bonus plan and participation letters of executive officers.
10.16@*	Non-employee director compensation policy.
10.17#	Cross license agreement dated as of April 1, 2006 by and between Cabot Corporation and the Registrant, as amended.
21.1	Subsidiaries of the Registrant.
23.1	Consent of KPMG LLP.
23.2*	Consent of Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. (included in Exhibit 5.1).
23.3	Consent of Freedonia Custom Research, Inc.
24.1	Powers of Attorney (included on signature page).

* To be filed by amendment.

# Confidential treatment is being requested for portions of this exhibit.

@ Denotes management compensation plan or contract.

EX-3.1.1

Exhibit 3.1.1

FOURTH AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ASPEN AEROGELS, INC.

Aspen Aerogels, Inc., a corporation organized and existing under the laws of the State of Delaware, hereby certifies as follows:

1. The name of the Corporation is Aspen Aerogels, Inc. (the “Corporation”).

2. The Corporation filed, with the Secretary of State of the State of Delaware, its original Certificate of Incorporation on May 16, 2008, as amended by its First Amendment to Amended and Restated Certificate of Incorporation filed with the Secretary of State of the State of Delaware on August 14, 2009, as amended by its Second Amended and Restated Certificate of Incorporation filed with the Secretary of State of the State of Delaware on August 14, 2009, and as further amended by its Third Amended and Restated Certificate of Incorporation filed with the Secretary of State of the State of Delaware on September 22, 2010, as amended by a Certificate of Amendment of Third Amended and Restated Certificate of Incorporation of Aspen Aerogels, Inc. filed with the Secretary of State of the State of Delaware on November 14, 2012 (as so amended, the “Current Certificate of Incorporation”). The Corporation was formerly known as Aspen Merger Sub, Inc. and changed its name to Aspen Aerogels, Inc. on June 10, 2008.

3. This Fourth Amended and Restated Certificate of Incorporation (the “Certificate of Incorporation”) amends, restates and integrates the provisions of the Current Certificate of Incorporation and (i) was duly adopted by the board of directors of the Corporation (the “Board of Directors”) in accordance with the provisions of Section 245 of the General Corporation Law of the State of Delaware (the “DGCL”), (ii) was declared by the Board of Directors to be advisable and in the best interests of the Corporation and was directed by the Board of Directors to be submitted to and be considered by the stockholders of the Corporation entitled to vote thereon for approval by the affirmative vote of such stockholders in accordance with Section 242 of the DGCL and (iii) was duly adopted by a stockholder consent in lieu of a meeting of the stockholders, with the holders of a majority of the outstanding shares of the Corporation’s capital stock entitled to vote thereon, a majority of the outstanding capital stock of each class entitled to vote thereon as a class, a majority of the outstanding Series A Preferred Stock and Series B Preferred Stock (voting together as a single class) and two-thirds of the outstanding Series B Preferred Stock, consenting to the adoption of this Certificate of Incorporation in writing in accordance with the provisions of Sections 228 and 242 of the DGCL and the terms of the Current Certificate of Incorporation.

4. Capitalized terms used and not otherwise defined upon first usage herein shall have the meanings set forth in Section 4.3.7 of this Certificate of Incorporation.

5. The text of the Current Certificate of Incorporation is hereby amended and restated in its entirety to provide as follows:

ARTICLE I—NAME

The name of the Corporation is Aspen Aerogels, Inc.

ARTICLE II—REGISTERED OFFICE

The registered office of the Corporation in the State of Delaware is located at Corporation Service Company, in the City of Wilmington, County of New Castle. The name and address of its registered agent is Corporation Service Company, 2711 Centerville Road, Suite 400, Wilmington, Delaware 19808.

ARTICLE III—PURPOSE AND POWERS

The purpose of the Corporation is to engage in any lawful act or activity for which corporations may be organized under the DGCL. The Corporation shall have all power necessary or convenient to the conduct, promotion or attainment of such acts and activities.

ARTICLE IV—CAPITAL STOCK

4.1 AUTHORIZED SHARES.

The total number of shares of all classes of stock that the Corporation shall have the authority to issue is 2,534,537,410. Of such shares, 1,229,095,699 shall be Preferred Stock, having a par value of $0.00001 per share (“Preferred Stock”), and 1,305,441,711 shall be Common Stock, all of one class, having a par value of $0.00001 per share (“Common Stock”). The Preferred Stock may be issued from time to time in one or more series. The first series of Preferred Stock shall consist of 52,843,201 shares of Series A Convertible Preferred Stock (the “Series A Preferred Stock”). The second series of Preferred Stock shall consist of 16,010,292 shares of Series B Convertible Preferred Stock (the “Series B Preferred Stock”). The third series of Preferred Stock shall consist of 1,160,242,206 shares of Series C Convertible Preferred Stock (the “Series C Preferred Stock”). The Common Stock, the Series A Preferred Stock, the Series B Preferred Stock and the Series C Preferred Stock shall each be referred to herein as a “Series” of Stock. Except as otherwise expressly provided herein or as required by law, the holders of Preferred Stock and the holders of Common Stock shall vote together and not as separate classes.

4.2 COMMON STOCK.

4.2.1 Relative Rights.

The Common Stock shall be subject to all of the rights, privileges, preferences and priorities of the Preferred Stock as set forth in this Certificate of Incorporation. Each share of Common Stock shall have the same relative rights as and be identical in all respects to all the other shares of Common Stock.

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4.2.2 Dividends.

No dividend, whether in cash or property, shall be paid or declared, nor shall any other distribution be made, on the Common Stock, nor shall any shares of Common Stock be repurchased, redeemed, or otherwise acquired for value by the Corporation (except for acquisitions of Common Stock by the Corporation pursuant to (i) the Stockholders’ Agreement or any stock option agreement between the Corporation and its employees, (ii) agreements which permit the Corporation to repurchase such shares at cost upon termination of services to the Corporation, (iii) other agreements that are approved by a majority of the Board, or (iv) the exercise of the Corporation’s contractual right of first refusal upon a proposed transfer (whether pursuant to the Stockholders’ Agreement or otherwise), and in each case subject to the provisions of Section 4.3.4(c), unless and until (x) a dividend is paid to each stockholder of the Corporation in cash in an amount equal to one percent (1%) of the par value for each share of capital stock of the Corporation held by such stockholder (the “One Percent Return”) and (y) a dividend is paid in full on all outstanding shares of Preferred Stock in an amount at least equal per share (on an as-if-converted to Common Stock basis) to the amount proposed to be paid, set aside or declared for each share of Common Stock.

4.2.3 Dissolution, Liquidation, Winding Up.

In the event of any Liquidation, the holders of the Common Stock shall become entitled to receive the assets of the Corporation available for distribution in accordance with Section 4.3.2 of this Certificate of Incorporation.

4.2.4 Voting Rights.

Each holder of shares of Common Stock shall be entitled to attend all special and annual meetings of the stockholders of the Corporation and, together with the holders of all other classes of stock entitled to attend such meetings and to vote (except as to any class or series of stock having special voting rights), to cast one (1) vote for each outstanding share of Common Stock so held upon any matter or thing (including, without limitation, the election of one or more directors) properly considered and acted upon by the stockholders.

4.2.5 Increase or Decrease of Authorized Common Stock.

The number of authorized shares of Common Stock may be increased or decreased (but not below the number of shares of Common Stock then outstanding and the number of shares of Common Stock reserved pursuant to Section 4.3.5(g)(viii) below) by the affirmative vote of (i) the holders of capital stock of the Corporation representing a majority of the votes represented by all outstanding shares of capital stock of the Corporation entitled to vote (voting together on an as-if-converted-to Common Stock basis) and (ii) the Series C Majority Holders, in each case irrespective of the provisions of Section 242(b)(2) of the DGCL.

4.2.6 Redemption.

The Common Stock shall not be redeemable at the option of the holders thereof.

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4.3 PREFERRED STOCK.

The powers, designations, preferences and relative participating, optional or other rights of the Preferred Stock of the Corporation shall be as set forth in this Section 4.3. The Series C Preferred Stock shall be senior to the Series B Preferred Stock, to the Series A Preferred Stock and to the Common Stock, in all respects as to rights of payment and distribution (whether in cash, in kind or in other property or securities) whether by way of dividend, upon liquidation or otherwise. Except in the event of a Qualified Sale of the Corporation, the Series B Preferred Stock shall rank pari passu with the Series A Preferred Stock and senior to the Common Stock, in all respects as to rights of payment and distribution (whether in cash, in kind or in other property or securities) whether by way of dividend, upon liquidation or otherwise. Except in the event of a Qualified Sale of the Corporation, the Series A Preferred Stock shall rank pari passu with the Series B Preferred Stock and senior to the Common Stock, in all respects as to rights of payment and distribution (whether in cash, in kind or in other property or securities), whether by way of dividend, upon liquidation or otherwise. In the event of a Qualified Sale of the Corporation, in all respects as to rights of payment and distribution (whether in cash, in kind or in other property or securities) whether by way of dividend, upon liquidation or otherwise in respect of such Qualified Sale of the Corporation, (a) the Series B Preferred Stock shall be senior to the Series A Preferred Stock and senior to the Common Stock and (b) the Series A Preferred Stock shall be senior to the Common Stock. Each share of Series A Preferred Stock, each share of Series B Preferred Stock and each share of Series C Preferred Stock, respectively, shall have the same voting rights as all other shares of Series A Preferred Stock, all other shares of Series B Preferred Stock and all other shares of Series C Preferred Stock, respectively.

4.3.1 Dividends.

No dividend, whether in cash or property, shall be paid or declared, nor shall any other distribution be made, on the Preferred Stock unless and until a dividend is paid to each stockholder of the Corporation in cash in an amount equal to the One Percent Return. No dividend, whether in cash or property, shall be paid or declared, nor shall any other distribution be made, on the Series A Preferred Stock or the Series B Preferred Stock unless and until a dividend is paid in full on all outstanding shares of Series C Preferred Stock in an amount at least equal per share (on an as-if-converted to Common Stock basis) to the amount proposed to be paid, set aside or declared for each share of Series A Preferred Stock or Series B Preferred Stock, as applicable.

4.3.2 Liquidation.

Upon any Liquidation (other than a Qualified Sale Liquidation), distributions to the Corporation’s stockholders shall be made in the following manner:

(a) First, all of the stockholders of the Corporation shall be entitled to receive an amount per share equal to the par value for each share of capital stock of the Corporation held by such stockholder.

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(b) Second, all of the stockholders of the Corporation shall be entitled to receive an amount per share equal to the One Percent Return (unless previously paid) (together with the payment set forth in Section 4.3.2(a), the “Senior Liquidation Preference”).

(c) Third, following payment in full of the Senior Liquidation Preference, the holders of shares of Series C Preferred Stock (the “Series C Preferred Holders”) shall be entitled to receive, prior and in preference to any distribution of any of the assets of the Corporation (other than the Senior Liquidation Preference) to the holders of Common Stock, Series A Preferred Stock, Series B Preferred Stock and/or any Other Stock, an amount per share of Series C Preferred Stock equal to the Liquidation Amount for the Series C Preferred Stock. If upon any Liquidation, the assets of the Corporation available for distribution to its stockholders are insufficient to pay the Series C Preferred Holders the full Liquidation Amount for the Series C Preferred Stock pursuant to this paragraph (c), the Series C Preferred Holders shall share ratably in any distribution pursuant to this paragraph (c) in proportion to the aggregate Liquidation Amount for the Series C Preferred Stock to which each is entitled on account of the shares of Series C Preferred Stock then held by such Series C Preferred Holder.

(d) Fourth, following payment in full of the Senior Liquidation Preference and the Liquidation Amount payable to the Series C Preferred Holders as set forth in Section 4.3.2(c), the Junior Preferred Holders, ranking equally, shall be entitled to receive, prior and in preference to any distribution of any of the assets of the Corporation (other than the Senior Liquidation Preference and the Liquidation Amount payable to the Series C Preferred Holders as set forth in Section 4.3.2(c)) to the holders of Common Stock and/or any Other Stock, an amount per share equal to (i) in the case of the Series B Preferred Stock, the Liquidation Amount for the Series B Preferred Stock, and (ii) in the case of the Series A Preferred Stock, the Liquidation Amount for the Series A Preferred Stock. If upon any Liquidation, the assets of the Corporation available for distribution to its stockholders are insufficient to pay the holders of shares of Series B Preferred Stock (the “Series B Preferred Holders”) the full Liquidation Amount for the Series B Preferred Stock or the holders of shares of Series A Preferred Stock (the “Series A Preferred Holders”) the full Liquidation Amount for the Series A Preferred Stock pursuant to this paragraph (d), the Junior Preferred Holders shall share ratably in any distribution pursuant to this paragraph (d) in proportion to the aggregate Liquidation Amount for the Series B Preferred Stock or Series A Preferred Stock, as applicable, to which each is entitled on account of the shares of Junior Preferred Stock then held by such Junior Preferred Holder.

(e) Fifth, following payment in full to all of the stockholders of the Corporation of the Senior Liquidation Preference, to the Series C Preferred Holders of the Liquidation Amounts set forth in Section 4.3.2(c), and to the Junior Preferred Holders of the Liquidation Amounts set forth in Section 4.3.2(d) or Section 4.3.2(f), as applicable, the Series A Preferred Holders, the Series B Preferred Holders, the Series C Preferred Holders and the holders of Common Stock shall together receive any remaining assets of the Corporation then available for distribution to the Corporation’s stockholders, ratably on an as-if-converted-to Common Stock basis;

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(f) Notwithstanding the foregoing provisions in this Section 4.3.2, in the event of a Liquidation as a result of a Qualified Sale of the Corporation (a “Qualified Sale Liquidation”):

(i) First, all of the stockholders of the Corporation shall be entitled to receive an amount per share equal to the par value for each share of capital stock of the Corporation held by such stockholder.

(ii) Second, all of the stockholders of the Corporation shall be entitled to receive an amount per share equal to the One Percent Return (unless previously paid).

(iii) Third, following payment in full of the Senior Liquidation Preference, the Series C Preferred Holders shall be entitled to receive, prior and in preference to any distribution of any of the assets of the Corporation (other than the Senior Liquidation Preference) to the holders of Common Stock, Series A Preferred Stock, Series B Preferred Stock and/or any Other Stock, an amount per share of Series C Preferred Stock equal to the Liquidation Amount for the Series C Preferred Stock. If upon any Liquidation, the assets of the Corporation available for distribution to its stockholders are insufficient to pay the Series C Preferred Holders the full Liquidation Amount for the Series C Preferred Stock pursuant to this paragraph (iii), the Series C Preferred Holders shall share ratably in any distribution pursuant to this paragraph (iii) in proportion to the aggregate Liquidation Amount for the Series C Preferred Stock to which each is entitled on account of the shares of Series C Preferred Stock then held by such Series C Preferred Holder.

(iv) Fourth, following payment in full of the Senior Liquidation Preference and the Liquidation Amount payable to the Series C Preferred Holders, the Series B Preferred Holders shall be entitled to receive, prior and in preference to any distribution of any of the assets of the Corporation (other than the Senior Liquidation Preference and the Liquidation Amount payable to the Series C Preferred Holders) to the holders of Common Stock, Series A Preferred Stock and/or any Other Stock, an amount per share of Series B Preferred Stock equal to the Qualified Sale Liquidation Amount for the Series B Preferred Stock. If upon any Qualified Sale Liquidation, the assets of the Corporation available for distribution to its stockholders are insufficient to pay the Series B Preferred Holders the full Qualified Sale Liquidation Amount for the Series B Preferred Stock pursuant to this paragraph (f)(iv), the Series B Preferred Holders shall share ratably in any distribution pursuant to this paragraph (f)(iv) in proportion to the aggregate Qualified Sale Liquidation Amount for the Series B Preferred Stock to which each is entitled on account of the shares of Series B Preferred Stock then held by such Series B Preferred Holder.

(v) Fifth, following payment in full of the Senior Liquidation Preference, the Liquidation Amount payable to the Series C Preferred Holders and the Qualified Sale Liquidation Amount payable to the Series B Preferred Holders as set forth in Section 4.3.2(f)(iv), the Series A Preferred Holders shall be entitled to receive, prior and in preference to any distribution of any of the assets of the Corporation (other than the Senior Liquidation Preference, the Liquidation Amount payable to the Series C Preferred Holders and the Qualified Sale Liquidation Amount payable to the Series B Preferred Holders as set forth in Section 4.3.2(f)(iv)) to the holders of Common Stock and/or any Other Stock, an amount per share of Series A Preferred Stock equal to the Qualified Sale Liquidation Amount for the Series A Preferred Stock. If upon any

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Qualified Sale Liquidation, the assets of the Corporation available for distribution to its stockholders are insufficient to pay the Series A Preferred Holders the full Qualified Sale Liquidation Amount for the Series A Preferred Stock pursuant to this paragraph (f)(v), the Series A Preferred Holders shall share ratably in any distribution pursuant to this paragraph (f)(v) in proportion to the aggregate Qualified Sale Liquidation Amount for the Series A Preferred Stock to which each is entitled on account of the shares of Series A Preferred Stock then held by such Series A Preferred Holder.

(vi) Sixth, following payment in full to all of the stockholders of the Corporation of the Senior Liquidation Preference, the Liquidation Amount payable to the Series C Preferred Holders and the Qualified Sale Liquidation Amount payable to the Junior Preferred Holders, the Series A Preferred Holders, the Series B Preferred Holders and the holders of Common Stock shall together receive any remaining assets of the Corporation then available for distribution to the Corporation’s stockholders, ratably on an as-if-converted-to Common Stock basis;

provided, that, if the aggregate amount which the Series B Preferred Holders are entitled to receive under Section 4.3.2(f) shall exceed an amount per share equal to two times (2x) the Original Issuance Price for the Series B Preferred Stock (the “Series B Maximum Participation Amount”), each Series B Preferred Holder shall be entitled to receive upon such Liquidation on account of the shares of Series B Preferred Stock then held by such Series B Preferred Holder the greater of (i) the Series B Maximum Participation Amount and (ii) the amount such holder would have received on account of the shares of Series B Preferred Stock then held by such Series B Preferred Holder if all shares of Series B Preferred Stock had been converted into Common Stock immediately prior to such Liquidation;

provided further, that if the aggregate amount which the Series A Preferred Holders are entitled to receive under Section 4.3.2(f) shall exceed an amount per share equal to two times (2x) the Original Issuance Price for the Series A Preferred Stock (the “Series A Maximum Participation Amount”), each Series A Preferred Holder shall be entitled to receive upon such Liquidation on account of the shares of Series A Preferred Stock then held by such Series A Preferred Holder the greater of (i) the Series A Maximum Participation Amount and (ii) the amount such holder would have received on account of the shares of Series A Preferred Stock then held by such Series A Preferred Holder if all shares of Series A Preferred Stock had been converted into Common Stock immediately prior to such Liquidation.

(g) The Corporation shall give each Preferred Holder written notice (a “Proposal Notice”) of any impending or proposed Liquidation not later than thirty (30) days prior to the stockholders’ meeting called to approve such impending or proposed Liquidation, if applicable, or thirty (30) days prior to the closing or occurrence of such impending or proposed Liquidation, whichever is earlier. Such Proposal Notice shall describe the material terms and conditions of the impending or proposed Liquidation and the provisions of this Section 4.3.2 as they apply to the allocation of proceeds to stockholders from such impending or proposed Liquidation. Upon any material changes to the terms of such impending or proposed Liquidation after the date the Corporation has given a related Proposal Notice, the Corporation shall give

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each Preferred Holder prompt written notice of such material change(s) (a “Supplemental Notice”). The impending or proposed Liquidation shall in no event be consummated sooner than thirty (30) days after the Corporation has given a related Proposal Notice or sooner than ten (10) days after the Corporation has given such Supplemental Notice; provided, however, that such periods may be shortened by approval or consent of the Series C Majority Holders, provided that in any case the notice periods may not be shorter than the later of (i) ten (10) days after the Proposal Notice, (ii) five (5) days after any Supplemental Notice and (iii) five (5) days after any such approval or consent. Any Proposal Notice or Supplemental Notice required by this Section 4.3.2 shall be deemed given (a) with respect to any holder of record having an address (as appearing on the books of the Corporation) within the United States or Canada only, if by nationally recognized overnight courier, on the next business day following such dispatch, (b) with respect to any holder of record having an address (as appearing on the books of the Corporation) outside the United States or Canada, if by commercially recognized international courier, on the third business day after the posting thereof and (c) with respect to any holder of record having an address (as appearing on the books of the Corporation) within the United States only, if by United States mail, on the third business day after the posting thereof when deposited, postage prepaid, and addressed to the holder of record at its address appearing on the books of the Corporation. The rights conferred upon the Preferred Holders under this Section 4.3.2 are supplemental to and not in replacement of the provisions of Section 4.3.4(c).

(h) If the consideration received by the Corporation in a Liquidation is other than cash, its value will be deemed its fair market value as reasonably determined in good faith by the Board of Directors. Any securities shall be valued as follows:

(i) Securities not subject to investment letter or other similar restrictions on free marketability covered by (ii) below:

(A) if traded on a securities exchange, the value shall be deemed to be the average of the closing prices of the securities on such exchange over the thirty (30) day period ending three (3) days prior to the closing;

(B) if actively traded over-the-counter, the value shall be deemed to be the average of the closing bid or sale prices (whichever is applicable) over the thirty (30) day period ending three (3) days prior to the closing; and

(C) if there is no active public market, the value shall be the fair market value thereof, as reasonably determined in good faith by the Board of Directors.

(ii) The method of valuation of securities subject to investment letter or other restrictions on free marketability (other than restrictions arising solely by virtue of a shareholder’s status as an affiliate or former affiliate) shall be to make an appropriate discount from the market value determined as above in clauses (i) (A), (B) or (C) to reflect the approximate fair market value thereof, as reasonably determined in good faith by the Board of Directors.

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(i) In the event the requirements of this Section 4.3.2 are not complied with, the Corporation shall forthwith either (i) cause the closing or consummation of the Liquidation to be postponed until such time as the requirements of this Section 4.3.2 shall have been complied with or (ii) cancel such transaction, in which event, the rights, preferences and privileges of the Preferred Holders shall in all respects be preserved.

4.3.3 Redemption.

The Preferred Stock shall not be redeemable at the option of the holders thereof.

4.3.4 Voting Rights.

(a) In addition to the rights provided by law or in the Corporation’s By-laws, each share of Preferred Stock shall entitle the holder thereof to such number of votes as shall equal the number of whole shares of Common Stock into which such share of Preferred Stock is then convertible pursuant to Section 4.3.5 at the record date for the determination of stockholders entitled to vote or, if no record date is established, at the date such vote is taken. The Preferred Holders shall be entitled to vote on all matters as to which holders of Common Stock shall be entitled to vote, in the same manner and with the same effect as such holders of Common Stock, voting together with the holders of Common Stock as one class. Except as specifically required by law or by this Certificate of Incorporation, with respect to any matter upon which the Preferred Holders shall be entitled to vote, there shall be no series voting and the Series A Preferred Stock, the Series B Preferred Stock and the Series C Preferred Stock shall vote together as one class.

(b) The holders of record of the shares of Common Stock and Preferred Stock, exclusively and voting together as a single class, shall be entitled to elect the directors of the Corporation.

(c) Notwithstanding anything in this Certificate of Incorporation to the contrary, at any time when shares of Series C Preferred Stock are outstanding, the Corporation shall not, either directly or indirectly by amendment, merger, consolidation or otherwise, alter or change the powers, preferences or special rights of the shares of the Series C Preferred Stock set forth in this Certificate of Incorporation so as to affect them adversely without the affirmative vote or prior written consent of the Series C Majority Holders, consenting or voting separately as a class. This Section 4.3.4(c) shall be interpreted in accordance with Section 242(b)(2) of the DGCL, as in effect from time to time. In addition, at any time when shares of Series C Preferred Stock are outstanding, the Corporation shall not, either directly or indirectly by amendment, merger, consolidation or otherwise, do any of the following (in addition to any other vote required by law or the Certificate of Incorporation) without the affirmative vote or prior written consent of the Series C Majority Holders, consenting or voting (as the case may be) separately as a class:

(i) increase or decrease the number of authorized shares of Common Stock or Preferred Stock or increase the number of shares reserved under the Corporation’s equity incentive plans and other stock option agreements approved by the Board above 24,845,806 shares (including by adoption of a new equity incentive plan and as adjusted for stock dividends, stock splits and similar events);

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(ii) create or authorize the creation of, or issue or obligate itself to issue, shares of any new class or series of stock, or any other equity securities, or any other securities convertible, exercisable or exchangeable into equity securities of the Corporation (including by way of reclassification of any existing securities);

(iii) reclassify, alter or amend any existing security of the Corporation;

(iv) declare or pay any dividends or make any other distributions on or with respect to the Common Stock or the Preferred Stock;

(v) consummate a Liquidation or a Sale of the Corporation or consent to any of the foregoing;

(vi) declare a voluntary bankruptcy of the Corporation;

(vii) take any action that would modify, amend, alter or repeal any provision of, or add any provision to, the Corporation’s Certificate of Incorporation or the Corporation’s Bylaws or take any action that would alter or change the powers, preferences or special rights of, or the restrictions provided for the benefit of, the Common Stock or the Preferred Stock;

(viii) redeem or repurchase any shares of its capital stock (other than (A) redemptions pursuant to any stock option agreement between the Corporation and its employees or consultants approved by the Board, (B) the repurchase of capital stock, at cost, from a member of the Corporation’s management in connection with the cessation of such employment pursuant to a duly adopted employment, management, restricted stock or stock repurchase agreement or (C) redemptions pursuant to the Arcapita Agreement;

(ix) change the number of directors authorized to serve on the Board;

(x) acquire all or substantially all of the business, properties, assets or equity securities of any Person;

(xi) assume or incur any indebtedness for borrowed money in excess of $500,000;

(xii) make a fundamental change to the business of the Corporation; or

(xiii) issue or obligate itself to issue any shares of Preferred Stock other than under, and pursuant to the terms and conditions of, the 2013 Purchase Agreement.

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4.3.5 Conversion.

(a) Upon the terms set forth in this Section 4.3.5, each Preferred Holder shall have the right, at such holder’s option, at any time and from time to time, to convert such shares of Preferred Stock into the number of fully paid and non-assessable shares of Common Stock equal to the product obtained by multiplying, for each such Series of Preferred Stock, (i) the number of shares of Preferred Stock to be converted by (ii) the Conversion Ratio of such share. The Preferred Holders may exercise the conversion right pursuant to this Section 4.3.5(a) by delivering to the Corporation the certificate for the shares to be converted, duly endorsed or assigned in blank or to the Corporation (if required by it), accompanied by written notice stating that the holder elects to convert such shares and stating the name or names (with address(es)) in which the certificate or certificates for the shares of Common Stock are to be issued. Conversion shall be deemed to have been effected on the date when such delivery is made (the “Conversion Date”). Upon a conversion of any shares of Preferred Stock pursuant to this Section 4.3.5(a), no accrued or declared and unpaid dividends on such shares of Preferred Stock shall be paid.

(b) All shares of Preferred Stock shall automatically be converted into shares of Common Stock (determined pursuant to Section 4.3.5(a) above), based on the then-effective Conversion Ratio of such share, at any time (i) upon the affirmative vote or prior written consent of the Series C Majority Holders, consenting or voting (as the case may be) separately as a class or (ii) immediately upon the closing of a QPO. A conversion of Preferred Stock into shares of Common Stock pursuant to this Section 4.3.5(b) shall be referred to as an “Automatic Conversion”.

(c) [Reserved]

(d) Notwithstanding any other provision herein to the contrary, upon the occurrence of an Automatic Conversion, the outstanding shares of Preferred Stock shall be converted automatically without any further action by the holders of such shares and whether or not the certificates representing such shares are surrendered to the Corporation or its transfer agent pursuant to Section 4.3.5(a) above; provided, however, that the Corporation shall not be obligated to issue certificates evidencing the shares of Common Stock issuable upon such conversion unless the certificates evidencing such shares of Preferred Stock are either delivered to the Corporation or its transfer agent as provided in Section 4.3.5(a), or the holder notifies the Corporation or its transfer agent that such certificates have been lost, stolen or destroyed and executes an agreement satisfactory to the Corporation to indemnify the Corporation from any loss incurred by it in connection with such certificates. The Conversion Date for the shares of Preferred Stock converted pursuant to an Automatic Conversion shall be deemed to be the date of the consummation of the QPO or the date of the delivery of the applicable election notice. In the case of an Automatic Conversion effected by reason of a QPO, such conversion shall be conditioned upon the closing with the underwriters of the sale of securities pursuant to such offering, in which event the Person(s) entitled to receive the Common Stock upon conversion of the Preferred Stock shall not be deemed to have converted such Preferred Stock until immediately prior to the closing of such sale of securities. Upon an Automatic Conversion, no accrued or declared and unpaid dividends on the Preferred Stock shall be paid.

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(e) At the time of the conversion of any shares of Preferred Stock into Common Stock under Section 4.3.5(a) or 4.3.5(b), the Corporation shall issue and deliver to the holders of such shares, upon the written order of such holders, to the place designated by such holders, a certificate or certificates for the number of full shares of Common Stock to which such holders are entitled, together with, if applicable, a cash amount in respect of any fractional interest in a share of Common Stock required pursuant to Section 4.3.5(f) below. The Person in whose name the certificate or certificates for Common Stock are to be issued shall be deemed to have become a holder of Common Stock of record on the Conversion Date unless the transfer books of the Corporation are closed on that date, in which event such Person shall be deemed to have become a holder of Common Stock of record on the next succeeding date on which the transfer books are open, but the rights of the holder of the shares of Preferred Stock so converted shall cease on the Conversion Date. Upon conversion of only a portion of the number of shares covered by a certificate representing shares of Preferred Stock surrendered for conversion, the Corporation shall issue and deliver upon the written order of the holder of the certificate so surrendered for conversion, at the expense of the Corporation, a new certificate covering the number of shares of Preferred Stock representing the unconverted portion of the certificate so surrendered.

(f) Upon conversion, the Corporation shall not issue fractional shares of its Common Stock and shall distribute cash in lieu of such fractional shares in an amount equal to the product of (i) the price of one share of Common Stock as reasonably determined in good faith by the Board and (ii) such fractional interest. The number of shares of Common Stock issuable upon conversion of Preferred Stock shall be computed on the basis of the aggregate number of shares of Preferred Stock to be converted.

(g) The Conversion Ratio for the Series A Preferred Stock, the Series B Preferred Stock and the Series C Preferred Stock shall be subject to adjustment from time to time as follows:

(i) If, at any time after the Original Issuance Date, the number of shares of Common Stock outstanding is increased by a stock dividend payable in shares of Common Stock or by a subdivision or split-up of shares of Common Stock, then, following the record date for the determination of holders of Common Stock entitled to receive such stock dividend, subdivision or split-up, the Conversion Ratio of such share of the Preferred Stock shall be appropriately increased so that the number of shares of Common Stock issuable on conversion of each such share of Preferred Stock shall be increased in proportion to such increase in outstanding shares.

(ii) If, at any time after the Original Issuance Date, the number of shares of Common Stock outstanding is decreased by a combination of the outstanding shares of Common Stock, then, following the record date for such combination, the Conversion Ratio of such share of the Preferred Stock shall be appropriately decreased so that the number of shares of Common Stock issuable on conversion of each such share of Preferred Stock shall be decreased in proportion to such decrease in outstanding shares.

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(iii) In the event of any capital reorganization of the Corporation, any reclassification of the stock of the Corporation (other than a change in par value or from par value to no par value or from no par value to par value or as a result of a stock dividend or subdivision, split-up or combination of shares), or any consolidation or merger of the Corporation, each share of Preferred Stock shall after such reorganization, reclassification, consolidation or merger be convertible into the kind and number of shares of stock or other securities or property of the Corporation or of the corporation resulting from such consolidation or surviving such merger to which the holder of the number of shares of Common Stock deliverable (immediately prior to the time of such reorganization, reclassification, consolidation or merger) upon conversion of such share of Preferred Stock would have been entitled upon such reorganization, reclassification, consolidation or merger. The provisions of this clause (iii) shall similarly apply to successive reorganizations, reclassifications, consolidations or mergers.

(iv) No adjustment in the Conversion Ratio of the Preferred Stock shall be required unless such adjustment would require an increase or decrease of at least 0.01% in the Conversion Ratio; provided, however, that any adjustments not required to be made by virtue of this sentence shall be carried forward and taken into account in any subsequent adjustment. All calculations under Sections 4.3.5(g)(i) through 4.3.5(g)(iii) above shall be made to the nearest one one-hundred thousandth (1/100,000) of a share.

(v) In any case in which the provisions of this Section 4.3.5(g) shall require that an adjustment become effective immediately after a record date of an event, the Corporation may defer until the occurrence of such event (A) issuing to the holder of any share of Preferred Stock converted after such record date and before the occurrence of such event the shares of capital stock issuable upon such conversion by reason of the adjustment required by such event in addition to the shares of capital stock issuable upon such conversion before giving effect to such adjustments, and (B) if applicable, paying to such holder any amount in cash in lieu of a fractional share of capital stock pursuant to Section 4.3.5(f); provided, however, that the Corporation shall deliver to such holder an appropriate instrument evidencing such holder’s right to receive such additional shares.

(vi) Whenever the Conversion Ratio of the Preferred Stock shall be adjusted as provided in Section 4.3.5(g), the Corporation shall make available for inspection during regular business hours, at its principal executive offices or at such other place as may be designated by the Corporation, a statement, signed by its chief executive officer, showing in detail the facts requiring such adjustment and the Conversion Ratio for the Preferred Stock that shall be in effect after such adjustment. The Corporation shall also cause a copy of such statement to be sent by first class certified mail, return receipt requested and postage prepaid, to each Preferred Holder affected by the adjustment at such holder’s address appearing on the Corporation’s records. Where appropriate, such copy may be given in advance and may be included as part of any notice required to be mailed under the provisions of Section 4.3.5(g)(vii) below.

(vii) If the Corporation shall propose to take any action of the types described in clauses (i), (ii) or (iii) of this Section 4.3.5(g), the Corporation shall give notice to each Preferred Holder, which notice shall specify the record date, if any, with respect to any such action and the date on which such action is to take place. Such notice shall also set forth such facts with respect thereto as shall be reasonably necessary to

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indicate the effect of such action (to the extent such effect may be known at the date of such notice) on the Conversion Ratio or Liquidation Amount, as applicable, and the number, kind or class of shares or other securities or property which shall be deliverable or purchasable upon the occurrence of such action or deliverable upon conversion of shares of Preferred Stock. In the case of any action which would require the fixing of a record date, such notice shall be given at least twenty (20) days prior to the date so fixed, and in case of all other action, such notice shall be given at least thirty (30) days prior to the taking of such proposed action. Failure to give such notice, or any defect therein, shall not affect the legality or validity of any such action.

(viii) The Corporation shall at all times keep reserved, free from preemptive rights, out of its authorized but unissued shares of Common Stock, solely for the purpose of effecting the conversion of the Series A Preferred Stock, the Series B Preferred Stock and the Series C Preferred Stock or the conversion of any other securities issued pursuant to clause (iii) of this Section 4.3.5(g), sufficient shares of Common Stock to provide for the conversion of all outstanding shares of Series A Preferred Stock, Series B Preferred Stock and Series C Preferred Stock.

(ix) [Reserved.]

(x) The Corporation shall not, by amendment of its Certificate of Incorporation or through any reorganization, transfer of assets, spin-off, consolidation, merger, dissolution, issue or sale of securities or any other voluntary action or inaction, avoid or seek to avoid the observance or performance of any of the terms to be observed or performed hereunder by the Corporation, but shall at all times in good faith assist in the carrying out of all the provisions of this Section 4.3.5(g) and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the Preferred Holders against impairment.

(h) Upon conversion of all of the shares of the Series A Preferred Stock, all of the shares of the Series B Preferred Stock and all of the shares of the Series C Preferred Stock into Common Stock, all of the provisions herein governing such shares of Preferred Stock, as applicable, shall terminate with respect to the Corporation.

4.3.6 [Reserved]

4.3.7 Definitions.

As used in this Certificate of Incorporation, the following terms have the following meanings:

(a) “2013 Purchase Agreement” means that certain Note and Warrant Purchase Agreement dated on or about March 27, 2013.

(b) “Affiliate” means, (1) with respect to any Person, any of (a) a director, officer or stockholder holding 5% or more of the capital stock (on a fully diluted basis) of such Person, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling or descendant of any director or officer of such Person) and (c) any other Person that, directly or

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indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with, another Person or (2) in any event, any Person meeting the definition of “Affiliate” set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation, the possession, directly or indirectly, of the power to direct the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise.

(c) “Arcapita Agreement” means the Amended and Restated Stockholder Agreement between the Corporation and Arcapita Ventures I Limited dated August 14, 2009;

(d) “Board” means the Board of Directors of the Corporation.

(e) “Conversion Ratio” means:

(i) In the event of a Qualified Sale Liquidation:

(A) as to each share of Series A Preferred Stock, a ratio of 1.0; and

(B) as to each share of Series B Preferred Stock, a ratio of 1.0.

(ii) Other than in the event of a Qualified Sale Liquidation:

(A) as to each share of Series A Preferred Stock issued on August 14, 2009, a ratio of 1.31291262;

(B) as to each share of Series A Preferred Stock issued on September 10, 2009, a ratio of 1.30651698;

(C) as to each share of Series A Preferred Stock issued on September 14, 2009, a ratio of 1.30556948;

(D) as to each share of Series B Preferred Stock issued on September 22, 2010, a ratio of 1.49755364;

(E) as to each share of Series B Preferred Stock issued on October 20, 2010, a ratio of 1.48236116; and

(F) as to each share of Series C Preferred Stock, a ratio of 1.0.

(f) “Convertible Securities” means securities or obligations that are exercisable for, convertible into or exchangeable for shares of Common Stock. The term includes options, warrants or other rights to subscribe for or purchase Common Stock or to subscribe for or purchase other securities that are convertible into, directly or indirectly, or exchangeable for Common Stock.

(g) “Junior Preferred Holders” means the holders of the Series B Preferred Stock together with the holders of the Series A Preferred Stock.

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(h) “Liquidation” means any single transaction or series of related transactions involving any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Corporation. A Sale of the Corporation shall be deemed to be a Liquidation for all purposes of Section 4.3.2.

(i) “Liquidation Amount” means: (i) as to each share of Series A Preferred Stock (A) issued on August 14, 2009, an amount equal to $0.046053572; (B) issued on September 10, 2009, an amount equal to $0.045842252; and (C) issued on September 14, 2009, an amount equal to $0.045810921; (ii) as to each share of Series B Preferred Stock (A) issued on September 22, 2010, an amount equal to $0.098246892; and (B) issued on October 20, 2010, an amount equal to $0.097744893; and (iii) as to each share of Series C Preferred Stock, an amount equal to $0.034475560; in each such case, as adjusted equitably for stock dividends, stock splits, combinations and the like.

(j) “One Percent Return” is defined in Section 4.2.2.

(k) “Original Issuance Date” means the date that the first share of Series C Preferred Stock is issued by the Corporation.

(l) “Original Issuance Price” means, (i) as to each share of Series A Preferred Stock, $0.583602172 (as adjusted for stock splits, stock dividends, combinations or other similar events) and (ii) as to each share of Series B Preferred Stock, $1.33680238 (as adjusted for stock splits, stock dividends, combinations or other similar events).

(m) “Other Stock” means Common Stock or any other class of the Corporation’s capital stock ranking junior to the Series C Preferred Stock, the Series B Preferred Stock or the Series A Preferred Stock, as the case may be, with respect to the distribution of assets upon the liquidation, dissolution or winding up of the Corporation.

(n) “Person” shall be construed broadly and shall include an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization, or a governmental entity (or any department, agency, or political subdivision thereof).

(o) “Preferred Holder” means any holder of Preferred Stock.

(p) “QPO” means the first underwritten public offering (underwritten by a reputable underwriter of national reputation) of shares of Common Stock registered pursuant to the Securities Act involving aggregate proceeds to the Corporation of at least $60,000,000 or in which the holders of a majority of the outstanding Senior Subordinated Convertible Notes of the Corporation issued pursuant to the 2013 Purchase Agreement elect to convert such notes into shares of Common Stock.

(q) “Qualified Purchaser” means any Person who submitted a term sheet for the acquisition of the Corporation between January 1, 2013, and March 13, 2013, in connection with the formal sales process conducted by the Corporation during such period.

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(r) “Qualified Sale of the Corporation” means any Sale of the Corporation to a Qualified Purchaser that is consummated on or before the Qualified Sale Date.

(s) “Qualified Sale Date” means September 13, 2013.

(t) “Qualified Sale Liquidation” is defined in Section 4.3.2(f).

(u) “Qualified Sale Liquidation Amount” means: (i) as to each share of Series A Preferred Stock (A) issued on August 14, 2009, an amount equal to $0.752574932; (B) issued on September 10, 2009, an amount equal to $0.749121700; and (C) issued on September 14, 2009, an amount equal to $0.748609709; (ii) as to each share of Series B Preferred Stock (A) issued on September 22, 2010, an amount equal to $1.605481301; and (B) issued on October 20, 2010, an amount equal to $1.597277987; and (iii) as to each share of Series C Preferred Stock, an amount equal to $0.034475560; in each such case, as adjusted equitably for stock dividends, stock splits, combinations and the like.

(v) “Sale of the Corporation” means (i) except as a result of the exercise of the Warrants by the Warrant holders or the conversion of either the Notes or the Prior Notes by the holders of such notes (the terms in this clause (i) as defined in the 2013 Purchase Agreement), the sale, transfer or other disposition in one transaction or a series of related transactions of fifty percent (50%) or more of the then-outstanding voting power of the Corporation to a Person or group of Persons that is not an Affiliate of the Corporation or a permitted successor or transferee of any Stockholder, (excluding, for the avoidance of doubt, the sale of shares by the Corporation for capital raising purposes) other than a transaction or series of transactions (a) effected exclusively to change the domicile of the Corporation, (b) that merges or consolidates the Corporation with or into a wholly-owned subsidiary of the Corporation, or (c) in which the holders of the voting securities of the Corporation outstanding immediately before such transaction continue to retain (either by such voting securities remaining outstanding or by such voting securities being converted into voting securities of the surviving entity), on account of shares in the Corporation held by such holders immediately before such transaction, at least a majority of the total voting power represented by the voting securities of the Corporation or such surviving entity outstanding immediately after such transaction or series of transactions; (ii) a sale, transfer, lease, exclusive license or other conveyance or disposition, in one transaction or a series of related transactions, of all or substantially all of the assets of the Corporation and its subsidiaries taken as a whole, or (iii) the sale or disposition (whether by merger or otherwise) of one or more subsidiaries of the Corporation if substantially all of the assets of the Corporation and its subsidiaries taken as a whole are held by such subsidiary or subsidiaries, except in the case of clauses (ii) and (iii) where such sale, transfer, lease, exclusive license or other conveyance or disposition is to a wholly owned subsidiary of the Corporation.

(w) “Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations promulgated thereunder.

(x) “Senior Liquidation Preference” is defined in Section 4.3.2(b).

(y) “Series A Preferred Holders” is defined in Section 4.3.2(d).

(z) “Series B Preferred Holders” is defined in Section 4.3.2(d).

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(aa) “Series C Liquidation Preference” means an amount equal to $30,000,000.

(bb) “Series C Majority Holders” means the holders of the majority of the then outstanding shares of Series C Preferred Stock.

(cc) “Series C Preferred Holders” is defined in Section 4.3.2(c).

(dd) “Stockholders’ Agreement” means the Sixth Amended and Restated Stockholders’ Agreement dated as of March 27, 2013, among the Corporation and certain stockholders of the Corporation, as the same may be further amended, modified or supplemented from time to time.

ARTICLE V—BOARD OF DIRECTORS

The number of directors of the Corporation shall be such number as from time to time shall be fixed by, or in the manner provided in, the By-laws of the Corporation. Unless and except to the extent that the By-laws of the Corporation shall otherwise require, the election of directors of the Corporation need not be by written ballot. Except as otherwise provided in this Certificate of Incorporation, each director of the Corporation shall be entitled to one vote per director on all matters voted or acted upon by the Board of Directors.

ARTICLE VI—LIABILITY OF DIRECTORS

No director of the Corporation shall be personally liable to the Corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except to the extent such exemption from liability or limitation thereof is not permitted under the DGCL as the same exists or may hereafter be amended, provided, that this provision shall not eliminate or limit the liability of a director: (a) for any breach of the director’s duty of loyalty to the Corporation or its stockholders; (b) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law; (c) under Section 174 of the DGCL; or (d) for any transaction from which the director derived an improper personal benefit. If the DGCL is amended, at any time after approval by the stockholders of this Article VI, to authorize corporation action further eliminating or limiting the personal liability of directors, then the liability of a director of the Corporation shall be eliminated or limited to the fullest extent permitted by the DGCL, as so amended. Any repeal or modification of this Article VI shall be prospective only and shall not adversely affect any right or protection of, or any limitation on the liability of, a director of the Corporation existing at, or arising out of facts or incidents occurring prior to, the effective date of such repeal or modification. To the fullest extent permitted by applicable law, the Corporation is authorized to provide indemnification of (and, in its discretion, advancement of expenses to) agents of the Corporation (and any other persons to which DGCL permits the Corporation to provide indemnification) through bylaw provisions, agreements with such agents or other persons, vote of stockholders or disinterested directors or otherwise, in excess of the indemnification and advancement otherwise permitted by Section 145 of the DGCL, subject only to limits created by applicable provisions of the DGCL (statutory or non-statutory), with respect to actions for breach of duty to the Corporation, its stockholders, and others. Any amendment, repeal or modification of the foregoing provisions of this Article VI shall not adversely affect any right or protection of a director, officer, agent, or other person existing at the time of, or increase the liability of any director of the Corporation with respect to any acts or omissions of such director, officer or agent occurring prior to, such amendment, repeal or modification.

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ARTICLE VII—DURATION OF CORPORATION

The Corporation is to have perpetual existence.

ARTICLE VIII—AMENDMENT OF BYLAWS

In furtherance and not in limitation of the powers conferred by the laws of Delaware, the Board of Directors of the Corporation is authorized and empowered to adopt, alter, amend and repeal the By-laws of the Corporation in any manner not inconsistent with the laws of Delaware or Section 4.3.4 of this Certificate of Incorporation.

ARTICLE IX—MEETINGS OF STOCKHOLDERS; CORPORATE BOOKS

Meetings of the stockholders may be held within or without the State of Delaware, as the By-laws may provide. The books of the Corporation may be kept (subject to any provision contained in the statutes) outside the State of Delaware at such place or places as may be designated from time to time by the Board of Directors or in the By-Laws of the Corporation.

ARTICLE X—AMENDMENT OF CERTIFICATE OF INCORPORATION

This Certificate of Incorporation may be amended in the manner now or hereafter prescribed by statute and in accordance with the provisions hereof. This Article X shall be interpreted in accordance with Section 242(b)(2) of the DGCL, as in effect from time to time.

ARTICLE XI—CABOT SUBORDINATION

Notwithstanding any other provision hereof, all payments on account of any shares of the Corporation’s capital stock, whether principal, interest, dividends or otherwise, and whether paid in cash or other property, are subject to the provisions of Article II of the Settlement Agreement and First Amendment to Cross License Agreement dated as of September 21, 2007, by and between Cabot Corporation and the Corporation, as in effect as of the date hereof, which provisions are hereby expressly incorporated by reference thereto.

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I, Donald R. Young, the President of the Corporation, for the purpose of amending and restating the Corporation’s certificate of incorporation pursuant to the General Corporation Law of the State of Delaware, do make this certificate, hereby declaring and certifying that this is my act and deed on behalf of the Corporation, and the facts herein stated are true, and accordingly hereunto set my hand this 28th day of March, 2013.

ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
Name: Donald R. Young
Title: President

CERTIFICATE OF AMENDMENT

TO

FOURTH AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

ASPEN AEROGELS, INC.

Aspen Aerogels, Inc., a corporation organized and existing under the laws of the State of Delaware, hereby certifies as follows:

1. The name of the corporation (the “Corporation”) is Aspen Aerogels, Inc.

2. The Corporation filed its Fourth Amended and Restated Certificate of Incorporation with the Secretary of State of the State of Delaware on March 28, 2013 (the “Certificate of Incorporation”).

3. This Certificate of Amendment to Fourth Amended and Restated Certificate of Incorporation (this “Amendment”) amends the Certificate of Incorporation as provided herein and (i) was duly adopted by the board of directors of the Corporation (the “Board of Directors”) in accordance with the provisions of Section 242 of the General Corporation Law of the State of Delaware (the “DGCL”), (ii) was declared by the Board of Directors to be advisable and in the best interests of the Corporation and was directed by the Board of Directors to be submitted to and be considered by the stockholders of the Corporation entitled to vote thereon for approval by the affirmative vote of such stockholders in accordance with Section 242 of the DGCL and (iii) was duly adopted by stockholder consent in lieu of a meeting of the stockholders, with the holders of a majority of the outstanding shares of the Corporation’s capital stock entitled to vote thereon, and a majority of the outstanding capital stock of each class entitled to vote thereon as a class, consenting to the adoption of this Amendment in writing in accordance with the provisions of Sections 228 and 242 of the DGCL and the terms of the Certificate of Incorporation. As required by Section 228 of the DGCL, the Corporation has given written notice of this Amendment to the stockholders of the Corporation who did not consent in writing to such amendment.

4. The Certificate of Incorporation is hereby amended as follows:

(a) Article IV is hereby amended by adding the following language as an introductory paragraph to such Article IV:

“Upon the filing and effectiveness (the “Effective Time”) pursuant to the DGCL of this Certificate of Amendment to the Certificate of Incorporation of the Corporation, every ten (10) shares of Common Stock and of each Series of Preferred Stock (as such terms are defined below) issued and outstanding or held by the Corporation in treasury stock as of the Effective Time shall be, and hereby are, combined, converted and exchanged into one (1) issued and outstanding share of Common Stock and applicable Series of Preferred Stock, respectively (the “Reverse Stock Split”), without any change in the par value of such shares, automatically and without any action by any holder thereof and whether or not the certificates representing such shares are surrendered to the Corporation. Each certificate which immediately prior to the Effective Time

represented one or more shares of Common Stock or Series of Preferred Stock shall thereafter, automatically and without any action by any holder thereof, represent that number of shares of Common Stock or applicable Series of Preferred Stock, as the case may be, into which such shares shall have been combined. Upon surrender by a holder of Common Stock or Preferred Stock of a certificate or certificates for Common Stock or Preferred Stock duly endorsed, at the office of the Corporation or its agent for such purpose, the Corporation shall, as soon as practicable thereafter, issue and deliver at such office to such holder of Common Stock or Preferred Stock a certificate or certificates for the number of shares of Common Stock or Preferred Stock to which such holder shall be entitled as aforesaid.”

(b) Section 4.1 of Article IV is hereby amended by deleting Section 4.1 of Article IV in its entirety and inserting the following in lieu thereof:

“4.1 AUTHORIZED SHARES.

The total number of shares of all classes of stock that the Corporation shall have the authority to issue is 327,330,643. Of such shares, 122,909,642 shall be Preferred Stock, having a par value of $0.00001 per share (“Preferred Stock”), and 204,421,001 shall be Common Stock, all of one class, having a par value of $0.00001 per share (“Common Stock”). The Preferred Stock may be issued from time to time in one or more series. The first series of Preferred Stock shall consist of 5,284,347 shares of Series A Convertible Preferred Stock (the “Series A Preferred Stock”). The second series of Preferred Stock shall consist of 1,601,053 shares of Series B Convertible Preferred Stock (the “Series B Preferred Stock”). The third series of Preferred Stock shall consist of 116,024,242 shares of Series C Convertible Preferred Stock (the “Series C Preferred Stock”). The Common Stock, the Series A Preferred Stock, the Series B Preferred Stock and the Series C Preferred Stock shall each be referred to herein as a “Series” of Stock. Except as otherwise expressly provided herein or as required by law, the holders of Preferred Stock and the holders of Common Stock shall vote together and not as separate classes.”

(c) The figure “24,845,806” in Section 4.3.4(c)(i) of Article IV is hereby deleted and replaced with the figure “76,361,297”.

5. This Amendment has been duly adopted in accordance with the provisions of Sections 141, 228, and 242 of the General Corporation Law of the State of Delaware.

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I, Donald R. Young, the President of the Corporation, for the purpose of amending the Corporation’s certificate of incorporation pursuant to the General Corporation Law of the State of Delaware, do make this certificate, hereby declaring and certifying that this is my act and deed on behalf of the Corporation, and the facts herein stated are true, and accordingly hereunto set my hand this 7th day of August, 2013.

ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
Name: Donald R. Young
Title: President

CERTIFICATE OF AMENDMENT

OF

FOURTH AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

ASPEN AEROGELS, INC.

It is hereby certified that:

1. The name of the corporation (the “Corporation”) is Aspen Aerogels, Inc.

2. The Corporation’s Fourth Amended and Restated Certificate of Incorporation, as amended (the “Certificate of Incorporation”), is hereby amended as follows:

(a) Section 4.1 of Article IV of the Certificate of Incorporation is hereby amended by deleting Section 4.1 of Article IV in its entirety and inserting the following in lieu thereof:

“The total number of shares of all classes of stock that the Corporation shall have the authority to issue is 333,797,872. Of such shares, 122,909,642 shall be Preferred Stock, having a par value of $0.00001 per share (“Preferred Stock”), and 210,888,230 shall be Common Stock, all of one class, having a par value of $0.00001 per share (“Common Stock”). The Preferred Stock may be issued from time to time in one or more series. The first series of Preferred Stock shall consist of 5,284,347 shares of Series A Convertible Preferred Stock (the “Series A Preferred Stock”). The second series of Preferred Stock shall consist of 1,601,053 shares of Series B Convertible Preferred Stock (the “Series B Preferred Stock”). The third series of Preferred Stock shall consist of 116,024,242 shares of Series C Convertible Preferred Stock (the “Series C Preferred Stock”). The Common Stock, the Series A Preferred Stock, the Series B Preferred Stock and the Series C Preferred Stock shall each be referred to herein as a “Series” of Stock. Except as otherwise expressly provided herein or as required by law, the holders of Preferred Stock and the holders of Common Stock shall vote together and not as separate classes.”

(b) The figure “76,361,297” in Section 4.3.4(c)(i) of Article IV of the Certificate of Incorporation is hereby deleted and replaced with the figure “82,828,526”.

3. The amendment of the Certificate of Incorporation herein certified has been duly adopted in accordance with the provisions of Sections 141, 228, and 242 of the General Corporation Law of the State of Delaware.

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IN WITNESS WHEREOF, the Corporation has caused this Certificate of Amendment to be signed by its President this 20th day of December 2013.

ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
Name: Donald R. Young
Title: President

EX-3.3

Exhibit 3.3

ASPEN MERGER SUB, INC.

BY-LAWS

ARTICLE 1

OFFICES

SECTION 1.01 Registered Office. The registered office of Aspen Merger Sub, Inc., (the “Corporation”) in the State of Delaware shall be at c/o Corporation Service Company, 2711 Centerville Road, Suite 400, Wilmington, Delaware 19808. The name of the resident agent at such address is Corporation Service Company.

SECTION 1.02 Other Offices. The Corporation may also have an office at such other place or places either within or without the State of Delaware as the Board of Directors may from time to time determine or the business of the Corporation require.

ARTICLE 2

MEETINGS OF STOCKHOLDERS

SECTION 2.01 Place of Meetings. All meetings of the Stockholders of the Corporation shall be held at such place either within or without the State of Delaware as shall be fixed by the Board of Directors and specified in the respective notices or waivers of notice of said meetings.

SECTION 2.02 Annual Meetings. (a) The annual meeting of the stockholders for the election of directors and for the transaction of such other business as may come before the meeting shall be held at the principal office of the Corporation in the State of Delaware, or such place as shall be fixed by the Board of Directors, at two o’clock in the afternoon, local time, on the second Tuesday in February in each year, if not a legal holiday at the place where such meeting is to be held, and if a legal holiday, then on the next succeeding business day not a legal holiday at the same hour. (b) In respect of the annual meeting for any particular year the Board

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of Directors may, by resolution fix a different day, time or place (either within or without the State of Delaware) for the annual meeting. (c) If the election of directors shall not be held on the day designated herein or the day fixed by the Board, as the case may be, for any annual meeting, or on the day of any adjourned session thereof, the Board of Directors shall cause the election to be held at a special meeting as soon thereafter as conveniently may be. At such special meeting the stockholders may elect the directors and transact other business with the same force and effect as at an annual meeting duly called and held.

SECTION 2.03 Special Meetings. A special meeting of the stockholders for any purpose or purposes may be called at any time by the President or Chairman, if any, or by order of the Board of Directors and must be called by the Secretary upon the request in writing of any stockholder holding of record at least twenty-five percent of the outstanding shares of stock of the Corporation entitled to vote at such meeting.

SECTION 2.04 Notice of Meetings. (a) Except as otherwise required by statute, notice of each annual or special meeting of the stockholders shall be given to each stockholder of record entitled to vote at such meeting not less than ten days nor more then fifty days before the day on which the meeting is to be held by delivering written notice thereof to him personally or by mailing such notice, postage prepaid, addressed to him at his post-office address last shown in the records of the Corporation or by transmitting notice thereof to him at such address by facsimile, electronic mail or any other available method. Every such notice shall state the time and place of the meeting and, in case of a special meeting, shall state briefly the purposes thereof. (b) Notice of any meeting of stockholders shall not be required to be given to any stockholder who shall attend such meeting in person or by proxy or who shall in person or by attorney thereunto authorized, waive such notice in writing or by facsimile, electronic mail, or any other available method either before or after such meeting. Notice of any adjourned meeting of the stockholders shall not be required to be given except when expressly required by law.

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SECTION 2.05 Quorum. (a) At each meeting of the stockholders, except where otherwise provided by statute, the Certificate of Incorporation or these By-Laws, the holders of record of a majority of the issued and outstanding shares of stock of the Corporation entitled to vote at such meeting, present in person or represented by proxy, shall constitute a quorum for the transaction of business. (b) In the absence of a quorum a majority in interest of the stockholders of the Corporation entitled to vote, present in person or represented by proxy or, in the absence of all such stockholders, any officer entitled to preside at, or act as secretary of, such meeting, shall have the power to adjourn the meeting from time to time, until stockholders holding the requisite amount of stock shall be present or represented. At any such adjourned meeting at which a quorum shall be present any business may be transacted which might have been transacted at the meeting as originally called.

SECTION 2.06 Organization. At each meeting of the stockholders the President, the Chairman, if any, any Vice President, or any other officer designated by the Board of Directors, shall act as chairman, and the Secretary or an Assistant Secretary of the Corporation, or in the absence of the Secretary and all Assistant Secretaries, a person whom the chairman of such meeting shall appoint shall act as secretary of the meeting and keep the minutes thereof.

SECTION 2.07 Voting. (a) Except as otherwise provided by law or by the Certificate of Incorporation or these By-Laws, at every meeting of the stockholders each stockholder shall be entitled to one vote, in person or by proxy, for each share of capital stock of the Corporation registered in his name on the books of the Corporation:

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(i) on the date fixed pursuant to Section 9.03 of these By-Laws as the record date for the determination of stockholders entitled to vote at such meeting; or

(ii) if no such record date shall have been fixed, then the record date shall be at the close of business on the day next preceding the day on which notice of such meeting is given.

(b) Persons holding stock in a fiduciary capacity shall be entitled to vote the shares so held. In the case of stock held jointly by two or more executors, administrators, guardians, conservators, trustees or other fiduciaries, such fiduciaries may designate in writing one or more of their number to represent such stock and vote the shares so held, unless there is a provision to the contrary in the instrument, if any, defining their powers and duties. (c) Persons whose stock is pledged shall be entitled to vote thereon until such stock is transferred on the books of the Corporation to the pledgee, and thereafter only the pledgee shall be entitled to vote. (d) Any stockholder entitled to vote may do so in person or by his proxy appointed by an instrument in writing subscribed by such stockholder or by his attorney thereunto authorized, or by facsimile, electronic mail or any other available method delivered to the secretary of the meeting; provided, however, that no proxy shall be voted after three years from its date, unless said proxy provides for a longer period. (e) At all meetings of the stockholders, all matters (except where other provision is made by law or by the Certificate of Incorporation or these By-Laws) shall be decided by the vote of a majority in interest of the stockholders entitled to vote thereon, present in person or by proxy, at such meeting, a quorum being present.

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SECTION 2.08 Inspectors. The chairman of the meeting may at any time appoint one or more inspectors to serve at a meeting of the stockholders. Such inspectors shall decide upon the qualifications of voters, accept and count the votes for and against the questions presented, report the results of such votes, and subscribe and deliver to the secretary of the meeting a certificate stating the number of shares of stock issued and outstanding and entitled to vote thereon and the number of shares voted for and against the questions presented. The inspectors need not be stockholders of the Corporation, and any director or officer of the Corporation may be an inspector on any question other than a vote for or against his election to any position with the Corporation or on any other question in which he may be directly interested. Before acting as herein provided each inspector shall subscribe an oath faithfully to execute the duties of an inspector with strict impartiality and according to the best of his ability.

SECTION 2.09 List of Stockholders. (a) It shall be the duty of the Secretary or other officer of the Corporation who shall have charge of its stock ledger to prepare and make, or cause to be prepared and made, at least ten days before every meeting of the stockholders, a complete list of the stockholders entitled to vote thereat, arranged in alphabetical order and showing the address of each stockholder and the number of shares registered in the name of stockholder. Such list shall be open during ordinary business hours to the examination of any stockholder for any purpose germane to the meeting for a period of at least ten days prior to the election, either at a place within the city where the meeting is to be held, which place shall be specified in the notice of the meeting or, if not so specified, at the place where the meeting is to be held. (b) Such list shall be produced and kept at the time and place of the meeting during the whole time thereof and may be inspected by any stockholder who is present. (c) Upon the willful neglect or refusal of the directors to produce such list at any meeting for the election of directors they shall be ineligible for election to any office at such meeting. (d) The stock ledger shall be conclusive evidence as to who are the stockholders entitled to examine the stock ledger and the list of stockholders required by this Section 2.09 on the books of the Corporation or to vote in person or by proxy at any meeting of stockholders.

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ARTICLE 3

BOARD OF DIRECTORS

SECTION 3.01 General Powers. The business, property and affairs of the Corporation shall be managed by the Board of Directors.

SECTION 3.02 Number, Qualifications and Term of Office. (a) The number of directors of the Corporation which shall constitute the whole Board of Directors shall be such number, not less than the minimum number allowed under the laws of the State of Delaware nor more than seven (7) as from time to time shall be fixed by the Board of Directors; (b) a director need not be a stockholder. Each director shall hold office until the annual meeting of the stockholders next following his election and until his successor shall have been elected and shall qualify, or until his death, or until he shall resign, or until he shall have been removed in the manner hereinafter provided.

SECTION 3.03 Election of Directors. At each meeting of the stockholders for the election of directors at which a quorum is present, the persons, not exceeding the authorized number of directors, receiving the greatest number of votes of the stockholders entitled to vote thereon, present in person or by proxy, shall be the directors. In the case of any increases in the number of directors, the additional director or directors may be elected either at the meeting of the Board of Directors or of the stockholders at which such increase is voted, or at any subsequent annual, regular or special meeting of the Board of Directors or stockholders.

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SECTION 3.04 Quorum and Manner of Acting. (a) Except as otherwise provided by statute, by the Certificate of Incorporation or by an agreement among the holders of at least a majority of the issued and outstanding stock of the Corporation, a majority of the directors at the time in office shall constitute a quorum for the transaction of business at any meeting and the affirmative action of a majority of the directors present at any meeting at which a quorum is present shall be required for the taking of any action by the Board of Directors. (b) In the event one or more of the directors shall be disqualified to vote at such meeting, then the required quorum shall be reduced by one for each such director so disqualified; provided, however, that in no event shall the quorum as adjusted be less than one third of the total number of directors. (c) In the absence of a quorum at any meeting of the Board such meeting need not be held; or a majority of the directors present thereat or, if no director be present, the Secretary may adjourn such meeting from time to time until a quorum shall be present. Notice of any adjourned meeting need not be given, except as otherwise required by statute or by the Certificate of Incorporation.

SECTION 3.05 Offices, Place of Meeting and Records. The Board of Directors may hold meetings, have an office or offices and keep the books and records of the Corporation at such place or places within or without the State of Delaware as the Board may from time to time determine. The place of meeting shall be specified or fixed in the respective notices or waivers of notice thereof, except where otherwise provided by statute, by the Certificate of Incorporation or these By-Laws.

SECTION 3.06 Annual Meeting. The Board of Directors shall meet for the purpose of organization, the election of officers and the transaction of other business, as soon as practicable following each annual election of directors. Such meeting shall be called and held at the place and time specified in the notice or waiver of notice thereof as in the case of a special meeting of the Board of Directors.

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SECTION 3.07 Regular Meetings. Regular meetings of the Board of Directors shall be held at such places and at such times as the Board shall from time to time by resolution determine. If any day fixed for a regular meeting shall be a legal holiday at the place where the meeting is to be held, then the meeting which would otherwise be held on that day shall be held at said place at the same hour on the next succeeding business day. Notice of regular meetings need not be given.

SECTION 3.08 Special Meetings; Notice. Special meetings of the Board of Directors shall be held whenever called by the President or Chairman, if any, or by any two of the directors. Notice of each such meeting shall be mailed to each director, addressed to him at his residence or usual place of business, at least two days before the day on which the meeting is to be held, or shall be sent to him at his residence or at such place of business by facsimile, electronic mail, or other available means, or shall be delivered personally or by telephone, not later than one day before the day on which the meeting is to be held. Each such notice shall state the time and place of the meeting but need not state the purposes thereof except as otherwise herein expressly provided. Notice of any such meeting need not be given to any director, however, if waived by him in writing or by facsimile, electronic mail or otherwise, whether before or after such meeting shall be held, or if he shall be present at such meeting.

SECTION 3.09 Organization. At each meeting of the Board of Directors the President or Chairman, if any, or, in their absence, a director chosen by a majority of the directors present shall act as chairman. The Secretary or, in his absence an Assistant Secretary or, in the absence of the Secretary and all Assistant Secretaries, a person whom the chairman of such meeting shall appoint shall act as secretary of such meeting and keep the minutes thereof.

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SECTION 3.10 Order of Business. At all meetings of the Board of Directors business shall be transacted in the order determined by the Board.

SECTION 3.11 Removal of Directors. Except as otherwise provided in the Certificate of Incorporation or in these By-Laws, any director may be removed, either with or without cause, at any time, by the affirmative vote of the holders of record of a majority of the issued and outstanding stock entitled to vote for the election of directors of the Corporation given at a special meeting of the stockholders called and held for the purpose; and the vacancy in the Board caused by any such removal may be filled by such stockholders at such meeting in the manner hereinafter provided or, if the stockholders at such meeting shall fail to fill such vacancy, as in these By-Laws provided.

SECTION 3.12 Resignation. Any director of the Corporation may resign at any time by giving written notice of his resignation to the Board of Directors, the President, the Chairman, if any, or the Secretary of the Corporation. Such resignation shall take effect at the date of receipt of such notice or at any later time specified therein; and, unless otherwise specified therein, the acceptance of such resignation shall not be necessary to make it effective.

SECTION 3.13 Vacancies. Any vacancy in the Board of Directors caused by death, resignation, removal, disqualification, an increase in the number of directors, or any other cause may be filled by majority action of the remaining directors then in office, though less than a quorum, or by the stockholders of the Corporation at the next annual meeting or any special meeting called for the purpose, and each director so elected shall hold office until the next annual election of directors and until his successor shall be duly elected and qualified or until his death or until he shall resign or shall have been removed in the manner herein provided.

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SECTION 3.14 Compensation. Each director, in consideration of his serving as such, shall be entitled to receive from the Corporation such amount per annum or such fees for attendance at directors’ meetings, or both, as the Board of Directors shall from time to time determine, together with reimbursement for the reasonable expenses incurred by him in connection with the performance of his duties; provided that nothing herein contained shall be construed to preclude any director from serving the Corporation or its subsidiaries in any other capacity and receiving proper compensation therefor.

ARTICLE 4

COMMITTEES

SECTION 4.01 Executive Committee. The Board of Directors may, by resolution or resolutions passed by a majority of the whole Board, appoint an Executive Committee to consist of not less than two members of the Board of Directors, including the President or Chairman, if any, and shall designate one of the members as its chairman. Notwithstanding any limitation on the size of the Executive Committee, the Committee may invite members of the Board to attend one at a time at its meetings. For the purpose of the meeting he so attends, the invited director shall be entitled to vote on matters considered at such meeting and shall receive the Executive Committee fee for such attendance. At any time one additional director may be invited to an Executive Committee meeting in addition to the rotational invitee and in such case such additional invitee shall also be entitled to vote on matters considered at such meeting and shall receive the Executive Committee fee for such attendance.

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Each member of the Executive Committee shall hold office, so long as he shall remain a director, until the first meeting of the Board of Directors held after the next annual meeting of the Board of Directors held after the next annual election of directors and until his successor is duly appointed and qualified. The chairman of the Executive Committee or, in his absence, a member of the Committee chosen by a majority of the members present shall preside at meetings of the Executive Committee and the Secretary or an Assistant Secretary of the Corporation, or such other person as the Executive Committee shall from time to time determine, shall act as secretary of the Executive Committee.

The Board of Directors, by action of the majority of the whole Board, shall fill vacancies in the Executive Committee.

SECTION 4.02 Powers. During the intervals between the meetings of the Board of Directors, the Executive Committee shall have and may exercise all of the powers of the Board of Directors in all cases in which specific directions shall not have been given by the Board of Directors.

SECTION 4.03 Procedure; Meetings; Quorum. The Executive Committee shall fix its own rules of procedure subject to the approval of the Board of Directors, and shall meet at such times and at such place or places as may be provided by such rules. At every meeting of the Executive Committee the presence of a majority of all the members shall be necessary to constitute a quorum and the affirmative vote of a majority of the members present shall be necessary for the adoption by it of any resolution. In the absence of a quorum at any meeting of the Executive Committee such meeting need not be held, or a majority of the members present thereat or, if no members be present, the secretary of the meeting may adjourn such meeting from time to time until a quorum be present.

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SECTION 4.04 Compensation. Each member of the Executive Committee shall be entitled to receive from the Corporation such fee, if any, as shall be fixed by the Board of Directors, together with reimbursement for the reasonable expenses incurred by him in connection with the performance of his duties.

SECTION 4.05 Other Board Committees. The Board of Directors may from time to time, by resolution passed by a majority of the whole Board, designate one or more committees in addition to the Executive Committee, each committee to consist of two or more of the directors of the Corporation. Any such committee, to the extent provided in the resolution or in the By-Laws of the Corporation, shall have and may exercise the powers of the Board of Directors in the management of the business and affairs of the Corporation.

A majority of all the members of any such committee may determine its action and fix the time and place of its meetings, unless the Board of Directors shall otherwise provide. The Board of Directors shall have power to change the members of any committee at any time, to fill vacancies and to discharge any such committee, either with or without cause, at any time.

SECTION 4.06 Alternates. The President or Chairman, if any, may designate one or more directors as alternate members of any committee who may act in the place and stead of members who temporarily cannot attend any such meeting.

SECTION 4.07 Additional Committees. The Board of Directors may from time to time create such additional committees of directors, officers, employees or other persons designated by it (or any combination of such persons) for the purpose of advising the Board, the Executive Committee and the officers and employees of the Corporation in all such matters as the Board shall deem advisable and with such functions and duties as the Board shall by resolutions prescribe.

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A majority of all the members of any such committee may determine its action and fix the time and place of its meetings, unless the Board of Directors shall otherwise provide. The Board of Directors shall have the power to change the members of any committee at any time, to fill vacancies and to discharge any such committee, either with or without cause, at any time.

ARTICLE 5

ACTION BY CONSENT

SECTION 5.01 Consent by Directors. Any action required or permitted to be taken at any meeting of the Board of Directors or of any committee thereof may be taken without a meeting if prior to such action a written consent thereto is signed by all members of the Board or of such committee, as the case may be, and such written consent is filed with the minutes of the proceedings of the Board or such committee.

SECTION 5.02 Consent by Stockholders. Any action required or permitted to be taken at any meeting of the stockholders may be taken without a meeting upon the written consent of the holders of shares of stock entitled to vote who hold the number of shares which in the aggregate are at least equal to the percentage of the total vote required by statute or the Certificate of Incorporation or these By-Laws for the proposed corporate action.

ARTICLE 6

OFFICERS

SECTION 6.01 Number. The principal officers of the Corporation shall be a President, a Vice President, a Treasurer and a Secretary. In addition, there may be such other or subordinate officers, agents and employees as may be appointed in accordance with the provisions of Section 6.03. Any two or more offices may be held by the same person, except that if there are two or more officers of the Corporation, the office of Secretary shall be held by a person other than the person holding the office of President.

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SECTION 6.02 Election, Qualifications and Term of Office. Each officer of the Corporation, except such officers as may be appointed in accordance with the provisions of Section 6.03, shall be elected annually by the Board of Directors and shall hold office until his successor shall have been duly elected and qualified, or until his death, or until he shall have resigned or shall have been removed in the manner herein provided.

SECTION 6.03 Other Officers. The Corporation may have such other officers, agents, and employees as the Board of Directors may deem necessary, including a Chairman, a Chief Executive Officer, a Chief Financial Officer, a Controller, one or more Assistant Controllers, one or more Assistant Treasurers and one or more Assistant Secretaries, each of whom shall hold office for such period, have such authority, and perform such duties as the Board of Directors, any committee of the Board designated by it to so act, or the President or Chairman, if any, may from time to time determine. The Board of Directors may delegate to any principal officer the power to appoint or remove any such subordinate officers, agents or employees.

SECTION 6.04 Removal. Any officer may be removed, either with or without cause, by the vote of a majority of the whole Board of Directors or, except in case of any officer elected by the Board of Directors, by any committee of officers upon whom the power of removal may be conferred by the Board of Directors.

SECTION 6.05 Resignation. Any officer may resign at any time by giving written notice to the Board of Directors or the President or Chairman, if any, or the Secretary of the Corporation. Any such resignation shall take effect at the date of receipt of such notice or at any later time specified therein; and, unless otherwise specified therein, the acceptance of such resignation shall not be necessary to make it effective.

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SECTION 6.06 Vacancies. A vacancy in any office because of death, resignation, removal, disqualification or any other cause shall be filled for the unexpired portion of the term in the manner prescribed in these By-Laws for regular election or appointment to such office.

SECTION 6.07 Chairman of the Board. The Chairman of the Board, if any, shall be a director and shall preside at all meetings of the Board of Directors and shareholders. Subject to determination by the Board of Directors, the Chairman, if any, shall have general executive powers and such specific powers and duties as from time to time may be conferred or assigned by the Board of Directors.

SECTION 6.08 President. Subject to definition by the Board of Directors, the President shall have general executive powers and such specific powers and duties as from time to time may be conferred upon or assigned to him by the Board of Directors or any committee of the Board designated by it to so act. In the absence of the President, the Vice President shall preside at all meetings of the stockholders.

SECTION 6.09 Vice President. Each Vice President, if any, shall have such powers and perform such duties as from time to time may be conferred upon or assigned to him by the Board of Directors or any committee of the Board designated by it to so act, or by the President or Chairman, if any. In the absence of the President or Chairman, if any, a Vice President shall preside at all meetings of the stockholders.

SECTION 6.10 Treasurer. The Treasurer shall have charge and custody of, and be responsible for, all funds and securities of the Corporation, and shall deposit all such funds to the credit of the Corporation in such banks, trust companies or other depositories as shall be selected in accordance with the provisions of these By-Laws; he shall disburse the funds of the Corporation as may be ordered by the Board of Directors or any committee of the Board

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designated by it so to act, or by the President or Chairman, if any, making proper vouchers for such disbursements, and shall render to the Board of Directors or the stockholders, whenever the Board may require him so to do, a statement of all his transactions as Treasurer and of the financial condition of the Corporation; and, in general, he shall perform all the duties as from time to time may be assigned to him by the Board of Directors or any committee of the Board designated by it so to act, or by the President or Chairman, if any.

SECTION 6.11 Secretary. The Secretary shall record or cause to be recorded in books provided for the purpose the minutes of the meetings of the stockholders, the Board of Directors, and all committees of which a secretary shall not have been appointed; shall see that all notices are duly given in accordance with the provisions of these By-Laws and as required by law; shall be custodian of all corporate records (other than financial) and of the seal of the Corporation and see that the seal is affixed to all documents the execution of which on behalf of the Corporation under its seal is duly authorized in accordance with the provisions of these By-Laws; shall keep, or cause to be kept, the list of stockholders as required by Section 2.09, which include the post-office addresses of the stockholders and the number of shares held by them, respectively, and shall make or cause to be made, all proper changes therein, shall see that the books, reports, statements, certificates and all other documents and records required by law are properly kept and filed; and, in general, shall perform all duties incident to the office of Secretary and such other duties as may from time to time be assigned to him by the Board of Directors or any committee of the Board designated by it so to act, or by the President or Chairman, if any.

SECTION 6.12 The Assistant Secretaries. At the request, or in absence or disability, of the Secretary, the Assistant Secretary, if any, designated by the Secretary or the Board of Directors shall perform all the duties of the Secretary and, when so acting, shall have all the powers of the Secretary. The Assistant Secretaries shall perform such other duties as from time to time may be assigned to them by the Board of Directors or any committee of the Board designated by it so to act, or by the President or Chairman, if any, or the Secretary.

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SECTION 6.13 Salaries. The salaries of the principal officers of the Corporation shall be fixed from time to time by the Board of Directors or a special committee thereof, and none of such officers shall be prevented from receiving a salary by reason of the fact that he is a director of the corporation.

ARTICLE 7

INDEMNIFICATION OF DIRECTORS AND OFFICERS

Each person who at any time is, or shall have been, a director or officer of the Corporation, and is threatened to be or is made a party to any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative by reason of the fact that he is, or was, a director, officer, employee or agent of the Corporation, or is or has served at the request of the Corporation as a director, officer, employee or agent of another corporation, partnership, joint venture, trust or other enterprise, shall be indemnified against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred by him in connection with any such action, suit or proceeding to the full extent permitted under subsections (a) through (e) of Section 145 of Title 8 of the Delaware Code, as from time to time amended. The foregoing right of indemnification shall in no way be exclusive of any other rights of indemnification to which such director, officer, employee or agent may be entitled, under any by-law, agreement, vote of shareholders or disinterested directors or otherwise, and shall continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of the heirs, executors and administrators of such a person.

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ARTICLE 8

CONTRACTS, CHECKS, DRAFTS, BANK ACCOUNTS, ETC.

SECTION 8.01 Execution of Contracts. Unless the Board of Directors shall otherwise determine, the President, the Chairman, if any, any Vice President, the Treasurer, the Secretary or any Assistant Secretary, may enter into any contract or execute any contract or other instrument, the execution of which is not otherwise specifically provided for, in the name and on behalf of the Corporation. The Board of Directors, or any committee designated thereby with power so to act, except as otherwise provided in these By-Laws, may authorize any other or additional officer or officers or agent or agents of the Corporation, and such authority may be general or confined to specific instances. Unless authorized so to do by these By-Laws or by the Board of Directors or by any such committee, no officer, agent or employee shall have any power or authority to bind the Corporation by any contract or engagement or to pledge its credit or to render it liable pecuniarily for any purpose or to any amount.

SECTION 8.02 Loans. No loan shall be contracted on behalf of the Corporation, and no evidence of indebtedness shall be issued, endorsed or accepted in its name, unless authorized by the Board of Directors or any committee of the Board designated by it so to act. Such authority may be general or confined to specific instances. When so authorized, the officer or officers thereunto authorized may effect loans and advances at any time for the Corporation from any bank, trust company or other institution, or from any firm, corporation or individual, and for such loans and advances may make, execute and deliver promissory notes or other evidences of indebtedness of the Corporation, and, when authorized as aforesaid, as security for the payment of any and all loans, advances, indebtedness and liabilities of the Corporation, may mortgage, pledge, hypothecate or transfer any real or personal property at any time owned or held by the Corporation, and to that end execute instruments of mortgage or pledge or otherwise transfer such property.

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SECTION 8.03 Checks, Drafts, etc. All checks, drafts, bills or exchange or other orders for the payment of money, obligations, notes, or other evidence of indebtedness, bills of lading, warehouse receipts and insurance certificates of the Corporation, shall be signed or endorsed by such officer or officers, agent or agents, attorney or attorneys, employee or employees, of the Corporation as shall from time to time be determined by resolution of the Board of Directors or any committee of the Board designated by it so to act.

SECTION 8.04 Deposits. All funds of the Corporation not otherwise employed shall be deposited from time to time to the credit of the Corporation in such banks, trust companies or other depositaries as the Board of Directors or any committee of the Board designated by it so to act may from time to time designate, or as may be designated by any officer or officers or agent or agents of the Corporation to whom such power may be delegated by the Board of Directors or any committee of the Board designated by it so to act and, for the purpose of such deposit and for the purposes of collection for the account of the Corporation may be endorsed, assigned and delivered by any officer, agent or employee of the Corporation or in such other manner as may from time to time be designated or determined by resolution of the Board of Directors or any committee of the Board designated by it so to act.

SECTION 8.05 Proxies in Respect of Securities of Other Corporations. Unless otherwise provided by resolution adopted by the Board of Directors or any committee of the Board designated by it to so act, the President or Chairman, if any, or any Vice President may from time to time appoint an attorney or attorneys or agent or agents of the Corporation, in the name and on behalf of the Corporation, to cast the votes which the Corporation may be entitled

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to cast as the holder of stock or other securities in any other corporation, association or trust any of whose stock or other securities may be held by the Corporation, at meetings of the holders of the stock or other securities of such other corporation, association or trust, or to consent in writing, in the name of the Corporation as such holder, to any action by such other corporation, association or trust, and may instruct the person or persons so appointed as to the manner of casting such votes or giving such consent, and may execute or cause to be executed in the name and on behalf of the Corporation and under its corporate seal, or otherwise, all such written proxies or other instruments as he may deem necessary or proper in the premises.

ARTICLE 9

BOOKS AND RECORDS

SECTION 9.01 Place. The books and records of the Corporation may be kept at such places within or without the State of Delaware as the Board of Directors may from time to time determine. The stock record books and the blank stock certificate books shall be kept by the Secretary or by any other officer or agent designated by the board of Directors.

SECTION 9.02 Addresses of Stockholders. Each stockholder shall furnish to the Secretary of the Corporation or to the transfer agent of the Corporation an address at which notices of meetings and all other corporate notices may be served upon or mailed to him, and if any stockholder shall fail to designate such address, corporate notices may be served upon him by mail, postage prepaid, to him at his post-office address last known to the Secretary or to the transfer agent of the Corporation or by transmitting a notice thereof to him at such address by facsimile, electronic mail or other available method.

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SECTION 9.03 Record Dates. The Board of Directors may fix in advance a date, not exceeding fifty days preceding the date of any meeting of stockholders, or the date for the payment of any dividend, or the date for the allotment of any rights, or the date when any change or conversion or exchange of capital stock of the Corporation shall go into effect, or a date in connection with obtaining such consent, as a record date for the determination of the stockholders entitled to notice of, and to vote at, any such meeting or any adjournment thereof, or entitled to receive payment of any such dividend, or to any such allotment of rights, or to exercise the rights in respect of any change, conversion or exchange or capital stock of the Corporation, or to give such consent, and in each such case such stockholders and only such stockholders as shall be stockholders of record on the date so fixed shall be entitled to notice of, or to vote at, such meeting and any adjournment thereof, or to receive payment of such dividend, or to receive such allotment of rights, or to exercise such rights or to give such consent, as the case may be, notwithstanding any transfer of any stock on the books of the Corporation after any such record date fixed as aforesaid.

ARTICLE 10

SHARES AND THEIR TRANSFER

SECTION 10.01 Certificates of Stock. Every owner of stock of the Corporation shall be entitled to have a certificate certifying the number of shares owned by him in the Corporation and designating the class of stock to which such shares belong, which shall otherwise be in such form as the Board of Directors shall prescribe. Every such certificate shall be signed by the Chief Executive Officer, President or Chairman, if any, or a Vice President, and by the Treasurer or any Assistant Treasurer or the Secretary or any Assistant Secretary of the Corporation; provided, however, that where such certificate is signed or countersigned by a transfer agent or registrar the signatures of such officers of the Corporation and the seal of the Corporation may be in facsimile form. In case any officer or officers who shall have signed, or whose facsimile signature or signatures shall have been used on, any such certificate or certificates shall cease to be such officer or officers of the Corporation, whether because of death, resignation or

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otherwise, before such certificate or certificates shall have been delivered by the Corporation, such certificate or certificates may nevertheless be issued and delivered by the Corporation as though the person or persons who signed such certificate or whose facsimile signature or signatures shall have been used thereof had not ceased to be such officer or officers of the Corporation.

SECTION 10.02 Record. A record shall be kept of the name of the person, firm or corporation owning the stock represented by each certificate for stock of the Corporation issued, the number of shares represented by each such certificate, and the date thereof, and, in case of cancellation, the date of cancellation. The person in whose name shares of stock stand on the books of the Corporation shall be deemed the owner thereof for all purposes as regards the Corporation.

SECTION 10.03 Transfer of Stock. Transfers of shares of the stock of the Corporation shall be made only on the books of the Corporation by the registered holder thereof, or by his attorney thereunto authorized, and on the surrender of the certificate or certificates for such shares properly endorsed.

SECTION 10.04 Transfer Agent and Registrar; Regulations. The Corporation shall, if and whenever the Board of Directors shall so determine, maintain one or more transfer offices or agencies, each in charge of a transfer agent designated by the Board of Directors, where the shares of the capital stock of the Corporation shall be directly transferable, and also if and whenever the Board of Directors shall so determine, maintain one or more registrar offices designated by the Board of Directors, where such shares of stock shall be registered. The Board of Directors may make such rules and regulations as it may deem expedient, not inconsistent with these By-Laws, concerning the issue, transfer and registration of certificates for shares of the capital stock of the Corporation.

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SECTION 10.05 Lost, Destroyed or Mutilated Certificates. In case of the alleged loss or destruction or the mutilation of a certificate representing capital stock of the Corporation, a new certificate may be issued in place thereof, in the manner and upon such terms as the Board of Directors may prescribe.

ARTICLE 11

SEAL

The Board of Directors shall provide a corporate seal, which shall be in the form of a circle and shall bear the name of the Corporation and the words and figures “Incorporated 2008, Delaware.”

ARTICLE 12

FISCAL YEAR

The fiscal year of the Corporation shall commence on the first day of November, except as otherwise provided from time to time by the Board of Directors.

ARTICLE 13

WAIVER OF NOTICE

Whenever any notice whatever is required to be given by statute, these By-Laws or the Certificate of Incorporation, a waiver thereof in writing, signed by the person or persons entitled to said notice, whether before or after the time stated therein, shall be deemed equivalent thereto.

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ARTICLE 14

AMENDMENTS

These By-Laws may be altered, amended or repealed, in whole or in part, and new By-Laws may be adopted, in whole or in part, by the affirmative vote of a majority of the whole Board of Directors given at a special Board of Directors meeting called and held for the purpose or by the affirmative vote of the holders of a majority of the issued and outstanding stock entitled to vote for the amendment of these By-Laws at a special meeting of the stockholders called and held for the purpose. Any such action by the Board of Directors may be changed by the affirmative vote of the holders of such a majority of the stockholders. No amendment may be made unless the By-Laws, as amended, are consistent with the requirements of law and of the Certificate of Incorporation.

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AMENDMENT NO. 1

TO

ASPEN AEROGELS, INC.

(f/k/a ASPEN MERGER SUB, INC.)

BY-LAWS

Section 3.02(a) of the By-Laws shall be amended by deleting the words “seven (7)” therein and by substituting “nine (9)” in lieu thereof.

Effective Date: July 21, 2009

Attested: ASPEN AEROGELS, INC.
By:	/s/ Christopher W. Nelson
	Christopher W. Nelson, Secretary

AMENDMENT NO. 2

TO

ASPEN AEROGELS, INC.

(f/k/a ASPEN MERGER SUB, INC.)

BY-LAWS

Section 3.02(a) of the By-Laws shall be amended by deleting the words “nine (9)” therein and by substituting “ten (10)” in lieu thereof.

Effective Date: January 18, 2011

Attested: ASPEN AEROGELS, INC.
By:	/s/ Christopher W. Nelson
	Christopher W. Nelson, Secretary

EX-4.2

Exhibit 4.2

THIS WARRANT AND ANY SECURITIES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), OR ANY APPLICABLE STATE SECURITIES LAWS. NEITHER THIS WARRANT, SUCH SECURITIES NOR ANY INTEREST THEREIN MAY BE TRANSFERRED EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE ACT AND APPLICABLE STATE SECURITIES LAWS.

THE SALE, ASSIGNMENT, HYPOTHECATION, PLEDGE, ENCUMBRANCE OR OTHER DISPOSITION AND VOTING OF ANY OF THE SHARES OF COMMON STOCK OF THE COMPANY ACQUIRED PURSUANT TO THE EXERCISE OF THIS WARRANT ARE RESTRICTED BY THE TERMS OF THE THIRD AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT, DATED AS OF JUNE 10, 2008, AMONG THE COMPANY AND CERTAIN OF ITS STOCKHOLDERS. THE COMPANY WILL NOT REGISTER THE TRANSFER OF SUCH SHARES OF COMMON STOCK ON THE BOOKS OF THE COMPANY UNLESS AND UNTIL THE TRANSFER HAS BEEN MADE IN COMPLIANCE WITH THE TERMS OF THE STOCKHOLDERS AGREEMENT, A COPY OF WHICH WILL BE PROVIDED AT NO COST TO THE HOLDER HEREOF UPON WRITTEN REQUEST TO THE COMPANY.

ASPEN AEROGELS, INC.

COMMON STOCK PURCHASE WARRANT

This document (this “Warrant”) certifies that, for good and valuable consideration, Aspen Aerogels, Inc., a Delaware corporation (the “Company”), grants to [IMPORT WARRANTHOLDER] (the “Warrantholder”), the right to subscribe for and purchase from the Company, on or before [IMPORT EXPIRATION TIME] (the “Expiration Time”), an aggregate of [IMPORT SHARE NUMBERS] validly issued, fully paid and nonassessable shares of Common Stock (the “Warrant Shares”), at the exercise price per share of $4.423 (the “Exercise Price”), all subject to the terms, provisions, conditions and adjustments (including adjustments to number of shares and Exercise Price) herein set forth. The Company acknowledges that the cash consideration paid by Warrantholder for this Warrant is $10.00 for income tax purposes, that such amount has been duly received by the Company, and that this Warrant is issued in connection with that certain financial accommodation entered into by and between Company as the obligor and Warrantholder as the obligee thereunder (the “Financing Arrangement”) and that this Warrant amends and restates all warrants previously issued to the Warrantholder in connection with the Financing Arrangement. Capitalized terms used herein which are not specifically defined in other sections of this Warrant, shall have the meanings set forth in Section 11.

1. Warrant Term. The purchase rights represented by this Warrant are exercisable, in whole or in part, at any time and from time to time, from and after the Warrant grant date of [IMPORT GRANT DATE], and on or prior to the earlier of the (i) Expiration Time, or (ii) in the event of a Corporate Event.

2. Exercise of Warrant; Payment of Taxes.

2.1 Exercise of Warrant. The purchase rights represented by this Warrant may be exercised by the Warrantholder, in whole or in part and from time to time, by the surrender of this Warrant (with a duly executed notice of exercise form, the “Exercise Form”, in the form attached hereto as Exhibit A) at the principal office of the Company and by the payment to the Company of an amount equal to the then applicable Exercise Price per share multiplied by the number of Shares then being purchased. If the Warrantholder is not already a party thereto, the Warrantholder shall also execute, upon request from the Company, a joinder agreement to the Stockholder’s Agreement, as amended and restated, such joinder agreement to be in form and substance mutually agreeable to both Warrantholder and Company. The Warrantholder shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the Shares represented thereby (and such Shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this Warrant is exercised.

2.2 Non-Cash Exercise.

(a) In lieu of payment in cash, the rights represented by this Warrant may also be exercised at any time by a written notice of exercise in the form of Exhibit A attached hereto, providing for the non-cash exercise of this Warrant for the Shares equal to the value (as determined below) of this Warrant (or the portion thereof being exercised), specifying that this non-cash exercise election has been made, and the net number of Shares to be issued after giving effect to such non-cash exercise. In the event the Warrantholder makes such election, Company shall issue to the holder a number of shares computed using the following formula:

X	=	Y(A-B)
		A

Where:

X = the number of Shares to be issued to the holder

Y = the number of Shares purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being exercised (as of the date of such non-cash exercise)

A = the Fair Market Value of one Share of Common Stock (as of the date of such non-cash exercise)

B = Exercise Price of one Share of Common Stock (as adjusted to the date of such non-cash exercise)

(b) For purposes of this Section 2.2, the “Fair Market Value” of one share of the Company’s Common Stock shall be equal to either (i) if the exercise of this Warrant occurs in connection with an initial public offering of the Company, then the Fair Market Value shall be equal to the “initial price to public” specified in the final prospectus with respect to the initial public offering, or (ii) if the exercise of this Warrant occurs after an initial public offering of the Company but not in connection therewith, then the Fair Market Value shall be equal to the average of the closing price(s) of the Company’s Common Stock as quoted over the counter or on any exchange on which the Common Stock is listed as such closing prices are published in The Wall Street Journal for the fifteen trading days (or such

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lesser number of trading days as the stock may have been actually trading) ending on the day prior to the date of determination of Fair Market Value. Notwithstanding the foregoing, if the Warrant is exercised in connection with a merger or sale of all or substantially all of the Company’s assets, Fair Market Value shall mean the value that would have been allocable to or received in respect of a Warrant Share had the Warrant been exercised prior to such merger or sale. If the Common Stock is not traded Over The Counter or on an exchange, or if the Warrant is not exercised in connection with a merger or sale of all or substantially all of its assets, then the Fair Market Value shall be determined in good faith by the Company’s board of directors. If the holder hereof does not agree with the determination of Fair Market Value as determined by the Company’s board of directors, the Company and the holder hereof shall negotiate an appropriate Fair Market Value. If after ten (10) days, the Company and the holder cannot agree, then the holder may request that the Fair Market Value be determined by an investment banker of national reputation selected by the Company and reasonably acceptable to the Warrantholder. The fees and expenses of such investment banker shall be borne by the Company unless the Fair Market Value determined by such investment banker is equal to or less that the Fair Market Value as determined by the Company, in which event the fees and expenses of such investment banker shall be borne by the holder hereof.

2.3 Automatic Exercise. Immediately before the expiration or termination of this Warrant, to the extent this Warrant is not previously exercised, and if the Fair Market Value of one share of the Company’s Common Stock subject to this Warrant is greater than the Exercise Price, then in effect as adjusted pursuant to this Warrant, this Warrant shall be deemed automatically exercised pursuant to Section 2.2 above, even if not surrendered. For purposes of such automatic exercise, the Fair Market Value of the Company’s Common Stock upon such expiration shall be determined pursuant to Section 2.2 (b) above. To the extent this Warrant or any portion thereof is deemed automatically exercised pursuant to this Section, the Company agrees to promptly notify the Warrantholder of the number of Shares, if any, the holder hereof is to receive by reason of such automatic exercise.

2.4 Exercise in Connection with an Initial Public Offering, Sale or Merger. Notwithstanding any other provision hereof, if the exercise of all or any portion of this Warrant is made or to be made in connection with the occurrence of a public offering, sale or merger of the Company, the exercise of all or any portion of this Warrant shall, at the election of the Warrantholder, be conditioned upon the consummation of the public offering, sale or merger of the Company in which case such exercise shall not be deemed to be effective until the consummation of such transaction. In the event that transaction is not consummated within 45 days of the targeted date of the transaction, any such exercise shall, at the election of the Warrantholder, be deemed rescinded.

2.5 Warrant Shares Certificate. A stock certificate for the Warrant Shares specified in the Exercise Form shall be delivered to the Warrantholder within five (5) Business Days after receipt of the Exercise Form by the Company and payment by the Warrantholder of the aggregate Exercise Price (or non-cash exercise in lieu of payment as permitted in Section 2.2), along with a check from the Company in lieu of any fractional shares which the Warrantholder would be entitled to purchase under this Warrant. If this Warrant was exercised in part, the Company shall, at the time of delivery of the stock certificate, deliver to the Warrantholder a new Warrant evidencing the right to purchase the remaining Warrant Shares, which new Warrant shall in all other respects be identical with this Warrant.

2.6 Payment of Taxes. The Company shall pay all expenses, taxes and other governmental charges with respect to the issue or delivery of the Warrant Shares, unless such tax or charge is imposed by law upon the Warrantholder.

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3. Restrictions on Transfer; Restrictive Legends.

3.1 Restrictions on Transfer. This Warrant and the Warrant Shares issuable upon exercise of all or part of this Warrant are unregistered securities that are subject to the restrictions on transfer imposed by the Securities Act and applicable state securities laws and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Securities Act and applicable state securities laws. The Warrant Shares issuable upon exercise of all or part of this Warrant are also subject to additional restrictions on transfer set forth in the Stockholders Agreement and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Stockholders Agreement.

3.2 Restrictive Legends. Until such time as the restrictions on transfer imposed on this Warrant by the Securities Act and applicable state securities laws shall no longer be effective, this Warrant, any Warrant issued to the Warrantholder upon the partial exercise of this Warrant pursuant to Section 2, and any Warrant issued to the Warrantholder in substitution for this Warrant pursuant to Section 7 shall be stamped or otherwise imprinted with a legend in substantially the form as set forth on the cover of this Warrant. Until such time as the restrictions on transfer imposed on the Warrant Shares by the Securities Act, applicable state securities laws and the Stockholders Agreement shall no longer be effective, each stock certificate for Warrant Shares and each stock certificate issued upon the direct or indirect transfer of any such Warrant Shares shall be stamped or otherwise imprinted with a legend in substantially the form provided in the Stockholders’ Agreement. Upon the termination of such restrictions on transfer, the Warrantholder may require the Company to issue a Warrant or a stock certificate for Warrant Shares, in each case without a legend, if and to the extent permitted by, and in accordance with, the Stockholders Agreement and applicable law.

4. Reservation and Registration of Shares. The Company covenants and agrees as follows:

4.1 Validly Issued and Free of Encumbrances. All Warrant Shares issued upon the exercise of all or any part of this Warrant shall, upon issuance and payment of the Exercise Price therefore (or upon non-cash exercise as permitted herein), be validly issued, fully paid and nonassessable, issued in compliance with all applicable federal and state securities laws, and free from all taxes, liens and charges with respect to the issue thereof, and not subject to any preemptive rights.

4.2 Sufficient Authorized Shares. During the period within which the rights represented by this Warrant may be exercised, the Company shall at all times have authorized and reserved, for the purpose of issuance of Common Stock upon any exercise of the purchase rights evidenced by this Warrant, and shall keep available free from preemptive rights, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

4.3 Noncontravention. The Company shall not, by amendment of its Certificate of Incorporation or through any reorganization, transfer of assets, spin-off, consolidation, merger, dissolution, issue or sale of securities or any other action or inaction, avoid or seek to avoid the observance or performance of any of the terms of this Warrant to be observed or performed hereunder, and shall at all times in good faith assist in performing, carrying out, and giving effect to the terms hereof and in the taking of all such actions as may be necessary or appropriate in order to protect the rights of the Warrantholder against dilution or other impairment.

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5. Anti-Dilution Adjustments. From and after the date hereof and until the Expiration Date, notwithstanding the fact that no Warrant Shares shall be issued and outstanding, the Exercise Price, and the number and type of Warrant Shares or other securities to be received upon exercise of the Warrant, shall be subject to adjustment as follows:

5.1 Dividend, Subdivision, Combination or Reclassification of Common Stock. If the Company shall, at any time or from time to time, prior to exercise in full of this Warrant: (a) pay a dividend or otherwise make a distribution on the outstanding shares of Common Stock payable in Capital Stock; (b) subdivide the outstanding shares of Common Stock into a larger number of shares; (c) combine the outstanding shares of Common Stock into a smaller number of shares; or (d) issue any shares of its Capital Stock in a reclassification of the Common Stock (other than any such event for which an adjustment is made pursuant to another clause of this Section 5), then, and in each such case, the Exercise Price and the number of Warrant Shares exercisable hereunder in effect immediately prior to such event shall be adjusted (and any other appropriate actions shall be taken by the Company) so that the Warrantholder shall thereafter be entitled to receive, upon the exercise of the unexercised portion of this Warrant, the number of shares of Common Stock or other securities of the Company that such Warrantholder would have owned or would have been entitled to receive upon or by reason of any of the events described above, had this Warrant been exercised immediately prior to the occurrence of such event. An adjustment made pursuant to this Section 5.1 shall become effective retroactively: (x) in the case of any such dividend or distribution, to a date immediately following the close of business on the record date for the determination of holders of Common Stock entitled to receive such dividend or distribution; or (y) in the case of any such subdivision, combination or reclassification, to the close of business on the day upon which such corporate action becomes effective.

5.2 Issuance of Common Stock or Common Stock Equivalents below Exercise Price. If the Company shall, at any time or from time to time, prior to exercise in full of this Warrant, issue or sell any shares of Common Stock or Common Stock Equivalents at a “New Issue Price” (as defined below) per share of Common Stock or Common Stock Equivalent that is less than the Exercise Price then in effect as of the record date or Issue Date referred to in the following sentence, as the case may be (the “Relevant Date”), other than issuances of Excluded Stock, then, and in each such case, the Exercise Price then in effect shall be adjusted by multiplying the Exercise Price in effect immediately prior to the Relevant Date by a fraction:

(a) the numerator of which shall be the sum of the number of shares of Common Stock outstanding on the Relevant Date (assuming conversion or exercise of all Common Stock Equivalents into Common Stock) plus (i) in the case of Common Stock, the number of shares of Common Stock which the aggregate consideration received by the Company for the total number of such additional shares of Common Stock so issued would purchase at the Exercise Price on the Relevant Date, or (ii) in the case of Common Stock Equivalents, the number of shares of Common Stock which the aggregate amount of the consideration paid for, or the aggregate exercise price of, such Common Stock Equivalents, plus any additional consideration payable upon conversion, exchange or exercise of such Common Stock Equivalents, would purchase at the Exercise Price on the Relevant Date; and

(b) the denominator of which shall be the sum of (i) the number of shares of Common Stock outstanding on the Relevant Date (assuming conversion or exercise of all Common Stock Equivalents into Common Stock) plus (ii) the number of additional shares of Common Stock issued or to be issued or, in the case of Common Stock Equivalents, the maximum number of shares of Common Stock into which such Common Stock Equivalents initially may convert, exchange or be exercised.

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Such adjustment shall be made whenever such shares of Common Stock or Common Stock Equivalents are issued, and shall become effective retroactively, in the case of an issuance to the stockholders of the Company, as such, to a date immediately following the close of business on the record date for the determination of stockholders entitled to receive such shares of Common Stock or Common Stock Equivalents, and, in all other cases, on the date of such issuance (the “Issue Date”); provided, however, that the determination as to whether an adjustment is required to be made pursuant to this Section 5.2 shall only be made upon the issuance of such shares of Common Stock or Common Stock Equivalents, and not upon the issuance of any security into which the Common Stock Equivalents convert, exchange or may be exercised. For purposes of this Section 5.2, the “New Issue Price” of any shares of Common Stock shall be equal to the price per share received by the Company upon the consummation of such sale and the “New Issue Price” of any Common Stock Equivalents shall be equal to (x) the sum of (A) the price for such Common Stock Equivalent plus (B) any additional consideration payable (without regard to any anti-dilution adjustments) upon the conversion, exchange or exercise of such Common Stock Equivalent, divided by (y) the number of shares of Common Stock initially underlying such Common Stock Equivalent.

5.3 Certain Distributions. If the Company shall, at any time or from time to time, prior to exercise in full of this Warrant, distribute to all holders of shares of the Common Stock (including any such distribution made in connection with a merger or consolidation in which the Company is the resulting or surviving Person and the Common Stock is not changed or exchanged) cash, evidences of indebtedness of the Company or another issuer, securities of the Company or another issuer or other assets or rights or warrants to subscribe for or purchase securities of the Company (excluding those distributions in respect of which an adjustment in the Exercise Price is made pursuant to another paragraph of this Section 5), then, and in each such case:

(a) the Exercise Price then in effect shall be adjusted (and any other appropriate actions shall be taken by the Company) by multiplying the Exercise Price in effect immediately prior to the date of such distribution by a fraction, (i) the numerator of which shall be the Current Market Price of the Common Stock immediately prior to the date of distribution less the then fair market value (as determined by the Board of Directors in the exercise of their fiduciary duties) of the portion of the cash, evidences of indebtedness, securities or other assets so distributed or of such rights or warrants applicable to one share of Common stock, and (ii) the denominator of which shall be the Current Market Price of the Common Stock immediately prior to the date of distribution (but such fraction shall not be greater than one); provided, however, that no adjustment shall be made upon such distribution pursuant to this Section 5.3(a) if an adjustment is made upon such distribution pursuant to Section 6; and

(b) the number of Warrant Shares for which this Warrant is exercisable immediately prior to such distribution shall be adjusted (and any other appropriate actions shall be taken by the Company) by multiplying the then-current number of Warrant Shares in effect immediately prior to the date of such distribution by a fraction, (i) the numerator of which shall be the Exercise Price in effect immediately prior to immediately prior to the date of distribution, and (ii) the denominator of which shall be the adjusted Exercise Price as determined pursuant to clause (a) of this Section 5.3 (but such fraction shall not be less than one); provided, however, that no adjustment shall be made upon such distribution pursuant to this Section 5.3(b) if an adjustment is made upon such distribution pursuant to Section 6.

Such adjustments shall be made whenever any such distribution is made and shall become effective retroactively to a date immediately following the close of business on the record date for the determination of stockholders entitled to receive such distribution.

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5.4 Other Changes. INTENTIONALLY DELETED

5.5 De Minimus Adjustments. Notwithstanding anything herein to the contrary, no adjustment under this Section 5 need be made to the Exercise Price and the number of Warrant Shares unless such adjustment would require an increase or decrease of at least one percent (1%) of the Exercise Price then in effect. Any lesser adjustment shall be carried forward and shall be made at the time of and together with the next subsequent adjustment which, together with any adjustment or adjustments so carried forward, shall amount to an increase or decrease of at least one percent (1%) of such Exercise Price. Any adjustment to the Exercise Price and the number of Warrant Shares carried forward and not theretofore made shall be made immediately prior to the exercise of this Warrant.

5.6 Notice of Adjustment under Section 5. The Company shall, no later than twenty (20) Business Days prior to the occurrence of any event that would result in an adjustment pursuant to this Section 5, provide the Warrantholder with a written notice describing such event in reasonable detail and setting forth the Exercise Price and number of Warrant Shares, as adjusted as a result of such event.

5.7 Reclassification, Reorganization, Change or Conversion. In case of any reclassification, reorganization, change or conversion of securities of the class issuable upon exercise of this Warrant (other than a change in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination), then in any of these events, the Company shall execute a replacement warrant (a “New Warrant”), in form and substance reasonably satisfactory to the holder of this Warrant, upon the exercise of which (and at a total purchase price under the New Warrant not to exceed that payable upon the exercise in full of this Warrant) the holder of the New Warrant shall receive, in lieu of each Share receivable upon the exercise of this Warrant, the same kind and amount of shares of stock, other securities, money and property receivable by a holder of one share of Common Stock upon such reclassification, reorganization, change or conversion. Such New Warrant shall provide for adjustments that shall be as nearly equivalent as may be practicable to the adjustments provided for in this Section 5. The provisions of this section 5.7 shall similarly apply to successive reclassifications, reorganizations, changes, or conversions.

Whenever the Exercise Price shall be adjusted pursuant to the provisions of this Warrant, the Company shall within ten (10) days of such adjustment deliver a certificate signed on behalf of the Company by its chief financial officer to the Warrantholder setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated, and the Exercise Price after giving effect to such adjustment.

6. Intentionally Deleted.

7. Exercise or Termination upon Corporate Event. The Company shall, no later than twenty (20) Business Days prior to the anticipated consummation date of any Corporate Event, provide the Warrantholder with a written notice describing such Corporate Event in reasonable detail and setting forth the consideration (i.e., securities, cash and other property) receivable for each share of Common Stock pursuant to such Corporate Event. If the aggregate Exercise Price, as of such consummation date, is equal to or greater than the aggregate value of the securities, cash and other property that would have been received in connection with Corporate Event by a holder of the number of shares of Common Stock for which this Warrant was exercisable immediately prior to such Corporate Event (the “Exercise Proceeds”), then this Warrant shall terminate upon the consummation of such Corporate Event. If the aggregate Exercise Price, as of such consummation date, is less than the aggregate value of the Exercise Proceeds, then the Warrantholder shall be entitled to exercise this Warrant in connection with such Corporate Event and shall automatically receive upon the consummation of such Corporate Event, in lieu of the Warrant Shares, the Exercise Proceeds.

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8. Loss or Destruction of Warrant. Subject to the terms and conditions hereof, upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, of such bond or indemnification as the Company may reasonably require, and, in the case of such mutilation, upon surrender and cancellation of this Warrant, the Company will execute and deliver to the Warrantholder a new Warrant of like tenor.

9. Ownership of Warrant. The Company may deem and treat the person in whose name this Warrant is registered as the holder and owner hereof (notwithstanding any notations of ownership or writing hereon made by anyone other than the Company) for all purposes and shall not be affected by any notice to the contrary, until presentation of this Warrant for registration of transfer.

10. Amendments. Any provision of this Warrant may be amended and the observance thereof waived only with the written consent of the Company and the Warrantholder.

11. Definitions. As used herein, unless the context otherwise requires, the following terms have the following respective meanings:

“Affiliate” means, (1) with respect to any Person, any of (a) a director, officer or stockholder holding 5% or more of the capital stock (on a fully diluted basis) of such Person, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling or descendant of any director or officer of such Person) and (c) any other Person that, directly or indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with, another Person or (2) in any event, any Person meeting the definition of “Affiliate” set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation, the possession, directly or indirectly, of the power to direct the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise.

“Board of Directors” means the Board of Directors of the Company.

“Business Day” means any day other than a Saturday, Sunday or a day on which national banks are authorized by law to close in the Commonwealth of Massachusetts.

“Capital Stock” means, with respect to any Person, any and all shares, interests, participation, rights in, or other equivalents (however designated and whether voting or non-voting) of, such Person’s capital stock and any and all rights, warrants or options exchangeable for or convertible into such capital stock (but excluding any debt security whether or not it is exchangeable for or convertible into such capital stock).

“Common Stock” means the Company’s presently authorized Common Stock, and any stock into or for which such Common Stock may hereafter be converted or exchanged pursuant to the Certificate of Incorporation of the Company as amended from time to time as provided by law and in such Certificate of Incorporation.

“Common Stock Equivalent” means any security or obligation which is by its terms convertible into shares of Common Stock or another Common Stock Equivalent, including, without limitation, any option, warrant or other subscription or purchase right with respect to Common Stock.

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“Corporate Event” means: (i) the sale, transfer, exchange or other disposition in one transaction or a series of related transactions of all or substantially all of the Company’s assets; (ii) any merger, consolidation or other corporate reorganization in one transaction or a series of related transactions that results in the stockholders of the Company immediately prior to such transaction holding less than fifty percent (50%) of the voting power of the surviving entity of such transaction; (iii) the dissolution or liquidation of the Company; or (iv) the sale, transfer, exchange or other disposition in one transaction or a series of related transactions of all or substantially all of the Company’s Common Stock, but does not include any one transaction or series of related transactions the sole purpose and effect of which is to change the state or type of organization of the Company (e.g., to change the Company from a Delaware corporation to a New York corporation or from a corporation to a limited liability company).

“Current Market Price” per share shall mean, as of the date of determination, (a) the average of the daily Market Price under clause (a), (b) or (c) of the definition thereof of the Common Stock during the immediately preceding thirty (30) trading days ending on such date, and (b) if the Common Stock is not then listed or admitted to trading on any national securities exchange or quoted in the over-the-counter market, then the Market Price under clause (d) of the definition thereof on such date.

“Exchange Act” means the Securities Exchange Act of 1934, as amended.

“Excluded Stock” has the meaning set forth in the Stockholders Agreement.

“Market Price” shall mean, as of the date of determination, (a) the closing price per share of Common Stock on such date published in The Wall Street Journal or, if no such closing price on such date is published in The Wall Street Journal, the average of the closing bid and asked prices on such date, as officially reported on the principal national securities exchange (including, without limitation, The Nasdaq Stock Market, Inc.) on which the Common Stock is then listed or admitted to trading; or (b) if the Common Stock is not then listed or admitted to trading on any national securities exchange but is designated as a national market system security by the National Association of Securities Dealers, Inc., the last trading price of the Common Stock on such date; or (c) if there shall have been no trading on such date or if the Common Stock is not so designated, the average of the reported closing bid and asked prices of the Common Stock on such date as shown by the National Market System of the National Association of Securities Dealers, Inc. Automated Quotations System and reported by any member firm of the New York Stock Exchange selected by the Company; or (d) if none of clauses (a), (b) or (c) is applicable, a market price per share determined at the Company’s expense by an appraiser chosen by the Warrantholder, or, if no such appraiser is so chosen more than ten (10) Business Days after notice of the necessity of such calculation shall have been delivered by the Company to the Warrantholder, then by an appraiser chosen by the Company and reasonably satisfactory to the Warrantholder. Any determination of the Market Price by an appraiser shall be based on a valuation of the Company as an entirety without regard to any discount for minority interests or disparate voting rights among classes of Capital Stock.

“Person” means any individual, firm, corporation, partnership, limited liability company, trust, incorporated or unincorporated association, joint venture, joint stock company, governmental authority or other entity of any kind, and shall include any successor (by merger or otherwise) of such entity.

“QPO” means an underwritten public offering (underwritten by a reputable underwriter of national reputation) of shares of Common Stock registered pursuant to the Securities Act.

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“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations of the United States Securities and Exchange Commission thereunder.

“Stockholders’ Agreement” means the Third Amended and Restated Stockholders’ Agreement, dated as of June 10, 2008, by and among the Company and each other stockholder of the Company party thereto, as amended from time to time.

12. Miscellaneous Provisions.

12.1 Entire Agreement. This Warrant constitutes the entire agreement between the Company and the Warrantholder with respect to this Warrant.

12.2 Binding Effect; Benefits. This Warrant shall inure to the benefit of and shall be binding upon the Company and the Warrantholder and their respective permitted successors and assigns. Nothing in this Warrant, expressed or implied, is intended to or shall confer on any person other than the Company and the Warrantholder, or their respective permitted successors or assigns, any rights, remedies, obligations or liabilities under or by reason of this Warrant.

12.3 Section and Other Headings. The section and other headings contained in this Warrant are for reference purposes only and shall not be deemed to be a part of this Warrant or to affect the meaning or interpretation of this Warrant.

12.4 Notices. All notices, demands and other communications provided for or permitted hereunder shall be made in writing and shall be by registered or certified first-class mail, return receipt requested, telecopier, courier service, overnight mail or personal delivery:

If to the Company:

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: Chief Executive Officer

with a copy (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 951-2207

Facsimile: (888) 325-9513

Attention: Christopher W. Nelson, Esq.

If to the Warrantholder:

[IMPORT WARRANTHOLDER ADDRESS INFORMATION]

All such notices and communications shall be deemed to have been duly given when delivered by hand, if personally delivered; when delivered by courier or overnight mail, if delivered by commercial courier service or overnight mail; five (5) Business Days after being deposited in the mail, postage prepaid, if mailed; and when receipt is mechanically acknowledged, if telecopied. Any party may, by notice given in accordance with this Section 12.4, designate another address or Person for receipt of notices hereunder.

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12.5 Issuance Tax, Attorneys’ Fees, Notices, Successors

(a) Issuance Tax. The issuance of certificates for shares of Common Stock upon exercise of this Warrant shall be made without charge to the holder hereof for any issuance tax in respect hereof, provided that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than that of the holder of this Warrant.

(b) Attorneys’ Fees. In the event of an action, suit or proceeding brought under or in connection herewith, the prevailing party therein shall be entitled to recover from, and the other party hereto agrees to pay, the prevailing party’s costs and expenses in connection therewith, including reasonably attorneys’ fees.

(c) Registration Agreement. The Warrantholder shall be entitled to all of the rights (excluding demand registration rights) set forth in that certain Third Amended and Restated Registration Rights Agreement (as the same may be amended from time to time) dated as of June 10, 2008 (the “Registration Rights Agreement”) among the Company and the parties thereto on the terms and conditions set forth therein, as if such terms and conditions were set forth in this Warrant. A copy of said Registration Rights Agreement has been provided to the Warrantholder. Simultaneously with the execution of this Warrant, the Warrantholder shall execute, at the option of the Company, either a counterpart signature page to such Registration Rights Agreement, or an amendment to the Registration Rights Agreement, either of which document shall add the Warrantholder as a party thereto and give the Warrantholder all registration and other rights (excluding demand registration rights) as and to the extent provided therein to “Investors” thereunder. Company and the Purchaser hereby further agree that for the purposes of the Registration Rights Agreement, the Shares issuable upon exercise of this Warrant are “Registrable Securities,” as that term is defined in the Registration Rights Agreement.

(d) Stockholders’ Agreement. The Warrantholder shall be entitled to all of the rights (excluding rights of first refusal) set forth in the Stockholders’ Agreement, as if such terms and conditions were set forth in this Warrant. A copy of said Stockholders’ Agreement has been provided to the Warrantholder. Simultaneously with the execution of this Warrant, the Warrantholder shall execute, at the option of the Company, either a counterpart signature page to such Stockholders’ Agreement, or an amendment to the Stockholders’ Agreement, either of which document shall add the Warrantholder as a party thereto and give the Warrantholder all rights and be subject to the obligations (excluding rights of first refusal) as and to the extent provided therein to “Investors” thereunder. Company and the Purchaser hereby further agree that for the purposes of the Stockholders’ Agreement, the Shares issuable upon exercise of this Warrant will be deemed to be Stock as that term is defined in the Stockholders’ Agreement.

12.6 Severability. Any term or provision of this Warrant which is invalid or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity or unenforceability without rendering invalid or unenforceable the terms and provisions of this Warrant or affecting the validity or enforceability of any of the terms or provisions of this Warrant in any other jurisdiction.

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12.7 GOVERNING LAW. ALL ISSUES CONCERNING THIS WARRANT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAW OF THE STATE OF DELAWARE, WITHOUT REGARD TO THE CONFLICTS OF LAW PRINCIPLES THEREOF.

12.8 Rights as Shareholders. No holder of this Warrant, as such, shall be entitled to vote or receive dividends or be deemed the holder of Common Stock or otherwise be entitled to any voting or other rights as a shareholder of the Company, until this Warrant shall have been exercised and the Shares purchasable upon the exercise shall have become deliverable, as provided herein.

13. Disposition of Warrant or Shares of Common Stock

With respect to any offer, sale or other transfer or disposition of this Warrant or any shares of Common Stock acquired pursuant to the exercise of this Warrant prior to registration of such shares, the holder hereof and each subsequent holder of this Warrant agrees to give written notice to the Company prior thereto, describing briefly the manner thereof, together with a written opinion of such holder’s counsel (if reasonably requested by the Company and reasonably satisfactory to the Company) to the effect that (i) such offer, sale or other transfer or disposition may be effected without registration or qualification of this Warrant or such shares of Common Stock under the Act as then in effect, and (ii) indicating whether or not under the Act this Warrant or the certificates representing such shares of Common Stock to be sold or otherwise transferred or disposed of require any restrictive legend thereon in order to ensure compliance with the Act; provided, however, that a written opinion of holder’s counsel shall not be required in connection with any sale pursuant to Rule 144. This Warrant or the certificates representing the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144) shall bear a legend as to the applicable restrictions on transferability in order to insure compliance with the Act, unless in the aforesaid opinion of counsel for the holder, such legend is not required in order to insure compliance with the Act. Upon any valid transfer of this Warrant or portion thereof, Company agrees to reissue the Warrant (or Warrants in the case of a partial transfer) and/or the Shares receivable upon the exercise hereof, and if the legend is not required, such re-issuance shall be without said legend. Nothing herein shall restrict the transfer of this Warrant (or any portion hereof) or the certificates representing the shares of Common Stock acquired pursuant to the exercise of this Warrant by the initial holder hereof or any successor holder to (i) any affiliate of such holder, including without limitation any partnership affiliated with such holder, any partner of any such partnership or any successor corporation to the holder hereof as a result of a merger or consolidation with or a sale of all or substantially all of the stock or assets of the holder, (ii) any Person in a public offering pursuant to an effective registration statement under the Act, (iii) to any other Person to the extent that the transfer to such Person is exempt from the registration requirements of the Act and such Person agrees in writing to be bound by all of the restrictions on transfer contained herein, or (iv) any Person or Persons if the holder hereof shall also transfer or assign all or part of its interest in the Financing Arrangement, and such Person agrees in writing to be bound by all of the restrictions on transfer contained herein provided, however, that no such transfer may be made to any direct competitor of the Company, which shall mean a Person engaged in the research, manufacture or sale of aerogels, aerogel based products or insulation products. Any transfer described above must be made in compliance with all applicable federal and state securities laws. The Company may issue stop transfer instructions to its transfer agent in connection with the foregoing restrictions.

14. Warrantholder’s Representations

The Warrantholder acknowledges that it has had access to all material information concerning the Company which it has requested. The Warrantholder also acknowledges that it has had the opportunity to, and has to its satisfaction, questioned the officers of the Company with respect to its

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investment hereunder. The Warrantholder represents that it understands that the Warrant and the Common Stock are speculative investments, that it is aware of the Company’s business affairs and financial condition and that it has acquired sufficient information about the Company to reach an informed and knowledgeable decision to acquire the Warrant. The Warrantholder is purchasing the Warrant and any Common Stock issued upon exercise thereof for investment for its own account only and not with a view to, or for resale in connection with, any “distribution” thereof in violation of the Act or applicable state securities laws. The Warrantholder further represents that it understands that the Warrant and Common Stock have not been registered under the Act or applicable state securities laws by reason of specific exemptions therefrom, which exemptions depend upon, among other things, the bona fide nature of the Warrantholder’s investment intent as expressed herein. The Warrantholder is an “accredited investor” as defined in Regulation D promulgated under the Act.

15. Company’s Representations.

As a material inducement to the Warrantholder to purchase this Warrant, the Company hereby represents and warrants that:

(a) The Company shall have made all filings under applicable federal and state securities laws necessary to consummate the issuance of this Warrant pursuant to this Agreement in compliance with such laws, except for such filings as may be made properly after the Grant Date.

(b) The copies of any existing stock purchase agreements and investor’s rights agreements and the Company’s charter documents and bylaws which have been furnished to Warrantholder or the Warrantholder’s counsel reflect all amendments made thereto at any time prior to the date hereof and are correct and complete.

(c) With respect to the issuance of this Warrant or the issuance of the Common Stock upon exercise of the Warrant, there are no statutory or contractual stockholders preemptive rights or rights of refusal, except for any such rights contained in any stock purchase agreement and/or investor’s rights agreements which have been waived. The Company has not violated any applicable federal or state securities laws in connection with the offer, sale or issuance of any of its capital stock, and the offer, sale and issuance of this Warrant does not require registration under the Act or any applicable state securities laws. To the best of the Company’s knowledge, there are no agreements between the Company’s stockholders with respect to the voting or transfer of the Company’s capital stock or with respect to any other aspect of the Company’s affairs.

(d) The execution, delivery and performance of this Warrant have been duly authorized by the Company. This Warrant constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Warrant, the issuance of the Common Stock upon exercise of the Warrant, and the fulfillment of and compliance with the respective terms hereof and thereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice or declaration to, or filing with, any court or administrative or governmental body or agency pursuant to, the charter or bylaws of the Company or any subsidiary, or any law, statute, rule or regulation to which the Company or any subsidiary is subject, or any agreement, instrument, order, judgment or decree to which the Company or any subsidiary is subject, except for any such filings required under applicable “blue sky” or state securities laws or required under Regulation D promulgated under the Act.

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16. Company Financial Information.

Until such time as the Company shall have satisfied all of its obligations under the Financing Arrangement, Company shall deliver to Warrantholder such financial information as is required under the terms of the Financing Arrangement. From and after the date that the Company shall have satisfied all of its obligations under the Financing Arrangement, and notwithstanding any other agreement to the contrary between the parties hereto, the Company shall deliver to the Warrantholder (so long as the Warrantholder holds all or any portion of the Warrant or any Preferred Stock or any shares of Common Stock issuable upon conversion of the Preferred Stock) all of the financial and other information delivered or required to be delivered by the Company to any of its stockholders, in their capacities as stockholders. All such financial and other information shall be delivered pursuant to this Section on a timely basis, but no later than 30 days after each fiscal quarter end for quarterly statements and no later than 120 days after each fiscal year end for annual statements.

*         *         *         *         *

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IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly authorized officer.

Issued By:	Accepted By:
ASPEN AEROGELS, INC.	[IMPORT WARRANTHOLDER]
By:
Donald R. Young	Name:
Chief Executive Officer	Title:

Dated: [IMPORT ISSUE DATE]

Exhibit A: Exercise Form

(To be executed upon exercise of this Warrant)

To: Aspen Aerogels, Inc. (“Company”) 30 Forbes Road, Northborough, MA 01532 Attention: Chief Financial Officer

[1. The undersigned hereby elects to purchase                     shares of Common Stock of Company pursuant to the terms of the attached Warrants, and tenders herewith payment of the purchase price of such shares in full.]

[1. The undersigned hereby elects to purchase                     shares of Common Stock of Company pursuant to a non-cash exercise of the Warrant as provided in Section 2 of the Warrant.]

2. Check here if applicable:                     The undersigned confirms that this exercise is made in connection with the occurrence of a public offering, sale or merger of the Company, and the undersigned further elects to condition this exercise of the Warrant upon the consummation of said public offering, sale or merger of the Company. This exercise shall not be deemed to be effective until the consummation of such transaction. In the event that transaction is not consummated within 45 days of the targeted date of the transaction, the undersigned will advise Company whether or not this exercise should be deemed rescinded.

2. Please issue a certificate or certificates representing said shares in the name of the undersigned or in such other name or names as are specified below:

[IMPORT WARRANTHOLDER ADDRESS INFORMATION]

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing such shares.

[IMPORT WARRANTHOLDER]
By:
	(Signature)
Its:
Date:

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EX-4.3

Exhibit 4.3

THIS WARRANT AND ANY SECURITIES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), OR ANY APPLICABLE STATE SECURITIES LAWS. NEITHER THIS WARRANT, SUCH SECURITIES NOR ANY INTEREST THEREIN MAY BE TRANSFERRED EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE ACT AND APPLICABLE STATE SECURITIES LAWS OR PURSUANT TO AN APPLICABLE EXEMPTION FROM THE REGISTRATION REQUIREMENTS OF THE ACT AND APPLICABLE STATE SECURITIES LAWS.

THE SALE, ASSIGNMENT, HYPOTHECATION, PLEDGE, ENCUMBRANCE OR OTHER DISPOSITION AND VOTING OF ANY OF THE SHARES OF COMMON STOCK OF THE COMPANY ACQUIRED PURSUANT TO THE EXERCISE OF THIS WARRANT ARE RESTRICTED BY THE TERMS OF THE THIRD AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT, DATED AS OF JUNE 10, 2008, AMONG THE COMPANY AND CERTAIN OF ITS STOCKHOLDERS. THE COMPANY WILL NOT REGISTER THE TRANSFER OF SUCH SHARES OF COMMON STOCK ON THE BOOKS OF THE COMPANY UNLESS AND UNTIL THE TRANSFER HAS BEEN MADE IN COMPLIANCE WITH THE TERMS OF THE STOCKHOLDERS AGREEMENT, A COPY OF WHICH WILL BE PROVIDED AT NO COST TO THE HOLDER HEREOF UPON WRITTEN REQUEST TO THE COMPANY.

ASPEN AEROGELS, INC.

COMMON STOCK PURCHASE WARRANT

This document (this “Warrant”) certifies that, for good and valuable consideration, Aspen Aerogels, Inc., a Delaware corporation (the “Company”), grants to [IMPORT WARRANTHOLDER], or any successor or permitted assign of such Person (the “Warrantholder”), the right to subscribe for and purchase from the Company, on or before the Expiration Time (as defined below), up to [IMPORT SHARE NUMBERS] validly issued, fully paid and nonassessable shares of Common Stock of the Company (as may be adjusted, the “Warrant Shares”) at the exercise price per share of $0.001 (the “Exercise Price”), all subject to the terms, provisions, conditions and adjustments (including adjustments to number of shares and Exercise Price) herein set forth. The Company acknowledges that the cash consideration paid by Warrantholder for this Warrant is $10.00 for income tax purposes, that such amount has been duly received by the Company, and that this Warrant is one of the Warrants issued in connection with that Note Purchase Agreement dated February 24, 2005 entered into by and between Company as the obligor and certain purchasers named therein (the “Financing Arrangement”) and that this Warrant amends and restates all warrants previously issued to the Warrantholder in connection with the Financing Agreement. Capitalized terms used herein which are not specifically defined in other sections of this Warrant, shall have the meanings set forth in Section 10.

1. Warrant Term. The purchase rights represented by this Warrant are exercisable, in whole or in part, at any time and from time to time, from and after the Warrant grant date and on or prior to the earlier of (i) [IMPORT EXPIRATION TIME] or (ii) the fourth (4^th) anniversary following the consummation of a QPO (such earlier date being the “Expiration Time”).

2. Exercise of Warrant; Payment of Taxes.

2.1 Exercise of Warrant. The purchase rights represented by this Warrant may be exercised by the Warrantholder, in whole or in part and from time to time, by the surrender of this Warrant (with a duly executed notice of exercise form, the “Exercise Form”, in the form attached hereto as Exhibit A) at the principal office of the Company and by the payment to the Company of an amount equal to the then applicable Exercise Price per share multiplied by the number of Warrant Shares then being purchased. If the Warrantholder is not already a party thereto, the Warrantholder shall also execute, upon request from the Company, a joinder agreement as an Investor to the Stockholders’ Agreement, as amended and restated, such joinder agreement to be in form and substance mutually agreeable to both the Warrantholder and the Company. The Warrantholder shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the Warrant Shares represented thereby (and such Warrant Shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this Warrant is exercised.

2.2 Net Exercise.

(a) In lieu of payment in cash, the rights represented by this Warrant may also be exercised at any time by a written notice of exercise in the form of Exhibit A attached hereto, providing for the net exercise of this Warrant for the Warrant Shares equal to the value (as determined below) of this Warrant (or the portion thereof being exercised), specifying that this net exercise election has been made, and the net number of Warrant Shares to be issued after giving effect to such net exercise. In the event the Warrantholder makes such election, Company shall issue to the Warrantholder a number of Warrant Shares computed using the following formula:

X	=	Y(A-B)
		A

Where:

X = the number of Warrant Shares to be issued to the Warrantholder

Y = the number of Warrant Shares purchasable under the Warrant or, if only a portion of the Warrant is being exercised, the portion of the Warrant being exercised (as of the date of such net exercise)

A = the Fair Market Value of one Share of Common Stock (as of the date of such net exercise)

B = Exercise Price of one Share of Common Stock (as adjusted to the date of such net exercise)

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(b) For purposes of this Section 2.2, the “Fair Market Value” of one share of the Company’s Common Stock shall be equal to either (i) if the exercise of this Warrant occurs in connection with an initial public offering of the Company, then the Fair Market Value shall be equal to the “initial price to public” specified in the final prospectus with respect to the initial public offering, or (ii) if the exercise of this Warrant occurs after an initial public offering of the Company but not in connection therewith, then the Fair Market Value shall be equal to the average of the closing price(s) of the Company’s Common Stock as quoted over the counter or on any exchange on which the Common Stock is listed as such closing prices are published in The Wall Street Journal for the fifteen (15) trading days (or such lesser number of trading days as the stock may have been actually trading) ending on the day prior to the date of determination of Fair Market Value. Notwithstanding the foregoing, if the Warrant is exercised in connection with a merger or sale of all or substantially all of the Company’s assets, Fair Market Value shall mean the value that would have been allocable to or received in respect of a Warrant Share had the Warrant been exercised prior to such merger or sale. If the Common Stock is not traded Over The Counter or on an exchange, or if the Warrant is not exercised in connection with a merger or sale of all or substantially all of its assets, then the Fair Market Value shall be reasonably determined in good faith by the Board of Directors. If the Warrantholder hereof does not agree with the determination of Fair Market Value as determined by the Board of Directors, the Company and the Warrantholder hereof shall negotiate an appropriate Fair Market Value. If after ten (10) days, the Company and the Warrantholder cannot agree, then the Warrantholder may request that the Fair Market Value be determined by an investment banker of national reputation selected by the Company and reasonably acceptable to the Warrantholder. The fees and expenses of such investment banker shall be borne by the Company unless the Fair Market Value determined by such investment banker is equal to or less than the Fair Market Value as determined by the Company, in which event the fees and expenses of such investment banker shall be borne by the Warrantholder hereof.

2.3 Automatic Exercise. Immediately before the expiration or termination of this Warrant, to the extent this Warrant is not previously exercised, and if the Fair Market Value of one share of the Company’s Common Stock subject to this Warrant is greater than the Exercise Price, then in effect as adjusted pursuant to this Warrant, this Warrant shall be deemed automatically exercised pursuant to Section 2.2 above, even if not surrendered. For purposes of such automatic exercise, the Fair Market Value of the Company’s Common Stock upon such expiration shall be determined pursuant to Section 2.2 (b) above. To the extent this Warrant or any portion thereof is deemed automatically exercised pursuant to this Section, the Company agrees to promptly notify the Warrantholder of the number of Warrant Shares, if any, the Warrantholder hereof is to receive by reason of such automatic exercise.

2.4 Exercise in Connection with an Initial Public Offering, Sale or Merger. Notwithstanding any other provision hereof, if the exercise of all or any portion of this Warrant is made or to be made in connection with the occurrence of a public offering, sale or merger of the Company, the exercise of all or any portion of this Warrant shall, at the election of the Warrantholder, be conditioned upon the consummation of the public offering, sale or merger of the Company in which case such exercise shall not be deemed to be effective until the consummation of such transaction. In the event that transaction is not consummated within forty-five (45) days of the targeted date of the transaction, any such exercise shall, at the election of the Warrantholder, be deemed rescinded.

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2.5 Warrant Shares Certificate. A stock certificate for the Warrant Shares specified in the Exercise Form shall be delivered to the Warrantholder within five (5) Business Days after receipt of the Exercise Form by the Company and payment by the Warrantholder of the aggregate Exercise Price (or net exercise in lieu of payment as permitted in Section 2.2), along with a check from the Company in lieu of any fractional shares which the Warrantholder would be entitled to purchase under this Warrant. If this Warrant was exercised in part, the Company shall, at the time of delivery of the stock certificate, deliver to the Warrantholder a new Warrant evidencing the right to purchase the remaining Warrant Shares, which new Warrant shall in all other respects be identical with this Warrant.

2.6 Payment of Taxes. The Company shall pay all expenses, taxes and other governmental charges with respect to the issue or delivery of the Warrant Shares, unless such tax or charge is imposed by law upon the Warrantholder.

3. Restrictions on Transfer; Restrictive Legends.

3.1 Restrictions on Transfer. This Warrant and the Warrant Shares issuable upon exercise of all or part of this Warrant are unregistered securities that are subject to the restrictions on transfer imposed by the Securities Act and applicable state securities laws and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Securities Act and applicable state securities laws. The Warrant Shares issuable upon exercise of all or part of this Warrant are also subject to additional restrictions on transfer set forth in the Stockholders’ Agreement and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Stockholders’ Agreement.

3.2 Restrictive Legends. Until such time as the restrictions on transfer imposed on this Warrant by the Securities Act and applicable state securities laws shall no longer be effective, this Warrant, any Warrant issued to the Warrantholder upon the partial exercise of this Warrant pursuant to Section 2 shall be stamped or otherwise imprinted with a legend in substantially the form as set forth on the cover of this Warrant. Until such time as the restrictions on transfer imposed on the Warrant Shares by the Securities Act, applicable state securities laws and the Stockholders’ Agreement shall no longer be effective, each stock certificate for Warrant Shares and each stock certificate issued upon the direct or indirect transfer of any such Warrant Shares shall be stamped or otherwise imprinted with a legend in substantially the form provided in the Stockholders’ Agreement. Upon the termination of such restrictions on transfer, the Warrantholder may require the Company to issue a Warrant or a stock certificate for Warrant Shares, in each case without a legend, if and to the extent permitted by, and in accordance with, the Stockholders’ Agreement and applicable law.

4. Reservation and Registration of Warrant Shares. The Company covenants and agrees as follows:

4.1 Validly Issued and Free of Encumbrances. All Warrant Shares issued upon the exercise of all or any part of this Warrant shall, upon issuance and payment of the Exercise Price therefore (or upon net exercise as permitted herein), be validly issued, fully paid and nonassessable, issued in compliance with all applicable federal and state securities laws, and free from all taxes, liens and charges with respect to the issue thereof, and not subject to any preemptive rights.

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4.2 Sufficient Authorized Shares. During the period within which the rights represented by this Warrant may be exercised, the Company shall at all times have authorized and reserved, for the purpose of issuance of Common Stock upon any exercise of the purchase rights evidenced by this Warrant, and shall keep available free from preemptive rights, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

4.3 Noncontravention. The Company shall not, by amendment of its Charter or through any reorganization, transfer of assets, spin-off, consolidation, merger, dissolution, issue or sale of securities or any other action or inaction, avoid or seek to avoid the observance or performance of any of the terms of this Warrant to be observed or performed hereunder, and shall at all times in good faith assist in performing, carrying out, and giving effect to the terms hereof and in the taking of all such actions as may be necessary or appropriate in order to protect the rights of the Warrantholder against dilution or other impairment.

5. Anti-Dilution Adjustments. From and after the date hereof and until the Expiration Date, notwithstanding the fact that no Warrant Shares shall be issued and outstanding, the Exercise Price, and the number and type of Warrant Shares or other securities to be received upon exercise of this Warrant, shall be subject to adjustment as follows:

5.1 Issuances of Common Stock Below Exercise Price.

(a) If the Company shall, at any time or from time to time after the Original Issuance Date, issue any shares of Common Stock (or be deemed to have issued shares of Common Stock as provided herein), other than Excluded Stock, without consideration or for a consideration per share less than the Exercise Price in effect immediately prior to the issuance of such Common Stock, then the Exercise Price, as in effect immediately prior to each such issuance, shall forthwith be lowered to:

(1) on or after the Operational Date, a price equal to the quotient obtained by dividing:

(A) an amount equal to the sum of (X) the total number of shares of Common Stock Deemed Outstanding immediately prior to such issuance, multiplied by the Exercise Price in effect immediately prior to such issuance, and (Y) the consideration received by the Company upon such issuance; by

(B) the total number of shares of Common Stock Deemed Outstanding immediately after the issuance of such Common Stock; or

(2) until the Operational Date, the lowest price per share at which any such shares of Common Stock have been issued or sold or deemed to have been issued or sold.

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(b) for the purposes of any adjustment of the Exercise Price pursuant to paragraph (a) above, the following provisions shall be applicable:

(1) In the case of the issuance of Common Stock for cash in a public offering or private placement, the consideration shall be deemed to be the amount of cash paid therefor after deducting therefrom any discounts, commissions or placement fees payable by the Company to any underwriter or placement agent in connection with the issuance and sale thereof.

(2) In the case of the issuance of Common Stock for a consideration in whole or in part other than cash, the consideration other than cash shall be deemed to be the fair value per share thereof, as reasonably determined in good faith by the Board, irrespective of any accounting treatment.

(3) In the case of the issuance of options to purchase or rights to subscribe for Common Stock, securities by their terms convertible into or exchangeable for Common Stock, or options to purchase or rights to subscribe for such convertible or exchangeable securities (except for options or rights to acquire or subscribe for Excluded Stock):

(A) the aggregate maximum number of shares of Common Stock deliverable upon exercise of such options to purchase or rights to subscribe for Common Stock shall be deemed to have been issued at the time such options or rights were issued and for a consideration equal to the consideration (determined in the manner provided in Sections 5.1(b)(1) and 5.1(b)(2) above), if any, received by the Company upon the issuance of such options or rights plus the minimum purchase price provided in such options or rights for the Common Stock covered thereby;

(B) the aggregate maximum number of shares of Common Stock deliverable upon conversion of or in exchange for any such convertible or exchangeable securities or upon the exercise of options to purchase or rights to subscribe for such convertible or exchangeable securities and subsequent conversion or exchange thereof shall be deemed to have been issued at the time such securities, options or rights were issued and for a consideration equal to the consideration received by the Company for any such securities and related options or rights (excluding any cash received on account of accrued interest or accrued dividends), plus the additional consideration, if any, to be received by the Company upon the conversion or exchange of such securities or the exercise of any related options or rights (the consideration in each case to be determined in the manner provided in Sections 5.1(b)(1) and 5.1(b)(2) above);

(C) on any change in the number of shares or exercise price of Common Stock deliverable upon exercise of any such options or rights or conversions of or exchanges for such securities, other than a change resulting from the antidilution provisions thereof, the Exercise Price shall forthwith be readjusted to the Exercise Price as would have been obtained had the adjustment made upon the issuance of such options, rights or securities not converted prior to such change or options or rights related to such securities not converted prior to such change been made upon the basis of such change; and

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(D) on the expiration of any such options or rights, the termination of any such rights to convert or exchange or the expiration of any options or rights related to such convertible or exchangeable securities, the Exercise Price shall forthwith be readjusted to the Exercise Price as would have been obtained had the adjustment made upon the issuance of such options, rights, securities or options or rights related to such securities been made upon the basis of the issuance of only the number of shares of Common Stock actually issued upon the exercise of such options or rights, upon the conversion or exchange of such securities, or upon the exercise of the options or rights related to such securities and subsequent conversion or exchange thereof.

(c) Whenever the Exercise Price is adjusted under this Section 5.1, the number of Warrant Shares issuable on exercise hereof shall be multiplied by a fraction the numerator of which is the Exercise Price immediately before such adjustment and the denominator is the Exercise Price as so adjusted.

5.2 Stock Dividends and Combinations.

(a) If, at any time after the Original Issuance Date, the number of shares of Common Stock outstanding is increased by a stock dividend payable in shares of Common Stock or by a subdivision or split-up of shares of Common Stock, then, following the record date for the determination of holders of Common Stock entitled to receive such stock dividend, subdivision or split-up, the Exercise Price shall be decreased and the number of shares of Common Stock issuable on exercise of this Warrant shall be increased in proportion to such increase in outstanding shares.

(b) If, at any time after the Original Issuance Date, the number of shares of Common Stock outstanding is decreased by a combination of the outstanding shares of Common Stock, then, following the record date for such combination, the Exercise Price shall be increased and the number of shares of Common Stock issuable on exercise of this Warrant shall be decreased in proportion to such decrease in outstanding shares.

5.3 Recapitalization, Etc. In the event of any capital reorganization of the Company, any reclassification of the stock of the Company (other than a change in par value or from par value to no par value or from no par value to par value or as a result of a stock dividend or subdivision, split-up or combination of shares), or any consolidation or merger of the Company, this Warrant shall after such reorganization, reclassification, consolidation or merger be exercisable for the kind and number of shares of stock or other securities or property of the Company or of the company resulting from such consolidation or surviving such merger to which the holder of the number of shares of Common Stock deliverable (immediately prior to the time of such reorganization, reclassification, consolidation or merger) upon exercise of this Warrant would have been entitled upon such reorganization, reclassification, consolidation or merger. The provisions of this clause shall similarly apply to successive reorganizations, reclassifications, consolidations and mergers.

5.4 De Minimis Adjustments. No adjustment in the Exercise Price shall be required unless such adjustment would require an increase or decrease of at least 0.1% in the Exercise Price; provided, however that any adjustments not required to be made by virtue of this sentence shall be carried forward and taken into account in any subsequent adjustment. All calculations under this Section 5 shall be made to the nearest one hundredth (1/100) of a cent or the nearest one tenth (1/10) of a share, as the case may be.

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5.5 Statement of Adjustments. Whenever the Exercise Price shall be adjusted as provided in this Section 5, the Company shall make available for inspection during regular business hours, at its principal executive offices or at such other place as may be designated by the Company, a statement, signed by its chief executive officer, showing in detail the facts requiring such adjustment and the Exercise Price that shall be in effect after such adjustment. The Company shall also cause a copy of such statement to be sent by first class certified mail, return receipt requested and postage prepaid, to the Warrantholder at such Warrantholder’s address appearing on the Company’s records. Where appropriate, such copy may be given in advance and may be included as part of any notice required to be mailed under the provisions of Section 5.6 below.

5.6 Notices. If the Company shall propose to take any action of the types described in Sections 5.2, 5.3, or 5.7 the Company shall give notice to each Warrantholder, which notice shall specify the record date, if any, with respect to any such action and the date on which such action is to take place. Such notice shall also set forth such facts with respect thereto as shall be reasonably necessary to indicate the effect of such action (to the extent such effect may be known at the date of such notice) on the Exercise Price and the number, kind or class of shares or other securities or property which shall be deliverable or purchasable upon the occurrence of such action or deliverable upon exercise of this Warrant. In the case of any action which would require the fixing of a record date, such notice shall be given at least twenty (20) days prior to the date so fixed, and in case of all other action, such notice shall be given at least thirty (30) days prior to the taking of such proposed action. Failure to give such notice, or any defect therein, shall not affect the legality or validity of any such action.

5.7 Dividends. Without duplication of any other adjustment provided for in this Section 5, at any time the Company makes or fixes a record date for the determination of holders of Common Stock entitled to receive a dividend or other distribution payable in property or securities of the Company other than shares of Common Stock, then, and in each such case,

(a) the Exercise Price then in effect shall be adjusted (and any other appropriate action shall be taken by the Company) by multiplying the Exercise Price in effect immediately prior to the date of such dividend or distribution by a fraction, (i) the numerator of which shall be the Fair Market Value (in all such cases under Section 5.7, as shall be determined pursuant to Section 2.2) of Common Stock immediately prior to the date of such dividend or distribution, less the Fair Market Value of the portion of the property or securities applicable to one share of Common Stock so dividended or distributed, and (ii) the denominator of which shall be the Fair Market Value of the Common Stock immediately prior to the date of such dividend or distribution (such fraction not to be greater than one); and

(b) the number of Warrant Shares for which this Warrant is exercisable immediately prior to such dividend or distribution shall be adjusted (and any other appropriate actions shall be taken by the Company) by multiplying the then-current number of Warrant Shares in effect immediately prior to the date of such dividend or distribution by a fraction, (i) the numerator of which shall be the Exercise Price in effect immediately prior to the date of such dividend or distribution, and (ii) the denominator of which shall be the adjusted Exercise Price as determined pursuant to Section 5.7(a) above (such fraction not to be less than one).

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Such adjustments shall be made whenever the Company makes or fixes a record date for the determination of holders of Common Stock entitled to receive a dividend or other distribution payable in property or securities of the Company (other than shares of Common Stock) and shall become effective retroactively to a date immediately following the close of business on the record date for the determination of stockholders entitled to receive such dividend or distribution.

5.8 Waiver. In the event that holders of at least sixty-six and two thirds percent (66 ²⁄₃%) of the Warrants, as the case may be, consent in writing to limit, or waive in its entirety, any antidilution adjustment to which the Warrantholders would otherwise be entitled hereunder, the Company shall not be required to make any adjustment whatsoever in excess of such limit or at all, as the terms of such consent may dictate.

5.9 Computations. The computations of all amounts under this Section 5 shall be made assuming all other antidilution or similar adjustments to be made to the terms of all other securities resulting from the transaction causing an adjustment pursuant to this Section 5 have previously been made so as to maintain the relative economic interest of the Warrants vis à vis all other securities issued by the Company.

5.10 Par Value. The Company shall take or cause to be taken such steps as shall be necessary to ensure that the par value per share of Common Stock is at all times less than or equal to the Exercise Price.

6. Transfer and Exchange. If this Warrant is presented to the Company with a request to register a transfer or to exchange it for an equal number of Warrants of other denominations the Company will do so.

7. Loss or Destruction of Warrant. Subject to the terms and conditions hereof, upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, of such bond or indemnification as the Company may reasonably require, and, in the case of such mutilation, upon surrender and cancellation of this Warrant, the Company will execute and deliver to the Warrantholder a new Warrant of like tenor.

8. Ownership of Warrant. The Company may deem and treat the Person in whose name this Warrant is registered as the Warrantholder and owner hereof (notwithstanding any notations of ownership or writing hereon made by anyone other than the Company) for all purposes and shall not be affected by any notice to the contrary, until presentation of this Warrant for registration of transfer.

9. Amendments. Any provision of this Warrant may be amended and the observance thereof waived only with the written consent of the Company and the Warrantholder.

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10. Definitions. As used herein, unless the context otherwise requires, the following terms have the following respective meanings:

“Affiliate” means, (1) with respect to any Person, any of (a) a director, officer or stockholder holding 5% or more of the capital stock (on a fully diluted basis) of such Person, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling or descendant of any director or officer of such Person) and (c) any other Person that, directly or indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with, another Person or (2) in any event, any Person meeting the definition of “Affiliate” set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation, the possession, directly or indirectly, of the power to direct the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise.

“Board of Directors” or “Board” means the Board of Directors of the Company.

“Business Day” means any day other than a Saturday, Sunday or a day on which national banks are authorized by law to close in the Commonwealth of Massachusetts.

“Charter” means the Amended and Restated Certificate of Incorporation of the Company, as amended from time to time.

“Common Stock” means the Company’s presently authorized Common Stock, and any stock into or for which such Common Stock may hereafter be converted or exchanged pursuant to the Charter of the Company as amended from time to time as provided by law and in such Charter.

“Common Stock Deemed Outstanding” means, at any given time, the sum of (i) the number of shares of Common Stock actually outstanding at such time, (ii) the number of shares of Common Stock issuable upon conversion of the Preferred Stock, and (iii) the number of shares of Common Stock issuable upon the exercise in full of all Convertible Securities whether or not the Convertible Securities are convertible into Common Stock at such time, but shall exclude any shares of Common Stock or Convertible Securities in the treasury of the Company or held for the account of the Company or any of its subsidiaries.

“Convertible Securities” means securities or obligations that are exercisable for, convertible into or exchangeable for shares of Common Stock. The term includes options, warrants or other rights to subscribe for or purchase Common Stock or to subscribe for or purchase other securities that are convertible into, directly or indirectly, or exchangeable for Common Stock.

“Excluded Stock” has the meaning set forth in the Stockholders Agreement.

“Operational Date” means the first date on which the Company’s operations for the production of the aerogel product meets each of the following criteria: (i) Quality — aerogel products meet the pre-established product specifications and are moved to inventory for sale; (ii) Quantity — one million square feet of aerogel product produced per calendar month for two consecutive months (based upon a 20 extractor plant and adjusted accordingly for any increase in plant capacity); and (iii) Variable costs — less than $.84 per square foot cast.

“Original Issuance Date” means the date and time that the first Warrant is issued by the Company.

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“Person” means any individual, firm, corporation, partnership, limited liability company, trust, incorporated or unincorporated association, joint venture, joint stock company, governmental authority or other entity of any kind, and shall include any successor (by merger or otherwise) of such entity.

“Preferred Stock” has the meaning set forth in the Charter.

“Purchase Agreement” means the Stock Purchase Agreement under which the Series D Convertible Preferred Stock were issued.

“QPO” means an underwritten public offering (underwritten by a reputable underwriter of national reputation) of shares of Common Stock registered pursuant to the Securities Act involving aggregate proceeds to the Company of at least $50,000,000 with an offering price per share of at least $6.36.

“Registration Rights Agreement” means the Third Amended and Restated Registration Rights Agreement, dated as of June 10, 2008, as amended, among the Company and certain parties thereto, as the same may be amended, modified or supplemented from time to time.

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations of the United States Securities and Exchange Commission thereunder.

“Stockholders’ Agreement” means the Third Amended and Restated Stockholders’ Agreement, dated as of June 10, 2008, by and among the Company and each other stockholder of the Company party thereto, as amended from time to time.

11. Miscellaneous Provisions.

11.1 Entire Agreement. This Warrant, the Financing Arrangement, the Stockholders’ Agreement, the Registration Rights Agreement and the Purchase Agreement constitute the entire agreement between the Company and the Warrantholder with respect to this Warrant.

11.2 Binding Effect; Benefits. This Warrant shall inure to the benefit of and shall be binding upon the Company and the Warrantholder and their respective permitted successors and assigns. Nothing in this Warrant, expressed or implied, is intended to or shall confer on any person other than the Company and the Warrantholder, or their respective permitted successors or assigns, any rights, remedies, obligations or liabilities under or by reason of this Warrant.

11.3 Section and Other Headings. The section and other headings contained in this Warrant are for reference purposes only and shall not be deemed to be a part of this Warrant or to affect the meaning or interpretation of this Warrant.

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11.4 Notices. All notices, demands and other communications provided for or permitted hereunder shall be made in writing and shall be by registered or certified first-class mail, return receipt requested, telecopier, courier service, overnight mail or personal delivery:

If to the Company:

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: Chief Executive Officer

with a copy (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 951-2207

Facsimile: (888) 325-9513

Attention: Christopher W. Nelson, Esq.

If to the Warrantholder:

to the addressees reflected on the Warrant

register maintained by the Company

All such notices and communications shall be deemed to have been duly given when delivered by hand, if personally delivered; when delivered by courier or overnight mail, if delivered by commercial courier service or overnight mail; five (5) Business Days after being deposited in the mail, postage prepaid, if mailed; and when receipt is mechanically acknowledged, if telecopied. Any party may, by notice given in accordance with this Section 11.4, designate another address or Person for receipt of notices hereunder.

11.5 Issuance Tax, Attorneys’ Fees, Notices, Successors

(a) Issuance Tax. The issuance of certificates for shares of Common Stock upon exercise of this Warrant shall be made without charge to the Warrantholder hereof for any issuance tax in respect hereof, provided that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than that of the Warrantholder.

(b) Attorneys’ Fees. In the event of an action, suit or proceeding brought under or in connection herewith, the prevailing party therein shall be entitled to recover from, and the other party hereto agrees to pay, the prevailing party’s costs and expenses in connection therewith, including reasonably attorneys’ fees.

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(c) Registration Agreement. The Warrantholder shall be entitled to all of the rights set forth in the Registration Rights Agreement, as if such terms and conditions were set forth in this Warrant. A copy of said Registration Rights Agreement has been provided to the Warrantholder. Simultaneously with the execution of this Warrant, the Warrantholder shall execute, at the option of the Company, either a counterpart signature page to such Registration Rights Agreement, or an amendment to the Registration Rights Agreement, either of which document shall add the Warrantholder as a party thereto and give the Warrantholder all registration and other rights (excluding demand registration rights) as and to the extent provided therein to “Investors” thereunder. The Company and the Warrantholder hereby further agree that for the purposes of the Registration Rights Agreement, the Warrant Shares are “Registrable Securities,” as that term is defined in the Registration Rights Agreement.

(d) Stockholders’ Agreement. The Warrantholder shall be entitled to all of the rights set forth in the Stockholders’ Agreement, as if such terms and conditions were set forth in this Warrant. A copy of said Stockholders’ Agreement has been provided to the Warrantholder. Simultaneously with the execution of this Warrant, the Warrantholder shall execute, at the option of the Company, either a counterpart signature page to such Stockholders’ Agreement, or an amendment to the Stockholders’ Agreement, either of which document shall add the Warrantholder as a party thereto and give the Warrantholder all rights and be subject to the obligations as and to the extent provided therein to “Investors” thereunder. Company and the Purchaser hereby further agree that for the purposes of the Stockholders’ Agreement, the Warrant Shares will be deemed to be Stock as that term is defined in the Stockholders’ Agreement.

11.6 Severability. Any term or provision of this Warrant which is invalid or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity or unenforceability without rendering invalid or unenforceable the terms and provisions of this Warrant or affecting the validity or enforceability of any of the terms or provisions of this Warrant in any other jurisdiction.

11.7 Governing Law. All issues concerning this Warrant shall be governed by and construed in accordance with the law of the State of Delaware, without regard to the conflicts of law principles thereof.

11.8 Rights as Shareholders. No Warrantholder, as such, shall be entitled to vote or receive dividends or be deemed the holder of Common Stock or otherwise be entitled to any voting or other rights as a shareholder of the Company, until this Warrant shall have been exercised and the Warrant Shares purchasable upon the exercise shall have become deliverable, as provided herein.

12. Disposition of Warrant or Shares of Common Stock. With respect to any offer, sale or other transfer or disposition of this Warrant or any Warrant Shares acquired pursuant to the exercise of this Warrant prior to registration of such shares, the Warrantholder hereof and each subsequent holder of this Warrant agrees to give written notice to the Company prior thereto, describing briefly the manner thereof, together with a written opinion of such holder’s counsel (if reasonably requested by the Company and reasonably satisfactory to the Company) to the effect that (i) such offer, sale or other transfer or disposition may be effected without registration or qualification of this Warrant or such shares of Common Stock under the Securities Act as then in effect, and (ii) indicating whether or not under the Securities Act this

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Warrant or the certificates representing such shares of Common Stock to be sold or otherwise transferred or disposed of require any restrictive legend thereon in order to ensure compliance with the Securities Act; provided, however, that a written opinion of holder’s counsel shall not be required in connection with any sale pursuant to Rule 144. This Warrant or the certificates representing the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144) shall bear a legend as to the applicable restrictions on transferability in order to insure compliance with the Securities Act, unless in the aforesaid opinion of counsel for the holder, such legend is not required in order to insure compliance with the Securities Act. Upon any valid transfer of this Warrant or portion thereof, Company agrees to reissue the Warrant (or Warrants in the case of a partial transfer) and/or the Warrant Shares receivable upon the exercise hereof, and if the legend is not required, such re-issuance shall be without said legend. Nothing herein shall restrict the transfer of this Warrant (or any portion hereof) or the certificates representing the Warrant Shares acquired pursuant to the exercise of this Warrant by the initial Warrantholder hereof or any successor holder to (i) any affiliate of such holder, including without limitation any partnership affiliated with such holder, any partner of any such partnership or any successor corporation to the holder hereof as a result of a merger or consolidation with or a sale of all or substantially all of the stock or assets of the holder, (ii) any Person in a public offering pursuant to an effective registration statement under the Securities Act, (iii) to any other Person to the extent that the transfer to such Person is exempt from the registration requirements of the Securities Act and such Person agrees in writing to be bound by all of the restrictions on transfer contained herein, or (iv) any Person or Persons if the holder hereof shall also transfer or assign all or part of its interest in the Financing Arrangement, and such Person agrees in writing to be bound by all of the restrictions on transfer contained herein provided, however, that no such transfer may be made to any direct competitor of the Company, which shall mean a Person engaged in the research, manufacture or sale of aerogels, aerogel based products or insulation products. Any transfer described above must be made in compliance with all applicable federal and state securities laws. The Company may issue stop transfer instructions to its transfer agent in connection with the foregoing restrictions.

13. Warrantholder’s Representations. The Warrantholder acknowledges that it has had access to all material information concerning the Company which it has requested. The Warrantholder also acknowledges that it has had the opportunity to, and has to its satisfaction, questioned the officers of the Company with respect to its investment hereunder. The Warrantholder represents that it understands that the Warrant and the Common Stock are speculative investments, that it is aware of the Company’s business affairs and financial condition and that it has acquired sufficient information about the Company to reach an informed and knowledgeable decision to acquire the Warrant. The Warrantholder is purchasing the Warrant and any Common Stock issued upon exercise thereof for investment for its own account only and not with a view to, or for resale in connection with, any “distribution” thereof in violation of the Securities Act or applicable state securities laws. The Warrantholder further represents that it understands that the Warrant and Common Stock have not been registered under the Securities Act or applicable state securities laws by reason of specific exemptions therefrom, which exemptions depend upon, among other things, the bona fide nature of the Warrantholder’s investment intent as expressed herein. The Warrantholder is an “accredited investor” as defined in Regulation D promulgated under the Securities Act.

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14. Company’s Representations. As a material inducement to the Warrantholder to purchase this Warrant, the Company hereby represents and warrants that:

(a) The Company has made all filings under applicable federal and state securities laws necessary to consummate the issuance of this Warrant pursuant to this Agreement in compliance with such laws, except for such filings as may be made properly after the date hereof.

(b) The copies of any existing stock purchase agreements and investor’s rights agreements and the Company’s charter documents and bylaws which have been furnished to Warrantholder or the Warrantholder’s counsel reflect all amendments made thereto at any time prior to the date hereof and are correct and complete.

(c) With respect to the issuance of this Warrant or the issuance of the Common Stock upon exercise of the Warrant, there are no statutory or contractual stockholders preemptive rights or rights of refusal, except for any such rights contained in any stock purchase agreement and/or investor’s rights agreements which have been waived. The Company has not violated any applicable federal or state securities laws in connection with the offer, sale or issuance of any of its capital stock, and the offer, sale and issuance of this Warrant does not require registration under the Securities Act or any applicable state securities laws. To the best of the Company’s knowledge, there are no agreements between the Company’s stockholders with respect to the voting or transfer of the Company’s capital stock or with respect to any other aspect of the Company’s affairs.

(d) The execution, delivery and performance of this Warrant have been duly authorized by the Company. This Warrant constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Warrant, the issuance of the Common Stock upon exercise of the Warrant, and the fulfillment of and compliance with the respective terms hereof and thereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice or declaration to, or filing with, any court or administrative or governmental body or agency pursuant to, the charter or bylaws of the Company or any subsidiary, or any law, statute, rule or regulation to which the Company or any subsidiary is subject, or any agreement, instrument, order, judgment or decree to which the Company or any subsidiary is subject, except for any such filings required under applicable “blue sky” or state securities laws or required under Regulation D promulgated under the Securities Act.

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15. Company Financial Information. Until such time as the Company shall have satisfied all of its obligations under the Financing Arrangement, Company shall deliver to Warrantholder such financial information as is required under the terms of the Financing Arrangement. From and after the date that the Company shall have satisfied all of its obligations under the Financing Arrangement, and notwithstanding any other agreement to the contrary between the parties hereto, the Company shall deliver to the Warrantholder (so long as the Warrantholder holds all or any portion of the Warrant or any Preferred Stock or any shares of Common Stock issuable upon conversion of the Preferred Stock) all of the financial and other information delivered or required to be delivered by the Company to any of its stockholders, in their capacities as stockholders.

*   *   *   *   *

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IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly authorized officer.

Issued By:	Accepted By:
ASPEN AEROGELS, INC.	[IMPORT WARRANTHOLDER]
By:
Donald R. Young	Name:
Chief Executive Officer	Title:
Dated:                     , 2005

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Exhibit A: Exercise Form

(To be executed upon exercise of this Warrant)

To:	Aspen Aerogels, Inc. (“Company”)
	30 Forbes Road, Northborough, MA 01532
	Attention: Chief Financial Officer

[1. The undersigned hereby elects to purchase                     shares of Common Stock of Company pursuant to the terms of the attached Warrants, and tenders herewith payment of the purchase price of such shares in full.]

[1. The undersigned hereby elects to purchase                     shares of Common Stock of Company pursuant to a net exercise of the Warrant as provided in Section 2 of the Warrant.]

2. Check here if applicable:             The undersigned confirms that this exercise is made in connection with the occurrence of a public offering, sale or merger of the Company, and the undersigned further elects to condition this exercise of the Warrant upon the consummation of said public offering, sale or merger of the Company. This exercise shall not be deemed to be effective until the consummation of such transaction. In the event that transaction is not consummated within 45 days of the targeted date of the transaction, the undersigned will advise Company whether or not this exercise should be deemed rescinded.

2. Please issue a certificate or certificates representing said shares in the name of the undersigned or in such other name or names as are specified below:

[name]

[address]

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing such shares.

[name]

By:
	(Signature)
Its:

Date:                         

EX-4.4

Exhibit 4.4

THIS WARRANT AND ANY SECURITIES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE BEEN ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER APPLICABLE U.S. OR NON-U.S. SECURITIES LAWS. NEITHER THIS WARRANT, SUCH SECURITIES NOR ANY INTEREST THEREIN MAY BE SOLD, TRANSFERRED, PLEDGED OR HYPOTHECATED EXCEPT IN ACCORDANCE WITH THE PROVISIONS OF REGULATION S OF THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), UNDER THE REGISTRATION PROVISIONS OF THE ACT OR PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE ACT. HEDGING TRANSACTIONS INVOLVING THIS WARRANT, SUCH SECURITIES NOR ANY INTEREST THEREIN MAY BE CONDUCTED UNLESS IN COMPLIANCE WITH THE ACT.

THE SALE, ASSIGNMENT, HYPOTHECATION, PLEDGE, ENCUMBRANCE OR OTHER DISPOSITION AND VOTING OF ANY OF THE SHARES OF CAPITAL STOCK OF THE COMPANY ACQUIRED PURSUANT TO THE EXERCISE OF THIS WARRANT ARE RESTRICTED BY THE TERMS OF THE THIRD AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT, DATED AS OF JUNE 10, 2008, AS AMENDED OR AMENDED AND RESTATED FROM TIME TO TIME, AMONG THE COMPANY AND CERTAIN OF ITS STOCKHOLDERS. THE COMPANY WILL NOT REGISTER THE TRANSFER OF SUCH SHARES OF CAPITAL STOCK ON THE BOOKS OF THE COMPANY UNLESS AND UNTIL THE TRANSFER HAS BEEN MADE IN COMPLIANCE WITH THE TERMS OF THE STOCKHOLDERS AGREEMENT, A COPY OF WHICH WILL BE PROVIDED AT NO COST TO THE HOLDER HEREOF UPON WRITTEN REQUEST TO THE COMPANY.

ASPEN AEROGELS, INC.

CAPITAL STOCK PURCHASE WARRANT

This document (this “Warrant”) dated as of June 10, 2008 certifies that, for good and valuable consideration, Aspen Aerogels, Inc., a Delaware corporation (the “Company”), grants to [IMPORT WARRANTHOLDER], or any successor or permitted assign of such Person (the “Warrantholder”), the right to subscribe for and purchase from the Company, on or before the Expiration Time (as defined below), up to [IMPORT SHARE NUMBERS] validly issued, fully paid and nonassessable shares of Common Stock of the Company (as may be adjusted, the “Warrant Shares”) at the exercise price per share of $0.001 (the “Exercise Price”). The Company acknowledges that the cash consideration paid by Warrantholder for this Warrant is $10.00, that such amount has been duly received by the Company, and that this Warrant is one of the Warrants issued in connection with that Amended and Restated Letter Agreement dated January 19, 2007, as amended and supplemented from time to time (as so amended and supplemented, the “Restated Letter Agreement”), entered into by and between Company as the borrower and certain lenders named therein, and that this Warrant amends, restates [and consolidates] all warrants previously issued to the Warrantholder in connection with the Restated Letter Agreement. Capitalized terms used herein which are not specifically defined in other sections of this Warrant, shall have the meanings set forth in Section 10.

1. Warrant Term. Subject to the provisions of Section 2.4, the purchase rights represented by this Warrant are exercisable, in whole or in part, at any time and from time to time, from and after the Warrant grant date and on or prior to June 10, 2016 (the “Expiration Time”).

2. Exercise of Warrant; Payment of Taxes.

2.1 Exercise of Warrant. The purchase rights represented by this Warrant may be exercised by the Warrantholder, in whole or in part and from time to time, by the surrender of this Warrant (with a duly executed notice of exercise form, the “Exercise Form”, in the form attached hereto as Exhibit A) at the principal office of the Company and by the payment to the Company of an amount equal to the then applicable Exercise Price per share multiplied by the number of Warrant Shares then being purchased. If the Warrantholder is not already a party thereto, the Warrantholder shall also execute, upon request from the Company, a joinder agreement as an Investor to the Stockholders’ Agreement, as amended and restated, such joinder agreement to be in form and substance mutually agreeable to both the Warrantholder and the Company. The Warrantholder shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the Warrant Shares represented thereby (and such Warrant Shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this Warrant is exercised.

2.2 Warrant Shares Certificate. A stock certificate for the Warrant Shares specified in the Exercise Form shall be delivered to the Warrantholder within five (5) Business Days after receipt of the Exercise Form by the Company and payment by the Warrantholder of the aggregate Exercise Price, along with a check from the Company in lieu of any fractional shares that the Warrantholder would be entitled to purchase under this Warrant. If this Warrant is exercised in part, the Company shall, at the time of delivery of the stock certificate, deliver to the Warrantholder a new Warrant evidencing the right to purchase the remaining Warrant Shares, which new Warrant shall in all other respects be identical to this Warrant.

2.3 Payment of Taxes. The Company shall pay all expenses, taxes and other governmental charges with respect to the issuance or delivery of the Warrant Shares, unless such expense, tax or charge is imposed by law upon the Warrantholder.

2.4 Exercise or Termination upon Corporate Event. If the aggregate Exercise Price, as of the consummation date of any Corporate Event, is equal to or greater than the aggregate value of the securities, cash and other property that would have been received in connection with a Corporate Event by a holder of the number of shares of Common Stock for which this Warrant was exercisable immediately prior to such Corporate Event (the “Exercise Proceeds”), then this Warrant shall automatically terminate upon the consummation of such Corporate Event. If the aggregate Exercise Price, as of such consummation date, is less than the aggregate value of the Exercise Proceeds, then the Warrantholder shall be entitled to exercise this Warrant in connection with such Corporate Event and shall automatically receive upon the consummation of such Corporate Event, in lieu of the Warrant Shares, the Exercise Proceeds, and this Warrant shall automatically terminate in connection therewith.

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3. Restrictions on Transfer; Restrictive Legends.

3.1 Restrictions on Transfer. This Warrant and the Warrant Shares issuable upon exercise of all or part of this Warrant are unregistered securities that are subject to the restrictions on transfer imposed by the Securities Act and applicable state securities laws and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Securities Act and applicable state securities laws. The Warrant Shares issuable upon exercise of all or part of this Warrant are also subject to additional restrictions on transfer set forth in the Stockholders’ Agreement and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Stockholders’ Agreement. As a condition to the exercise of this Warrant and the purchase of the Warrant Shares, the Warrantholder will become a party to the Stockholders’ Agreement pursuant to the form Joinder attached thereto.

3.2 Restrictive Legends. Until such time as the restrictions on transfer imposed on this Warrant by the Securities Act and applicable state securities laws shall no longer be effective, this Warrant, any Warrant issued to the Warrantholder upon the partial exercise of this Warrant pursuant to Section 2 shall be stamped or otherwise imprinted with a legend in substantially the form as set forth on the cover of this Warrant. Until such time as the restrictions on transfer imposed on the Warrant Shares by the Securities Act, applicable state securities laws and the Stockholders’ Agreement shall no longer be effective, each stock certificate for Warrant Shares and each stock certificate issued upon the direct or indirect transfer of any such Warrant Shares shall be stamped or otherwise imprinted with a legend in substantially the form provided in the Stockholders’ Agreement. Upon the termination of such restrictions on transfer, the Warrantholder may require the Company to issue a Warrant or a stock certificate for Warrant Shares, in each case without a legend, if and to the extent permitted by, and in accordance with, the Stockholders’ Agreement and applicable law.

3.3 Lock-Up. The Warrantholder agrees not to effect any sale or distribution of Warrant Shares during the seven (7) days prior to and the one hundred eighty (180) days after any Public Offering or such longer period as may be prescribed at such time. For purposes of this Warrant, “Public Offering” shall mean an underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, covering the offering and sale by the Company of Common Stock.

4. Reservation and Registration of Warrant Shares. The Company covenants and agrees as follows:

4.1 Validly Issued and Free of Encumbrances. All Warrant Shares issued upon the exercise of all or any part of this Warrant shall, upon issuance and payment of the Exercise Price therefore (or upon net exercise as permitted herein), be validly issued, fully paid and nonassessable, issued in compliance with all applicable federal and state securities laws, and free from all taxes, liens and charges with respect to the issue thereof, and not subject to any preemptive rights.

4.2 Sufficient Authorized Shares. During the period within which the rights represented by this Warrant may be exercised, the Company shall at all times have authorized and reserved, for the purpose of issuance of Common Stock upon any exercise of the purchase rights evidenced by this Warrant, and shall keep available free from preemptive rights, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

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4.3 Noncontravention. The Company shall not, by amendment of its Charter or through any reorganization, transfer of assets, spin-off, consolidation, merger, dissolution, issue or sale of securities or any other action or inaction, avoid or seek to avoid the observance or performance of any of the terms of this Warrant to be observed or performed hereunder, and shall at all times in good faith assist in performing, carrying out, and giving effect to the terms hereof and in the taking of all such actions as may be necessary or appropriate in order to protect the rights of the Warrantholder against dilution or other impairment.

5. Anti-Dilution Adjustments. From and after the date hereof and until the Expiration Date, notwithstanding the fact that no Warrant Shares shall be issued and outstanding, the Exercise Price, and the number and type of Warrant Shares or other securities to be received upon exercise of this Warrant, shall be subject to adjustment as follows:

5.1 Stock Dividends and Combinations.

(a) If, at any time after the date hereof, the number of shares of Common Stock outstanding is increased by a stock dividend payable in shares of Common Stock or by a subdivision or split-up of shares of Common Stock, then, following the record date for the determination of holders of Common Stock entitled to receive such stock dividend, subdivision or split-up, the Exercise Price shall be decreased and the number of shares of Common Stock issuable on exercise of this Warrant shall be increased in proportion to such increase in outstanding shares.

(b) If, at any time after the date hereof, the number of shares of Common Stock outstanding is decreased by a combination of the outstanding shares of Common Stock, then, following the record date for such combination, the Exercise Price shall be increased and the number of shares of Common Stock issuable on exercise of this Warrant shall be decreased in proportion to such decrease in outstanding shares.

5.2 Recapitalization, Etc. In the event of any capital reorganization of the Company, any reclassification of the stock of the Company (other than a change in par value or from par value to no par value or from no par value to par value or as a result of a stock dividend or subdivision, split-up or combination of shares), or any consolidation or merger of the Company, this Warrant shall after such reorganization, reclassification, consolidation or merger be exercisable for the kind and number of shares of stock or other securities or property of the Company or of the company resulting from such consolidation or surviving such merger to which the holder of the number of shares of Common Stock deliverable (immediately prior to the time of such reorganization, reclassification, consolidation or merger) upon exercise of this Warrant would have been entitled upon such reorganization, reclassification, consolidation or merger. The provisions of this clause shall similarly apply to successive reorganizations, reclassifications, consolidations and mergers.

5.3 Waiver. In the event that holders of at least sixty-six and two thirds percent (66 ²⁄₃%) of the Warrants, as the case may be, consent in writing to limit, or waive in its entirety, any antidilution adjustment to which the Warrantholders would otherwise be entitled hereunder, the Company shall not be required to make any adjustment whatsoever in excess of such limit or at all, as the terms of such consent may dictate.

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5.4 Computations. The computations of all amounts under this Section 5 shall be made assuming all other antidilution or similar adjustments to be made to the terms of all other securities resulting from the transaction causing an adjustment pursuant to this Section 5 have previously been made so as to maintain the relative economic interest of the Warrants vis à vis all other securities issued by the Company.

5.5 Par Value. The Company shall take or cause to be taken such steps as shall be necessary to ensure that the par value per share of Common Stock is at all times less than or equal to the Exercise Price.

6. Transfer and Exchange. If this Warrant is presented to the Company with a request to register a transfer or to exchange it for an equal number of Warrants of other denominations the Company will do so.

7. Loss or Destruction of Warrant. Subject to the terms and conditions hereof, upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, of such bond or indemnification as the Company may reasonably require, and, in the case of such mutilation, upon surrender and cancellation of this Warrant, the Company will execute and deliver to the Warrantholder a new Warrant of like tenor.

8. Ownership of Warrant. The Company may deem and treat the Person in whose name this Warrant is registered as the Warrantholder and owner hereof (notwithstanding any notations of ownership or writing hereon made by anyone other than the Company) for all purposes and shall not be affected by any notice to the contrary, until presentation of this Warrant for registration of transfer.

9. Amendments. Any provision of this Warrant may be amended and the observance thereof waived only with the written consent of the Company and the Warrantholder.

10. Definitions. As used herein, unless the context otherwise requires, the following terms have the following respective meanings:

“Affiliate” means, whether or not capitalized, (1) with respect to any Person, any of (a) a director, officer or stockholder holding five percent (5%) or more of the capital stock (on a fully diluted basis) of such Person, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling or descendant of any director or officer of such Person) and (c) any other Person that, directly or indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with, another Person or (2) in any event, any Person meeting the definition of “Affiliate” set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation, the possession, directly or indirectly, of the power to direct the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise.

“Business Day” means any day other than a Saturday, Sunday or a day on which national banks are authorized by law to close in the Commonwealth of Massachusetts.

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“Charter” means the Amended and Restated Certificate of Incorporation of the Company, as amended from time to time.

“Common Stock” means the Company’s presently authorized Common Stock, par value $.001 per share, and any stock into or for which such Common Stock may hereafter be converted or exchanged pursuant to the Charter of the Company as amended from time to time as provided by law and in such Charter.

“Corporate Event” means: (i) the sale, transfer, lease, license or other conveyance or disposition of all or substantially all of the Company’s assets; (ii) the Liquidation of the Company; or (iii) the sale, transfer or other disposition of all or substantially all of the Company’s capital stock to a Person or group of Persons that is not an Affiliate of the Company, but does not include any one transaction or series of related transactions the sole purpose and effect of which is to change the state or type of organization of the Company (e.g., to change the Company from a Delaware corporation to a New York corporation or from a corporation to a limited liability company).

“Liquidation” has the meaning defined in the Charter.

“Person” shall be construed broadly and shall include an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization, or a governmental entity (or any department, agency, or political subdivision thereof).

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations of the United States Securities and Exchange Commission thereunder.

“Stockholders’ Agreement” means the Third Amended and Restated Stockholders’ Agreement, dated as of the date hereof, as amended, among the Company and certain stockholders of the Company, as the same may be amended, modified or restated from time to time.

11. Miscellaneous Provisions.

11.1 Entire Agreement. This Warrant and the Stockholders’ Agreement constitute the entire agreement between the Company and the Warrantholder with respect to this Warrant.

11.2 Binding Effect; Benefits. This Warrant shall inure to the benefit of and shall be binding upon the Company and the Warrantholder and their respective permitted successors and assigns. Nothing in this Warrant, expressed or implied, is intended to or shall confer on any Person other than the Company and the Warrantholder, or their respective permitted successors or assigns, any rights, remedies, obligations or liabilities under or by reason of this Warrant.

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11.3 Section and Other Headings. The section and other headings contained in this Warrant are for reference purposes only and shall not be deemed to be a part of this Warrant or to affect the meaning or interpretation of this Warrant.

11.4 Notices. All notices, demands and other communications provided for or permitted hereunder shall be made in writing and shall be by registered or certified first-class mail, return receipt requested, telecopier, courier service, overnight mail or personal delivery:

If to the Company:

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: Chief Executive Officer

with a copy (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 951-2207

Facsimile: (888) 325-9513

Attention: Christopher W. Nelson, Esq.

If to the Warrantholder:

to the addressees reflected on the Warrant

register maintained by the Company

All such notices and other communications shall be deemed to have been given and received (i) in the case of personal delivery, on the date of such delivery, (ii) in the case of delivery by telecopy, on the date of such delivery, (iii) in the case of delivery by nationally recognized overnight courier, on the next business day following dispatch and (iv) in the case of mailing, on the third business day following such mailing.

11.5 Issuance Tax. The issuance of certificates for shares of Common Stock upon exercise of this Warrant shall be made without charge to the Warrantholder hereof for any issuance tax in respect hereof, provided that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than that of the Warrantholder.

11.6 Severability. Any term or provision of this Warrant which is invalid or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity or unenforceability without rendering invalid or unenforceable the terms and provisions of this Warrant or affecting the validity or enforceability of any of the terms or provisions of this Warrant in any other jurisdiction.

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11.7 Governing Law. All issues concerning this Warrant shall be governed by and construed in accordance with the law of the State of Delaware, without regard to the conflicts of law principles thereof.

11.8 Rights as Shareholders. The Warrantholder shall not be entitled to vote or receive dividends or be deemed the holder of Common Stock or otherwise be entitled to any voting or other rights as a shareholder of the Company, until this Warrant shall have been exercised and the Warrant Shares purchasable upon the exercise shall have become deliverable, as provided herein.

11.9 Counterparts. This Warrant may be executed in counterparts, each of which, when executed and delivered, shall be an original, but all counterparts shall be of and constitute one instrument.

12. Disposition of Warrant or Shares of Common Stock. With respect to any offer, sale or other transfer or disposition of this Warrant or any Warrant Shares acquired pursuant to the exercise of this Warrant prior to registration of such shares, the Warrantholder hereof and each subsequent holder of this Warrant agrees to give written notice to the Company prior thereto, describing briefly the manner thereof, together with a written opinion of such holder’s counsel (if reasonably requested by the Company and reasonably satisfactory to the Company) to the effect that (i) such offer, sale or other transfer or disposition may be effected without registration or qualification of this Warrant or such shares of Common Stock under the Securities Act as then in effect, and (ii) indicating whether or not under the Securities Act this Warrant or the certificates representing such shares of Common Stock to be sold or otherwise transferred or disposed of require any restrictive legend thereon in order to ensure compliance with the Securities Act; provided, however, that a written opinion of holder’s counsel shall not be required in connection with any sale pursuant to Rule 144. This Warrant or the certificates representing the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144) shall bear a legend as to the applicable restrictions on transferability in order to insure compliance with the Securities Act, unless in the aforesaid opinion of counsel for the holder, such legend is not required in order to insure compliance with the Securities Act. Upon any valid transfer of this Warrant or portion thereof, Company agrees to reissue the Warrant (or Warrants in the case of a partial transfer) and/or the Warrant Shares receivable upon the exercise hereof, and if the legend is not required, such re-issuance shall be without said legend. Nothing herein shall restrict the transfer of this Warrant (or any portion hereof) or the certificates representing the Warrant Shares acquired pursuant to the exercise of this Warrant by the initial Warrantholder hereof or any successor holder to (i) any affiliate of such holder, including without limitation any partnership affiliated with such holder, any partner of any such partnership or any successor corporation to the holder hereof as a result of a merger or consolidation with or a sale of all or substantially all of the stock or assets of the holder, (ii) any Person in a public offering pursuant to an effective registration statement under the Securities Act, or (iii) to any other Person to the extent that the transfer to such Person is exempt from the registration requirements of the Securities Act and such Person agrees in writing to be bound by all of the restrictions on transfer contained herein, provided, however, that no such transfer may be made to any direct competitor of the Company, which shall mean a Person engaged in the research, manufacture or sale of aerogels, aerogel based products or insulation products. Any transfer described above must be made in compliance with all applicable federal and state securities laws. The Company may issue stop transfer instructions to its transfer agent in connection with the foregoing restrictions.

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13. Warrantholder’s Representations. The Warrantholder acknowledges that it has had access to all material information concerning the Company which it has requested. The Warrantholder also acknowledges that it has had the opportunity to, and has to its satisfaction, questioned the officers of the Company with respect to its investment hereunder. The Warrantholder represents that it understands that the Warrant and the Common Stock are speculative investments, that it is aware of the Company’s business affairs and financial condition and that it has acquired sufficient information about the Company to reach an informed and knowledgeable decision to acquire the Warrant. The Warrantholder is purchasing the Warrant and any Common Stock issued upon exercise thereof for investment for its own account only and not with a view to, or for resale in connection with, any “distribution” thereof in violation of the Securities Act or applicable state securities laws. The Warrantholder further represents that it understands that the Warrant and Common Stock have not been registered under the Securities Act or applicable state securities laws by reason of specific exemptions therefrom, which exemptions depend upon, among other things, the bona fide nature of the Warrantholder’s investment intent as expressed herein. The Warrantholder is an “accredited investor” as defined in Regulation D promulgated under the Securities Act.

[Remainder of page intentionally left blank]

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IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly authorized officer.

Issued By:		Accepted By:
ASPEN AEROGELS, INC.		[IMPORT WARRANTHOLDER NAME]
By:		By:
	Donald R. Young	Name:
	Chief Executive Officer	Title:

Aspen Aerogels, Inc. Capital Stock Purchase Warrant

Exhibit A: Exercise Form

(To be executed upon exercise of this Warrant)

To:	Aspen Aerogels, Inc. (“Company”)
	30 Forbes Road, Northborough, MA 01532
	Attention: Chief Financial Officer

1. The undersigned hereby elects to purchase                         shares of Common Stock of Company pursuant to the terms of the attached Warrants, and tenders herewith payment of the purchase price of such shares in full.

2. Please issue a certificate or certificates representing said shares in the name of the undersigned or in such other name or names as are specified below:

[name]

[address]

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing such shares.

[name]

By:
	(Signature)
Its:

Date:                          

Aspen Aerogels, Inc. Capital Stock Purchase Warrant

EX-4.5

Exhibit 4.5

THIS WARRANT AND ANY SECURITIES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE BEEN ACQUIRED FOR INVESTMENT AND HAVE NOT BEEN REGISTERED UNDER APPLICABLE U.S. OR NON-U.S. SECURITIES LAWS. NEITHER THIS WARRANT, SUCH SECURITIES NOR ANY INTEREST THEREIN MAY BE SOLD, TRANSFERRED, PLEDGED OR HYPOTHECATED EXCEPT IN ACCORDANCE WITH THE PROVISIONS OF REGULATION S OF THE SECURITIES ACT, UNDER THE REGISTRATION PROVISIONS OF THE SECURITIES ACT OR PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE ACT. HEDGING TRANSACTIONS INVOLVING THIS WARRANT, SUCH SECURITIES OR ANY INTEREST THEREIN MAY NOT BE CONDUCTED UNLESS IN COMPLIANCE WITH THE SECURITIES ACT.

THE SALE, ASSIGNMENT, HYPOTHECATION, PLEDGE, ENCUMBRANCE OR OTHER DISPOSITION AND VOTING OF ANY OF THE SHARES OF CAPITAL STOCK OF THE COMPANY ACQUIRED PURSUANT TO THE EXERCISE OF THIS WARRANT ARE RESTRICTED BY THE TERMS OF THE THIRD AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT, DATED AS OF JUNE 10, 2008, AS AMENDED OR AMENDED AND RESTATED FROM TIME TO TIME, AMONG THE COMPANY AND CERTAIN OF ITS STOCKHOLDERS. THE COMPANY WILL NOT REGISTER THE TRANSFER OF SUCH SHARES OF CAPITAL STOCK ON THE BOOKS OF THE COMPANY UNLESS AND UNTIL THE TRANSFER HAS BEEN MADE IN COMPLIANCE WITH THE TERMS OF THE STOCKHOLDERS AGREEMENT, A COPY OF WHICH WILL BE PROVIDED AT NO COST TO THE HOLDER HEREOF UPON WRITTEN REQUEST TO THE COMPANY.

ASPEN AEROGELS, INC.

CAPITAL STOCK PURCHASE WARRANT

This document (this “Warrant”) dated as of June 10, 2008 certifies that, for good and valuable consideration, Aspen Aerogels, Inc., a Delaware corporation (the “Company”), grants to [                    ] or any successor or permitted assign of such Person (the “Warrantholder”), the right to subscribe for and purchase from the Company, on or before the Expiration Time (as defined below), up to [                    ] validly issued, fully paid and nonassessable shares of Common Stock of the Company (as may be adjusted, the “Warrant Shares”) at the exercise price per share of $0.001 (the “Exercise Price”). Capitalized terms used herein which are not specifically defined in other sections of this Warrant, shall have the meanings set forth in Section 10.

1. Warrant Term. Subject to the provisions of Section 2.4, the purchase rights represented by this Warrant are exercisable, in whole or in part, at any time and from time to time, from and after the Warrant grant date and on or prior to June 10, 2016 (the “Expiration Time”).

2. Exercise of Warrant; Payment of Taxes.

2.1 Exercise of Warrant. The purchase rights represented by this Warrant may be exercised by the Warrantholder, in whole or in part and from time to time, by the surrender of this Warrant (with a duly executed notice of exercise form, the “Exercise Form”, in the form attached hereto as Exhibit A) at the principal office of the Company and by the payment to the Company of an amount equal to the then applicable Exercise Price per share multiplied by the number of Warrant Shares then being purchased. The Warrantholder shall be deemed to have become the holder of record of, and shall be treated for all purposes as the record holder of, the Warrant Shares represented thereby (and such Warrant Shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this Warrant is exercised.

2.2 Warrant Shares Certificate. A stock certificate for the Warrant Shares specified in the Exercise Form shall be delivered to the Warrantholder within five (5) Business Days after receipt of the Exercise Form by the Company and payment by the Warrantholder of the aggregate Exercise Price, along with a check from the Company in lieu of any fractional shares that the Warrantholder would be entitled to purchase under this Warrant. If this Warrant is exercised in part, the Company shall, at the time of delivery of the stock certificate, deliver to the Warrantholder a new Warrant evidencing the right to purchase the remaining Warrant Shares, which new Warrant shall in all other respects be identical to this Warrant.

2.3 Payment of Taxes. The Company shall pay all expenses, taxes and other governmental charges with respect to the issuance or delivery of the Warrant Shares, unless such expense, tax or charge is imposed by law upon the Warrantholder.

2.4 Exercise or Termination upon Corporate Event. If the aggregate Exercise Price, as of the consummation date of any Corporate Event, is equal to or greater than the aggregate value of the securities, cash and other property that would have been received in connection with a Corporate Event by a holder of the number of shares of Common Stock for which this Warrant was exercisable immediately prior to such Corporate Event (the “Exercise Proceeds”), then this Warrant shall automatically terminate upon the consummation of such Corporate Event. If the aggregate Exercise Price, as of such consummation date, is less than the aggregate value of the Exercise Proceeds, then the Warrantholder shall be entitled to exercise this Warrant in connection with such Corporate Event and shall automatically receive upon the consummation of such Corporate Event, in lieu of the Warrant Shares, the Exercise Proceeds, and this Warrant shall automatically terminate in connection therewith.

3. Restrictions on Transfer; Restrictive Legends.

3.1 Restrictions on Transfer. This Warrant and the Warrant Shares issuable upon exercise of all or part of this Warrant are unregistered securities that are subject to the restrictions on transfer imposed by the Securities Act and applicable state securities laws and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Securities Act and applicable state securities laws. The Warrant Shares issuable upon exercise of all or part of this Warrant are also subject to additional restrictions on transfer set forth in the Stockholders’ Agreement and may not be offered, sold, transferred, pledged or otherwise disposed of, in whole or in part, to any Person other than in accordance with the Stockholders’ Agreement. As a condition to the exercise of this Warrant and the purchase of the Warrant Shares, the Warrantholder will become a party to the Stockholders’ Agreement pursuant to the form Joinder attached thereto.

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3.2 Restrictive Legends. Until such time as the restrictions on transfer imposed on this Warrant by the Securities Act and applicable state securities laws shall no longer be effective, this Warrant, any Warrant issued to the Warrantholder upon the partial exercise of this Warrant pursuant to Section 2 shall be stamped or otherwise imprinted with a legend in substantially the form as set forth on the cover of this Warrant. Until such time as the restrictions on transfer imposed on the Warrant Shares by the Securities Act, applicable state securities laws and the Stockholders’ Agreement shall no longer be effective, each stock certificate for Warrant Shares and each stock certificate issued upon the direct or indirect transfer of any such Warrant Shares shall be stamped or otherwise imprinted with a legend in substantially the form provided in the Stockholders’ Agreement. Upon the termination of such restrictions on transfer, the Warrantholder may require the Company to issue a Warrant or a stock certificate for Warrant Shares, in each case without a legend, if and to the extent permitted by, and in accordance with, the Stockholders’ Agreement and applicable law.

3.3 Lock-Up. The Warrantholder agrees not to effect any sale or distribution of Warrant Shares during the seven (7) days prior to and the one hundred eighty (180) days after any Public Offering or such longer period as may be prescribed at such time. For purposes of this Warrant, “Public Offering” shall mean an underwritten public offering pursuant to an effective registration statement under the Securities Act of 1933, as amended, covering the offering and sale by the Company of Common Stock.

4. Reservation and Registration of Warrant Shares. The Company covenants and agrees that during the period within which the rights represented by this Warrant may be exercised, the Company shall at all times have authorized and reserved, for the purpose of issuance of Common Stock upon any exercise of the purchase rights evidenced by this Warrant, and shall keep available free from preemptive rights, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

5. Anti-Dilution Adjustments. From and after the date hereof and until the Expiration Date, notwithstanding the fact that no Warrant Shares shall be issued and outstanding, the Exercise Price, and the number and type of Warrant Shares or other securities to be received upon exercise of this Warrant, shall be subject to adjustment as follows:

5.1 Stock Dividends and Combinations.

(a) If, at any time after the date hereof, the number of shares of Common Stock outstanding is increased by a stock dividend payable in shares of Common Stock or by a subdivision or split-up of shares of Common Stock, then, following the record date for the determination of holders of Common Stock entitled to receive such stock dividend, subdivision or split-up, the Exercise Price shall be decreased and the number of shares of Common Stock issuable on exercise of this Warrant shall be increased in proportion to such increase in outstanding shares.

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(b) If, at any time after the date hereof, the number of shares of Common Stock outstanding is decreased by a combination of the outstanding shares of Common Stock, then, following the record date for such combination, the Exercise Price shall be increased and the number of shares of Common Stock issuable on exercise of this Warrant shall be decreased in proportion to such decrease in outstanding shares.

5.2 Recapitalization, Etc. In the event of any capital reorganization of the Company, any reclassification of the stock of the Company (other than a change in par value or from par value to no par value or from no par value to par value or as a result of a stock dividend or subdivision, split-up or combination of shares), or any consolidation or merger of the Company, this Warrant shall after such reorganization, reclassification, consolidation or merger be exercisable for the kind and number of shares of stock or other securities or property of the Company or of the company resulting from such consolidation or surviving such merger to which the holder of the number of shares of Common Stock deliverable (immediately prior to the time of such reorganization, reclassification, consolidation or merger) upon exercise of this Warrant would have been entitled upon such reorganization, reclassification, consolidation or merger. The provisions of this clause shall similarly apply to successive reorganizations, reclassifications, consolidations and mergers.

5.3 Computations. The computations of all amounts under this Section 5 shall be made assuming all other antidilution or similar adjustments to be made to the terms of all other securities resulting from the transaction causing an adjustment pursuant to this Section 5 have previously been made so as to maintain the relative economic interest of the Warrants vis à vis all other securities issued by the Company.

5.4 Par Value. The Company shall take or cause to be taken such steps as shall be necessary to ensure that the par value per share of Common Stock is at all times less than or equal to the Exercise Price.

6. Transfer and Exchange. If this Warrant is presented to the Company with a request to register a transfer or to exchange it for an equal number of Warrants of other denominations the Company will do so.

7. Loss or Destruction of Warrant. Subject to the terms and conditions hereof, upon receipt by the Company of evidence reasonably satisfactory to it of the loss, theft, destruction or mutilation of this Warrant and, in the case of loss, theft or destruction, of such bond or indemnification as the Company may reasonably require, and, in the case of such mutilation, upon surrender and cancellation of this Warrant, the Company will execute and deliver to the Warrantholder a new Warrant of like tenor.

8. Ownership of Warrant. The Company may deem and treat the Person in whose name this Warrant is registered as the Warrantholder and owner hereof (notwithstanding any notations of ownership or writing hereon made by anyone other than the Company) for all purposes and shall not be affected by any notice to the contrary, until presentation of this Warrant for registration of transfer.

9. Amendments. Any provision of this Warrant may be amended and the observance thereof waived only with the written consent of the Company and the Warrantholder.

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10. Definitions. As used herein, unless the context otherwise requires, the following terms have the following respective meanings:

“Affiliate” means, (1) with respect to any Person, any of (a) a director, officer or stockholder holding 5% or more of the capital stock (on a fully diluted basis) of such Person, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling or descendant of any director or officer of such Person) and (c) any other Person that, directly or indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with, another Person or (2) in any event, any Person meeting the definition of “Affiliate” set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation, the possession, directly or indirectly, of the power to direct the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise.

“Business Day” means any day other than a Saturday, Sunday or a day on which national banks are authorized by law to close in the Commonwealth of Massachusetts.

“Charter” means the Amended and Restated Certificate of Incorporation of the Company, as amended from time to time.

“Common Stock” means the Company’s presently authorized Common Stock, par value $.001 per share, and any stock into or for which such Common Stock may hereafter be converted or exchanged pursuant to the Charter of the Company as amended from time to time as provided by law and in such Charter.

“Corporate Event” means: (i) the sale, transfer, lease, license or other conveyance or disposition of all or substantially all of the Company’s assets; (ii) the Liquidation of the Company; or (iii) the sale, transfer or other disposition of all or substantially all of the Company’s capital stock to a Person or group of Persons that is not an Affiliate of the Company, but does not include any one transaction or series of related transactions the sole purpose and effect of which is to change the state or type of organization of the Company (e.g., to change the Company from a Delaware corporation to a New York corporation or from a corporation to a limited liability company).

“Liquidation” has the meaning set forth in the Charter.

“Person” shall be construed broadly and shall include an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization, or a governmental entity (or any department, agency, or political subdivision thereof).

“Securities Act” means the Securities Act of 1933, as amended, and the rules and regulations of the United States Securities and Exchange Commission thereunder.

“Stockholders’ Agreement” means the Third Amended and Restated Stockholders’ Agreement, dated as of the date hereof, as amended, among the Company and certain stockholders of the Company, as the same may be amended, modified or restated from time to time.

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11. Miscellaneous Provisions.

11.1 Entire Agreement. This Warrant and the Stockholders’ Agreement constitute the entire agreement between the Company and the Warrantholder with respect to this Warrant.

11.2 Binding Effect; Benefits. This Warrant shall inure to the benefit of and shall be binding upon the Company and the Warrantholder and their respective permitted successors and assigns. Nothing in this Warrant, expressed or implied, is intended to or shall confer on any Person other than the Company and the Warrantholder, or their respective permitted successors or assigns, any rights, remedies, obligations or liabilities under or by reason of this Warrant.

11.3 Section and Other Headings. The section and other headings contained in this Warrant are for reference purposes only and shall not be deemed to be a part of this Warrant or to affect the meaning or interpretation of this Warrant.

11.4 Notices. All notices, demands and other communications provided for or permitted hereunder shall be made in writing and shall be by registered or certified first-class mail, return receipt requested, telecopier, courier service, overnight mail or personal delivery:

If to the Company:

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: Chief Executive Officer

with a copy (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 951-2207

Facsimile: (888) 325-9513

Attention: Christopher W. Nelson, Esq.

If to the Warrantholder:

to the addressees reflected on the Warrant

register maintained by the Company

All such notices and other communications shall be deemed to have been given and received (i) in the case of personal delivery, on the date of such delivery, (ii) in the case of delivery by telecopy, on the date of such delivery, (iii) in the case of delivery by nationally recognized overnight courier, on the next business day following dispatch and (iv) in the case of mailing, on the third business day following such mailing.

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11.5 Issuance Tax. The issuance of certificates for shares of Common Stock upon exercise of this Warrant shall be made without charge to the Warrantholder hereof for any issuance tax in respect hereof, provided that the Company shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any certificate in a name other than that of the Warrantholder.

11.6 Severability. Any term or provision of this Warrant which is invalid or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such invalidity or unenforceability without rendering invalid or unenforceable the terms and provisions of this Warrant or affecting the validity or enforceability of any of the terms or provisions of this Warrant in any other jurisdiction.

11.7 Governing Law. All issues concerning this Warrant shall be governed by and construed in accordance with the law of the State of Delaware, without regard to the conflicts of law principles thereof.

11.8 Rights as Shareholders. The Warrantholder shall not be entitled to vote or receive dividends or be deemed the holder of Common Stock or otherwise be entitled to any voting or other rights as a shareholder of the Company, until this Warrant shall have been exercised and the Warrant Shares purchasable upon the exercise shall have become deliverable, as provided herein.

12. Disposition of Warrant or Shares of Common Stock. With respect to any offer, sale or other transfer or disposition of this Warrant or any Warrant Shares acquired pursuant to the exercise of this Warrant prior to registration of such shares, the Warrantholder hereof and each subsequent holder of this Warrant agrees to give written notice to the Company prior thereto, describing briefly the manner thereof, together with a written opinion of such holder’s counsel (if reasonably requested by the Company and reasonably satisfactory to the Company) to the effect that (i) such offer, sale or other transfer or disposition may be effected without registration or qualification of this Warrant or such shares of Common Stock under the Securities Act as then in effect, and (ii) indicating whether or not under the Securities Act this Warrant or the certificates representing such shares of Common Stock to be sold or otherwise transferred or disposed of require any restrictive legend thereon in order to ensure compliance with the Securities Act; provided, however, that a written opinion of holder’s counsel shall not be required in connection with any sale pursuant to Rule 144. This Warrant or the certificates representing the shares of Common Stock thus transferred (except a transfer pursuant to Rule 144) shall bear a legend as to the applicable restrictions on transferability in order to insure compliance with the Securities Act, unless in the aforesaid opinion of counsel for the holder, such legend is not required in order to insure compliance with the Securities Act. Upon any valid transfer of this Warrant or portion thereof, Company agrees to reissue the Warrant (or Warrants in the case of a partial transfer) and/or the Warrant Shares receivable upon the exercise hereof, and if the legend is not required, such re-issuance shall be without said legend. Nothing herein shall restrict the transfer of this Warrant (or any portion hereof) or the certificates representing the Warrant Shares acquired pursuant to the exercise of this Warrant by the initial Warrantholder hereof or any successor holder to (i) any Affiliate of such holder, including without limitation any partnership Affiliated with such holder, any partner of any such partnership or any successor corporation to the holder hereof as a result of a merger or

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consolidation with or a sale of all or substantially all of the stock or assets of the holder, (ii) any Person in a public offering pursuant to an effective registration statement under the Securities Act, (iii) to any other Person to the extent that the transfer to such Person is exempt from the registration requirements of the Securities Act and such Person agrees in writing to be bound by all of the restrictions on transfer contained herein, provided, however, that no such transfer may be made to any direct competitor of the Company, which shall mean a Person engaged in the research, manufacture or sale of aerogels, aerogel based products or insulation products. Any transfer described above must be made in compliance with all applicable federal and state securities laws. The Company may issue stop transfer instructions to its transfer agent in connection with the foregoing restrictions.

13. Warrantholder’s Representations. The Warrantholder acknowledges that it has had access to all material information concerning the Company which it has requested. The Warrantholder also acknowledges that it has had the opportunity to, and has to its satisfaction, questioned the officers of the Company with respect to its investment hereunder. The Warrantholder represents that it understands that the Warrant and the Common Stock are speculative investments, that it is aware of the Company’s business affairs and financial condition and that it has acquired sufficient information about the Company to reach an informed and knowledgeable decision to acquire the Warrant. The Warrantholder is purchasing the Warrant and any Common Stock issued upon exercise thereof for investment for its own account only and not with a view to, or for resale in connection with, any “distribution” thereof in violation of the Securities Act or applicable state securities laws. The Warrantholder further represents that it understands that the Warrant and Common Stock have not been registered under the Securities Act or applicable state securities laws by reason of specific exemptions therefrom, which exemptions depend upon, among other things, the bona fide nature of the Warrantholder’s investment intent as expressed herein. The Warrantholder is an “accredited investor” as defined in Regulation D promulgated under the Securities Act.

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IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly authorized officer.

Issued By:		Accepted By:
ASPEN AEROGELS, INC.		[_____________________ ]
By:		By:
	John F. Fairbanks	Its:
	Chief Financial Officer

SIGNATURE PAGE TO ASPEN AEROGELS, INC.

COMMON STOCK PURCHASE WARRANT

Exhibit A: Exercise Form

(To be executed upon exercise of this Warrant)

To: Aspen Aerogels, Inc. (“Company”) 30 Forbes Road, Northborough, MA 01532

Attention: Chief Financial Officer

1. The undersigned hereby elects to purchase                                     shares of Common Stock of Company pursuant to the terms of the attached Warrants, and tenders herewith payment of the purchase price of such shares in full.

2. Please issue a certificate or certificates representing said shares in the name of the undersigned or in such other name or names as are specified below:

[name]

[address]

3. The undersigned represents that the aforesaid shares are being acquired for the account of the undersigned for investment and not with a view to, or for resale in connection with, the distribution thereof and that the undersigned has no present intention of distributing such shares.

[name]

	By:
		(Signature)
Date:	Its:

EX-4.6

Exhibit 4.6

THIS INSTRUMENT AND THE COMMON STOCK OF ASPEN AEROGELS, INC., A DELAWARE CORPORATION (THE “COMPANY”), ISSUABLE UPON EXERCISE OF THIS INSTRUMENT HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE STATE LAWS AND MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, OFFERED, PLEDGED OR OTHERWISE DISTRIBUTED FOR VALUE UNLESS THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND/OR SUCH LAWS COVERING THIS INSTRUMENT OR SUCH STOCK OR THE COMPANY, UPON ITS REQUEST, RECEIVES AN OPINION OF COUNSEL FOR THE HOLDER OF THIS INSTRUMENT OR SUCH STOCK STATING THAT SUCH SALE, TRANSFER, ASSIGNMENT, OFFER, PLEDGE OR OTHER DISTRIBUTION FOR VALUE IS EXEMPT FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACT AND APPLICABLE STATE LAWS.

THIS INSTRUMENT IS ALSO SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER AS PROVIDED IN THAT CERTAIN SUBORDINATED NOTE AND WARRANT PURCHASE AGREEMENT, DATED AS OF DECEMBER 29, 2010, BY AND AMONG THE COMPANY, THE PURCHASERS NAMED ON EXHIBIT A THERETO, AND PJC CAPITAL LLC, AS COLLATERAL AGENT, AS THE SAME MAY BE AMENDED, RESTATED OR MODIFIED FROM TIME TO TIME (THE “PURCHASE AGREEMENT”).

THIS WARRANT AND THE SECURITIES ISSUABLE UPON EXERCISE HEREOF ARE SUBJECT TO THE TERMS AND PROVISIONS OF THE PURCHASE AGREEMENT. A COPY OF THE PURCHASE AGREEMENT IS AVAILABLE AT THE EXECUTIVE OFFICES OF THE COMPANY.

[______] Shares of the Company Warrant No. __

WARRANT

To Subscribe for and Purchase Common Stock of

ASPEN AEROGELS, INC.

THIS CERTIFIES THAT, for value received, [                    ], a [                    ] (“Purchaser”) or registered permitted assigns (Purchaser and/or any Person (as defined in the Purchase Agreement referred to below) or Persons to whom Purchaser has assigned this Warrant herein called “Holder”), is entitled to subscribe for and purchase from Aspen Aerogels, Inc., a corporation organized and existing under the laws of the State of Delaware (the “Company”), at any time from and after the date hereof to and including December 29, 2017, subject to the early termination provisions of Section 4(d) below, [                    ] ([            ]) fully paid and nonassessable shares (subject to adjustment from time to time pursuant to the provisions below) of Common Stock at the price per share as specified below and to exercise the other rights, powers, and privileges provided for herein, all on the terms and subject to the conditions specified in this Warrant. Capitalized terms used herein and not defined shall have the meaning ascribed to them in the Subordinated Note and Warrant Purchase Agreement, dated as of December 29, 2010, by and among the Company and the Purchasers named therein (as such agreement may be supplemented, modified, amended or restated from time to time, the “Purchase Agreement”).

This Warrant is subject to the following provisions, terms and conditions:

1. Exercise and Payment of Purchase Price.

(a) The rights represented by this Warrant may be exercised by Holder at any time on or prior to the applicable termination or expiration date, in whole or in part, by delivery to the Company of a completed Subscription Form in the form attached hereto ten (10) days prior to the intended date of exercise and by the surrender of this Warrant (properly endorsed if required) at the principal office of the Company and upon payment to it of the Exercise Price as provided in paragraph 1(b) below. The Company agrees that the shares so purchased shall be and are deemed to be issued to Holder as the record owner of such shares as of the close of business on the date that is ten (10) days after the date on which this Warrant shall have been surrendered and payment made for such shares as aforesaid. Subject to the provisions of paragraph 2, certificates for the shares of Common Stock so purchased shall be delivered to Holder within a reasonable time, not exceeding ten (10) days, after the rights represented by this Warrant shall have been so exercised, and, unless this Warrant has expired or all of the rights to receive shares of Common Stock under this Warrant have been exercised, a new Warrant representing the number of shares of Common Stock with respect to which this Warrant shall not then have been exercised shall also be delivered to Holder within such time. The issuance of certificates for shares of Common Stock upon exercise of this Warrant shall be made without charge to the Holder for any issuance tax in respect thereof or other cost incurred by the Company in connection with such exercise and the related issuance of shares of Common Stock.

(b) The warrant purchase price (subject to adjustment as noted below) shall be $0.001 per share, payable by delivery of any of the following (1) a check payable to the Company in an amount equal to the product of the warrant purchase price per share multiplied by the number of shares of Common Stock being purchased upon such exercise (the “Exercise Price”), (2) the surrender to the Company of equity securities of the Company having a Fair Market Value equal to the Exercise Price of the Common Stock being purchased upon such exercise, (3) a written notice to the Company that Holder is exercising this Warrant (or a portion thereof) by reducing the outstanding principal balance of any debt instrument of the Company and/or any of its Subsidiaries held by Holder by an amount equal to the Exercise Price of the Common Stock being purchased upon such exercise, (4) a written notice to the Company that Holder is exercising this Warrant (or a portion thereof) by authorizing the Company to withhold from issuance a number of shares of Common Stock issuable upon such exercise of this Warrant which when multiplied by the Fair Market Value of such Common Stock is equal to the Exercise Price (and such withheld shares shall no longer be issuable under such Warrant) or (5) any combination of the foregoing.

(c) As a condition to the exercise of this Warrant, the Holder shall execute and deliver to the Company a Joinder Agreement whereby the Holder agrees to join as a “Stockholder” party and be bound by the terms and conditions of the Company’s Fifth Amended and Restated Stockholders’ Agreement dated as of September 22, 2010, as amended from time to time (the “Stockholders Agreement”). The foregoing shall be inapplicable in the event that the Stockholders Agreement has been terminated in accordance with the terms thereof, or if such Stockholders Agreement is amended to uniquely and adversely affect the rights of the Holders of the Warrants.

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2. Compliance with Transfer Restrictions. Notwithstanding the foregoing paragraph 1, the Company shall not be required to deliver any certificate for shares of Common Stock upon exercise of this Warrant except in accordance with the provisions, and subject to the limitations, of paragraph 7 hereof and the legends in paragraph 6 and on the first page hereof.

3. Covenants. The Company covenants and agrees as follows:

(a) All shares of Common Stock which may be issued upon the exercise of the rights represented by this Warrant will, upon issuance, be duly authorized and validly issued, fully paid and nonassessable.

(b) During the period within which the rights represented by this Warrant may be exercised, the Company will at all times have authorized, and reserved for the purpose of issue or transfer upon exercise of the subscription rights evidenced by this Warrant, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

(c) The Company shall not close its books against the transfer of this Warrant or of any shares of Common Stock issuable upon exercise of this Warrant in any manner which interferes with the timely exercise of this Warrant in accordance with the express terms hereof. The Company shall from time to time take all such action as may be necessary to assure that the par value per share of the Common Stock issuable upon exercise of this Warrant is at all times equal to or less than the warrant purchase price then in effect.

(d) The Company shall assist and cooperate with Holder in making any required governmental filings or obtaining any required governmental approvals prior to or in connection with any exercise of this Warrant (including, without limitation, making any filings required to be made by the Company).

(e) Notwithstanding any other provision hereof, if an exercise of any portion of this Warrant is to be made in connection with a registered public offering, the exercise of all or any portion of this Warrant may, at the election of Holder and upon written notice to the Company of such election, be conditioned upon the consummation of the public offering, in which case such exercise shall not be deemed to be effective unless and until the consummation of such transaction occurs, so long as such exercise occurs on or prior to the applicable termination or expiration date.

4. Adjustments to Warrant Purchase Price and Number of Shares. The above provisions are subject to the following:

(a) The warrant purchase price shall, from and after the date of issuance of this Warrant, be subject to adjustment from time to time as hereinafter provided. Upon each adjustment of the warrant purchase price, the holder of this Warrant shall thereafter be entitled to purchase, at the warrant purchase price resulting from such adjustment, the number of shares of Common Stock obtained by multiplying the warrant purchase price in effect immediately prior to such adjustment by the number of shares of Common Stock purchasable pursuant hereto immediately prior to such adjustment and dividing the product thereof by the warrant purchase price resulting from such adjustment.

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(b) If the Company declares or pays a dividend upon the Common Stock, then the following provisions shall apply:

(i) If such dividend is payable in Common Stock (other than a dividend declared to effect a subdivision of the outstanding shares of Common Stock, as described in paragraph (c) below), any Convertible Securities, or in any rights or options to purchase any Common Stock or Convertible Securities, then the Holder of this Warrant upon exercise hereof will be entitled to receive the number of shares of Common Stock, Convertible Securities, or other rights or options to purchase any Common Stock or Convertible Securities, as applicable, to which the Holder would be entitled upon such exercise, and in addition and without further payment therefor, such number of shares of Common Stock, Convertible Securities, or other rights or options to purchase any Common Stock or Convertible Securities, as applicable, such that upon exercise hereof, the Holder would receive such number of shares of Common Stock, Convertible Securities, or other rights or options to purchase any Common Stock or Convertible Securities, as applicable, as a result of each dividend described above.

(ii) If such dividend is payable otherwise than in cash out of earnings or earned surplus (determined in accordance with GAAP), except for a stock dividend payable in shares of Common Stock as provided above (a “Liquidating Dividend”), then the Company shall pay to the Holder of this Warrant at the time of payment thereof the Liquidating Dividend which would have been paid to such Holder on the Common Stock issuable upon exercise of this Warrant had the Warrants been fully exercised immediately prior to the date on which a record is taken for such Liquidating Dividend, or, if no record is taken, the date as of which the record holders of Common Stock entitled to such dividends are to be determined.

(ii) If such dividend is payable in cash out of earnings or earned surplus (determined in accordance with GAAP) (a “Dividend”), then (A) such Dividend shall be allocated proportionately to the holders of outstanding Common Stock and holders of all Warrants as though all Warrants (and, to the extent required by the terms thereof, any other warrants, options, Convertible Securities or other rights to acquire shares of Common Stock) had been fully exercised immediately prior to the date on which a record was taken for such Dividend, or, if no record was taken, the date as of which the record holders of Common Stock entitled to such dividends were determined, (B) the amount allocable to the Warrants shall be deposited by the Company in a separate interest-bearing account concurrently with the payment of such Dividend to the holders of Common Stock and (C) promptly after the exercise of this Warrant, the amount allocable to the Common Stock obtained by the Holder upon such exercise, plus all accrued interest thereon, shall be paid to the Holder.

(c) In case the Company shall at any time subdivide its outstanding shares of Common Stock into a greater number of shares, the warrant purchase price in effect immediately prior to such subdivision shall be proportionately reduced, and conversely, in case the outstanding shares of Common Stock of the Company shall be combined into a smaller number of shares, the warrant purchase price in effect immediately prior to such combination shall be proportionately increased.

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(d) If any capital reorganization or reclassification of the capital stock of the Company, or consolidation or merger of the Company with another corporation or other entity, or the sale of all or substantially all of its assets to another corporation or other entity shall be effected in such a way that holders of Common Stock shall be entitled to receive stock, securities or assets with respect to or in exchange for Common Stock, then, as a condition of such reorganization, reclassification, consolidation, merger or sale, lawful and adequate provision shall be made whereby the Holder shall thereafter have the right to purchase and receive, upon the basis and upon the terms and conditions specified in this Warrant (and in lieu of the shares of Common Stock purchasable upon the exercise of this Warrant), an amount of shares of stock, securities or assets as may be issued or payable with respect to or in exchange for such Common Stock that are equal to the number of shares of such stock immediately purchasable and receivable upon exercise of this Warrant had such reorganization, reclassification, consolidation, merger or sale not taken place. In any such case, appropriate provision shall be made with respect to the rights and interests of the Holder of this Warrant to the end that the provisions hereof (including without limitation provisions for adjustments of the warrant purchase price and of the number of shares of Common Stock purchasable upon the exercise of this Warrant) shall thereafter be applicable, as nearly as may be possible, in relation to any shares of stock, securities or assets thereafter deliverable upon the exercise hereof. The Company shall not effect any such consolidation, merger or sale, unless prior to the consummation thereof the successor corporation or other entity (if other than the Company) resulting from such consolidation or merger or the corporation or other entity purchasing such assets shall assume, by written instrument executed and mailed to the Holder of this Warrant at the last address of such Holder appearing on the books of the Company, the obligation to deliver to such Holder such shares of stock, securities or assets as, in accordance with the foregoing provisions, such Holder may be entitled to purchase. Notwithstanding anything to the contrary herein, if any consolidation or merger of the Company with another corporation or other entity, or the sale of all or substantially all of its assets to another corporation or other entity, shall be effected in such a way that all holders of Common Stock shall be entitled to receive shares of stock, securities, cash or assets with respect to or in exchange for Common Stock, then at its election the Company may provide the Holder of this Warrant with written notice of such proposed transaction, in reasonable detail, no less than ten (10) days prior to the consummation thereof, and, upon the Holder receiving an amount of shares of stock, securities, cash or assets that may be payable with respect to or in exchange for such Common Stock that is equal to the number of shares of such stock immediately purchasable and receivable upon the exercise of this Warrant had such consolidation, merger or sale not taken place less an amount of such consideration payable in the proposed transaction with a Fair Market Value equal to the aggregate Exercise Price, this Warrant shall terminate.

(e) Upon any adjustment of the warrant purchase price, then and in each such case the Company shall give written notice thereof, by first-class mail, postage prepaid, addressed to the Holder of this Warrant at the address of such Holder as shown on the books of the Company, which notice shall state the warrant purchase price resulting from such adjustment and the increase or decrease, if any, in the number of shares of Common Stock purchasable at such price upon the exercise of this Warrant, setting forth in reasonable detail the method of calculation and the facts upon which such calculation is based.

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(f) In case any time:

(i) the Company shall declare any cash dividend on its Common Stock;

(ii) the Company shall pay any dividend payable in stock upon its Common Stock or make any distribution (other than regular cash dividends) to the holders of its Common Stock;

(iii) the Company shall offer for subscription pro rata to the holders of its Common Stock any additional shares of stock of any class or other rights;

(iv) there shall be any capital reorganization, or reclassification of the capital stock of the Company, or consolidation or merger of the Company with, or sale of all or substantially all of its assets to, another corporation or other entity; or

(v) there shall be a voluntary or involuntary dissolution, liquidation or winding up of the Company;

then, in any one or more of said cases, the Company shall give written notice, by first-class mail, postage prepaid, addressed to the Holder of this Warrant at the address of such Holder as shown on the books of the Company, of the date on which (A) the books of the Company shall close or a record shall be taken for such dividend, distribution or subscription rights, or (B) such reorganization, reclassification, consolidation, merger, sale, dissolution, liquidation or winding up shall take place, as the case may be. Such notice shall also specify the date as of which the holders of Common Stock of record shall participate in such dividend, distribution or subscription rights, or shall be entitled to exchange their Common Stock for securities or other property deliverable upon such reorganization, reclassification, consolidation, merger, sale, dissolution, liquidation or winding up, as the case may be. Such written notice shall be given at least ten (10) days prior to the action in question and not less than ten (10) days prior to the record date or the date on which the Company’s transfer books are closed in respect thereto.

(g) If any event occurs as to which in the opinion of the Board of Directors of the Company the other provisions of this paragraph 4 are not strictly applicable or if strictly applicable would not fairly protect the purchase rights of the Holder of this Warrant or of Common Stock issuable upon exercise of this Warrant in accordance with the essential intent and principles of such provisions, then the Board of Directors shall make an adjustment in the application of such provisions, in accordance with such essential intent and principles, so as to protect such purchase rights as aforesaid.

(h) No fractional shares of Common Stock shall be issued upon the exercise of this Warrant, but, instead of any fraction of a share which would otherwise be issuable, the Company shall pay a cash adjustment (which may be effected as a reduction of the amount to be paid by the Holder hereof upon such exercise) in respect of such fraction in an amount equal to the same fraction of the Fair Market Value per share of Common Stock as of the close of business on the date of the notice of exercise required by paragraph 1 above.

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5. Voting Rights. This Warrant shall not entitle the Holder hereof to any voting rights or, except as expressly provided herein, other rights as a stockholder of the Company.

6. Limitations on Transfer.

(a) The Holder, by acceptance hereof, agrees that this Warrant shall not be transferable except to an Affiliate of the Holder or with the Company’s prior written consent (not to be unreasonably withheld.) In the event of a permitted transfer, the Holder agrees to give written notice to the Company before transferring this Warrant or any Warrant Stock and to comply with the legend at the top hereof (the “Legend”). Upon receipt by the Company of such notice and satisfaction of the requirements of the Legend, such Holder shall be entitled to transfer this Warrant, or to exercise this Warrant in accordance with its terms and dispose of the shares of Common Stock received upon such exercise or to dispose of shares of Common Stock received upon the previous exercise of the Warrant, all in accordance with the terms of hereof.

(b) All certificates representing shares of Common Stock issued upon exercise of this Warrant shall be endorsed with the following legend:

“THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE STATE LAWS AND MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, OFFERED, PLEDGED OR OTHERWISE DISTRIBUTED FOR VALUE UNLESS THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND/OR SUCH LAWS COVERING SUCH SECURITIES OR THE COMPANY, UPON ITS REQUEST, RECEIVES AN OPINION OF COUNSEL FOR THE HOLDER OF THIS CERTIFICATE STATING THAT SUCH SALE, TRANSFER, ASSIGNMENT, OFFER, PLEDGE OR OTHER DISTRIBUTION FOR VALUE IS EXEMPT FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACT AND APPLICABLE STATE LAWS.”

(c) The restrictions imposed by the Legend and by the legend referred to in paragraph 6(b) shall cease and terminate as provided in Section 9.19(F) of the Purchase Agreement.

7. Warrant Transferable. Subject to the provisions of Section 9.19 of the Purchase Agreement and paragraph 6 hereof, this Warrant and all rights hereunder are transferable, in whole or in part, at the principal office of the Company by the Holder hereof in person or by duly authorized attorney, upon surrender of this Warrant properly endorsed. Each Holder of this Warrant, by holding the same, consents and agrees that the registered holder of this Warrant may be treated by the Company and all other Persons dealing with this Warrant as the absolute owner thereof for any purpose and as the Person entitled to exercise the rights represented by this Warrant, or to the transfer thereof on the books of the Company, any notice to the contrary notwithstanding.

8. Registration Rights Agreement. Contemporaneously with the issuance to Purchaser of this Warrant, the Purchaser and the Company shall execute and deliver a joinder to, and be bound by and entitled to the benefits of, the Registration Rights Agreement.

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9. Exchange of Warrant. This Warrant is exchangeable, upon the surrender thereof at the principal office of the Company, for new Warrants of like tenor representing in the aggregate the right to subscribe for and purchase the number of shares of Common Stock which may be subscribed for and purchased hereunder, each of such new Warrants to represent the right to subscribe for and purchase such number of shares of Common Stock as shall be designated by the Holder hereof at the time of such surrender.

10. Replacement of Warrant. Upon receipt of evidence reasonably satisfactory to the Company (an affidavit of Holder shall be satisfactory) of the ownership and the loss, theft, destruction or mutilation of this Warrant, and in the case of any such loss, theft or destruction, upon receipt of indemnity reasonably satisfactory to the Company (provided that if Holder is a Purchaser or qualifies as an “accredited investor” under the Securities Act, its own agreement regarding indemnity shall be satisfactory), or, in the case of any such mutilation upon surrender of this Warrant, the Company shall (at its expense) execute and deliver, in lieu thereof, a new Warrant of like kind representing the same rights represented by such lost, stolen, destroyed or mutilated Warrant and dated the date of such lost, stolen, destroyed or mutilated Warrant.

11. Certain Definitions. The following terms have the respective meanings set forth below:

“Average Market Value” means the average of the Closing Price for the security in question for the thirty (30) trading days immediately preceding the date of determination.

“Closing Price” means

(a) If the primary market for the security in question is a securities exchange or other market or quotation system in which last sale transactions are reported on a contemporaneous basis, then the last reported sales price, regular way, of such security for such day, or, if there has not been a sale on such trading day, then the highest closing or last bid quotation therefor on such trading day (excluding, in any case, any price that is not the result of bona fide arm’s length trading); or

(b) If the primary market for such security is not a securities exchange or other market or quotation system in which last sale transactions are contemporaneously reported, then the highest closing or last bona fide bid or asked quotation by disinterested Persons in the over-the-counter market on such trading day as reported by such generally accepted source of publicly reported bid quotations as the Holder designates.

“Common Stock” shall mean and include the Company’s Common Stock, par value $.001 per share, and shall also include, in the case of any reclassification of the outstanding shares thereof, the stock, securities or assets provided for in paragraph 4(d) above.

“Convertible Securities” means obligations or any shares of stock of the Company which are convertible into or exchangeable for Common Stock.

“Exchange Act” means the Securities Exchange Act of 1934, as the same may be amended from time to time.

“Exercise Price” shall have the meaning ascribed thereto in paragraph 1(b).

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“Fair Market Value” means:

(a) As to securities regularly traded in the organized securities markets, the Average Market Value; and

(b) As to all securities not regularly traded in the securities markets and all other property, the fair market value of such securities or property as determined in good faith by the Board of Directors of the Company at the time the rights represented by this Warrant have been exercised in accordance herewith or at the time such Board authorizes the transaction requiring a determination of Fair Market Value under this Warrant, as the case may be.

“Securities Act” means the Securities Act of 1933, as the same may be amended from time to time.

12. Choice of Law. All questions concerning this Warrant will be governed by and construed in accordance with the internal laws of the State of New York, without reference to principles of conflicts of law other than Sections 5-1401 and 5-1402 of the New York General Obligations Law.

13. Headings. Section and subsection headings are included herein for convenience of reference only and shall not constitute a part of this Warrant for any other purposes or be given substantive effect.

14. Severability. The invalidity, illegality, or unenforceability in any jurisdiction of any provision under this Warrant shall not affect or impair the remaining provisions of this Warrant or render any such provision invalid, illegal or unenforceable in any other jurisdiction.

[Remainder of Page Intentionally Left Blank]

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IN WITNESS WHEREOF, the Company has caused this Warrant to be signed by its duly authorized officer and this Warrant to be dated as of             .

ASPEN AEROGELS, INC.

By:                                                                                                         

Name:                                                                                                   

Title:                                                                                                     

[Signature Page to Warrant for [            ] Shares]

FORM OF ASSIGNMENT

(To Be Signed Only Upon Assignment)

FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers unto             this Warrant, and appoints             to transfer this Warrant on the books of Aspen Aerogels, Inc. with the full power of substitution in the premises.

Dated:

In the presence of:

(Signature must conform in all respects to the name of the holder as specified on the face of this Warrant without alteration, enlargement or any change whatsoever, and the signature must be guaranteed in the usual manner)

SUBSCRIPTION FORM

To be Executed by the Holder of this Warrant if such Holder

Desires to Exercise this Warrant in Whole or in Part:

To: Aspen Aerogels, Inc.

The undersigned                                              

Please insert Social Security or other

identifying number of Subscriber:

hereby irrevocably elects to exercise the right of purchase represented by this Warrant for, and to purchase thereunder,             shares of the Common Stock provided for therein and tenders payment herewith to the order of Aspen Aerogels, Inc. in the amount of $            , in one or more of the forms permitted by this Warrant.

The undersigned requests that certificates for such shares of Common Stock be issued as follows:

Name:                                                                                                                                                                                                                                                          

Address:                                                                                                                                                                                                                                                      

Deliver to:                                                                                                                                                                                                                                                 

Address:                                                                                                                                                                                                                                                      

and, if such number of shares of Common Stock shall not be all the shares of Common Stock purchasable hereunder, that a new Warrant for the balance remaining of the shares of Common Stock purchasable under this Warrant be registered in the name of, and delivered to, the undersigned at the address stated above.

Dated:

Signature
	Note: The signature on this Subscription Form must correspond with the name as written upon the face of this Warrant in every particular, without alteration or enlargement or any change whatever.

1

EX-4.7

Exhibit 4.7

EXECUTION COPY

THIS WARRANT AND THE CAPITAL STOCK ISSUABLE UPON EXERCISE HEREOF HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. SUCH SECURITIES MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED, HYPOTHECATED, DISTRIBUTED, TRANSFERRED OR OTHERWISE DISPOSED EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY STATING THAT REGISTRATION IS NOT REQUIRED UNDER SAID ACT.

THE SALE, ASSIGNMENT, HYPOTHECATION, PLEDGE, ENCUMBRANCE OR OTHER DISPOSITION AND VOTING OF ANY OF THE SHARES OF SERIES C PREFERRED STOCK OF THE COMPANY ACQUIRED PURSUANT TO THE EXERCISE OF THIS WARRANT ARE RESTRICTED BY THE TERMS OF THE SIXTH AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT (THE “STOCKHOLDERS’ AGREEMENT”), DATED AS OF MARCH 28, 2013, AMONG THE COMPANY AND CERTAIN OF ITS STOCKHOLDERS. THE COMPANY WILL NOT REGISTER THE TRANSFER OF SUCH SHARES OF SERIES C PREFERRED STOCK ON THE BOOKS OF THE COMPANY UNLESS AND UNTIL THE TRANSFER HAS BEEN MADE IN COMPLIANCE WITH THE TERMS OF THE STOCKHOLDERS’ AGREEMENT, A COPY OF WHICH WILL BE PROVIDED AT NO COST TO THE HOLDER HEREOF UPON WRITTEN REQUEST TO THE COMPANY.

Warrant No. __ Date of Issuance:                     , 2013                                        Number of Shares:                                                                     (subject to adjustment)

ASPEN AEROGELS, INC.

SERIES C PREFERRED STOCK PURCHASE WARRANT

ASPEN AEROGELS, INC. (the “Company”), for value received, hereby certifies that [REGISTERED HOLDER], or its registered assigns (the “Registered Holder”), is entitled, subject to the terms set forth herein, to purchase from the Company, at any time after the date hereof and on or before March 28, 2023 (the “Expiration Date”), up to [            ] ([            ]) shares, as adjusted from time to time pursuant to the provisions of this Warrant, of Series C Preferred Stock of the Company, par value $0.00001 per share, at an exercise price of $0.00001 per share. As used herein, “Series C Preferred Stock” shall mean the shares of preferred stock designated as Series C Convertible Preferred Stock, par

value $0.00001 per share, as of the Date of Issuance of this Warrant under the Company’s Fourth Amended and Restated Certificate of Incorporation, as amended (the “Certificate of Incorporation”). The security and the specific shares issuable upon exercise of this Warrant and the exercise price per share, each as adjusted from time to time pursuant to the provisions of this Warrant, are sometimes hereinafter referred to as the “Underlying Stock,” the “Warrant Stock” and the “Exercise Price,” respectively.

This Warrant is one of several warrants issued pursuant to that certain Note and Warrant Purchase Agreement, dated March 28, 2013 between the Company and the purchasers signature thereto (the “Agreement”). Capitalized terms not otherwise defined herein shall have the meanings ascribed to such terms in the Agreement.

1. EXERCISE OF WARRANT

Section 1.1. Payment. Subject to compliance with the terms and conditions of this Warrant and applicable securities laws, this Warrant may be exercised by the Registered Holder, in whole or in one or more parts, at any time or from time to time, on or before the Expiration Date by the delivery of the form of Notice of Exercise attached hereto as Exhibit A (the “Notice of Exercise”), duly executed by the Registered Holder or by such Registered Holder’s duly authorized attorney, to the principal office of the Company, or such other office or agency as the Company may designate, accompanied by this Warrant and payment in full of the aggregate Exercise Price payable in respect of the number of shares of Warrant Stock purchased upon such exercise (the “Purchase Price”); provided, however, that if the Registered Holder is subject to HSR Act Restrictions (as defined in Section 1.4 below), the Purchase Price shall be paid to the Company within five business days of the termination of all HSR Act Restrictions. The Purchase Price may be paid by cash, check or wire transfer of immediately available funds to the Company. Notwithstanding any provision of this Warrant to the contrary, however, this Warrant may not be exercised if such exercise, either alone or together with the exercise of other Warrants or acquisitions of stock of the Company would (i) if the Registered Holder (other than GKFF Ventures I, LLC and their affiliates, successors and assigns (“GKFF Ventures”) and Reservoir Capital Group, L.L.C. and their affiliates, successors and assigns (“Reservoir”)) is not a “5-percent shareholder” (within the meaning of Section 382 of the Internal Revenue Code of 1986, as amended (the “Code”), cause the Registered Holder to become a 5-percent shareholder, (ii) if the Registered Holder (other than GKFF Ventures and Reservoir) is a 5-percent shareholder, cause the percentage of stock of the Company treated as owned by the Registered Holder under Section 382 of the Code to increase, or (iii) cause the Registered Holder to own more than 50% of the stock of the Company for purposes of Section 382 of the Code; provided, however, that the limitations described above shall not apply to any exercise in connection with an IPO, a Sale of the Corporation (as defined in the Certificate of Incorporation) or Liquidation (as defined in the Certificate of Incorporation) of the Company and, provided further, that the limitations described in clauses (i) and (ii) above may be waived by the Company’s Board of Directors with respect to a Registered Holder. Each Registered Holder hereby agrees that, prior to exercising its Warrant(s) or a portion thereof, it shall first provide written notice to GKFF Ventures and Reservoir at least three business days prior to such exercise, which notice shall specify the number of shares of Warrant Stock intended to be exercised. Any exercise of this Warrant other than in accordance with the foregoing limitation shall be void ab initio.

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Section 1.2. Net Issue Exercise.

(a) In lieu of exercising this Warrant in the manner provided in Section 1.1, the Registered Holder may elect to receive shares of Warrant Stock equal to the value of this Warrant (or the portion thereof being canceled) by surrender of this Warrant at the principal office of the Company together with the Notice of Exercise duly executed by the Registered Holder or such Registered Holder’s duly authorized attorney, in which event the Company shall issue to the Registered Holder a number of shares of Warrant Stock computed using the following formula:

X =       Y (A - B)

                    A

Where	X =	The number of shares of Warrant Stock to be issued to the Registered Holder.
	Y =	The number of shares of Warrant Stock exercised under this Warrant (as adjusted to the date of such calculation).
	A =	The Fair Market Value of one share of Warrant Stock (as adjusted to the date of such calculation).
	B =	The Exercise Price (as adjusted to the date of such calculation).

All references herein to an “exercise” of the Warrant in this Warrant shall include an exchange pursuant to this Section 1.2.

(b) Subject to Section 1.3(b), for purposes of this Warrant, the term “Fair Market Value” of a share of Warrant Stock as of a particular date shall mean:

(i) If the Underlying Stock is traded on a securities exchange, the Fair Market Value shall be deemed to be the average of the closing prices thereof on such exchange over the 10 trading days ending immediately prior to (but not including) the applicable date of valuation;

(ii) If the Underlying Stock is actively traded over-the-counter, the Fair Market Value shall be deemed to be the average of the closing bid prices over the 10-day period ending immediately prior to (but not including) the applicable date of valuation;

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(iii) If there is no active public market for the Underlying Stock but there is an active public market for a class or series of capital stock of the Company into which the Underlying Stock is convertible, then if such class or series of capital stock is:

(A) traded on a securities exchange, the Fair Market Value shall be deemed to be the average of the closing prices of a share of such class or series of capital stock of the Company on such exchange over the 10 trading days ending immediately prior to (but not including) the applicable date of valuation multiplied by the number of shares of such class or series of capital stock into which one share of the Underlying Stock is convertible, or

(B) actively traded over-the-counter, the Fair Market Value shall be deemed to be the average of the closing bid prices for a share of such class or series of capital stock of the Company over the 10-day period ending immediately prior to (but not including) the applicable date of valuation multiplied by the number of shares of such class or series of capital stock into which one share of the Underlying Stock is convertible; or

(iv) If there is no active public market for the Underlying Stock or any other class or series of capital stock of the Company into which the Underlying Stock is convertible, the Fair Market Value shall be the highest price per share which the Company could obtain on the date of calculation from a willing buyer (not a current employee or director) for shares of Underlying Stock sold by the Company, from authorized but unissued shares, as reasonably determined in good faith by the Board of Directors.

If the Registered Holder hereof does not agree with the determination of Fair Market Value as determined by the Board of Directors, the Company and the Registered Holder hereof shall negotiate an appropriate Fair Market Value. If after ten (10) days, the Company and the Registered Holder cannot agree, then the Registered Holder may request that the Fair Market Value be determined by a valuation firm of national reputation selected by the Company and reasonably acceptable to the Registered Holder. The fees and expenses of such valuation firm shall be borne by the Company unless the Fair Market Value determined by such valuation firm is equal to or less than the Fair Market Value as determined by the Company, in which event the fees and expenses of such valuation firm shall be borne by the Registered Holder hereof. Notwithstanding the foregoing, if a two-thirds majority of the holders of Warrants issued pursuant to the Agreement outstanding at such date agree with the determination of Fair Market Value as determined by the Board of Directors, then such determination of Fair Market Value shall be final and binding upon such Registered Holder.

Section 1.3 Significant Transactions.

(a) The Company shall provide the Registered Holder with written notice of the Company’s intention to:

(i) raise capital by selling shares of the Underlying Stock (or shares of capital stock into which Underlying Stock is convertible) in a firm commitment underwritten initial public offering (an “IPO” and, such notice of an IPO, an “IPO Notice”), or

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(ii) enter into a definitive agreement providing for (A) a merger or consolidation of the Company or any of its subsidiaries with or into another corporation (with respect to which less than a majority of the outstanding voting power or equity securities of the surviving or consolidated corporation immediately following such event is held by persons or entities who were stockholders of the Company immediately prior to such event); (B) the sale, license, disposition or other transfer of all or substantially all of the properties and assets of the Company or any of its subsidiaries; (C) except as a result of the exercise of the Warrants by the Warrant holders or the conversion of either the Notes or the Prior Notes by the holders of such notes, (x) any acquisition by any person (or group of affiliated or associated persons) of beneficial ownership of a majority of the equity of the Company or of any subsidiary (whether or not newly-issued shares) in a single transaction or a series of related transactions; or (y) any other similar change of control of fifty percent (50%) or more of the outstanding voting power of the Company or any subsidiary (each, an “Acquisition” and, such notice of an Acquisition, an “Acquisition Notice”),

with such notice delivered to the Registered Holder at least five but not more than 90 days before the anticipated date of the filing with the Securities and Exchange Commission (the “SEC”) of the registration statement associated with an IPO or the anticipated date of execution of the definitive agreement providing for an Acquisition, as applicable. An IPO Notice or Acquisition Notice, as applicable, shall include a brief summary of the transaction, the contemplated timeframe for completion, the material terms thereof and the consideration payable in respect of one share of Underlying Stock (or shares of capital stock into which Underlying Stock is convertible), in each case to the extent known by the Company at such time. To the extent information with respect to the consideration payable in respect of one share of Underlying Stock (or shares of capital stock into which Underlying Stock is convertible) in such transaction is not definitively known at the time of delivery of such notice, the Company shall provide a reasonable estimate thereof (which may include a range), and shall promptly supplement such notice if and at such time as such estimate or any other information included in the original notice is no longer reasonable or materially changes. The Registered Holder shall provide notice to the Company within five business days of receipt of the IPO Notice or the Acquisition Notice, as applicable, if the Registered Holder will exercise this Warrant pursuant to this Section 1.3 in connection with the IPO or the Acquisition, as applicable. If the Registered Holder is electing to exercise this Warrant in part or in full, such notice shall be given pursuant to the Notice of Exercise.

(b) An exercise of the Warrant pursuant to this Section 1.3 shall be effected in accordance with Section 1.2, except as otherwise set forth in this Section 1.3. Notwithstanding whether (i) an IPO Notice has been delivered to the Registered Holder or any other provision of this Warrant to the contrary, if the Registered Holder decides to exercise this Warrant while a registration statement is on file with the SEC in connection with the IPO, or (ii) an Acquisition Notice has been delivered to the Registered Holder or any other provision of this Warrant to the contrary, if the Registered Holder decides to exercise this Warrant following the execution of a definitive agreement providing for an

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Acquisition but prior to the consummation of the Acquisition, this Warrant shall automatically be deemed exercised immediately prior to the consummation of the IPO or Acquisition, as applicable, and the Fair Market Value of a share of Warrant Stock will be, (x) in the context of an IPO, the price at which one share of Underlying Stock was sold to the public in the IPO, or if the Underlying Stock is not the capital stock being offered to the public in the IPO, the price at which one share of the capital stock being offered to the public in the IPO was sold to the public in the IPO multiplied by the number of shares of such capital stock into which one share of Underlying Stock is then convertible, or (y) in the context of an Acquisition, the deemed value of the consideration payable in respect of one share of Underlying Stock to be received by the holders of such stock pursuant to the definitive agreement providing for such Acquisition.

(c) If the Registered Holder has elected to exercise this Warrant pursuant to this Section 1.3 while a registration statement is on file with the SEC in connection with an IPO or prior to the consummation of the Acquisition, as applicable, and the transaction triggering the delivery of an IPO Notice or Acquisition Notice, as applicable, is not consummated, then the exercise of this Warrant shall not be effective unless the Registered Holder confirms in writing the Registered Holder’s intention to go forward with the exercise of this Warrant.

Section 1.4 HSR Act. The Company hereby acknowledges that exercise of this Warrant by the Registered Holder may subject the Company and/or the Registered Holder to the filing requirements under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (the “HSR Act”) and that the Registered Holder may be prevented from exercising this Warrant until the expiration or early termination of all waiting periods imposed by the HSR Act (“HSR Act Restrictions”). If on or before the Expiration Date the Registered Holder has delivered the Notice of Exercise to the Company and the Registered Holder has not been able to complete the exercise of this Warrant prior to the Expiration Date because of HSR Act Restrictions, the Registered Holder shall be entitled to complete the process of exercising this Warrant as noted in the Notice of Exercise delivered prior to the Expiration Date in accordance with the procedures set forth herein notwithstanding the fact that completion of such exercise would take place after the Expiration Date or the completion of the IPO or an Acquisition, as applicable.

Section 1.5 Effective Time of Exercise. Subject to Section 1.3, the exercise of this Warrant shall be deemed to have been effected immediately prior to the close of business on the day on which this Warrant shall have been surrendered to the Company as provided in Section 1.1 or Section 1.2 above, as applicable. However, if the Registered Holder is subject to HSR Act filing requirements (a) this Warrant shall be deemed to have been exercised on the date immediately following the date of the expiration of all HSR Act Restrictions and (b) for the purposes of the net issue provisions of Section 1.2, the Fair Market Value of one share of Warrant Stock shall be determined as of the date of the Notice of Exercise. The person entitled to receive the shares of Warrant Stock issuable upon exercise of this Warrant shall be treated for all purposes as the holder of record of such shares as of the close of business on the date the Registered Holder is deemed to have exercised this Warrant.

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Section 1.6. Stock Certificates; Fractional Shares; Partial Exercise.

(a) As soon as practicable on or after the date of exercise determined in accordance with Section 1.5, the Company shall issue the shares of Warrant Stock and, unless the Registered Holder requests that such shares be uncertificated, deliver to the person or persons entitled to receive the shares of Warrant Stock issuable upon exercise hereof, a certificate or certificates for the number of whole shares of Warrant Stock issuable upon such exercise.

(b) No fractional shares or scrip representing fractional shares shall be issued upon an exercise of this Warrant. In lieu of any fraction shares which would otherwise be issuable, the Company shall pay cash equal to the product of such fraction multiplied by the Fair Market Value of one share of Warrant Stock on the date of exercise determined in accordance with Section 1.5.

(c) In case of any partial exercise of this Warrant, the Company shall cancel this Warrant and shall execute and deliver a new warrant or warrants (dated the date hereof) of like tenor and with the same date, calling in the aggregate on the face or faces thereof for the number of shares of Warrant Stock equal (without giving effect to any adjustment thereof) to the number of such shares called for on the face of this Warrant minus the number of such shares purchased by the Registered Holder upon such exercise as provided in this Section 1 (without giving effect to any adjustment thereof).

Section 1.7. Stockholders’ Agreement. If the Registered Holder is not already a party thereto, the Registered Holder shall also execute a joinder agreement to each of the Stockholders’ Agreement and the Sixth Amended and Restated Registration Rights Agreement, dated as of June 11, 2012, as may be amended and modified from time to time.

Section 1.8. Payment of Taxes. The Company shall pay all expenses, taxes and other governmental charges with respect to the issue or delivery of the shares of Warrant Stock, unless such tax or charge is imposed by law upon the Registered Holder.

2. ADJUSTMENT OF NUMBER OF SHARES AND EXERCISE PRICE

The number of shares of Warrant Stock issuable upon exercise of this Warrant and the Exercise Price are subject to adjustment as follows:

Section 2.1. Adjustment for Stock Splits, Stock Subdivisions or Combinations of Shares. If all or any portion of the outstanding shares of the Underlying Stock shall be subdivided into a greater number of shares, the Exercise Price in effect immediately prior to such subdivision shall simultaneously with the effectiveness of such subdivision be proportionately reduced. If all or any portion of the outstanding shares of the Underlying Stock shall be combined into a smaller number of shares, the Exercise Price in effect immediately prior to such combination shall, simultaneously with the effectiveness of such combination, be proportionately increased. When any adjustment is required to be made in the Exercise Price, the number of shares of Warrant Stock purchasable upon the exercise of this Warrant shall be changed to the number determined by dividing (a) an amount equal to the number of shares issuable upon the exercise of this Warrant immediately prior to such adjustment, multiplied by the Exercise Price in effect immediately prior to such adjustment, by (b) the Exercise Price in effect immediately after such adjustment.

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Section 2.2. Adjustment for Dividends or Distributions of Stock or Other Securities or Property. In case the Company shall make or issue, or shall fix a record date for the determination of eligible holders entitled to receive, a dividend or other distribution with respect to all or any portion of the outstanding shares of the Underlying Stock payable in (a) securities of the Company or (b) assets (excluding cash dividends paid or payable solely out of retained earnings), then, in each such case, the Registered Holder on exercise hereof at any time after the consummation, effective date or record date of such dividend or other distribution, shall receive, in addition to the shares of Warrant Stock issuable on such exercise prior to such date, and without the payment of additional consideration therefor, the securities or such other assets of the Company to which the Registered Holder would have been entitled upon such date if the Registered Holder had exercised this Warrant on the date hereof and had thereafter, during the period from the date hereof to and including the date of such exercise, retained such shares and/or all other additional stock available by it as aforesaid during such period giving effect to all adjustments called for by this Section 2.

Section 2.3. Reclassification. If the Company, by reclassification of securities or otherwise, shall change the Underlying Stock into the same or a different number of securities of any other class or classes, this Warrant shall thereafter represent the right to acquire such number and kind of securities as would have been issuable as the result of such change with respect to the Underlying Stock immediately prior to such reclassification or other change and the Exercise Price therefore shall be appropriately adjusted, all subject to further adjustment as provided in this Section 2.

Section 2.4. Adjustment for Capital Reorganization, Merger or Consolidation. In case of any capital reorganization of the capital stock of the Company (other than a combination, reclassification, exchange or subdivision of shares otherwise provided for herein), any Acquisition or any other merger or consolidation of the Company with or into another organization, or the sale of all or substantially all the assets of the Company then, and in each such case, as a part of such transaction, lawful provision shall be made so that the Registered Holder shall thereafter be entitled to receive upon exercise of this Warrant, during the period specified herein and upon payment of the applicable Purchase Price, the number of shares of stock or other securities or property of the successor organization resulting from such transaction that a holder of the securities deliverable upon exercise of this Warrant would have been entitled to receive in such transaction if this Warrant had been exercised immediately before such transaction, all subject to further adjustment as provided in this Section 2. The foregoing provisions of this Section 2.4 shall similarly apply to successive acquisitions, reorganizations, consolidations, mergers, sales, transfers and similar transactions and to the stock or securities of any other organizations that are at the time receivable upon the exercise of this Warrant. If the per-share consideration payable to the Registered Holder for shares in connection with any such transaction is in a form other than cash, then the provisions of Section 1.2(b) shall be applied except that

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each reference to Warrant Stock shall be replaced by the consideration payable in connection with such transaction. If the provisions of Section 1.2(b) cannot be applied to value such consideration, then the value of such consideration shall be determined in good faith by the Company’s Board of Directors. In all events, appropriate adjustment, as determined in good faith by the Company’s Board of Directors, shall be made in the application of the provisions of this Warrant with respect to the rights and interests of the Registered Holder after the transaction, to the end that the provisions of this Warrant shall be applicable after that event, as near as reasonably may be, in relation to any shares or other property deliverable after that event upon exercise of this Warrant. Notwithstanding the foregoing, if the Company’s Board of Directors and a two-thirds majority of the holders of Warrants issued pursuant to the Agreement then outstanding agree, in any such Acquisition or any other acquisition, reorganization, merger, consolidation, sale or transfer described above, the Warrants issued pursuant to the Agreement will be converted into the right to receive the consideration that the Warrant Stock would receive in such transaction and upon the consummation of such transaction the Warrants will cease to be outstanding.

Section 2.5 Certificate as to Adjustments. When any adjustment in the Exercise Price or the number or type of shares issuable upon exercise of this Warrant is required to be made pursuant to this Section 2, an authorized officer of the Company shall compute such adjustment in accordance with the terms of this Warrant and prepare a certificate setting forth (a) a brief statement of the facts upon which such adjustment is based, (b) the Exercise Price after such adjustment and (c) the kind and amount of stock into which this Warrant shall be exercisable after such adjustment. The Company shall promptly send (by facsimile and by either first class mail, postage prepaid or overnight delivery) a copy of each such certificate to the Registered Holder.

3. TRANSFERS

Section 3.1 Unregistered Securities. Each holder of this Warrant acknowledges that this Warrant and the Warrant Stock have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), and agrees not to sell, offer for sale, pledge, hypothecate, distribute, transfer or otherwise dispose of this Warrant or any Warrant Stock issued upon its exercise in the absence of (a) an effective registration statement under the Securities Act as to this Warrant or such Warrant Stock and registration or qualification of this Warrant or such Warrant Stock under any applicable U.S. federal or state securities law then in effect, or (b) an opinion of counsel (which may be counsel for the Company), satisfactory to the Company, that such registration and qualification are not required. Each certificate or other instrument for Warrant Stock issued upon the exercise of this Warrant pursuant to Section 1.6(a), or in the case of uncertificated shares, the ledger entry reflecting the issuance of such Warrant Stock, shall bear a legend substantially as follows:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF AND HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED. SUCH SHARES MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED, HYPOTHECATED,

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DISTRIBUTED, TRANSFERRED OR OTHERWISE DISPOSED OF IN THE ABSENCE OF SUCH REGISTRATION OR UNLESS THE COMPANY RECEIVES AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY STATING THAT SUCH SALE OR TRANSFER IS EXEMPT FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SAID ACT.

THE SALE, ASSIGNMENT, HYPOTHECATION, PLEDGE, ENCUMBRANCE OR OTHER DISPOSITION AND VOTING OF SUCH SHARES ARE RESTRICTED BY THE TERMS OF THE SIXTH AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT, DATED AS OF MARCH 28, 2013, AMONG THE COMPANY AND CERTAIN OF ITS STOCKHOLDERS. THE COMPANY WILL NOT REGISTER THE TRANSFER OF SUCH SHARES ON THE BOOKS OF THE COMPANY UNLESS AND UNTIL THE TRANSFER HAS BEEN MADE IN COMPLIANCE WITH THE TERMS OF THE STOCKHOLDERS’ AGREEMENT, A COPY OF WHICH WILL BE PROVIDED AT NO COST TO THE HOLDER HEREOF UPON WRITTEN REQUEST TO THE COMPANY.”

Section 3.2 Transferability.

(a) Subject to the provisions of this Warrant, including Sections 3.1 and 6.5, and the Stockholders’ Agreement and compliance with all applicable securities laws, this Warrant and all rights and obligations hereunder may be transferred to any person, in whole or in part, on the books of the Company maintained pursuant to Section 3.3 upon surrender of the Warrant with a properly executed form of Assignment attached hereto as Exhibit B (the “Form of Assignment”) at the principal office of the Company. Upon the proper surrender by the Registered Holder of the Warrant, the Company will issue and deliver to or upon the order of the Registered Holder a new Warrant or Warrants of like tenor as such Registered Holder may direct, calling in the aggregate on the face or faces thereof for the number of shares of Warrant Stock called for on the face of the Warrant so surrendered; provided, however, that no such transfer may be made to any direct competitor of the Company, which shall mean a Person engaged in the research, manufacture or sale of aerogels, aerogel based products or insulation products, other than in connection with a Sale of the Corporation (as defined in the Certificate of Incorporation). The Company may issue stop transfer instructions to its transfer agent in connection with the foregoing restrictions.

(b) Each taker and holder of this Warrant, by taking or holding the same, consents and agrees that when this Warrant shall have been so endorsed, the person in possession of this Warrant may be treated by the Company, and all other persons dealing with this Warrant, as the absolute owner hereof and as the Registered Holder for any purpose and as the person entitled to exercise the rights represented hereby, any notice to the contrary notwithstanding.

Section 3.3 Warrant Register. The Company will maintain a register containing the names and addresses of the Registered Holder of this Warrant, and will promptly update such register to reflect any transfers in compliance with the terms hereof. Any Registered Holder may change such Registered Holder’s address as shown on the warrant register by written notice to the Company requesting such change.

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4. COVENANTS OF THE COMPANY

Section 4.1 Reservation of Capital Stock. The Company hereby covenants that at all times there shall be reserved for issuance and delivery upon exercise of this Warrant such number of shares of Underlying Stock as may be issuable from time to time upon exercise hereof in full and any common stock of the Company issuable from time to time upon conversion of such Underlying Stock and, from time to time, will take all steps necessary to amend its Certificate of Incorporation to provide sufficient reserves of shares of Underlying Stock and common stock of the Company.

Section 4.2 No Impairment. The Company will not, by amendment of its Certificate of Incorporation or Bylaws, or through reorganization, consolidation, merger, dissolution, issue or sale of securities, sale of assets or any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the Registered Holder against impairment.

Section 4.3 Replacement Warrants. Upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant, and, in the case of loss, theft or destruction, of such bond or indemnification as the Company may reasonably require, and, in the case of such mutilation, upon surrender and cancellation of this Warrant, the Company will issue, in lieu thereof, a new Warrant of like tenor.

5. NOTICES

Section 5.1 Record Dates. Notwithstanding the provisions of Section 1.3, in case:

(a) the Company shall set a record date for the holders of the Underlying Stock for the purpose of entitling or enabling them to receive any dividend or other distribution (excluding cash dividends paid or payable solely out of retained earnings), or to receive any right to subscribe for or purchase any shares of stock of any class or any other securities, or to receive any other right;

(b) of any capital reorganization of the Company, any reclassification of the capital stock of the Company, any consolidation or merger of the Company with or into another organization (other than a consolidation or merger in which the Company is the surviving entity), or any transfer of all or substantially all of the assets of the Company; or

(c) of the voluntary or involuntary dissolution, liquidation or winding-up of the Company,

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then, and in each such case, the Company will mail or cause to be mailed to the Registered Holder of this Warrant a notice specifying, as the case may be, (i) the record date for the purpose of such dividend, distribution or right, and stating the amount and character of such dividend, distribution or right, or (ii) the effective date on which such reorganization, reclassification, consolidation, merger, transfer, dissolution, liquidation or winding-up is to take place, and the time, if any is to be fixed, as of which the holders of record of capital stock of the Company (or such other securities at the time deliverable upon such reorganization, reclassification, consolidation, merger, transfer, dissolution, liquidation or winding-up) are to be determined and the material terms and conditions of the impending transaction. In each such case, the notice shall be provided at least five business days prior to the record date or effective date for the event specified in such notice, in each case in accordance with the provisions of Section 5.2.

Section 5.2 Generally. Unless otherwise provided herein, any notice required or permitted by this Warrant shall be in writing and shall be deemed sufficient upon delivery, when delivered personally or by overnight courier or sent by facsimile or electronic mail, or 48 hours after being deposited in the U.S. mail, as certified or registered mail, with postage prepaid, addressed to the party to be notified at such party’s address as set forth on the signature page, or as subsequently modified by written notice.

6. MISCELLANEOUS

Section 6.1 No Rights or Liabilities as a Stockholder. This Warrant shall not entitle the Registered Holder to any voting rights or other rights as a stockholder of the Company. In the absence of affirmative action by the Registered Holder to purchase Warrant Stock by exercise of this Warrant, no provisions of this Warrant, and no enumeration herein of the rights or privileges of the Registered Holder hereof, shall cause the Registered Holder to be or have any rights of a stockholder of the Company for any purpose.

Section 6.2 Survival of Representations and Warranties. Unless otherwise set forth in this Warrant, the warranties, representations and covenants of the Company and the Registered Holder contained in or made pursuant to this Warrant shall survive the execution and delivery of this Warrant.

Section 6.3 Amendment and Modification. This Warrant is one in a series of Warrants issued pursuant to the Agreement and this Warrant may not be amended, modified or supplemented in any manner, whether by course of conduct or otherwise, except by an instrument in writing specifically designated as an amendment hereto, signed by the Company and a two-thirds majority of the holders of Warrants issued pursuant to the Agreement outstanding at the time of the amendment. Notwithstanding the foregoing, this Warrant may not be amended or terminated with respect to the Registered Holder without the written consent of the Registered Holder unless such amendment or termination applies to all holders of Warrants issued pursuant to the Agreement in the same fashion.

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Section 6.4 Waiver. No failure or delay of any party in exercising any right or remedy hereunder shall operate as a waiver thereof, nor shall any single or partial exercise of any such right or power, or any abandonment or discontinuance of steps to enforce such right or power, or any course of conduct, preclude any other or further exercise thereof or the exercise of any other right or power. Any agreement on the part of a party hereto to waive any right or power hereunder shall be valid only if set forth in a written instrument executed and delivered by the Company and a two-thirds majority of the holders of Warrants issued pursuant to the Agreement outstanding at the time of the waiver. Notwithstanding the foregoing and except as provided otherwise herein, no provision, right or power under this Warrant may be waived with respect to the Registered Holder without the written consent of the Registered Holder unless such waiver applies to all holders of Warrants issued pursuant to the Agreement in the same fashion. The rights and remedies of the parties hereunder are cumulative and are not exclusive of any rights or remedies which they would otherwise have hereunder.

Section 6.5 Assignment; Successors and Assigns. This Warrant and any of the rights, interests or obligations under this Warrant may be assigned or delegated, in whole or in part, by operation of law or otherwise, by the Registered Holder in compliance with the terms of this Warrant, applicable securities laws and the Stockholders’ Agreement. Subject to the preceding sentence, this Warrant will be binding upon, inure to the benefit of, and be enforceable by, the parties and their respective successors and assigns.

Section 6.6 Interpretation. When a reference is made in this Warrant to a Section or Exhibit such reference shall be to a Section or Exhibit of this Warrant unless otherwise indicated. The headings contained in this Warrant or in any Exhibit are for convenience of reference purposes only and shall not affect in any way the meaning or interpretation of this Warrant. All words used in this Agreement will be construed to be of such gender or number as the circumstances require. Any capitalized terms used in any Exhibit but not otherwise defined therein shall have the meaning as defined in this Warrant. All Exhibits annexed hereto or referred to herein are hereby incorporated in and made a part of this Warrant as if set forth herein. The word “including” and words of similar import when used in this Agreement will mean “including, without limitation,” unless otherwise specified.

Section 6.7 Governing Law. This Warrant and all disputes or controversies arising out of or relating to this Warrant or the transactions contemplated hereby shall be governed by, and construed in accordance with, the internal laws of the State of Delaware, without regard to the laws of any other jurisdiction that might be applied because of the conflicts of laws principles of the State of Delaware.

Section 6.8 Severability. Whenever possible, each provision or portion of any provision of this Warrant shall be interpreted in such manner as to be effective and valid under applicable law, but if any provision or portion of any provision of this Warrant is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any jurisdiction, such invalidity, illegality or unenforceability shall not affect any other provision or portion of any provision in such jurisdiction, and this Warrant shall be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or unenforceable provision or portion of any provision had never been contained herein.

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Section 6.9 Counterparts. This Warrant may be executed in two or more counterparts, all of which shall be considered one and the same instrument and shall become effective when one or more counterparts have been signed by each of the parties and delivered to the other parties.

[The remainder of this page is intentionally left blank.]

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IN WITNESS WHEREOF, the parties hereto have executed this Warrant as of the Effective Date.

ASPEN AEROGELS, INC.

By:

Name:

Title:

Address:

Attention:

Facsimile:

E-mail:

Acknowledged and Agreed:
REGISTERED HOLDER:
Name of Registered Holder (Print or Type)
By:
	Name of Entity
	Its:
(Complete above if another entity signs for Registered Holder listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)
Address:
Attention:
Facsimile:
E-mail:

Signature Page to Series C Preferred Stock Purchase Warrant

Warrant No.             

EXHIBIT A

NOTICE OF EXERCISE

SERIES C PREFERRED STOCK PURCHASE WARRANT

(To be executed upon exercise of Warrant No.     )

The undersigned hereby irrevocably elects to exercise the right of purchase represented by Warrant No.      for, and to purchase thereunder, the securities of ASPEN AEROGELS, INC. as provided for therein, and (check the applicable box(es)):

¨ Tenders herewith payment of the Purchase Price in the form of cash or a certified or official bank check in same-day funds (or has initiated a wire) in the amount of $            for             shares of Warrant Stock.

¨ Elects a Net Issue Exercise pursuant to Section 1.2 (or Section 1.3), and accordingly requests delivery of a net of             shares of Warrant Stock, calculated in accordance with Section 1.2.

Such Notice is being provided in response to (if applicable):

¨ IPO Notice ¨ Acquisition Notice

Note: The above signature must correspond to the name as written upon the face of the Warrant in every particular, without alteration or any change whatsoever. If said number of Warrant Shares shall not be all of the Warrant Shares purchasable under the Warrant, a new Warrant is to be issued in the name of said undersigned for the balance remaining of the Warrant Shares purchasable thereunder.

Notice of Exercise

EXHIBIT B

ASSIGNMENT

SERIES C PREFERRED STOCK PURCHASE WARRANT

(To be executed upon assignment of Warrant No.     )

For value received, the undersigned hereby sells, assigns and transfers unto                                 the within Warrant, together with all right, title and interest therein, and does hereby irrevocably constitute and appoint                                 attorney, to transfer said Warrant on the books of ASPEN AEROGELS, INC. with respect to the number of shares of Warrant Stock set forth below, with full power of substitution in the premises:

Name(s) of Assignee(s) Address # of Shares of Warrant Stock

And if said number of shares of Warrant Stock shall not be all the number of shares of Warrant Stock represented by the Warrant, a new Warrant is to be issued in the name of said undersigned for the balance remaining of the Warrants registered by said Warrant.

Dated:                                                                  

Signature:                                                           

Note: The signature to the foregoing Assignment must correspond to the name as written upon the face of the Warrant in every particular, without alteration or any change whatsoever.

Form of Assignment

EX-4.8

Exhibit 4.8

ASPEN AEROGELS, INC.

SIXTH AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

THIS SIXTH AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT (“Agreement”), dated as of June 11, 2012, is by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Investors set forth on Schedule A hereto (the “Investors”).

Recitals:

A. The Company was formed as Aspen Merger Sub, Inc. on May 16, 2008 by filing its Certificate of Incorporation with the Secretary of the State of Delaware. The Company entered into an Agreement and Plan of Merger with Aspen Aerogels, Inc., a Delaware corporation (the “Predecessor Entity”), on June 10, 2008, pursuant to which the Predecessor Entity merged with and into the Company (the “Merger”), with the Company surviving the Merger, and the Company changed its name to “Aspen Aerogels, Inc.” as part of the Merger.

B. In connection with the issuance of the Predecessor Entity’s Series A Convertible Preferred Stock on May 17, 2001, the Predecessor Entity and certain Stockholders entered into that certain Registration Rights Agreement dated as of such date (the “Original Agreement”).

C. In connection with the issuance of the Predecessor Entity’s Series C Convertible Preferred Stock on December 9, 2003, the Predecessor Entity and certain Stockholders entered into that certain First Amended and Restated Registration Rights Agreement dated as of such date, as amended on October 20, 2004 (as so amended, the “Amended Agreement”) replacing the Original Agreement in its entirety.

D. In connection with the issuance of the Predecessor Entity’s Series D Preferred Stock on March 23, 2005, the Predecessor Entity and certain Stockholders entered into that certain Second Amended and Restated Registration Rights Agreement dated as of such date (the “Second Amended Agreement”) replacing the Amended Agreement in its entirety.

E. In connection with the issuance of the Company’s formerly outstanding Series B-1 Preferred Stock on June 10, 2008, the Company and certain Stockholders entered into that certain Third Amended and Restated Registration Rights Agreement dated as of such date (the “Third Amended Agreement”) replacing the Second Amended Agreement in its entirety.

F. In connection with the issuance of the Company’s Series A Preferred Stock on August 14, 2009, the Company and certain Stockholders entered into that certain Fourth Amended and Restated Registration Rights Agreement dated as of such date (the “Fourth Amended Agreement”) replacing the Third Amended Agreement in its entirety.

G. In connection with the issuance of the Company’s Series B Preferred Stock on September 22, 2010, the Company and certain Stockholders entered into that certain Fifth Amended and Restated Registration Rights Agreement dated as of such date (the “Fifth Amended Agreement”) replacing the Fourth Amended Agreement in its entirety.

H. The Fifth Amended Agreement was further amended on December 29, 2010, June 1, 2011, June 14, 2011 and on December 6, 2011.

I. Certain Investors (the “Purchasers”) will purchase June 2012 Notes (defined below) pursuant to a Note Purchase Agreement, dated as of the date hereof, by and among the Company and the Purchasers (the “Purchase Agreement”).

J. The Company and the Majority Holders under the Fifth Amended Agreement, together with the Purchasers, desire to amend and restate the Fifth Amended Agreement by deleting it in its entirety and replacing it with this Agreement.

K. The Company and the Investors desire to enter into this Agreement for the purpose of establishing the registration rights of the Common Stock.

L. The execution and delivery of this Agreement is a condition to the Purchasers’ purchase of June 2012 Notes pursuant to the Purchase Agreement.

Agreement:

NOW, THEREFORE, for and in consideration of the foregoing and of the mutual covenants and agreements hereinafter set forth, the parties hereto agree as follows:

Section 1. Definitions.

As used in this Agreement, the following terms shall have the following meanings:

“2005 Warrants” means those warrants to purchase Common Stock listed on Annex A hereto.

“2005 Warrant Stock” means all shares of Common Stock which may be issued upon exercise of the rights represented by the 2005 Warrants.

“Arcapita Equity Letters” means, collectively, that certain Letter Agreement, dated as of December 6, 2011 between the Company and Arcapita Ventures I Limited, a Caymen Islands corporation (“Arcapita”), and that certain Letter Agreement, dated as of June 11, 2012 between the Company and Arcapita.

“Affiliate” means, (1) with respect to any Person, any of (a) a director, officer or stockholder holding 5% or more of the capital stock (on a fully diluted basis) of such Person, (b) a spouse, parent, sibling or descendant of such Person (or a spouse, parent, sibling or descendant of any director or officer of such Person) and (c) any other Person that, directly or indirectly through one or more intermediaries, controls, or is controlled by, or is under common control with, another Person or (2) in any event, any Person meeting the definition of “Affiliate” set forth in Rule 405 under the Securities Act. The term “control” includes, without limitation, the possession, directly or indirectly, of the power to direct the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise.

“Board” means the Board of Directors of the Company.

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“Charter” means the Third Amended and Restated Certificate of Incorporation of the Company, as amended from time to time.

“Commission” means the Securities and Exchange Commission or any other federal agency at the time administering the Securities Act.

“Common Stock” means the common stock, $0.001 par value per share, of the Company.

“Conversion True-Up Shares” has the meaning set forth in the Charter.

“December 2011 Notes” means the certain convertible promissory notes convertible into shares of Common Stock issued by the Company to certain purchasers pursuant to that certain note purchase agreement dated as of December 6, 2011 by and among the Company and the “Purchasers” named therein (as may be further amended from time to time, the “December 2011 Purchase Agreement”), together with any December 2011 Notes issued upon the transfer or division of, or in exchange or substitution for any such December 2011 Notes. For the avoidance of doubt, “December 2011 Notes” shall include only the Convertible Notes (as defined in the December 2011 Purchase Agreement) and not the Arcapita Note (as defined in the December 2011 Purchase Agreement).

“December 2011 Note Shares” means all shares of Common Stock which may be issued upon conversion of the December 2011 Notes pursuant to the terms thereof.

“Exchange Act” means the Securities Exchange Act of 1934, as amended, or any successor Federal statute, and the rules and regulations of the Commission promulgated thereunder, all as the same shall be in effect from time to time.

“FINRA” has the meaning set forth in Section 6(n).

“Holders” means Investors holding Registrable Shares or their transferees.

“Information” has the meaning set forth in Section 6(i).

“Inspectors” has the meaning set forth in Section 6(i).

“Investors” shall mean the parties to this Agreement who are designated as Investors as set forth on Schedule A to the Agreement.

“Investors Counsel” has the meaning set forth in Section 6(b).

“IPO” has the meaning set forth in the Charter.

“June 2011 Notes” means those certain convertible promissory notes convertible into shares of Common Stock issued by the Company to certain purchasers pursuant to that certain Note Purchase Agreement dated as of June 1, 2011 by and among the Company and the “Purchasers” named therein (as amended on June 14, 2011, and as may be further amended from time to time, the “June 2011 Purchase Agreement”), together with any June 2011 Notes issued

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upon the transfer or division of, or in exchange or substitution for any such June 2011 Notes. For the avoidance of doubt, “June 2011 Notes” shall include the Additional Notes (as defined in the June 2011 Purchase Agreement).

“June 2011 Note Shares” means all shares of Common Stock which may be issued upon conversion of the June 2011 Notes pursuant to the terms thereof.

“June 2012 Notes” means those certain convertible promissory notes convertible into shares of Common Stock issued by the Company to certain purchasers pursuant to the Purchase Agreement, together with any June 2012 Notes issued upon the transfer or division of, or in exchange or substitution for any such June 2012 Notes. For the avoidance of doubt, “June 2012 Notes” shall include only the Convertible Notes (as defined in the Purchase Agreement) and not the Arcapita Note (as defined in the Purchase Agreement).

“June 2012 Note Shares” means all shares of Common Stock which may be issued upon conversion of the June 2012 Notes pursuant to the terms thereof.

“Notes Shares” means, collectively, the December 2011 Note Shares, June 2011 Note Shares and the June 2012 Note Shares.

“Other Shares” means at any time those shares of Common Stock which do not constitute Primary Shares or Registrable Shares.

“Person” means any individual, partnership, corporation, group, trust or other legal entity.

“Preferred Stock” means the Series A Preferred Stock, the Series B Preferred Stock and any other series of the Company’s preferred stock.

“Primary Shares” means at any time the authorized, but unissued, shares of Common Stock and shares of Common Stock held by the Company in its treasury.

“Purchase Agreement” has the meaning set forth in the Recitals.

“Purchasers” has the meaning set forth in the Recitals.

“QPO” has the meaning set forth in the Charter.

“Records” has the meaning set forth in Section 6(i).

“Registrable Shares” means (i) the Common Stock issuable or issued upon the voluntary conversion on August 14, 2009 of the Company’s formerly outstanding Series A-1, A-2, A-3, B1, B-2 and B-3 Preferred Stock; (ii) the Common Stock issuable or issued upon conversion of the Preferred Stock, (iii) any True-Up Shares, (iv) any Note Shares, (v) the Common Stock issuable or issued pursuant to Section 2 of the Arcapita Equity Letters, (vi) any Warrant Stock, (vii) solely with respect to the rights granted in Sections 3 and 4, the 2005 Warrant Stock, and (viii) any other shares of Common Stock issued as a dividend or other distribution with respect to, or in exchange for or replacement of, any of the shares of Common Stock referred to in clauses (i),

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(ii), (iii), (iv), (v), (vi) or (vii). As to any particular Registrable Shares, once issued, such Registrable Shares shall cease to be Registrable Shares when (i) they have been registered under the Securities Act, the registration statement in connection therewith has been declared effective and they have been disposed of pursuant to such effective registration statement, or (ii) such Registrable Shares are held by an Investor (together with its affiliates) if (A) as reflected on the Company’s books and records, such Investor (together with its affiliates) holds less than 1% of the Company’s outstanding Common Stock (on an as-if-converted to Common Stock basis), (B) the Company has completed a QPO and (C) all shares of Common Stock issued or issuable upon conversion of such Registrable Shares held by and issuable to such Investor (and its affiliates) may be sold without limitation pursuant to Rule 144 during any ninety (90) day period.

“Rule 144” means Rule 144 promulgated under the Securities Act or any successor rule thereto or any complementary rule thereto (such as Rule 144A).

“Sale of the Company” has the meaning set forth in the Charter.

“Securities Act” means the Securities Act of 1933, as amended, or any successor Federal statute, and the rules and regulations of the Commission thereunder, all as the same shall be in effect from time to time.

“Series A Preferred Stock” means the Company’s Series A Preferred Stock, par value $0.001 per share.

“Series B Preferred Stock” has the meaning set forth in the Recitals.

“True-Up Shares” has the meaning set forth in the Charter.

“Warrants” means those certain warrants to initially subscribe for and purchase an aggregate of 1,496,107 shares of Common Stock issued by the Company to certain purchasers pursuant to a Subordinated Note and Warrant Purchase Agreement dated as of December 29, 2010 by and among the Company and the “Purchasers” named therein, together with any warrants issued upon the transfer or division of, or in exchange or substitution for any such Warrants.

“Warrant Stock” means all shares of Common Stock which may be issued upon the exercise of the rights represented by the Warrants.

Section 2. Demand Registration.

(a) At any time from the earlier of (i) six (6) months following the completion of an IPO or (ii) the third (3rd) anniversary of the date of this Agreement, if the Holders representing at least a majority of the Registrable Shares then outstanding (the “Initiating Holders”) shall state in writing that such Holders desire to sell Registrable Shares in the public securities markets and request the Company to effect the registration of Registrable Shares under the Securities Act, the Company shall promptly use its best efforts to effect the registration under the Securities Act of the Registrable Shares which the Company has been so requested to register by the Holders. For the avoidance of doubt, the Company shall not be required to register the sale or re-sale of any True-Up Shares or Conversion True-Up Shares in an IPO.

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(b) Notwithstanding anything contained in this Section 2 to the contrary, the Company shall not be obligated to effect any registration under the Securities Act except in accordance with the following provisions:

(i) The Company shall not be obligated to use its best efforts to file and cause to become effective (A) more than two (2) long-form registration statements initiated pursuant to Section 2(a) (other than those on form S-3 as set forth in Section 4) at the Company’s expense; (B) more than two (2) long-form registration statements initiated pursuant to Section 2(a) at the Holders’ expense; (C) any demand registration statement pursuant to Section 2(a) with an anticipated aggregate offering price of less than $10,000,000; nor (D) any registration statement during any period in which any other registration statement (other than on Form S-8 promulgated under the Securities Act or any successor form thereto) pursuant to which Primary Shares are to be or were sold has been filed and not withdrawn or has been declared effective within the prior one hundred eighty (180) days.

(ii) The Company may delay the filing or effectiveness of any registration statement for a period of up to ninety (90) days after the date of a request for registration pursuant to this Section 2 if at the time of such request the Company furnishes to the Holders requesting such registration statement pursuant to this Section 2, a certificate signed by the Chief Executive Officer of the Company stating that (i) the Company is engaged, or has fixed plans to engage within thirty (30) days of the time of such request, in a firm commitment underwritten public offering of Primary Shares in which the holders of Registrable Shares may include Registrable Shares pursuant to Section 3 or (ii) the Board has reasonably determined in its good faith judgment that it would be seriously detrimental to the Company and its stockholders for such registration statement to be filed, provided, however, that the Company may only delay the filing or effectiveness of a registration statement pursuant to this Section 2(b) for a total of one hundred and twenty (120) days after the date of a request for registration pursuant to this Section 2.

(iii) With respect to any registration pursuant to this Section 2, the Company shall give notice of such registration to all Holders that are not Initiating Holders and the holders of all Other Shares that are entitled to registration rights and the Company may include in such registration any Primary Shares or Other Shares and shall include all Registrable Shares that Holders that are not Initiating Holders request to be registered within 20 days of the mailing of the foregoing notice by the Company; provided, however, that if the managing underwriter advises the Company that the inclusion of all Registrable Shares, Primary Shares and/or Other Shares proposed to be included in such registration would interfere with the successful marketing (including pricing) of the Registrable Shares proposed to be included in such registration, then the number of Registrable Shares, Primary Shares and/or Other Shares proposed to be included in such registration shall be included in the following order:

(A) first, all the Registrable Shares that are issued or issuable upon conversion of the Series B Preferred Stock and any True-Up Shares (collectively, “Series B Registrable Shares”), subject to the last sentence of Section 2(a), requested to be included in such registration (or, if necessary, such Series B Registrable Shares pro rata among the Holders thereof based upon the number of Series B Registrable Shares requested to be registered by each such Holder);

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(B) second, all the Registrable Shares that are not Series B Registrable shares (“Non-Series B Registrable Shares”) requested to be included in such registration (or, if necessary, such Non-Series B Registrable Shares pro rata among the Holders thereof based upon the number of Non-Series B Registrable Shares requested to be registered by each such Holder);

(C) third, the Primary Shares; and

(D) fourth, the Other Shares that are entitled to registration rights requested to be included in such registration (or, if necessary, such Other Shares pro rata among the holders thereof based upon the number of Other Shares requested to be registered by each such holder).

(iv) If the Initiating Holders so elect, the offering of such Registrable Shares pursuant to such registration shall be in the form of an underwritten offering. The Initiating Holders shall, at their option, select one or more nationally prominent firms of investment bankers reasonably acceptable to the Company to act as the lead managing underwriter or underwriters in connection with such offering. In such event, the right of any Person to include such Person’s Registrable Shares or Other Shares in such registration shall be conditioned upon such Person’s participation in such underwriting. All Holders proposing to distribute their securities through such underwriting shall (together with the Company) enter into an underwriting agreement in customary form with the underwriter(s) selected for such underwriting.

Section 3. Piggyback Registration.

If the Company at any time proposes for any reason to register Primary Shares or Other Shares under the Securities Act (other than on Form S-4 or Form S-8 promulgated under the Securities Act or any successor forms thereto), it shall give written notice to the holders of Registrable Shares of its intention to so register such Primary Shares or Other Shares at least thirty (30) days before the initial filing of such registration statement and, upon the written request, delivered to the Company within twenty (20) days after delivery of any such notice by the Company, of the holders of Registrable Shares to include in such registration Registrable Shares (which request shall specify the number of Registrable Shares proposed to be included in such registration and shall state that such holder of Registrable Shares desires to sell such Registrable Shares in the public securities markets), the Company shall use its best efforts to cause all such Registrable Shares to be included in such registration on the same terms and conditions as the securities otherwise being sold in such registration; provided, however, that if the managing underwriter advises the Company that the inclusion of some or all Registrable Shares requested to be included in such registration would interfere with the successful marketing (including pricing) of the Primary Shares or Other Shares proposed to be registered by the Company, then the number of Primary Shares and Registrable Shares and Other Shares proposed to be included in such registration shall be included in the following order:

(i) first, the Primary Shares;

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(ii) second, the Series B Registrable Shares (or, if necessary, such Series B Registrable Shares will be cutback pro rata among the holders thereof based upon the number of Series B Registrable Shares requested to be registered by each such holder (or Series B Registrable Shares issued in respect thereof));

(iii) third, the Non-Series B Registrable Shares (or, if necessary, such Non-Series B Registrable Shares will be cutback pro rata among the holders thereof based upon the number of Non-Series B Registrable Shares requested to be registered by each such holder (or Non-Series B Registrable Shares issued in respect thereof), provided, however, that in no event will Registrable Shares be cut back pursuant to this clause (iii) or clause (ii) above to the point that Registrable Shares in aggregate constitute less than thirty five percent (35%) of the total number of shares registered in any registration under this Section 3); and

(iv) fourth, the Other Shares requested to be included in such registration (or, if necessary, such Other Shares pro rata among the holders thereof based upon the number of Other Shares requested to be registered by each such holder);

provided, however, that no Registrable Shares or Other Shares shall be required to be included in any registration pursuant to this Section 3 in connection with the Company’s initial public offering if the Company and the underwriters determine, in their sole discretion, not to include any shares other than Primary Shares.

Section 4. Registrations on Form S-3.

Anything contained in Section 2 to the contrary notwithstanding, at such time as the Company shall have qualified for the use of Form S-3 promulgated under the Securities Act or any successor form thereto, holders of the Registrable Shares then outstanding shall have the right to request in writing an unlimited number of registrations of Registrable Shares on Form S-3 or such successor form, which request or requests shall (i) specify the number of Registrable Shares intended to be sold or disposed of and the holders thereof, (ii) state the intended method of disposition of such Registrable Shares and (iii) relate to Registrable Shares having an aggregate offering price of at least $2,000,000. A requested registration on Form S-3 or any such successor form in compliance with this Section 4 shall not count as a registration statement initiated pursuant to Section 2, but shall otherwise be treated as a registration initiated pursuant to, and shall, except as otherwise expressly provided in this Section 4, be subject to Section 2; provided, however, that the Company shall not be obligated to (a) effect more than two registrations pursuant to this Section 3 in any twelve (12) month period or (b) keep effective at any one time more than one registration statement on Form S-3 with respect to Registrable Shares requested to be registered in accordance with this Section 4, and if the Company is requested to effect the registration of Registrable Shares on Form S-3 at a time when it is keeping such a registration statement effective, it may delay effecting such requested registration until it is no longer required in accordance with Section 6(a) hereof to keep effective the then effective registration statement on Form S-3, except the Company shall not be permitted to so delay any then effective registration on Form S-3 that is a “shelf” registration or a Rule 415 continuous offering.

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Section 5. Market “Stand-Off” Agreement.

(a) Solely in connection with an IPO (including an IPO pursuant to Section 2 hereof), if so requested by the underwriters, the Investors shall not sell publicly, make any short sale of, grant any option for the purchase of, or otherwise dispose publicly of, any capital stock of the Company (other than those shares of Common Stock included in such registration pursuant to Section 2, hereof) without the prior written consent of the Company, for a period designated by the Company in writing to the Investors, which period shall begin upon the effectiveness of the registration statement pursuant to which such IPO shall be made and shall not last more than one hundred and eighty (180) days (or such other period, not to exceed two hundred and ten (210) days, as may be requested by the Company or an underwriter to accommodate regulatory restrictions on (i) the publication or other distribution of research reports or (ii) analyst recommendations and opinions, including but not limited to the restrictions contained in FINRA Rule 2711(f)(4) or NYSE Rule 472(f) or any successor provisions or amendments thereto) after the effective date of such registration statement. The Company shall obtain the agreement of any person permitted to sell shares of stock in a registration to be bound by and to comply with this Section 5 as if such person was an Investor hereunder. In the event (a) the Company fails to attain an agreement from all of the Company’s directors and officers to be bound by and to comply with this Section 5 as if such person were an Investor hereunder or (b) the Company fails to attain such agreement from all holders of more than one percent (1%) of the Company’s outstanding capital stock, on a fully-diluted basis, the restrictions set forth in this Section 5 shall cease to apply to the Investors. The foregoing provisions of this Section 5 shall not apply to distributions or other transfers to Affiliates, partners, members, stockholders or other equity holders of an Investor, provided, that the recipient agrees to be similarly bound by this Section 5. Any discretionary waiver or termination of the restrictions of any or all of such agreements by the Company or the underwriters shall apply pro rata to all parties subject to such agreements, based on the number of shares subject to such agreements.

Section 6. Preparation and Filing.

If and whenever the Company is under an obligation pursuant to the provisions of this Agreement to effect the registration of any Registrable Shares, the Company shall, as expeditiously as practicable:

(a) use its best efforts to cause a registration statement that registers such Registrable Shares to become and remain effective for a period of ninety (90) days or until all of such Registrable Shares have been disposed of (if earlier);

(b) furnish, at least ten (10) business days before filing a registration statement that registers such Registrable Shares, a prospectus relating thereto or any amendments or supplements relating to such a registration statement or prospectus, to one counsel selected by the Investors whose reasonable fees and expenses (subject to the cap set forth in Section 7) shall be borne by the Company (the “Investors Counsel”), copies of all such documents proposed to be filed (it being understood that such ten (10) business-day period need not apply to successive drafts of the same document proposed to be filed so long as such successive drafts are supplied to the Investors Counsel in advance of the proposed filing by a period of time that is customary and reasonable under the circumstances);

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(c) prepare and file with the Commission such amendments and supplements to such registration statement and the prospectus used in connection therewith as may be necessary to keep such registration statement effective for at least a period of ninety (90) days or until all of such Registrable Shares have been disposed of (if earlier) and to comply with the provisions of the Securities Act with respect to the sale or other disposition of such Registrable Shares;

(d) notify in writing the Investors Counsel (i) of the receipt by the Company of any notification with respect to any comments by the Commission with respect to such registration statement or prospectus or any amendment or supplement thereto or any request by the Commission for the amending or supplementing thereof or for additional information with respect thereto, (ii) of the receipt by the Company of any notification with respect to the issuance by the Commission of any stop order suspending the effectiveness of such registration statement or prospectus or any amendment or supplement thereto or the initiation or threatening of any proceeding for that purpose and (iii) of the receipt by the Company of any notification with respect to the suspension of the qualification of such Registrable Shares for sale in any jurisdiction or the initiation or threatening of any proceeding for such purposes;

(e) use its best efforts to register or qualify such Registrable Shares under such other securities or blue sky laws of such jurisdictions as the Investors reasonably requests and do any and all other acts and things which may be reasonably necessary or advisable to enable the Investors to consummate the disposition in such jurisdictions of the Registrable Shares owned by the Investors; provided, however, that the Company will not be required to qualify generally to do business, subject itself to general taxation or consent to general service of process in any jurisdiction where it would not otherwise be required to do so but for this paragraph (e) or to provide any material undertaking or make any changes in its Bylaws or Certificate of Incorporation which the Board determines to be contrary to the best interests of the Company or to modify any of its contractual relationships then existing;

(f) furnish to the Investors holding such Registrable Shares such number of copies of a summary prospectus, if any, or other prospectus, including a preliminary prospectus, in conformity with the requirements of the Securities Act, and such other documents as the Investors may reasonably request in order to facilitate the public sale or other disposition of such Registrable Shares;

(g) without limiting subsection (e) above, use its best efforts to cause such Registrable Shares to be registered with or approved by such other governmental agencies or authorities as may be necessary by virtue of the business and operations of the Company to enable the Holders holding such Registrable Shares to consummate the disposition of such Registrable Shares;

(h) notify the Holders holding such Registrable Shares on a timely basis at any time when a prospectus relating to such Registrable Shares is required to be delivered under the Securities Act within the appropriate period mentioned in subparagraph (a) of this Section 6, of the happening of any event as a result of which the prospectus included in such registration statement, as then in effect, includes an untrue statement of a material fact or omits to state a material fact required to be stated therein or necessary to make the statements therein not

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misleading in light of the circumstances then existing and, at the request of the Investors, prepare and furnish to the Investors a reasonable number of copies of a supplement to or an amendment of such prospectus as may be necessary so that, as thereafter delivered to the offerees of such shares, such prospectus shall not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading in light of the circumstances then existing;

(i) subject to the execution of confidentiality agreements in form and substance satisfactory to the Company, make available upon reasonable notice and during normal business hours, for inspection by any Investor holding such Registrable Shares, any underwriter participating in any disposition pursuant to such registration statement and any attorney, accountant or other agent retained by the Investor or underwriter (collectively, the “Inspectors”), all pertinent financial and other records, pertinent corporate documents and properties of the Company (collectively, the “Records”), as shall be reasonably necessary to enable them to exercise their due diligence responsibility, and cause the Company’s officers, directors and employees to supply all information (together with the Records, the “Information”) reasonably requested by any such Inspector in connection with such registration statement. Any of the Information which the Company determines in good faith to be confidential, and of which determination the Inspectors are so notified, shall not be disclosed by the Inspectors unless (i) the disclosure of such Information is necessary to avoid or correct a misstatement or omission in the registration statement, (ii) the release of such Information is ordered pursuant to a subpoena or other order from a court of competent jurisdiction or (iii) such Information has been made generally available to the public; the Investors agree that they will, upon learning that disclosure of such Information is sought in a court of competent jurisdiction, give notice to the Company and allow the Company, at the Company’s expense, to undertake appropriate action to prevent disclosure of the Information deemed confidential;

(j) in the event of an underwritten offering pursuant to this Agreement, use its best efforts to obtain from its independent certified public accountants “comfort” letters in customary form and at customary times and covering matters of the type customarily covered by comfort letters at the request of the lead underwriter;

(k) in the event of an underwritten offering pursuant to this Agreement, use its best efforts to obtain from its counsel an opinion or opinions in customary form at the request of the lead underwriter;

(l) provide a transfer agent and registrar (which may be the same entity and which may be the Company) for such Registrable Shares;

(m) issue certificates evidencing such Registrable Shares to any underwriter (at the request of such underwriter) to which the Investors holding such Registrable Shares may sell shares in such offering;

(n) list such Registrable Shares on any national securities exchange on which any shares of the Common Stock are listed or, if the Common Stock is not listed on a national securities exchange, use its best efforts (or in the case of a registration under Section 3 hereof, reasonable best efforts) to qualify such Registrable Shares for inclusion on such national securities exchange as the holders of a majority of such Registrable Shares shall reasonably request;

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(o) otherwise use its best efforts to comply with all applicable rules and regulations of the Commission and make available to its securityholders, as soon as reasonably practicable, earnings statements (which need not be audited) covering a period of twelve (12) months beginning within three (3) months after the effective date of the registration statement, which earnings statements shall satisfy the provisions of Section 11(a) of the Securities Act;

(p) subject to all the other provisions of this Agreement, use its best efforts to take all other steps necessary to effect the registration of such Registrable Shares contemplated hereby; and

(q) in the event of any underwritten public offering, cooperate with the selling Holders, the underwriters participating in the offering and their counsel in any due diligence investigation reasonably requested by the selling Holders or the underwriters in connection therewith, and participate, to the extent reasonably requested by the managing underwriter for the offering or the selling Holder, in efforts to sell the Registrable Securities under the offering (including, without limitation, participating in “roadshow” meetings with prospective investors) that would be customary for underwritten primary offerings of a comparable amount of equity securities by the Company.

Each holder of the Registrable Shares, upon receipt of any notice from the Company of any event of the kind described in Section 6(h) hereof, shall forthwith discontinue disposition of the Registrable Shares pursuant to the registration statement covering such Registrable Shares until such holder’s receipt of the copies of the supplemented or amended prospectus contemplated by Section 6(h) hereof, and, if so directed by the Company, such holder shall deliver to the Company all copies, other than permanent file copies then in such holder’s possession, of the prospectus covering such Registrable Shares at the time of receipt of such notice.

Section 7. Expenses.

All expenses (other than stock transfer taxes and underwriting discounts and commissions relating to the Registrable Shares, as provided below) incurred by the Company in complying with Section 6, including, without limitation, all registration and filing fees (including all expenses incident to filing with the FINRA), fees and expenses of complying with securities and blue sky laws, printing expenses, fees and expenses of the Company’s counsel and accountants and reasonable fees and expenses of the Investors Counsel shall be paid by the Company (which fees and expenses of Investors Counsel shall not exceed one hundred thousand dollars ($100,000) with respect to a registration under Section 3 hereof); provided, however, that all underwriting discounts and selling commissions applicable to Primary Shares shall be borne by the Company; and provided, further, that all underwriting discounts and selling commissions applicable to Registrable Shares and Other Shares shall be borne by the holders selling such Registrable Shares and Other Shares, in proportion to the number of Registrable Shares and Other Shares, if any, sold thereby; and provided, further, that the Company shall not be obligated to pay fees or expenses of the Investors Counsel in connection with any registration requested by the Investors and later terminated, withdrawn or suspended at the request of the Investors (other than as a result of any material adverse change or event involving the Company).

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Section 8. Indemnification.

(a) In connection with any registration of any Registrable Shares under the Securities Act pursuant to this Agreement or otherwise, the Company shall indemnify and hold harmless the holders of Registrable Shares, each underwriter, broker or any other person acting on behalf of the holders of Registrable Shares and each other person, if any, who controls any of the foregoing persons within the meaning of the Securities Act against any losses, claims, damages or liabilities, joint or several (or actions in respect thereof), to which any of the foregoing persons may become subject under the Securities Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon an untrue statement or allegedly untrue statement of a material fact contained in the registration statement under which such Registrable Shares were registered under the Securities Act, any preliminary prospectus or final prospectus contained therein or otherwise filed with the Commission, any amendment or supplement thereto or any document incident to registration or qualification of any Registrable Shares, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading or, with respect to any prospectus, necessary to make the statements therein in light of the circumstances under which they were made not misleading, or arise out of or are based on any violation by the Company of the Securities Act or state securities or blue sky laws applicable to the Company and relating to action or inaction required of the Company in connection with such registration or qualification under such state securities or blue sky laws; and shall reimburse the holders of Registrable Shares, such underwriter, such broker or such other person acting on behalf of the holders of Registrable Shares and each such controlling person for any legal or other expenses reasonably incurred by any of them in connection with investigating or defending any such loss, claim, damage, liability or action; provided, however, that the Company shall not be liable in any such case to the extent that any such loss, claim, damage, liability or action (including any legal or other expenses incurred) arises out of or is based upon an untrue statement or allegedly untrue statement or omission or alleged omission made in said registration statement, preliminary prospectus, final prospectus, amendment, supplement or document incident to registration or qualification of any Registrable Shares in reliance upon and in conformity with written information furnished to the Company by the holders of Registrable Shares or their counsel or underwriter specifically for use in the preparation thereof.

(b) In connection with any registration of Registrable Shares under the Securities Act pursuant to this Agreement, each holder of Registrable Shares shall severally, and not jointly, indemnify and hold harmless (in the same manner and to the same extent as set forth in the preceding paragraph of this Section 8) the Company, each director of the Company, each officer of the Company who shall sign such registration statement, each underwriter, broker or other person acting on behalf of the holders of Registrable Shares and each person who controls any of the foregoing persons within the meaning of the Securities Act with respect to any statement or omission from such registration statement, any preliminary prospectus or final prospectus contained therein or otherwise filed with the Commission, any amendment or supplement thereto or any document incident to registration or qualification of any Registrable

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Shares, if such statement or omission was made in reliance upon and in conformity with written information furnished to the Company or such underwriter by such holder of Registrable Shares specifically for use in connection with the preparation of such registration statement, preliminary prospectus, final prospectus, amendment, supplement or document; provided, however, that the maximum amount of liability in respect of such indemnification shall be limited, in the case of each seller of Registrable Shares, to an amount equal to the net proceeds actually received by such Seller from the sale of Registrable Shares effected pursuant to such registration.

(c) Promptly after receipt by an indemnified party of notice of the commencement of any action involving a claim referred to in the preceding paragraphs of this Section 8, such indemnified party will, if a claim in respect thereof is made against an indemnifying party, give written notice to the latter of the commencement of such action. The failure of any indemnified party to notify an indemnifying party of any such action shall not (unless such failure shall have a material adverse effect on the indemnifying party) relieve the indemnifying party from any liability in respect of such action that it may have to such indemnified party on account of this Section 8. In case any such action is brought against an indemnified party, the indemnifying party will be entitled to participate in and to assume the defense thereof, jointly with any other indemnifying party similarly notified to the extent that it may wish, with counsel reasonably satisfactory to such indemnified party, and after notice from the indemnifying party to such indemnified party of its election so to assume the defense thereof, the indemnifying party shall not be responsible for any legal or other expenses subsequently incurred by the indemnified party in connection with the defense thereof; provided, however, that if any indemnified party shall have reasonably concluded that there may be one or more legal or equitable defenses available to such indemnified party which are additional to or conflict with those available to the indemnifying party, or that such claim or litigation involves or could have an effect upon matters beyond the scope of the indemnity agreement provided in this Section 8, the indemnifying party shall not have the right to assume the defense of such action on behalf of such indemnified party (but shall have the right to participate therein with counsel of its choice) and such indemnifying party shall reimburse such indemnified party and any person controlling such indemnified party for that portion of the fees and expenses of any counsel retained by the indemnified party which is reasonably related to the matters covered by the indemnity agreement provided in this Section 8. If the indemnifying party is not entitled to, or elects not to, assume the defense of a claim, it will not be obligated to pay the fees and expenses of more than one counsel with respect to such claim.

(d) If the indemnification provided for in this Section 8 is held by a court of competent jurisdiction to be unavailable to an indemnified party with respect to any loss, claim, damage, liability or action referred to herein, then the indemnifying party, in lieu of indemnifying such indemnified party hereunder, shall contribute to the amounts paid or payable by such indemnified party as a result of such loss, claim, damage, liability or action in such proportion as is appropriate to reflect the relative fault of the indemnifying party on the one hand and of the indemnified party on the other in connection with the statements or omissions which resulted in such loss, claim, damage, liability or action as well as any other relevant equitable considerations. The relative fault of the indemnifying party and of the indemnified party shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the indemnifying party or by the indemnified party and the parties’

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relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission. The parties agree that it would not be just and equitable if contribution pursuant hereto were determined by pro rata allocation or by any other method of allocation which does not take account of the equitable considerations referred to herein. No person guilty of fraudulent misrepresentation shall be entitled to contribution from any person.

(e) The obligations of the Company and Holders under this Section 8 shall survive completion of any offering of Registrable Shares in a registration statement and the termination of this Agreement. No indemnifying party, in the defense of any such claim or litigation, shall, except with the consent of each indemnified party, consent to entry of any judgment or enter into any settlement which does not include as an unconditional term thereof the giving by the claimant or plaintiff to such indemnified party of a release from all liability in respect to such claim or litigation.

Section 9. Underwriting Agreement.

Notwithstanding the provisions of Sections 5, 6, 7 and 8, to the extent that the Company and the Investors shall enter into an underwriting or similar agreement, which agreement contains provisions covering one or more issues addressed in such Sections, the provisions contained in such agreement addressing such issue or issues shall control. Each Holder further agrees to execute such customary lock-up agreements as may be reasonably requested by the underwriters in connection with an underwritten offering.

Section 10. Information by Holders.

Each Investor shall furnish to the Company such written information regarding such Investor and the distribution proposed by such Investor as the Company may reasonably request in writing and as shall be reasonably required in connection with any registration, qualification or compliance referred to in this Agreement.

Section 11. Exchange Act Compliance.

With a view to making available to the Holders the benefits of certain rules and regulations of the Commission which may permit the sale of the Registrable Securities to the public without registration, the Company agrees to use its best efforts to:

(a) make and keep public information available, as those terms are understood and defined in Commission Rule 144 or any similar or analogous rule promulgated under the Securities Act, at all times after the effective date of the IPO;

(b) take such action, including the voluntary registration of its Common Stock under Section 12 of the Exchange Act, as is necessary to enable the Holders to utilize Form S-3 for the sale of their Registrable Securities, such action to be taken as soon as practicable after the end of the fiscal year in which the first registration statement filed by the Company for the offering of its securities to the general public is declared effective;

(c) file with the Commission, in a timely manner, all reports and other documents required of the Company under the Exchange Act; and

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(d) furnish to such Holder forthwith upon request: (i) a written statement by the Company as to its compliance with the reporting requirements of said Rule 144 (at any time after ninety (90) days after the effective date of the first registration statement filed by the Company), of the Securities Act, and of the Exchange Act (at any time after it has become subject to such reporting requirements); (ii) a copy of the most recent annual or quarterly report of the Company and such other forms and reports filed by the Company with the Commission; and (iii) such other reports and documents as a Holder may reasonably request in availing itself of any rule or regulation of the Commission allowing it to sell any such securities without registration.

Section 12. No Conflict of Rights.

Without the consent of the holders of at least a majority of the Registrable Shares then outstanding which are issued or issuable upon conversion of Preferred Stock, the Company shall not, after the date hereof, grant any registration rights that are not subordinate to or that conflict with or impair the registration rights granted hereby.

Section 13. Termination.

This Agreement shall terminate and be of no further force or effect (except as to such provisions which expressly survive the termination of the Agreement) upon the earlier of (a) the seventh (7th) anniversary of the Company’s first QPO or (b) as to each Holder the date upon which such Holder ceases to hold Registrable Shares.

Section 14. Successors and Assigns.

This Agreement shall bind and inure to the benefit of the Company, the Investors and, subject to Section 15, the respective successors and assigns of the Company and the Investors.

Section 15. Assignment.

An Investor may assign its rights hereunder to an Affiliate of such Investor or to any other purchaser or transferee of (a) at least 333,333 (or, if less, all) of such Investor’s Registrable Shares (as adjusted for stock splits, dividends, recapitalizations and the like) or (b) at least $1,000,000 principal amount of the Notes; provided, however, that (i) such purchaser or transferee may not be a competitor of the Company; (ii) such purchaser or transferee shall, as a condition to the effectiveness of such assignment, be required to execute a counterpart to this Agreement agreeing to be treated as an “Investor” hereunder; (iii) such purchaser or transferee shall be subject to the restrictions contained in this Agreement as if such purchaser or transferee was originally included in the definition of Investors herein and had originally been a party hereto; and (iv) such assignment must be made in compliance with Article II of the Settlement Agreement and First Amendment to Cross License Agreement dated as of September 21, 2007 by and between Cabot Corporation and the Company.

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Section 16. Entire Agreement.

This Agreement, and the other writings referred to herein or therein or delivered pursuant hereto or thereto, contains the entire agreement between the Investors and the Company with respect to the subject matter hereof and supersede all prior and contemporaneous arrangements or understandings with respect thereto.

Section 17. Notices.

All notices, requests, consents and other communications hereunder to any party shall be deemed to be sufficient if contained in a written instrument delivered in person or sent by telecopy, nationally-recognized overnight courier or first class registered or certified mail, return receipt requested, postage prepaid, addressed to such party at the address set forth below or such other address as may hereafter be designated in writing by such party to the other parties:

(i) If to the Company:

• Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, Massachusetts 01532

Telephone:	(508) 691-1111
Facsimile:	(508) 691-1200
Attention:	Chief Financial Officer

• with a copy to:

Edwards Angell Palmer & Dodge, LLP

111 Huntington Avenue

Boston, MA 02199

Telephone:	(617) 951-2207
Facsimile:	(888) 325-9513
Attention:	Christopher W. Nelson, Esq.

(ii) If to any Investor:

• To their address set forth on Schedule A hereto.

All such notices, requests, consents and other communications shall be deemed to have been delivered (a) in the case of personal delivery or delivery by telecopy, on the date of such delivery, (b) in the case of dispatch by nationally-recognized overnight courier, on the next business day following such dispatch and (c) in the case of mailing, on the third business day after the posting thereof.

Section 18. Modifications; Amendments; Waivers.

The terms and provisions of this Agreement may not be modified or amended, nor may any provision be waived, except pursuant to a writing signed by the Company and the holders of at least a majority of the Registrable Shares then outstanding which are issued or issuable upon conversion of the Preferred Stock, provided, however, that at any time when shares of Series B Preferred Stock are outstanding, no amendment or waiver of Section 2(b)(iii) or Section 3 hereof,

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which would change the priority of the Series B Registrable Shares relative to the Non-Series B Registrable Shares with respect to cut-backs, may be made without the written consent of the holders of two-thirds of the then outstanding shares of the Series B Preferred Stock, provided, further, that at any time when any Warrants or Warrant Stock are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the Warrants or Warrant Stock, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding Warrants and Warrant Stock; provided, further, that at any time when any June 2011 Notes or June 2011 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the June 2011 Notes or June 2011 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding June 2011 Notes and June 2011 Note Shares; provided, further, that at any time when any December 2011 Notes or December 2011 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the December 2011 Notes or December 2011 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding December 2011 Notes and December 2011 Note Shares; provided, further, that at any time when any June 2012 Notes or June 2012 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the June 2012 Notes or June 2012 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding June 2012 Notes or June 2012 Note Shares.

Section 19. Counterparts; Facsimile Signatures.

This Agreement may be executed in any number of counterparts, including by an omnibus signature page that also constitutes the signature page to other agreements, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Agreement may be executed by facsimile or by electronic or PDF file.

Section 20. Headings.

The headings of the various sections of this Agreement have been inserted for convenience of reference only and shall not be deemed to be a part of this Agreement.

Section 21. Aggregation of Stock.

All shares of Registrable Shares held or acquired by Affiliates shall be aggregated together for the purpose of determining the availability of any rights under this Agreement and such Affiliated persons may apportion such rights as among themselves in any manner they deem appropriate.

Section 22. Additional Investors.

Notwithstanding anything to the contrary contained herein, if the Company issues additional June 2012 Notes after the date hereof, pursuant to the Purchase Agreement any

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purchaser of such June 2012 Notes may become a party to this Agreement by executing and delivering an additional counterpart signature page to this Agreement, and thereafter shall be deemed an “Investor” for all purposes hereunder. No action or consent by the Investors shall be required for such joinder to this Agreement by such additional Investor, so long as such additional Investor has agreed in writing to be bound by all of the obligations as an “Investor” hereunder.

Section 23. Governing Law.

THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF DELAWARE APPLICABLE TO CONTRACTS MADE AND TO BE PERFORMED WHOLLY THEREIN.

[THIS SPACE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ARCAPITA VENTURES I LIMITED
By:	/s/ John Huntz
Name:	John Huntz
Title:	Executive Director

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ARGONAUT VENTURES I, LLC
By:	Argonaut Private Equity, LLC, its Manager
By:	/s/ Steve R. Mitchell
Name:	Steve R. Mitchell
Title:	Managing Director

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

BASF VENTURE CAPITAL GMBH
By:	/s/ Dirk Nachtigal
Name:	Dirk Nachtigal
Title:	Managing Director

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

CONTRA COSTA CAPITAL, LLC
By:	/s/ Alexander Weiss
Name:	Alexander Weiss
Title:	Vice President

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

RESERVOIR CAPITAL PARTNERS, L.P.
By:	RCP GP, LLC
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer
RESERVOIR CAPITAL MASTER FUND, L.P.
By:	Reservoir Capital Group, L.L.C.
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ROCKPORT CAPITAL PARTNERS II, L.P.
By:	RockPort Capital II, L.L.C.
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing Member
ROCKPORT CAPITAL PARTNERS, L.P.
By:	RockPort Capital, L.L.C.
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing Member
RP CO-INVESTMENT FUND I, L.P.
By:	RP Co-Investments Fund I, GP, LLC
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing Member
ROCKPORT SII, LLC
By:	RockPort SGII, LLC
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing Member

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

TENAYA CAPITAL IV-C, L.P.
By: Tenaya Capital IV GP L.P., its General Partner
By: Tenaya Capital IV GP LLC, its General Partner
By:	/s/ Dave Markland
	Dave Markland
	Attorney-In-Fact
TENAYA CAPITAL IV-P, L.P.
By: Tenaya Capital IV GP L.P., its General Partner
By: Tenaya Capital IV GP LLC, its General Partner
By:	/s/ Dave Markland
	Dave Markland
	Attorney-In-Fact
TENAYA CAPITAL IV, L.P.
By: Tenaya Capital IV Annex GP LLC, its General Partner
By:	/s/ Dave Markland
	Dave Markland
	Attorney-In-Fact

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY SELECT PORTFOLIOS: ENVIRONMENT AND ALTERNATIVE ENERGY PORTFOLIO
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
FIDELITY PURITAN TRUST: FIDELITY PURITAN FUND
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
VARIABLE INSURANCE PRODUCTS FUND III: BALANCED PORTFOLIO
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
FIDELITY SECURITIES FUND: FIDELITY DIVIDEND GROWTH FUND
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
FIDELITY ADVISOR SERIES I: FIDELITY ADVISOR DIVIDEND GROWTH FUND
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY MATERIALS CENTRAL FUND
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
VARIABLE INSURANCE PRODUCTS FUND IV: MATERIALS PORTFOLIO
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
FIDELITY SELECT PORTFOLIOS: MATERIALS
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
FIDELITY SELECT PORTFOLIOS: INDUSTRIALS PORTFOLIO
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY ADVISOR SERIES VII: FIDELITY
ADVISOR INDUSTRIALS FUND
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
VARIABLE INSURANCE PRODUCTS
FUND IV: INDUSTRIALS PORTFOLIO
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer
FIDELITY CENTRAL INVESTMENT
PORTFOLIOS LLC: FIDELITY INDUSTRIALS
CENTRAL FUND
By:	/s/ Kenneth Robins
Name:	Kenneth Robins
Title:	Treasurer

Signature Page to Sixth Amended and Restated Registration Rights Agreement

IN WITNESS WHEREOF, the parties hereto have executed this Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

NICHIAS CORPORATION
By:	/s/ Kunihiko Yano
Name:	Mr. Kunihiko Yano
Title:	President and Chief Executive Officer

Signature Page to Sixth Amended and Restated Registration Rights Agreement

Annex A

2005 Warrants

Warrant Holder	Issue Date	Expiration Date	Number of Shares
Heller Financial Leasing, Inc.	20-Oct-04	20-Oct-14		56
Atel Ventures, Inc.	28-Oct-04	28-Oct-14		28
Massachusetts Development Finance Agency	12-Jan-05	12-Jan-15		25
Reservoir Capital Partners, L.P.	24-Feb-05	24-Feb-13		198
Reservoir Capital Master Fund, L.P.	24-Feb-05	24-Feb-13		26
Reservoir Capital Partners, L.P.	23-Mar-05	23-Mar-13		128
Reservoir Capital Master Fund, L.P.	23-Mar-05	23-Mar-13		17
RP Co-Investment Fund I, L.P.	23-Mar-05	23-Mar-13		15
RockPort Capital Partners, L.P.	23-Mar-05	23-Mar-13		14
Tenaya Capital IV-P, L.P.	23-Mar-05	23-Mar-13		6
Tenaya Capital IV-C, L.P.	23-Mar-05	23-Mar-13		6
Sun Young Park	23-Mar-05	23-Mar-13		6
Aerogel Korea Co., Ltd.	23-Mar-05	23-Mar-13		5
Lehman Brothers Venture Capital Partners II, L.P.	23-Mar-05	23-Mar-13		3
Tenaya Capital IV, L.P.	23-Mar-05	23-Mar-13		3
Lehman Brother P.A. LLC	23-Mar-05	23-Mar-13		2
Thomas L. Cunningham	23-Mar-05	23-Mar-13		1
Dalsuk Youn	23-Mar-05	23-Mar-13		1
Lehman Brothers Partnerhsip Account 2000/2001, L.P.	23-Mar-05	23-Mar-13		1
J. Christopher Young	23-Mar-05	23-Mar-13		1
James P. Manzi	23-Mar-05	23-Mar-13		1
Heller Financial Leasing, Inc.	23-Mar-05	23-Mar-13		1
Soo Young & Myung Sook Chung	23-Mar-05	23-Mar-13		1
Star Faith Holdings Ltd.	23-Mar-05	23-Mar-13		1
Nancy L. and F. Lester Fraser	23-Mar-05	23-Mar-13		1
Protos, LLC	23-Mar-05	23-Mar-13		1
Michael H. Koegler	23-Mar-05	23-Mar-13		1
Lehman Brothers Offshore Partnership Account 2000/2001, L.P.	23-Mar-05	23-Mar-13		1
Dong W. Cho	23-Mar-05	23-Mar-13		1
Charles C. Cunningham, Jr.	23-Mar-05	23-Mar-13		1
Jonathan F. P. Rose	23-Mar-05	23-Mar-13		1
Bonwan Koo	23-Mar-05	23-Mar-13		1
Sung Choi	23-Mar-05	23-Mar-13		1
Melissa D. Kaplan	23-Mar-05	23-Mar-13		1
Maricamp, LLC	23-Mar-05	23-Mar-13		1
Richard and Kristina Han	23-Mar-05	23-Mar-13		1

Signature Page to Sixth Amended and Restated Registration Rights Agreement

Warrant Holder	Issue Date	Expiration Date	Number of Shares
Paul and Marie Jo	23-Mar-05	23-Mar-13		1
Edward Lamont	23-Mar-05	23-Mar-13		1
Douglas A. Muller	23-Mar-05	23-Mar-13		1
Key-Hyup Kim	23-Mar-05	23-Mar-13		1
Ariel Flores 1999 Trust	23-Mar-05	23-Mar-13		1
Jean-Paul Benveniste	23-Mar-05	23-Mar-13		1
Fred Smithson	23-Mar-05	23-Mar-13		1
Jamie McCourt	23-Mar-05	23-Mar-13		1
Roger J. Herz	23-Mar-05	23-Mar-13		1
Robert D. Batting	23-Mar-05	23-Mar-13		1
James J. Childress	23-Mar-05	23-Mar-13		1
Richard M. C. Glenn III	23-Mar-05	23-Mar-13		1

Signature Page to Sixth Amended and Restated Registration Rights Agreement

ASPEN AEROGELS, INC.

AMENDMENT NO. 1 TO

SIXTH AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

This Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement (this “Amendment”) is entered into as of September 26, 2012, by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Investors set forth on the signature pages hereto, constituting the holders of at least a majority of the Registrable Shares currently outstanding which are issued or issuable upon conversion of the Preferred Stock (the “Requisite Holders”). Capitalized terms used herein but not defined shall have the meanings ascribed to them in the Sixth Amended and Restated Registration Rights Agreement of the Company dated June 11, 2012 (the “Registration Rights Agreement”).

WHEREAS, the Company and the Requisite Holders wish to amend the Registration Rights Agreement in accordance with Section 18 thereof.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. Recital “I” of the Registration Rights Agreement is hereby deleted in its entirety and the following new Recital “I” is substituted in lieu thereof:

“Certain Investors (the “Purchasers”) will purchase June 2012 Notes (defined below) pursuant to a Note Purchase Agreement, dated as of June 11, 2012 as amended by Amendment No. 1 to Note Purchase Agreement dated September 26, 2012, by and among the Company and the Purchasers (as may be amended from time to time, the “Purchase Agreement”).

2. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Arcapita Equity Letters” in its entirety and the following new definition of “Arcapita Equity Letters” is substituted in lieu thereof:

“Arcapita Equity Letters” means, collectively, that certain Letter Agreement, dated as of December 6, 2011 between the Company and Arcapita Ventures I Limited, a Cayman Islands corporation (“Arcapita”), that certain Letter Agreement, dated as of June 11, 2012, between the Company and Arcapita, and that certain Letter Agreement, dated as of September 26, 2012, between the Company and Arcapita.

3. Except to the extent amended hereby, all of the terms, provisions and conditions of the Registration Rights Agreement are hereby ratified and confirmed and shall remain in full force and effect.

4. This Amendment may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Amendment may be executed by facsimile or by electronic or PDF file.

[Signature pages to follow]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ARCAPITA VENTURES I LIMITED
By:	/s/ John Huntz
Name:	John Huntz
Title:	Executive Director

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ARGONAUT VENTURES I, LLC
By: Argonaut Private Equity, LLC, its Manager
By:	/s/ Steve R. Mitchell
Name:	Steve R. Mitchell
Title:	Managing Director

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

CONTRA COSTA CAPITAL, LLC
By:	/s/ Alexander Weiss
Name:	Alexander Weiss
Title:	Vice President

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

RESERVOIR CAPITAL PARTNERS, L.P.
By:	RCP GP, LLC
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer
RESERVOIR CAPITAL MASTER FUND, L.P.
By:	Reservoir Capital Group, L.L.C.
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ROCKPORT CAPITAL PARTNERS II, L.P.
By:	RockPort Capital II, L.L.C.
Its:	General Partner
By:	/s/ Janet James
Name:	Janet James
Title:	Managing Member
ROCKPORT CAPITAL PARTNERS, L.P.
By:	RockPort Capital, L.L.C.
Its:	General Partner
By:	/s/ Janet James
Name:	Janet James
Title:	Managing Member
RP CO-INVESTMENT FUND I, L.P.
By:	RP Co-Investments Fund I, GP, LLC
Its:	General Partner
By:	/s/ Janet James
Name:	Janet James
Title:	Managing Member
ROCKPORT SII, LLC
By:	RockPort SGII, LLC
Its:	General Partner
By:	/s/ Janet James
Name:	Janet James
Title:	Managing Member

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

TENAYA CAPITAL IV-C, L.P.
By: Tenaya Capital IV GP L.P., its General Partner
By: Tenaya Capital IV GP LLC, its General Partner
By:	/s/ Dave Markland
	Dave Markland
	Attorney-In-Fact
TENAYA CAPITAL IV-P, L.P.
By: Tenaya Capital IV GP L.P., its General Partner
By: Tenaya Capital IV GP LLC, its General Partner
By:	/s/ Dave Markland
	Dave Markland
	Attorney-In-Fact
TENAYA CAPITAL IV, L.P.
By: Tenaya Capital IV Annex GP LLC, its General Partner
By:	/s/ Dave Markland
	Dave Markland
	Attorney-In-Fact

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY SELECT PORTFOLIOS: ENVIRONMENT AND ALTERNATIVE ENERGY PORTFOLIO
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
FIDELITY PURITAN TRUST: FIDELITY PURITAN FUND
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND III: BALANCED PORTFOLIO
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
FIDELITY SECURITIES FUND: FIDELITY DIVIDEND GROWTH FUND
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
FIDELITY ADVISOR SERIES I: FIDELITY ADVISOR DIVIDEND GROWTH FUND
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY MATERIALS CENTRAL FUND
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND IV: MATERIALS PORTFOLIO
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
FIDELITY SELECT PORTFOLIOS: MATERIALS
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
FIDELITY SELECT PORTFOLIOS: INDUSTRIALS PORTFOLIO
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY ADVISOR SERIES VII: FIDELITY ADVISOR INDUSTRIALS FUND
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND IV: INDUSTRIALS PORTFOLIO
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer
FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY INDUSTRIALS CENTRAL FUND
By:	/s/ Joseph Zambello
Name:	Joseph Zambello
Title:	Deputy Treasurer

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 1 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

NICHIAS CORPORATION
By:	/s/ Kunihiko Yano
Name:	Mr. Kunihiko Yano
Title:	President and Chief Executive Officer

[Signature Page to Amend. No. 1 to Sixth Amended and Restated Registration Rights Agreement]

EXECUTION COPY

ASPEN AEROGELS, INC.

AMENDMENT NO. 2 TO

SIXTH AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

This Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement (this “Amendment”) is entered into as of March 28, 2013, by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Investors set forth on the signature pages hereto, constituting the holders of at least a majority of the Registrable Shares currently outstanding which are issued or issuable upon conversion of the Preferred Stock (the “Requisite Holders”). Capitalized terms used herein but not defined shall have the meanings ascribed to them in the Sixth Amended and Restated Registration Rights Agreement of the Company dated June 11, 2012, as amended by Amendment No. 1 dated September 26, 2012 (the “Registration Rights Agreement”).

WHEREAS, the Company and the Requisite Holders wish to amend the Registration Rights Agreement in accordance with Section 18 thereof.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. Recitals “I” through “L” of the Registration Rights Agreement are hereby deleted in their entirety and the following new Recitals are substituted in lieu thereof:

I. Certain Investors (the “June 2012 Purchasers”) purchased June 2012 Notes (defined below) pursuant to a Note Purchase Agreement, dated as of June 11, 2012, as amended by Amendment No. 1 to Note Purchase Agreement dated September 26, 2012, by and among the Company and the June 2012 Purchasers (as may be amended from time to time, the “June 2012 Purchase Agreement”).

J. Certain Investors (the “March 2013 Purchasers” and together with the June 2012 Purchasers the “Purchasers”) will purchase March 2013 Notes (defined below) and Series C Warrants (defined below) pursuant to a Note and Warrant Purchase Agreement, dated as of March 28, 2013, by and among the Company and the March 2013 Purchasers (as may be amended from time to time, the “March 2013 Purchase Agreement”).

K. The Company and the Majority Holders under the Fifth Amended Agreement, together with the Purchasers, desire to amend and restate the Fifth Amended Agreement by deleting it in its entirety and replacing it with this Agreement.

L. The Company and the Investors desire to enter into this Agreement for the purpose of establishing the registration rights of the Common Stock.

M. The execution and delivery of this Agreement was a condition to the June 2012 Purchasers’ purchase of June 2012 Notes pursuant to the June 2012 Purchase Agreement and is a condition to the March 2013 Purchasers’ purchase of March 2013 Notes pursuant to the March 2013 Purchase Agreement.

2. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Purchase Agreement” in its entirety, and each reference to “Purchase Agreement” throughout the Registration Rights Agreement shall be deleted and replaced by the words “June 2012 Purchase Agreement.”

3. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Arcapita Equity Letters” in its entirety and the following new definition of “Arcapita Equity Letters” is substituted in lieu thereof:

“Arcapita Equity Letters” means, collectively, that certain Letter Agreement, dated as of December 6, 2011, between the Company and Arcapita Ventures I Limited, a Cayman Islands corporation (“Arcapita”), that certain Letter Agreement, dated as of June 11, 2012, between the Company and Arcapita, that certain Letter Agreement, dated as of September 26, 2012, between the Company and Arcapita and that certain Letter Agreement, dated as of January 9, 2013, between the Company and Arcapita.

4. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Charter” in its entirety and the following new definition of “Charter” is substituted in lieu thereof:

“Charter” means the Fourth Amended and Restated Certificate of Incorporation of the Company, as amended from time to time.

5. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Common Stock” in its entirety and the following new definition of “Common Stock” is substituted in lieu thereof:

“Common Stock” means the common stock, $0.00001 par value per share, of the Company.

6. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Note Shares” in its entirety and the following new definition of “Note Shares” is substituted in lieu thereof:

“Note Shares” means, collectively, the June 2011 Note Shares, December 2011 Note Shares, June 2012 Note Shares and March 2013 Note Shares.

7. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Preferred Stock” in its entirety and the following new definition of “Preferred Stock” is substituted in lieu thereof:

“Preferred Stock” means the Series A Preferred Stock, the Series B Preferred Stock, the Series C Preferred Stock and any other series of the Company’s preferred stock (including any Series C Warrant Stock).

8. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Registrable Shares” in its entirety and the following new definition of “Registrable Shares” is substituted in lieu thereof:

“Registrable Shares” means (i) the Common Stock issuable or issued upon the voluntary conversion on August 14, 2009, of the Company’s formerly outstanding Series A-1, A-2, A-3, B1, B-2 and B-3 Preferred Stock; (ii) the Common Stock issuable or issued upon conversion of the Preferred Stock, (iii) any True-Up Shares, (iv) any Note Shares, (v) the Common Stock issuable or issued pursuant to Section 2 of the Arcapita Equity Letters, (vi) any Warrant Stock, (vii) solely with respect to the rights granted in Sections 3 and 4, the 2005 Warrant Stock, (viii) any Series C Warrant Stock and (ix) any other shares of Common Stock issued as a dividend or other distribution with respect to, or in exchange for or replacement of, any of the shares of Common Stock referred to in clauses (i), (ii), (iii), (iv), (v), (vi) or (viii). As to any particular Registrable Shares, once issued, such Registrable Shares shall cease to be Registrable Shares when (i) they have been registered under the Securities Act, the registration statement in connection therewith has been declared effective and they have been disposed of pursuant to such effective registration statement, or (ii) such Registrable Shares are held by an Investor (together with its affiliates) if (A) as reflected on the Company’s books and records, such Investor (together with its affiliates) holds less than 1% of the Company’s outstanding Common Stock (on an as-if-converted to Common Stock basis), (B) the Company has completed a QPO and (C) all shares of Common Stock issued or issuable upon conversion of such Registrable Shares held by and issuable to such Investor (and its affiliates) may be sold without limitation pursuant to Rule 144 during any ninety (90) day period.

9. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Series A Preferred Stock” in its entirety and the following new definition of “Series A Preferred Stock” is substituted in lieu thereof:

“Series A Preferred Stock” means the Company’s Series A Preferred Stock, par value $0.00001 per share.

10. Section 1 of the Registration Rights Agreement is hereby amended by deleting the definition of “Series B Preferred Stock” in its entirety and the following new definition of “Series B Preferred Stock” is substituted in lieu thereof:

“Series B Preferred Stock” means the Company’s Series B Preferred Stock, par value $0.00001 per share.

11. Section 1 of the Registration Rights Agreement is hereby amended by adding six new definitions as follows:

“March 2013 Notes” means those certain convertible promissory notes convertible into shares of Common Stock issued by the Company to certain purchasers pursuant to the March 2013 Purchase Agreement, together with any March 2013 Notes issued upon the transfer or division of, or in exchange or substitution for any such March 2013 Notes. For the avoidance of doubt, “March 2013 Notes” shall include only the Convertible Notes (as defined in the March 2013 Purchase Agreement) and not the Arcapita Note (as defined in the March 2013 Purchase Agreement).

“March 2013 Note Shares” means all shares of Common Stock which may be issued upon conversion of the March 2013 Notes pursuant to the terms thereof.

“Notes” means, collectively, the June 2011 Notes, December 2011 Notes, June 2012 Notes and March 2013 Notes.

“Series C Preferred Stock” means the Company’s Series C Preferred Stock, par value $0.00001 per share.

“Series C Warrants” means those certain warrants to initially subscribe for and purchase an aggregate of 870,181,654 shares of Series C Preferred Stock issued by the Company to the March 2013 Purchasers pursuant to the March 2013 Purchase Agreement, together with any warrants issued upon the transfer or division of, or in exchange or substitution for any such Series C Warrants.

“Series C Warrant Stock” means all shares of Series C Preferred Stock which may be issued upon the exercise of the rights represented by the Series C Warrants.

12. Section 2(b)(iii) of the Registration Rights Agreement is hereby amended by deleting subsections (A) through (D) in their entirety and the following new subsections are substituted in lieu thereof:

(A) first, all the Registrable Shares that are issued or issuable upon conversion of the Series C Preferred Stock (including any Series C Warrant Stock, collectively, “Series C Registrable Shares”) or March 2013 Note Shares (“March 2013 Note Registrable Shares”) requested to be included in such registration (or, if necessary, such Series C Registrable Shares and March 2013 Note Registrable Shares pro rata among the Holders thereof based upon the aggregate number of Series C Registrable Shares and March 2013 Note Registrable Shares requested to be registered by each such Holder);

(B) second, all the Registrable Shares that are issued or issuable upon conversion of the Series B Preferred Stock and any True-Up Shares (collectively, “Series B Registrable Shares”), subject to the last sentence of Section 2(a), requested to be included in such registration (or, if necessary, such Series B Registrable Shares pro rata among the Holders thereof based upon the number of Series B Registrable Shares requested to be registered by each such Holder);

(C) third, all the Registrable Shares that are not Series C Registrable Shares, Series B Registrable Shares or March 2013 Note Registrable Shares (“Non-Series B/C March 2013 Note Registrable Shares”) requested to be included in such registration (or, if necessary, such Non-Series B/C March 2013 Note Registrable Shares pro rata among the Holders thereof based upon the number of Non-Series B/C March 2013 Note Registrable Shares requested to be registered by each such Holder);

(D) fourth, the Primary Shares; and

(E) fifth, the Other Shares that are entitled to registration rights requested to be included in such registration (or, if necessary, such Other Shares pro rata among the holders thereof based upon the number of Other Shares requested to be registered by each such holder).

13. Section 3 of the Registration Rights Agreement is hereby amended by deleting subsections (ii) through (iv) in their entirety and the following new subsections are substituted in lieu thereof:

(ii) second, the Series C Registrable Shares and March 2013 Note Registrable Shares (or, if necessary, such Series C Registrable Shares and March 2013 Note Registrable Shares will be cut back pro rata among the holders thereof based upon the aggregate number of Series C Registrable Shares and March 2013 Note Registrable Shares requested to be registered by each such holder (or Series C Registrable Shares or March 2013 Note Registrable Shares issued in respect thereof));

(iii) third, the Series B Registrable Shares (or, if necessary, such Series B Registrable Shares will be cut back pro rata among the holders thereof based upon the number of Series B Registrable Shares requested to be registered by each such holder (or Series B Registrable Shares issued in respect thereof));

(iv) fourth, the Non-Series B/C March 2013 Note Registrable Shares (or, if necessary, such Non-Series B/C March 2013 Note Registrable Shares will be cut back pro rata among the holders thereof based upon the number of Non-Series B/C March 2013 Note Registrable Shares requested to be registered by each such holder (or Non-Series B/C March 2013 Note Registrable Shares issued in respect thereof), provided, however, that in no event will Registrable Shares be cut back pursuant to this clause (iv) or clauses (ii) or (iii) above to the point that Registrable Shares in aggregate constitute less than thirty five percent (35%) of the total number of shares registered in any registration under this Section 3); and

(v) fifth, the Other Shares requested to be included in such registration (or, if necessary, such Other Shares pro rata among the holders thereof based upon the number of Other Shares requested to be registered by each such holder);

14. The figure “333,333” in Section 15 of the Registration Rights Agreement is hereby deleted and replaced with the figure “3,000,000.”

15. The reference to “Edwards Angell Palmer & Dodge, LLP” in Section 17(i) of the Registration Rights Agreement is hereby deleted and replaced by the words “Edwards Wildman Palmer LLP.”

16. Section 18 of the Registration Rights Agreement is hereby deleted in its entirety and the following new Section 18 is substituted in lieu thereof:

The terms and provisions of this Agreement may not be modified or amended, nor may any provision be waived, except pursuant to a writing signed by the Company and the holders of at least a majority of the Registrable Shares then outstanding which are issued or issuable upon conversion of the Preferred Stock; provided, however, that at any time when shares of Series C Preferred Stock are outstanding, no amendment or waiver of

Section 2(b)(iii) or Section 3 hereof, which would change the priority of the Series C Registrable Shares relative to the Series B Registrable Shares and/or Non-Series B/C March 2013 Note Registrable Shares with respect to cut-backs, may be made without the written consent of the holders of two-thirds of the aggregate of the then outstanding shares of the Series C Preferred Stock; provided, further, that at any time when any Warrants or Warrant Stock are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the Warrants or Warrant Stock, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding Warrants and Warrant Stock; provided, further, that at any time when any June 2011 Notes or June 2011 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the June 2011 Notes or June 2011 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding June 2011 Notes and June 2011 Note Shares; provided, further, that at any time when any December 2011 Notes or December 2011 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the December 2011 Notes or December 2011 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding December 2011 Notes and December 2011 Note Shares; provided, further, that at any time when any June 2012 Notes or June 2012 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the June 2012 Notes or June 2012 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding June 2012 Notes or June 2012 Note Shares; provided, further, that at any time when any March 2013 Notes or March 2013 Note Shares are outstanding, no amendment or waiver of any term or provision of this Agreement that is disproportionately adverse to the holders of the March 2013 Notes or March 2013 Note Shares, as compared to the holders of the Registrable Shares, may be made without the written consent of the holders of two-thirds of the then outstanding March 2013 Notes or March 2013 Note Shares.

17. Section 22 of the Registration Rights Agreement is hereby amended to insert the following sentence at the beginning:

Notwithstanding anything to the contrary contained herein, if the Company issues additional March 2013 Notes after the date hereof pursuant to the March 2013 Purchase Agreement, any purchaser of such March 2013 Notes may become a party to this Agreement by executing and delivering an additional counterpart signature page to this Agreement, and thereafter shall be deemed an “Investor” for all purposes hereunder.

18. Except to the extent amended hereby, all of the terms, provisions and conditions of the Registration Rights Agreement are hereby ratified and confirmed and shall remain in full force and effect.

19. This Amendment may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Amendment may be executed by facsimile or by electronic or PDF file.

[Signature pages to follow]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

GKFF VENTURES I, LLC (f/k/a Argonaut Ventures I, LLC)
By:	/s/ Robert Thomas
Name:	Robert Thomas
Title:	Manager and Vice President

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

RESERVOIR CAPITAL MASTER FUND, L.P.
By:	Reservoir Capital Group, L.L.C.
Its:	General Partner

By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer

RESERVOIR CAPITAL PARTNERS, L.P.
By:	RCP GP, LLC
Its:	General Partner

By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ARCAPITA VENTURES I LIMITED
By:	/s/ John Huntz
Name:	John Huntz
Title:	Executive Director

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

BASF VENTURE CAPITAL GMBH
By:	/s/ Dirk Nachtigal
Name:	Dirk Nachtigal
Title:	Managing Director

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

TENAYA CAPITAL IV, L.P.

By: Tenaya Capital IV Annex GP, LLC, its General Partner

By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact

TENAYA CAPITAL IV-C, L.P.
By:	Tenaya Capital IV GP, LP, its General Partner
By:	Tenaya Capital IV GP, LLC, its General Partner

By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact

TENAYA CAPITAL IV-P, L.P.
By:	Tenaya Capital IV GP, LP, its General Partner
By:	Tenaya Capital IV GP, LLC, its General Partner

By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

LEHMAN BROTHERS OFFSHORE PARTNERSHIP ACCOUNT 2000/2001, L.P.
By:	Lehman Brothers Offshore Partners Ltd
Its:	General Partner

By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory

LEHMAN BROTHERS PARTNERSHIP ACCOUNT 2000/2001, L.P.
By:	LBI Group Inc.
Its:	General Partner

By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory

LEHMAN BROTHERS VENTURE CAPITAL PARTNERS II, L.P.
By:	Venture Associates II GP LP
Its:	General Partner
By:	Lehman Brothers Venture Associates II LLC
Its:	General Partner

By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

ROCKPORT CAPITAL PARTNERS, L.P.
By:	RockPort Capital, L.L.C.
Its:	General Partner

By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner

ROCKPORT CAPITAL PARTNERS II, L.P.
By:	RockPort Capital II, L.L.C.
Its:	General Partner

By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner

RP CO-INVESTMENT FUND I, L.P.
By:	RP Co-Investments Fund I, GP, LLC
Its:	General Partner

By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY SELECT PORTFOLIOS: MATERIALS
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

VARIABLE INSURANCE PRODUCTS FUND III: BALANCED PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

VARIABLE INSURANCE PRODUCTS FUND IV: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

VARIABLE INSURANCE PRODUCTS FUND IV: MATERIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY ADVISOR SERIES I: FIDELITY ADVISOR DIVIDEND GROWTH FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

FIDELITY ADVISOR SERIES VII: FIDELITY ADVISOR INDUSTRIALS FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY INDUSTRIALS CENTRAL FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY MATERIALS CENTRAL FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

FIDELITY PURITAN TRUST: FIDELITY PURITAN FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

FIDELITY SECURITIES FUND: FIDELITY DIVIDEND GROWTH FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

FIDELITY SELECT PORTFOLIOS: ENVIRONMENTAL AND ALTERNATIVE ENERGY PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

FIDELITY SELECT PORTFOLIOS: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

CONTRA COSTA CAPITAL, LLC
By:	/s/ James Huff
Name:	James Huff
Title:	Vice President

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

MOUNT HOPE ASPEN, LLC
By:	/s/ Brian Scanlan
Name:	Brian Scanlan
Title:	Manager

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

IN WITNESS WHEREOF, the parties hereto have executed this Amendment No. 2 to Sixth Amended and Restated Registration Rights Agreement as of the date first written above.

NICHIAS CORPORATION
By:	/s/ Kunihiko Yano
Name:	Kunihiko Yano
Title:	President and Chief Executive Officer NICHIAS Corporation

[Signature Page to Amend. No. 2 to Sixth Amended and Restated Registration Rights Agreement]

EX-10.1.1

Exhibit 10.1.1

ASPEN AEROGELS, INC.

2001 EQUITY INCENTIVE PLAN, AS AMENDED THROUGH DECEMBER 18, 2013

SECTION 1. Purpose; Definitions. The purposes of the Aspen Aerogels, Inc. 2001 Equity Incentive Plan (the “Plan”) are to: (a) assist Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and its affiliated companies in recruiting and retaining highly qualified employees, directors and consultants; (b) provide those employees, directors and consultants with an incentive for productivity; and (c) provide those employees, directors and consultants with an opportunity to share in the growth and value of the Company.

For purposes of the Plan, the following initially capitalized words and phrases will be defined as set forth below, unless the context clearly requires a different meaning:

a. “Affiliate” means, with respect to a person or entity, a person that directly or indirectly controls, or is controlled by, or is under common control with such person or entity.

b. “Award” means a grant of Options or Restricted Shares pursuant to the provisions of this Plan.

c. “Award Agreement” means, with respect to any particular Award, the written document that sets forth the terms of that particular Award.

d. “Board” means the Board of Directors of the Company, as constituted from time to time; provided, however, that if the Board appoints a Committee to perform some or all of the Board’s administrative functions hereunder pursuant to Section 2, references in this Plan to the “Board” will be deemed to also refer to that Committee in connection with administrative matters to be performed by that Committee.

e. “Cause” exists when the Participant (as determined by the Board, in its sole discretion):

(i) engages in any type of disloyalty to the Company or any of its Affiliates, including without limitation, fraud, embezzlement, theft, or dishonesty in the course of his employment or engagement, or otherwise breaches any fiduciary duty owed to the Company or any of its Affiliates;

(ii) is convicted of a felony or a misdemeanor involving moral turpitude;

(iii) enters a plea of guilty or nolo contendere to a felony or a misdemeanor involving moral turpitude;

(iv) discloses any confidential, proprietary, business or technical information or trade secret of the Company or of any of its Affiliates; or

(v) breaches any agreement with or duty to the Company.

“Cause” is not limited to events which have occurred prior to a Participant’s termination of service, nor is it necessary that the Board’s finding of “Cause” occur prior to termination. If the Board determines, subsequent to a Participant’s termination of service but prior to the exercise of an Option, that either prior or subsequent to the Participant’s termination the Participant engaged in conduct which would constitute “Cause,” then the right to exercise any Option is forfeited.

f. “Code” means the Internal Revenue Code of 1986, as amended from time to time, and any successor thereto.

g. “Committee” will mean a committee appointed by the Board in accordance with Section 2 of this Plan.

h. “Common Stock” means the Company’s Common Stock, $0.00001 par value per share.

i. “Director” means a member of the Board.

j. “Disability” will mean a disability which renders an individual unable to perform the full extent of his duties and responsibilities to the Company or its subsidiaries by reason of his illness or incapacity which would entitle that employee or Director to receive Social Security Disability Income under the Social Security Act, as amended, and the regulations promulgated thereunder. “Disabled” will mean having a Disability. The determination of whether a Participant is Disabled will be made by the Board, whose determination will be conclusive; provided, however, that if a Participant is bound by the terms of an employment or consulting agreement between the Participant and the Company, whether the Participant is “Disabled” for purposes of the Plan will be determined in accordance with the procedures set forth in said employment agreement, if such procedures are therein provided.

k. “Exchange Act” means the Securities Exchange Act of 1934, as amended.

l. “Fair Market Value” means, as of any date: (i) if the Shares are not listed or admitted to unlisted trading privileges on a nationally recognized stock exchange, the value of such Shares on that date, as determined by the Board in good faith; or (ii) if the Shares are listed or admitted to unlisted trading privileges on a nationally recognized stock exchange, the closing price of the Shares as reported on the principal nationally recognized stock exchange on which the Shares are traded on such date, or if no Share prices are reported on such date, the closing price of the Shares on the next preceding date on which there were reported Share prices.

m. “Incentive Stock Option” means any Option intended to be and designated as an “Incentive Stock Option” within the meaning of Section 422 of the Code.

n. “Non-Employee Director” will have the meaning set forth in Rule 16b-3(b)(3)(i) promulgated by the Securities and Exchange Commission under the Exchange Act, or any successor definition adopted by the Securities and Exchange Commission; provided, however, that the Board or the Committee may, to the extent that it deems necessary to comply with Section 162(m) of the Code or regulations thereunder, require that each “Non-Employee Director” also be an “outside director” as that term is defined in regulations under Section 162(m).

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o. “Non-Qualified Stock Option” means any Option that is not an Incentive Stock Option.

p. “Option” means any option to purchase Shares (including Restricted Shares, if the Committee so determines) granted pursuant to Section 5 hereof.

q. “Participant” means an employee, consultant or Director of the Company or any of its Affiliates to whom an Award is granted.

r. “Person” means an individual, partnership, corporation, limited liability company, trust, joint venture, unincorporated association, or other entity or association.

s. “Restricted Shares” means Shares that are subject to restrictions pursuant to Section 9 hereof.

t. “Share” means a share of Common Stock, subject to substitution or adjustment as provided in Section 3(c) hereof.

u. “Subsidiary” means, in respect of the Company, a subsidiary company, whether now or hereafter existing, as defined in Sections 424(f) and (g) of the Code.

v. “Survivors” means a deceased Participant’s legal representatives and/or any person or persons who acquired the Participant’s rights to an Option by will or by the laws of descent and distribution.

SECTION 2. Administration. The Plan will be administered by the Board; provided, however, that the Board may at any time appoint a Committee to perform some or all of the Board’s administrative functions hereunder; and provided further, that the authority of any Committee appointed pursuant to this Section 2 will be subject to such terms and conditions as the Board may prescribe and will be coextensive with, and not in lieu of, the authority of the Board hereunder.

Any Committee established under this Section 2 will be composed of not fewer than two members, each of whom will serve for such period of time as the Board determines; provided, however, that if the Company has a class of securities required to be registered under Section 12 of the Securities Exchange Act of 1934, all members of any Committee established pursuant to this Section 2 will be Non-Employee Directors. From time to time the Board may increase the size of the Committee and appoint additional members thereto, remove members (with or without cause) and appoint new members in substitution therefor, fill vacancies however caused, or remove all members of the Committee and thereafter directly administer the Plan.

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Members of the Board who are eligible for Awards or have received Awards may vote on any matters affecting the administration of the Plan or the grant of Awards, except that no such member will act upon the grant of an Award to himself or herself, but any such member may be counted in determining the existence of a quorum at any meeting of the Board during which action is taken with respect to the grant of Awards to himself or herself.

The Board will have full authority to grant Awards under this Plan. In particular, the Board will have the authority:

a. to select the persons to whom Awards may from time to time be granted hereunder (consistent with the eligibility conditions set forth in Section 4);

b. to determine the type of Award to be granted to any person hereunder;

c. to determine the number of Shares, if any, to be covered by each such Award;

d. to establish the terms and conditions of each Award Agreement;

e. to determine whether and under what circumstances an Option may be exercised without a payment of cash under Section 5(d); and

f. to determine whether, to what extent and under what circumstances Shares and other amounts payable with respect to an Award may be deferred either automatically or at the election of the Participant.

The Board will have the authority to adopt, alter and repeal such administrative rules, guidelines and practices governing the Plan as it, from time to time, deems advisable; to interpret the terms and provisions of the Plan and any Award issued under the Plan (and any Award Agreement); to amend the terms of any Award Agreement, provided that the Participant consents to such amendment; and to otherwise supervise the administration of the Plan. The Board may correct any defect, supply any omission or reconcile any inconsistency in the Plan or in any Award in the manner and to the extent it deems necessary to carry out the intent of the Plan.

All decisions made by the Board pursuant to the provisions of the Plan will be final and binding on all persons, including the Company and Participants. No member of the Board will be liable for any good faith determination, act or omission in connection with the Plan or any Award.

SECTION 3. Shares Subject to the Plan.

a. Shares Subject to the Plan. The Shares to be subject to Options or Restricted Shares under the Plan will be authorized and unissued Shares of the Company, whether or not previously issued and subsequently acquired by the Company. The maximum number of Shares that may be subject to Options or Restricted Shares under the Plan is 82,828,526 subject to adjustment by the Board, and the Company will reserve for the purposes of the Plan, out of its authorized but unissued Shares, such number of Shares. Notwithstanding anything to the contrary in this Section 3(a) or this Plan, upon exercise of any Option the Shares issuable therefore shall be issued from the treasury stock of the Company.

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b. Effect of the Expiration or Termination of Awards. If and to the extent that an Option expires, terminates or is canceled or forfeited for any reason without having been exercised in full, the Shares associated with that Option will again become available for grant under the Plan. Similarly, if and to the extent that any Restricted Share is canceled, repurchased or forfeited for any reason, that Share will again become available for grant under the Plan.

c. Other Adjustment. Upon the occurrence of any of the following events, a Participant’s rights with respect to any Option granted to him or her hereunder which has not previously been exercised in full shall be adjusted as hereinafter provided, unless otherwise specifically provided in the pertinent Award Agreement:

(i) Stock Dividends and Stock Splits. If the Shares shall be subdivided or combined into a greater or smaller number of shares or if the Company shall issue any shares of Common Stock as a stock dividend on its outstanding Common Stock, the number of Shares deliverable upon the exercise of such Option shall be appropriately increased or decreased proportionately, and appropriate adjustments shall be made in the purchase price per share to reflect such subdivision, combination or stock dividend.

(ii) Consolidations or Mergers. If the Company is to be consolidated with or acquired by another entity in a merger, sale of all or substantially all of the Company’s assets or otherwise (an “Acquisition”), the Board or the board of directors of any entity assuming the obligations of the Company hereunder (the “Successor Board”), shall, as to outstanding Options, either (i) make appropriate provision for the continuation of such Options by substituting on an equitable basis for the Shares then subject to such Options either the consideration payable with respect to the outstanding shares of Common Stock in connection with the Acquisition or securities of any successor or acquiring entity; or (ii) upon written notice to the Participants, provide that all Options must be exercised (either to the extent then exercisable or, at the discretion of the Board, all Options being made fully exercisable for purposes of this Subparagraph), within a specified number of days of the date of such notice, at the end of which period the Options shall terminate; or (iii) terminate all Options in exchange for a cash payment equal to the excess of the Fair Market Value of the shares subject to such Options (either to the extent then exercisable or, at the discretion of the Board, all Options being made fully exercisable for purposes of this Subparagraph) over the exercise price thereof.

(iii) Recapitalization or Reorganization. In the event of a recapitalization or reorganization of the Company (other than a transaction described in Subparagraph (ii) above) pursuant to which securities of the Company or of another corporation are issued with respect to the outstanding shares of Common Stock, a Participant upon exercising an Option shall be entitled to receive for the purchase price paid upon such exercise the securities which would have been received if such Option had been exercised prior to such recapitalization or reorganization.

(iv) Modification of Incentive Stock Options. Notwithstanding the foregoing, any adjustments made pursuant to Subparagraph (i), (ii) or (iii) with respect to Incentive Stock Options shall be made only after the Board, after consulting with counsel for the Company, determines whether such adjustments would constitute a “modification” of such Options (as that term is defined in Section 424(h) of the Code) or would cause any adverse tax

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consequences for the holders of such Incentive Stock Options. If the Board determines that such adjustments made with respect to Incentive Stock Options would constitute a modification of such Options, it may refrain from making such adjustments, unless the holder of an Incentive Stock Options specifically requests in writing that such adjustment be made and such writing indicates that the holder has full knowledge of the consequences of such “modification” on his or her income tax treatment with respect to the Incentive Stock Options.

SECTION 4. Eligibility. Employees, directors, consultants, and other individuals who provide services to the Company or its Affiliates are eligible to be granted Awards under the Plan. Persons who are not employees of the Company or a Subsidiary are eligible to be granted Awards, but are not eligible to be granted Incentive Stock Options.

SECTION 5. Options. Options granted under the Plan may be of two types: (i) Incentive Stock Options or (ii) Non-Qualified Stock Options. Options may be granted alone or in addition to other Awards. Any Option granted under the Plan will be in such form as the Board may from time to time approve.

The Award Agreement evidencing any Option will incorporate the following terms and conditions and will contain such additional terms and conditions, not inconsistent with the terms of the Plan, as the Board deems appropriate in its sole and absolute discretion:

a. Option Price. The exercise price per Share purchasable under a Non-Qualified Stock Option will be determined by the Board. The exercise price per Share purchasable under an Incentive Stock Option will be not less than 100% of the Fair Market Value of the Share on the date of the grant. However, any Incentive Stock Option granted to any Participant who, at the time the Option is granted, owns more than 10% of the voting power of all classes of shares of the Company or of a Subsidiary will have an exercise price per Share of not less than 110% of Fair Market Value per Share on the date of the grant.

b. Option Term. The term of each Option will be fixed by the Board, but no Option will be exercisable more than ten (10) years after the date the Option is granted. However, any Incentive Stock Option granted to any Participant who, at the time such Option is granted, owns more than 10% of the voting power of all classes of shares of the Company or of a Subsidiary may not have a term of more than five (5) years. No Option may be exercised by any person after expiration of the term of the Option.

c. Exercisability. Options will vest and be exercisable at such time or times and subject to such terms and conditions as determined by the Board at the time of grant. If the Board provides, in its discretion, that any Option is exercisable only in installments, the Board may waive such installment exercise provisions at any time at or after grant, in whole or in part, based on such factors as the Board determines, in its sole and absolute discretion.

d. Method of Exercise. Subject to the exercise provisions under Section 5(c) and the termination provisions set forth in Section 6, Options may be exercised in whole or in part at any time and from time to time during the term of the Option, by giving written notice of exercise to the Company specifying the number of Shares to be purchased. Such notice will be accompanied by payment in full of the purchase price, either by certified or bank check, or such

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other means as the Board may accept. As determined by the Board, in its sole discretion, at or after grant, payment in full or in part of the exercise price of an Option may be made in the form of previously acquired Shares based on the Fair Market Value of the Shares on the date the Option is exercised; provided, however, that unless the Company’s accountants advise it that no adverse accounting treatment will result from the payment of the exercise price in the form of previously acquired Shares, previously acquired Shares may not be used to pay such exercise price with respect to any Shares issued pursuant to this Agreement until six months have elapsed from the issuance of such previously acquired Shares; and provided, further, that, in the case of an Incentive Stock Option, the right to make a payment in the form of previously acquired Shares may be authorized only at the time the Option is granted.

No Shares will be issued upon exercise of an Option until full payment therefor has been made. A Participant will not have the right to distributions or dividends or any other rights of a shareholder with respect to Shares subject to the Option until the Participant has given written notice of exercise, has paid in full for such Shares, and, if requested, has given the representation described in Section 10(a) hereof.

e. Incentive Stock Option Limitations. In the case of an Incentive Stock Option, the aggregate Fair Market Value (determined as of the time of grant) of the Shares with respect to which Incentive Stock Options are exercisable for the first time by the Participant during any calendar year under the Plan and/or any other plan of the Company, its parent or any Subsidiary of the Company will not exceed $100,000. For purposes of applying the foregoing limitation, Incentive Stock Options will be taken into account in the order granted. Any Option not meeting such limitation will be treated for all purposes as a Non-Qualified Stock Option.

f. Termination of Employment. Unless otherwise specified in the Award Agreement, Options will be subject to the terms of Section 6 with respect to exercise upon termination of employment.

SECTION 6. Termination of Service. Unless otherwise specified with respect to a particular Award, Options granted hereunder will remain exercisable after termination of employment only to the extent specified in this Section 6.

a. Termination by Reason of Death. In the event of the death of the Participant while an employee of the Company or of an Affiliate, the Option shall be exercisable by the Participant’s Survivors within one (1) year after the date of death of the Participant or, if earlier, within the originally prescribed term of the Option.

b. Termination by Reason of Disability. In the event of the Disability of the Participant, as determined in accordance with the Plan, the Option shall be exercisable within one (1) year after the Participant’s termination of employment or, if earlier, within the term originally prescribed by the Option.

c. Cause. In the event a Participant’s service to the Company or one of its Affiliates is terminated by the Company or such an Affiliate for “Cause”, the Participant’s right to exercise any unexercised portion of Options shall cease as of such termination, and such

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Options shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Participant’s termination of service to the Company or one of its Affiliates for “Cause”, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Participant’s termination, the Participant engaged in conduct which would constitute “Cause,” then the Participant shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

d. Other Termination. If a Participant’s service with the Company or any Affiliate terminates for any reason other than death, Disability or Cause, any Option held by such Participant may thereafter be exercised by the Participant, to the extent it was exercisable at the time of such termination, or on such accelerated basis as the Board may determine at or after grant, for a period expiring (i) at such time as may be specified by the Board at or after the time of grant, or (ii) if not specified by the Board, then 90 days from the date of termination of service, or (iii) if sooner than the applicable period specified under (i) or (ii) above, then upon the expiration of the stated term of such Option.

SECTION 7. Restricted Shares.

a. Issuance. Restricted Shares may be issued either alone or in conjunction with other Awards. The Board will determine the time or times within which Restricted Shares may be subject to forfeiture, and all other conditions of such Awards.

b. Awards and Certificates. The Award Agreement evidencing the grant of any Restricted Shares will contain such terms and conditions, not inconsistent with the terms of the Plan, as the Board deems appropriate in its sole and absolute discretion. The prospective recipient of an Award of Restricted Shares will not have any rights with respect to such Award, unless and until such recipient has executed an Award Agreement and has delivered a fully executed copy thereof to the Company, and has otherwise complied with the applicable terms and conditions of such Award. The purchase price for Restricted Shares may, but need not, be zero.

A share certificate will be issued in connection with each Award of Restricted Shares. Such certificate will be registered on the Company’s books in the name of the Participant receiving the Award, and will bear the following legend as well as any other legend required by this Plan, the Award Agreement, the Company’s shareholders’ agreement, or by applicable law:

THE TRANSFERABILITY OF THIS CERTIFICATE AND THE SHARES REPRESENTED HEREBY ARE SUBJECT TO THE TERMS AND CONDITIONS (INCLUDING FORFEITURE) OF THE ASPEN AEROGELS, INC. 2001 EQUITY INCENTIVE PLAN AND AN AGREEMENT ENTERED INTO BETWEEN THE REGISTERED OWNER AND ASPEN AEROGELS, INC. COPIES OF SUCH PLAN AND AGREEMENT ARE ON FILE IN THE PRINCIPAL OFFICES OF ASPEN AEROGELS, INC. AND WILL BE MADE AVAILABLE TO ANY SHAREHOLDER WITHOUT CHARGE UPON REQUEST TO THE SECRETARY OF THE COMPANY.

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Share certificates evidencing Restricted Shares be held in custody by the Company or in escrow by an Escrow Agent until the restrictions thereon have lapsed, and that, as a condition of any Restricted Share Award, the Participant deliver to the Company a share power, endorsed in blank, relating to the Shares covered by such Award.

c. Restrictions and Conditions. The Restricted Shares awarded pursuant to this Section 7 will be subject to the following restrictions and conditions:

(i) During a period commencing with the date of grant of an Award of Restricted Shares and ending at such time or times as specified by the Board (the “Restriction Period”), the Participant will not be permitted to sell, transfer, pledge, assign or otherwise encumber Restricted Shares awarded under the Plan. The Board may condition the lapse of restrictions on Restricted Shares upon the continued employment or service of the recipient, the attainment of specified individual or corporate performance goals, or such other factors as the Board may determine, in its sole and absolute discretion.

(ii) Prior to the expiration of the Restriction Period, the Participant will not be entitled to receive any cash distributions or dividends paid with respect to Restricted Shares and will not be entitled to vote such Restricted Shares. A Participant will be entitled to receive any distributions or dividends paid in the form of securities with respect to Restricted Shares, but such securities will be subject to the same terms and conditions as the Restricted Shares with respect to which they were paid, including, without limitation, the same Restriction Period.

(iii) Subject to the applicable provisions of the Award Agreement, if a Participant’s service with the Company terminates prior to the expiration of the Restriction Period for reasons other than death or Disability, all of that Participant’s Restricted Shares which then remain subject to forfeiture will be forfeited.

(iv) Upon the death or Disability of a Participant during the Restriction Period:

(A) restrictions based on continued employment will lapse with respect to a percentage of the Restricted Shares granted to the Participant that is equal to the percentage of the Restriction Period that has elapsed as of the date of death or the date on which such Disability commenced (as determined by the Board in its sole discretion), and

(B) restrictions based on individual or corporate performance will lapse to the extent determined by the Board in its sole discretion.

(v) In the event of hardship or other special circumstances of a Participant whose service with the Company is involuntarily terminated (other than for Cause), the Board may, in its sole discretion, waive in whole or in part any or all remaining restrictions with respect to such Participant’s Restricted Shares, based on such factors as the Board may deem appropriate.

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(vi) If and when the Restriction Period expires without a prior forfeiture of the Restricted Shares subject to such Restriction Period (or if and when the restrictions applicable to Restricted Shares lapse pursuant to Sections 7(c)(iv) or 7(c)(v)), the certificates for such Shares will be replaced with new certificates, without the restrictive legend described in Section 7(b), and such new certificates will be promptly delivered to the Participant, the Participant’s representative (if the Participant has suffered a Disability), or the Participant’s Survivors (if the Participant has died).

SECTION 8. Amendments and Termination. The Board may amend, alter or discontinue the Plan at any time, but no amendment, alteration or discontinuation will be made which would impair the rights of a Participant with respect to an Award that is outstanding under the Plan, without the Participant’s consent, or which, without the approval of such amendment within one year (365 days) of its adoption by the Board, by a majority of the votes cast at a duly held shareholder meeting at which a quorum representing a majority of the Company’s outstanding voting shares is present (either in person or by proxy), would: (i) increase the total number of Shares reserved for the purposes of the Plan (except as otherwise provided in Section 3(c)), or (ii) change the persons or class of persons eligible to receive Awards.

SECTION 9. Unfunded Status of Plan. The Plan is intended to be “unfunded.” With respect to any payments not yet made to a Participant by the Company, nothing contained herein will give any such Participant any rights that are greater than those of a general creditor of the Company. In its sole discretion, the Board may authorize the creation of grantor trusts or other arrangements to meet the obligations created under the Plan to deliver Shares or payments in lieu of Shares or with respect to other Awards hereunder.

SECTION 10. General Provisions.

a. The Board may require each Participant to represent to and agree with the Company in writing that the Participant is acquiring securities of the Company for investment purposes and without a view to distribution thereof and as to such other matters as the Board believes are appropriate. The certificate evidencing any Award and any securities issued pursuant thereto may include any legend which the Board deems appropriate to reflect any restrictions on transfer and compliance with securities laws.

All certificates for Shares or other securities delivered under the Plan will be subject to such share-transfer orders and other restrictions as the Board may deem advisable under the rules, regulations, and other requirements of the Securities Act of 1933, as amended, the Exchange Act, any stock exchange upon which the Shares are then listed, and any other applicable Federal or state securities laws, and the Board may cause a legend or legends to be put on any such certificates to make appropriate reference to such restrictions.

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b. Nothing contained in the Plan will prevent the Board from adopting other or additional compensation arrangements, subject to shareholder approval if such approval is required; and such arrangements may be either generally applicable or applicable only in specific cases.

c. The adoption of the Plan will not confer upon any employee of the Company or a Subsidiary any right to continued employment with the Company or such Subsidiary, nor will it interfere in any way with the right of the Company or such Subsidiary to terminate the employment of any of its employees at any time.

d. No later than the date as of which an amount first becomes includible in the gross income of the Participant for Federal income tax purposes with respect to any Award under the Plan, the Participant will pay to the Company, or make arrangements satisfactory to the Board regarding the payment of, any Federal, state or local taxes of any kind required by law to be withheld with respect to such amount. Unless otherwise determined by the Board, the minimum required withholding obligations may be settled with Shares, including Shares that are part of the Award that gives rise to the withholding requirement. The obligations of the Company under the Plan will be conditioned on such payment or arrangements and the Company will, to the extent permitted by law, have the right to deduct any such taxes from any payment of any kind otherwise due to the Participant.

e. The Board will establish such procedures as it deems appropriate for a Participant to designate a beneficiary to whom any amounts payable in the event of the Participant’s death are to be paid.

f. Except as may otherwise be specifically determined by the Board with respect to a particular Award, no Award will be transferable by the Participant otherwise than by will or by the laws of descent and distribution, and all Awards will be exercisable, during the Participant’s lifetime, only by the Participant or, in the event of his Disability, by his personal representative.

SECTION 11. Effective Date of Plan. This Plan will become effective on the date that it is approved by a majority of the votes cast at a duly held shareholder meeting at which a quorum representing a majority of Company’s outstanding voting shares is present, either in person or by proxy.

SECTION 12. Term of Plan. This Plan will continue in effect until terminated in accordance with Section 8; provided, however, that no Incentive Stock Option will be granted hereunder on or after the tenth (10th) anniversary of the date of shareholder approval of the Plan; but provided further, that Incentive Stock Options granted prior to such tenth anniversary may extend beyond that date.

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SECTION 13. Invalid Provisions. In the event that any provision of this Plan is found to be invalid or otherwise unenforceable under any applicable law, such invalidity or unenforceability will not be construed as rendering any other provisions contained herein as invalid or unenforceable, and all such other provisions will be given full force and effect to the same extent as though the invalid or unenforceable provision was not contained herein.

SECTION 14. Governing Law. This Plan and all Awards granted hereunder will be governed by and construed in accordance with the laws and judicial decisions of the State of Delaware, without regard to the application of the principles of conflicts of laws.

SECTION 15. Board Action. Notwithstanding anything to the contrary set forth in this Plan, any and all actions of the Board or Committee, as the case may be, taken under or in connection with this Plan and any agreements, instruments, documents, certificates or other writings entered into, executed, granted, issued and/or delivered pursuant to the terms hereof, will be subject to and limited by any and all votes, consents, approvals, waivers or other actions of all or certain stockholders of the Company or other persons required by:

a. the Company’s governing documents (as the same may be amended and/or restated from time to time); and

b. any other agreement, instrument, document or writing now or hereafter existing, between or among the Company and its stockholders or other persons (as the same may be amended from time to time).

SECTION 16. Notices. Any notice to be given to the Company pursuant to the provisions of the Plan shall be addressed to the Company in care of its Secretary (or such other person as the Company may designate from time to time) at its principal executive office, and any notice to be given to a Participant shall be delivered personally or addressed to him or her at the address given beneath his or her signature on his or her Award Agreement, or at such other address as such Participant may hereafter designate in writing to the Company. Any such notice shall be deemed duly given on the date and at the time delivered via personal, courier or recognized overnight delivery service or, if sent via telecopier, on the date and at the time telecopied with confirmation of delivery or, if mailed, on the date five (5) days after the date of the mailing (which shall be by regular, registered or certified mail). Delivery of a notice by telecopy (with confirmation) shall be permitted and shall be considered delivery of a notice notwithstanding that it is not an original that is received.

SECTION 17. Dissolution or Liquidation of the Company. Upon the dissolution or liquidation of the Company, all Options granted under this Plan which as of such date shall not have been exercised will terminate and become null and void; provided, however, that if the rights of a Participant or a Participant’s Survivors have not otherwise terminated and expired, the Participant or the Participant’s Survivors will have the right immediately prior to such dissolution or liquidation to exercise any Option to the extent that the Option is exercisable as of the date immediately prior to such dissolution or liquidation.

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SECTION 18. Issuances of Securities. Except as expressly provided herein, no issuance by the Company of shares of stock of any class, or securities convertible into shares of stock of any class, shall affect, and no adjustment by reason thereof shall be made with respect to, the number or price of shares subject to Options. Except as expressly provided herein, no adjustments shall be made for dividends paid in cash or in property (including without limitation, securities) of the Company.

SECTION 19. Fractional Shares. No fractional shares shall be issued under the Plan and the person exercising such right shall receive from the Company cash in lieu of such fractional shares equal to the Fair Market Value thereof.

SECTION 20. Conversion of Incentive Stock Options into Non-Qualified Stock Options; Termination of Incentive Stock Options. The Board, at the written request of any Participant, may in its discretion take such actions as may be necessary to convert such Participant’s Incentive Stock Options (or any portions thereof) that have not been exercised on the date of conversion into Non-Qualified Stock Options at any time prior to the expiration of such Incentive Stock Options, regardless of whether the Participant is an employee of the Company or an Affiliate at the time of such conversion. Such actions may include, but not be limited to, extending the exercise period or reducing the exercise price of the appropriate installments of such Options. At the time of such conversion, the Board (with the consent of the Participant) may impose such conditions on the exercise of the resulting Non-Qualified Stock Options as the Board in its discretion may determine, provided that such conditions shall not be inconsistent with this Plan. Nothing in the Plan shall be deemed to give any Participant the right to have such Participant’s Incentive Stock Options converted into Non-Qualified Stock Options, and no such conversion shall occur until and unless the Board takes appropriate action. The Board, with the consent of the Participant, may also terminate any portion of any Incentive Stock Option that has not been exercised at the time of such conversion.

SECTION 21. Notice to Company of Disqualifying Disposition. Each Participant who receives an Incentive Stock Option must agree to notify the Company in writing immediately after the Key Employee makes a “Disqualifying Disposition” of any Shares acquired pursuant to the exercise of an Incentive Stock Option. A “Disqualifying Disposition” is any disposition (including any sale) of such shares before the later of (a) two years after the date the Participant was granted the Incentive Stock Option, or (b) one year after the date Participant acquired Shares by exercising the Incentive Stock Option. If the Participant has died before such stock is sold, these holding period requirements do not apply and no Disqualifying Disposition can occur thereafter.

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EX-10.1.2

Exhibit 10.1.2

ISO-[    ] [            ] Shares

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through December 18, 2013)

Incentive Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Incentive Stock Option Agreement (the “Agreement”) attached to this Incentive Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:
Purchase Price:	$[            ] per share
Date of Grant:	, 201[  ]
Exercisability Schedule:	The Options shall vest and become exercisable in accordance with the following vesting schedule:
	25% of the Shares will vest and become exercisable on the first anniversary of the Date of Grant, and the remaining 75% of the Shares shall vest and become exercisable in equal monthly installments over the 36 months following the first anniversary of the Date of Grant; provided that in the event of a Change in Control 12 months of this vesting schedule shall be accelerated.
Expiration Date:	10 year anniversary of Date of Grant

This Option is intended to be treated as an Incentive Stock Option under section 422 of the Internal Revenue Code of 1986, as amended (the “Code”). By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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INCENTIVE STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Incentive Stock Option Certificate to which this Incentive Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”) (the “Plan”); and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be an Incentive Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION; TERMINATION OF PRIOR OPTIONS. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan. If the Optionee ceases to be an employee of the Company or of an Affiliate (for any reason other than the death or Disability of the Optionee or termination by the Optionee’s employer for Cause), the Option may be exercised to the extent then vested at termination, if it has not previously terminated, within ninety (90) days after the date the Optionee ceases to be an employee of the Company or an Affiliate, at such time as may be specified by the Board at or after the time of grant or within the originally prescribed term of the Option, whichever is earlier, but may not be exercised thereafter

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In the event the Optionee’s employment is terminated by the Optionee’s employer for Cause, the Optionee’s right to exercise any unexercised portion of this Option shall cease as of such termination, and this Option shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Optionee’s termination as an employee, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Optionee’s termination, the Optionee engaged in conduct which would constitute Cause, then the Optionee shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

In the event of the Disability of the Optionee, as determined in accordance with the Plan, or if the Optionee is determined to be disabled under the Company’s long-term disability plan, the Option shall be exercisable to the extent then vested at Disability within one (1) year after the termination of Optionee’s employment or, if earlier, within the term originally prescribed by the Option.

In the event of the death of the Optionee while an employee of the Company or of an Affiliate, the Option shall be exercisable to the extent vested at death by the Optionee’s Survivors within one (1) year after the date of death of the Optionee or, if earlier, within the originally prescribed term of the Option.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment

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duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such

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person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. NO OBLIGATION TO EMPLOY. The Company is not by the Plan or this Option obligated to continue the Optionee as an employee of the Company.

13. OPTION IS INTENDED TO BE AN INCENTIVE STOCK OPTION. The parties each intend that the Option be an Incentive Stock Option so that the Optionee (or in the event of Optionee’s death, Optionee’s legal representatives and/or any person who acquired Optionee’s rights to an Option in accordance with Section 7 hereof) may qualify for the favorable tax treatment provided to holders of Options that meet the standards of Section 422 of the Code.

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Nonetheless, if all or any part of the Option is determined not to be an Incentive Stock Option, the Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option and the requirements necessary to obtain favorable tax treatment under Section 422 of the Code, including, but not limited to, holding period requirements.

14. NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION. The Optionee agrees to notify the Company in writing immediately after the Optionee makes a Disqualifying Disposition of any of the Shares acquired pursuant to the exercise of the Option. A Disqualifying Disposition is defined in Section 424(c) of the Code and includes any disposition (including any sale) of such Shares before the later of (a) two years after the date the Optionee was granted the Option or (b) one year after the date the Optionee acquired Shares by exercising the Option, except as otherwise provided in Section 424(c) of the Code. If the Optionee has died before the Shares are sold, these holding period requirements do not apply and no Disqualifying Disposition can occur thereafter.

15. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 15.

16. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

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or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

17. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

18. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

19. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

20. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 21 below.

21. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF INCENTIVE STOCK OPTION

[Form For Unregistered Shares]

To: Aspen Aerogels, Inc.

30 Forbes Road, Bldg B

Northborough, MA 01532

Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Incentive Stock Option to purchase             shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Incentive Stock Option Agreement between the undersigned and the Company dated as of                 , 201[  ].

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                     

Please issue the stock certificate for the Shares in the name of                     , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                    .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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EX-10.1.3

Exhibit 10.1.3

2013 (Re-Pricing) ISO-[    ] [            ] Shares                    

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through August 7, 2013)

Incentive Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through August 7, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Incentive Stock Option Agreement (the “Agreement”) attached to this Incentive Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:
Purchase Price:	$0.09 per share
Date of Grant:	, 2013
Exercisability Schedule:	The Options shall vest and become exercisable in accordance with the following vesting schedule:
	40% of the Shares will vest and become exercisable on the Date of Grant, and the remaining 60% of the Shares shall vest and become exercisable in equal monthly installments over the 36 months following the Date of Grant; provided that in the event of a Change in Control 12 months of this vesting schedule shall be accelerated.
Expiration Date:	10 year anniversary of Date of Grant

This Option is intended to be treated as an Incentive Stock Option under section 422 of the Internal Revenue Code of 1986, as amended (the “Code”). By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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INCENTIVE STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Incentive Stock Option Certificate to which this Incentive Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through August 7, 2013 (the “Plan”) (the “Plan”); and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be an Incentive Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION; TERMINATION OF PRIOR OPTIONS. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan. Any and all options to purchase any capital securities of the Company that were granted to the Optionee prior to the date hereof, and the agreements entered into in connection therewith, if any, are hereby terminated and cancelled by the Company and the Optionee.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan. If the Optionee ceases to be an employee of the Company or of an Affiliate (for any reason other than the death or Disability of the Optionee or termination by the Optionee’s employer for Cause), the Option may be exercised to the extent then vested at termination, if it has not previously terminated, within ninety (90) days after the date the Optionee ceases to be an employee of the Company or an Affiliate, at such time as may be specified by the Board at or after the time of grant or within the originally prescribed term of the Option, whichever is earlier, but may not be exercised thereafter

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In the event the Optionee’s employment is terminated by the Optionee’s employer for Cause, the Optionee’s right to exercise any unexercised portion of this Option shall cease as of such termination, and this Option shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Optionee’s termination as an employee, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Optionee’s termination, the Optionee engaged in conduct which would constitute Cause, then the Optionee shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

In the event of the Disability of the Optionee, as determined in accordance with the Plan, or if the Optionee is determined to be disabled under the Company’s long-term disability plan, the Option shall be exercisable to the extent then vested at Disability within one (1) year after the termination of Optionee’s employment or, if earlier, within the term originally prescribed by the Option.

In the event of the death of the Optionee while an employee of the Company or of an Affiliate, the Option shall be exercisable to the extent vested at death by the Optionee’s Survivors within one (1) year after the date of death of the Optionee or, if earlier, within the originally prescribed term of the Option.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

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(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due

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from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. NO OBLIGATION TO EMPLOY. The Company is not by the Plan or this Option obligated to continue the Optionee as an employee of the Company.

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13. OPTION IS INTENDED TO BE AN INCENTIVE STOCK OPTION. The parties each intend that the Option be an Incentive Stock Option so that the Optionee (or in the event of Optionee’s death, Optionee’s legal representatives and/or any person who acquired Optionee’s rights to an Option in accordance with Section 7 hereof) may qualify for the favorable tax treatment provided to holders of Options that meet the standards of Section 422 of the Code. Nonetheless, if all or any part of the Option is determined not to be an Incentive Stock Option, the Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option and the requirements necessary to obtain favorable tax treatment under Section 422 of the Code, including, but not limited to, holding period requirements.

14. NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION. The Optionee agrees to notify the Company in writing immediately after the Optionee makes a Disqualifying Disposition of any of the Shares acquired pursuant to the exercise of the Option. A Disqualifying Disposition is defined in Section 424(c) of the Code and includes any disposition (including any sale) of such Shares before the later of (a) two years after the date the Optionee was granted the Option or (b) one year after the date the Optionee acquired Shares by exercising the Option, except as otherwise provided in Section 424(c) of the Code. If the Optionee has died before the Shares are sold, these holding period requirements do not apply and no Disqualifying Disposition can occur thereafter.

15. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 14.

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16. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

17. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

18. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

19. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

20. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 21 below.

21. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to

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any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF INCENTIVE STOCK OPTION

[Form For Unregistered Shares]

To: Aspen Aerogels, Inc.

30 Forbes Road, Bldg B

Northborough, MA 01532

Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Incentive Stock Option to purchase              shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Incentive Stock Option Agreement between the undersigned and the Company dated as of                     , 2013.

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                     

Please issue the stock certificate for the Shares in the name of                             , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                            .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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EX-10.1.4

Exhibit 10.1.4

(IPO) ISO-[    ] [            ] Shares                    

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through December 18, 2013)

Incentive Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Incentive Stock Option Agreement (the “Agreement”) attached to this Incentive Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:	(subject to adjustment as set forth below)
Adjustment to Number of Shares:	Automatically upon the consummation of an IPO (as defined below), the number of Shares subject to this Option shall be reduced to a number of Shares, that when combined with the number of shares of Common Stock issuable under Optionee’s total option holdings (including this Option), shall be equal to [        ] percent (the “Target Percentage”) of the Common Stock Deemed Outstanding (as defined below) as of immediately prior to the consummation of the IPO and any balance of the Shares subject to this Option resulting from such reduction shall thereupon be forfeited by Optionee. If the number of Shares subject to this Option is insufficient to achieve the Target Percentage, the Company is under no obligation to grant additional options to Optionee. Common Stock Deemed Outstanding is defined in Section 3 of the Agreement.
Purchase Price:	$[            ] per share

Date of Grant:	, 201[  ]
Exercisability Schedule:	The Options shall vest and become exercisable only in the event that there shall occur the consummation of a public offering of the equity of the Company pursuant to a registration statement filed with the Securities and Exchange Commission pursuant to the 1933 Act (an “IPO”) and then only to the extent that the Shares subject to this Option (as adjusted per above) shall have vested in accordance with the following vesting schedule:
Vesting Schedule:	25% of the Shares (as adjusted per above) will vest and become exercisable on the first anniversary of the Date of Grant, and the remaining 75% of the Shares (as adjusted per above) shall vest and become exercisable in equal monthly installments over the 36 months following the first anniversary of the Date of Grant; provided that in the event of a Change in Control 12 months of this vesting schedule shall be accelerated.
Expiration Date:	10 year anniversary of Date of Grant

This Option is intended to be treated as an Incentive Stock Option under section 422 of the Internal Revenue Code of 1986, as amended (the “Code”). By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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INCENTIVE STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Incentive Stock Option Certificate to which this Incentive Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”) (the “Plan”); and

WHEREAS, the Company and the Optionee understand that this Option is intended to provide Optionee with a certain minimum total option holdings in connection with a potential IPO and that the number of Shares that may become exercisable hereunder will be subject to both an IPO-based reduction and a time-based vesting schedule; and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be an Incentive Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate. As used herein, the term “Common Stock Deemed Outstanding” means, at any given time, the sum of (i) the number of shares of Common Stock actually outstanding at such time, (ii) the number of shares of Common Stock issuable upon conversion of any shares of the Company’s preferred stock actually outstanding at such time and (iii) the number of shares of Common Stock issuable upon the exercise in full of all Convertible Securities whether or not the Convertible Securities are convertible into Common Stock at such time, but shall exclude any shares of Common Stock or

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Convertible Securities in the treasury of the Corporation or held for the account of the Corporation or any of its subsidiaries. As used herein, the term “Convertible Securities” means securities or obligations that are exercisable for, convertible into or exchangeable for shares of Common Stock. The term includes options, warrants or other rights to subscribe for or purchase Common Stock or to subscribe for or purchase other securities that are convertible into, directly or indirectly, or exchangeable for Common Stock. The term also includes promissory notes that are convertible into or exchangeable for Common Stock upon the consummation of an IPO. Notwithstanding the foregoing, for purposes of determining the Target Percentage, no options issued and outstanding under the Plan shall be included in the calculation of the Common Stock Deemed Outstanding.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan. If the Optionee ceases to be an employee of the Company or of an Affiliate (for any reason other than the death or Disability of the Optionee or termination by the Optionee’s employer for Cause), the Option may be exercised to the extent then vested at termination, if it has not previously terminated, within ninety (90) days after the date the Optionee ceases to be an employee of the Company or an Affiliate, at such time as may be specified by the Board at or after the time of grant or within the originally prescribed term of the Option, whichever is earlier, but may not be exercised thereafter

In the event the Optionee’s employment is terminated by the Optionee’s employer for Cause, the Optionee’s right to exercise any unexercised portion of this Option shall cease as of such termination, and this Option shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Optionee’s termination as an employee, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Optionee’s termination, the Optionee engaged in conduct which would constitute Cause, then the Optionee shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

In the event of the Disability of the Optionee, as determined in accordance with the Plan, or if the Optionee is determined to be disabled under the Company’s long-term disability plan, the Option shall be exercisable to the extent then vested at Disability within one (1) year after the termination of Optionee’s employment or, if earlier, within the term originally prescribed by the Option.

In the event of the death of the Optionee while an employee of the Company or of an Affiliate, the Option shall be exercisable to the extent vested at death by the Optionee’s Survivors within one (1) year after the date of death of the Optionee or, if earlier, within the originally prescribed term of the Option.

In the event of a Change in Control (other than an IPO), this Option shall thereupon terminate. For purposes of this Agreement, “Change in Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which is a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other

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acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized for its general corporate purposes (including without limitation the retirement or repayment of outstanding debt obligations), or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person. “Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

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6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

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11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. NO OBLIGATION TO EMPLOY. The Company is not by the Plan or this Option obligated to continue the Optionee as an employee of the Company.

13. OPTION IS INTENDED TO BE AN INCENTIVE STOCK OPTION. The parties each intend that the Option be an Incentive Stock Option so that the Optionee (or in the event of Optionee’s death, Optionee’s legal representatives and/or any person who acquired Optionee’s rights to an Option in accordance with Section 7 hereof) may qualify for the favorable tax treatment provided to holders of Options that meet the standards of Section 422 of the Code. Nonetheless, if all or any part of the Option is determined not to be an Incentive Stock Option, the Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the

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Optionee’s own tax advisors regarding the tax effects of the Option and the requirements necessary to obtain favorable tax treatment under Section 422 of the Code, including, but not limited to, holding period requirements.

14. NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION. The Optionee agrees to notify the Company in writing immediately after the Optionee makes a Disqualifying Disposition of any of the Shares acquired pursuant to the exercise of the Option. A Disqualifying Disposition is defined in Section 424(c) of the Code and includes any disposition (including any sale) of such Shares before the later of (a) two years after the date the Optionee was granted the Option or (b) one year after the date the Optionee acquired Shares by exercising the Option, except as otherwise provided in Section 424(c) of the Code. If the Optionee has died before the Shares are sold, these holding period requirements do not apply and no Disqualifying Disposition can occur thereafter.

15. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 15.

16. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

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or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

17. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

18. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

19. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

20. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 21 below.

21. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF INCENTIVE STOCK OPTION

[Form For Unregistered Shares]

To: Aspen Aerogels, Inc.

30 Forbes Road, Bldg B

Northborough, MA 01532

Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Incentive Stock Option to purchase             shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Incentive Stock Option Agreement between the undersigned and the Company dated as of             , 201[  ].

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                     

Please issue the stock certificate for the Shares in the name of                     , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                    .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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EX-10.1.5

Exhibit 10.1.5

NQSO-[    ] [            ] Shares

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through December 18, 2013)

Non-Qualified Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Non-Qualified Stock Option Agreement (the “Agreement”) attached to this Non-Qualified Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:
Purchase Price:	$[    ] per share
Date of Grant:	, 201[    ]
Exercisability Schedule:	The Options shall vest and become exercisable in accordance with the following vesting schedule:
	25% of the Shares will vest and become exercisable on the first anniversary of the Date of Grant, and the remaining 75% of the Shares shall vest and become exercisable in equal monthly installments over the 36 months following the first anniversary of the Date of Grant; provided that in the event of a Change in Control 12 months of this vesting schedule shall be accelerated.
Expiration Date:	10 year anniversary of Date of Grant

By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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NON-QUALIFIED STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Non-Qualified Stock Option Certificate to which this Non-Qualified Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”) (the “Plan”); and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be a Non-Qualified Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION; TERMINATION OF PRIOR OPTIONS. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan. If the Optionee ceases to be an employee of the Company or of an Affiliate (for any reason other than the death or Disability of the Optionee or termination by the Optionee’s employer for Cause), the Option may be exercised to the extent then vested at termination, if it has not previously terminated, within ninety (90) days after the date the Optionee ceases to be an employee of the Company or an Affiliate, at such time as may be specified by the Board at or after the time of grant or within the originally prescribed term of the Option, whichever is earlier, but may not be exercised thereafter

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In the event the Optionee’s employment is terminated by the Optionee’s employer for Cause, the Optionee’s right to exercise any unexercised portion of this Option shall cease as of such termination, and this Option shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Optionee’s termination as an employee, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Optionee’s termination, the Optionee engaged in conduct which would constitute Cause, then the Optionee shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

In the event of the Disability of the Optionee, as determined in accordance with the Plan, or if the Optionee is determined to be disabled under the Company’s long-term disability plan, the Option shall be exercisable to the extent then vested at Disability within one (1) year after the termination of Optionee’s employment or, if earlier, within the term originally prescribed by the Option.

In the event of the death of the Optionee while an employee of the Company or of an Affiliate, the Option shall be exercisable to the extent vested at death by the Optionee’s Survivors within one (1) year after the date of death of the Optionee or, if earlier, within the originally prescribed term of the Option.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment

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duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such

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person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. NO OBLIGATION TO EMPLOY. The Company is not by the Plan or this Option obligated to continue the Optionee as an employee of the Company.

13. OPTION IS INTENDED TO BE A NON-QUALIFIED STOCK OPTION. The parties each intend that the Option be a Non-Qualified Stock Option. The Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option.

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14. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 14.

15. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

16. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

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17. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

18. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

19. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 20 below.

20. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

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EXHIBIT A

NOTICE OF EXERCISE OF NON-QUALIFIED STOCK OPTION

[Form For Unregistered Shares]

To:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Non-Qualified Stock Option to purchase             shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Non-Qualified Stock Option Agreement between the undersigned and the Company dated as of                 , 201[    ].

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                             

Please issue the stock certificate for the Shares in the name of                             , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                            .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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EX-10.1.6

Exhibit 10.1.6

2013 (Re-Pricing) NQSO-[    ] [            ] Shares                    

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through August 7, 2013)

Non-Qualified Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through August 7, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Non-Qualified Stock Option Agreement (the “Agreement”) attached to this Non-Qualified Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:
Purchase Price:	$0.09 per share
Date of Grant:	, 2013
Exercisability Schedule:	The Options shall vest and become exercisable in accordance with the following vesting schedule:
	40% of the Shares will vest and become exercisable on the Date of Grant, and the remaining 60% of the Shares shall vest and become exercisable in equal monthly installments over the 36 months following the Date of Grant; provided that in the event of a Change in Control 12 months of this vesting schedule shall be accelerated.
Expiration Date:	10 year anniversary of Date of Grant

By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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NON-QUALIFIED STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Non-Qualified Stock Option Certificate to which this Non-Qualified Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through August 7, 2013 (the “Plan”) (the “Plan”); and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be a Non-Qualified Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION; TERMINATION OF PRIOR OPTIONS. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan. Any and all options to purchase any capital securities of the Company that were granted to the Optionee prior to the date hereof, and the agreements entered into in connection therewith, if any, are hereby terminated and cancelled by the Company and the Optionee.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan. If the Optionee ceases to be an employee of the Company or of an Affiliate (for any reason other than the death or Disability of the Optionee or termination by the Optionee’s employer for Cause), the Option may be exercised to the extent then vested at termination, if it has not previously terminated, within ninety (90) days after the date the Optionee ceases to be an employee of the Company or an Affiliate, at such time as may be specified by the Board at or after the time of grant or within the originally prescribed term of the Option, whichever is earlier, but may not be exercised thereafter

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In the event the Optionee’s employment is terminated by the Optionee’s employer for Cause, the Optionee’s right to exercise any unexercised portion of this Option shall cease as of such termination, and this Option shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Optionee’s termination as an employee, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Optionee’s termination, the Optionee engaged in conduct which would constitute Cause, then the Optionee shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

In the event of the Disability of the Optionee, as determined in accordance with the Plan, or if the Optionee is determined to be disabled under the Company’s long-term disability plan, the Option shall be exercisable to the extent then vested at Disability within one (1) year after the termination of Optionee’s employment or, if earlier, within the term originally prescribed by the Option.

In the event of the death of the Optionee while an employee of the Company or of an Affiliate, the Option shall be exercisable to the extent vested at death by the Optionee’s Survivors within one (1) year after the date of death of the Optionee or, if earlier, within the originally prescribed term of the Option.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

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(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due

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from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. NO OBLIGATION TO EMPLOY. The Company is not by the Plan or this Option obligated to continue the Optionee as an employee of the Company.

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13. OPTION IS INTENDED TO BE A NON-QUALIFIED STOCK OPTION. The parties each intend that the Option be a Non-Qualified Stock Option. The Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option.

14. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 14.

15. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

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16. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

17. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

18. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

19. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 21 below.

20. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF NON-QUALIFIED STOCK OPTION

[Form For Unregistered Shares]

To: Aspen Aerogels, Inc.

30 Forbes Road, Bldg B

Northborough, MA 01532

Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Non-Qualified Stock Option to purchase             shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Non-Qualified Stock Option Agreement between the undersigned and the Company dated as of                 , 2013.

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                     

Please issue the stock certificate for the Shares in the name of                     , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                    .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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EX-10.1.7

Exhibit 10.1.7

(IPO) NQSO-[    ] [            ] Shares

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through December 18, 2013)

Non-Qualified Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Non-Qualified Stock Option Agreement (the “Agreement”) attached to this Non-Qualified Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:	(subject to adjustment as set forth below)
Adjustment to Number of Shares:	Automatically upon the consummation of an IPO (as defined below), the number of Shares subject to this Option shall be reduced to a number of Shares, that when combined with the number of shares of Common Stock issuable under Optionee’s total option holdings (including this Option), shall be equal to [        ] percent (the “Target Percentage”) of the Common Stock Deemed Outstanding (as defined below) as of immediately prior to the consummation of the IPO and any balance of the Shares subject to this Option resulting from such reduction shall thereupon be forfeited by Optionee. If the number of Shares subject to this Option is insufficient to achieve the Target Percentage, the Company is under no obligation to grant additional options to Optionee. Common Stock Deemed Outstanding is defined in Section 3 of the Agreement.

Purchase Price:	$[            ] per share
Date of Grant:	, 201[    ]
Exercisability Schedule:	The Options shall vest and become exercisable only in the event that there shall occur the consummation of a public offering of the equity of the Company pursuant to a registration statement filed with the Securities and Exchange Commission pursuant to the 1933 Act (an “IPO”) and then only to the extent that the Shares subject to this Option (as adjusted per above) shall have vested in accordance with the following vesting schedule:
Vesting Schedule:	25% of the Shares (as adjusted per above) will vest and become exercisable on the first anniversary of the Date of Grant, and the remaining 75% of the Shares (as adjusted per above) shall vest and become exercisable in equal monthly installments over the 36 months following the first anniversary of the Date of Grant; provided that in the event of a Change in Control 12 months of this vesting schedule shall be accelerated.
Expiration Date:	10 year anniversary of Date of Grant

By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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NON-QUALIFIED STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Non-Qualified Stock Option Certificate to which this Non-Qualified Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”) (the “Plan”); and

WHEREAS, the Company and the Optionee understand that this Option is intended to provide Optionee with a certain minimum total option holdings in connection with a potential IPO and that the number of Shares that may become exercisable hereunder will be subject to both an IPO-based reduction and a time-based vesting schedule; and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be a Non-Qualified Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate. As used herein, the term “Common Stock Deemed Outstanding” means, at any given time, the sum of (i) the number of shares of Common Stock actually outstanding at such time, (ii) the number of shares of Common Stock issuable upon conversion of any shares of the Company’s preferred stock actually outstanding at such time and (iii) the number of shares of Common Stock issuable upon the exercise in full of all Convertible Securities whether or not the Convertible Securities are convertible into Common Stock at such time, but shall exclude any shares of Common Stock or

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Convertible Securities in the treasury of the Corporation or held for the account of the Corporation or any of its subsidiaries. As used herein, the term “Convertible Securities” means securities or obligations that are exercisable for, convertible into or exchangeable for shares of Common Stock. The term includes options, warrants or other rights to subscribe for or purchase Common Stock or to subscribe for or purchase other securities that are convertible into, directly or indirectly, or exchangeable for Common Stock. The term also includes promissory notes that are convertible into or exchangeable for Common Stock upon the consummation of an IPO. Notwithstanding the foregoing, for purposes of determining the Target Percentage, no options issued and outstanding under the Plan shall be included in the calculation of the Common Stock Deemed Outstanding.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan. If the Optionee ceases to be an employee of the Company or of an Affiliate (for any reason other than the death or Disability of the Optionee or termination by the Optionee’s employer for Cause), the Option may be exercised to the extent then vested at termination, if it has not previously terminated, within ninety (90) days after the date the Optionee ceases to be an employee of the Company or an Affiliate, at such time as may be specified by the Board at or after the time of grant or within the originally prescribed term of the Option, whichever is earlier, but may not be exercised thereafter

In the event the Optionee’s employment is terminated by the Optionee’s employer for Cause, the Optionee’s right to exercise any unexercised portion of this Option shall cease as of such termination, and this Option shall thereupon terminate. Notwithstanding anything herein to the contrary, if subsequent to the Optionee’s termination as an employee, but prior to the exercise of the Option, the Board determines that, either prior or subsequent to the Optionee’s termination, the Optionee engaged in conduct which would constitute Cause, then the Optionee shall immediately cease to have any right to exercise the Option and this Option shall thereupon terminate.

In the event of the Disability of the Optionee, as determined in accordance with the Plan, or if the Optionee is determined to be disabled under the Company’s long-term disability plan, the Option shall be exercisable to the extent then vested at Disability within one (1) year after the termination of Optionee’s employment or, if earlier, within the term originally prescribed by the Option.

In the event of the death of the Optionee while an employee of the Company or of an Affiliate, the Option shall be exercisable to the extent vested at death by the Optionee’s Survivors within one (1) year after the date of death of the Optionee or, if earlier, within the originally prescribed term of the Option.

In the event of a Change in Control (other than an IPO), this Option shall thereupon terminate. For purposes of this Agreement, “Change in Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which is a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other

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acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized for its general corporate purposes (including without limitation the retirement or repayment of outstanding debt obligations), or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person. “Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

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6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

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11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. NO OBLIGATION TO EMPLOY. The Company is not by the Plan or this Option obligated to continue the Optionee as an employee of the Company.

13. OPTION IS INTENDED TO BE A NON-QUALIFIED STOCK OPTION. The parties each intend that the Option be a Non-Qualified Stock Option. The Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option.

14. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities,

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not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 14.

15. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

16. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

17. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

18. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter

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hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

19. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 20 below.

20. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF NON-QUALIFIED STOCK OPTION

[Form For Unregistered Shares]

To: Aspen Aerogels, Inc.

30 Forbes Road, Bldg B

Northborough, MA 01532

Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Non-Qualified Stock Option to purchase             shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Non-Qualified Stock Option Agreement between the undersigned and the Company dated as of                 , 201[    ].

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                            

Please issue the stock certificate for the Shares in the name of                             , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                            .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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EX-10.1.8

Exhibit 10.1.8

2013 (Re-Pricing Director) NQSO-[    ] [            ] Shares                    

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through December 18, 2013)

Non-Qualified Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Non-Qualified Stock Option Agreement (the “Agreement”) attached to this Non-Qualified Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:
Purchase Price:	$0.18 per share
Date of Grant:	December 20, 2013
Vesting Start Date:	August 7, 2013
Exercisability Schedule:	The Options shall vest and become exercisable in accordance with the following vesting schedule:
	40% of the Shares will vest and become exercisable retroactive to the Vesting Start Date, and the remaining 60% of the Shares shall vest and become exercisable in equal monthly installments over the 36 months following the Vesting Start Date; provided that (i) in the event of a Change in Control, (ii) if the Optionee shall be removed by the shareholders as a director of the Company other than for Cause or (iii) if, at any time prior to the consummation by the Company of a public offering of its securities, the Optionee is not re-elected as a director of the Company by its shareholders, 100% of the then

	unvested Shares shall vest and become exercisable; and provided further that in each such case, such person continues to serve as a director of the Company as of the applicable vesting (or acceleration of vesting) date.
Expiration Date:	10 year anniversary of Date of Grant

By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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NON-QUALIFIED STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Non-Qualified Stock Option Certificate to which this Non-Qualified Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”); and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be a Non-Qualified Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION; TERMINATION OF PRIOR OPTIONS. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan. Any and all options to purchase any capital securities of the Company that were granted to the Optionee prior to the date hereof, and the agreements entered into in connection therewith, if any, are hereby terminated and cancelled by the Company and the Optionee.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the

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form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

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8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE

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SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. RESTRICTIONS ON TRANSFER OF SHARES.

(a) The Shares acquired by the Optionee pursuant to the exercise of the Option granted hereby shall not be transferred by the Optionee except as permitted under the terms of the Sixth Amended and Restated Stockholders’ Agreement among the Company and the Stockholders (as defined therein) dated as of March 28, 2013, and all amendments, modifications, substitutions and replacements thereto (the “Stockholders’ Agreement”). The Optionee agrees to become a party to the Stockholders’ Agreement upon acquiring any Shares by exercise of the Option.

(b) The Optionee acknowledges and agrees that neither the Company, its shareholders nor its directors and officers, has any duty or obligation to disclose to the Optionee any material information regarding the business of the Company or affecting the value of the Shares before, at the time of, or following a termination of the Optionee’s relationship with the Company or an Affiliate by the Company or such Affiliate, including, without limitation, any information concerning plans for the Company to make a public offering of its securities or to be acquired by or merged with or into another firm or entity.

13. NO OBLIGATION TO RETAIN AS A DIRECTOR. The Company is not by the Plan or this Option obligated to continue the Optionee as a director of the Company.

14. OPTION IS INTENDED TO BE A NON-QUALIFIED STOCK OPTION. The parties each intend that the Option be a Non-Qualified Stock Option. The Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option.

15. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier

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than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 15.

16. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

17. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

18. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

19. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

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20. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 21 below.

21 WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF NON-QUALIFIED STOCK OPTION

[Form For Unregistered Shares]

To: Aspen Aerogels, Inc.

30 Forbes Road, Bldg B

Northborough, MA 01532

Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Non-Qualified Stock Option to purchase              shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Non-Qualified Stock Option Agreement between the undersigned and the Company dated as of                     , 2013.

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I understand the terms and restrictions on the right to dispose of the Shares set forth in the 2001 Equity Incentive Plan, the Non-Qualified Stock Option Agreement and the Sixth Amended and Restated Stockholders’ Agreement among the Company and the Stockholders (as defined therein) dated as of March 28, 2013, and all amendments, modifications, substitutions and replacements thereto (the “Stockholders’ Agreement”), all of which I have carefully reviewed. I agree to become a party to the Stockholders’ Agreement by executing the Joinder attached hereto as Annex 1. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                             

Please issue the stock certificate for the Shares in the name of                             , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                            .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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ANNEX 1

JOINDER TO SIXTH AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT OF

ASPEN AEROGELS, INC.

As of                  ,         

The undersigned,                             , having a principal business address of                             , hereby acknowledges that the undersigned has become a Stockholder of Aspen Aerogels, Inc., a Delaware corporation (the “Company”), as of the date first written above, and hereby joins in the execution of that certain Sixth Amended and Restated Stockholders’ Agreement of the Company, dated as of March 28, 2013 (together with all amendments, modifications, substitutions and replacements thereto the “Stockholders Agreement”).

By executing this Joinder, the undersigned hereby:

1. Agrees and acknowledges that the undersigned is a Stockholder of the Company, as such term is defined and used in the Stockholders Agreement, a copy of which has been furnished to the undersigned, with the same force and effect as if originally named therein as a Stockholder and that each reference to a Stockholder in the Stockholders Agreement shall be deemed to include the undersigned; and

2. Agrees to be bound by, and agrees that the undersigned is bound by, all of the terms and provisions of the Stockholders Agreement for all purposes.

Name:

Title:

ACKNOWLEDGED AND ACCEPTED:

ASPEN AEROGELS, INC.

By:

Name:

Title:

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EX-10.1.9

Exhibit 10.1.9

2013 (IPO Director) NQSO-[    ] [            ] Shares                    

Aspen Aerogels, Inc.

2001 Equity Incentive Plan

(as amended through December 18, 2013)

Non-Qualified Stock Option Certificate

Aspen Aerogels, Inc., a Delaware corporation (the “Company”), hereby grants to the person named below (the “Optionee”) an option (the “Option”) to purchase shares of its Common Stock (the “Shares”) under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”), exerciseable on the following terms and conditions and those set forth in the Non-Qualified Stock Option Agreement (the “Agreement”) attached to this Non-Qualified Stock Option Certificate (this “Certificate”).

Name of Optionee:
Address:
Social Security Number:
Number of Shares:	(subject to adjustment as set forth below)
Adjustment to Number of Shares:	Automatically upon the consummation of an IPO (as defined below), the number of Shares subject to this Option shall be reduced to a number of Shares, that when combined with the number of shares of Common Stock issuable under Optionee’s total option holdings (including this Option), shall be equal to [        ] percent (the “Target Percentage”) of the Common Stock Deemed Outstanding (as defined below) as of immediately prior to the consummation of the IPO and any balance of the Shares subject to this Option resulting from such reduction shall thereupon be forfeited by Optionee. If the number of Shares subject to this Option is insufficient to achieve the Target Percentage, the Company is under no obligation to grant additional options to Optionee. Common Stock Deemed Outstanding is defined in Section 3 of the Agreement.

Purchase Price:	$0.18 per share
Date of Grant:	December 20, 2013
Vesting Start Date:	August 7, 2013
Exercisability Schedule:	The Options shall vest and become exercisable only in the event that there shall occur the consummation of a public offering of the equity of the Company pursuant to a registration statement filed with the Securities and Exchange Commission pursuant to the 1933 Act (an “IPO”) and then only to the extent that the Shares subject to this Option (as adjusted per above) shall have vested in accordance with the following vesting schedule:
Vesting Schedule:	40% of the Shares (as adjusted per above) will vest and become exercisable retroactive to the Vesting Start Date, and the remaining 60% (as adjusted per above) of the Shares shall vest and become exercisable in equal monthly installments over the 36 months following the Vesting Start Date; provided that (i) in the event of a Change in Control, (ii) if the Optionee shall be removed by the shareholders as a director of the Company other than for Cause or (iii) if, at any time prior to the consummation by the Company of the IPO, the Optionee is not re-elected as a director of the Company by its shareholders, 100% of the then unvested Shares shall vest and become exercisable; and provided further that in each such case, such person continues to serve as a director of the Company as of the applicable vesting (or acceleration of vesting) date.
Expiration Date:	10 year anniversary of Date of Grant

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By acceptance of this Option, the Optionee agrees to the terms and conditions set forth in this Certificate, the Agreement, and the Plan. This Certificate shall serve as the signature page of the Optionee and the Company to the Agreement.

OPTIONEE	ASPEN AEROGELS, INC.
	By:
Name:	Name:
	Title:

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NON-QUALIFIED STOCK OPTION AGREEMENT

ASPEN AEROGELS, INC.

AGREEMENT made as of the Date of Grant (as defined in the Non-Qualified Stock Option Certificate to which this Non-Qualified Stock Option Agreement is attached (the “Certificate”)) between Aspen Aerogels, Inc., a Delaware corporation (the “Company”), and the Optionee (as defined in the Certificate).

WHEREAS, the Company desires to grant to the Optionee an option (the “Option”) to purchase shares of its Common Stock (the “Shares”), under and for the purposes set forth in the Company’s 2001 Equity Incentive Plan, as amended through December 18, 2013 (the “Plan”); and

WHEREAS, the Company and the Optionee understand that this Option is intended to provide Optionee with a certain minimum total option holdings in connection with a potential IPO and that the number of Shares that may become exercisable hereunder will be subject to both an IPO-based reduction and a time-based vesting schedule; and

WHEREAS, the Company and the Optionee understand and agree that any terms used and not defined herein have the same meanings as in the Plan; and

WHEREAS, the Company and the Optionee each intend that the Option granted herein shall be a Non-Qualified Stock Option.

NOW, THEREFORE, in consideration of the mutual covenants hereinafter set forth and for other good and valuable consideration, the parties hereto agree as follows:

1. GRANT OF OPTION. The Company hereby grants to the Optionee the right and option to purchase all or any part of that number of Shares set forth in the Certificate, on the terms and conditions and subject to all the limitations set forth herein and in the Certificate and the Plan, which are incorporated herein by reference. The Optionee acknowledges receipt of a copy of the Certificate and the Plan.

2. PURCHASE PRICE. The purchase price of the Shares covered by the Option is set forth in the Certificate. Payment shall be made in accordance with Section 3c of the Plan.

3. EXERCISABILITY OF OPTION. Subject to the terms and conditions set forth in this Agreement and the Plan, the Option granted hereby shall become exercisable only with respect to Shares that have vested as set forth in the Certificate. As used herein, the term “Common Stock Deemed Outstanding” means, at any given time, the sum of (i) the number of shares of Common Stock actually outstanding at such time, (ii) the number of shares of Common Stock issuable upon conversion of any shares of the Company’s preferred stock actually outstanding at such time and (iii) the number of shares of Common Stock issuable upon the exercise in full of all Convertible Securities whether or not the Convertible Securities are convertible into Common Stock at such time, but shall exclude any shares of Common Stock or

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Convertible Securities in the treasury of the Corporation or held for the account of the Corporation or any of its subsidiaries. As used herein, the term “Convertible Securities” means securities or obligations that are exercisable for, convertible into or exchangeable for shares of Common Stock. The term includes options, warrants or other rights to subscribe for or purchase Common Stock or to subscribe for or purchase other securities that are convertible into, directly or indirectly, or exchangeable for Common Stock. The term also includes promissory notes that are convertible into or exchangeable for Common Stock upon the consummation of an IPO. Notwithstanding the foregoing, for purposes of determining the Target Percentage, no options issued and outstanding under the Plan shall be included in the calculation of the Common Stock Deemed Outstanding.

4. TERM OF OPTION. The Option shall terminate on the ten year anniversary from the Date of Grant (as defined in the Certificate), but shall be subject to earlier termination as provided herein or in the Plan.

In the event of a Change in Control (other than an IPO), this Option shall thereupon terminate. For purposes of this Agreement, “Change in Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which is a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized for its general corporate purposes (including without limitation the retirement or repayment of outstanding debt obligations), or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person. “Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

5. METHOD OF EXERCISING OPTION.

(a) Subject to the terms and conditions of this Agreement, the Option may be exercised by written notice to the Company at its principal executive office in substantially the form of Exhibit A attached hereto. Such notice shall state the number of Shares with respect to which the Option is being exercised and shall be signed by the person so exercising the Option. Payment of the purchase price for such Shares shall be made in accordance with Section 5d of the Plan. The Company shall deliver a certificate or certificates representing such Shares to the Escrow Agent as set forth below as soon as practicable after the notice shall be received, provided, however, that the Company may delay issuance of such Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including, without limitation, state securities or “blue sky” laws). The certificate or certificates for the Shares as to which the Option shall have been so exercised shall be registered

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in the name of the person or persons so exercising the Option (or, if the Option shall be exercised by the Optionee and if the Optionee shall so request in the notice exercising the Option, shall be registered in the name of the Optionee and another person jointly, with right of survivorship) and shall be delivered to the Escrow Agent as provided below. In the event the Option shall be exercised, pursuant to Section 5 hereof, by any person or persons other than the Optionee, such notice shall be accompanied by appropriate proof of the right of such person or persons to exercise the Option. All Shares that shall be purchased upon the exercise of the Option as provided herein shall be fully paid and nonassessable.

(b) As security for the faithful performance of the terms of this Agreement and to insure the availability for delivery of the Optionee’s Shares pursuant to this Agreement, the Optionee agrees to deliver to and deposit with the Secretary of the Company, or such other person designated by the Company, as escrow agent (the “Escrow Agent”), a stock assignment duly endorsed (with date and number of Shares in blank) in the form prescribed by the Escrow Agent together with any certificate or certificates evidencing Shares. The Escrow Agent shall hold such documents in escrow pursuant to the terms of this Agreement, including without limitation this Section 5(b).

6. PARTIAL EXERCISE. Exercise of this Option to the extent above stated may be made in part at any time and from time to time within the above limits, except that no fractional share shall be issued pursuant to this Option.

7. NON-ASSIGNABILITY. The Option shall not be transferable by the Optionee other than (i) by will or by the laws of descent and distribution, (ii) to such Optionee’s spouse or children (or step-children) or to a trust the sole beneficiaries of which are the Optionee’s spouse and/or children (or step-children), provided that all voting rights with respect to any Shares remain with the Optionee, or (iii) to irrevocable trusts or other estate planning entities for tax or estate planning purposes; provided that in each case the transferee(s) shall hold the Option or any Shares subject to the same restrictions applicable hereunder to the Optionee and shall agree in writing to be bound by the terms of the Stockholders’ Agreement. Except as provided in the preceding sentence, the Option shall be exercisable, during the Optionee’s lifetime, only by the Optionee (or, in the event of legal incapacity or incompetency, by the Optionee’s guardian or representative) and shall not be assigned, pledged or hypothecated in any way (whether by operation of law or otherwise) and shall not be subject to execution, attachment or similar process. Any attempted transfer, assignment, pledge, hypothecation or other disposition of the Option or of any rights granted hereunder contrary to the provisions of this Section 7, or the levy of any attachment or similar process upon the Option shall be null and void.

8. NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Optionee shall have no rights as a stockholder with respect to Shares subject to this Agreement until registration of the Shares in the Company’s share register in the name of the Optionee. Except as is expressly provided in the Plan with respect to certain changes in the capitalization of the Company, no adjustment shall be made for dividends or similar rights for which the record date is prior to the date of such registration.

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9. CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions covering the treatment of Options in a number of contingencies such as stock splits and mergers. Provisions in the Plan for adjustment with respect to stock subject to Options and the related provisions with respect to successors to the business of the Company are hereby made applicable hereunder and are incorporated herein by reference.

10. TAXES. The Optionee acknowledges that upon exercise of the Option the Optionee will be deemed to have taxable income measured by the difference between the then fair market value of the Shares received upon exercise and the price paid for such Shares pursuant to this Agreement. The Optionee acknowledges that any income or other taxes due from him or her with respect to this Option or the Shares issuable pursuant to this Option shall be the Optionee’s responsibility. In the event the Option is exercised, the Company may withhold from the Optionee’s remuneration, if any, the minimum required federal, state and local withholding taxes attributable to such amount that is considered compensation includable in such person’s gross income. At the Company’s discretion, the amount required to be withheld may be withheld in cash from such remuneration, or in kind from the Shares otherwise deliverable to the Optionee on exercise of the Option. The Optionee further agrees that, if the Company does not withhold an amount from the Optionee’s remuneration sufficient to satisfy the Company’s income tax withholding obligation, the Optionee will reimburse the Company on demand, in cash, for the amount under-withheld.

11. PURCHASE FOR INVESTMENT. Unless the offering and sale of the Shares to be issued upon the particular exercise of the Option shall have been effectively registered under the Securities Act of 1933, as now in force or hereafter amended (the “1933 Act”), the Company shall be under no obligation to issue the Shares covered by such exercise unless and until the following conditions have been fulfilled:

(a) The person(s) who exercise the Option shall warrant to the Company, at the time of such exercise, that such person(s) are acquiring such Shares for their own respective accounts, for investment, and not with a view to, or for sale in connection with, the distribution of any such Shares, in which event the person(s) acquiring such Shares shall be bound by the provisions of the following legend which shall be endorsed upon the certificate(s) evidencing the Shares issued pursuant to such exercise:

“THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE BEEN TAKEN FOR INVESTMENT AND THEY MAY NOT BE SOLD OR OTHERWISE TRANSFERRED BY ANY PERSON, INCLUDING A PLEDGEE, UNLESS (1) EITHER (A) A REGISTRATION STATEMENT WITH RESPECT TO SUCH SHARES SHALL BE EFFECTIVE UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR (B) THE COMPANY SHALL HAVE RECEIVED AN OPINION OF COUNSEL SATISFACTORY TO IT THAT AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT IS THEN AVAILABLE, AND (2) THERE SHALL HAVE BEEN COMPLIANCE WITH ALL APPLICABLE STATE SECURITIES LAWS;” and

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(b) If the Company so requires, the Company shall have received an opinion of its counsel that the Shares may be issued upon such particular exercise in compliance with the 1933 Act without registration thereunder. Without limiting the generality of the foregoing, the Company may delay issuance of the Shares until completion of any action or obtaining of any consent, which the Company deems necessary under any applicable law (including without limitation state securities or “blue sky” laws).

12. RESTRICTIONS ON TRANSFER OF SHARES.

(a) The Shares acquired by the Optionee pursuant to the exercise of the Option granted hereby shall not be transferred by the Optionee except as permitted under the terms of the Sixth Amended and Restated Stockholders’ Agreement among the Company and the Stockholders (as defined therein) dated as of March 28, 2013, and all amendments, modifications, substitutions and replacements thereto (the “Stockholders’ Agreement”). The Optionee agrees to become a party to the Stockholders’ Agreement upon acquiring any Shares by exercise of the Option.

(b) The Optionee acknowledges and agrees that neither the Company, its shareholders nor its directors and officers, has any duty or obligation to disclose to the Optionee any material information regarding the business of the Company or affecting the value of the Shares before, at the time of, or following a termination of the Optionee’s relationship with the Company or an Affiliate by the Company or such Affiliate, including, without limitation, any information concerning plans for the Company to make a public offering of its securities or to be acquired by or merged with or into another firm or entity.

13. NO OBLIGATION TO RETAIN AS A DIRECTOR. The Company is not by the Plan or this Option obligated to continue the Optionee as a director of the Company.

14. OPTION IS INTENDED TO BE A NON-QUALIFIED STOCK OPTION. The parties each intend that the Option be a Non-Qualified Stock Option. The Optionee understands that neither the Company nor any Affiliate is responsible to compensate him or her or otherwise make up for the treatment of the Option as a Non-qualified Stock Option and not as an Incentive Stock Option. The Optionee should consult with the Optionee’s own tax advisors regarding the tax effects of the Option.

15. HOLDBACK AGREEMENT. The Optionee agrees, if so requested by the managing underwriter in each underwritten registration of the Company’s capital stock or other securities, not to effect (except as part of such underwritten registration if included therein) any sale, distribution, short sale, loan, grant of options for the purchase of, or otherwise dispose of, any Shares for such period as such underwriter requests, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. If the managing underwriter advises the Company that, in its opinion, no sale, distribution, short sale, loan, grant of options for the purchase of, or after disposition of, any shares of the Company’s common stock should be effected for a period of not more than 180 days after the effective date of such underwritten registration in order to complete the sale and distribution of the securities included therein and the Company gives notice to such effect to the

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Optionee, the Optionee shall not (except as part of such underwritten registration if included therein) effect any sale, distribution, short sale, loan, grant of options for the purchase of or otherwise dispose of shares of the Company’s common stock for such period as such managing underwriter advises, such period in no event to commence earlier than ten (10) days prior to, or to end more than 180 days after, the effective date of such registration. The Optionee further agrees that the Company may instruct its transfer agent to place stop transfer notations in its records to enforce the provisions of this Section 15.

16. NOTICES. Any notices required or permitted by the terms of this Agreement or the Plan shall be given by recognized courier service, facsimile, registered or certified mail, return receipt requested, addressed as follows:

If to the Company:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Telephone:	(508) 691-1111
	Facsimile:	(508) 691-1200
	Attention:	Chief Financial Officer
If to the Optionee:	At the address of the Optionee as set forth in the records of the Company

or to such other address or addresses of which notice in the same manner has previously been given. Any such notice shall be deemed to have been given upon the earlier of receipt, one business day following delivery to a recognized courier service or five (5) business days following mailing by registered or certified mail.

17. GOVERNING LAW. This Agreement shall be construed and enforced in accordance with the law of the State of Delaware, without giving effect to the conflict of law principles thereof.

18. BENEFIT OF AGREEMENT. Subject to the provisions of the Plan and the other provisions hereof, this Agreement shall be for the benefit of and shall be binding upon the heirs, executors, administrators, successors and assigns of the parties hereto.

19. ENTIRE AGREEMENT. This Agreement, together with the Plan, embodies the entire agreement and understanding between the parties hereto with respect to the subject matter hereof and supersedes all prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant or agreement not expressly set forth in this Agreement shall affect or be used to interpret, change or restrict, the express terms and provisions of this Agreement, provided, however, in any event, this Agreement shall be subject to and governed by the Plan.

20. MODIFICATIONS AND AMENDMENTS. The terms and provisions of this Agreement may be modified or amended as provided in the Plan or in Section 21 below.

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21. WAIVERS AND CONSENTS. Except as provided in the Plan, the terms and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed by the party entitled to the benefits of such terms or provisions. Notwithstanding anything to the contrary in the preceding sentence, holders representing a majority of the Shares subject to an Option under the Plan may waive or grant a consent to the departure from the provisions of this Agreement so long as such waiver or consent applies to all holders of Shares subject to an Option under the Plan in the same fashion. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.

[remainder of page intentionally left blank]

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EXHIBIT A

NOTICE OF EXERCISE OF NON-QUALIFIED STOCK OPTION

[Form For Unregistered Shares]

To:	Aspen Aerogels, Inc.
	30 Forbes Road, Bldg B
	Northborough, MA 01532
	Attention: Chief Financial Officer

Ladies and Gentlemen:

I hereby exercise my Non-Qualified Stock Option to purchase             shares (the “Shares”) of the common stock, par value $.00001 per share, of Aspen Aerogels, Inc. (the “Company”) at the exercise price of $[            ] per share, pursuant to and subject to the terms of that certain Non-Qualified Stock Option Agreement between the undersigned and the Company dated as of                 , 2013.

I am aware that the Shares have not been registered under the Securities Act of 1933, as amended (the “1933 Act”), or any state securities laws. I understand that the reliance by the Company on exemptions under the 1933 Act is predicated in part upon the truth and accuracy of the statements by me in this Notice of Exercise.

I hereby represent and warrant that (1) I have been furnished with all information which I deem necessary to evaluate the merits and risks of the purchase of the Shares; (2) I have had the opportunity to ask questions concerning the Shares and the Company and all questions posed have been answered to my satisfaction; (3) I have been given the opportunity to obtain any additional information I deem necessary to verify the accuracy of any information obtained concerning the Shares and the Company; and (4) I have such knowledge and experience in financial and business matters that I am able to evaluate the merits and risks of purchasing the Shares and to make an informed investment decision relating thereto.

I hereby represent and warrant that I am purchasing the Shares for my own personal account for investment and not with a view to the sale or distribution of all or any part of the Shares. I understand that because the Shares have not been registered under the 1933 Act, I must continue to bear the economic risk of the investment for an indefinite time and the Shares cannot be sold unless the Shares are subsequently registered under applicable federal and state securities laws or an exemption from such registration requirements is available.

I agree that I will in no event sell or distribute or otherwise dispose of all or any part of the Shares unless (1) there is an effective registration statement under the 1933 Act and applicable state securities laws covering any such transaction involving the Shares or (2) the Company receives an opinion of my legal counsel (concurred in by legal counsel for the Company) stating that such transaction is exempt from registration or the Company otherwise satisfies itself that such transaction is exempt from registration.

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I consent to the placing of a legend on my certificate for the Shares stating that the Shares have not been registered and setting forth the restriction on transfer contemplated hereby and to the placing of a stop transfer order on the books of the Company and with any transfer agents against the Shares until the Shares may be legally resold or distributed without restriction. I understand that at the present time Rule 144 of the Securities and Exchange Commission (the “SEC”) may not be relied on for the resale or distribution of the Shares by me. I understand that the Company has no obligation to me to register the sale of the Shares with the SEC and has not represented to me that it will register the sale of the Shares. I understand the terms and restrictions on the right to dispose of the Shares set forth in the 2001 Equity Incentive Plan, the Non-Qualified Stock Option Agreement and the Sixth Amended and Restated Stockholders’ Agreement among the Company and the Stockholders (as defined therein) dated as of March 28, 2013, and all amendments, modifications, substitutions and replacements thereto (the “Stockholders’ Agreement”), all of which I have carefully reviewed. I agree to become a party to the Stockholders’ Agreement by executing the Joinder attached hereto as Annex 1. I consent to the placing of a legend on my certificate for the Shares referring to such restrictions and the placing of stop transfer orders until the Shares may be transferred in accordance with the terms of such restrictions.

I have considered the Federal, state and local income tax implications of the exercise of my Option and the purchase and subsequent sale of the Shares.

I am paying the option exercise price for the Shares as follows:                             

Please issue the stock certificate for the Shares in the name of                             , and deliver to the Escrow Agent.

My mailing address for shareholder communications is:                            .

Very truly yours,

Optionee (signature)

Print Name

Date

Social Security Number

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ANNEX 1

JOINDER TO SIXTH AMENDED AND RESTATED STOCKHOLDERS’ AGREEMENT OF

ASPEN AEROGELS, INC.

As of                  ,         

The undersigned,                             , having a principal business address of                             , hereby acknowledges that the undersigned has become a Stockholder of Aspen Aerogels, Inc., a Delaware corporation (the “Company”), as of the date first written above, and hereby joins in the execution of that certain Sixth Amended and Restated Stockholders’ Agreement of the Company, dated as of March 28, 2013 (together with all amendments, modifications, substitutions and replacements thereto the “Stockholders Agreement”).

By executing this Joinder, the undersigned hereby:

1. Agrees and acknowledges that the undersigned is a Stockholder of the Company, as such term is defined and used in the Stockholders Agreement, a copy of which has been furnished to the undersigned, with the same force and effect as if originally named therein as a Stockholder and that each reference to a Stockholder in the Stockholders Agreement shall be deemed to include the undersigned; and

2. Agrees to be bound by, and agrees that the undersigned is bound by, all of the terms and provisions of the Stockholders Agreement for all purposes.

Name:

Title:

ACKNOWLEDGED AND ACCEPTED:

ASPEN AEROGELS, INC.

By:

Name:

Title:

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EX-10.3

Exhibit 10.3

LEASE

TMT 290 INDUSTRIAL PARK, INC.,

Landlord,

and

ASPEN AEROGELS, INC.,

Tenant

TABLE OF CONTENTS
1.	USE AND RESTRICTIONS ON USE	1
2.	TERM	4
3.	RENT	4
4.	RENT ADJUSTMENTS	5
5.	SECURITY DEPOSIT	7
6.	ALTERATIONS	9
7.	REPAIR	10
8.	LIENS	11
9.	ASSIGNMENT AND SUBLETTING	11
10.	INDEMNIFICATION	13
11.	INSURANCE	14
12.	WAIVER OF SUBROGATION	14
13.	SERVICES AND UTILITIES	14
14.	HOLDING OVER	14
15.	SUBORDINATION	15
16.	RULES AND REGULATIONS	15
17.	REENTRY BY LANDLORD	15
18.	DEFAULT	16
19.	REMEDIES	16
20.	TENANT’S BANKRUPTCY OR INSOLVENCY	19
21.	QUIET ENJOYMENT	19
22.	DAMAGE BY FIRE, ETC.	19
23.	EMINENT DOMAIN	21
24.	SALE BY LANDLORD	21
25.	ESTOPPEL CERTIFICATES	21
26.	SURRENDER OF PREMISES	21
27.	NOTICES	22
28.	TAXES PAYABLE BY TENANT	22
29.	RELOCATION OF TENANT	22
30.	DEFINED TERMS AND HEADINGS	22
31.	TENANT’S AUTHORITY	23

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32.	COMMISSIONS	23
33.	TIME AND APPLICABLE LAW	23
34.	SUCCESSORS AND ASSIGNS	23
35.	ENTIRE AGREEMENT	23
36.	EXAMINATION NOT OPTION	23
37.	RECORDATION	23
38.	RENT SCHEDULE	23
39.	RENEWAL OPTION	24
40.	PARKING AND LOADING	24
41.	LIMITATION OF LANDLORD’S LIABILITY	25
EXHIBIT A — PREMISES
EXHIBIT B — INITIAL ALTERATIONS
EXHIBIT C — RULES AND REGULATIONS		C-1
EXHIBIT D — HAZARDOUS MATERIALS EXHIBIT
EXHIBIT E — FORM OF LETTER OF CREDIT
EXHIBIT F — ROOFTOP LICENSE AGREEMENT		F-1

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MULTI-TENANT INDUSTRIAL NET LEASE

REFERENCE PAGE

BUILDING:	30 Forbes Road
	I-290 Industrial Park, Northborough, MA
LANDLORD:	TMT 290 INDUSTRIAL PARK, INC., a Delaware nonprofit corporation
LANDLORD’S ADDRESS:	c/o RREEF Management Company
	600 Unicorn Park Drive, Woburn, MA 01801
LEASE REFERENCE DATE:	August 20, 2001
TENANT:	ASPEN AEROGELS, INC., a Delaware corporation
TENANT’S ADDRESS:
(a) As of beginning of Term:	184 Cedar Hill Street, Marlborough, MA 10752
(b) Prior to beginning of Term
(if different):
PREMISES IDENTIFICATION:	Suite Number          (for outline of Premises see Exhibit A)
PREMISES RENTABLE AREA:	Approximately 31,119 sq. ft.
USE:	Manufacture of aerogel related products, and related storage and office. Tenant is responsible to obtain any necessary business licenses or permits.
SCHEDULED COMMENCEMENT DATE:	October 1, 2001
RENT COMMENCEMENT DATE:	October 15, 2001
TERMINATION DATE:	October 31, 2006
TERM OF LEASE:	Five (5) years and one (1) month beginning on the Commencement Date and ending on the Termination Date (unless sooner terminated pursuant to the Lease)
INITIAL ANNUAL RENT (Article 3):	See Rent Schedule, Article 38
INITIAL MONTHLY INSTALLMENT OF ANNUAL RENT (Article 3):	See Rent Schedule, Article 38
INITIAL ESTIMATED RENT ADJUSTMENTS (Article 4)	$1.70 psf/yr
TENANT’S PROPORTIONATE SHARE:	27.74%
SECURITY DEPOSIT:	Letter of Credit in initial amount of $171,154.50; see Article 5
ASSIGNMENT/SUBLETTING FEE	$750.00
REAL ESTATE BROKER DUE COMMISSION:	Spaulding & Slye Colliers and CB Richard Ellis/Whittier

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The Reference Page information is incorporated into and made a part of the Lease. In the event of any conflict between any Reference Page information and the Lease, the Lease shall control. This Lease includes Exhibits A through F, all of which are made a part of this Lease.

LANDLORD:		TENANT:
TMT 290 INDUSTRIAL PARK, INC., a Delaware nonprofit corporation		ASPEN AEROGELS, INC., a Delaware corporation
By:	RREEF Management Company, a Delaware corporation
By:	/s/ Eric Berke Eric Berke, District Manager	By:	/s/ Patrick J. Piper
		Title:	CFO
Dated:	10/11, 2001	Date:	10/9, 2001

iv

LEASE

By this Lease Landlord leases to Tenant and Tenant leases from Landlord the Premises in the Building as set forth and described on the Reference Page. The Reference Page, including all terms defined thereon, is incorporated as part of this Lease.

1. USE AND RESTRICTIONS ON USE.

1.1 The Premises are to be used solely for the purposes stated on the Reference Page. Tenant shall not do or permit anything to be done in or about the Premises which will in any way obstruct or interfere with the rights of other tenants or occupants of the Building or injure, annoy, or disturb them or allow the Premises to be used for any improper, immoral, unlawful, or objectionable purpose. Tenant shall not do, permit or suffer in, on, or about the Premises the sale of any alcoholic liquor without the written consent of Landlord first obtained, or the commission of any waste. Tenant shall comply with all governmental laws, ordinances and regulations applicable to the use of the Premises and its occupancy and shall promptly comply with all governmental orders and directions for the correction, prevention and abatement of any violations in or upon, or in connection with, the Premises, all at Tenant’s sole expense. Tenant shall not do or permit anything to be done on or about the Premises or bring or keep anything into the Premises which will in any way increase the rate of, invalidate or prevent the procuring of any insurance protecting against loss or damage to the Building or any of its contents by fire or other casualty or against liability for damage to property or injury to persons in or about the Building or any part thereof.

1.2 Hazardous Materials.

1.2.1 Tenant agrees that Tenant, its agents and contractors, licensees, or invitees shall not handle, use, manufacture, store or dispose of any flammables, explosives, radioactive materials, hazardous wastes or materials, toxic wastes or materials, or other similar substances, petroleum products or derivatives (collectively “Hazardous Materials”) on, under, or about the Premises, without Landlord’s prior written consent (which consent shall not be unreasonably withheld as long as Tenant demonstrates and documents to Landlord’s reasonable satisfaction (i) that such Hazardous Materials (A) are necessary or useful to Tenant’s business; and (B) will be used, kept, and stored in compliance with all laws relating to any Hazardous Materials so brought or used or kept in or about the Premises; and (ii) that Tenant will give all required notices concerning the presence in or on the Premises or the release of such Hazardous Materials from the Premises). In addition, without limiting Paragraph 1.2.3.1 below, and without the necessity of Landlord’s consent, Tenant may handle, store, use or dispose of products containing small quantities of Hazardous Materials, which products are of a type customarily found in offices and households (such as aerosol cans containing insecticides, toner for copies, paints, paint remover, and the like), provided that Tenant shall handle, store, use and dispose of any such Hazardous Materials in a safe and lawful manner and shall not allow such Hazardous Materials to contaminate the Premises or the environment.

1.2.2 Tenant further agrees that Tenant will not permit any substance to come into contact with groundwater under the Premises. Any such substance coming into contact with groundwater shall, regardless of its inherent hazardous characteristics, be considered a Hazardous Material for purposes of this Paragraph 1.2.

1.2.3

1.2.3.1 Notwithstanding the provisions of Paragraph 1.2.1, Tenant may at any time handle, store, and use Hazardous Materials, limited to the types, amounts, and use identified in the Hazardous Materials Exhibit D attached hereto. If no Hazardous Materials Exhibit is attached to this Lease, then this Paragraph 1.2.3.1 shall be of no force and effect. Tenant hereby certifies to Landlord that the information provided by Tenant pursuant to this Paragraph is true, correct, and complete. Tenant covenants to comply with the use restrictions shown on the attached Hazardous Materials Exhibit. Tenant’s business and operations, and more especially its handling, storage, use and disposal of Hazardous Materials shall at all times comply with all applicable laws pertaining to Hazardous Materials. Tenant shall secure and abide by all permits necessary for Tenant’s operations on the Premises. Tenant shall give or post all notices required by all applicable laws pertaining to Hazardous Materials. If Tenant shall at any time knowingly fail to comply with this Paragraph, Tenant shall immediately notify Landlord in writing of such noncompliance.

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1.2.3.2 Tenant shall provide Landlord with copies of any Material Safety Data Sheets (as required by the Occupational Safety and Health Act) relating to any Hazardous Materials to be used, kept, or stored at or on the Premises, at least 30 days prior to the first use, placement, or storage of such Hazardous Material on the Premises. Landlord shall have 10 days following delivery of such Material Safety Data Sheets to approve or forbid, in its sole discretion subject to the limitation contained in Paragraph 1.2 above, such use, placement, or storage of a Hazardous Material on the Premises. Landlord warrants that it has received Material Data Sheets for the Materials listed on the Hazardous Materials Exhibit and has approved such materials.

1.2.3.3 Tenant shall not store hazardous wastes on the Premises for more than 90 days; “hazardous waste” has the meaning given it by the Resource Conservation and Recovery Act of 1976, as amended. The forgoing restriction shall in no way impair or limit the Tenant’s ability to store the Hazardous Materials listed on Exhibit D on the Premises for any length of time during the Term, in compliance with all laws and regulations. Tenant shall not install any underground storage tanks on the Premises. Tenant shall not dispose of any Hazardous Material or solid waste on the Premises. It is agreed by Landlord that the Tenant will install storage containers or “storage tanks” for those Hazardous Materials listed on Exhibit D [Alterations], in compliance with all applicable statutes, codes and ordinances. In performing any alterations of the Premises permitted by the Lease, Tenant shall not install any Hazardous Material in the Premises without the specific consent of Landlord attached as an exhibit to this Lease.

1.2.3.4 Any increase in the premiums for necessary insurance on the Property which directly arises from Tenant’s use and/or storage of Hazardous Materials shall be solely at Tenant’s expense. Tenant shall procure and maintain at its sole expense such additional insurance as may be necessary to comply with any requirement of any Federal, State or local governmental agency with jurisdiction.

1.2.4 If Landlord, in its reasonable discretion, believes that the Premises or the environment have become contaminated with Hazardous Materials or similar materials that must be removed under the laws of the state where the Premises are located, in breach of the provisions of this Lease, Landlord, in addition to its other rights under this Lease, may enter upon the Premises and obtain samples from the Premises, including without limitation the soil and groundwater under the Premises, for the purposes of analyzing the same to determine whether and to what extent the Premises or the environment have become so contaminated. Tenant shall reimburse Landlord for the costs of any inspection, sampling and analysis that discloses contamination for which Tenant is liable under the terms of this Paragraph 1.2. Tenant may not perform any sampling, testing, or drilling to locate any Hazardous Materials on the Premises without Landlord’s prior written consent, not to be unreasonably withheld or delayed.

1.2.5 Without limiting the above, Tenant shall reimburse, defend, indemnify and hold Landlord harmless from and against any and all claims, losses, liabilities, damages, costs and expenses, including without limitation, loss of rental income, loss due to business interruption, and attorneys fees and costs, arising out of or in any way connected with the use, manufacture, storage, or disposal of Hazardous Materials by Tenant, its agents or contractors on, under or about the Premises including, without limitation, the costs of any required or necessary investigation, repair, cleanup or detoxification and the preparation of any closure or other required plans in connection herewith, whether voluntary or compelled by governmental authority. The indemnity obligations of Tenant under this clause shall survive any termination of the Lease. At Landlord’s option, Tenant shall perform any required or necessary investigation, repair, cleanup, or detoxification of the Premises. In such case, Landlord shall have the right, in its reasonable discretion, to approve all plans, consultants, and cleanup standards. Tenant shall provide Landlord on a timely basis with (i) copies of all documents, reports, and communications with governmental authorities; and (ii) notice and an opportunity to attend all meetings with regulatory authorities. Tenant shall comply with all notice requirements and Landlord and Tenant agree to cooperate with governmental authorities seeking access to the Premises for purposes of sampling or inspection. Absent Landlord’s gross negligence or willful misconduct, no disturbance of Tenant’s use of the Premises resulting from activities conducted pursuant to this Paragraph shall constitute an actual or constructive eviction of Tenant from the Premises. In the event that such cleanup extends beyond the termination of the Lease, Tenant’s obligation to pay rent (including additional rent and

2

percentage rent, if any) shall continue until (x) such cleanup is completed and any certificate of clearance or similar document has been delivered to Landlord, or (y) the Premises is re-leased and the replacement tenant has taken occupancy and has commenced the payment of rent, whichever is earlier. Rent during such holdover period shall be at market rent; if the parties are unable to agree upon the amount of such market rent, then Landlord shall have the option of (a) increasing the rent for the period of such holdover based upon the increase in the cost-of-living from the third month preceding the commencement date to the third month preceding the start of the holdover period, using such indices and assumptions and calculations as Landlord in its sole reasonable judgment shall determine are necessary; or (b) having Landlord and Tenant each appoint a qualified MAI appraiser doing business in the area; in turn, these two independent MAI appraisers shall appoint a third MAI appraiser and the majority shall decide upon the fair market rental for Premises as of the expiration of the then current term. Landlord and Tenant shall equally share in the expense of this appraisal except that in the event the rent is found to be within fifteen percent of the original rate quoted by Landlord, then Tenant shall bear the full cost of all the appraisal process. In no event shall the rent be subject to determination or modification by any person, entity, court, or authority other than as set forth expressly herein, and in no event shall the rent for any holdover period be less that the rent due in the preceding period.

1.2.6 Notwithstanding anything set forth in this Lease, Tenant shall only be responsible for contamination of Hazardous Materials or any cleanup resulting directly therefrom, resulting directly from matters occurring or Hazardous Materials deposited (other than by contractors, agents or representatives controlled by Landlord) during the Lease term as a result of the act of omission of Tenant, its agents, employees, representatives or contractors, and any other period of time during which Tenant is in actual or constructive occupancy of the Premises. Tenant shall take reasonable precautions to prevent the contamination of the Premise with Hazardous Materials by third parties.

1.2.7 It shall not be unreasonable for Landlord to withhold its consent to any proposed Assignment or Sublease if (i) the proposed Assignee’s or Sublessee’s anticipated use of the Premises involves the generation, storage, use, treatment or disposal of Hazardous Materials different from Tenant’s use; (ii) the proposed Assignee or Sublessee has been required by any prior landlord, lender, or governmental authority to take remedial action in connection with Hazardous Materials contaminating a property if the contamination resulted from such Assignee’s or Sublessee’s actions or use of the property in question; or (iii) the proposed Assignee or Sublessee is subject to a violation order issued by any governmental authority in connection with the use, disposal, or storage of a hazardous material.

1.2.8 Any of Tenant’s insurance insuring against claims of the type dealt with in this Paragraph 1.2 shall be considered primary coverage for claims against the Property arising out of or under this paragraph.

1.2.9 In the event of (i) any transfer of Tenant’s interest under this Lease; or (ii) the termination of this Lease, by lapse of time or otherwise, Tenant shall be solely responsible for compliance with any and all then effective federal, state or local laws concerning (i) the presence of hazardous or toxic materials in or on the Premises, Building, or Property (for example, the New Jersey Environmental Cleanup Responsibility Act, the Illinois Responsible Property Transfer Act, or similar applicable state laws), including but not limited to any reporting or filing requirements imposed by such laws. Tenant’s duty to pay rent, additional rent, and percentage rent shall continue until the obligations imposed by such laws are satisfied in full and any certificate of clearance or similar document has been delivered to Landlord.

1.2.10 All consents given by Landlord pursuant to this Paragraph 1.2 shall be in writing and shall be attached as amendments to this Lease.

1.2.11 Landlord represents to Tenant that, to Landlord’s knowledge, the Premises and Building do not contain any Hazardous Materials. The foregoing representation is wholly subject to and qualified by (i) any matters disclosed in any materials (e.g., existing environmental reports) made available by Landlord for Tenant’s inspection, (ii) any matters disclosed in any environmental reports or studies obtained by Tenant prior to the Commencement Date, and (iii) any other matters known to Tenant. “Landlord’s knowledge” means the actual knowledge, without duty of investigation, of the employees of Landlord’s property manager having day-to-day responsibility for the management and leasing of the Premises. The breach or inaccuracy of such representation shall in no event give rise to any right of termination.

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2. TERM.

2.1 The Term of this Lease shall begin on the date (“Commencement Date”) which shall be the later of the Scheduled Commencement Date as shown on the Reference Page or the date that Landlord shall tender possession of the Premises to Tenant. Landlord shall tender possession of the Premises free of any tenants or occupants and in broom clean condition, with all the work, if any, to be performed by Landlord pursuant to Exhibit B to this Lease substantially completed. Tenant shall deliver a punch list of items not completed within 30 days after Landlord tenders possession of the Premises and Landlord agrees to proceed with due diligence to perform its obligations regarding such items. Landlord and Tenant shall execute a memorandum setting forth the actual Commencement Date and Termination Date.

2.2 Tenant agrees that in the event of the inability of Landlord to deliver possession of the Premises on the Scheduled Commencement Date, Landlord shall not be liable for any damage resulting from such inability, but Tenant shall not be liable for any rent until the time when Landlord can, after notice to Tenant, deliver possession of the Premises to Tenant. No such failure to give possession on the Scheduled Commencement Date shall affect the other obligations of Tenant under this Lease, except that if Landlord is unable to deliver possession of the Premises within sixty (60) days of the Scheduled Commencement Date (other than as a result of strikes, shortages of materials or similar matters beyond the reasonable control of Landlord and Tenant is notified by Landlord in writing as to such delay), Tenant shall have the option to terminate this Lease unless said delay is as a result of: (a) Tenant’s failure to agree to plans and specifications; (b) Tenant’s request for materials, finishes or installations other than Landlord’s standard except those, if any, that Landlord shall have expressly agreed to furnish without extension of time agreed by Landlord; (c) Tenant’s change in any plans or specifications; or, (d) performance or completion by a party employed by Tenant. If any delay is the result of any of the foregoing, the Commencement Date and the payment of rent under this Lease shall be accelerated by the number of days of such delay.

2.3 In the event Landlord shall permit Tenant to occupy the Premises prior to the Commencement Date, such occupancy shall be subject to all the provisions of this Lease. Said early possession shall not advance the Termination Date.

3. RENT.

3.1 Effective as of the Rent Commencement Date, Tenant agrees to pay to Landlord the Annual Rent in effect from time to time by paying the Monthly Installment of Rent then in effect on or before the first day of each full calendar month during the Term, except that the first month’s rent shall be paid upon the execution of this Lease. The Monthly Installment of Rent in effect at any time shall be one-twelfth of the Annual Rent in effect at such time. Rent for any period during the Term which is less than a full month shall be a prorated portion of the Monthly Installment of Rent based upon a thirty (30) day month. Said rent shall be paid to Landlord, without deduction or offset and without notice or demand, at the Landlord’s address, as set forth on the Reference Page, or to such other person or at such other place as Landlord may from time to time designate in writing.

3.2 Tenant recognizes that late payment of any rent or other sum due under this Lease will result in administrative expense to Landlord, the extent of which additional expense is extremely difficult and economically impractical to ascertain. Tenant therefore agrees that if rent or any other sum is not paid when due and payable pursuant to this Lease, a late charge shall be imposed in an amount equal to the greater of: (a) Fifty Dollars ($50.00), or (b) a sum equal to five percent (5%) per month of the unpaid rent or other payment. The amount of the late charge to be paid by Tenant shall be reassessed and added to Tenant’s obligation for each successive monthly period until paid. The provisions of this Section 3.2 in no way relieve Tenant of the obligation to pay rent or other payments on or before the date on which they are due, nor do the terms of this Section 3.2 in any way affect Landlord’s remedies pursuant to Article 19 in the event said rent or other payment is unpaid after date due.

4

Notwithstanding the foregoing, Tenant shall be entitled, not more than once per calendar year, to a notice of non-payment and a five-day grace period thereafter before a late charge may be assessed.

4. RENT ADJUSTMENTS.

4.1 For the purpose of this Article 4, the following terms are defined as follows:

4.1.1 Lease Year: Each calendar year falling partly or wholly within the Term.

4.1.2 Direct Expenses: All direct costs of operation, maintenance, repair and management of the Building (including the amount of any credits which Landlord may grant to particular tenants of the Building in lieu of providing any standard services or paying any standard costs described in this Section 4.1.2 for similar tenants), as determined in accordance with generally accepted accounting principles, including the following costs by way of illustration, but not limitation: water and sewer charges; insurance charges of or relating to all insurance policies and endorsements deemed by Landlord to be reasonably necessary or desirable and relating in any manner to the protection, preservation, or operation of the Building or any part thereof; utility costs, including, but not limited to, the cost of heat, light, power, steam, gas, and waste disposal; the cost of janitorial services; the cost of security and alarm services (including any central station signaling system); window cleaning costs; labor costs; costs and expenses of managing the Building including management fees; air conditioning maintenance costs; elevator maintenance fees and supplies; material costs; equipment costs including the cost of maintenance, repair and service agreements and rental and leasing costs; purchase costs of equipment other than capital items; current rental and leasing costs of items which would be amortizable capital items if purchased; tool costs; licenses, permits and inspection fees; wages and salaries; employee benefits and payroll taxes; accounting and legal fees; any sales, use or service taxes incurred in connection therewith. Direct Expenses shall not include depreciation or amortization of the Building or equipment in the Building except as provided herein, loan principal payments, costs of alterations of tenants’ premises, leasing commissions, interest expenses on long-term borrowings, advertising costs or management salaries for executive personnel other than personnel located at the Building. If, during the Term of this Lease, Landlord shall make a capital expenditure, the total cost of which is not properly includable in Direct Expenses for the Lease Year in which it was made, there shall nevertheless be included in such Direct Expenses for the Lease Year in which it was made and in Direct Expenses for each succeeding Lease Year an annual amount which would amortize such cost over the useful life of the expenditure in question. All such costs shall be amortized over the reasonable life of such expenditures in accordance with such reasonable life and amortization schedules as shall be determined by Landlord in accordance with generally accepted accounting principles, with interest on the unamortized amount at one percent (1%) in excess of the prime lending rate announced from time to time as such by The Northern Trust Company of Chicago, Illinois. Without limiting the generality of the foregoing, Landlord shall be entitled to amortize and include as an additional rental adjustment: (i) an allocable portion of the cost of capital improvement items which are reasonably calculated to reduce operating expenses; (ii) fire sprinklers and suppression systems and other life safety systems; and (iii) other capital expenses which are required under any governmental laws, regulations or ordinances which were not applicable to the Building at the time it was constructed. The following items are not included in Direct Expenses:

4.1.2.1 Cost of permits, licenses and inspection fees incurred by Landlord to prepare, renovate, repaint, or redecorate any space leased to any existing tenant or prospective tenant of the Building;

4.1.2.2 Advertising and promotional expenditures incurred to lease space to new tenants or retain existing tenants;

4.1.2.3 Legal fees and expenses incurred by Landlord to resolve disputes with tenants;

4.1.2.4 Cost of replacement of any items covered under warranty;

4.1.2.5 Cost to correct or any penalty or fine incurred by Landlord due to Landlord’s violation of any federal, stated or local law or regulation;

4.1.2.6 The Landlord’s general corporate overhead and administrative expenses;

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4.1.2.7 Any cost to test, survey, cleanup, contain, abate, remove or otherwise remedy hazardous waste or asbestos containing materials unless they are in or on the Premises due to tenant’s negligence or intentional act;

4.1.2.8 Cost of repairs caused by the Landlord’s negligence;

4.1.2.9 Interest or penalties for any late payments by Landlord;

4.1.2.10 Costs (including, without limitation, attorneys’ fees and disbursements) incurred in connection with any judgment, settlement or arbitration award resulting from any tort liability;

4.1.2.11 Compensation paid to any Building employee to the extent that the same is not fairly allocable to the work or service provided by such employee to the Building;

4.1.2.12 Costs of repairs or replacements incurred by reason of fire or other casualty or caused by the exercise of the right of eminent domain, whether or not insurance proceeds or a condemnation award are recovered or adequate for such purposes (however, deductibles are includable in Direct Expenses);

4.1.2.13 Costs of any heating, ventilating, air conditioning, janitorial or other Building services provided to other tenants during other than Building business hours;

4.1.2.14 Rent or other charges payable under any ground or underlying lease;

4.1.2.15 Costs of any item which are reimbursable to Landlord by other tenants or third parties other than through operating costs pass-through provisions in the leases of other tenants in the Building (if any);

4.1.2.16 Except for normal office equipment and short-term rentals of machines or equipment, lease payments for rented equipment, the cost of which equipment would constitute a capital expenditure if the equipment were to have been purchased (except to the extent that amortization of any such capital expenditure would be permitted as a Direct Expense pursuant to the Lease);

4.1.2.17 The cost of furnishing and installing replacement light bulbs and ballasts in any tenant areas of the Building, excluding the Premises;

4.1.2.18 An amount equal to all amounts received by Landlord through proceeds of insurance to the extent the proceeds are compensation for expenses which (i) previously were included in operating costs hereunder, (ii) are included in operating costs for the comparative year in which the insurance proceeds are received or (iii) will be included as operating costs in a subsequent comparative year;

4.1.2.19 Costs and expenses of governmental licenses and permits, or renewals thereof, unless the same are for governmental licenses or permits normal to the operation or maintenance of the building project;

4.1.2.20 Costs of any work or service performed for any facility or property other than the Building;

4.1.2.21 Any expenses related exclusively to any retail or storage space in, on or about the Building or appurtenant or adjacent thereto; and

4.1.2.22 Costs of electrical energy furnished directly to any Premises of other tenants, or to other rentable areas, of the Building, other than costs of electrical energy for the Building’s HVAC system.

All Direct Expenses shall be entirely net of rebates, credits and similar items of which Landlord receives the benefit.”

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4.1.3 Taxes: Real estate taxes and any other taxes, charges and assessments which are levied with respect to the Building or the land appurtenant to the Building, or with respect to any improvements, fixtures and equipment or other property of Landlord, real or personal, located in the Building and used in connection with the operation of the Building and said land, any payments to any ground lessor in reimbursement of tax payments made by such lessor; and all fees, expenses and costs incurred by Landlord in investigating, protesting, contesting or in any way seeking to reduce or avoid increase in any assessments, levies or the tax rate pertaining to any Taxes to be paid by Landlord in any Lease Year. Taxes shall not include any corporate franchise, or estate, inheritance or net income tax, or tax imposed upon any transfer by Landlord of its interest in this Lease or the Building.

4.2 Tenant shall pay as additional rent for each Lease Year Tenant’s Proportionate Share of Direct Expenses and Taxes incurred for such Lease Year.

4.3 The annual determination of Direct Expenses shall be made by Landlord and, if certified by a nationally recognized firm of public accountants selected by Landlord, shall be binding upon Landlord and Tenant. Tenant may review the books and records supporting such determination in the office of Landlord, or Landlord’s agent, during normal business hours, upon giving Landlord five (5) days advance written notice within sixty (60) days after receipt of such determination, but in no event more often than once in any one year period. In the event that during all or any portion of any Lease Year, the Building is not fully rented and occupied Landlord may make any appropriate adjustment in occupancy-related Direct Expenses for such year for the purpose of avoiding distortion of the amount of such Direct Expenses to be attributed to Tenant by reason of variation in total occupancy of the Building, by employing sound accounting and management principles to determine Direct Expenses that would have been paid or incurred by Landlord had the Building been fully rented and occupied, and the amount so determined shall be deemed to have been Direct Expenses for such Lease Year.

4.4 Prior to the actual determination thereof for a Lease Year, Landlord may from time to time reasonably estimate, using the prior year’s costs and expenses as a guide, Tenant’s liability for Direct Expenses and/or Taxes under Section 4.2, Article 6 and Article 29 for the Lease Year or portion thereof. Landlord will give Tenant written notification of the amount of such estimate and Tenant agrees that it will pay, by increase of its Monthly Installments of Rent due in such Lease Year, additional rent in the amount of such estimate. Any such increased rate of Monthly Installments of Rent pursuant to this Section 4.4 shall remain in effect until further written notification to Tenant pursuant hereto.

4.5 When the above mentioned actual determination of Tenant’s liability for Direct Expenses and/or Taxes is made for any Lease Year and when Tenant is so notified in writing, then:

4.5.1 If the total additional rent Tenant actually paid pursuant to Section 4.3 on account of Direct Expenses and/or Taxes for the Lease Year is less than Tenant’s liability for Direct Expenses and/or Taxes, then Tenant shall pay such deficiency to Landlord as additional rent in one lump sum within thirty (30) days of receipt of Landlord’s bill therefor; and

4.5.2 If the total additional rent Tenant actually paid pursuant to Section 4.3 on account of Direct Expenses and/or Taxes for the Lease Year is more than Tenant’s liability for Direct Expenses and/or Taxes, then Landlord shall credit the difference against the then next due payments to be made by Tenant under this Article 4.

4.6 If the Commencement Date is other than January 1 or if the Termination Date is other than December 31, Tenant’s liability for Direct Expenses (estimated or otherwise) and Taxes for the Lease Year in which said Date occurs shall be prorated based upon a three hundred sixty-five (365) day year.

5. SECURITY DEPOSIT.

5.1 Tenant shall deposit the Security Deposit with Landlord upon the execution of this Lease. Said sum shall be held by Landlord as security for the faithful performance by Tenant of all the terms, covenants and conditions of this Lease to be kept and performed by Tenant and not as an advance rental deposit or as a measure of

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Landlord’s damage in case of Tenant’s default. If an Event of Default occurs with respect to any provision of this Lease, Landlord may use any part of the Security Deposit for the payment of any rent or any other sum in default, or for the payment of any amount which Landlord may spend or become obligated to spend by reason of Tenant’s default, or to compensate Landlord for any other loss or damage which Landlord may suffer by reason of Tenant’s default. If any portion is so used, Tenant shall within five (5) days after written demand therefor, deposit with Landlord an amount sufficient to restore the Security Deposit to its original amount and Tenant’s failure to do so shall be a material breach of this Lease unless Tenant provides a good faith basis to dispute the charge to be applied against the Security Deposit, but this right to dispute shall not apply where the Security Deposit is applied against unpaid amounts of the Monthly Installment of Rent. Except to such extent, if any, as shall be required by law, Landlord shall not be required to keep the Security Deposit separate from its general funds, and Tenant shall not be entitled to interest on such deposit. If Tenant shall fully and faithfully perform every provision of this Lease to be performed by it, the Security Deposit or any balance thereof shall be returned to Tenant at such time within thirty (30) days after termination of this Lease when Landlord shall have determined that all of Tenant’s obligations under this Lease have been fulfilled.

5.2 The Security Deposit provided for above shall be in the form of a letter of credit consistent with the terms of this paragraph 5.2. Simultaneously with the execution and delivery of this Lease, Tenant shall deliver to Landlord an Irrevocable Standby Letter of Credit (the “letter of credit”) in the amount of $171,154.50 (eleven months of rent) and in favor of Landlord as beneficiary. Upon occurrence of an Event of Default under this Lease, Landlord, in addition to all other rights and remedies provided under the Lease, shall have the right draw down the full balance of the letter of credit, retain the proceeds and/or apply said proceeds as provided in said paragraph 5.1. The following terms and conditions shall govern the letter of credit:

5.2.1 Provided that Tenant is not then in default, the amount of the letter of credit may be reduced (or a replacement letter of credit may be issued in such lesser amount) as follows:

5.2.1.1 The letter of credit amount may be reduced to $93,357 (six months of rent) when Tenant has achieved $10,000,000 in revenue and a 10% net operating margin, and has sustained same for a twelve (12) consecutive month period.

5.2.1.2 The letter of credit amount may be reduced to $46,678.50 (three months of rent) when Tenant has achieved $50,000,000 in revenue and a 10% net operating margin, and has sustained same for a twelve (12) consecutive month period.

5.2.1.3 If Tenant requests a reduction in the letter of credit amount per the foregoing, it must present audited financial statements confirming that the above requirements have been satisfied.

5.2.2 The letter of credit shall be in favor of Landlord, shall be issued by a commercial bank reasonably acceptable to Landlord having a Standard & Poors rating of “A” or better, shall comply with all of the terms and conditions of this paragraph 5.2 and shall otherwise be in form reasonably acceptable to Landlord. The initial letter of credit shall have an expiration date not earlier than eighteen (18) months after the Commencement Date.

5.2.3 The letter of credit or any replacement letter of credit shall be irrevocable for the term thereof and shall automatically renew on a year to year basis until a period ending not earlier than three (3) months after the Termination Date (“End Date”) without any action whatsoever on the part of Landlord; provided that the issuing bank shall have the right not to renew the letter of credit by giving written notice to Landlord not less than sixty (60) days prior to the expiration of the then current term of the letter of credit that it does not intend to renew the letter of credit. Tenant understands that the election by the issuing bank not to renew the letter of credit shall not, in any event, diminish the obligation of Tenant to maintain such an irrevocable letter of credit in favor of Landlord through such date.

5.2.4 Landlord, or its then managing agent, shall have the right from time to time to make one or more draws on the letter of credit at any time that an Event of Default has occurred. Funds may be drawn

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down on the letter of credit upon presentation to the issuing bank of Landlord’s (or Landlord’s then managing agent’s) certificate stating as follows:

“The Landlord is entitled to draw on this Credit pursuant to that certain Lease dated for reference August 20, 2001, between TMT 290 INDUSTRIAL PARK, INC., Landlord, and ASPEN AEROGELS, INC.., Tenant, as amended from time to time.”

5.2.5 It is understood that if Landlord or its managing agent be a corporation, partnership or other entity, then such statement shall be signed by an officer (if a corporation), a general partner (if a partnership), or any authorized party (if another entity). Tenant acknowledges and agrees (and the letter of credit shall so state) that the letter of credit shall be honored by the issuing bank without inquiry as to the truth of the statements set forth in such draw request and regardless of whether the Tenant disputes the content of such statement.

5.2.6 In the event of a transfer of Landlord’s interest in the Premises, Landlord shall have the right to transfer the letter of credit to the transferee and thereupon the Landlord shall, without any further agreement between the parties, be released by Tenant from all liability therefor, and it is agreed that the provisions hereof shall apply to every transfer or assignment of said letter of credit to a new landlord. The letter of credit must specifically provide that it is transferable by Landlord.

5.2.7 Without limiting the generality of the foregoing, if the letter of credit expires earlier than the End Date, or the issuing bank notifies Landlord that it shall not renew the letter of credit, Landlord shall accept a renewal thereof or substitute letter credit (such renewal of substitute letter of credit to be in effect not later than thirty (30) days prior to the expiration thereof), irrevocable and automatically renewable as above provided to the End Date upon the same terms as the expiring letter of credit or upon such other terms as may be acceptable to Landlord. However, if (i) the letter of credit is not timely renewed, or (ii) a substitute letter of credit, complying with all of the terms and conditions of this paragraph 5.2 is not timely received, Landlord may present such letter of credit to the issuing bank, and the entire sum so obtained shall be paid to Landlord, to be held by Landlord until Tenant would otherwise be entitled to the return of the letter of credit, and to be retained by as a Security Deposit under paragraph 5.1. So long as no Event of Default occurs, the amount so retained by Landlord will be reduced as set forth in paragraph 5.2.1 above, with the final balance to be released when Tenant is entitled to the return of its Security Deposit.

5.2.8 The letter of credit form attached hereto as Exhibit E is hereby approved.

6. ALTERATIONS.

6.1 Except for those, if any, specifically provided for in Exhibit B to this Lease, Tenant shall not make or suffer to be made any alterations, additions, or improvements, including, but not limited to, the attachment of any fixtures or equipment in, on, or to the Premises or any part thereof or the making of any improvements as required by Article 7, without the prior written consent of Landlord. When applying for such consent, Tenant shall, if requested by Landlord, furnish complete plans and specifications for such alterations, additions and improvements. Landlord’s consent shall not be required (but notice to Landlord shall be required) with respect to de minimus alterations which (i) are not structural in nature, (ii) are not visible from the exterior of the Building, (iii) do not affect or require modification of the Building’s electrical, mechanical, plumbing, HVAC or other systems, and (iv) do not cost more than $10,000 in aggregate in any calendar year.

6.2 Except for those alterations listed on Exhibit B, in the event Landlord consents to the making of any such alteration, addition or improvement by Tenant, the same shall be made using a licensed contractor reasonably approved by Landlord at Tenant’s sole cost and expense. If Tenant shall employ any Contractor and such Contractor or any Subcontractor of such Contractor shall employ any non-union labor or supplier, Tenant shall be responsible for any and all delays, damages and extra costs suffered by Landlord as a result of any dispute with any labor unions concerning the wage, hours, terms or conditions of the employment of any such labor. In any event Landlord may charge Tenant a reasonable charge to cover its direct out-of-pocket overhead as it relates to such proposed work.

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6.3 All alterations, additions or improvements proposed by Tenant shall be constructed in accordance with all government laws, ordinances, rules and regulations and Tenant shall, prior to construction, provide the additional insurance required under Article 11 in such case, and also all such assurances to Landlord, including but not limited to, waivers of lien, surety company performance bonds and personal guaranties of individuals of substance as Landlord shall reasonably require to assure payment of the costs thereof and to protect Landlord and the Building and appurtenant land against any loss from any mechanic’s, materialmen’s or other liens. Tenant shall pay in addition to any sums due pursuant to Article 4, any increase in real estate taxes attributable to any such alteration, addition or improvement for so long, during the Term, as such increase is ascertainable; at Landlord’s election said sums shall be paid in the same way as sums due under Article 4.

6.4 All alterations, additions, and improvements, except any manufacturing equipment, whether attached to the Premises or not, in, on, or to the Premises made or installed by Tenant, including carpeting, shall be and remain the property of Tenant during the Term but, excepting furniture, furnishings, movable partitions of less than full height from floor to ceiling and other trade fixtures, shall become a part of the realty and belong to Landlord without compensation to Tenant upon the expiration or sooner termination of the Term, at which time title shall pass to Landlord under this Lease as by a bill of sale, unless Landlord elects otherwise. Upon such election by Landlord, Tenant shall upon demand by Landlord, at Tenant’s sole cost and expense, forthwith and with all due diligence remove any such alterations, additions or improvements which are designated by Landlord to be removed, and Tenant shall forthwith and with all due diligence, at its sole cost and expense, repair and restore the Premises to their original condition, reasonable wear and tear and damage by fire or other casualty excepted.

7. REPAIR.

7.1 Landlord shall have no obligation to alter, remodel, improve, repair, decorate or paint the Premises, except as specified in Exhibit B if attached to this Lease and except that Landlord shall repair and maintain the structural portions of the roof, walls and foundation of the Building. By taking possession of the Premises, Tenant accepts them as being in good order, condition and repair and in the condition in which Landlord is obligated to deliver them. It is hereby understood and agreed that no representations respecting the condition of the Premises or the Building have been made by Landlord to Tenant, except as specifically set forth in this Lease. Landlord shall not be liable for any failure to make any repairs or to perform any maintenance unless such failure shall persist for an unreasonable time after written notice of the need of such repairs or maintenance is given to Landlord by Tenant. Landlord shall also be obligated to provide the following services: (1) to plow snow and treat ice on sidewalks, roadways and loading areas, (2) to maintain and clean all outdoor facilities including, without limitation, to maintain all lawns, landscaping, and repave and restripe the parking lot when reasonably necessary and to install, maintain or replace when necessary the outdoor lighting systems for the parking areas, (3) to maintain common area lights in good working order and condition, (4) to cause the boiler system providing baseboard heat to the Premises and the Building to be cleaned and maintained regularly, and (5) to maintain and repair the Building as necessary to apply with all applicable government requirements, including without limitation the make-up air system. The cost of performance of Landlord’s obligations under this paragraph is included in Direct Expenses as provided in Paragraph 4.1.2.

7.2 Tenant shall at its own cost and expense keep and maintain all parts of the Premises and such portion of the Building and improvements as are within the exclusive control of Tenant in good condition, promptly making all necessary repairs and replacements, whether ordinary or extraordinary, with materials and workmanship of the same character, kind and quality as the original (including, but not limited to, repair and replacement of all fixtures installed by Tenant, water heaters serving the Premises, windows, glass and plate glass, doors, skylights, any special office entries, interior walls and finish work, floors and floor coverings, heating and air conditioning systems serving the Premises, electrical systems and fixtures, sprinkler systems, dock boards, truck doors, dock bumpers, plumbing work and fixtures, and performance of regular removal of trash and debris). Tenant as part of its obligations hereunder shall keep the Premises in a clean and sanitary condition. Tenant will, as far as possible keep all such parts of the Premises from deterioration due to ordinary wear and from falling temporarily out of repair, and upon termination of this Lease in any way Tenant will yield up the Premises to Landlord in good condition and repair, loss by fire or other casualty excepted (but not excepting any damage to glass). Tenant shall, at its own cost and expense, repair any damage to the Premises or the Building resulting from and/or caused in whole or in part by the negligence or misconduct of Tenant, its agents, employees, invitees, or any other person entering upon the Premises as a result of Tenant’s business activities or caused by Tenant’s default hereunder.

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7.3 Except as provided in Article 22, there shall be no abatement of rent and no liability of Landlord by reason of any injury to or interference with Tenant’s business arising from the making of any repairs, alterations or improvements in or to any portion of the Building or the Premises or to fixtures, appurtenances and equipment in the Building. Except to the extent, if any, prohibited by law, Tenant waives the right to make repairs at Landlord’s expense under any law, statute or ordinance now or hereafter in effect.

7.4 Tenant shall, at its own cost and expense, enter into a regularly scheduled preventive maintenance/service contract with a maintenance contractor reasonably approved by Landlord for servicing all heating and air conditioning systems and equipment exclusively serving the Premises (and a copy thereof shall be furnished to Landlord). The service contract must include all services suggested by the equipment manufacturer in the operation/maintenance manual and must become effective within thirty (30) days of the date Tenant takes possession of the Premises. Landlord may, upon notice to Tenant, enter into such a maintenance/ service contract on behalf of Tenant or perform the work and in either case, charge Tenant the cost thereof along with a reasonable amount for Landlord’s overhead.

7.5 If by reason of the failure of Landlord to furnish electrical, plumbing, HVAC or water service (“Critical Services”) required to be provided by Landlord and without fault of Tenant, whether such failure is excused by reason of force majeure or constitutes an unexcused default, and if Tenant’s ability to conduct business at the Premises is materially and adversely affected for five (5) consecutive days or more and notice thereof has been given to Landlord (and whether or not Tenant elects to exercise its rights of self-help) Tenant shall have the right to a full abatement of Rent, Direct Expenses and other charges payable by Tenant hereunder retroactively from the date Critical Services (or any of them) have ceased until such time as such Critical Service(s) have been restored. If Critical Service(s) can not be restored and Tenant’s ability to conduct business at the Premises has been materially and adversely affected for a period of one hundred twenty (120) days after notice thereof to Landlord, Tenant may terminate this Lease upon no less than fifteen (15) days notice to Landlord unless such Critical Services are restored during said 15 day period.

7.6 If necessary by reason of an emergency, or by reason of an imminent threat of injury to persons or damage to property, Tenant may cure a failure by Landlord to perform its obligations under Paragraph 7.1, at the expense and for the account of Landlord, but only after oral or written notice and such opportunity as is reasonable under the circumstances to cause the cure thereof by Landlord.

8. LIENS. Tenant shall keep the Premises, the Building and appurtenant land and Tenant’s leasehold interest in the Premises free from any liens arising out of any services, work or materials performed, furnished, or contracted for by Tenant, or obligations incurred by Tenant. In the event that Tenant shall not, within ten (10) days following the imposition of any such lien, either cause the same to be released of record or provide Landlord with insurance against the same issued by a major title insurance company or such other protection against the same as Landlord shall accept, Landlord shall have the right to cause the same to be released by such means as it shall deem proper, including payment of the claim giving rise to such lien. All such sums paid by Landlord and all expenses incurred by it in connection therewith shall be considered additional rent and shall be payable to it by Tenant on demand.

9. ASSIGNMENT AND SUBLETTING.

9.1 Tenant shall not have the right to assign or pledge this Lease or to sublet the whole or any part of the Premises whether voluntarily or by operation of law, or permit the use or occupancy of the Premises by anyone other than Tenant, and shall not make, suffer or permit such assignment, subleasing or occupancy, without the prior written consent of Landlord, such consent not to be unreasonably withheld, and said restrictions shall be binding upon any and all assignees of the Lease and subtenants of the Premises. In the event Tenant desires to sublet, or permit such occupancy of, the Premises, or any portion thereof, or assign this Lease, Tenant shall give written notice thereof to Landlord at least thirty (30) days but no more than one hundred eighty (180) days prior to the proposed commencement date of such subletting or assignment, which notice shall set forth the name of the proposed subtenant or assignee, the relevant terms of any sublease or assignment and copies of financial reports and other relevant financial reports and other relevant financial information of the proposed subtenant or assignee.

9.2 Notwithstanding any assignment or subletting, permitted or otherwise, Tenant shall at all times remain directly, primarily and fully responsible and liable for the payment of the rent specified in this Lease and for

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compliance with all of its other obligations under the terms, provisions and covenants of this Lease. Upon the occurrence of an Event of Default, if the Premises or any part of them are then assigned or sublet, Landlord, in addition to any other remedies provided in this Lease or provided by law, may, at its option, collect directly from such assignee or subtenant all rents due and becoming due to Tenant under such assignment or sublease and apply such rent against any sums due to Landlord from Tenant under this Lease, and no such collection shall be construed to constitute a novation or release of Tenant from the further performance of Tenant’s obligations under this Lease.

9.3 In addition to Landlord’s right to approve of any subtenant or assignee, Landlord shall have the option, in its sole discretion, in the event of any proposed subletting or assignment, to terminate this Lease, or in the case of a proposed subletting of less than the entire Premises, to recapture the portion of the Premises to be sublet, as of the date the subletting or assignment is to be effective. The option shall be exercised, if at all, by Landlord giving Tenant written notice given by Landlord to Tenant within sixty (60) days following Landlord’s receipt of Tenant’s written notice as required above. If this Lease shall be terminated with respect to the entire Premises pursuant to this Section, the Term of this Lease shall end on the date stated in Tenant’s notice as the effective date of the sublease or assignment as if that date had been originally fixed in this Lease for the expiration of the Term. If Landlord recaptures under this Section only a portion of the Premises, the rent to be paid from time to time during the unexpired Term shall abate proportionately based on the proportion by which the approximate square footage of the remaining portion of the Premises shall be less than that of the Premises as of the date immediately prior to such recapture. Tenant shall, at Tenant’s own cost and expense, discharge in full any outstanding commission obligation on the part of Landlord with respect to this Lease, and any commissions which may be due and owing as a result of any proposed assignment or subletting, whether or not the Premises are recaptured pursuant to this Section 9.3 and rented by Landlord to the proposed tenant or any other tenant.

9.4 In the event that Tenant sells, sublets, assigns or transfers this Lease, Tenant shall pay to Landlord as additional rent an amount equal to seventy-five percent (75%) of any Increased Rent (as defined below) when and as such Increased Rent is received by Tenant, but after Tenant has first recovered, out of 100% of increased rent, its reasonable attorneys’ fees, leasing commissions and tenant improvement costs incurred in connection with such transfer. As used in this Section, “Increased Rent” shall mean the excess of (i) all rent and other consideration which Tenant is entitled to receive by reason of any sale, sublease, assignment or other transfer of this Lease, over (ii) the rent otherwise payable by Tenant under this Lease at such time. For purposes of the foregoing, any consideration received by Tenant in form other than cash shall be valued at its fair market value as determined by Landlord in good faith.

9.5 Notwithstanding any other provision hereof, Tenant shall have no right to make (and Landlord shall have the absolute right to refuse consent to) any assignment of this Lease or sublease of any portion of the Premises if at the time of either Tenant’s notice of the proposed assignment or sublease or the proposed commencement date thereof, there shall exist any uncured default of Tenant or matter which will become a default of Tenant with passage of time unless cured, or if the proposed assignee or sublessee is an entity: (a) with which Landlord is already in negotiation as evidenced by the issuance of a written proposal; (b) is already an occupant of the Building unless Landlord is unable to provide the amount of space required by such occupant; (c) is a governmental agency; (d) is incompatible with the character of occupancy of the Building; or (e) would subject the Premises to a use which would: (i) involve increased personnel or wear upon the Building; (ii) violate any exclusive right granted to another tenant of the Building; (iii) require any addition to or modification of the Premises or the Building in order to comply with building code or other governmental requirements; or, (iv) involve a violation of Section 1.2. Tenant expressly agrees that Landlord shall have the absolute right to refuse consent to any such assignment or sublease and that for the purposes of any statutory or other requirement of reasonableness on the part of Landlord such refusal shall be reasonable.

9.6 Upon any request to assign or sublet, Tenant will pay to Landlord the Assignment/Subletting Fee plus, on demand, a sum equal to all of Landlord’s reasonable costs, including reasonable attorney’s fees, incurred in investigating and considering any proposed or purported assignment or pledge of this Lease or sublease of any of the Premises, regardless of whether Landlord shall consent to, refuse consent, or determine that Landlord’s consent is not required for, such assignment, pledge or sublease. Any purported sale, assignment, mortgage, transfer of this Lease or subletting which does not comply with the provisions of this Article 9 shall be void.

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9.7 If Tenant is a corporation, partnership or trust, any transfer or transfers of or change or changes within any twelve month period in the number of the outstanding voting shares of the corporation, the general partnership interests in the partnership or the identity of the persons or entities controlling the activities of such partnership or trust resulting in the persons or entities owning or controlling a majority of such shares, partnership interests or activities of such partnership or trust at the beginning of such period no longer having such ownership or control shall be regarded as equivalent to an assignment of this Lease to the persons or entities acquiring such ownership or control and shall be subject to all the provisions of this Article 9 to the same extent and for all intents and purposes as though such an assignment.

9.8 Notwithstanding the foregoing provisions of this Article to the contrary, Tenant shall be permitted to assign this Lease, or sublet all or a portion of the Premises, to an Affiliate of Tenant without the prior consent of Landlord, if all of the following conditions are first satisfied:

9.8.1 Tenant shall not then be in default under this Lease;

9.8.2 a fully executed copy of such assignment or sublease, the assumption of this Lease by the assignee or acceptance of the sublease by the sublessee, and such other information regarding the assignment or sublease as Landlord may reasonably request, shall have been delivered to Landlord;

9.8.3 the Premises shall continue to be operated solely for the use specified in the Reference Page or other use acceptable to Landlord in its sole discretion;

9.8.4 any guarantor of this Lease reaffirms that its Guaranty remains in full force and effect; and

9.8.5 Tenant shall pay all costs reasonably incurred by Landlord in connection with such assignment or subletting, including without limitation attorneys’ fees.

Tenant acknowledges (and, at Landlord’s request, at the time of such assignment or subletting shall confirm) that in each instance Tenant shall remain liable for performance of the terms and conditions of the Lease despite such assignment or subletting. As used herein the term “Affiliate” shall mean an entity which (i) directly or indirectly controls Tenant or (ii) is under the direct or indirect control of Tenant or (iii) is under common direct or indirect control with Tenant, (iv) is the successor in interest to Tenant by way of merger or consolidation, or by sale of all of the stock of Tenant or of all of the assets of Tenant, so long as the net worth of the surviving or successor entity following such transaction is at least as much as the net worth of Tenant immediately preceding the transaction or at the Commencement Date, whichever is higher. Control shall mean ownership of fifty-one percent (51%) or more of the voting securities or rights of the controlled entity.

10. INDEMNIFICATION. None of the Landlord Entities shall be liable and Tenant hereby waives all claims against them for any damage to any property or any injury to any person in or about the Premises or the Building by or from any cause whatsoever (including without limiting the foregoing, rain or water leakage of any character from the roof, windows, walls, basement, pipes, plumbing works or appliances, the Building not being in good condition or repair, gas, fire, oil, electricity or theft), except that Landlord shall indemnify and hold Tenant harmless from and against any such claims to the extent caused by or arising from the gross negligence or willful misconduct of Landlord or its agents, employees or contractors. Tenant shall protect, indemnify and hold the Landlord Entities harmless from and against any and all loss, claims, liability or costs (including court costs and attorney’s fees) incurred by reason of (a) any damage to any property (including but not limited to property of any Landlord Entity) or any injury (including but not limited to death) to any person occurring in, on or about the Premises or the Building to the extent that such injury or damage shall be caused by or arise from any actual or alleged act, neglect, fault, or omission by or of Tenant, its agents, servants, employees, invitees, or visitors to meet any standards imposed by any duty with respect to the injury or damage; (b) the conduct or management of any work or thing whatsoever done by the Tenant in or about the Premises or from transactions of the Tenant concerning the Premises; (c) Tenant’s failure to comply with any and all governmental laws, ordinances and regulations applicable to the condition or use of the Premises or its occupancy; or (d) any breach or default on the part of Tenant in the performance of any covenant or agreement on the part of the Tenant to be performed pursuant to this Lease. The provisions of this Article shall survive the termination of this Lease with respect to any claims or liability accruing prior to such termination.

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11. INSURANCE.

11.1 Tenant shall keep in force throughout the Term: (a) a Commercial General Liability insurance policy or policies to protect the Landlord Entities against any liability to the public or to any invitee of Tenant or a Landlord Entity incidental to the use of or resulting from any accident occurring in or upon the Premises with a limit of not less than $1,000,000.00 per occurrence and not less than $2,000,000.00 in the annual aggregate, or such larger amount as Landlord may prudently require from time to time, covering bodily injury and property damage liability and $1,000,000 products/completed operations aggregate; (b) Business Auto Liability covering owned, non-owned and hired vehicles with a limit of not less than $1,000,000 per accident; (c) insurance protecting against liability under Worker’s Compensation Laws with limits at least as required by statute; (d) Employers Liability with limits of $500,000 each accident, $500,000 disease policy limit, $500,000 disease—each employee; (e) All Risk or Special Form coverage protecting Tenant against loss of or damage to Tenant’s alterations, additions, improvements, carpeting, floor coverings, panelings, decorations, fixtures, inventory and other business personal property situated in or about the Premises to the full replacement value of the property so insured; and, (f) Business Interruption Insurance with limit of liability representing loss of at least approximately six months of income.

11.2 Each of the aforesaid policies shall (a) be provided at Tenant’s expense; (b) name the Landlord and building management company, if any, as additional insureds; (c) be issued by an insurance company with a minimum Best’s rating of “A:VII” during the Term; and (d) provide that said insurance shall not be canceled unless thirty (30) days prior written notice (ten days for non-payment of premium) shall have been given to Landlord; and said policy or policies or certificates thereof shall be delivered to Landlord by Tenant upon the Commencement Date and at least thirty (30) days prior to each renewal of said insurance.

11.3 Whenever Tenant shall undertake any alterations, additions or improvements in, to or about the Premises (“Work”) the aforesaid insurance protection must extend to and include injuries to persons and damage to property arising in connection with such Work, without limitation including liability under any applicable structural work act, and such other insurance as Landlord shall require; and the policies of or certificates evidencing such insurance must be delivered to Landlord prior to the commencement of any such Work.

12. WAIVER OF SUBROGATION. So long as their respective insurers so permit, Tenant and Landlord hereby mutually waive their respective rights of recovery against each other for any loss insured by fire, extended coverage, All Risks or other insurance now or hereafter existing for the benefit of the respective party but only to the extent of the net insurance proceeds payable under such policies. Each party shall obtain any special endorsements required by their insurer to evidence compliance with the aforementioned waiver.

13. SERVICES AND UTILITIES. Tenant shall pay for all water, gas, heat, light, power, telephone, sewer, sprinkler system charges and other utilities and services used on or from the premises, together with any taxes, penalties, and surcharges or the like pertaining thereto and any maintenance charges for utilities. Tenant shall furnish all electric light bulbs, tubes and ballasts, battery packs for emergency lighting and fire extinguishers for the Premises. If any such services are not separately metered to Tenant, Tenant shall pay such proportion of all charges jointly metered with other premises as determined by Landlord, in its sole discretion, to be reasonable. Any such charges paid by Landlord and assessed against Tenant shall be immediately payable to Landlord on demand and shall be additional rent hereunder. Landlord shall in no event be liable for any interruption or failure of utility services on or to the Premises. Landlord represents that 1,000 amp electrical service is available to the Premises.

14. HOLDING OVER. Tenant shall pay Landlord for each day Tenant retains possession of the Premises or part of them after termination of this Lease by lapse of time or otherwise at the rate (“Holdover Rate”) which shall be 150% of the greater of: (a) the amount of the Annual Rent for the last period prior to the date of such termination plus all Rent Adjustments under Article 4; and, (b) the then market rental value of the Premises as determined by Landlord assuming a new lease of the Premises of the then usual duration and other terms, in either case prorated on a daily basis, and also pay all damages sustained by Landlord by reason of such retention. If Landlord gives notice to Tenant of Landlord’s election to that effect, such holding over shall constitute renewal of this Lease for a period from month to month or one year, whichever shall be specified in such notice, in either case at the Holdover Rate,

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but if the Landlord does not so elect, no such renewal shall result notwithstanding acceptance by Landlord of any sums due hereunder after such termination; and instead, a tenancy at sufferance at the Holdover Rate shall be deemed to have been created. In any event, no provision of this Article 14 shall be deemed to waive Landlord’s right of reentry or any other right under this Lease or at law.

15. SUBORDINATION. Without the necessity of any additional document being executed by Tenant for the purpose of effecting a subordination, this Lease shall be subject and subordinate at all times to ground or underlying leases and to the lien of any mortgages or deeds of trust now or hereafter placed on, against or affecting the Building, Landlord’s interest or estate in the Building, or any ground or underlying lease; provided, however, that if the lessor, mortgagee, trustee, or holder of any such mortgage or deed of trust elects to have Tenant’s interest in this Lease be superior to any such instrument, then, by notice to Tenant, this Lease shall be deemed superior, whether this Lease was executed before or after said instrument. Notwithstanding the foregoing, Tenant covenants and agrees to execute and deliver upon demand such further instruments evidencing such subordination or superiority of this Lease as may be required by Landlord. Tenant’s subordination to any future mortgage may be conditioned upon Tenant’s receipt of a commercially reasonable nondisturbance agreement.

16. RULES AND REGULATIONS. Tenant shall faithfully observe and comply with all the rules and regulations as set forth in Exhibit C to this Lease and all reasonable modifications of and additions to them from time to time put into effect by Landlord. Landlord shall not be responsible to Tenant for the non-performance by any other tenant or occupant of the Building of any such rules and regulations.

17. REENTRY BY LANDLORD.

17.1 Landlord reserves and shall at all times have the right (except in an emergency, on at least 48 hours prior notice and during normal business hours) to re-enter the Premises to inspect the same, to show said Premises to prospective purchasers, mortgagees or, during the last six months of the Term, tenants, and to alter, improve or repair the Premises that is not being utilized by a Tenant and any portion of the Building, without abatement of rent, and may for that purpose erect, use and maintain scaffolding, pipes, conduits and other necessary structures and open any wall, ceiling or floor in and through the Building and Premises where reasonably required by the character of the work to be performed, provided entrance to the Premises shall not be blocked thereby, and further provided that the business of Tenant shall not be interfered with unreasonably.

17.2 Landlord shall have the right at any time to change the arrangement and/or locations of entrances, or passageways, doors and doorways, and corridors, windows, elevators, stairs, toilets or other public parts of the Building and to change the name, number or designation by which the Building is commonly known. However, Landlord shall have no right to alter the entrances to the Premises. In the event that Landlord damages any portion of any wall or wall covering, ceiling, or floor or floor covering within the Premises, Landlord shall repair or replace the damaged portion to match the original as nearly as commercially reasonable but shall not be required to repair or replace more than the portion actually damaged.

17.3 Except to the extent resulting from Landlord’s negligence or willful misconduct, Tenant hereby waives any claim for damages for any injury or inconvenience to or interference with Tenant’s business, any loss of occupancy or quiet enjoyment of the Premises, and any other loss occasioned by any action of Landlord authorized by this Article 17. Tenant agrees to reimburse Landlord, on demand, as additional rent, for any expenses which Landlord may incur in thus effecting compliance with Tenant’s obligations under this Lease.

17.4 For each of the aforesaid purposes, Landlord shall at all times have and retain a key with which to unlock all of the doors in the Premises, excluding Tenant’s vaults and safes or special security areas (designated in advance), and Landlord shall have the right to use any and all means which Landlord may deem proper to open said doors in an emergency to obtain entry to any portion of the Premises. As to any portion to which access cannot be had by means of a key or keys in Landlord’s possession, Landlord is authorized to gain access by such means as Landlord shall elect and the cost of repairing any damage occurring in doing so shall be borne by Tenant and paid to Landlord as additional rent upon demand in the event such entry is warranted by an emergency.

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18. DEFAULT.

18.1 Except as otherwise provided in Article 20, the following events shall be deemed to be Events of Default under this Lease:

18.1.1 Tenant shall fail to pay when due any sum of money becoming due to be paid to Landlord under this Lease, whether such sum be any installment of the rent reserved by this Lease, any other amount treated as additional rent under this Lease, or any other payment or reimbursement to Landlord required by this Lease, whether or not treated as additional rent under this Lease, and such failure shall continue for a period of five days after written notice that such payment was not made when due, but if any such notice shall be given, for the twelve month period commencing with the date of such notice, the failure to pay within five days after due any additional sum of money becoming due to be paid to Landlord under this Lease during such period shall be an Event of Default, without notice.

18.1.2 Tenant shall fail to comply with any term, provision or covenant of this Lease which is not provided for in another Section of this Article and shall not cure such failure within thirty (30) days (forthwith, if the failure involves a hazardous condition) after written notice of such failure to Tenant.

18.1.3 Tenant shall fail to vacate the Premises immediately upon termination of this Lease, by lapse of time or otherwise, or upon termination of Tenant’s right to possession only.

18.1.4 Tenant shall become insolvent, admit in writing its inability to pay its debts generally as they become due, file a petition in bankruptcy or a petition to take advantage of any insolvency statute, make an assignment for the benefit of creditors, make a transfer in fraud of creditors, apply for or consent to the appointment of a receiver of itself or of the whole or any substantial part of its property, or file a petition or answer seeking reorganization or arrangement under the federal bankruptcy laws, as now in effect or hereafter amended, or any other applicable law or statute of the United States or any state thereof.

18.1.5 A court of competent jurisdiction shall enter an order, judgment or decree adjudicating Tenant bankrupt, or appointing a receiver of Tenant, or of the whole or any substantial part of its property, without the consent of Tenant, or approving a petition filed against Tenant seeking reorganization or arrangement of Tenant under the bankruptcy laws of the United States, as now in effect or hereafter amended, or any state thereof, and such order, judgment or decree shall not be vacated or set aside or stayed within thirty (30) days from the date of entry thereof.

19. REMEDIES

19.1 Except as otherwise provided in Article 20, upon the occurrence of any of the Events of Default described or referred to in Article 18, Landlord shall have the option to pursue any one or more of the following remedies without any notice or demand whatsoever, concurrently or consecutively and not alternatively:

19.1.1 Landlord may, at its election, terminate this Lease or terminate Tenant’s right to possession only, without terminating the Lease.

19.1.2 Upon any termination of this Lease, whether by lapse of time or otherwise, or upon any termination of Tenant’s right to possession without termination of the Lease, Tenant shall surrender possession and vacate the Premises immediately, and deliver possession thereof to Landlord, and Tenant hereby grants to Landlord full and free license to enter into and upon the Premises in such event and to repossess Landlord of the Premises as of Landlord’s former estate and to expel or remove Tenant and any others who may be occupying or be within the Premises and to remove Tenant’s signs and other evidence of tenancy and all other property of Tenant therefrom without being deemed in any manner guilty of trespass, eviction or forcible entry or detainer, and without incurring any liability for any damage resulting therefrom, Tenant waiving any right to claim damages for such re-entry and expulsion, and without relinquishing Landlord’s right to rent or any other right given to Landlord under this Lease or by operation of law.

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19.1.3 Upon any termination of this Lease, whether by lapse of time or otherwise, Landlord shall be entitled to recover as damages, all rent, including any amounts treated as additional rent under this Lease, and other sums due and payable by Tenant on the date of termination, plus as liquidated damages and not as a penalty, an amount equal to the sum of: (a) an amount equal to the then present value of the rent reserved in this Lease for the residue of the stated Term of this Lease including any amounts treated as additional rent under this Lease and all other sums provided in this Lease to be paid by Tenant, minus the fair rental value of the Premises for such residue; (b) the value of the time and expense necessary to obtain a replacement tenant or tenants, and the estimated expenses described in Section 19.1.4 relating to recovery of the Premises, preparation for reletting and for reletting itself; and (c) the cost of performing any other covenants which would have otherwise been performed by Tenant. Landlord agrees to use commercially reasonable efforts to mitigate its damages.

19.1.4 Upon any termination of Tenant’s right to possession only without termination of the Lease:

19.1.4.1 Neither such termination of Tenant’s right to possession nor Landlord’s taking and holding possession thereof as provided in Section 19.1.2 shall terminate the Lease or release Tenant, in whole or in part, from any obligation, including Tenant’s obligation to pay the rent, including any amounts treated as additional rent, under this Lease for the full Term, and if Landlord so elects Tenant shall pay forthwith to Landlord the sum equal to the entire amount of the rent, including any amounts treated as additional rent under this Lease, for the remainder of the Term plus any other sums provided in this Lease to be paid by Tenant for the remainder of the Term.

19.1.4.2 Landlord may, but need not, relet the Premises or any part thereof for such rent and upon such terms as Landlord, in its sole discretion, shall determine (including the right to relet the premises for a greater or lesser term than that remaining under this Lease, the right to relet the Premises as a part of a larger area, and the right to change the character or use made of the Premises). In connection with or in preparation for any reletting, Landlord may, but shall not be required to, make repairs, alterations and additions in or to the Premises and redecorate the same to the extent Landlord deems necessary or desirable, and Tenant shall, upon demand, pay the cost thereof, together with Landlord’s expenses of reletting, including, without limitation, any commission incurred by Landlord. If Landlord decides to relet the Premises or a duty to relet is imposed upon Landlord by law, Landlord and Tenant agree that nevertheless Landlord shall at most be required to use only the same efforts Landlord then uses to lease premises in the Building generally and that in any case that Landlord shall not be required to give any preference or priority to the showing or leasing of the Premises over any other space that Landlord may be leasing or have available and may place a suitable prospective tenant in any such other space regardless of when such other space becomes available. Landlord shall not be required to observe any instruction given by Tenant about any reletting or accept any tenant offered by Tenant unless such offered tenant has a creditworthiness acceptable to Landlord and leases the entire Premises upon terms and conditions including a rate of rent (after giving effect to all expenditures by Landlord for tenant improvements, broker’s commissions and other leasing costs) all no less favorable to Landlord than as called for in this Lease, nor shall Landlord be required to make or permit any assignment or sublease for more than the current term or which Landlord would not be required to permit under the provisions of Article 9.

19.1.4.3 Until such time as Landlord shall elect to terminate the Lease and shall thereupon be entitled to recover the amounts specified in such case in Section 19.1.3, Tenant shall pay to Landlord upon demand the full amount of all rent, including any amounts treated as additional rent under this Lease and other sums reserved in this Lease for the remaining Term, together with the costs of repairs, alterations, additions, redecorating and Landlord’s expenses of reletting and the collection of the rent accruing therefrom (including attorney’s fees and broker’s commissions), as the same shall then be due or become due from time to time, less only such consideration as Landlord may have received from any reletting of the Premises; and Tenant agrees that Landlord may file suits from time to time to recover any sums falling due under this Article 19 as they become due. Any proceeds of reletting by Landlord in excess of the amount then owed by Tenant to Landlord from time to time shall be credited against Tenant’s future obligations under this Lease but shall not otherwise be refunded to Tenant or inure to Tenant’s benefit.

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19.2 Landlord may, at Landlord’s option, enter into and upon the Premises if Landlord determines in its sole discretion that Tenant is not acting within a commercially reasonable time to maintain, repair or replace anything for which Tenant is responsible under this Lease and correct the same, without being deemed in any manner guilty of trespass, eviction or forcible entry and detainer and without incurring any liability for any damage or interruption of Tenant’s business resulting therefrom. If Tenant shall have vacated the Premises, Landlord may at Landlord’s option re-enter the Premises at any time during the last six months of the then current Term of this Lease and make any and all such changes, alterations, revisions, additions and tenant and other improvements in or about the Premises as Landlord shall elect, all without any abatement of any of the rent otherwise to be paid by Tenant under this Lease.

19.3 If, on account of any breach or default by Tenant in Tenant’s obligations under the terms and conditions of this Lease, it shall become necessary or appropriate for Landlord to employ or consult with an attorney concerning or to enforce or defend any of Landlord’s rights or remedies arising under this Lease, Tenant agrees to pay all Landlord’s attorney’s fees so incurred which are reasonable and customary. Tenant expressly waives any right to trial by jury.

19.4 Pursuit of any of the foregoing remedies shall not preclude pursuit of any of the other remedies provided in this Lease or any other remedies provided by law (all such remedies being cumulative), nor shall pursuit of any remedy provided in this Lease constitute a forfeiture or waiver of any rent due to Landlord under this Lease or of any damages accruing to Landlord by reason of the violation of any of the terms, provisions and covenants contained in this Lease.

19.5 No act or thing done by Landlord or its agents during the Term shall be deemed a termination of this Lease or an acceptance of the surrender of the Premises, and no agreement to terminate this Lease or accept a surrender of said Premises shall be valid, unless in writing signed by Landlord. No waiver by Landlord of any violation or breach of any of the terms, provisions and covenants contained in this Lease shall be deemed or construed to constitute a waiver of any other violation or breach of any of the terms, provisions and covenants contained in this Lease. Nothing herein shall limit restrict or prevent in any way Tenant from bringing an action against Landlord for constructive eviction or breach of violation of the covenant of quiet enjoyment. Landlord’s acceptance of the payment of rental or other payments after the occurrence of an Event of Default shall not be construed as a waiver of such Default, unless Landlord so notifies Tenant in writing. Forbearance by Landlord in enforcing one or more of the remedies provided in this Lease upon an Event of Default shall not be deemed or construed to constitute a waiver of such Default or of Landlord’s right to enforce any such remedies with respect to such Default or any subsequent Default.

19.6 To secure the payment of all rentals and other sums of money becoming due from Tenant under this Lease, Landlord shall have and Tenant grants to Landlord a first lien upon the leasehold interest of Tenant under this Lease, which lien may be enforced in equity, and a continuing security interest upon all goods, wares, equipment, fixtures, furniture, inventory, accounts, contract rights, chattel paper and other personal property of Tenant situated on the Premises, and such property shall not be removed therefrom without the consent of Landlord until all arrearages in rent as well as any and all other sums of money then due to Landlord under this Lease shall first have been paid and discharged. In the event of a Default under this Lease, Landlord shall have, in addition to any other remedies provided in this Lease or by law, all rights and remedies under the Uniform Commercial Code, including without limitation the right to sell the property described in this Section 19.6 at public or private sale upon five (5) days’ notice to Tenant. Tenant shall execute all such financing statements and other instruments as shall be deemed necessary or desirable in Landlord’s discretion to perfect the security interest hereby created. Notwithstanding the foregoing, Landlord shall subordinate to any traditional third party lender any and all liens and all rights which Landlord now has or may hereinafter require by levy, distraint, security interest or other interest with respect to the items of Tenant’s personal property and assets contained in the Premises, and Landlord will execute any usual and customary documents in connection with such financing memorializing its subordination of a security interest in Tenant’s property, with modifications to such documents as Landlord may reasonably require.

19.7 Any and all property which may be removed from the Premises by Landlord pursuant to the authority of this Lease or of law, to which Tenant is or may be entitled, may be handled, removed and/or stored, as the case may be, by or at the direction of Landlord but at the risk, cost and expense of Tenant, and Landlord shall in no event be responsible for the value, preservation or safekeeping thereof. Tenant shall pay to Landlord, upon

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demand, any and all expenses incurred in such removal and all storage charges against such property so long as the same shall be in Landlord’s possession or under Landlord’s control. Any such property of Tenant not retaken by Tenant from storage within thirty (30) days after removal from the Premises shall, at Landlord’s option, be deemed conveyed by Tenant to Landlord under this Lease as by a bill of sale without further payment or credit by Landlord to Tenant.

20. TENANT’S BANKRUPTCY OR INSOLVENCY.

20.1 If at any time and for so long as Tenant shall be subjected to the provisions of the United States Bankruptcy Code or other law of the United States or any state thereof for the protection of debtors as in effect at such time (each a “Debtor’s Law”):

20.1.1 Tenant, Tenant as debtor-in-possession, and any trustee or receiver of Tenant’s assets (each a “Tenant’s Representative”) shall have no greater right to assume or assign this Lease or any interest in this Lease, or to sublease any of the Premises than accorded to Tenant in Article 9, except to the extent Landlord shall be required to permit such assumption, assignment or sublease by the provisions of such Debtor’s Law. Without limitation of the generality of the foregoing, any right of any Tenant’s Representative to assume or assign this Lease or to sublease any of the Premises shall be subject to the conditions that:

20.1.1.1 Such Debtor’s Law shall provide to Tenant’s Representative a right of assumption of this Lease which Tenant’s Representative shall have timely exercised and Tenant’s Representative shall have fully cured any default of Tenant under this Lease.

20.1.1.2 Tenant’s Representative or the proposed assignee, as the case shall be, shall have deposited with Landlord as security for the timely payment of rent an amount equal to the larger of: (a) three months’ rent and other monetary charges accruing under this Lease; and (b) any sum specified in Article 5; and shall have provided Landlord with adequate other assurance of the future performance of the obligations of the Tenant under this Lease. Without limitation, such assurances shall include, at least, in the case of assumption of this Lease, demonstration to the satisfaction of the Landlord that Tenant’s Representative has and will continue to have sufficient unencumbered assets after the payment of all secured obligations and administrative expenses to assure Landlord that Tenant’s Representative will have sufficient funds to fulfill the obligations of Tenant under this Lease; and, in the case of assignment, submission of current financial statements of the proposed assignee, audited by an independent certified public accountant reasonably acceptable to Landlord and showing a net worth and working capital in amounts determined by Landlord to be sufficient to assure the future performance by such assignee of all of the Tenant’s obligations under this Lease.

20.1.1.3 The assumption or any contemplated assignment of this Lease or subleasing any part of the Premises, as shall be the case, will not breach any provision in any other lease, mortgage, financing agreement or other agreement by which Landlord is bound.

20.1.1.4 Landlord shall have, or would have had absent the Debtor’s Law, no right under Article 9 to refuse consent to the proposed assignment or sublease by reason of the identity or nature of the proposed assignee or sublessee or the proposed use of the Premises concerned.

21. QUIET ENJOYMENT. Landlord represents and warrants that it has full right and authority to enter into this Lease and that Tenant, while paying the rental and performing its other covenants and agreements contained in this Lease, shall peaceably and quietly have, hold and enjoy the Premises and use the parking areas and any common areas for the Term without hindrance or molestation from Landlord subject to the terms and provisions of this Lease. Landlord shall not be liable for any interference or disturbance by other tenants or third persons, nor shall Tenant be released from any of the obligations of this Lease because of such interference or disturbance.

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22. DAMAGE BY FIRE, ETC.

22.1 In the event the Premises or the Building are damaged by fire or other cause and in Landlord’s reasonable estimation such damage can be materially restored within two hundred ten (210) days, Landlord shall forthwith repair the same and this Lease shall remain in full force and effect, except that Tenant shall be entitled to a proportionate abatement in rent from the date of such damage. Such abatement of rent shall be made pro rata in accordance with the extent to which the damage and the making of such repairs shall interfere with the use and occupancy by Tenant of the Premises from time to time. Within thirty (30) days from the date of such damage, Landlord shall notify Tenant, in writing, of Landlord’s reasonable estimation of the length of time within which material restoration can be made, and Landlord’s determination shall be binding on Tenant. For purposes of this Lease, the Building or Premises shall be deemed “materially restored” if they are in such condition as would not prevent or materially interfere with Tenant’s use of the Premises for the purpose for which it was being used immediately before such damage.

22.2 If such repairs cannot, in Landlord’s reasonable estimation, be made within two hundred ten (210) days, Landlord and Tenant shall each have the option of giving the other, at any time within thirty (30) days after such damage, notice terminating this Lease as of the date of such damage. In the event of the giving of such notice, this Lease shall expire and all interest of the Tenant in the Premises shall terminate as of the date of such damage as if such date had been originally fixed in this Lease for the expiration of the Term. In the event that neither Landlord nor Tenant exercises its option to terminate this Lease, then Landlord shall repair or restore such damage, this Lease continuing in full force and effect, and the rent hereunder shall be proportionately abated as provided in Section 22.1.

22.3 Landlord shall not be required to repair or replace any damage or loss by or from fire or other cause to any panelings, decorations, partitions, additions, railings, ceilings, floor coverings, office fixtures or any other property or improvements installed on the Premises or belonging to Tenant. Any insurance which may be carried by Landlord or Tenant against loss or damage to the Building or Premises shall be for the sole benefit of the party carrying such insurance and under its sole control.

22.4 In the event that Landlord should fail to complete such repairs and material restoration within sixty (60) days after the date estimated by Landlord therefor as extended by this Section 22.4, Tenant may at its option and as its sole remedy terminate this Lease by delivering written notice to Landlord, within fifteen (15) days after the expiration of said period of time, whereupon the Lease shall end on the date of such notice or such later date fixed in such notice as if the date of such notice was the date originally fixed in this Lease for the expiration of the Term; provided, however, that if construction is delayed because of changes, deletions or additions in construction requested by Tenant, strikes, lockouts, casualties, Acts of God, war, material or labor shortages, government regulation or control or other causes beyond the reasonable control of Landlord, the period for restoration, repair or rebuilding shall be extended for the amount of time Landlord is so delayed.

22.5 Notwithstanding anything to the contrary contained in this Article: (a) Landlord shall not have any obligation whatsoever to repair, reconstruct, or restore the Premises when the damages resulting from any casualty covered by the provisions of this Article 22 occur during the last twelve (12) months of the Term or any extension thereof, but if Landlord determines not to repair such damages Landlord shall notify Tenant and if such damages shall render any material portion of the Premises untenantable Tenant shall have the right to terminate this Lease by notice to Landlord within fifteen (15) days after receipt of Landlord’s notice; and (b) in the event the holder of any indebtedness secured by a mortgage or deed of trust covering the Premises or Building requires that any insurance proceeds be applied to such indebtedness, then Landlord shall have the right to terminate this Lease by delivering written notice of termination to Tenant within fifteen (15) days after such requirement is made by any such holder, whereupon this Lease shall end on the date of such damage as if the date of such damage were the date originally fixed in this Lease for the expiration of the Term.

22.6 In the event of any damage or destruction to the Building or Premises by any peril covered by the provisions of this Article 22, it shall be Tenant’s responsibility to properly secure the Premises and upon notice from Landlord to remove forthwith, at its sole cost and expense, such portion of all of the property belonging to Tenant or its licensees from such portion or all of the Building or Premises as Landlord shall request.

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23. EMINENT DOMAIN. If all or any substantial part of the Premises shall be taken or appropriated by any public or quasi-public authority under the power of eminent domain, or conveyance in lieu of such appropriation, either party to this Lease shall have the right, at its option, of giving the other, at any time within thirty (30) days after such taking, notice terminating this Lease, except that Tenant may only terminate this Lease by reason of taking or appropriation, if such taking or appropriation (including a taking or appropriation of parking) shall be so substantial as to materially interfere with Tenant’s use and occupancy of the Premises, in Tenant’s reasonable judgment. If neither party to this Lease shall so elect to terminate this Lease, the rental thereafter to be paid shall be adjusted on a fair and equitable basis under the circumstances. In addition to the rights of Landlord above, if any substantial part of the Building shall be taken or appropriated by any public or quasi-public authority under the power of eminent domain or conveyance in lieu thereof, and regardless of whether the Premises or any part thereof are so taken or appropriated, Landlord shall have the right, at its sole option, to terminate this Lease. Landlord shall be entitled to any and all income, rent, award, or any interest whatsoever in or upon any such sum, which may be paid or made in connection with any such public or quasi-public use or purpose, and Tenant hereby assigns to Landlord any interest it may have in or claim to all or any part of such sums, other than any separate award which may be made with respect to Tenant’s trade fixtures and moving expenses; Tenant shall make no claim for the value of any unexpired Term.

24. SALE BY LANDLORD. In event of a sale or conveyance by Landlord of the Building, the same shall operate to release Landlord from any future liability upon any of the covenants or conditions, expressed or implied, contained in this Lease in favor of Tenant, and in such event Tenant agrees to look solely to the responsibility of the successor in interest of Landlord in and to this Lease. Except as set forth in this Article 24, this Lease shall not be affected by any such sale and Tenant agrees to attorn to the purchaser or assignee. If any security has been given by Tenant to secure the faithful performance of any of the covenants of this Lease, Landlord shall transfer or deliver said security, as such, to Landlord’s successor in interest and thereupon Landlord shall be discharged from any further liability with regard to said security.

25. ESTOPPEL CERTIFICATES. Within ten (10) days following any written request which Landlord may make from time to time, Tenant shall execute and deliver to Landlord or mortgagee or prospective mortgagee a sworn statement certifying: (a) the date of commencement of this Lease; (b) the fact that this Lease is unmodified and in full force and effect (or, if there have been modifications to this Lease, that this lease is in full force and effect, as modified, and stating the date and nature of such modifications); (c) the date to which the rent and other sums payable under this Lease have been paid; (d) the fact that there are no current defaults under this Lease by either Landlord or Tenant except as specified in Tenant’s statement; and (e) such other matters as may be requested by Landlord. Landlord and Tenant intend that any statement delivered pursuant to this Article 25 may be relied upon by any mortgagee, beneficiary or purchaser and Tenant shall be liable for all loss, cost or expense resulting from the failure of any sale or funding of any loan caused by any material misstatement contained in such estoppel certificate. Tenant irrevocably agrees that if Tenant fails to execute and deliver such certificate within such ten (10) day period Landlord or Landlord’s beneficiary or agent may execute and deliver such certificate on Tenant’s behalf, and that such certificate shall be fully binding on Tenant.

26. SURRENDER OF PREMISES.

26.1 Tenant shall, at least thirty (30) days before the last day of the Term, arrange to meet Landlord for a joint inspection of the Premises. In the event of Tenant’s failure to arrange such joint inspection to be held prior to vacating the Premises, Landlord’s inspection at or after Tenant’s vacating the Premises shall be conclusively deemed correct for purposes of determining Tenant’s responsibility for repairs and restoration.

26.2 At the end of the Term or any renewal of the Term or other sooner termination of this Lease, Tenant will peaceably deliver up to Landlord possession of the Premises, together with all improvements or additions upon or belonging to the same, by whomsoever made, in the same conditions received or first installed, broom clean and free of all debris, excepting only ordinary wear and tear and damage by fire or other casualty. Tenant may, and at Landlord’s request shall, at Tenant’s sole cost, remove upon termination of this Lease, any and all furniture, furnishings, movable partitions of less than full height from floor to ceiling, trade fixtures and other property installed by Tenant, title to which shall not be in or pass automatically to Landlord upon such termination, repairing all damage caused by such removal. Property not so removed shall, unless requested to be removed, be deemed abandoned by the Tenant and title to the same shall thereupon pass to Landlord under this Lease as by a bill of sale. All other alterations, additions and improvements in, on or to the Premises shall be dealt with and disposed of as provided in Article 6.

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26.3 All obligations of Tenant under this Lease not fully performed as of the expiration or earlier termination of the Term shall survive the expiration or earlier termination of the Term. In the event that Tenant’s failure to perform prevents Landlord from releasing the Premises, Tenant shall continue to pay rent pursuant to the provisions of Article 14 until such performance is complete. Upon the expiration or earlier termination of the Term, Tenant shall pay to Landlord the amount, as estimated by Landlord, necessary to repair and restore the Premises as provided in this Lease and/or to discharge Tenant’s obligation for unpaid amounts due or to become due to Landlord. All such amounts shall be used and held by Landlord for payment of such obligations of Tenant, with Tenant being liable for any additional costs upon demand by Landlord, or with any excess to be returned to Tenant after all such obligations have been determined and satisfied. Any otherwise unused Security Deposit shall be credited against the amount payable by Tenant under this Lease.

27. NOTICES. Any notice or document required or permitted to be delivered under this Lease shall be addressed to the intended recipient, shall be transmitted personally, by fully prepaid registered or certified United States Mail return receipt requested, or by reputable independent contract delivery service furnishing a written record of attempted or actual delivery, and shall be deemed to be delivered when tendered for delivery to the addressee at its address set forth on the Reference Page, or at such other address as it has then last specified by written notice delivered in accordance with this Article 27, or if to Tenant at either its aforesaid address or its last known registered office or home of a general partner or individual owner, whether or not actually accepted or received by the addressee.

28. TAXES PAYABLE BY TENANT. In addition to rent and other charges to be paid by Tenant under this Lease, Tenant shall reimburse to Landlord, upon demand, any and all taxes payable by Landlord (other than Federal, state and/or local net income taxes) whether or not now customary or within the contemplation of the parties to this Lease: (a) upon, allocable to, or measured by or on the gross or net rent payable under this Lease, including without limitation any gross income tax or excise tax levied by the State, any political subdivision thereof, or the Federal Government with respect to the receipt of such rent; (b) upon or with respect to the possession, leasing, operation, management, maintenance, alteration, repair, use or occupancy of the Premises or any portion thereof, including any sales, use or service tax imposed as a result thereof; (c) upon or measured by the Tenant’s gross receipts or payroll or the value of Tenant’s equipment, furniture, fixtures and other personal property of Tenant or leasehold improvements, alterations or additions located in the Premises; or (d) upon this transaction or any document to which Tenant is a party creating or transferring any interest of Tenant in this Lease or the Premises. In addition to the foregoing, Tenant agrees to pay, before delinquency, any and all taxes levied or assessed against Tenant and which become payable during the term hereof upon Tenant’s equipment, furniture, fixtures and other personal property of Tenant located in the Premises.

29. RELOCATION OF TENANT. Intentionally deleted.

30. DEFINED TERMS AND HEADINGS. The Article headings shown in this Lease are for convenience of reference and shall in no way define, increase, limit or describe the scope or intent of any provision of this Lease. Any indemnification or insurance of Landlord shall apply to and inure to the benefit of all the following “Landlord Entities”, being Landlord, Landlord’s investment manager, and the trustees, boards of directors, officers, general partners, beneficiaries, stockholders, employees and agents of each of them. Any option granted to Landlord shall also include or be exercisable by Landlord’s trustee, beneficiary, agents and employees, as the case may be. In any case where this Lease is signed by more than one person, the obligations under this Lease shall be joint and several The terms “Tenant” and “Landlord” or any pronoun used in place thereof shall indicate and include the masculine or feminine, the singular or plural number, individuals, firms or corporations, and each of their respective successors, executors, administrators and permitted assigns, according to the context hereof. The term “rentable area” shall mean the rentable area of the Premises or the Building as calculated by the Landlord on the basis of the plans and specifications of the Building including a proportionate share of any common areas. Tenant hereby accepts and agrees to be bound by the figures for the rentable space footage of the Premises and Tenant’s Proportionate Share shown on the Reference Page.

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31. TENANT’S AUTHORITY. If Tenant signs as a corporation each of the persons executing this Lease on behalf of Tenant represents and warrants that Tenant has been and is qualified to do business in the state in which the Building is located, that the corporation has full right and authority to enter into this Lease, and that all persons signing on behalf of the corporation were authorized to do so by appropriate corporate actions. If Tenant signs as a partnership, trust or other legal entity, each of the persons executing this Lease on behalf of Tenant represents and warrants that Tenant has complied with all applicable laws, rules and governmental regulations relative to its right to do business in the state and that such entity on behalf of the Tenant was authorized to do so by any and all appropriate partnership, trust or other actions. Tenant agrees to furnish promptly upon request a corporate resolution, proof of due authorization by partners, or other appropriate documentation evidencing the due authorization of Tenant to enter into this Lease.

32. COMMISSIONS. Each of the parties represents and warrants to the other that it has not dealt with any broker or finder in connection with this Lease, except as described on the Reference Page, and agrees to indemnify, defend and hold the other party harmless from and against any claims arising from the breach of the indemnifying party’s representation and warranty.

33. TIME AND APPLICABLE LAW. Time is of the essence of this Lease and all of its provisions. This Lease shall in all respects be governed by the laws of the state in which the Building is located.

34. SUCCESSORS AND ASSIGNS. Subject to the provisions of Article 9, the terms, covenants and conditions contained in this Lease shall be binding upon and inure to the benefit of the heirs, successors, executors, administrators and assigns of the parties to this Lease.

35. ENTIRE AGREEMENT. This Lease, together with its exhibits, contains all agreements of the parties to this Lease and supersedes any previous negotiations. There have been no representations made by the Landlord or understandings made between the parties other than those set forth in this Lease and its exhibits. This Lease may not be modified except by a written instrument duly executed by the parties to this Lease.

36. EXAMINATION NOT OPTION. Submission of this Lease shall not be deemed to be a reservation of the Premises. Landlord shall not be bound by this Lease until it has received a copy of this Lease duly executed by Tenant and has delivered to Tenant a copy of this Lease duly executed by Landlord, and until such delivery Landlord reserves the right to exhibit and lease the Premises to other prospective tenants. Notwithstanding anything contained in this Lease to the contrary, Landlord may withhold delivery of possession of the Premises from Tenant until such time as Tenant has paid to Landlord any security deposit required by Article 5, the first month’s rent as set forth in Article 3 and any sum owed pursuant to this Lease.

37. RECORDATION. Tenant shall not record or register this Lease or a short form memorandum hereof without the prior written consent of Landlord, and then shall pay all charges and taxes incident such recording or registration.

38. RENT SCHEDULE.

		Rentable Square		Rent				Monthly Installment
Period		Footage		Per Square Foot		Annual Rent		of Rent
10/15/01	9/30/03		31,119	$	6.00	$	186,714.00	$	15,559.50
10/1/03	9/30/05		31,119	$	6.25	$	194,493.75	$	16,207.81
10/1/05	10/31/06		31,119	$	6.50	$	202,273.50	$	16,856.13

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39. RENEWAL OPTION. Tenant shall, provided the Lease is in full force and effect and Tenant is not then in default under any of the other terms and conditions of the Lease at the time of notification or commencement, have one (1) option to renew this Lease for a term of five (5) years, for the portion of the Premises being leased by Tenant as of the date the renewal term is to commence, on the same terms and conditions set forth in the Lease, except as modified by the terms, covenants and conditions as set forth below:

39.1 If Tenant elects to exercise said option, then Tenant shall provide Landlord with written notice no earlier than the date which is fifteen (15) months prior to the expiration of the then current term of the Lease but no later than the date which is nine (9) months prior to the expiration of the then current term of this Lease. If Tenant fails to provide such notice, Tenant shall have no further or additional right to extend or renew the term of the Lease.

39.2 The Annual Rent and Monthly Installment in effect at the expiration of the then current term of the Lease shall be increased to reflect the current fair market rental for comparable space in the Building and in other similar buildings in the same rental market as of the date the renewal term is to commence, taking into account the specific provisions of the Lease which will remain constant. Landlord shall advise Tenant of the new Annual Rent and Monthly Installment for the Premises no later than thirty (30) days after receipt of Tenant’s written request therefor. Said request shall be made no earlier than thirty (30) days prior to the first date on which Tenant may exercise its option under this Paragraph. Said notification of the new Annual Rent may include a provision for its escalation to provide for a change in fair market rental between the time of notification and the commencement of the renewal term. If Tenant and Landlord are unable to agree on a mutually acceptable rental rate not later than sixty (60) days prior to the expiration of the then current term, then Landlord and Tenant shall each appoint a qualified MAI appraiser doing business in the area, in turn those two independent MAI appraisers shall appoint a third MAI appraiser and the majority shall decide upon the fair market rental for the Premises as of the expiration of the then current term. Landlord and Tenant shall equally share in the expense of this appraisal except that in the event the Annual Rent and Monthly Installment is found to be within fifteen percent (15%) of the original rate quoted by Landlord, then Tenant shall bear the full cost of all the appraisal process. In no event shall the Annual Rent and Monthly Installment for any option period be less than the Annual Rent and Monthly Installment in the preceding period.

39.3 This option is not transferable; the parties hereto acknowledge and agree that they intend that the aforesaid option to renew this Lease shall be “personal” to Tenant as set forth above and that in no event will any assignee or sublessee have any rights to exercise the aforesaid option to renew.

40. PARKING AND LOADING.

40.1 The Building has approximately 292 parking spaces. Tenant shall have the right to use 83 spaces, being its proportionate thereof.

40.2 Tenant shall have the exclusive use of four (4) loading docks as depicted on Exhibit A.

(THE NEXT ARTICLE IS ARTICLE 41)

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41. LIMITATION OF LANDLORD’S LIABILITY. Redress for any claim against Landlord under this Lease shall be limited to and enforceable only against and to the extent of Landlord’s interest in the Building. The obligations of Landlord under this Lease are not intended to and shall not be personally binding on, nor shall any resort be had to the private properties of, any of its trustees or board of directors and officers, as the case may be, its investment manager, the general partners thereof, or any beneficiaries, stockholders, employees, or agents of Landlord or the investment manager.

LANDLORD:		TENANT:
TMT 290 INDUSTRIAL PARK, INC., a Delaware nonprofit corporation		ASPEN AEROGELS, INC., a Delaware corporation
By:	RREEF Management Company, a Delaware corporation
By:	/s/ Eric Berke Eric Berke, District Manager	By:	/s/ Patrick J. Piper
		Title:	CFO
Dated:	10/11, 2001	Dated:	10/9, 2001

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EXHIBIT A — PREMISES

attached to and made a part of Lease bearing the

Lease Reference Date of August 20, 2001 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord and

ASPEN AEROGELS, INC., as Tenant

PREMISES

Exhibit A is intended only to show the general layout of the Premises as of the beginning of the Term of this Lease. It does not in any way supersede any of Landlord’s rights set forth in Section 17.2 with respect to arrangements and/or locations of public parts of the Building and changes in such arrangements and/or locations. It is not to be scaled; any measurements or distances shown should be taken as approximate.

EXHIBIT B — INITIAL ALTERATIONS

attached to and made a part of Lease bearing the

Lease Reference Date of August 20, 2001 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord and

ASPEN AEROGELS, INC., as Tenant

INITIAL ALTERATIONS

Landlord shall deliver the Premises in its “AS IS” condition, and shall have no obligation to construct any improvements or provide any funds or allowance for same. Landlord represents that the Building systems serving the Premises will be in good working order as of the Commencement Date. Existing rooftop HVAC units will be left in place and Landlord shall have no obligation to remove same.

Tenant may construct tenant improvements in conformance with Article 6 of the Lease.

So long as Tenant complies with Article 6 and the additional provisions of this Exhibit B, Tenant shall have the right to construct the following specific improvements:

1. One (1) CO₂ tank located on the exterior of the Building and adjacent to the Premises. The height of the tank may not exceed the height of the Building or twenty (20) feet, whichever is less.

2. One (1) cooling tower on the roof. The cooling towers all meet the following specifications:

• 80 inches high

• 86 inches in diameter

• Weight 642 pounds when dry, 1,588 pounds when wet

In addition, Landlord hereby agrees to the following alterations by Tenant and a contractor of Tenant’s choosing in the future and reasonably approved by Landlord, described below and to be detailed in complete plans and specifications submitted to Landlord for approval:

1) Installation of a concrete containment wall around our prospective material storage area that conforms to permitting guidelines.

2) Attach equipment to the ground throughout the Premises to comply with government and stricter internal safety guidelines. These include, without limitation, skids for the extraction system, equipment in the casting, gel mix and dispense, post processing and storage areas.

3) Installation of several hoods to be installed in the lab space, as well as in the casting, aging and loading, extraction and post processing areas. Wherever possible, these hoods will be merged to minimize the amount of vents needed through the roof.

4) Installation of pipes to enter the building from the cooling tower on the roof and the CO2 storage near the loading docks to the boiler room. A collection of supply piping between the loading dock area and the material storage area will also be needed. There will also likely need to be additional piping for enhanced pressurized air and vacuum from the boiler room to be distributed throughout the facility.

5) Concrete slab to be constructed to support the CO2 pump. Currently, this slab’s anticipated dimensions will be 10’X4’X20”.

6) Boiler room built adjacent to the extraction system, which will hold among other things, a boiler, a chiller, and a CO2 compressor.

7) Installation of at least 2 cranes will need to be installed off existing structural supports or the ceiling.

8) Installation of a series of conveyor belts may be needed between production departments.

9) The office and lab space requirements typical of an office and/or lab environment. (i.e. — offices, conference rooms, sinks etc)

10) Additional restroom may be necessary to comply with governmental guidelines.

11) Additional fire suppression capabilities might also be required.

All of the above must be in compliance with all federal, state and local laws, codes and ordinances regarding construction, maintenance and operation of same, and Tenant shall be responsible for obtaining all necessary permits and approvals, at Tenant’s sole cost. Both the tank and the cooling tower must be screened from view at street level. The exact location of all these improvements, and detailed plans and specifications for same, are subject to Landlord’s prior written approval. Without limiting the generality of the foregoing, any rooftop installations must be approved by and coordinated with Landlord and Landlord’s roofing contractor so as to avoid any impairment of any existing roof warranties, and Tenant acknowledges that access to the roof for installation and ongoing maintenance and operation will require that Tenant execute Landlord’s standard form of rooftop license agreement, substantially in the form of Exhibit D attached hereto. The provisions of paragraph 6.4 of the Lease shall apply to these improvements as improvements which Landlord may require Tenant to remove at the expiration of the Term of the Lease.

Without limiting the generality of the foregoing, items number 4, 7 and 11 above in particular will require stamped drawings by a structural engineer and must be approved by Landlord.

The provisions of paragraph 6.4 of the Lease shall apply to all of these improvements, alterations and additions as items which Landlord may require Tenant to remove at the expiration of the Term of the Lease. Tenant is hereby notified that the entire Premises must be restored to its original condition upon expiration or early termination of the Term of the Lease, including removal of all equipment and concrete slabs.

EXHIBIT C — RULES AND REGULATIONS

attached to and made a part of Lease bearing the

Lease Reference Date of August 20, 2001 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord and

ASPEN AEROGELS, INC., as Tenant

RULES AND REGULATIONS

1. No sign, placard, picture, advertisement, name or notice shall be installed or displayed on any part of the outside or inside of the Building without the prior written consent of the Landlord. Landlord shall have the right to remove, at Tenant’s expense and without notice, any sign installed or displayed in violation of this rule. All approved signs or lettering on doors and walls shall be printed, painted, affixed or inscribed at the expense of Tenant by a person or vendor chosen by Landlord.

2. If Landlord objects in writing to any curtains, blinds, shades or screens attached to or hung in or used in connection with any window or door of the Premises, Tenant shall immediately discontinue such use. No awning shall be permitted on any part of the Premises. Tenant shall not place anything or allow anything to be placed against or near any glass partitions or doors or windows which may appear unsightly, in the opinion of Landlord, from outside the Premises.

3. Tenant shall not obstruct any sidewalks, halls, passages, exits, entrances, elevators, escalators or stairways of the Building. The halls, passages, exits, entrances, shopping malls, elevators, escalators and stairways are not for the general public, and Landlord shall in all cases retain the right to control and prevent access to the Building of all persons whose presence in the judgment of Landlord would be prejudicial to the safety, character, reputation and interests of the Building and its tenants provided that nothing contained in this rule shall be construed to prevent such access to persons with whom any tenant normally deals in the ordinary course of its business, unless such persons are engaged in illegal activities. No tenant and no employee or invitee of any tenant shall go upon the roof of the Building, except as provided herein.

4. The directory of the Building will be provided exclusively for the display of the name and location of tenants only and Landlord reserves the right to exclude any other names therefrom.

5. Landlord will furnish Tenant free of charge with two keys to each door in the Premises. Landlord may make a reasonable charge for any additional keys, and Tenant shall not make or have made additional keys, and Tenant shall not alter any lock or install a new or additional lock or bolt on any door of its Premises. Tenant, upon the termination of its tenancy, shall deliver to Landlord the keys of all doors which have been furnished to Tenant, and in the event of loss of any keys so furnished, shall pay Landlord therefor.

6. If Tenant requires telegraphic, telephonic, burglar alarm or similar services, it shall first obtain, and comply with, Landlord’s instructions in their installation.

7. No equipment, materials, furniture, packages, supplies, merchandise or other property will be received in the Building or carried in the elevators except between such hours and in such elevators as may be designated by Landlord.

8. Landlord reserves the right to exclude from the Building between the hours of 6 p.m. and 7 a.m. the following day, or such other hours as may be established from time to time by Landlord, and on Sundays and legal holidays any person unless that person is known to the person or employee in charge of the Building and has a pass or is properly identified. Tenant shall be responsible for all persons for whom it requests passes and shall be liable to Landlord for all acts of such persons. Landlord shall not be liable for damages for any error with regard to the admission to or exclusion from the Building of any person.

C-1

9. Tenant shall close and lock the doors of its Premises and entirely shut off all water faucets or other water apparatus and electricity, gas or air outlets before Tenant and its employees leave the Premises. Tenant shall be responsible for any damage or injuries sustained by other tenants or occupants of the Building or by Landlord for noncompliance with this rule.

10. The toilet rooms, toilets, urinals, wash bowls and other apparatus shall not be used for any purpose other than that for which they were constructed, no foreign substance of any kind whatsoever shall be thrown into any of them, and the expense of any breakage, stoppage or damage resulting from the violation of this rule shall be borne by the Tenant who, or whose employees or invitees, shall have caused it.

11. Tenant shall not install any radio or television antenna, satellite dish, loudspeaker or other device on the roof or exterior walls of the Building. Tenant shall not interfere with radio or television broadcasting or reception from or in the Building or elsewhere.

12. Tenant shall not install, maintain or operate upon the Premises any vending machine.

13. Tenant shall store all its trash and garbage within its Premises [outside in dumptster]. Tenant shall not place in any trash box or receptacle any material which cannot be disposed of in the ordinary and customary manner of trash and garbage disposal. All garbage and refuse disposal shall be made in accordance with directions issued from time to time by Landlord.

14. No cooking shall be done or permitted by any Tenant on the Premises, except by the Tenant of Underwriters’ Laboratory approved microwave oven or equipment for brewing coffee, tea, hot chocolate and similar beverages shall be permitted provided that such equipment and use is in accordance with all applicable federal, state and city laws, codes, ordinances, rules and regulations.

15. Tenant shall not use the name of the Building in connection with or in promoting or advertising the business of Tenant except as Tenant’s address.

16. The requirements of Tenant will be attended to only upon appropriate application to the office of the Building by an authorized individual. Employees of Landlord shall not perform any work or do anything outside of their regular duties unless under special instruction form Landlord, and no employee of Landlord will admit any person (Tenant or otherwise) to any office without specific instructions from Landlord.

17. Landlord may waive any one or more of these Rules and Regulations for the benefit of any particular tenant or tenants, but no such waiver by Landlord shall be construed as a waiver of such Rules and Regulations in favor of any other tenant or tenants, nor prevent Landlord from thereafter enforcing any such Rules and Regulations against any or all of the tenants of the Building.

18. These Rules and Regulations are in addition to, and shall not be construed to in any way modify or amend, in whole or in part, the terms, covenants, agreements and conditions of any lease of premises in the Building.

19. Landlord reserves the right to make such other and reasonable rules and regulations as in its judgment may from time to time be needed for safety and security, for care and cleanliness of the Building and for the preservation of good order in and about the Building. Tenant agrees to abide by all such rules and regulations in this Exhibit C stated and any additional rules and regulations which are adopted.

20. Tenant shall be responsible for the observance of all of the foregoing rules by Tenant’s employees, agents, clients, customers, invitees and guests.

C-2

EXHIBIT D — HAZARDOUS MATERIALS EXHIBIT

attached to and made a part of Lease bearing the

Lease Reference Date of August 20, 2001 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord and

ASPEN AEROGELS, INC., as Tenant

Based on 3,000-5,000 Liter Plant (limited inventories)	(gallons)
Silbond H-5 or similar		5,000
Waterglass (NA Silicate)		8,500
EtOH or similar		17,300
NH4OH conc. (ammonia)		55
Alcoblak 300A or similar		110
2-propanol or similar		2,500
THF, Hexane or similar		250
PDMS or similar		50
HCL		960
HMDS, HMDSO or similar		500

Also Various Standard Laboratory Chemicals

Alcohols	Standard Lab Quantities
Acids	Standard Lab Quantities
Chemicals	Standard Lab Quantities
Bases	Standard Lab Quantities
Alkoxides	Standard Lab Quantities
Chlorides	Standard Lab Quantities
Silanes	Standard Lab Quantities

Note: All materials and the quantities thereof are subject to Tenant’s obtaining any required federal, state and/or local approvals and compliance with all applicable statutes, regulations, codes and ordinances. .

EXHIBIT E — FORM OF LETTER OF CREDIT

attached to and made a part of Lease bearing the

Lease Reference Date of August 20, 2001 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord and

ASPEN AEROGELS, INC., as Tenant

EXHIBIT F — ROOFTOP LICENSE AGREEMENT

attached to and made a part of Lease bearing the

Lease Reference Date of August 20, 2001 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord and

ASPEN AEROGELS, INC., as Tenant

LICENSE TO USE ROOFTOP SPACE

THIS LICENSE TO USE ROOFTOP SPACE (“License”) is entered into as of the     day of         , 2001, by and between                     (“Tenant”), and                     (“Landlord”).

1. Recitals. This License is made with reference to the following facts and objectives:

(a) Landlord leased to Tenant, and Tenant rented from Landlord, certain premises commonly known as                      (the “Premises”) located in the building commonly known as                     (the “Building:”), pursuant to a                      Lease dated for reference                     (the “Lease”).

(b) Tenant now wishes to install certain HVAC equipment on the roof of the Building, and has requested Landlord’s approval of same, and, accordingly, Landlord has required the execution and delivery of this License.

(c) All terms defined in the Lease retain their meaning herein, unless specified herein to the contrary.

(d) Now, therefore, in consideration of the premises herein contained and the detriments to be suffered by each of the parties, the parties hereby agree as follows:

2. License. Landlord hereby grants to Tenant a license (the “license”) to install, maintain and operate the HVAC system consisting of the equipment and materials, and having the operating characteristics specified in Exhibit A (“Rooftop HVAC Characteristics”) and to be located as shown on Exhibit B (“Rooftop HVAC Plan”). This system is collectively referred to herein as the “Rooftop HVAC Facilities.”

(a) Tenant shall pay to Landlord, as additional rent, on a monthly basis, the actual costs incurred by Landlord in furnishing electric power for the operation of the Rooftop HVAC Facilities. Landlord and Tenant agree that Tenant, at its sole cost and expense, shall install a meter to monitor Tenant’s use of electricity furnished by Landlord in the operation of the Rooftop HVAC Facilities. All amounts due under this paragraph shall constitute additional rent for purposes of the Lease.

(b) This license shall be revocable at Landlord’s discretion upon the occurrence of any of the following events: (i) termination of the Lease; (ii) default under the Lease; and (iii) default by Tenant of any of its obligations under this license. All of the Rooftop HVAC Facilities installed by Tenant shall be and remain the property of Tenant, and Tenant shall, prior to the expiration or termination of the Lease, remove the equipment (including all installation and anchoring hardware) and restore the roof to substantially the same condition existing prior to the installation of the equipment. Tenant shall be liable for, and shall promptly reimburse Landlord for, the cost of repairing all damage done to the Building by such removal, including filling and sealing any holes or cavities left by the removal of installation or anchoring hardware.

(c) Tenant shall, at its sole cost and expense, and at its sole risk, install the Rooftop HVAC Facilities in a good and workmanlike manner, and in compliance with all building, electric, communications, and safety codes, ordinances, standards, regulations and requirements of the municipal, state and Federal Governments.

F-1

Tenant shall deliver to Landlord Tenant’s plans and specifications for the installation of the Rooftop HVAC Facilities for review and approval by Landlord’s engineer not less than thirty (30) days prior to commencing installation. Tenant shall not commence installation of the Rooftop HVAC Facilities without the prior written consent of Landlord (which consent shall not be unreasonably withheld or delayed), and all phases of the installation shall be under the direct supervision of Landlord. Tenant shall obtain, at its sole cost and expense, prior to construction and work, any necessary federal, state, and municipal permits, licenses and approvals, copies of which will be delivered to Landlord prior to commencement of construction and work. In no event shall Tenant’s installation of the Rooftop HVAC Facilities damage the Building or existing structures on the Building, or interfere with the maintenance of the Building, any system currently serving the Building, or any radio or telecommunications equipment currently being operated from the Building. Tenant shall notify Landlord upon completion of the installation of the Rooftop HVAC Facilities, and Landlord shall have ten (10) days after installation in which to inspect the installation. Tenant shall not commence operation of the Rooftop HVAC Facilities until Landlord has approved the installation. Landlord’s review and approval of the plans and specifications for the installation of the Rooftop HVAC Facilities and Landlord’s supervision and inspection of such installation shall not be construed in any way as approval by Landlord of the adequacy or safety of the installation of the Rooftop HVAC Facilities or a waiver of any of Landlord’s rights hereunder, and Tenant shall be solely responsible for the adequacy and safety of the installation and operation of the Rooftop HVAC Facilities and solely liable for any damages or injury arising out of such installation and operation. Tenant shall pay to Landlord upon demand the cost of repairing any damage to the Building caused by such installation. The Rooftop HVAC Facilities shall be connected to Landlord’s power supply in strict compliance with all applicable building, electrical, fire and safety codes. Landlord shall not be liable to Tenant for any stoppages or shortages of electrical power furnished to the Rooftop HVAC Facilities because of any act, omission, or requirement of the public utility serving the Building, or the act or omission of any other tenant, licensee, or contractor of the Building, or for any other cause beyond the reasonable control of Landlord.

(d) Tenant must coordinate the installation, operation and maintenance with Landlord’s roofing contractor, to insure that the integrity of the roof is not compromised and the validity of the existing roof warranty is not impaired. No roof penetrations are permitted without the express written approval of Landlord and the roofing contractor. Tenant shall be solely liable for any damage to the roof or impairment or voiding of the roof warranty from any cause resulting from the installation, operation, maintenance, repair, inspection, use, or removal of the Rooftop HVAC Facilities equipment by Tenant or its agents, employees, representatives, contractors, or invitees, and shall indemnify, defend and hold Landlord harmless from and against any damages, claims, judgments, expenses and costs (including reasonable attorneys’ fees) arising in connection therewith.

(e) Landlord agrees that Tenant shall have continuous access to the Rooftop HVAC Facilities for the purpose of installing, operating, maintaining, repairing, and removing the Rooftop HVAC Facilities, provided, however, that such access shall be limited to authorized engineers of Tenant, or persons under their direct supervision. Tenant shall deliver to Landlord a list of Tenant’s authorized representatives, repair, maintenance, and engineering personnel prior to any access to the Rooftop HVAC Facilities, and those persons shall be required to sign in and out with Landlord’s security personnel when entering or exiting the Rooftop HVAC Facilities. Landlord shall have no responsibility or liability for the conduct or safety of any of Tenant’s representatives, repair, maintenance, and engineering personnel while in any part of the Building or the Rooftop HVAC Facilities, it being understood and agreed that Tenant shall be solely liable for any injury to or death of any such person from any cause resulting from the installation, operation, maintenance, repair, inspection, use, or removal of such equipment by Tenant or its agents, employees, representatives, contractors, or invitees.

(f) Tenant shall operate the equipment in strict compliance with Landlord’s rules and regulations, now or hereafter promulgated, and all applicable statutes, codes, rules, regulations, standards, and requirements of all federal, state, and local governmental boards, authorities, and agencies. Tenant’s equipment shall comply with all applicable safety standards, as modified form time to time, of any governing body with jurisdiction over Tenant’s operations. The installation, operation, and maintenance of the equipment shall at all times strictly comply with the technical standards approved by Landlord. The operation of the Rooftop HVAC Facilities shall not interfere with the maintenance or operation of the Building, or any system now or hereafter serving the Building, or the operation of any existing radio, microwave, satellite, or telecommunications equipment operated on or from the Building.

F-2

(g) During the term hereof, Landlord reserves the right to grant licenses for space on the roof of the Building and elsewhere on the Building, for the operation of radio, microwave, satellite, and telecommunications equipment by other tenants and licensees as well as other HVAC equipment; provided, however, that such other equipment shall not hinder or interfere with Tenant’s installation, operation, maintenance, or repair of the Rooftop HVAC Facilities.

3. Continuation. Other than as supplemented hereby, the Lease shall remain in full force and effect.

THE REST OF THIS PAGE IS INTENTIONALLY LEFT BLANK

F-3

4. Limitation Of Landlord’s Liability. Redress for any claim against Landlord under the Lease as supplemented hereby and under this License shall be limited to and enforceable only against and to the extent of Landlord’s interest in the Building. The obligations of Landlord under the Lease and the License are not intended to and shall not be personally binding on, nor shall any resort be had to the private properties of, any of its trustees or board of directors and officers, as the case may be, its investment manager, the general partners thereof, or any beneficiaries, stockholders, employees, or agents of Landlord or the investment manager.

IN WITNESS WHEREOF, the parties hereto have executed this License as of the day and year first written above.

LANDLORD: TENANT:                                         

F-4

EXHIBIT A TO LICENSE TO USE ROOFTOP SPACE

Rooftop HVAC Characteristics

EXHIBIT B TO LICENSE TO USE ROOFTOP SPACE

Rooftop HVAC Plan

EXHIBIT HM

(Premises HVAC Maintenance Requirements)

1. Check performance of all major components.

2. Lubricate moving parts as required.

3. Check refrigerant charges (during cooling season).

4. Inspect for oil and refrigerant leaks.

5. Check operating and safety controls.

6. Check pressures and temperatures.

7. Inspect condenser.

8. Inspect fans, motors, and starters.

9. Tighten electrical connections at equipment.

10. Test amperages and voltages.

11. Check belts and drives.

12. Changes oil and filters, or dryers, as required.

13. Check temperature on control system.

14. Thoroughly inspect heat exchanger.

FIRST AMENDMENT TO LEASE

THIS FIRST AMENDMENT TO LEASE, dated as of March 25, 2004 (this “Amendment”), is made by and between TMT 290 INDUSTRIAL PARK, INC., a Delaware nonprofit corporation, by RREEF Management Company, a Delaware corporation (“Landlord”), and ASPEN AEROGELS, INC., a Delaware corporation (“Tenant”), for certain premises located in the building commonly known as 30 Forbes Road, I-290 Industrial Park, Northborough, Massachusetts (the “Building”).

RECITALS:

A. Landlord and Tenant entered into that certain Multi-Tenant Industrial Net Lease dated for reference August 20, 2001 (the “Lease”) for approximately 31,119 rentable square feet in the Building (the “Original Premises”). The Original Premises is depicted on Exhibit A attached hereto.

B. Fiber Optic Network Solutions Corp., a Massachusetts corporation (“FONS”) currently leases the remainder of the Building consisting of approximately 80,458 rentable square feet, pursuant to a lease dated July 13, 2000, as amended (the “FONS Lease” and the portion of the Building subject to the FONS Lease, the “FONS Premises”). The FONS Premises is depicted on Exhibit A-1 attached hereto.

C. Tenant, as Subtenant, and FONS, as Sublandlord, with Landlord’s consent, have entered into a Sublease dated as of January     , 2004 (the “Sublease”), whereby Tenant has agreed to take occupancy of various portions of the FONS Premises over time, eventually occupying the entire FONS Premises (and, thus, the entire Building).

D. Tenant and Landlord wish to extend the Term of the Lease and to amend the Lease so as to expand the leased Premises by adding the FONS Premises to the Premises.

E. All terms, covenants and conditions contained in this Amendment shall have the same meaning as in the Lease, and, shall govern should a conflict exist with previous terms and conditions.

AGREEMENT:

NOW, THEREFORE, in consideration of the foregoing recitals and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, Landlord and Tenant hereby agree as follows:

1. FONS Premises. The “FONS Premises Commencement Date,” as used herein, is the earlier to occur of (i) June 1, 2004 or (ii) at Tenant’s option, the date of Landlord’s termination of the FONS Lease due to a default by FONS pursuant to the terms of the Lease and Landlord’s notice to Tenant of such termination. Effective as of the FONS Premises Commencement Date, the Leased Premises shall be expanded to include the FONS Premises. Accordingly, as of the FONS Premises Commencement Date, the Leased Premises shall consist of the Original Premises, plus the FONS Premises, being the entire rentable area of the Building having a total Premises rentable area of approximately 111,577 rentable square feet, as approximately depicted on Exhibit A-2 attached hereto. The FONS Premises shall be a part of the Premises for all purposes of the Lease, except as specifically provided herein to the contrary.

2. Term. The term of the Lease is hereby extended so as to expire on August 31, 2010 (the revised Termination Date).

3. Tenant’s Proportionate Share. As of the FONS Premises Commencement Date, Tenant’s Proportionate Share for the entire Premises will be 100.00%.

4. Annual Rent and Monthly Installment of Rent. The Annual Rent and Monthly Installment of Rent for the Original Premises only shall remain as per Article 38 of the Lease, through October 31, 2006. Commencing as of the FONS Premises Commencement Date and continuing through October 31, 2006, the Annual Rent and Monthly Installment of Rent for the FONS Premises only shall be as set forth in the following schedule, and commencing as of November 1, 2006 and continuing through the end of the Term as extended, rent for the entire Premises (Original Premises and FONS Premises) shall be as set forth in the following schedule:

Period		Rentable Square		Annual Rent				Monthly Installment
from	to	Footage		Per Square Foot		Annual Rent		of Rent
FPCD	10/31/2006		80,458	$	6.50	$	522,977.00	$	43,581.42
11/1/2006	8/31/2007		111,577	$	6.50	$	725,250.50	$	60,437.54
9/1/2007	8/31/2010		111,577	$	7.00	$	781,039.00	$	65,086.58

“FPCD” is the FONS Premises Commencement Date.

5. Restoration.

(a) Reference is made to Paragraphs 6.4 and 26.2 of the Lease. Notwithstanding anything therein to the contrary, but subject to subparagraph (b) below, Landlord may require that Tenant reimburse Landlord for the reasonable cost of demolishing the office improvements in the FONS Premises upon the expiration or sooner termination of the Term of the Lease, and restoring the entire FONS Premises to shell warehouse condition, repairing any damage caused by such demolition and restoration, provided that such demolition is not to prepare the FONS Premises for fit out for office use or uses other than warehouse (all such demolition, restoration and repair collectively referred to as the “Restoration”). Landlord must perform the Restoration within the six (6) month period following the Termination Date (“Restoration Period”) in order to be entitled to reimbursement. To secure its obligation under this paragraph, Tenant shall deposit with Landlord, not later than ten (10) days after the execution and delivery of this Amendment, an irrevocable letter of credit in the amount of $241,375.00 (the “Restoration LOC”). The Restoration LOC must comply with, and shall be governed by the terms of, Paragraph 5.2 of the Lease; except that (i) the reduction provisions of Paragraph 5.2.1 will not apply, (ii) the “End Date,” as that term is defined in Paragraph 5.2.3 of the Lease and as applied to the Restoration LOC, may not be not earlier than seven (7) months after the Termination Date, and (iii) Paragraph 5.2.8 will not apply. The total amount due by Tenant for the cost of the Restoration shall not exceed the amount of the Restoration LOC. The letter of credit must be in form acceptable to Landlord and its counsel. Said letter of credit is in addition to, and not in lieu of, the letter of credit provided for in Paragraph 5.2 of the Lease.

(b) Landlord shall only perform the Restoration should it determine, in its reasonable discretion, after engaging a third party reputable real estate broker familiar with the area to market and show the Premises to potential tenants. Landlord shall engage the broker as soon as reasonably practical after Tenant has not exercised its option to renew the Lease or within 12 months of termination of the Lease. In the event that the Landlord is unable, using good faith and due diligence, to obtain a tenant for the Premises, and Landlord determines that the Restoration is necessary or desirable in connection with the optimal re-leasing of the FONS Premises, Landlord may elect to demolish all or part of the office improvements. Prior to performing the Restoration, Landlord shall provide Tenant with its estimate of the cost and schedule thereof, and Tenant shall be afforded the opportunity to perform the Restoration, at its sole cost, if it demonstrates to Landlord’s reasonable satisfaction that Tenant can perform the restoration at a cost lower than Landlord’s estimate and complete same within the same time period. If Landlord performs the Restoration, Landlord shall provide Tenant evidence of the cost thereof by written notice (with reasonable supporting documentation) delivered not later than the end of the Restoration Period, and Landlord may then draw on the Restoration LOC if Tenant does not object to costs within ten (10) days of its receipt from Landlord. Upon (i) Landlord’s receipt of reimbursement in full for the cost of the Restoration, or (ii) Tenant’s completion of the Restoration and demonstration to Landlord’s reasonable satisfaction that the cost thereof has been fully paid and the Building is free of any mechanics’ liens arising out of the Restoration, Landlord shall return the unused portion of the Restoration LOC to Tenant. If Landlord does not perform the Restoration during the Restoration Period and timely notify Tenant of the cost thereof, Landlord shall return the Restoration LOC to Tenant.

2

6. Condition of Premises. Tenant acknowledges that Landlord shall have no obligation to perform any construction or make any additional improvements or alterations, or to afford any allowance to Tenant for improvements or alterations, in connection with this Amendment, either to the Original Premises or to the FONS Premises. Tenant acknowledges and agrees that all construction and improvements obligations of Landlord under the Lease (other than as set forth in this Amendment) have been performed in full and accepted. Tenant accepts the Original Premises and the FONS Premises in their “as is” condition, subject to Landlord’s performing such work.

7. Renewal Options. Article 39 remains in effect, except that the earliest notice date under Paragraph 39.1 shall be eighteen (18) months prior to the Termination Date, and the latest notice date shall be twelve (12) months prior to the Termination Date.

8. Condition Precedent. This Amendment, and Landlord’s obligations hereunder, are expressly conditioned upon Landlord and FONS entering into a lease termination agreement on terms and conditions acceptable to Landlord in its sole and absolute discretion. If, at any time, Landlord, in its sole and absolute discretion determines that the foregoing condition precedent cannot or will not be satisfied, Landlord may cancel this Amendment by written notice to Tenant, whereupon this Amendment shall be null and void and the Lease shall remain and continue in full force and effect without reference to this Amendment.

9. Notice of Lease/Subordination. The Landlord shall execute a Notice of Lease in the form attached hereto as Exhibit B, and consents to such being recorded, at Tenant’s sole cost and expense, in the appropriate Registry of Deeds. Prior to any such recording, Tenant shall deliver to Landlord a fully executed and notarized (but undated) instrument, in form and substance acceptable to Landlord, sufficient to release of record any and all right, title and interest of Tenant in and to the Building evidenced by such notice, and Landlord is hereby irrevocably authorized to date and record such instrument upon the expiration or early termination of the Lease. At Tenant’s request and at Tenant’s sole expense, Landlord shall make request of its current and any future mortgagee that it provide a non-disturbance agreement in favor of Tenant, but the failure to obtain such non-disturbance agreement shall not be a failure of condition of this Lease. Tenant shall reimburse Landlord for any fees and charges imposed by said mortgagee in connection with the non-disturbance agreement, as well as for reasonable attorneys’ fees and costs incurred by Landlord.

10. Tenant’s Authority. If Tenant signs as a corporation, partnership, trust or other legal entity each of the persons executing this Lease on behalf of Tenant represents and warrants that Tenant has been and is qualified to do business in the state in which the Building is located, that the entity has full right and authority to enter into this Lease, and that all persons signing on behalf of the entity were authorized to do so by appropriate actions. Tenant agrees to deliver to Landlord, simultaneously with the delivery of this Amendment, a corporate resolution, proof of due authorization by partners, opinion of counsel or other appropriate documentation reasonably acceptable to Landlord evidencing the due authorization of Tenant to enter into this Amendment.

11. Brokers. Landlord and Tenant each (i) represents and warrants to the other that it has not dealt with any broker or finder in connection with this Amendment, and (ii) agrees to defend, indemnify and hold the other harmless from and against any losses, damages, costs or expenses (including reasonable attorneys’ fees) incurred by such other party due to a breach of the foregoing warranty by the indemnifying party.

12. Incorporation. Except as modified herein, all other terms and conditions of the Lease shall continue in full force and effect and Tenant hereby ratifies and confirms its obligations thereunder. Tenant acknowledges that as of the date of the Amendment, Tenant (i) is not in default under the terms of the Lease; (ii) has no defense, set off or counterclaim to the enforcement by Landlord of the terms of the Lease; and (iii) is not aware of any action or inaction by Landlord that would constitute an Event of Default by Landlord under the Lease.

13. Limitation of Landlord Liability. Redress for any claim against Landlord under the Lease or this Amendment shall be limited to and enforceable only against and to the extent of Landlord’s interest in the Building. The obligations of Landlord under the Lease as amended are not intended to be and shall not be personally binding on, nor shall any resort be had to the private properties of, any of its or its investment manager’s trustees, directors, officers, partners, beneficiaries, members, stockholders, employees, or agents, and in no case shall Landlord be liable to Tenant hereunder for any lost profits, damage to business, or any form of special, indirect or consequential damages.

3

IN WITNESS WHEREOF, Landlord and Tenant have executed this Amendment as of the day and year first written above.

LANDLORD:		TENANT:
TMT 290 INDUSTRIAL PARK, INC., a Delaware nonprofit corporation		ASPEN AEROGELS, INC., a Delaware corporation
By:	RREEF Management Company, a Delaware corporation
By:	/s/ Robert Holmes Robert Holmes, District Manager	By:	/s/ Patrick J. Piper Patrick J. Piper
		Title:	CFO
Dated:	March 26, 2004	Date:	March 25, 2004

4

EXHIBIT A

attached to and made a part of the First Amendment to Lease

dated January 19, 2004 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord, and

ASPEN AEROGELS, INC., as Tenant

ORIGINAL PREMISES

Exhibits A, A-1 and A-2 are intended only to show the general layout of the expanded Leased Premises as of the FONS Premises Commencement Date. They do not in any way supersede any of Landlord’s rights set forth in the lease with respect to arrangements and/or locations of public parts of the Building and changes in such arrangements and/or locations. They are not to be scaled; any measurements or distances shown should be taken as approximate.

EXHIBIT A-1

attached to and made a part of the First Amendment to Lease

dated January 19, 2004 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord, and

ASPEN AEROGELS, INC., as Tenant

FONS PREMISES

EXHIBIT A-2

attached to and made a part of the First Amendment to Lease

dated January 19, 2004 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord, and

ASPEN AEROGELS, INC., as Tenant

LEASED PREMISES AFTER EXPANSION (ENTIRE BUILDING)

EXHIBIT B

attached to and made a part of the First Amendment to Lease

dated January 19, 2004 between

TMT 290 INDUSTRIAL PARK, INC., as Landlord, and

ASPEN AEROGELS, INC., as Tenant

NOTICE OF LEASE

In accordance with M.G.L. c. 183, Sec. 4, notice is hereby given of the following described lease:

Landlord:	TMT 290 Industrial Park, Inc., a Delaware non-profit corporation
Tenant:	Aspen Aerogels, Inc., a Delaware corporation
Date of Lease Execution:	October 11, 2001 and amended March 25, 2004
Description of Leased Premises:	Approximately 31,119 sq. ft. and subject to the First Amendment to Lease an additional 80,458 sq. ft., located at 30 Forbes Road, I-290 Industrial Park, Northborough, MA, together with the buildings, fixtures and other improvements to be erected and installed thereon.
Term of Lease:	The term of the Lease expires on August 31, 2010, unless sooner terminated in accordance with the terms thereof.

B-1

This instrument is executed as a notice of the aforesaid Lease and is not intended nor shall it be deemed to vary or govern the interpretation of the terms and conditions thereof.

WITNESS the execution hereof under seal by Landlord and Tenant as of the 25 day of March, 2004.

TMT 290 Industrial Park, Inc,, a Delaware Non-profit Corporation
By:	/s/ Robert Holmes
	RREEF Management Company, a Delaware Corporation
By:	/s/ Robert Holmes
ASPEN AEROGELS, INC.
By:	/s/ Patrick J. Piper
Name:	P.J. Piper
Title:	CFO
	Hereunto duly authorized

B-2

COMMONWEALTH OF MASSACHUSETTS

COUNTY OF             

On the      day of January, 2004 before me personally appeared the above-named             , the              of TMT 290 Industrial Park, Inc., known to me to be the party executing the foregoing instrument on behalf of said limited liability company and acknowledged said instrument so executed to be his free act and deed in said capacity and the free act and deed of said company.

Notary Public

My commission expires:

COMMONWEALTH OF MASSACHUSETTS

COUNTY OF             

On the      day of January, 2004 before me personally appeared the above-named             , the              of Aspen Aerogels, Inc., known to me to be the party executing the foregoing instrument on behalf of said corporation and acknowledged said instrument so executed to be his free act and deed in said capacity and the free act and deed of said corporation.

Notary Public

My commission expires:

B-3

SECOND AMENDMENT TO LEASE

THIS SECOND AMENDMENT TO LEASE (this “Amendment”) is made and entered into as of the 5th day of November 2009, by and between CABOT II — MA1M03, LLC, a Delaware limited liability company (“Landlord”) and ASPEN AEROGELS, INC., a Delaware corporation (“Tenant”).

WHEREAS, Landlord’s predecessor-in-interest and Tenant’s predecessor-in-interest entered into a certain Multi-Tenant Industrial Net Lease dated for reference as of August 20, 2001, as amended by First Amendment to Lease dated as of March 25, 2004 (as amended, the “Lease”), pursuant to which Tenant leases certain premises consisting of approximately 111,577 rentable square feet (the “Existing Premises”) in the building commonly known as 30 Forbes Road, Northborough, Massachusetts (the “Building”);

WHEREAS, Tenant desires to surrender approximately 28,800 rentable square feet of the Existing Premises (the “Surrendered Premises”) and Landlord has agreed to Tenant’s surrender of the Surrendered Premises on the terms set forth herein;

WHEREAS, the term of the Lease currently expires on August 31, 2010 and Tenant desires to extend the term of the Lease for an additional three (3) years and four (4) months and Landlord has agreed to extend the term of the Lease on the terms set forth herein;

WHEREAS, Landlord and Tenant desire to memorialize their understanding and modify the Lease consistent therewith;

NOW, THEREFORE, and for other good and valuable consideration, the receipt and adequacy of which is hereby acknowledged, Landlord and Tenant hereby agree as follows:

1. Lease Term. The term of the Lease shall be extended for a period of three (3) years and four (4) months and shall expire on December 31, 2013.

2. Surrendered Premises. As of December 31, 2009 (the “Surrender Date”), the Existing Premises shall be reduced by the Surrendered Premises. Tenant shall vacate the Surrendered Premises on or before the Surrender Date and shall deliver the Surrendered Premises to Landlord in accordance with Sections 6.4 and 26 of the Lease. Failure to vacate the Surrendered Premises by the Surrender Date shall be deemed a holding over pursuant to Section 14 of the Lease. Commencing on January 1, 2010 (the “Reduced Premises Commencement Date”), the “Premises” shall mean approximately 82,777 rentable square feet as shown on Exhibit A attached hereto.

3. Annual Rent. Commencing on the Reduced Premises Commencement Date, Tenant hereby agrees to pay to Landlord Monthly Installments of Rent for the Premises on the first day of each month in advance, without offset, deduction or prior demand as follows:

Time Period	Annual Rent Per Square Foot		Annual Rent		Monthly Installment of Rent
1.1.2010 — 8.31.2010	$	7.00	$	579,439.00	$	48,286.58
9.1.2010 — 8.31.2011	$	6.00	$	496,662.00	$	41,388.50	*
9.1.2011 — 8.31.2012	$	6.25	$	517,356.25	$	43,113.02
9.1.2012 — 12.31.2013	$	6.50	$	538,050.50	$	44,837.54

* Landlord and Tenant agree that the Monthly Installment of Rent shall be abated for the months of (i) September 2010 and (ii) October 2010. Notwithstanding the foregoing abatement, Tenant shall be obligated to pay Tenant’s Proportionate Share of Direct Expenses and Taxes for such months.

4. Tenant’s Proportionate Share. Commencing on the Reduced Premises Commencement Date, Tenant’s Proportionate Share shall be 74.19%.

5. As-Is Condition. In connection with this Amendment, Tenant is accepting the Premises in “as is” condition, and Landlord shall have no obligation to perform any work or construction to the Premises. Notwithstanding the foregoing, Landlord, at its sole cost and expense, shall demise the Premises (consisting of 82,777 rentable square feet) from the Existing Premises.

6. Brokers. Each party represents and warrants that it has dealt with no broker, agent, or other person other than CB Richard Ellis New England and Grubb & Ellis Company (collectively, the “Brokers”), in connection with this transaction and that no broker, agent or other person, other than the Brokers, brought about this transaction and each party agrees to indemnify and hold the other harmless from and against any claims by any other broker, agent or other person claiming a commission or other form of compensation by virtue of having dealt with the indemnifying party with regard to this leasing transaction. The provisions of this paragraph shall survive the termination of the Lease.

7. No Other Amendments. In all other respects, the terms and provisions of the Lease are ratified and reaffirmed hereby, are incorporated herein by this reference and shall be binding upon the parties to this Amendment.

8. Definitions. All capitalized terms used and not otherwise defined herein, shall have the meanings ascribed to them in the Lease.

9. Conflicts. Any inconsistencies or conflicts between the terms and provisions of the Lease and the terms and provisions of this Amendment shall be resolved in favor of the terms and provisions of this Amendment.

10. Execution. The submission of this Amendment shall not constitute an offer, and this Amendment shall not be effective and binding unless and until fully executed and delivered by each of the parties hereto. Tenant represents and warrants for itself that all requisite organizational action has been taken in connection with this transaction, and the individuals signing this Amendment on behalf of Tenant represent and warrant that they have been duly authorized to bind the Tenant by their signatures.

11. Counterparts. This Amendment may be executed in one or more counterparts, each of which shall be deemed an original but all of which together shall constitute one and the same instrument. Additionally, telecopied signatures may be used in place of original signatures on this Amendment. Landlord and Tenant intend to be bound by the signatures on the telecopied document, are aware that the other party will rely on the telecopied signatures, and hereby waive any defenses to the enforcement of the terms of this Amendment based on the form of signature.

SIGNATURES FOLLOW ON NEXT PAGE

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IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be duly executed, under seal, in multiple copies, each to be considered an original hereof, as of the day and year first above written.

LANDLORD:

CABOT II — MA1M03, LLC

By: Cabot Industrial Value Fund II Operating Partnership, L.P.

By:	/s/ Howard B. Hodgson, Jr.
Name:	Howard B. Hodgson, Jr.
Title:	Executive Vice President

TENANT:

ASPEN AEROGELS, INC.

By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Vice President, CFO & Treasurer

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EXHIBIT A

PREMISES

A-1

THIRD AMENDMENT TO LEASE

THIS THIRD AMENDMENT TO LEASE (this “Amendment”) is made and entered into as of the 19^th day of August, 2013, by and between CABOT II – MA1M03, LLC, a Delaware limited liability company (“Landlord”) and ASPEN AEROGELS, INC., a Delaware corporation (“Tenant”).

WHEREAS, Landlord’s predecessor-in-interest, TMT 290 Industrial Park, Inc., and Tenant’s predecessor-in-interest, Aspen Aerogels, Inc., entered into a certain Multi-Tenant Industrial Net Lease dated for reference as of August 20, 2001, as amended by that certain First Amendment to Lease (the “First Amendment”) dated as of March 25, 2004 and that certain Second Amendment to Lease dated as of November 5, 2009 (as amended, the “Lease”), pursuant to which Tenant leases certain premises consisting of approximately 82,777 rentable square feet (the “Premises”) in the building commonly known as 30 Forbes Road, Northborough, Massachusetts (the “Building”);

WHEREAS, the term of the Lease currently expires on December 31, 2013 and Tenant desires to extend the term of the Lease for an additional three (3) years and Landlord has agreed to extend the term of the Lease on the terms set forth herein;

WHEREAS, Landlord and Tenant desire to memorialize their understanding and modify the Lease consistent therewith;

NOW, THEREFORE, and for other good and valuable consideration, the receipt and adequacy of which is hereby acknowledged, Landlord and Tenant hereby agree as follows:

1. Lease Term. The term of the Lease shall be extended for a period of three (3) years and shall expire on December 31, 2016.

2. Annual Rent. Commencing on January 1, 2014, Tenant hereby agrees to pay to Landlord Monthly Installments of Rent for the Premises on the first day of each month in advance, without offset, deduction or prior demand as follows:

Time Period	Annual Rent Per Square Foot		Annual Rent		Monthly Installment of Rent
1.1.2014 – 12.31.2014	$	6.50	$	538,050.50	$	44,837.54
1.1.2015 – 12.31.2015	$	6.50	$	538,050.50	$	44,837.54
1.1.2016 – 12.31.2016	$	6.75	$	558,744.75	$	46,562.06

3. Renewal Options. All renewal options contained in the Lease, including without limitations, the rights contained in Article 39 of the Lease and Section 7 of the First Amendment are hereby deleted in their entirety and the following is substituted therefor:

Provided Tenant is not in default under this Lease and that no event or condition exists which with notice and the expiration of any race period would constitute a Default or an Event of Default under this Lease at the time the option may be exercised and at the time the Renewal Option (as defined below) commences, Landlord grants to Tenant one option (the “Renewal Option”) to extend this Lease with respect to all of the Premises or part thereof after accounting for Partial Surrender Option under Section 4 below, for one (1) additional period of two (2) years (a “Renewal Period”). The Renewal Option may be exercised by Tenant delivering written notice (the “Renewal Notice”) to Landlord at least nine (9) months but no more than twelve (12) months prior to the expiration of the then current Lease Term. In the event that Tenant fails timely to give such notice to Landlord, this Lease shall automatically terminate at the end of the Lease Term, and Tenant shall have no further option to extend the Lease Term. Time is of the essence in the exercise of the Renewal Option.

The Annual Rent (the “Renewal Rental Rate”) for the Renewal Period shall be as follows:

Time Period	Annual Rent Per Square Foot		Annual Rent		Monthly Installment of Rent
1.1.2017 – 12.31.2017	$	6.75	$	558,744.75	$	46,562.06
1.1.2018 – 12.31.2018	$	7.00	$	579,439.00	$	48,286.58

In connection with the exercise of such renewal Landlord and Tenant shall execute an amendment to this Lease, which amendment shall set forth the extended Lease Term and the Renewal Rental Rate. Except for the change in the rate of Annual Rent, the Renewal Period shall be subject to all of the terms and conditions of this Lease and the Premises shall be delivered in their then “as is” condition at the time the Renewal Period commences.

Neither any option granted to Tenant in this Lease or in any collateral instrument to renew or extend the Lease Term, nor the exercise of any such option by Tenant, shall prevent Landlord from exercising any option or right granted or reserved to Landlord in this Lease or in any collateral instrument or that Landlord may otherwise have, to terminate this Lease or any renewal or extension of the Lease Term either during the original Lease Term or during the renewed or extended term. Any renewal or extension right granted to Tenant shall be personal to Tenant or a permissible assignee and may not be exercised by any subtenant or legal representative of Tenant. Any termination of this Lease shall serve to terminate any such renewal or extension of the Lease Term, whether or not Tenant shall have exercised any option to renew or extend the Lease Term. No option granted to Tenant to renew or extend the Lease Term shall be deemed to give Tenant any further option to renew or extend.

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4. Partial Surrender Option. Tenant shall have the conditional right (the “Surrender Right”) to surrender an approximately 31,119 square foot portion of the Premises as more particularly depicted on Exhibit A attached hereto (the “Relinquished Premises”) upon Tenant’s satisfaction of the all of the following conditions precedent: (a) Tenant shall have delivered to Landlord, on either of January 1, 2015 or January 1, 2016, a written notice (the “Surrender Notice”) stating that Tenant elects to exercise this Surrender Right (Tenant will provide Landlord with informal notice of its intent to surrender the Relinquished Premises as soon as Tenant has determined to so surrender the same); (b) Tenant shall have paid to Landlord simultaneously with delivery of its Surrender Notice, a termination fee (the “Termination Fee”) equal to $16,489.49 (with respect to a Surrender Notice delivered January 1, 2015) or $5,773.23 (with respect to a Surrender Notice delivered January 1, 2016) and (c) on or prior to the date of the Surrender Notice, Tenant shall, at Tenant’s sole cost and expense, restore the Relinquished Premises to the Surrender Condition (as hereinafter defined). Provided that Tenant has complied with the foregoing, and further provided Tenant is not in default under this Lease and that no event or condition exists which with notice, and the expiration of any grace period would constitute an event of default under this Lease either on the date of Tenant’s delivery of the Surrender Notice or on the Surrender Effective Date (as hereinafter defined), then the Premises shall be contracted to omit the Relinquished Premises effective on the date which is six (6) months following the date of the Surrender Notice (June 30, 2015 (with respect to a Surrender Notice delivered January 1, 2015) or June 30, 2016 (with respect to a Surrender Notice delivered January 1, 2016), respectively) (the “Surrender Effective Date”). Time is of the essence with respect to the provisions of this Section 4.

Provided that Tenant has surrendered the Relinquished Premises and delivered the same to Landlord in Surrender Condition, effective on the Surrender Effective Date, Tenant’s Proportionate Share of the Direct Expenses and Taxes shall be reduced to 46.30% and the Annual Rent shall be proportionately reduced to reflect the surrender of Relinquished Premises.

As used herein, “Surrender Condition” shall mean restoration of the Relinquished Premises to shell warehouse condition (except for the office space in the front of the Relinquished Premises, which office space must be restored to broom clean condition, free of any and all debris, furniture, boxes and other personal property of any nature), broom clean and free of all debris, personal property, alterations, improvements, partitions, trade fixtures, concrete slabs and manufacturing equipment installed by or on behalf of Tenant and in connection therewith Tenant shall repair any material damage caused by removal of the such debris, personal property, furniture, partitions, alterations, improvements, partitions, trade fixtures, concrete slabs and manufacturing equipment provided, however, that Tenant shall not be required to wax or seal the floors or paint the walls.

5. As-Is Condition. In connection with this Amendment, Tenant is accepting the Premises in “as is” condition, and Landlord shall have no obligation to perform any work or construction to the Premises.

6. Brokers. Each party represents and warrants that it has dealt with no broker, agent, or other person other than CBRE, Inc. and Newmark Grubb Knight Frank (collectively, the “Brokers”), in connection with this transaction and that no broker, agent or other person, other than the Brokers, brought about this transaction and each party agrees to indemnify and hold the other harmless from and against any claims by any other broker, agent or other person claiming a commission or other form of compensation by virtue of having dealt with the indemnifying party with regard to this leasing transaction. The provisions of this paragraph shall survive the termination of the Lease.

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7. Parking. Article 40 of the Lease is hereby amended, so that the Tenant has the right to at least 216 of the 292 parking spaces or, as of the Surrender Effective Date, 132 of the 292 parking spaces if the Relinquished Space is surrendered pursuant to Section 4 above.

8. No Other Amendments. In all other respects, the terms and provisions of the Lease are ratified and reaffirmed hereby, are incorporated herein by this reference and shall be binding upon the parties to this Amendment.

9. Definitions. All capitalized terms used and not otherwise defined herein, shall have the meanings ascribed to them in the Lease. The term “Lease” shall include this Amendment and all recitals, schedules, and exhibits included herein or attached hereto.

10. Conflicts. Any inconsistencies or conflicts between the terms and provisions of the existing Lease and the terms and provisions of this Amendment shall be resolved in favor of the terms and provisions of this Amendment.

11. Execution. The submission of this Amendment shall not constitute an offer, and this Amendment shall not be effective and binding unless and until fully executed and delivered by each of the parties hereto. Tenant represents and warrants for itself that all requisite organizational action has been taken in connection with this transaction, and the individuals signing this Amendment on behalf of Tenant represent and warrant that they have been duly authorized to bind the Tenant by their signatures.

12. Counterparts. This Amendment may be executed in one or more counterparts, each of which shall be deemed an original but all of which together shall constitute one and the same instrument. Additionally, telecopied signatures may be used in place of original signatures on this Amendment. Landlord and Tenant intend to be bound by the signatures on the telecopied document, are aware that the other party will rely on the telecopied signatures, and hereby waive any defenses to the enforcement of the terms of this. Amendment based on the form of signature.

SIGNATURES FOLLOW ON NEXT PAGE

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IN WITNESS WHEREOF, Landlord and Tenant have caused this Amendment to be duly executed, under seal, in multiple copies, each to be considered an original hereof, as of the day and year first above written.

LANDLORD:

CABOT II – MA1MO3, LLC

By: Cabot Industrial Value Fund II Operating Partnership, L.P.

	By:	/s/ Janine M. Cobb
	Name:	Janine M. Cobb
	Title:	Senior Vice President
TENANT:
ASPEN AEROGELS, INC.
	By:	/s/ John F. Fairbanks
	Name:	John F. Fairbanks
	Title:	Vice President and Chief Financial Officer

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EXHIBIT A

RELINQUISHED PREMISES

A-1

EX-10.4

Exhibit 10.4

LOAN AND SECURITY AGREEMENT

THIS LOAN AND SECURITY AGREEMENT (this “Agreement”) dated as of the Effective Date between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (“Borrower”), provides the terms on which Bank shall lend to Borrower and Borrower shall repay Bank. The parties agree as follows:

1 ACCOUNTING AND OTHER TERMS

Accounting terms not defined in this Agreement shall be construed following GAAP. Calculations and determinations must be made following GAAP. Capitalized terms not otherwise defined in this Agreement shall have the meanings set forth in Section 13. All other terms contained in this Agreement, unless otherwise indicated, shall have the meaning provided by the Code to the extent such terms are defined therein.

2 LOAN AND TERMS OF PAYMENT

2.1 Promise to Pay. Borrower hereby unconditionally promises to pay Bank the outstanding principal amount of all Credit Extensions and accrued and unpaid interest thereon as and when due in accordance with this Agreement.

2.1.1 Revolving Advances.

(a) Availability. Subject to the terms and conditions of this Agreement and to deduction of Reserves, following the Account Transition Period, Bank shall make Advances not exceeding the Availability Amount. Amounts borrowed under the Revolving Line may be repaid, and prior to the Revolving Line Maturity Date, reborrowed, subject to the applicable terms and conditions precedent herein.

(b) Termination; Repayment. The Revolving Line terminates on the Revolving Line Maturity Date, when the principal amount of all Advances, the unpaid interest thereon, and all other Obligations relating to the Revolving Line shall be immediately due and payable.

2.1.2 Letters of Credit Sublimit.

(a) As part of the Revolving Line and subject to deduction of Reserves, following the Account Transition Period, Bank shall issue or have issued Letters of Credit denominated in Dollars or a Foreign Currency for Borrower’s account. The aggregate Dollar Equivalent amount utilized for the issuance of Letters of Credit shall at all times reduce the amount otherwise available for Advances under the Revolving Line. The aggregate Dollar Equivalent of the face amount of outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve) may not exceed the lesser of (A) Two Million Dollars ($2,000,000), minus (i) the sum of all amounts used for Cash Management Services, and minus (ii) the FX Reduction Amount, or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances (including any amounts used for Cash Management Services), and minus (ii) the FX Reduction Amount.

(b) If, on the Revolving Line Maturity Date (or the effective date of any termination of this Agreement), there are any outstanding Letters of Credit, then on such date Borrower shall provide to Bank cash collateral in an amount equal to 105% of the Dollar Equivalent of the face amount of all such Letters of Credit plus all interest, fees, and costs due or to become due in connection therewith (as estimated by Bank in its good faith business judgment), to secure all of the Obligations relating to such Letters of Credit. All Letters of Credit shall be in form and substance acceptable to Bank in its sole discretion and shall be subject to the terms and conditions of Bank’s standard Application and Letter of Credit Agreement (the “Letter of Credit Application”). Borrower agrees to execute any further documentation in connection with the Letters of Credit as Bank may reasonably request. Borrower further agrees to be bound by the regulations and interpretations of the issuer of any Letters of Credit guarantied by Bank and opened for Borrower’s account or by Bank’s interpretations of any Letter of Credit issued by Bank for Borrower’s account, and Borrower understands and agrees that Bank shall not be liable for any error, negligence, or mistake, whether of omission or commission, in following Borrower’s instructions or those contained in the Letters of Credit or any modifications, amendments, or supplements thereto.

(c) The obligation of Borrower to immediately reimburse Bank for drawings made under Letters of Credit shall be absolute, unconditional, and irrevocable, and shall be performed strictly in accordance with the terms of this Agreement, such Letters of Credit, and the Letter of Credit Application.

(d) Borrower may request that Bank issue a Letter of Credit payable in a Foreign Currency. If a demand for payment is made under any such Letter of Credit, Bank shall treat such demand as an Advance to Borrower of the Dollar Equivalent of the amount thereof (plus fees and charges in connection therewith such as wire, cable, SWIFT or similar charges).

(e) To guard against fluctuations in currency exchange rates, upon the issuance of any Letter of Credit payable in a Foreign Currency, Bank shall create a reserve (the “Letter of Credit Reserve”) under the Revolving Line in an amount equal to ten percent (10%) of the face amount of such Letter of Credit. The amount of the Letter of Credit Reserve may be adjusted by Bank from time to time to account for fluctuations in the exchange rate. The availability of funds under the Revolving Line shall be reduced by the amount of such Letter of Credit Reserve for as long as such Letter of Credit remains outstanding.

2.1.3 Foreign Exchange Sublimit. As part of the Revolving Line and subject to the deduction of Reserves, following the Account Transition Period, Borrower may enter into foreign exchange contracts with Bank under which Borrower commits to purchase from or sell to Bank a specific amount of Foreign Currency (each, a “FX Forward Contract”) on a specified date (the “Settlement Date”). FX Forward Contracts shall have a Settlement Date of at least one (1) FX Business Day after the contract date. The aggregate amount of FX Forward Contracts at any one time may not exceed ten (10) times the lesser of (A) Two Million Dollars ($2,000,000), minus (i) the sum of all amounts used for Cash Management Services, and minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances (including any amounts used for Cash Management Services), and minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve). The amount otherwise available for Credit Extensions under the Revolving Line shall be reduced by an amount equal to ten percent (10%) of each outstanding FX Forward Contract (the “FX Reduction Amount”). Any amounts needed to fully reimburse Bank for any amounts not paid by Borrower in connection with FX Forward Contracts will be treated as Advances under the Revolving Line and will accrue interest at the interest rate applicable to Advances.

2.1.4 Cash Management Services Sublimit. Borrower may, following the Account Transition Period, use the Revolving Line for Bank’s cash management services, which may include merchant services, direct deposit of payroll, business credit card, and check cashing services identified in Bank’s various cash management services agreements (collectively, the “Cash Management Services”), in an aggregate amount not to exceed the lesser of (A) Two Million Dollars ($2,000,000), minus (i) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), and minus (ii) the FX Reduction Amount, or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances, minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), and minus (iii) the FX Reduction Amount. Any amounts Bank pays on behalf of Borrower for any Cash Management Services will be treated as Advances under the Revolving Line and will accrue interest at the interest rate applicable to Advances.

2.2 Overadvances. If, at any time, the sum of (a) the outstanding principal amount of any Advances (including any amounts used for Cash Management Services and the outstanding principal amount of any EXIM Loans); plus (b) the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve); plus (c) the FX Reduction Amount exceeds the lesser of either the Revolving Line or the Borrowing Base (such excess amount being an “Overadvance”), Borrower shall immediately pay to Bank in cash such Overadvance. Without limiting Borrower’s obligation to repay Bank any amount of the Overadvance, Borrower agrees to pay Bank interest on the outstanding amount of any Overadvance, on demand, at the Default Rate.

2.3 Payment of Interest on the Credit Extensions.

(a) Interest Rate; Advances. Subject to Section 2.3(b), the principal amount outstanding under the Revolving Line shall accrue interest at a floating per annum rate equal to Prime Rate plus one percent (1.00%); provided, however, when Borrower is at or above the Liquidity Threshold, the principal amount outstanding under the Revolving Line shall accrue interest at a floating per annum rate equal to the Prime Rate plus one-half percent (0.50%). Such interest shall in any event be payable monthly, in arrears, in accordance with Section 2.3(f) below.

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(b) Default Rate. Immediately upon the occurrence and during the continuance of an Event of Default, Obligations shall bear interest at a rate per annum which is four percentage points (4.00%) above the rate that is otherwise applicable thereto (the “Default Rate”) unless Bank otherwise elects from time to time in its sole discretion to impose a smaller increase. Fees and expenses which are required to be paid by Borrower pursuant to the Loan Documents (including, without limitation, Bank Expenses) but are not paid when due shall bear interest until paid at a rate equal to the highest rate applicable to the Obligations. Payment or acceptance of the increased interest rate provided in this Section 2.3(b) is not a permitted alternative to timely payment and shall not constitute a waiver of any Event of Default or otherwise prejudice or limit any rights or remedies of Bank.

(c) Adjustment to Interest Rate. Changes to the interest rate of any Credit Extension based on changes to the Prime Rate shall be effective on the effective date of any change to the Prime Rate and to the extent of any such change.

(d) Computation; 360-Day Year. In computing interest, the date of the making of any Credit Extension shall be included and the date of payment shall be excluded; provided, however, that if any Credit Extension is repaid on the same day on which it is made, such day shall be included in computing interest on such Credit Extension. Interest shall be computed on the basis of a 360-day year for the actual number of days elapsed.

(e) Debit of Accounts. Bank may debit any of Borrower’s deposit accounts, including the Designated Deposit Account, for principal and interest payments or any other amounts Borrower owes Bank when due. These debits shall not constitute a set-off.

(f) Payment; Interest Computation; Float Charge. Interest is payable monthly on the last calendar day of each month. In computing interest on the Obligations, all Payments received after 12:00 noon Eastern time on any day shall be deemed received on the next Business Day. In addition, Bank shall be entitled to charge Borrower a “float” charge in an amount equal to three (3) Business Days interest, at the interest rate applicable to the Advances, on all Payments received by Bank; provided, that when Borrower is at or above the Liquidity Threshold, such “float” charge shall not apply. The float charge for each month shall be payable on the last day of the month. Bank shall not, however, be required to credit Borrower’s account for the amount of any item of payment which is unsatisfactory to Bank in its good faith business judgment, and Bank may charge Borrower’s Designated Deposit Account for the amount of any item of payment which is returned to Bank unpaid.

2.4 Fees. Borrower shall pay to Bank:

(a) Commitment Fee. A fully earned, non refundable commitment fee of Seventy Five Thousand Dollars ($75,000), payable on the Effective Date;

(b) Anniversary Fee. A fully earned, non refundable anniversary fee of Twenty Seven Thousand Five Hundred Dollars ($27,500), payable on the date that is three hundred sixty five (365) days after the Effective Date

(c) Letter of Credit Fee. Bank’s customary fees and expenses for the issuance or renewal of Letters of Credit, (including, without limitation, a letter of credit fee of two percent (2.00%) per annum of the Dollar Equivalent of the face amount of each Letter of Credit issued), upon the issuance of such Letter of Credit, each anniversary of the issuance during the term of such Letter of Credit, and upon the renewal of such Letter of Credit by Bank;

(d) Unused Revolving Line Facility Fee. A fee (the “Unused Revolving Line Facility Fee”), payable quarterly, in arrears, following the Account Transition Period, in an amount equal to one-half percent (0.50%) per annum of the average unused portion of the Revolving Line. The unused portion of the Revolving Line, for purposes of this calculation, shall equal the difference between (x) the Revolving Line amount (as it may be reduced from time to time) and (y) the average for the period of the daily closing balance of the Revolving Line outstanding plus the sum of the aggregate amount of outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve, plus the sum of any Reserves). Borrower shall not be entitled to any credit, rebate or repayment of any Unused Revolving Line Facility Fee previously earned by Bank pursuant to this Section notwithstanding any termination of the Agreement or the suspension or termination of Bank’s obligation to make loans and advances hereunder; and

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(e) Bank Expenses. All Bank Expenses (including reasonable attorneys’ fees and expenses for documentation and negotiation of this Agreement) incurred through and after the Effective Date, when due.

2.5 Payments; Application of Payments.

(a) All payments (including prepayments) to be made by Borrower under any Loan Document shall be made in immediately available funds in U.S. Dollars, without setoff or counterclaim, before 12:00 noon Eastern time on the date when due. Payments of principal and/or interest received after 12:00 noon Eastern time are considered received at the opening of business on the next Business Day. When a payment is due on a day that is not a Business Day, the payment shall be due the next Business Day, and additional fees or interest, as applicable, shall continue to accrue until paid.

(b) Subject to Section 6.3(c), Bank shall apply the whole or any part of collected funds against the Revolving Line or credit such collected funds to a depository account of Borrower with Bank (or an account maintained by an Affiliate of Bank), the order and method of such application to be in the sole discretion of Bank. Borrower shall have no right to specify the order or the accounts to which Bank shall allocate or apply any payments required to be made by Borrower to Bank or otherwise received by Bank under this Agreement when any such allocation or application is not specified elsewhere in this Agreement.

3 CONDITIONS OF LOANS

3.1 Conditions Precedent to Initial Credit Extension. Bank’s obligation to make the initial Credit Extension is subject to the condition precedent that Bank shall have received, in form and substance reasonably satisfactory to Bank, such documents, and completion of such other matters, as Bank may reasonably deem necessary or appropriate, including, without limitation:

(a) duly executed original signatures to the Loan Documents;

(b) duly executed original signatures to the Control Agreements, if any;

(c) Borrower’s Operating Documents and a good standing certificate of Borrower certified by the Secretary of State of the State(s) of Delaware, together with any certificates of foreign qualifications from each jurisdiction in which Borrower is qualified, each dated as of a date no earlier than thirty (30) days prior to the Effective Date;

(d) duly executed original signatures to the Secretary’s Certificate with completed Borrowing Resolutions for Borrower;

(e) the PJC Intercreditor Agreement by PJC Capital in favor of Bank, together with the duly executed original signatures thereto;

(f) [Reserved];

(g) [Reserved];

(h) certified copies, dated as of a recent date, of financing statement searches, as Bank shall request, accompanied by written evidence (including any UCC termination statements) that the Liens indicated in any such financing statements either constitute Permitted Liens or have been or, in connection with the initial Credit Extension, will be terminated or released;

(i) the Perfection Certificates of Borrower and Guarantor, together with the duly executed original signatures thereto;

(j) a landlord’s consent in favor of Bank for 30 Forbes Road, Building B, Northborough, Massachusetts 01532 and for 1 Dexter Road, East Providence, Rhode Island, by each landlord thereof, together with the duly executed original signatures thereto;

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(k) [Reserved];

(l) a legal opinion of Borrower’s counsel, in form and substance acceptable to Bank, in its reasonable discretion, dated as of the Effective Date together with the duly executed original signature thereto;

(m) the duly executed original signatures to the Guaranty Agreement and the Security Agreement, together with a Secretary’s Certificate and duly executed original signatures to the completed Borrowing Resolutions for Guarantor;

(n) evidence satisfactory to Bank that the insurance policies required by Section 6.7 hereof are in full force and effect, together with appropriate evidence showing lender loss payable and/or additional insured clauses and cancellation notice to Bank (or endorsements reflecting the same) in favor of Bank; and

(o) payment of the fees and Bank Expenses then due as specified in Section 2.4 hereof.

3.2 Conditions Precedent to all Credit Extensions. Bank’s obligation to make each Credit Extension, including the initial Credit Extension, is subject to the following conditions precedent:

(a) except as otherwise provided in Section 3.4, timely receipt of an executed Transaction Report;

(b) the representations and warranties in this Agreement shall be true, accurate, and complete in all material respects on the date of the Transaction Report and on the Funding Date of each Credit Extension; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date, and no Default or Event of Default shall have occurred and be continuing or result from the Credit Extension. Each Credit Extension is Borrower’s representation and warranty on that date that the representations and warranties in this Agreement remain true, accurate, and complete in all material respects; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date; and

(c) in Bank’s sole discretion, there has not been any material impairment in the general affairs, management, results of operation, financial condition or the prospect of repayment of the Obligations, or any material adverse deviation by Borrower from the most recent business plan of Borrower presented to and accepted by Bank.

3.3 Covenant to Deliver. Borrower agrees to deliver to Bank each item required to be delivered to Bank under this Agreement as a condition precedent to any Credit Extension. Borrower expressly agrees that a Credit Extension made prior to the receipt by Bank of any such item shall not constitute a waiver by Bank of Borrower’s obligation to deliver such item, and the making of any Credit Extension in the absence of a required item shall be in Bank’s sole discretion.

3.4 Procedures for Borrowing; Advances. Subject to the prior satisfaction of all other applicable conditions to the making of an Advance set forth in this Agreement, to obtain an Advance (other than Advances under Sections 2.1.2 or 2.1.4), Borrower shall notify Bank (which notice shall be irrevocable) by electronic mail, facsimile, or telephone by 12:00 noon Eastern time on the Funding Date of the Advance. Together with any such electronic or facsimile notification, Borrower shall deliver to Bank by electronic mail or facsimile a completed Transaction Report executed by a Responsible Officer or his or her designee. Bank may rely on any telephone notice given by a person whom Bank believes is a Responsible Officer or designee. Bank shall credit Advances to the Designated Deposit Account. Bank may make Advances under this Agreement based on instructions from a Responsible Officer or his or her designee or without instructions if the Advances are necessary to meet Obligations which have become due.

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4 CREATION OF SECURITY INTEREST

4.1 Grant of Security Interest. Borrower hereby grants Bank, to secure the payment and performance in full of all of the Obligations, a continuing security interest in, and pledges to Bank, the Collateral, wherever located, whether now owned or hereafter acquired or arising, and all proceeds and products thereof.

4.2 Priority of Security Interest. Borrower represents, warrants, and covenants that the security interest granted herein is and shall at all times continue to be a first priority perfected security interest in the Collateral (subject only to Permitted Liens that may have superior priority to Bank’s Lien under this Agreement or the Export-Import Agreement). If Borrower shall acquire a commercial tort claim, Borrower shall promptly notify Bank in a writing signed by Borrower of the general details thereof and grant to Bank in such writing a security interest therein and in the proceeds thereof, all upon the terms of this Agreement, with such writing to be in form and substance reasonably satisfactory to Bank.

If this Agreement is terminated, Bank’s Lien in the Collateral shall continue until the Obligations (other than inchoate indemnity obligations) are repaid in full in cash. Upon payment in full in cash of the Obligations and at such time as Bank’s obligation to make Credit Extensions has terminated, Bank shall, at Borrower’s sole cost and expense, release its Liens in the Collateral and all rights therein shall revert to Borrower.

Notwithstanding the foregoing, it is expressly acknowledged and agreed that the security interest created in this Agreement only with respect to Export-Related Accounts Receivable, Export-Related Inventory and Export-Related General Intangibles (as such terms are defined in the Export-Import Agreement) is subject to and subordinate to the security interest granted to Bank in the Export-Import Agreement with respect to such Export-Related Accounts Receivable, Export-Related Inventory and Export-Related General Intangibles.

4.3 Authorization to File Financing Statements. Borrower hereby authorizes Bank to file financing statements, without notice to Borrower, with all appropriate jurisdictions to perfect or protect Bank’s interest or rights hereunder, including a notice that any disposition of the Collateral, by either Borrower or any other Person not in accordance with this Agreement, may be deemed to violate the rights of Bank under the Code.

5 REPRESENTATIONS AND WARRANTIES

Borrower represents and warrants as follows:

5.1 Due Organization; Authorization; Power and Authority. Borrower and each of its Subsidiaries are duly existing and in good standing as a Registered Organization in its jurisdiction of formation and each is qualified and licensed to do business and each is in good standing in any jurisdiction in which the conduct of each of its business or its ownership of property requires that it be qualified except where the failure to do so could not reasonably be expected to have a material adverse effect on Borrower’s business. In connection with this Agreement, Borrower has delivered to Bank completed certificates each signed by Borrower and Guarantor, respectively, entitled “Perfection Certificate”. Borrower represents and warrants to Bank that (a) Borrower’s exact legal name is that indicated on the Perfection Certificate and on the signature page hereof; (b) Borrower is an organization of the type and is organized in the jurisdiction set forth in the Perfection Certificate; (c) the Perfection Certificate accurately sets forth Borrower’s organizational identification number or accurately states that Borrower has none; (d) the Perfection Certificate accurately sets forth Borrower’s place of business, or, if more than one, its chief executive office as well as Borrower’s mailing address (if different than its chief executive office); (e) except as set forth on the Perfection Certificate, Borrower (and each of its predecessors) has not, in the past five (5) years, changed its jurisdiction of formation, organizational structure or type, or any organizational number assigned by its jurisdiction; and (f) all other information set forth on the Perfection Certificate pertaining to Borrower and each of its Subsidiaries is accurate and complete (it being understood and agreed that Borrower may from time to time update certain information in the Perfection Certificate after the Effective Date to the extent permitted by one or more specific provisions in this Agreement). If Borrower is not now a Registered Organization but later becomes one, Borrower shall promptly notify Bank of such occurrence and provide Bank with Borrower’s organizational identification number.

The execution, delivery and performance by Borrower of the Loan Documents to which it is a party have been duly authorized, and do not (i) conflict with any of Borrower’s organizational documents, (ii) contravene, conflict with, constitute a default under or violate any material Requirement of Law, (iii) contravene, conflict or violate any applicable order, writ, judgment, injunction, decree, determination or award of any Governmental Authority by which Borrower or any of its Subsidiaries or any of their property or assets may be bound or affected, (iv) require any action by, filing, registration, or qualification with, or Governmental Approval from, any

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Governmental Authority (except such Governmental Approvals which have already been obtained and are in full force and effect) or (v) constitute an event of default under any material agreement by which Borrower is bound. Borrower is not in default under any agreement to which it is a party or by which it is bound in which the default could reasonably be expected to have a material adverse effect on Borrower’s business.

5.2 Collateral. Borrower has good title to, has rights in, and the power to transfer each item of the Collateral upon which it purports to grant a Lien hereunder, free and clear of any and all Liens except Permitted Liens. Borrower has no deposit accounts other than the deposit accounts with Bank, the deposit accounts, if any described in the Perfection Certificate delivered to Bank in connection herewith, or of which Borrower has given Bank notice and taken such actions as are necessary to give Bank a perfected security interest therein. The Accounts are bona fide, existing obligations of the Account Debtors.

The Collateral is not in the possession of any third party bailee (such as a warehouse) except as otherwise provided in the Perfection Certificate. None of the components of the Collateral shall be maintained at locations other than as provided in the Perfection Certificate or as permitted pursuant to Section 7.2. In the event that Borrower, after the date hereof, intends to store or otherwise deliver any portion of the Collateral to a bailee, then Borrower will first receive the written consent of Bank and such bailee must execute and deliver a bailee agreement in form and substance satisfactory to Bank in its sole discretion.

All Inventory is in all material respects of good and marketable quality, free from material defects, except normal and customary quality issues occurring in the ordinary course of business, in amounts consistent with past practices.

Borrower is the sole owner of the Intellectual Property which it owns or purports to own except for (a) non-exclusive licenses granted to its customers in the ordinary course of business, (b) over-the-counter software that is commercially available to the public, and (c) material Intellectual Property licensed to Borrower and noted on the Perfection Certificate. Each Patent which it owns or purports to own and which is material to Borrower’s business is valid and enforceable, and no part of the Intellectual Property which Borrower owns or purports to own and which is material to Borrower’s business has been judged invalid or unenforceable, in whole or in part, except to the extent in each of the above such invalidity or unenforceability would not have a material adverse effect on Borrower’s business, taken as a whole. To the best of Borrower’s knowledge, no claim has been made that any part of the Intellectual Property violates the rights of any third party except to the extent such claim would not have a material adverse effect on Borrower’s business, taken as a whole.

5.3 Accounts Receivable; Inventory. For any Eligible Account in any Borrowing Base Certificate, all statements made and all unpaid balances appearing in all invoices, instruments and other documents evidencing such Eligible Accounts are and shall be true and correct and all such invoices, instruments and other documents, and all of Borrower’s Books are genuine and in all respects what they purport to be. Whether or not an Event of Default has occurred and is continuing, Bank may, after consultation with Borrower, notify any Account Debtor owing Borrower money of Bank’s security interest in such funds and verify the amount of such Eligible Account. All sales and other transactions underlying or giving rise to each Eligible Account shall comply in all material respects with all applicable laws and governmental rules and regulations. Borrower has no knowledge of any actual or imminent Insolvency Proceeding of any Account Debtor whose accounts are Eligible Accounts in any Borrowing Base Certificate. To the best of Borrower’s knowledge, all signatures and endorsements on all documents, instruments, and agreements relating to all Eligible Accounts are genuine, and all such documents, instruments and agreements are legally enforceable in accordance with their terms.

5.4 Litigation. There are no actions or proceedings pending or, to the knowledge of the Responsible Officers, threatened in writing by or against Borrower or any of its Subsidiaries involving more than, individually or in the aggregate, One Hundred Fifty Thousand Dollars ($150,000).

5.5 Financial Condition. All consolidated financial statements for Borrower delivered to Bank fairly present in all material respects Borrower’s consolidated financial condition and Borrower’s consolidated results of operations. There has not been any material deterioration in Borrower’s consolidated financial condition since the date of the most recent financial statements submitted to Bank.

5.6 Solvency. The fair salable value of Borrower’s assets (including goodwill minus disposition costs) exceeds the fair value of its liabilities; Borrower is not left with unreasonably small capital after the transactions in this Agreement; and Borrower is able to pay its debts (including trade debts) as they mature.

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5.7 Regulatory Compliance. Borrower is not an “investment company” or a company “controlled” by an “investment company” under the Investment Company Act of 1940, as amended. Borrower is not engaged as one of its important activities in extending credit for margin stock (under Regulations X, T and U of the Federal Reserve Board of Governors). Borrower has complied in all material respects with the Federal Fair Labor Standards Act. Neither Borrower nor any of its Subsidiaries is a “holding company” or an “affiliate” of a “holding company” or a “subsidiary company” of a “holding company” as each term is defined and used in the Public Utility Holding Company Act of 2005. Borrower has not violated any laws, ordinances or rules, the violation of which could reasonably be expected to have a material adverse effect on its business. Except as described in the Perfection Certificate or otherwise disclosed to Bank, none of Borrower’s or any of its Subsidiaries’ properties or assets has been used by Borrower or any Subsidiary or, to the best of Borrower’s knowledge, by previous Persons, in disposing, producing, storing, treating, or transporting any hazardous substance other than legally. Borrower and each of its Subsidiaries have obtained all consents, approvals and authorizations of, made all declarations or filings with, and given all notices to, all Governmental Authorities that are necessary to continue their respective businesses as currently conducted, the absence of which could reasonably be expected to have a materially adverse effect on the Borrower.

5.8 Subsidiaries; Investments. Borrower does not own any stock, partnership interest or other equity securities except for Permitted Investments.

5.9 Tax Returns and Payments; Pension Contributions. Borrower has timely filed all required tax returns and reports, and Borrower has timely paid all foreign, federal, state and local taxes, assessments, deposits and contributions owed by Borrower. Borrower may defer payment of any contested taxes, provided that Borrower (a) in good faith contests its obligation to pay the taxes by appropriate proceedings promptly and diligently instituted and conducted, (b) notifies Bank in writing of the commencement of, and any material development in, the proceedings, (c) posts bonds or takes any other steps required to prevent the Governmental Authority levying such contested taxes from obtaining a Lien upon any of the Collateral that is other than a “Permitted Lien”. Borrower is unaware of any claims or adjustments proposed for any of Borrower’s prior tax years which could result in additional taxes becoming due and payable by Borrower. Borrower has paid all amounts necessary to fund all present pension, profit sharing and deferred compensation plans in accordance with their terms, and Borrower has not withdrawn from participation in, and has not permitted partial or complete termination of, or permitted the occurrence of any other event with respect to, any such plan which could reasonably be expected to result in any liability of Borrower, including any liability to the Pension Benefit Guaranty Corporation or its successors or any other governmental agency.

5.10 Use of Proceeds. Borrower shall use the proceeds of the Credit Extensions solely as working capital to fund its general business requirements and not for personal, family, household or agricultural purposes.

5.11 Full Disclosure. No written representation, warranty or other statement of Borrower in any certificate or written statement given to Bank, as of the date such representation, warranty, or other statement was made, taken together with all such written certificates and written statements given to Bank, contains any untrue statement of a material fact or omits to state a material fact necessary to make the statements contained in the certificates or statements not misleading (it being recognized by Bank that the projections and forecasts provided by Borrower in good faith and based upon reasonable assumptions are not viewed as facts and that actual results during the period or periods covered by such projections and forecasts may differ from the projected or forecasted results).

5.12 Definition of “Knowledge.” For purposes of the Loan Documents, whenever a representation or warranty is made to Borrower’s knowledge or awareness, to the “best of” Borrower’s knowledge, or with a similar qualification, knowledge or awareness means the actual knowledge, after reasonable investigation, of the Responsible Officers.

6 AFFIRMATIVE COVENANTS

Borrower shall do all of the following:

6.1 Government Compliance. (a) Maintain its and all its Subsidiaries’ legal existence and good standing in their respective jurisdictions of formation and maintain qualification in each jurisdiction in which the failure to so qualify would reasonably be expected to have a material adverse effect on Borrower’s business or operations. Borrower shall comply, and have each Subsidiary comply, with all laws, ordinances and regulations to which it is subject, the noncompliance with which could have a material adverse effect on Borrower’s business.

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(b) Obtain all of the Governmental Approvals necessary for the performance by Borrower of its obligations under the Loan Documents to which it is a party and the grant of a security interest to Bank in the Collateral. Borrower shall promptly provide copies of any such obtained Governmental Approvals to Bank.

6.2 Financial Statements, Reports, Certificates.

(a) Borrower shall provide Bank with the following:

(i) (A) weekly, and (B) upon each request for a Credit Extension, a Transaction Report;

(ii) within fifteen (15) days after the end of each month in which there are any outstanding Credit Extensions (otherwise quarterly, within fifteen (15) days after the end of each fiscal quarter), (A) accounts receivable agings, aged by invoice date (including, without limitation, accounts receivable agings for accounts receivable used in determining EXIM Loans), (B) accounts payable agings, aged by invoice date, and outstanding or held check registers, if any, (C) reconciliations of accounts receivable agings (aged by invoice date), transaction reports, Deferred Revenue report and general ledger, (D) perpetual inventory reports for Inventory valued on a first-in, first-out basis at the lower of cost or market (in accordance with GAAP) or such other inventory reports as are requested by Bank in its good faith business judgment; and (e) a completed Borrowing Base Certificate;

(iii) as soon as available, and in any event within thirty (30) days after the end of each month, monthly unaudited financial statements;

(iv) within thirty (30) days after the end of each month a monthly Compliance Certificate signed by a Responsible Officer, certifying that as of the end of such month, Borrower was in full compliance with all of the terms and conditions of this Agreement, and setting forth calculations showing compliance with the financial covenants set forth in this Agreement and such other information as Bank shall reasonably request, including, without limitation, a statement that at the end of such month there were no held checks;

(v) within fifteen (15) days after the end of each fiscal quarter, copies of invoices for no less than ten percent (10%) of the outstanding balance of EXIM Bank accounts receivable as of the last day of such fiscal quarter;

(vi) within thirty (30) days prior to the end of each fiscal year of Borrower and as amended or updated, (A) annual operating budgets (including income statements, balance sheets and cash flow statements, by month) for the upcoming fiscal year of Borrower, and (B) annual financial projections for the following fiscal year (on a quarterly basis) as approved by Borrower’s board of directors, together with any related business forecasts used in the preparation of such annual financial projections;

(vii) as soon as available, and in any event within one hundred eighty (180) days following the end of Borrower’s fiscal year, annual financial statements certified by, and with an unqualified opinion of, independent certified public accountants acceptable to Bank; provided, that for Borrower’s fiscal year ended December 31, 2010, such annual financial statements shall be certified by, and with an unqualified opinion of (other than qualified with respect to “going concern”), independent certified public accountants acceptable to Bank

(viii) within five (5) days of delivery, copies of all statements, reports and notices made available to Borrower’s security holders or to any holders of Subordinated Debt;

(ix) a prompt report of any legal actions pending or threatened in writing against Borrower or any of its Subsidiaries that could result in damages or costs to Borrower or any of its Subsidiaries of, individually or in the aggregate, One Hundred Fifty Thousand Dollars ($150,000) or more;

Notwithstanding the foregoing, when Borrower is at or above the Liquidity Threshold, provided no Event of Default has occurred and is continuing, Borrower shall be required to provide Bank with the reports and schedules required pursuant to clause (a)(i)(A) above monthly, within fifteen (15) days after the end of each month.

(b) In the event that Borrower is or becomes subject to the reporting requirements under the Securities Exchange Act of 1934, as amended, within five (5) days after filing, all reports on Form 10-K, 10-Q and 8-K filed with the SEC or a link thereto on Borrower’s or another website on the Internet.

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(c) Borrower shall provide Bank with prompt written notice of Borrower’s knowledge of an event that affects the value of the Intellectual Property and that would have a material adverse effect on Borrower’s business, taken as a whole.

6.3 Accounts Receivable.

(a) Schedules and Documents Relating to Accounts. Borrower shall deliver to Bank transaction reports and schedules of collections, as provided in Section 6.2, on Bank’s standard forms; provided, however, that Borrower’s failure to execute and deliver the same shall not affect or limit Bank’s Lien and other rights in all of Borrower’s Accounts, nor shall Bank’s failure to advance or lend against a specific Account affect or limit Bank’s Lien and other rights therein. If requested by Bank, Borrower shall furnish Bank with copies (or, at Bank’s request after the occurrence and during the continuance of an Event of Default, originals) of all contracts, orders, invoices, and other similar documents, and all shipping instructions, delivery receipts, bills of lading, and other evidence of delivery, for any goods the sale or disposition of which gave rise to such Accounts. In addition, Borrower shall deliver to Bank, on its request, the originals of all instruments, chattel paper, security agreements, guarantees and other documents and property evidencing or securing any Accounts, in the same form as received, with all necessary endorsements, and copies of all credit memos.

(b) Disputes. Borrower shall promptly notify Bank of all disputes or claims relating to Accounts, to the extent such disputes or claims involve amounts in excess of Two Hundred Fifty Thousand Dollars ($250,000) in the aggregate for all Account Debtors. Borrower may forgive (completely or partially), compromise, or settle any Account for less than payment in full, or agree to do any of the foregoing so long as (i) Borrower does so in good faith, in a commercially reasonable manner, in the ordinary course of business, in arm’s-length transactions, and reports the same to Bank in the regular reports provided to Bank; (ii) no Default or Event of Default has occurred and is continuing; and (iii) after taking into account all such discounts, settlements and forgiveness, the total outstanding Advances will not exceed the Availability Amount.

(c) Collection of Accounts. Borrower shall have the right to collect all Accounts, unless and until a Default or an Event of Default has occurred and is continuing. All payments on, and proceeds of, Accounts shall be deposited directly by the applicable Account Debtor into a lockbox account, or such other “blocked account” as Bank may specify, pursuant to a blocked account agreement in form and substance satisfactory to Bank in its sole discretion. Whether or not an Event of Default has occurred and is continuing, Borrower shall immediately deliver all payments on and proceeds of Accounts to an account maintained with Bank to be applied (i) prior to an Event of Default, to the Revolving Line pursuant to the terms of Section 2.5(b) hereof, and (ii) after the occurrence and during the continuance of an Event of Default, pursuant to the terms of Section 9.4 hereof; provided, however, when Borrower is at or above the Liquidity Threshold, such payments and proceeds shall be transferred to an account of Borrower maintained at Bank.

(d) Returns. Provided no Event of Default has occurred and is continuing, if any Account Debtor returns any Inventory having an aggregate value in excess of Two Hundred Fifty Thousand Dollars ($250,000) to Borrower, Borrower shall promptly (i) determine the reason for such return, (ii) issue a credit memorandum to the Account Debtor in the appropriate amount, and (iii) provide a copy of such credit memorandum to Bank, upon request from Bank. In the event any attempted return occurs after the occurrence and during the continuance of any Event of Default, Borrower shall immediately notify Bank of the return of the Inventory.

(e) Verification. Bank may, from time to time, after consultation with Borrower, verify directly with the respective Account Debtors the validity, amount and other matters relating to the Accounts, either in the name of Borrower or Bank or such other name as Bank may choose.

(f) No Liability. Bank shall not be responsible or liable for any shortage or discrepancy in, damage to, or loss or destruction of, any goods, the sale or other disposition of which gives rise to an Account, or for any error, act, omission, or delay of any kind occurring in the settlement, failure to settle, collection or failure to collect any Account, or for settling any Account in good faith for less than the full amount thereof, nor shall Bank be deemed to be responsible for any of Borrower’s obligations under any contract or agreement giving rise to an Account. Nothing herein shall, however, relieve Bank from liability for its own gross negligence or willful misconduct.

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6.4 Remittance of Proceeds. Except as otherwise provided in Section 6.3(c), deliver, in kind, all proceeds arising from the disposition of any Collateral to Bank in the original form in which received by Borrower not later than the following Business Day after receipt by Borrower, to be applied to the Obligations (1) prior to an Event of Default, pursuant to the terms of Section 2.5(b) hereof, and (2) after the occurrence and during the continuance of an Event of Default, pursuant to the terms of Section 9.4 hereof; provided that, if no Event of Default has occurred and is continuing, Borrower shall not be obligated to remit to Bank the proceeds of the sale of surplus, worn out or obsolete Equipment disposed of by Borrower in good faith in an arm’s length transaction for an aggregate purchase price of Five Hundred Thousand Dollars ($500,000) or less (for all such transactions in any fiscal year). Borrower agrees that it will maintain all proceeds of Collateral in an account maintained with Bank. Nothing in this Section limits the restrictions on disposition of Collateral set forth elsewhere in this Agreement.

6.5 Taxes; Pensions; Withholding. Timely file, and require each of its Subsidiaries to timely file, all required tax returns and reports and timely pay, and require each of its Subsidiaries to timely pay, all foreign, federal, state and local taxes, assessments, deposits and contributions owed by Borrower and each of its Subsidiaries, except for deferred payment of any taxes contested pursuant to the terms of Section 5.9 hereof, and shall deliver to Bank, on demand, appropriate certificates attesting to such payments, and pay all amounts necessary to fund all present pension, profit sharing and deferred compensation plans in accordance with their terms.

6.6 Access to Collateral; Books and Records. In addition to the Initial Audit, at reasonable times, on one (1) Business Day’s notice (provided no notice is required if an Event of Default has occurred and is continuing), Bank, or its agents, shall have the right, up to two (2) times per year (or more frequently (i) after the occurrence and during the continuance of an Event of Default, as Bank shall determine necessary, or (ii) at the direction of EXIM Bank), to inspect the Collateral and the right to audit and copy Borrower’s Books. The foregoing inspections and audits shall be at Borrower’s expense, and the charge therefor shall be $850 per person per day (or such higher amount as shall represent Bank’s then-current standard charge for the same), plus reasonable out-of-pocket expenses. In the event Borrower and Bank schedule an audit more than ten (10) days in advance, and Borrower cancels or seeks to reschedule the audit with less than ten (10) days written notice to Bank, then (without limiting any of Bank’s rights or remedies), Borrower shall pay Bank a fee of $1,000 plus any out-of-pocket expenses incurred by Bank to compensate Bank for the anticipated costs and expenses of the cancellation or rescheduling.

6.7 Insurance. Keep its business and the Collateral insured for risks and in amounts standard for companies in Borrower’s industry and location and as Bank may reasonably request. Insurance policies shall be in a form, with companies, and in amounts that are satisfactory to Bank. All property policies shall have a lender’s loss payable endorsement showing Bank as an additional lender loss payee and waive subrogation against Bank. All liability policies shall show, or have endorsements showing, Bank as an additional insured. All policies (or their respective endorsements) shall provide that the insurer shall give Bank at least twenty (20) days notice before canceling, amending, or declining to renew its policy. At Bank’s request, Borrower shall deliver certified copies of policies and evidence of all premium payments. Proceeds payable under any policy shall, at Bank’s option, be payable to Bank on account of the Obligations. Notwithstanding the foregoing, (a) so long as no Event of Default has occurred and is continuing, Borrower shall have the option of applying the proceeds of any casualty policy up to Two Hundred Fifty Thousand Dollars ($250,000) with respect to any loss, but not exceeding Five Hundred Thousand Dollars ($500,000) in the aggregate for all losses under all casualty policies in any one year, toward the replacement or repair of destroyed or damaged property; provided that any such replaced or repaired property (i) shall be of equal or like value as the replaced or repaired Collateral and (ii) shall be deemed Collateral in which Bank has been granted a first priority security interest, and (b) after the occurrence and during the continuance of an Event of Default, all proceeds payable under such casualty policy shall, at the option of Bank, be payable to Bank on account of the Obligations. If Borrower fails to obtain insurance as required under this Section 6.7 or to pay any amount or furnish any required proof of payment to third persons and Bank, Bank may make all or part of such payment or obtain such insurance policies required in this Section 6.7, and take any action under the policies Bank deems prudent.

6.8 Operating Accounts.

(a) Maintain all of its and its Subsidiaries’, if any, depository, operating accounts and securities accounts with Bank and Bank’s Affiliates with all excess funds maintained at or invested through Bank or an affiliate of Bank; provided, however, Aspen GmbH may maintain depository, operating accounts and securities accounts in a financial institution located in the Federal Republic of Germany (the “German Accounts”), in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000) at any time; provided further, that Borrower shall have up to sixty (60) days to provide Bank evidence satisfactory to Bank, in its sole discretion, that, during such sixty (60) day period (the “Account Transition Period”), Borrower has transitioned all of its and its Subsidiaries existing depository, operating accounts and securities accounts maintained at financial institutions other than Bank or Bank’s Affiliates (other than the German Accounts) to accounts with Bank or Bank’s Affiliates.

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(b) Provide Bank five (5) days prior-written notice before establishing any Collateral Account at or with any bank or financial institution other than Bank or Bank’s Affiliates. For each Collateral Account that Borrower at any time maintains, Borrower shall cause the applicable bank or financial institution (other than Bank) at or with which any Collateral Account is maintained to execute and deliver a Control Agreement or other appropriate instrument with respect to such Collateral Account to perfect Bank’s Lien in such Collateral Account in accordance with the terms hereunder which Control Agreement may not be terminated without the prior written consent of Bank. The provisions of the previous sentence shall not apply to the German accounts or to deposit accounts exclusively used for payroll, payroll taxes and other employee wage and benefit payments to or for the benefit of Borrower’s employees and identified to Bank by Borrower as such.

6.9 Financial Covenants.

Maintain at all times, to be certified by Borrower as of the last day of each month, unless otherwise noted, on a consolidated basis with respect to Borrower and its Subsidiaries, unless otherwise noted:

(a) Liquidity. Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).

(b) Tangible Net Worth. A Tangible Net Worth of at least Forty Million Dollars ($40,000,000).

6.10 Protection of Intellectual Property Rights. (i) Protect, defend and maintain the validity and enforceability of its material Intellectual Property; (ii) promptly advise Bank in writing of material infringements of its Intellectual Property; and (iii) not allow any Intellectual Property material to Borrower’s business to be abandoned, forfeited or dedicated to the public without Bank’s written consent, other than where any of the foregoing would not have a material adverse effect on Borrower’s business, taken as a whole.

6.11 Litigation Cooperation. From the date hereof and continuing through the termination of this Agreement, make available to Bank, without expense to Bank, Borrower and its officers, employees and agents and Borrower’s Books, to the extent that Bank may deem them reasonably necessary to prosecute or defend any third-party suit or proceeding instituted by or against Bank with respect to any Collateral or relating to Borrower.

6.12 Creation/Acquisition of Subsidiaries. Notwithstanding and without limiting the negative covenant contained in Section 7.3 hereof, in the event Borrower or any Subsidiary creates or acquires any Subsidiary, Borrower and such Subsidiary shall promptly notify Bank of the creation or acquisition of such new Subsidiary and, at Bank’s request, in its sole discretion, take all such action as may be reasonably required by Bank to cause each such Subsidiary to, in Bank’s sole discretion, become a co-Borrower or Guarantor under the Loan Documents and grant a continuing pledge and security interest in and to the assets of such Subsidiary (substantially as described on Exhibit A hereto); and Borrower shall grant and pledge to Bank a perfected security interest in the stock, units or other evidence of ownership of each Subsidiary.

6.13 Further Assurances. Execute any further instruments and take further action as Bank reasonably requests to perfect or continue Bank’s Lien in the Collateral or to effect the purposes of this Agreement. Borrower shall deliver to Bank, within five (5) days after the same are sent or received, copies of all correspondence, reports, documents and other filings with any Governmental Authority regarding compliance with or maintenance of Governmental Approvals or Requirements of Law or that could reasonably be expected to have a material effect on any of the Governmental Approvals or otherwise on the operations of Borrower or any of its Subsidiaries.

7 NEGATIVE COVENANTS

Borrower shall not do any of the following without Bank’s prior written consent:

7.1 Dispositions. Convey, sell, lease, transfer, assign, or otherwise dispose of (collectively, “Transfer”), or permit any of its Subsidiaries to Transfer, all or any part of its business or property, except for Transfers (a) of Inventory in the ordinary course of business; (b) of worn out or obsolete Equipment; (c) in connection with Permitted Liens and Permitted Investments; and (d) of non-exclusive licenses for the use of the property of Borrower or its Subsidiaries in the ordinary course of business and licenses that could not result in a legal transfer of title of the licensed property but that may be exclusive in respects other than territory and that may be exclusive as to territory only as to discreet geographical areas outside of the United States.

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7.2 Changes in Business, Management, Ownership or Business Locations. (a) Engage in or permit any of its Subsidiaries, if any, to engage in any business other than the businesses currently engaged in by Borrower and such Subsidiary, as applicable, or reasonably related thereto; (b) liquidate or dissolve; or (c) (i) any Key Person ceases to hold such office(s) with Borrower and replacement(s) satisfactory to Bank are not made within one hundred twenty (120) days after such Key Person’s departure from Borrower; or (ii) enter into any transaction or series of related transactions in which the stockholders of Borrower who were not stockholders immediately prior to the first such transaction own more than forty percent (40%) of the voting stock of Borrower immediately after giving effect to such transaction or related series of such transactions (other than by the sale of Borrower’s equity securities in a public offering or to venture capital investors so long as Borrower identifies to Bank the venture capital investors prior to the closing of the transaction and provides to Bank a description of the material terms of the transaction).

Borrower shall not, without at least thirty (30) days prior written notice to Bank: (1) add any new offices or business locations, including warehouses (unless such new offices or business locations contain less than Fifty Thousand Dollars ($50,000) in Borrower’s assets or property) or deliver any portion of the Collateral valued, individually or in the aggregate, in excess of Fifty Thousand Dollars ($50,000) to a bailee at a location other than to a bailee and at a location already disclosed in the Perfection Certificate, (2) change its jurisdiction of organization, (3) change its organizational structure or type, (4) change its legal name, or (5) change any organizational number (if any) assigned by its jurisdiction of organization. If Borrower intends to deliver any portion of the Collateral valued, individually or in the aggregate, in excess of Fifty Thousand Dollars ($50,000) to a bailee, and Bank and such bailee are not already parties to a bailee agreement governing both the Collateral and the location to which Borrower intends to deliver the Collateral, then Borrower will first receive the written consent of Bank, and such bailee shall execute and deliver a bailee agreement in form and substance satisfactory to Bank in its sole discretion.

7.3 Mergers or Acquisitions. Merge or consolidate, or permit any of its Subsidiaries to merge or consolidate, with any other Person, or acquire, or permit any of its Subsidiaries to acquire, all or substantially all of the capital stock or property of another Person. A Subsidiary may merge or consolidate into another Subsidiary or into Borrower.

7.4 Indebtedness. Create, incur, assume, or be liable for any Indebtedness, or permit any Subsidiary to do so, other than Permitted Indebtedness.

7.5 Encumbrance. Create, incur, allow, or suffer any Lien (other than Permitted Liens) on any of its property, or assign or convey any right to receive income, including the sale of any Accounts, or permit any of its Subsidiaries to do so, except for Permitted Liens. Borrower shall not permit any Collateral to be subject to any Liens other than the first priority security interest granted herein or Permitted Liens, or enter into any agreement, document, instrument or other arrangement (except with or in favor of Bank except as otherwise permitted herein) with any Person which directly or indirectly prohibits or has the effect of prohibiting Borrower or any Subsidiary from assigning, mortgaging, pledging, granting a security interest in or upon, or encumbering any of Borrower’s or any Subsidiary’s Intellectual Property, except as is otherwise described in the Perfection Certificate, permitted in Section 7.1 hereof and in the definition of “Permitted Liens” herein.

7.6 Maintenance of Collateral Accounts. Maintain any Collateral Account except pursuant to the terms of Section 6.8(b) hereof.

7.7 Distributions; Investments. (a) Pay any dividends or make any distribution or payment or redeem, retire or purchase any capital stock; or (b) directly or indirectly make any Investment (including, without limitation, any additional Investment in any Subsidiary) other than Permitted Investments, or permit any of its Subsidiaries to do so.

7.8 Transactions with Affiliates. Directly or indirectly enter into or permit to exist any material transaction with any Affiliate of Borrower, except for transactions that are in the ordinary course of Borrower’s business, upon fair and reasonable terms that are no less favorable to Borrower than would be obtained in an arm’s length transaction with a non-affiliated Person.

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7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject.

7.10 Compliance. Become an “investment company” or a company controlled by an “investment company”, under the Investment Company Act of 1940, as amended, or undertake as one of its important activities extending credit to purchase or carry margin stock (as defined in Regulation U of the Board of Governors of the Federal Reserve System), or use the proceeds of any Credit Extension for that purpose; fail to meet the minimum funding requirements of ERISA, permit a Reportable Event or non-exempt Prohibited Transaction, as defined in ERISA, to occur; fail to comply with the Federal Fair Labor Standards Act or violate any other law or regulation, if the violation could reasonably be expected to have a material adverse effect on Borrower’s business, or permit any of its Subsidiaries to do so; withdraw or permit any Subsidiary to withdraw from participation in, permit partial or complete termination of, or permit the occurrence of any other event with respect to, any present pension, profit sharing and deferred compensation plan which could reasonably be expected to result in any liability of Borrower, including any liability to the Pension Benefit Guaranty Corporation or its successors or any other governmental agency.

8 EVENTS OF DEFAULT

Any one of the following shall constitute an event of default (an “Event of Default”) under this Agreement:

8.1 Payment Default. Borrower fails to (a) make any payment of principal or interest on any Credit Extension on its due date, or (b) pay any other Obligations within three (3) Business Days after such Obligations are due and payable (which three (3) Business Day cure period shall not apply to payments due on the Revolving Line Maturity Date). During the cure period, the failure to make or pay any payment specified under clause (a) or (b) hereunder is not an Event of Default (but no Credit Extension will be made during the cure period);

8.2 Covenant Default.

(a) Borrower fails or neglects to perform any obligation in Sections 6.2 (provided, however, Borrower shall have five (5) Business Days from the scheduled due date to cure any default under clauses 6.2(a) (ii)-(vi) and clause 6.2(a)(viii)), 6.4, 6.6, 6.7, 6.8, or 6.9, or violates any covenant in Section 7; or

(b) Borrower fails or neglects to perform, keep, or observe any other term, provision, condition, covenant or agreement contained in this Agreement or any Loan Documents, and as to any default (other than those specified in this Section 8) under such other term, provision, condition, covenant or agreement that can be cured, has failed to cure the default within ten (10) days after the occurrence thereof; provided, however, that if the default cannot by its nature be cured within the ten (10) day period or cannot after diligent attempts by Borrower be cured within such ten (10) day period, and such default is likely to be cured within a reasonable time, then Borrower shall have an additional period (which shall not in any case exceed thirty (30) days) to attempt to cure such default, and within such reasonable time period the failure to cure the default shall not be deemed an Event of Default (but no Credit Extensions shall be made during such cure period). Cure periods provided under this section shall not apply, among other things, to financial covenants or any other covenants set forth in clause (a) above;

8.3 Material Adverse Change. A Material Adverse Change occurs;

8.4 Attachment; Levy; Restraint on Business.

(a) (i) The service of process seeking to attach, by trustee or similar process, any funds of Borrower or of any entity under the control of Borrower (including a Subsidiary) on deposit or otherwise maintained with Bank or any Bank Affiliate, or (ii) a notice of lien or levy is filed against any of Borrower’s assets by any government agency, and the same under subclauses (i) and (ii) hereof are not, within ten (10) days after the occurrence thereof, discharged or stayed (whether through the posting of a bond or otherwise); provided, however, no Credit Extensions shall be made during any ten (10) day cure period; or

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(b) (i) any material portion of Borrower’s assets is attached, seized, levied on, or comes into possession of a trustee or receiver, or (ii) any court order enjoins, restrains, or prevents Borrower from conducting any material part of its business;

8.5 Insolvency. (a) Borrower is unable to pay its debts (including trade debts) as they become due or otherwise becomes insolvent; (b) Borrower begins an Insolvency Proceeding; or (c) an Insolvency Proceeding is begun against Borrower and not dismissed or stayed within thirty (30) days (but no Credit Extensions shall be made while of any of the conditions described in clause (a) exist and/or until any Insolvency Proceeding is dismissed);

8.6 Other Agreements. There is, under any agreement to which Borrower or any Guarantor is a party with a third party or parties, (a) any default resulting in a right by such third party or parties, whether or not exercised, to accelerate the maturity of any Indebtedness in an amount individually or in the aggregate in excess of One Hundred Thousand Dollars ($100,000); or (b) any default by Borrower or Guarantor, the result of which could have a material adverse effect on Borrower’s or any Guarantor’s business, taken as a whole;

8.7 Judgments. One or more final judgments, orders, or decrees for the payment of money in an amount, individually or in the aggregate, of at least One Hundred Thousand Dollars ($100,000) (not covered by independent third-party insurance as to which liability has been accepted by such insurance carrier) shall be rendered against Borrower and the same are not, within ten (10) days after the entry thereof, discharged or execution thereof stayed or bonded pending appeal, or such judgments are not discharged prior to the expiration of any such stay (provided that no Credit Extensions will be made prior to the discharge, stay, or bonding of such judgment, order, or decree);

8.8 Misrepresentations. Borrower or any Person acting for Borrower makes any representation, warranty, or other statement now or later in this Agreement, any Loan Document or in any writing delivered to Bank or to induce Bank to enter this Agreement or any Loan Document, and such representation, warranty, or other statement is incorrect in any material respect when made;

8.9 Subordinated Debt. Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement or the PJC Intercreditor Agreement.

8.10 Guaranty. (a) Any guaranty of any Obligations terminates or ceases for any reason to be in full force and effect which could reasonably be expected to have a material adverse effect on the ability of the Borrower and its Subsidiaries, taken as a whole, to repay the Obligations; (b) any Guarantor does not perform any obligation or covenant under any guaranty of the Obligations which could reasonably be expected to have a material adverse effect on the ability of the Borrower and its Subsidiaries, taken as a whole, to repay the Obligations; (c) any circumstance described in Sections 8.3, 8.4, 8.5, 8.7, or 8.8. occurs with respect to any Guarantor which could reasonably be expected to have a material adverse effect on the ability of the Borrower and its Subsidiaries, taken as a whole, to repay the Obligations; (d) the liquidation, winding up, or termination of existence of any Guarantor which could reasonably be expected to have a material adverse effect on the ability of the Borrower and its Subsidiaries, taken as a whole, to repay the Obligations; or (e) (i) a material impairment in the perfection or priority of Bank’s Lien in the collateral provided by Guarantor or in the value of such collateral or (ii) a material adverse change in the general affairs, management, results of operation, condition (financial or otherwise) or the prospect of repayment of the Obligations occurs with respect to any Guarantor and such material impairment or material adverse change could reasonably be expected to have a material adverse effect on the ability of the Borrower and its Subsidiaries, taken as a whole, to repay the Obligations;

8.11 EXIM Guarantee. If the EXIM Guarantee ceases for any reason to be in full force and effect, other than for payment-in-full and termination of the Export-Import Agreement, or if the EXIM Bank declares the EXIM Guarantee void or revokes any obligations under the EXIM Guarantee;

8.12 Export-Import Agreement Default. After the effective date of the Export-Import Agreement, the occurrence of an Event of Default under the Export-Import Agreement or the other EXIM Loan Documents; and

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8.13 Governmental Approvals. Any Governmental Approval shall have been (a) revoked, rescinded, suspended, modified in an adverse manner or not renewed in the ordinary course for a full term or (b) subject to any decision by a Governmental Authority that designates a hearing with respect to any applications for renewal of any of such Governmental Approval or that could result in the Governmental Authority taking any of the actions described in clause (a) above, and such decision or such revocation, rescission, suspension, modification or non-renewal (i) has, or could reasonably be expected to have, a Material Adverse Change, or (ii) adversely affects the legal qualifications of Borrower or any of its Subsidiaries to hold such Governmental Approval in any applicable jurisdiction and such revocation, rescission, suspension, modification or non-renewal could reasonably be expected to affect the status of or legal qualifications of Borrower or any of its Subsidiaries to hold any Governmental Approval in any other jurisdiction.

9 BANK’S RIGHTS AND REMEDIES

9.1 Rights and Remedies. While an Event of Default occurs and continues Bank may, without notice or demand, do any or all of the following:

(a) declare all Obligations immediately due and payable (but if an Event of Default described in Section 8.5 occurs all Obligations are immediately due and payable without any action by Bank);

(b) stop advancing money or extending credit for Borrower’s benefit under this Agreement or under any other agreement between Borrower and Bank;

(c) demand that Borrower (i) deposit cash with Bank in an amount equal to 105% of the Dollar Equivalent of the aggregate face amount of all Letters of Credit remaining undrawn plus all interest, fees, and costs due or to become due in connection therewith (as estimated by Bank in its good faith business judgment), to secure all of the Obligations relating to such Letters of Credit, as collateral security for the repayment of any future drawings under such Letters of Credit, and Borrower shall forthwith deposit and pay such amounts, and (ii) pay in advance all letter of credit fees scheduled to be paid or payable over the remaining term of any Letters of Credit; provided, however, if an Event of Default described in Section 8.5 occurs, the obligation of Borrower to cash collateralize all Letters of Credit remaining undrawn shall automatically become effective without any action by Bank;

(d) terminate any FX Forward Contracts;

(e) settle or adjust disputes and claims directly with Account Debtors for amounts on terms and in any order that Bank considers advisable, notify any Person owing Borrower money of Bank’s security interest in such funds, and verify the amount of such account;

(f) make any payments and do any acts it considers necessary or reasonable to protect the Collateral and/or its security interest in the Collateral. Borrower shall assemble the Collateral if Bank requests and make it available as Bank designates. Bank may enter premises where the Collateral is located, take and maintain possession of any part of the Collateral, and pay, purchase, contest, or compromise any Lien which appears to be prior or superior to its security interest and pay all expenses incurred. Borrower grants Bank a license to enter and occupy any of its premises, without charge, to exercise any of Bank’s rights or remedies;

(g) apply to the Obligations any (i) balances and deposits of Borrower it holds, or (ii) any amount held by Bank owing to or for the credit or the account of Borrower;

(h) ship, reclaim, recover, store, finish, maintain, repair, prepare for sale, advertise for sale, and sell the Collateral. Bank is hereby granted a non-exclusive, royalty-free license or other right to use, without charge, Borrower’s labels, Patents, Copyrights, mask works, rights of use of any name, trade secrets, trade names, Trademarks, and advertising matter, or any similar property as it pertains to the Collateral, in completing production of, advertising for sale, and selling any Collateral and, in connection with Bank’s exercise of its rights under this Section, Borrower’s rights under all licenses and all franchise agreements inure to Bank’s benefit;

(i) place a “hold” on any account maintained with Bank and/or deliver a notice of exclusive control, any entitlement order, or other directions or instructions pursuant to any Control Agreement or similar agreements providing control of any Collateral;

(j) demand and receive possession of Borrower’s Books; and

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(k) exercise all rights and remedies available to Bank under the Loan Documents or at law or equity, including all remedies provided under the Code (including disposal of the Collateral pursuant to the terms thereof).

9.2 Power of Attorney. Borrower hereby irrevocably appoints Bank as its lawful attorney-in-fact, exercisable upon the occurrence and during the continuance of an Event of Default, to: (a) endorse Borrower’s name on any checks or other forms of payment or security; (b) sign Borrower’s name on any invoice or bill of lading for any Account or drafts against Account Debtors; (c) settle and adjust disputes and claims about the Accounts directly with Account Debtors, for amounts and on terms Bank determines reasonable; (d) make, settle, and adjust all claims under Borrower’s insurance policies; (e) pay, contest or settle any Lien, charge, encumbrance, security interest, and adverse claim in or to the Collateral, or any judgment based thereon, or otherwise take any action to terminate or discharge the same; and (f) transfer the Collateral into the name of Bank or a third party as the Code permits. Borrower hereby appoints Bank as its lawful attorney-in-fact to sign Borrower’s name on any documents necessary to perfect or continue the perfection of Bank’s security interest in the Collateral regardless of whether an Event of Default has occurred until all Obligations have been satisfied in full and Bank is under no further obligation to make Credit Extensions hereunder. Bank’s foregoing appointment as Borrower’s attorney in fact, and all of Bank’s rights and powers, being coupled with an interest, are irrevocable until all Obligations have been fully repaid and performed and Bank’s obligation to provide Credit Extensions terminates.

9.3 Protective Payments. If Borrower fails to obtain the insurance called for by Section 6.7 or fails to pay any premium thereon or fails to pay any other amount which Borrower is obligated to pay under this Agreement or any other Loan Document, Bank may obtain such insurance or make such payment, and all amounts so paid by Bank are Bank Expenses and immediately due and payable, bearing interest at the then highest rate applicable to the Obligations, and secured by the Collateral. Bank will make reasonable efforts to provide Borrower with notice of Bank obtaining such insurance at the time it is obtained or within a reasonable time thereafter. No payments by Bank are deemed an agreement to make similar payments in the future or Bank’s waiver of any Event of Default.

9.4 Application of Payments and Proceeds. If an Event of Default has occurred and is continuing, Bank may apply any funds in its possession, whether from Borrower account balances, payments, proceeds realized as the result of any collection of Accounts or other disposition of the Collateral, or otherwise, to the Obligations in such order as Bank shall determine in its sole discretion. Any surplus shall be paid to Borrower or to other Persons legally entitled thereto; Borrower shall remain liable to Bank for any deficiency. If Bank, in its good faith business judgment, directly or indirectly enters into a deferred payment or other credit transaction with any purchaser at any sale of Collateral, Bank shall have the option, exercisable at any time, of either reducing the Obligations by the principal amount of the purchase price or deferring the reduction of the Obligations until the actual receipt by Bank of cash therefor.

9.5 Bank’s Liability for Collateral. So long as Bank complies with reasonable banking practices regarding the safekeeping of the Collateral in the possession or under the control of Bank, Bank shall not be liable or responsible for: (a) the safekeeping of the Collateral; (b) any loss or damage to the Collateral; (c) any diminution in the value of the Collateral; or (d) any act or default of any carrier, warehouseman, bailee, or other Person. Borrower bears all risk of loss, damage or destruction of the Collateral.

9.6 No Waiver; Remedies Cumulative. Bank’s failure, at any time or times, to require strict performance by Borrower of any provision of this Agreement or any other Loan Document shall not waive, affect, or diminish any right of Bank thereafter to demand strict performance and compliance herewith or therewith. No waiver hereunder shall be effective unless signed by the party granting the waiver and then is only effective for the specific instance and purpose for which it is given. Bank’s rights and remedies under this Agreement and the other Loan Documents are cumulative. Bank has all rights and remedies provided under the Code, by law, or in equity. Bank’s exercise of one right or remedy is not an election and shall not preclude Bank from exercising any other remedy under this Agreement or other remedy available at law or in equity, and Bank’s waiver of any Event of Default is not a continuing waiver. Bank’s delay in exercising any remedy is not a waiver, election, or acquiescence.

9.7 Demand Waiver. Borrower waives demand, notice of default or dishonor, notice of payment and nonpayment, notice of any default, nonpayment at maturity, release, compromise, settlement, extension, or renewal of accounts, documents, instruments, chattel paper, and guarantees held by Bank on which Borrower is liable.

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10 NOTICES

All notices, consents, requests, approvals, demands, or other communication (collectively, “Communication”), other than Advance requests made pursuant to Section 3.4, by any party to this Agreement or any other Loan Document must be in writing and be delivered or sent by facsimile at the addresses or facsimile numbers listed below. Bank or Borrower may change its notice address by giving the other party written notice thereof. Each such Communication shall be deemed to have been validly served, given, or delivered: (a) upon the earlier of actual receipt and three (3) Business Days after deposit in the U.S. mail, registered or certified mail, return receipt requested, with proper postage prepaid; (b) upon transmission, when sent by facsimile transmission (with such facsimile promptly confirmed by delivery of a copy by personal delivery or United States mail as otherwise provided in this Section 10); (c) one (1) Business Day after deposit with a reputable overnight courier with all charges prepaid; or (d) when delivered, if hand-delivered by messenger, all of which shall be addressed to the party to be notified and sent to the address or facsimile number indicated below. Advance requests made pursuant to Section 3.4 must be in writing and may be in the form of electronic mail, delivered to Bank by Borrower at the e-mail address of Bank provided below and shall be deemed to have been validly served, given, or delivered when sent (with such electronic mail promptly confirmed by delivery of a copy by personal delivery or United States mail as otherwise provided in this Section 10). Bank or Borrower may change its address, facsimile number, or electronic mail address by giving the other party written notice thereof in accordance with the terms of this Section 10.

If to Borrower:	Aspen Aerogels, Inc. 30 Forbes Road, Building B Northborough, Massachusetts 01532 Attn: John Fairbanks Fax: (508) 691-1200 Email: jfairbanks@aerogel.com
with a copy to:	Edwards Angell Palmer & Dodge LLP 111 Huntington Ave Boston, MA 02199 Attn: Christopher W. Nelson Fax: (888) 325.9513 Email: cnelson@eapdlaw.com
If to Bank:	Silicon Valley Bank 275 Grove Street, Suite 2-200 Newton, Massachusetts 02466 Attn: Mr. Dave Rodriguez Fax: (617) 969-4395 Email: drodriguez@svb.com
with a copy to:	Riemer & Braunstein LLP Three Center Plaza Boston, Massachusetts 02108 Attn: Charles W. Stavros, Esquire Fax: (617) 880-3456 Email: cstavros@riemerlaw.com

11 CHOICE OF LAW, VENUE AND JURY TRIAL WAIVER

Massachusetts law governs the Loan Documents without regard to principles of conflicts of law. Borrower and Bank each submit to the exclusive jurisdiction of the State and Federal courts in Massachusetts; provided, however, that nothing in this Agreement shall be deemed to operate to preclude Bank from bringing suit or taking other legal action in any other jurisdiction to realize on the Collateral or any other security for the Obligations, or to enforce a judgment or other court order in favor of Bank. Borrower expressly submits and consents in advance to such jurisdiction in any action or suit commenced in any such court, and Borrower hereby waives any objection that it may have based upon lack of personal jurisdiction, improper venue, or forum non conveniens and hereby consents to the granting of such legal or equitable relief as is deemed appropriate by such

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court. Borrower hereby waives personal service of the summons, complaints, and other process issued in such action or suit and agrees that service of such summons, complaints, and other process may be made by registered or certified mail addressed to Borrower at the address set forth in Section 10 of this Agreement and that service so made shall be deemed completed upon the earlier to occur of Borrower’s actual receipt thereof or three (3) days after deposit in the U.S. mails, proper postage prepaid. NOTWITHSTANDING ANYTHING TO THE CONTRARY SET FORTH HEREINABOVE, BANK SHALL SPECIFICALLY HAVE THE RIGHT TO BRING ANY ACTION OR PROCEEDING AGAINST BORROWER OR ITS PROPERTY IN THE COURTS OF ANY OTHER JURISDICTION WHICH BANK DEEMS NECESSARY OR APPROPRIATE IN ORDER TO REALIZE ON THE COLLATERAL OR TO OTHERWISE ENFORCE BANK’S RIGHTS AGAINST BORROWER OR ITS PROPERTY.

TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, BORROWER AND BANK EACH WAIVE THEIR RIGHT TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION ARISING OUT OF OR BASED UPON THIS AGREEMENT, THE LOAN DOCUMENTS OR ANY CONTEMPLATED TRANSACTION, INCLUDING CONTRACT, TORT, BREACH OF DUTY AND ALL OTHER CLAIMS. THIS WAIVER IS A MATERIAL INDUCEMENT FOR BOTH PARTIES TO ENTER INTO THIS AGREEMENT. EACH PARTY HAS REVIEWED THIS WAIVER WITH ITS COUNSEL.

12 GENERAL PROVISIONS

12.1 Termination Prior to Maturity Date. This Agreement may be terminated prior to the Revolving Line Maturity Date by Borrower, effective three (3) Business Days after written notice of termination is given to Bank or if Bank’s obligation to fund Credit Extensions terminates pursuant to the terms of Section 2.1.1(b). Notwithstanding any such termination, Bank’s lien and security interest in the Collateral shall continue until Borrower fully satisfies its Obligations. Upon payment in full of the Obligations and at such time as Bank’s obligation to make Credit Extensions has terminated, Bank shall release its liens and security interests in the Collateral and all rights therein shall revert to Borrower.

12.2 Successors and Assigns. This Agreement binds and is for the benefit of the successors and permitted assigns of each party. Borrower may not assign this Agreement or any rights or obligations under it without Bank’s prior written consent (which may be granted or withheld in Bank’s discretion). Bank has the right, without the consent of or notice to Borrower, to sell, transfer, assign, negotiate, or grant participation in all or any part of, or any interest in, Bank’s obligations, rights, and benefits under this Agreement and the other Loan Documents; provided, that, prior to the occurrence and during the continuance of an Event of Default, any such sale, transfer, assignment, negotiation or grant of a participation to a Person or entity other than an institutional lender shall require Borrower’s prior written consent, such consent not to be unreasonably withheld.

12.3 Indemnification. Borrower agrees to indemnify, defend and hold Bank and its directors, officers, employees, agents, attorneys, or any other Person affiliated with or representing Bank (each, an “Indemnified Person”) harmless against: (a) all obligations, demands, claims, and liabilities (collectively, “Claims”) claimed or asserted by any other party in connection with the transactions contemplated by the Loan Documents; and (b) all losses or expenses (including Bank Expenses) in any way suffered, incurred, or paid by such Indemnified Person as a result of, following from, consequential to, or arising from transactions between Bank and Borrower contemplated by the Loan Documents (including reasonable attorneys’ fees and expenses), except for Claims and/or losses directly caused by such Indemnified Person’s gross negligence or willful misconduct.

12.4 Time of Essence. Time is of the essence for the performance of all Obligations in this Agreement.

12.5 Correction of Loan Documents. Bank may correct patent errors and fill in any blanks in the Loan Documents consistent with the agreement of the parties.

12.6 Severability of Provisions. Each provision of this Agreement is severable from every other provision in determining the enforceability of any provision.

12.7 Amendments in Writing; Waiver; Integration. No purported amendment or modification of any Loan Document, or waiver, discharge or termination of any obligation under any Loan Document, shall be enforceable or admissible unless, and only to the extent, expressly set forth in a writing signed by the party against which enforcement or admission is sought. Without limiting the generality of the foregoing, no oral promise or

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statement, nor any action, inaction, delay, failure to require performance or course of conduct shall operate as, or evidence, an amendment, supplement or waiver or have any other effect on any Loan Document. Any waiver granted shall be limited to the specific circumstance expressly described in it, and shall not apply to any subsequent or other circumstance, whether similar or dissimilar, or give rise to, or evidence, any obligation or commitment to grant any further waiver. The Loan Documents represent the entire agreement about this subject matter and supersede prior negotiations or agreements. All prior agreements, understandings, representations, warranties, and negotiations between the parties about the subject matter of the Loan Documents merge into the Loan Documents.

12.8 Counterparts. This Agreement may be executed in any number of counterparts and by different parties on separate counterparts, each of which, when executed and delivered, is an original, and all taken together, constitute one Agreement.

12.9 Survival. All covenants, representations and warranties made in this Agreement continue in full force until this Agreement has terminated pursuant to its terms and all Obligations (other than inchoate indemnity obligations and any other obligations which, by their terms, are to survive the termination of this Agreement) have been paid in full and satisfied. The obligation of Borrower in Section 12.3 to indemnify Bank shall survive until the statute of limitations with respect to such claim or cause of action shall have run.

12.10 Confidentiality. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates (such Subsidiaries and Affiliates, together with Bank, collectively, “Bank Entities”); (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) disclosed to Bank by a third party if Bank does not know that the third party is prohibited from disclosing the information.

Bank Entities may use the confidential information for reporting purposes and the development and distribution of databases and market analyses so long as such confidential information is aggregated and anonymized prior to distribution, unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of this Agreement.

12.11 Attorneys’ Fees, Costs and Expenses. In any action or proceeding between Borrower and Bank arising out of or relating to the Loan Documents, Bank shall be entitled to recover its reasonable attorneys’ fees and other costs and expenses incurred, in addition to any other relief to which it may be entitled.

12.12 Right of Set Off. Borrower hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the Obligations. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

12.13 Electronic Execution of Documents. The words “execution,” “signed,” “signature” and words of like import in any Loan Document shall be deemed to include electronic signatures or the keeping of records in electronic form, each of which shall be of the same legal effect, validity and enforceability as a manually executed signature or the use of a paper-based recordkeeping systems, as the case may be, to the extent and as provided for in any applicable law, including, without limitation, any state law based on the Uniform Electronic Transactions Act.

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12.14 Captions. The headings used in this Agreement are for convenience only and shall not affect the interpretation of this Agreement.

12.15 Construction of Agreement. The parties mutually acknowledge that they and their attorneys have participated in the preparation and negotiation of this Agreement. In cases of uncertainty this Agreement shall be construed without regard to which of the parties caused the uncertainty to exist.

12.16 Relationship. The relationship of the parties to this Agreement is determined solely by the provisions of this Agreement. The parties do not intend to create any agency, partnership, joint venture, trust, fiduciary or other relationship with duties or incidents different from those of parties to an arm’s-length contract.

12.17 Third Parties. Nothing in this Agreement, whether express or implied, is intended to: (a) confer any benefits, rights or remedies under or by reason of this Agreement on any Persons other than the express parties to it and their respective permitted successors and assigns; (b) relieve or discharge the obligation or liability of any Person not an express party to this Agreement; or (c) give any Person not an express party to this Agreement any right of subrogation or action against any party to this Agreement.

12.18 Borrower Agreement; Cross-Collateralization; Cross-Default; Conflicts. Both this Agreement and the EXIM Borrower Agreement shall continue in full force and effect, and all rights and remedies under this Agreement and the EXIM Borrower Agreement are cumulative. The term “Obligations” as used in this Agreement and in the EXIM Borrower Agreement shall include without limitation the obligation to pay when due all loans made pursuant to the EXIM Borrower Agreement (the “EXIM Loans”) and all interest thereon and the obligation to pay when due all Advances made pursuant to the terms of this Agreement and all interest thereon. Without limiting the generality of the foregoing, the security interest granted herein covering all “Collateral” as defined in this Agreement and as defined in the EXIM Borrower Agreement shall secure all EXIM Loans and all Advances and all interest thereon, and all other Obligations. Any Event of Default under this Agreement shall also constitute a default under the EXIM Borrower Agreement, and any default under the EXIM Borrower Agreement shall also constitute an Event of Default under this Agreement. In the event Bank assigns its rights under this Agreement and/or under any note evidencing EXIM Loans and/or its rights under the Borrower Agreement and/or under any note evidencing Advances, to any third party, including, without limitation, the EXIM Bank, whether before or after the occurrence of any Event of Default, Bank shall have the right (but not any obligation), in its sole discretion, to allocate and apportion Collateral to the EXIM Borrower Agreement and/or note assigned and to specify the priorities of the respective security interests in such Collateral between itself and the assignee, all without notice to or consent of the Borrower. Should any term of the Agreement conflict with any term of the EXIM Borrower Agreement, the more restrictive term in either agreement shall govern Borrower.

13 DEFINITIONS

13.1 Definitions. As used in the Loan Documents, the word “shall” is mandatory, the word “may” is permissive, the word “or” is not exclusive, the words “includes” and “including” are not limiting, the singular includes the plural, and numbers denoting amounts that are set off in brackets are negative. As used in this Agreement, the following capitalized terms have the following meanings:

“Account” is any “account” as defined in the Code with such additions to such term as may hereafter be made, and includes, without limitation, all accounts receivable and other sums owing to Borrower.

“Account Debtor” is any “account debtor” as defined in the Code with such additions to such term as may hereafter be made.

“Account Transition Period” is defined in Section 6.8(a).

“Adjusted Quick Ratio” is, as of any date of measurement, the ratio of (i) the sum of (a) Borrower’s unrestricted cash at Bank plus (b) Borrower’s net billed accounts receivable that are aged less than ninety (90) days divided by (ii) the difference between (a) Current Liabilities minus accrued but unpaid Series A and Series B Dividends.

“Advance” or “Advances” means an advance (or advances) under the Revolving Line.

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“Affiliate” is, with respect to any Person, each other Person that owns or controls directly or indirectly the Person, any Person that controls or is controlled by or is under common control with the Person, and each of that Person’s senior executive officers, directors, partners and, for any Person that is a limited liability company, that Person’s managers and members.

“Agreement” is defined in the preamble hereof.

“Aspen Aerogels Rhode Island” is Aspen Aerogels Rhode Island LLC, a Rhode Island limited liability company and wholly owned Subsidiary of Borrower.

“Aspen GmbH” is Aspen Aerogels Germany GmbH, a company organized under the laws of the Federal Republic of Germany.

“Availability Amount” is (a) the lesser of (i) the Revolving Line minus any amounts outstanding under the Export-Import Agreement or (ii) the amount available under the Borrowing Base minus (b) the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), minus (c) the FX Reduction Amount, minus (d) any amounts used for Cash Management Services, and minus (e) the outstanding principal balance of any Advances. The aggregate amount of all Advances (including, without limitation, the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), any outstanding FX Reduction Amount and any amounts used for Cash Management Services) under this Agreement outstanding at any time together with all Credit Extensions made pursuant to the Export-Import Agreement outstanding at any time shall not exceed Ten Million Dollars ($10,000,000).

“Bank” is defined in the preamble hereof.

“Bank Expenses” are all audit fees and expenses, costs, and expenses (including reasonable attorneys’ fees and expenses) for preparing, amending, negotiating, administering, defending and enforcing the Loan Documents (including, without limitation, those incurred in connection with appeals or Insolvency Proceedings) or otherwise incurred with respect to Borrower or any Guarantor.

“Borrower” is defined in the preamble hereof.

“Borrower’s Books” are all Borrower’s books and records including ledgers, federal and state tax returns, records regarding Borrower’s assets or liabilities, the Collateral, business operations or financial condition, and all computer programs or storage or any equipment containing such information.

“Borrowing Base” is (a) eighty percent (80%) of Eligible Accounts, as determined by Bank from Borrower’s most recent Borrowing Base Certificate; provided, however, that Bank may decrease the foregoing percentage in its good faith business judgment based on events, conditions, contingencies, or risks which, as determined by Bank, may adversely affect the Collateral.

“Borrowing Base Certificate” is that certain certificate included within each Transaction Report.

“Borrowing Resolutions” are, with respect to any Person, those resolutions adopted by such Person’s Board of Directors or other appropriate body and delivered by such Person to Bank approving the Loan Documents to which such Person is a party and the transactions contemplated thereby, together with a certificate executed by its secretary on behalf of such Person certifying that (a) such Person has the authority to execute, deliver, and perform its obligations under each of the Loan Documents to which it is a party, (b) attached as Exhibit A to such certificate is a true, correct, and complete copy of the resolutions then in full force and effect authorizing and ratifying the execution, delivery, and performance by such Person of the Loan Documents to which it is a party, (c) the name(s) of the Person(s) authorized to execute the Loan Documents on behalf of such Person, together with a sample of the true signature(s) of such Person(s), and (d) Bank may conclusively rely on such certificate unless and until such Person shall have delivered to Bank a further certificate canceling or amending such prior certificate.

“Business Day” is any day that is not a Saturday, Sunday or a day on which Bank is closed.

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“Cabot License Agreement” means that certain Cross License Agreement dated April 1, 2006 by and between Cabot Corporation and Borrower, as amended by that certain Settlement Agreement and First Amendment to Cross License Agreement dated as of September 21, 2007.

“Capital Expenditures” means, with respect to any Person for any period, the sum of (a) the aggregate of all expenditures by such Person and its Subsidiaries during such period that are capital expenditures as determined in accordance with GAAP, whether such expenditures are paid in cash or financed, plus (b) to the extent not covered by clause (a), the aggregate of all expenditures by such Person and its Subsidiaries during such period to acquire by purchase or otherwise the business or capitalized assets or the capital stock of any other Person.

“Cash Equivalents” means (a) marketable direct obligations issued or unconditionally guaranteed by the United States or any agency or any State thereof having maturities of not more than one (1) year from the date of acquisition; (b) commercial paper maturing no more than one (1) year after its creation and having the highest rating from either Standard & Poor’s Ratings Group or Moody’s Investors Service, Inc., (c) Bank’s certificates of deposit issued maturing no more than one (1) year after issue; and (d) money market funds at least ninety-five percent (95%) of the assets of which constitute Cash Equivalents of the kinds described in clauses (a) through (c) of this definition.

“Cash Management Services” is defined in Section 2.1.4.

“Code” is the Uniform Commercial Code, as the same may, from time to time, be enacted and in effect in the Commonwealth of Massachusetts; provided, that, to the extent that the Code is used to define any term herein or in any Loan Document and such term is defined differently in different Articles or Divisions of the Code, the definition of such term contained in Article or Division 9 shall govern; provided further, that in the event that, by reason of mandatory provisions of law, any or all of the attachment, perfection, or priority of, or remedies with respect to, Bank’s Lien on any Collateral is governed by the Uniform Commercial Code in effect in a jurisdiction other than the Commonwealth of Massachusetts, the term “Code” shall mean the Uniform Commercial Code as enacted and in effect in such other jurisdiction solely for purposes of the provisions thereof relating to such attachment, perfection, priority, or remedies and for purposes of definitions relating to such provisions.

“Collateral” is any and all properties, rights and assets of Borrower described on Exhibit A.

“Collateral Account” is any Deposit Account, Securities Account, or Commodity Account.

“Commodity Account” is any “commodity account” as defined in the Code with such additions to such term as may hereafter be made.

“Communication” is defined in Section 10.

“Compliance Certificate” is that certain certificate in the form attached hereto as Exhibit B.

“Contingent Obligation” is, for any Person, any direct or indirect liability, contingent or not, of that Person for (a) any indebtedness, lease, dividend, letter of credit or other obligation of another such as an obligation, in each case directly or indirectly guaranteed, endorsed, co made, discounted or sold with recourse by that Person, or for which that Person is directly or indirectly liable; (b) any obligations for undrawn letters of credit for the account of that Person; and (c) all obligations from any interest rate, currency or commodity swap agreement, interest rate cap or collar agreement, or other agreement or arrangement designated to protect a Person against fluctuation in interest rates, currency exchange rates or commodity prices; but “Contingent Obligation” does not include endorsements in the ordinary course of business. The amount of a Contingent Obligation is the stated or determined amount of the primary obligation for which the Contingent Obligation is made or, if not determinable, the maximum reasonably anticipated liability for it determined by the Person in good faith; but the amount may not exceed the maximum of the obligations under any guarantee or other support arrangement.

“Control Agreement” is any control agreement entered into among the depository institution at which Borrower maintains a Deposit Account or the securities intermediary or commodity intermediary at which Borrower maintains a Securities Account or a Commodity Account, Borrower, and Bank pursuant to which Bank obtains control (within the meaning of the Code) over such Deposit Account, Securities Account, or Commodity Account.

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“Copyrights” are any and all copyright rights, copyright applications, copyright registrations and like protections in each work or authorship and derivative work thereof, whether published or unpublished and whether or not the same also constitutes a trade secret.

“Credit Extension” is any Advance, EXIM Loan, Letter of Credit, FX Forward Contract, amount utilized for Cash Management Services, or any other extension of credit by Bank for Borrower’s benefit.

“Current Liabilities” are all Obligations and liabilities of Borrower owed to Bank, plus, without duplication, the aggregate amount of Borrower’s Total Liabilities that mature within one (1) year.

“Default” means any event which with notice or passage of time or both, would constitute an Event of Default.

“Default Rate” is defined in Section 2.3(b).

“Deferred Revenue” is all amounts received or invoiced in advance of performance under contracts and not yet recognized as revenue.

“Deposit Account” is any “deposit account” as defined in the Code with such additions to such term as may hereafter be made.

“Designated Deposit Account” is Borrower’s deposit account, account number                     , maintained with Bank.

“Dollars,” “dollars” or use of the sign “$” means only lawful money of the United States and not any other currency, regardless of whether that currency uses the “$” sign to denote its currency or may be readily converted into lawful money of the United States.

“Dollar Equivalent” is, at any time, (a) with respect to any amount denominated in Dollars, such amount, and (b) with respect to any amount denominated in a Foreign Currency, the equivalent amount therefor in Dollars as determined by Bank at such time on the basis of the then-prevailing rate of exchange in San Francisco, California, for sales of the Foreign Currency for transfer to the country issuing such Foreign Currency.

“Effective Date” is the date Bank executes this Agreement and as indicated on the signature page hereof.

“Eligible Accounts” means Accounts which arise in the ordinary course of Borrower’s business that meet all Borrower’s representations and warranties in Section 5.3. Bank reserves the right at any time and from time to time after the Effective Date upon notice to Borrower, to adjust any of the criteria set forth below and to establish new criteria in its good faith business judgment. Without limiting the fact that the determination of which Accounts are eligible for borrowing is a matter of Bank’s good faith judgment, the following (“Minimum Eligibility Requirements”) are the minimum requirements for an Account to be an Eligible Account. Unless Bank agrees otherwise in writing, Eligible Accounts shall not include:

(a) Accounts for which the Account Debtor is Borrower’s Affiliate, officer, employee, or agent;

(b) Accounts that the Account Debtor has not paid within ninety (90) days of invoice date regardless of invoice payment period terms;

(c) Accounts with credit balances over ninety (90) days from invoice date;

(d) Accounts owing from an Account Debtor, in which fifty percent (50%) or more of the Accounts have not been paid within ninety (90) days of invoice date;

(e) Accounts owing from an Account Debtor which does not have its principal place of business in the United States;

(f) Accounts billed and/or payable outside of the United States (sometimes called foreign invoiced accounts);

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(g) Accounts owing from an Account Debtor to the extent that Borrower is indebted or obligated in any manner to the Account Debtor (as creditor, lessor, supplier or otherwise — sometimes called “contra” accounts, accounts payable, customer deposits or credit accounts).

(h) Accounts owing from an Account Debtor which is a United States government entity or any department, agency, or instrumentality thereof unless Borrower has assigned its payment rights to Bank and the assignment has been acknowledged under the Federal Assignment of Claims Act of 1940, as amended;

(i) Accounts for demonstration or promotional equipment, or in which goods are consigned, or sold on a “sale guaranteed”, “sale or return”, “sale on approval”, or other terms if Account Debtor’s payment may be conditional;

(j) Accounts owing from an Account Debtor where goods or services have not yet been rendered to the Account Debtor (sometimes called memo billings or pre-billings);

(k) Accounts subject to contractual arrangements between Borrower and an Account Debtor where payments shall be scheduled or due according to completion or fulfillment requirements where the Account Debtor has a right of offset for damages suffered as a result of Borrower’s failure to perform in accordance with the contract (sometimes called contracts accounts receivable, progress billings, milestone billings, or fulfillment contracts);

(l) Accounts owing from an Account Debtor the amount of which may be subject to withholding based on the Account Debtor’s satisfaction of Borrower’s complete performance (but only to the extent of the amount withheld; sometimes called retainage billings);

(m) Accounts subject to trust provisions, subrogation rights of a bonding company, or a statutory trust;

(n) Accounts owing from an Account Debtor that has been invoiced for goods that have not been shipped to the Account Debtor unless Bank, Borrower, and the Account Debtor have entered into an agreement acceptable to Bank in its sole discretion wherein the Account Debtor acknowledges that (i) it has title to and has ownership of the goods wherever located, (ii) a bona fide sale of the goods has occurred, and (iii) it owes payment for such goods in accordance with invoices from Borrower (sometimes called “bill and hold” accounts);

(o) Accounts for which the Account Debtor has not been invoiced;

(p) Accounts that represent non-trade receivables or that are derived by means other than in the ordinary course of Borrower’s business;

(q) Accounts for which Borrower has permitted Account Debtor’s payment to extend beyond ninety (90) days;

(r) Accounts arising from chargebacks, debit memos or other payment deductions taken by an Account Debtor;

(s) Accounts arising from product returns and/or exchanges (sometimes called “warranty” or “RMA” accounts);

(t) Accounts in which the Account Debtor disputes liability or makes any claim (but only up to the disputed or claimed amount), or if the Account Debtor is subject to an Insolvency Proceeding, or becomes insolvent, or goes out of business;

(u) Accounts owing from an Account Debtor with respect to which Borrower has received Deferred Revenue (but only to the extent of such Deferred Revenue);

(v) Accounts owing from an Account Debtor, whose total obligations to Borrower exceed twenty-five percent (25%) of all Accounts, for the amounts that exceed that percentage, unless Bank approves in writing;

(w) Accounts for which Bank in its good faith business judgment determines collection to be doubtful, including, without limitation, accounts represented by “refreshed” or “recycled” invoices; and

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(x) other Accounts Bank deems ineligible in the exercise of its good faith business judgment.

“Equipment” is all “equipment” as defined in the Code with such additions to such term as may hereafter be made, and includes without limitation all machinery, fixtures, goods, vehicles (including motor vehicles and trailers), and any interest in any of the foregoing.

“ERISA” is the Employee Retirement Income Security Act of 1974, and its regulations.

“Event of Default” is defined in Section 8.

“EXIM Bank” is the Export-Import Bank of the United States.

“EXIM Borrower Agreement” is defined in the Export-Import Agreement.

“EXIM Guaranty” is that certain Master Guarantee Agreement, by and between Bank and EXIM Bank, dated as of November 1, 2005, as amended and in effect as of the date hereof.

“EXIM Loan Documents” are all documents and agreements executed in connection with the Export-Import Agreement, including, without limitation, the EXIM Borrower Agreement and the EXIM Promissory Note (as defined in the Export-Import Agreement), as each may be amended from time to time.

“Export-Import Agreement” is that certain Export-Import Bank Loan and Security Agreement, dated as of the date hereof, by and between Borrower and Bank.

“EXIM Loans” is defined in Section 12.18.

“Foreign Currency” means lawful money of a country other than the United States.

“Funding Date” is any date on which a Credit Extension is made to or for the account of Borrower which shall be a Business Day.

“FX Business Day” is any day when (a) Bank’s Foreign Exchange Department is conducting its normal business and (b) the Foreign Currency being purchased or sold by Borrower is available to Bank from the entity from which Bank shall buy or sell such Foreign Currency.

“FX Forward Contract” is defined in Section 2.1.3.

“FX Reduction Amount” is defined in Section 2.1.3.

“GAAP” is generally accepted accounting principles set forth in the opinions and pronouncements of the Accounting Principles Board of the American Institute of Certified Public Accountants and statements and pronouncements of the Financial Accounting Standards Board or in such other statements by such other Person as may be approved by a significant segment of the accounting profession, which are applicable to the circumstances as of the date of determination.

“General Intangibles” is all “general intangibles” as defined in the Code in effect on the date hereof with such additions to such term as may hereafter be made, and includes without limitation, claims, income and other tax refunds, security and other deposits, payment intangibles, contract rights, options to purchase or sell real or personal property, rights in all litigation presently or hereafter pending (whether in contract, tort or otherwise), insurance policies (including without limitation key man, property damage, and business interruption insurance), payments of insurance and rights to payment of any kind. Notwithstanding the foregoing, General Intangibles does not include any Intellectual Property.

“Governmental Approval” is any consent, authorization, approval, order, license, franchise, permit, certificate, accreditation, registration, filing or notice, of, issued by, from or to, or other act by or in respect of, any Governmental Authority.

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“Governmental Authority” is any nation or government, any state or other political subdivision thereof, any agency, authority, instrumentality, regulatory body, court, central bank or other entity exercising executive, legislative, judicial, taxing, regulatory or administrative functions of or pertaining to government, any securities exchange and any self-regulatory organization.

“Guarantor” is any present or future guarantor of the Obligations, including, without limitation, Aspen Aerogels Rhode Island.

“Guaranty Agreement” is any present or future guaranty agreement pursuant to which any Guarantor guaranty’s repayment of the Obligations, including, without limitation, that certain Unconditional Guaranty, dated as of the date hereof, by Aspen Aerogels Rhode Island, in favor of Bank.

“Indebtedness” is (a) indebtedness for borrowed money or the deferred price of property or services, such as reimbursement and other obligations for surety bonds and letters of credit, (b) obligations evidenced by notes, bonds, debentures or similar instruments, (c) capital lease obligations, and (d) Contingent Obligations.

“Indemnified Person” is defined in Section 12.3.

“Insolvency Proceeding” is any proceeding by or against any Person under the United States Bankruptcy Code, or any other bankruptcy or insolvency law, including assignments for the benefit of creditors, compositions, extensions generally with its creditors, or proceedings seeking reorganization, arrangement, or other relief.

“Intellectual Property” means all of Borrower’s and/or Guarantor’s right, title, and interest in and to the following (including all rights under licenses thereof, including without limitation all right, title and interest of the Borrower under the Cabot License Agreement):

(a) Copyrights, Trademarks and Patents;

(b) any and all trade secrets and trade secret rights, including, without limitation, any rights to unpatented inventions, know-how, operating manuals;

(c) any and all source code;

(d) any and all design rights which may be available to a Borrower;

(e) any and all claims for damages by way of past, present and future infringement of any of the foregoing, with the right, but not the obligation, to sue for and collect such damages for said use or infringement of the Intellectual Property rights identified above; and

(f) all amendments, renewals and extensions of any of the Copyrights, Trademarks or Patents.

“Inventory” is all “inventory” as defined in the Code in effect on the date hereof with such additions to such term as may hereafter be made, and includes without limitation all merchandise, raw materials, parts, supplies, packing and shipping materials, work in process and finished products, including without limitation such inventory as is temporarily out of Borrower’s custody or possession or in transit and including any returned goods and any documents of title representing any of the above.

“Investment” is any beneficial ownership interest in any Person (including stock, partnership interest or other securities), and any loan, advance or capital contribution to any Person.

“Key Person” is Borrower’s Chief Executive Officer and President who is, as of the Effective Date, Don Young.

“Letter of Credit” means a standby letter of credit issued by Bank or another institution based upon an application, guarantee, indemnity or similar agreement on the part of Bank as set forth in Section 2.1.2.

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“Letter of Credit Application” is defined in Section 2.1.2(a).

“Letter of Credit Reserve” has the meaning set forth in Section 2.1.2(d).

“Lien” is a claim, mortgage, deed of trust, levy, charge, pledge, security interest or other encumbrance of any kind, whether voluntarily incurred or arising by operation of law or otherwise against any property.

“Liquidity Threshold” is, on and after the Effective Date, provided no Default or Event of Default has occurred and is continuing, the period (i) commencing on the first (1st) day in which Borrower has, for each consecutive day in the immediately preceding thirty (30) day period, maintained an Adjusted Quick Ratio, as determined by Bank, in its reasonable discretion, in an amount at all times greater than or equal to 1.00:1.00, as determined by Bank, in its sole discretion; and (ii) terminating on the earlier to occur of (A) the occurrence of a Default or an Event of Default; and (B) the first day thereafter in which Borrower fails to maintain an Adjusted Quick Ratio greater than or equal to 1.00:1.00, as determined by Bank, in its reasonable discretion. Thereafter, in order for the Liquidity Threshold to be applicable, Borrower must achieve an Adjusted Quick Ratio in an amount greater than or equal to 1.00:1.00 each consecutive day for thirty (30) consecutive days, as determined by Bank, in its reasonable discretion. Borrower shall give Bank prior-written notice of Borrower’s achievement of the Liquidity Threshold.

“Loan Documents” are, collectively, this Agreement, the EXIM Loan Documents, the Perfection Certificates, the Stock Pledge Agreement, the PJC Intercreditor Agreement, any Guaranty Agreement, any Security Agreement, any note, or notes or guaranties executed by Borrower or any Guarantor, and any other present or future agreement between Borrower any Guarantor and/or for the benefit of Bank in connection with this Agreement, all as amended, restated, or otherwise modified.

“Material Adverse Change” is (a) a material impairment in the perfection or priority of Bank’s Lien in the Collateral or in the value of such Collateral; (b) a material adverse change in the business, operations, or condition (financial or otherwise) of Borrower and its Subsidiaries, taken as a whole; (c) a material impairment of the prospect of repayment of any portion of the Obligations or (d) Bank determines, after consultation with Borrower, based upon information available to it and in its reasonable judgment, that there is a substantial likelihood that Borrower shall fail to comply with one or more of the financial covenants in Section 6 during the next succeeding financial reporting period.

“Minimum Eligibility Requirements” is defined in the defined term “Eligible Accounts”.

“Note Purchase Agreement” is that certain Subordinated Note and Warrant Purchase Agreement, dated as of the date hereof, by and among Borrower, PJC Capital LLC and the other “Purchasers” named therein.

“Obligations” are Borrower’s obligation to pay when due any debts, principal, interest, Bank Expenses and other amounts Borrower owes Bank now or later, whether under this Agreement, the other Loan Documents, the Export-Import Agreement, the other EXIM Loan Documents, or otherwise, including, without limitation, all obligations relating to letters of credit (including reimbursement obligations for drawn and undrawn letters of credit), cash management services, and foreign exchange contracts, if any, and including interest accruing after Insolvency Proceedings begin and debts, liabilities, or obligations of Borrower assigned to Bank, and to perform Borrower’s duties under the Loan Documents.

“Operating Documents” are, for any Person, such Person’s formation documents, as certified with the Secretary of State of such Person’s state of formation on a date that is no earlier than 30 days prior to the Effective Date, and, (a) if such Person is a corporation, its bylaws in current form, (b) if such Person is a limited liability company, its limited liability company agreement (or similar agreement), and (c) if such Person is a partnership, its partnership agreement (or similar agreement), each of the foregoing with all current amendments or modifications thereto.

“Patents” means all patents, patent applications and like protections including without limitation improvements, divisions, continuations, renewals, reissues, extensions and continuations-in-part of the same.

“Payment” means all checks, wire transfers and other items of payment received by Bank (including proceeds of Accounts and payment of all the Obligations in full) for credit to Borrower’s outstanding Credit Extensions or, if the balance of the Credit Extensions has been reduced to zero, for credit to its Deposit Accounts.

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“Perfection Certificate” is defined in Section 5.1.

“Permitted Indebtedness” is:

(a) Borrower’s Indebtedness to Bank under this Agreement and the other Loan Documents;

(b) Indebtedness existing on the Effective Date and shown on the Perfection Certificate;

(c) Subordinated Debt, including, without limitation, the Indebtedness owed to PJC Capital LLC and the other “Holders” as such term is defined in the Note Purchase Agreement, as described in and subject to the PJC Intercreditor Agreement, and guaranties of any such Subordinated Debt by any Subsidiary of the Borrower;

(d) Indebtedness owed to the Massachusetts Development Finance Agency pursuant to the Borrower’s 6% term loan dated January 12, 2005, in the original principal amount of $1,500,000, repayable in equal monthly installments over 84 months, secured by leasehold improvements and lab equipment located at 30 Forbes Road, Northborough, MA, the outstanding principal and accrued but unpaid interest of which is, as of November 30, 2010, $297,448;

(e) unsecured Indebtedness to trade creditors incurred in the ordinary course of business;

(f) Indebtedness secured by Liens permitted to clauses (a) and (c) of the definition of “Permitted Liens” hereof;

(g) Indebtedness (i) of Subsidiaries owed to Borrower for any Subsidiary that has executed a Security Agreement in favor of Bank and (ii) of Subsidiaries owed to Borrower in an aggregate amount, together with Investments permitted in connection with clause (d) of the definition of “Permitted Investments”, not to exceed Two Hundred Fifty Thousand Dollars ($250,000) in any fiscal year;

(h) extensions, refinancings, modifications, amendments and restatements of any items of Permitted Indebtedness (a) through (e) above, provided that the principal amount thereof is not increased or the terms thereof are not modified to impose more burdensome terms upon Borrower or its Subsidiary, as the case may be; and

(i) other unsecured Indebtedness in an aggregate amount not to exceed Two hundred Fifty Thousand Dollars ($250,000);

“Permitted Investments” are:

(a) Investments shown on the Perfection Certificate and existing on the Effective Date;

(b) Cash Equivalents;

(c) Investments consisting of the endorsement of negotiable instruments for deposit or collection or similar transactions in the ordinary course of Borrower’s business;

(d) Investments (i) by Borrower in any Subsidiary that has executed a Security Agreement in favor of Bank and (ii) by Borrower in any Subsidiary, in an aggregate amount, together with any Indebtedness described in clause (g) of the definition of “Permitted Indebtedness”, not to exceed Two Hundred Fifty Thousand Dollars ($250,000) in any fiscal year;

(e) Investments (including debt obligations) received in connection with the bankruptcy or reorganization of customers or suppliers and in settlement of delinquent obligations of, and other disputes with, customers or suppliers arising in the ordinary course of business; and

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(f) Investments consisting of notes receivable of, or prepaid royalties and other credit extensions, to customers and suppliers who are not Affiliates, in the ordinary course of business; provided that this paragraph (f) shall not apply to Investments of Borrower in any Subsidiary.

“Permitted Liens” are:

(a) (i) Liens existing on the Effective Date and shown on the Perfection Certificate or arising under this Agreement and the other Loan Documents and (ii) subject to the terms and conditions of the PJC Intercreditor Agreement, Liens in favor of PJC Capital LLC, as collateral agent;

(b) Liens for taxes, fees, assessments or other government charges or levies, either (i) not due and payable or (ii) being contested in good faith and for which Borrower maintains adequate reserves on its Books, provided that no notice of any such Lien has been filed or recorded under the Internal Revenue Code of 1986, as amended, and the Treasury Regulations adopted thereunder;

(c) purchase money Liens (i) on Equipment acquired or held by Borrower incurred for financing the acquisition of the Equipment securing no more than Two Hundred Fifty Thousand Dollars ($250,000) in the aggregate amount outstanding, or (ii) existing on Equipment when acquired, if the Lien is confined to the property and improvements and the proceeds of the Equipment;

(d) Liens to secure payment of workers’ compensation, employment insurance, old-age pensions, social security and other like obligations incurred in the ordinary course of business (other than Liens imposed by ERISA);

(e) Liens incurred in the extension, renewal or refinancing of the indebtedness secured by Liens described in (a) through (c), but any extension, renewal or replacement Lien must be limited to the property encumbered by the existing Lien and the principal amount of the indebtedness may not increase;

(f) leases or subleases of real property granted in the ordinary course of business, and leases, subleases, non-exclusive licenses or sublicenses of property (other than real property or Intellectual Property) granted in the ordinary course of Borrower’s business, if the leases, subleases, licenses and sublicenses do not prohibit granting Bank a security interest;

(g) non-exclusive license of Intellectual Property granted to third parties in the ordinary course of business, and licenses of Intellectual Property that could not result in a legal transfer of title of the licensed property that may be exclusive in respects other than territory and that may be exclusive as to territory only as to discreet geographical areas outside of the United States;

(h) Liens securing Permitted Indebtedness; and

(i) Liens arising from judgments, decrees or attachments in circumstances not constituting an Event of Default under Section 8.4 or 8.7.

“Person” is any individual, sole proprietorship, partnership, limited liability company, joint venture, company, trust, unincorporated organization, association, corporation, institution, public benefit corporation, firm, joint stock company, estate, entity or government agency.

“PJC Capital LLC” is PJC Capital LLC, a Delaware limited liability company and “Collateral Agent” under the Note Purchase Agreement.

“PJC Intercreditor Agreement” is that certain Intercreditor and Subordination Agreement, dated on or about the date hereof, by and between Bank, PJC Capital LLC and the other subordinated creditors named therein.

“Prime Rate” is the greater of (i) four percent (4.00%) per annum, and (ii) Bank’s most recently announced “prime rate,” even if it is not Bank’s lowest rate.

“Registered Organization” is any “registered organization” as defined in the Code with such additions to such term as may hereafter be made.

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“Requirement of Law” is as to any Person, the organizational or governing documents of such Person, and any law (statutory or common), treaty, rule or regulation or determination of an arbitrator or a court or other Governmental Authority, in each case applicable to or binding upon such Person or any of its property or to which such Person or any of its property is subject.

“Reserves” means, as of any date of determination, such amounts as Bank may from time to time establish and revise in good faith reducing the amount of Advances, Letters of Credit and other financial accommodations which would otherwise be available to Borrower under the lending formulas: (a) to reflect events, conditions, contingencies or risks which, as determined by Bank in good faith, do or may affect (i) the Collateral or any other property which is security for the Obligations or its value (including without limitation any increase in delinquencies of Accounts), (ii) the assets or business of Borrower or any guarantor, or (iii) the security interests and other rights of Bank in the Collateral (including the enforceability, perfection and priority thereof); or (b) to reflect Bank’s good faith belief that any collateral report or financial information furnished by or on behalf of Borrower or any guarantor to Bank is or may have been incomplete, inaccurate or misleading in any material respect; or (c) in respect of any state of facts which Bank determines in good faith constitutes an Event of Default or may, with notice or passage of time or both, constitute an Event of Default.

“Responsible Officer” is any of the Chief Executive Officer, President, Chief Financial Officer and Controller of Borrower.

“Revolving Line” is an Advance or Advances (including, without limitation, Advances made pursuant to the Export-Import Agreement) in an amount under this Agreement and the Export-Import Agreement not to exceed Ten Million Dollars ($10,000,000) at any time.

“Revolving Line Maturity Date” is March 31, 2013 (two (2) years after the Effective Date).

“SEC” shall mean the Securities and Exchange Commission, any successor thereto, and any analogous Governmental Authority

“Securities Account” is any “securities account” as defined in the Code with such additions to such term as may hereafter be made.

“Security Agreement” is any present or future security agreement pursuant to which any Person pledges its Collateral to Bank as security for the Obligations, including, without limitation, that certain Security Agreement, dated as of the date hereof, by Aspen Aerogels Rhode Island, in favor of Bank.

“Series A and Series B Dividends” are, as of any date of measurement, the dividends that shall have accrued on shares of the Borrower’s Series A Preferred Stock and Series B Preferred Stock, whether or not declared or paid.

“Stock Pledge Agreement” is that certain Stock Pledge Agreement, dated as of the date hereof, by and between Borrower and Bank.

“Subordinated Debt” is indebtedness incurred by Borrower subordinated to all of Borrower’s now or hereafter indebtedness to Bank (pursuant to a subordination, intercreditor, or other similar agreement in form and substance satisfactory to Bank entered into between Bank and the other creditor), on terms acceptable to Bank, including, without limitation, the Subordinated Debt described in and subject to the PJC Intercreditor Agreement.

“Subsidiary” is, as to any Person, a corporation, partnership, limited liability company or other entity of which shares of stock or other ownership interests having ordinary voting power (other than stock or such other ownership interests having such power only by reason of the happening of a contingency) to elect a majority of the board of directors or other managers of such corporation, partnership or other entity are at the time owned, or the management of which is otherwise controlled, directly or indirectly through one or more intermediaries, or both, by such Person. Unless the context otherwise requires, each reference to a Subsidiary herein shall be a reference to a Subsidiary of Borrower or Guarantor.

“Tangible Net Worth” is, on any date, the consolidated total assets of Borrower and its Subsidiaries minus (a) any amounts attributable to (i) goodwill, (ii) intangible items including unamortized debt discount and expense, Patents, Trademarks, Copyrights, and research and development expenses except prepaid expenses, (iii) notes, accounts receivable and other obligations owing to Borrower from its officers or other Affiliates, and (iv) reserves not already deducted from assets, minus (b) Total Liabilities plus (c) Subordinated Debt.

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“Total Liabilities” is on any day, all obligations that should, under GAAP, be classified as liabilities on Borrower’s consolidated balance sheet, including all Indebtedness.

“Trademarks” means any trademark and servicemark rights, whether registered or not, applications to register and registrations of the same and like protections, and the entire goodwill of the business of Borrower connected with and symbolized by such trademarks.

“Transaction Report” is the Bank’s standard reporting package provided by Bank to Borrower.

“Transfer” is defined in Section 7.1.

“Unused Revolving Line Facility Fee” is defined in Section 2.4(d).

[Signature page follows.]

IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the Effective Date.

BORROWER:

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title:   Chief Financial Officer
BANK: SILICON VALLEY BANK
By:	/s/ Thomas Kelly
Name: Thomas Kelly
Title:  Vice President

Effective Date: March 31, 2011

[Signature Page to Loan and Security Agreement]

EXHIBIT A — COLLATERAL DESCRIPTION

The Collateral consists of all of Borrower’s right, title and interest in and to the following personal property:

All goods, Accounts (including health-care receivables), Equipment, Inventory, contract rights (except as provided below) or rights to payment of money, leases, license agreements (except as provided below), franchise agreements, General Intangibles (except as provided below), commercial tort claims, documents, instruments (including any promissory notes), chattel paper (whether tangible or electronic), cash, deposit accounts, fixtures, letters of credit rights (whether or not the letter of credit is evidenced by a writing), securities, and all other investment property, supporting obligations, and financial assets, whether now owned or hereafter acquired, wherever located; and

all Borrower’s Books relating to the foregoing, and any and all claims, rights and interests in any of the above and all substitutions for, additions, attachments, accessories, accessions and improvements to and replacements, products, proceeds and insurance proceeds of any or all of the foregoing.

Notwithstanding the foregoing, the Collateral does not include any Intellectual Property; provided however, the Collateral shall include all Accounts and all proceeds of Intellectual Property. Pursuant to the terms of a certain negative pledge arrangement with Bank, Borrower has agreed not to encumber any of its Intellectual Property without Bank’s prior written consent.

EXHIBIT B

COMPLIANCE CERTIFICATE

TO: SILICON VALLEY BANK	Date:
FROM: ASPEN AEROGELS, INC.

The undersigned authorized officer of Aspen Aerogels, Inc. (“Borrower”) certifies that under the terms and conditions of the Loan and Security Agreement between Borrower and Bank (the “Agreement”), (1) Borrower is in complete compliance for the period ending                         with all required covenants except as noted below, (2) there are no Events of Default, (3) all representations and warranties in the Agreement are true and correct in all material respects on this date except as noted below; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date, (4) Borrower, and each of its Subsidiaries, has timely filed all required tax returns and reports, and Borrower has timely paid all foreign, federal, state and local taxes, assessments, deposits and contributions owed by Borrower except as otherwise permitted pursuant to the terms of Section 5.9 of the Agreement, and (5) no Liens have been levied or claims made against Borrower or any of its Subsidiaries, if any, relating to unpaid employee payroll or benefits of which Borrower has not previously provided written notification to Bank. Attached are the required documents supporting the certification. The undersigned certifies that these are prepared in accordance with GAAP consistently applied from one period to the next except as explained in an accompanying letter or footnotes. The undersigned acknowledges that no borrowings may be requested at any time or date of determination that Borrower is not in compliance with any of the terms of the Agreement, and that compliance is determined not just at the date this certificate is delivered. Capitalized terms used but not otherwise defined herein shall have the meanings given them in the Agreement.

Please indicate compliance status by circling Yes/No under “Complies” column.

Reporting Covenant	Required	Complies
Monthly financial statements with * Compliance Certificate	Monthly within 30 days		Yes No
Annual financial statement (CPA Audited) + CC	FYE within 180 days		Yes No
10-Q, 10-K and 8-K	Within 5 days after filing with SEC		Yes No
A/R & A/P Agings (including EXIM), inventory reports and Borrowing Base Certificate*	Monthly within 15 days (quarterly within 15 days if no outstanding Credit Extensions)		Yes No
Transaction Reports	Weekly (monthly within 15 days when Borrower has achieved Liquidity Threshold) and with each request for a Credit Extension)		Yes No
Invoices for 10% of outstanding balance of EXIM A/R*	Within 15 days after the end of each quarter		Yes No

* See Section 8.2 for 5 Business Day cure period

The following Intellectual Property was registered after the Effective Date (if no registrations, state “None”)

Financial Covenant	Required		Actual	Complies
Maintain as indicated:
Liquidity (at all times, certified monthly)	$	3,000,000	$		Yes No
Tangible Net Worth (at all times, certified monthly)	$	40,000,000	$		Yes No

1

The following financial covenant analyses and information set forth in Schedule 1 attached hereto are true and accurate as of the date of this Certificate.

The following are the exceptions with respect to the certification above: (If no exceptions exist, state “No exceptions to note.”)

Aspen Aerogels, Inc.	BANK USE ONLY
	Received by:
By:	AUTHORIZED SIGNER
Name: Title:	Date:
	Verified:
	AUTHORIZED SIGNER
	Date:
	Compliance Status:                             Yes                      No

2

Schedule 1 to Compliance Certificate

Financial Covenants of Borrower

In the event of a conflict between this Schedule and the Loan Agreement, the terms of the Loan Agreement shall govern.

Dated:                         

I. Liquidity (Section 6.9(a))

Required: Maintain Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).

Actual:

A.	Borrower’s unrestricted cash at Bank	$
B.	Unused Availability Amount	$
C.	LIQUIDITY (line A plus line B)	$

Is line C equal to or greater than $3,000,000?

                         No, not in compliance                      Yes, in compliance

3

II.	Tangible Net Worth (Section 6.9(b))
Required:     Maintain a Tangible Net Worth of at least Forty Million Dollars ($40,000,000).

Actual:

A.	Aggregate value of total assets of Borrower and its Subsidiaries	$
B.	Aggregate value of goodwill of Borrower	$
C.	Aggregate value of intangible items including unamortized debt discount and expense, Patents, Trademarks, Copyrights, and research and development expenses except prepaid expenses	$
D.	Aggregate value of any notes, accounts receivable and other obligations owing to Borrower from its officers or other Affiliates, and
E.	Aggregate value of any reserves not already deducted from assets	$
F.	Total Liabilities of Borrower (excluding Subordinated Debt)	$
G.	TANGIBLE NET WORTH (line A minus line B minus line C minus line D minus line E minus line F)	$

Is line G equal to or greater than $40,000,000?

                         No, not in compliance                      Yes, in compliance

CONSENT AND FIRST LOAN MODIFICATION AGREEMENT

This Consent and First Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of June 1, 2011, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the “Intellectual Property Collateral” as described in a certain Intellectual Property Security Agreement, dated as of March 31, 2011 (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 7.9 (Subordinated Debt) thereof:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject.”

and inserting in lieu thereof the following:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement without the prior written consent of Bank.”

2 The Loan Agreement shall be amended by deleting the following text appearing as Section 8.9 (Subordinated Debt) thereof:

“8.9 Subordinated Debt. Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement or the PJC Intercreditor Agreement.”

and inserting in lieu thereof the following:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement or the Fidelity Subordination Agreement; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder.”

3 The Loan Agreement shall be amended by deleting the following clause (i) from the definition of “Permitted Indebtedness” in Section 13.1 thereof:

“(i) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

and inserting in lieu thereof the following:

“(i) (i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement and (ii) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

4 The Loan Agreement shall be amended by inserting the following new definitions in Section 13.1 thereof in their appropriate alphabetical order:

““Fidelity Creditors” is each “Purchaser” from time to time party to the Fidelity Note Purchase Agreement.

“Fidelity Note” and “Fidelity Notes” is each Convertible Promissory Note issued pursuant to the Fidelity Note Purchase Agreement.

“Fidelity Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of the date hereof, by and between Borrower and the “Purchasers” party thereto, in a maximum principal amount equal to Twenty Five Million Dollars ($25,000,000), together with an executed copy of each Fidelity Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“Fidelity Subordination Agreement” is that certain Subordination Agreement, dated as of the date hereof, by and between Bank and the Fidelity Creditors.”

4. ISSUANCE OF ADDITIONAL SUBORDINATED DEBT. The Borrower has requested that the Bank consent to the Borrower receiving proceeds from the issuance of additional unsecured Subordinated Debt to the Fidelity Creditors, as more fully described in the Fidelity Note Purchase Agreement, in substantially the form attached as Exhibit A hereto (such issuance hereafter referred to as the “Transaction”). The Bank has agreed to do so, but only upon and subject to the specific terms and conditions set forth herein.

5. CONSENT. In reliance upon the representations of the Borrower herein, Bank hereby consents to the consummation of the Transaction and waives any Event of Default that may otherwise arise under the Existing Loan Documents solely as a result of the consummation of the Transaction for all purposes under the Existing Loan Documents, subject to each of the Conditions Precedent described in Section 6 hereof. In addition, Bank hereby consents to the amendment to the Note Purchase Agreement, as evidenced by a certain Amendment No. 1 to Subordinated Note and Warrant Purchase Agreement, by and between borrower and the “Purchasers” signatory thereto, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion.

6. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. the Transaction shall be consummated upon terms substantially similar to those contained in the Fidelity Note Purchase Agreement attached at Exhibit A hereto, in each case without any material amendment or modification thereto (it being agreed that any amendment or modification to the Fidelity Note Purchase Agreement attached as Exhibit A hereto which may reasonably be considered materially adverse to the interests of the Bank shall be deemed to be material);

B. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

C. Bank shall have received executed copies of this Loan Modification Agreement, the Fidelity Note Purchase Agreement and the Fidelity Subordination Agreement;

D. Bank shall have received a copy of the executed Amendment No. 1 to Subordinated Note and Warrant Purchase Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

E. Bank shall have received an executed Subordination Agreement, dated as of the date hereof, by and between the Purchasers party to the Note Purchase Agreement and the Fidelity Creditors, in substantially the same form as the Fidelity Subordination Agreement;

F. After giving effect to the consent granted herein, this Loan Modification Agreement and the Fidelity Note Purchase Agreement, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt; and

G. such other documents and/or agreements as Bank may reasonably request.

7. FEES. Borrower shall reimburse Bank for all legal fees and expenses incurred in connection with this amendment to the Existing Loan Documents.

8. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate, no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse).

In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in a certain Perfection Certificate, dated as of March 31, 2011, and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remains true and correct in all material respects as of the date hereof.

9. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

10. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

11. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

12. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

13. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

14. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

15. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of

Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

16. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

17. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER: ASPEN AEROGELS, INC.
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title: CFO

BANK: SILICON VALLEY BANK
By	/s/ Win Bear
Name: Win Bear
Title: Deal Team Leader

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Forbearance Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:

ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title: CFO

[SIGNATURE PAGE TO FIRST LOAN MODIFICATION AGREEMENT]

CONSENT AND SECOND LOAN MODIFICATION AGREEMENT

This Consent and Second Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of June 14, 2011, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011 and as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the “Intellectual Property Collateral” as described in a certain Intellectual Property Security Agreement, dated as of March 31, 2011 (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following definitions in Section 13.1 thereof:

““Fidelity Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of the date hereof, by and between Borrower and the “Purchasers” party thereto, in a maximum principal amount equal to Twenty Five Million Dollars ($25,000,000), together with an executed copy of each Fidelity Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“Fidelity Subordination Agreement” is that certain Subordination Agreement, dated as of the date hereof, by and between Bank and the Fidelity Creditors.”

and inserting in lieu thereof the following:

““Fidelity Note Purchase Agreement” is that certain Note Purchase Agreement, dated June 1, 2011, as amended by that certain Amendment No. 1 entered into as of June 14, 2011 by and between Borrower and the “Purchasers” party thereto, in a maximum principal amount equal to Thirty Million Dollars ($30,000,000), together with an executed copy of each Fidelity Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“Fidelity Subordination Agreement” is that certain Subordination Agreement, dated June 1, 2011 by and between Bank and the Fidelity Creditors listed therein, together with any subsequent Subordination Agreement entered into on or after the date hereof, by and between Bank and any Fidelity Creditor or any other “Purchaser” (as such term is defined in the Fidelity Note Purchase Agreement).”

4. ISSUANCE OF ADDITIONAL SUBORDINATED DEBT. The Borrower has requested that the Bank consent to the Borrower receiving proceeds from the issuance of additional unsecured Subordinated Debt to the Fidelity Creditors, as more fully described in the Fidelity Note Purchase Agreement, in substantially the form attached as Exhibit A hereto (such issuance hereafter referred to as the “Transaction”). The Bank has agreed to do so, but only upon and subject to the specific terms and conditions set forth herein.

5. CONSENT. In reliance upon the representations of the Borrower herein, Bank hereby consents to the consummation of the Transaction and waives any Event of Default that may otherwise arise under the Existing Loan Documents solely as a result of the consummation of the Transaction for all purposes under the Existing Loan Documents, subject to each of the Conditions Precedent described in Section 6 hereof. In addition, Bank hereby consents to the amendment to the Note Purchase Agreement, as evidenced by a certain Amendment No. 2 to Subordinated Note and Warrant Purchase Agreement, by and between borrower and the “Purchasers” signatory thereto, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion.

6. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. the Transaction shall be consummated upon terms substantially similar to those contained in the Fidelity Note Purchase Agreement attached at Exhibit A hereto, in each case without any material amendment or modification thereto (it being agreed that any amendment or modification to the Fidelity Note Purchase Agreement attached as Exhibit A hereto which may reasonably be considered materially adverse to the interests of the Bank shall be deemed to be material);

B. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

C. Bank shall have received executed copies of this Loan Modification Agreement, the Fidelity Note Purchase Agreement, as amended, and each Fidelity Subordination Agreement from each Fidelity Creditor, to the extent not previously delivered by such Fidelity Creditor to Bank;

D. After giving effect to the consent granted herein, this Loan Modification Agreement and the Fidelity Note Purchase Agreement, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt; and

E. such other documents and/or agreements as Bank may reasonably request.

7. FEES. Borrower shall reimburse Bank for all legal fees and expenses incurred in connection with this amendment to the Existing Loan Documents.

8. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate, no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in a certain Perfection Certificate, dated as of March 31, 2011, and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remains true and correct in all material respects as of the date hereof.

9. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

10. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

11. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

12. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

13. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

14. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

15. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank

considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

16. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

17. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER: ASPEN AEROGELS, INC.
By	/s/ Donald R. Young
Name:
Title:
BANK: SILICON VALLEY BANK
By	/s/ Win Bear
Name: Win Bear
Title:   Deal Team Leader

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Forbearance Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR: ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ Donald R. Young
Name:
Title:

[SIGNATURE PAGE TO SECOND LOAN MODIFICATION AGREEMENT]

CONSENT AND THIRD LOAN MODIFICATION AGREEMENT

This Consent and Third Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of December 6, 2011, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011 and as further amended by that certain Consent and Second Loan Modification Agreement, dated as of June 14, 2011 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the “Intellectual Property Collateral” as described in a certain Intellectual Property Security Agreement, dated as of March 31, 2011 (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 7.9 (Subordinated Debt) thereof:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement without the prior written consent of Bank.”

and inserting in lieu thereof the following:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement and/or the December 2011 Note Purchase Agreement without the prior written consent of Bank.”

2 The Loan Agreement shall be amended by deleting the following text appearing as Section 8.9 (Subordinated Debt) thereof:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement or the Fidelity Subordination Agreement; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder.”

and inserting in lieu thereof the following:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement, the Fidelity Subordination Agreement or the December 2011 Subordination Agreements; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder and/or the December 2011 Note Purchase Agreement or any December 2011 Note issued thereunder.”

3 The Loan Agreement shall be amended by deleting the following clause (i) from the definition of “Permitted Indebtedness” in Section 13.1 thereof:

“(i) (i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement and (ii) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

and inserting in lieu thereof the following:

“(i) (i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement, (ii) the unsecured Indebtedness of Borrower owed to the December 2011 Creditors pursuant to the December 2011 Note Purchase Agreement, and (iii) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

4 The Loan Agreement shall be amended by inserting the following new definitions in Section 13.1 thereof in their appropriate alphabetical order:

““December 2011 Creditors” is each “Purchaser” from time to time party to the December 2011 Note Purchase Agreement.

“December 2011 Note” and “December 2011 Notes” is each Convertible Note and each Arcapita Note described in and issued pursuant to the December 2011 Note Purchase Agreement.

“December 2011 Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of the date hereof, by and between Borrower and the “Purchasers” party thereto, in a maximum principal amount equal to Twenty Five Million Dollars ($25,000,000), together with an executed copy of each December 2011 Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“December 2011 Subordination Agreement” is each Subordination Agreement, dated as of the date hereof, by and between Bank and each of the December 2011 Creditors.”

4. ISSUANCE OF ADDITIONAL SUBORDINATED DEBT. The Borrower has requested that the Bank consent to the Borrower receiving proceeds from the issuance of additional unsecured Subordinated Debt to the December 2011 Creditors, as more fully described in the December 2011 Note Purchase Agreement, in substantially the form attached as Exhibit A hereto (such issuance hereafter referred to as the “Transaction”). The Bank has agreed to do so, but only upon and subject to the specific terms and conditions set forth herein.

5. CONSENT. In reliance upon the representations of the Borrower herein, Bank hereby consents to the consummation of the Transaction and waives any Event of Default that may otherwise arise under the Existing Loan Documents solely as a result of the consummation of the Transaction for all purposes under the Existing Loan Documents, subject to each of the Conditions Precedent described in Section 6 hereof. In addition, Bank hereby consents to (i) the amendment to the Note Purchase Agreement, as evidenced by a certain Amendment No. 3 to Subordinated Note and Warrant Purchase Agreement, by and between Borrower and the “Purchasers” signatory thereto, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion and (ii) the amendment of the Fidelity Note Purchase Agreement and Fidelity Notes as evidenced by a certain Consent and Amendment No. 2 to Note Purchase Agreement and Notes by and among the Borrower and the Fidelity Creditors, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion.

6. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. the Transaction shall be consummated upon terms substantially similar to those contained in the December 2011 Note Purchase Agreement attached at Exhibit A hereto, in each case without any material amendment or modification thereto (it being agreed that any amendment or modification to the December 2011 Note Purchase Agreement attached as Exhibit A hereto which may reasonably be considered materially adverse to the interests of the Bank shall be deemed to be material);

B. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

C. Bank shall have received executed copies of this Loan Modification Agreement, the December 2011 Note Purchase Agreement, as amended, and each December 2011 Subordination Agreement from each December 2011 Creditor;

D. Bank shall have received a copy of the executed Amendment No. 3 to Subordinated Note and Warrant Purchase Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

E. Bank shall have received from the Fidelity Creditors a copy of the executed Consent and Amendment No. 2 to Note Purchase Agreement and Notes;

F. After giving effect to the consent granted herein, this Loan Modification Agreement and the December 2011 Note Purchase Agreement, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt; and

G. such other documents and/or agreements as Bank may reasonably request.

7. FEES. Borrower shall reimburse Bank for all legal fees and expenses incurred in connection with this amendment to the Existing Loan Documents.

8. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate, no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in a certain Perfection Certificate, dated as of March 31, 2011, and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remains true and correct in all material respects as of the date hereof.

9. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

10. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

11. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

12. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

13. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

14. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

15. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

16. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

17. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John Fairbanks
Name:	John Fairbanks
Title:	CFO

BANK:
SILICON VALLEY BANK
By	/s/ Win Bear
Name:	Win Bear
Title:	Deal Team Leader

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Forbearance Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John Fairbanks
Name:	John Fairbanks
Title:	CFO

[SIGNATURE PAGE TO CONSENT AND THIRD LOAN MODIFICATION AGREEMENT]

Exhibit A

December 2011 Note Purchase Agreement

(See attached.)

A-1

CONSENT AND FOURTH LOAN MODIFICATION AGREEMENT

This Consent and Fourth Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of June 11, 2012, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, and as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2012 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the “Intellectual Property Collateral” as described in a certain Intellectual Property Security Agreement, dated as of March 31, 2011 (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 6.2(a)(vii) (Annual Financial Statements) thereof:

“(vii) as soon as available, and in any event within one hundred eighty (180) days following the end of Borrower’s fiscal year, annual financial statements certified by, and with an unqualified opinion of, independent certified public accountants acceptable to Bank; provided, for Borrower’s fiscal year ended December 31, 2010, such annual financial statements shall be certified by, and with an unqualified opinion of (other than qualified with respect to “going concern”), independent certified public accountants acceptable to Bank;

and inserting in lieu thereof the following:

“(vii) as soon as available, and in any event within one hundred eighty (180) days following the end of Borrower’s fiscal year, annual financial statements certified by, and with an unqualified opinion of, independent certified public accountants acceptable to Bank; provided, for Borrower’s fiscal year ended December 31, 2010, such annual financial statements shall be certified by, and with an unqualified opinion of (other than qualified with respect to “going concern”), independent certified public accountants acceptable to Bank; provided further, for Borrower’s fiscal year ended December 31, 2011, such annual financial statements shall be provided to Bank on or before August 31, 2012;”

2 The Loan Agreement shall be amended by deleting the following text appearing as Section 7.9 (Subordinated Debt) thereof:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement and/or the December 2011 Note Purchase Agreement without the prior written consent of Bank.”

and inserting in lieu thereof the following:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement, the December 2011 Note Purchase Agreement or the June 2012 Note Purchase Agreement without the prior written consent of Bank.”

3 The Loan Agreement shall be amended by deleting the following text appearing as Section 8.9 (Subordinated Debt) thereof:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement, the Fidelity Subordination Agreement or the December 2011 Subordination Agreements; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder and/or the December 2011 Note Purchase Agreement or any December 2011 Note issued thereunder.”

and inserting in lieu thereof the following:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement, the Fidelity Subordination Agreement, the December 2011 Subordination Agreements and/or the June 2012 Subordination Agreements; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder, the December 2011 Note Purchase Agreement or any December 2011 Note issued thereunder and/or the June 2012 Note Purchase Agreement or any June 2012 Note issue thereunder.”

4 The Loan Agreement shall be amended by deleting the following clause (i) from the definition of “Permitted Indebtedness” in Section 13.1 thereof:

“(i) (i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement, (ii) the unsecured Indebtedness of Borrower owed to the December 2011 Creditors pursuant to the December 2011 Note Purchase Agreement, and (iii) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

and inserting in lieu thereof the following:

“(i) (i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement, (ii) the unsecured Indebtedness of Borrower owed to the December 2011 Creditors pursuant to the December 2011 Note Purchase Agreement, (iii) the unsecured Indebtedness of Borrower owed to the June 2012 Creditors pursuant to the June 2012 Note Purchase Agreement, and (iv) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

5 The Loan Agreement shall be amended by inserting the following new definitions in Section 13.1 thereof in their appropriate alphabetical order:

“June 2012 Creditors” is each “Purchaser” from time to time party to the June 2012 Note Purchase Agreement.

“June 2012 Note” and “June 2012 Notes” is each Convertible Note described in and issued pursuant to the June 2012 Note Purchase Agreement.

“June 2012 Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of the date hereof, by and between Borrower and the “Purchasers” party thereto, in a maximum principal amount equal to Fifteen Million Dollars ($15,000,000), together with an executed copy of each June 2012 Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“June 2012 Subordination Agreement” is each Subordination Agreement, dated as of the date hereof, by and between Bank and each of the June 2012 Creditors.”

4. ISSUANCE OF ADDITIONAL SUBORDINATED DEBT. The Borrower has requested that the Bank consent to the Borrower receiving proceeds from the issuance of additional unsecured Subordinated Debt to the June 2012 Creditors, as more fully described in the June 2012 Note Purchase Agreement, in substantially the form attached as Exhibit A hereto (such issuance hereafter referred to as the “Transaction”). The Bank has agreed to do so, but only upon and subject to the specific terms and conditions set forth herein.

5. CONSENT. In reliance upon the representations of the Borrower herein, Bank hereby consents to the consummation of the Transaction and waives any Event of Default that may otherwise arise under the Existing Loan Documents solely as a result of the consummation of the Transaction for all purposes under the Existing Loan Documents, subject to each of the Conditions Precedent described in Section 6 hereof. In addition, Bank hereby consents to (i) the amendment to the Note Purchase Agreement, as evidenced by a certain Consent and Amendment No. 4 to Subordinated Note and Warrant Purchase Agreement, by and between Borrower and the “Purchasers” signatory thereto, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion, (ii) the amendment of the Fidelity Note Purchase Agreement as evidenced by a certain Consent and Amendment No. 3 to Note Purchase Agreement by and among the Borrower and the Fidelity Creditors,

dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion, and (iii) the amendment of the December 2011 Note Purchase Agreement as evidenced by a certain Consent and Amendment No. 2 to Note Purchase Agreement by and among the Borrower and the December 2011 Creditors, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion.

6. WAIVER. Borrower acknowledges that it is currently in default under Sections 8.6 and 8.12 of the Loan Agreement triggered by virtue of the occurrence of a default or event of default under the Note Purchase Agreement, Fidelity Note Purchase Agreement, December 2011 Note Purchase Agreement and the EXIM Loan Documents based upon the Borrower’s failure to deliver to the appropriate party or parties its audited annual financial statements for the fiscal year 2011 within the timeframes provided in the applicable agreement (the “Existing Defaults”). Subject to the execution and delivery of this Loan Modification, Bank hereby waives Borrower’s Existing Defaults. The Borrower hereby acknowledges and agrees that, except as specifically provided herein, nothing in this Section or anywhere in this Loan Modification shall be deemed or otherwise construed as a waiver by the Bank of any of its rights and remedies pursuant to the Existing Loan Documents, applicable law or otherwise.

7. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. the Transaction shall be consummated upon terms substantially similar to those contained in the June 2012 Note Purchase Agreement attached at Exhibit A hereto, in each case without any material amendment or modification thereto (it being agreed that any amendment or modification to the June 2012 Note Purchase Agreement attached as Exhibit A hereto which may reasonably be considered materially adverse to the interests of the Bank shall be deemed to be material);

B. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

C. Bank shall have received executed copies of this Loan Modification Agreement, the June 2012 Note Purchase Agreement, as amended, and each June 2012 Subordination Agreement from each June 2012 Creditor;

D. Bank shall have received a copy of the executed Consent and Amendment No. 4 to Subordinated Note and Warrant Purchase Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

E. Bank shall have received from the Fidelity Creditors a copy of the executed Consent and Amendment No. 3 to Note Purchase Agreement;

F. Bank shall have received from the December 2011 Creditors a copy of the executed Consent and Amendment No. 2 to Note Purchase Agreement;

G. After giving effect to the consent granted herein, this Loan Modification Agreement and the June 2012 Note Purchase Agreement, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt; and

H. such other documents and/or agreements as Bank may reasonably request.

8. FEES. Borrower shall reimburse Bank for all legal fees and expenses incurred in connection with this amendment to the Existing Loan Documents.

9. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of the date hereof and attached hereto as Exhibit B (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof.

10. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

11. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

12. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

13. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

14. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

15. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL

WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

16. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

17. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

18. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John F. Fairbanks
Name:	John Fairbanks
Title:	Chief Financial Officer

BANK:
SILICON VALLEY BANK
By	/s/ Christopher Leary
Name:	Christopher Leary
Title:	VP

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Forbearance Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

[SIGNATURE PAGE TO CONSENT AND FOURTH LOAN MODIFICATION AGREEMENT]

Exhibit A

June 2012 Note Purchase Agreement

(See attached.)

A-1

Exhibit B

Perfection Certificate

(See attached)

B-1

FIFTH LOAN MODIFICATION AGREEMENT

This Fifth Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of September 7, 2012, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2011, and as further amended by that certain Consent and Fourth Loan Modification Agreement dated as of June 11, 2012 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 6.9(a) (Financial Covenants) thereof:

“(a) Liquidity. Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).”

and inserting in lieu thereof the following:

“(a) Liquidity. Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000); provided, however, that the foregoing covenant will not apply during the period commencing on September 7, 2012 through and including September 28, 2012. Bank waives any non-compliance by Borrower with the foregoing covenant that may have occurred prior to September 7, 2012.”

2 The Loan Agreement shall be amended by deleting the following definitions appearing in Section 13.1 (Definitions) thereof:

““Availability Amount” is (a) the lesser of (i) the Revolving Line minus any amounts outstanding under the Export-Import Agreement or (ii) the amount available under the Borrowing Base minus (b) the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), minus (c) the FX Reduction Amount, minus (d) any amounts used for Cash Management Services, and minus (e) the outstanding principal balance of any Advances. The aggregate amount of all Advances (including, without limitation, the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), any outstanding FX Reduction Amount and any amounts used for Cash Management Services) under this Agreement outstanding at any time together with all Credit Extensions made pursuant to the Export-Import Agreement outstanding at any time shall not exceed Ten Million Dollars ($10,000,000).

“Revolving Line” is an Advance or Advances (including, without limitation, Advances made pursuant to the Export-Import Agreement) in an amount under this Agreement and the Export-Import Agreement not to exceed Ten Million Dollars ($10,000,000) at any time.”

and inserting in lieu thereof the following:

““Availability Amount” is (a) the lesser of (i) the Revolving Line minus any amounts outstanding under the Export-Import Agreement or (ii) the amount available under the Borrowing Base minus (b) the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), minus (c) the FX Reduction Amount, minus (d) any amounts used for Cash Management Services, and minus (e) the outstanding principal balance of any Advances. The aggregate amount of all Advances (including, without limitation, the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), any outstanding FX Reduction Amount and any amounts used for Cash Management Services) under this Agreement outstanding at any time together with all Credit Extensions made pursuant to the Export-Import Agreement outstanding at any time shall not exceed Ten Million Dollars ($10,000,000) (Seven Million Dollars ($7,000,000) for the period commencing on September 7, 2012 through and including September 28, 2012).

“Revolving Line” is an Advance or Advances (including, without limitation, Advances made pursuant to the Export-Import Agreement) in an amount under this Agreement and the Export-Import Agreement not to exceed Ten Million Dollars ($10,000,000) (Seven Million Dollars ($7,000,000) for the period commencing on September 7, 2012 through and including September 28, 2012) at any time.”

4. EQUITY RAISE. On or before September 28, 2012, Borrower shall have received not less than Ten Million Dollars ($10,000,000) of net proceeds (less customary fees and expenses reasonably acceptable to Bank) from the issuance of additional equity or convertible debt of Borrower to existing investors of Borrower or other third party investors reasonably acceptable to Bank.

5. FEES. Borrower shall pay to Bank a fully-earned non-refundable loan modification fee equal to Twenty-Five Thousand Dollars ($25,000.00) payable on the date hereof. Borrower shall also reimburse Bank and EXIM Bank for all reasonable legal fees and expenses incurred in connection with the Existing Loan Documents and this Loan Modification Agreement.

6. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of the date hereof and attached hereto as Exhibit B (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof.

7. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

8. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

9. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

10. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

11. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

12. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

13. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

14. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

15. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a scaled instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

BANK:
SILICON VALLEY BANK
By	/s/ signature
Name:	[Name]
Title:	[Title]

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Loan Modification Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

[SIGNATURE PAGE TO FIFTH LOAN MODIFICATION AGREEMENT]

CONSENT AND SIXTH LOAN MODIFICATION AGREEMENT

This Consent and Sixth Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of September 26, 2012, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2011, as further amended by that certain Consent and Fourth Loan Modification Agreement dated as of June 11, 2012, and as further amended by that certain Fifth Loan Modification Agreement dated as of September 7, 2012 (the “Fifth Loan Modification Agreement”) (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following definitions in Section 13.1 thereof:

“June 2012 Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of the date hereof, by and between Borrower and the “Purchasers” party thereto, in a maximum principal amount equal to Fifteen Million Dollars ($15,000,000), together with an executed copy of each June 2012 Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“June 2012 Subordination Agreement” is each Subordination Agreement, dated as of the date hereof, by and between Bank and each of the June 2012 Creditors.

and inserting in lieu thereof the following:

“June 2012 Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of June 11, 2012, as amended by that certain Amendment No. 1 to Note Purchase Agreement dated as of September 26, 2012, by and between Borrower and the “Purchasers” from time to time party thereto, in a maximum principal amount equal to Thirty Five Million One Hundred Thirty Three Thousand Five Hundred Twenty One Dollars and Seventy Nine Cents ($35,133,521.79), together with an executed copy of each June 2012 Note issued thereunder and each other document or agreement executed and/or delivered in connection therewith.

“June 2012 Subordination Agreement” is each Subordination Agreement, dated as of the date of each Closing (as such term is defined in the June 2012 Note Purchase Agreement) under the June 2012 Note Purchase Agreement, by and between Bank and each of the June 2012 Creditors that participates in such Closing.

4. ISSUANCE OF ADDITIONAL SUBORDINATED DEBT. The Borrower has requested that the Bank consent to (i) amending the Note Purchase Agreement, dated as of June 11, 2012, by and between Borrower and the “Purchasers” party thereto (“June 2012 Note Purchase Agreement”) pursuant to that certain Amendment No. 1 to Note Purchase Agreement dated as of the date hereof ( “Amendment No. 1”) and (ii) Borrower receiving proceeds from the issuance of additional unsecured Subordinated Debt to the June 2012 Creditors, as more fully described in the June 2012 Note Purchase Agreement as amended by Amendment No. 1, in substantially the form attached as Exhibit A hereto (such issuance hereafter referred to as the “Transaction”). The Bank has agreed to do so, but only upon and subject to the specific terms and conditions set forth herein.

5. CONSENT. In reliance upon the representations of the Borrower herein, Bank hereby consents to the consummation of the Transaction and waives any Event of Default that may otherwise arise under the Existing Loan Documents solely as a result of the consummation of the Transaction for all purposes under the Existing Loan Documents, subject to each of the Conditions Precedent described in Section 6 hereof. In addition, Bank hereby consents to the amendment to the Note and Purchase Agreement, as evidenced by a certain Consent and Amendment No. 5 to Subordinated Note and Warrant Purchase Agreement, by and between Borrower and the “Purchasers” signatory thereto, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion.

6. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. the Transaction shall be consummated upon terms substantially similar to those contained in the June 2012 Note Purchase Agreement as amended by Amendment No. 1 attached at Exhibit A hereto, in each case without any material amendment or modification thereto (it being agreed that any amendment or modification to the June 2012 Note Purchase Agreement as amended by Amendment No. 1 attached as Exhibit A hereto which may reasonably be considered materially adverse to the interests of the Bank shall be deemed to be material);

B. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

C. Bank shall have received executed copies of this Loan Modification Agreement, Amendment No. 1 and each June 2012 Subordination Agreement from each June 2012 Creditor participating in the Subsequent Closing (as such term is defined in the June 2012 Note Purchase Agreement as amended by Amendment No. 1) to occur on or about the date hereof;

D. Bank shall have received a copy of the executed Consent and Amendment No. 5 to Subordinated Note and Warrant Purchase Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

E. Bank shall have received a copy of the executed Consent, Acknowledgment, Reaffirmation and Amendment of Intercreditor Subordination Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

F. After giving effect to the consent granted herein, this Loan Modification Agreement and Amendment No. 1, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt; and

G. such other documents and/or agreements as Bank may reasonably request.

7. EQUITY RAISE. Notwithstanding the terms of Section 4 of the Fifth Loan Modification Agreement, (i) on or before September 28, 2012, Borrower shall have received not less than Nine Million Five Hundred Nine Thousand Three Hundred Sixty Two Dollars and Seventy Nine Cents ($9,509,362.79) of net proceeds (less customary fees and expenses reasonably acceptable to Bank) from the issuance of additional equity or convertible debt of Borrower to existing investors of Borrower or other third party investors reasonably acceptable to Bank and (ii) on or before October 5, 2012, Borrower shall have received not less than Four Hundred Ninety Thousand Six Hundred Thirty Seven Dollars and Twenty One Cents ($490,637.21) of net proceeds (less customary fees and expenses reasonably acceptable to Bank) from the issuance of additional equity or convertible debt of Borrower to existing investors of Borrower or other third party investors reasonably acceptable to Bank.

8. FEES. Borrower shall reimburse Bank for all legal fees and expenses incurred in connection with this amendment to the Existing Loan Documents.

9. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of June 11, 2012 (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof.

10. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

11. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

12. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

13. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

14. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

15. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

16. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

17. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

18. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title: CFO

BANK:
SILICON VALLEY BANK
By	/s/ Christopher Leary
Name: Christopher Leary
Title: VP

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Loan Modification Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title: CFO

[SIGNATURE PAGE TO CONSENT AND SXITH LOAN MODIFICATION AGREEMENT]

Exhibit A

Amendment No. 1

(See attached.)

A-1

EXECUTION COPY

CONSENT AND SEVENTH LOAN MODIFICATION AGREEMENT

This Consent and Seventh Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of March 28, 2013, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2011, as further amended by that certain Consent and Fourth Loan Modification Agreement dated as of June 11, 2012, as further amended by that certain Fifth Loan Modification Agreement dated as of September 7, 2012 and as further amended by that certain Consent and Sixth Loan Modification Agreement, dated as of September 26, 2012 (the “Sixth Loan Modification Agreement”) (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011 (as may be amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the Intellectual Property Collateral as described in that certain Intellectual Property Security Agreement, by and between Borrower and Bank, dated as of the date hereof (together with any other collateral security granted to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 6.10 thereof:

“6.10 Protection of Intellectual Property Rights. (i) Protect, defend and maintain the validity and enforceability of its material Intellectual Property; (ii) promptly advise Bank in writing of material infringements of its Intellectual Property; and (iii) not allow any Intellectual Property material to Borrower’s business to be abandoned, forfeited or dedicated to the public without Bank’s written consent.”

and inserting in lieu thereof the following:

“6.10 Protection and Registration of Intellectual Property Rights.

(a)     (i) Take such action as, in its reasonable business judgment, it deems necessary to protect, defend and maintain the validity and enforceability of its Material Intellectual Property; (ii) promptly advise Bank in writing of material infringements of its Material Intellectual Property; and (iii) take any action or omit to take any action which would reasonably be expected to result in any Material Intellectual Property being abandoned, forfeited or dedicated to the public without Bank’s written consent.

(b) To the extent not already disclosed in writing to Bank, if Borrower or any Guarantor (i) obtains any Patent, registered Trademark, registered Copyright, registered mask work, or any pending application for any of the foregoing, as owner, or (ii) applies for any Patent or the registration of any Trademark, then Borrower shall (X), with respect to any Copyrights, promptly provide written notice thereof to Bank and shall execute such intellectual property security agreements and other documents and take such other actions as Bank may request in its good faith business judgment to perfect and maintain a first priority perfected security interest (subject only to Permitted Liens) in favor of Bank in such Copyrights, and (Y) with respect to any other Intellectual Property (other than Excluded Intellectual Property), promptly, and in any event together with the delivery of each Compliance Certificate required to be delivered by Borrower to Bank in accordance with Section 6.2(a)(iv) hereof, provide written notice thereof to Bank and execute such intellectual property security agreements and other documents and take such other actions as Bank may request in its good faith business judgment to perfect and maintain a first priority perfected security interest (subject only to Permitted Liens) in favor of Bank in such additional Intellectual Property. If Borrower decides to register any Copyrights or mask works in the United States Copyright Office, Borrower shall: (x) provide Bank with at least fifteen (15) days prior written notice of Borrower’s intent to register such Copyrights or mask works together with a copy of the application it intends to file with the United States Copyright Office (excluding exhibits thereto); (y) execute an intellectual property security agreement and such other documents and take such other actions as Bank may request in its good faith business judgment to perfect and maintain a first priority perfected security interest (subject only to Permitted Liens) in favor of Bank in the Copyrights or mask works intended to be registered with the United States Copyright Office; and (z) record such intellectual property security agreement with the United States Copyright Office contemporaneously with filing the Copyright or mask work application(s) with the United States Copyright Office. Borrower shall promptly (and in any event together with the delivery of each Compliance Certificate required to be delivered by Borrower to Bank in accordance with Section 6.2(a)(iv) hereof), provide to Bank copies of all applications that it files for Patents or for the registration of Trademarks, Copyrights or mask works, and shall promptly provide Bank evidence of the recording of the intellectual property security agreement required for Bank to perfect and maintain a first priority perfected security interest (subject only to Permitted Liens), in such property. The foregoing paragraph shall only be applicable to Intellectual Property registered or otherwise used and/or located in the United States. The Bank acknowledges that the sale, transfer, pledge or mortgage of any Patents is subject to the licenses granted under the Cabot License Agreement.”

2 The Loan Agreement shall be amended by deleting the following text appearing as Section 7.9 thereof:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement, the December 2011 Note Purchase Agreement or the June 2012 Note Purchase Agreement without the prior written consent of Bank.”

and inserting in lieu thereof the following:

“7.9 Subordinated Debt. (a) Make or permit any payment on any Subordinated Debt, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject, or (b) amend any provision in any document relating to the Subordinated Debt which would increase the amount thereof or adversely affect the subordination thereof to Obligations owed to Bank, except as permitted under the terms of the subordination, intercreditor, or other similar agreement to which such Subordinated Debt is subject. Notwithstanding subsection (b) above, Borrower shall not permit any amendment to the Fidelity Note Purchase Agreement, the December 2011 Note Purchase Agreement, the June 2012 Note Purchase Agreement or the March 2013 Note Purchase Agreement without the prior written consent of Bank.”

3 The Loan Agreement shall be amended by deleting the following text appearing as Section 8.9 thereof:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement, the Fidelity Subordination Agreement, the December 2011 Subordination Agreements and/or the June 2012 Subordination Agreements; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder, the December 2011 Note Purchase Agreement or any December 2011 Note issued thereunder and/or the June 2012 Note Purchase Agreement or any June 2012 Note issue thereunder.”

and inserting in lieu thereof the following:

“8.9 Subordinated Debt. (a) Any document, instrument, or agreement evidencing any Subordinated Debt shall for any reason be revoked or invalidated or otherwise cease to be in full force and effect, any Person shall be in breach thereof or contest in any manner the validity or enforceability thereof or deny that it has any further liability or obligation thereunder, or the Obligations shall for any reason be subordinated or shall not have the priority contemplated by this Agreement, the PJC Intercreditor Agreement, the Fidelity Subordination Agreement, the December 2011 Subordination Agreements, the June 2012 Subordination Agreements and/or the March 2013 Subordination Agreements; or (b) (i) any cash prepayment or (ii) acceleration of principal or interest or (iii) the payment of any other Indebtedness of Borrower in each case under the Fidelity Note Purchase Agreement or any Fidelity Note issued thereunder, the December 2011 Note Purchase Agreement or any December 2011 Note issued thereunder, the June 2012 Note Purchase Agreement or any June 2012 Note issued thereunder and/or the March 2013 Note Purchase Agreement or any March 2013 Note issued thereunder.”

4 The Loan Agreement shall be amended by deleting the following text appearing in Section 10 thereof:

“If to Bank: Silicon Valley Bank 275 Grove Street, Suite 2-200 Newton, Massachusetts 02466 Attn: Mr. Dave Rodriguez Fax: (617) 969-4395 Email: drodriguez@svb.com”

and inserting in lieu thereof the following:

“If to Bank: Silicon Valley Bank 275 Grove Street, Suite 2-200 Newton, Massachusetts 02466 Attn: Mr. Chris Leary Fax: (617) 969-4395 Email: cleary@svb.com”

5 The Loan Agreement shall be amended by inserting the following new definitions in Section 13.1 thereof, each in its appropriate alphabetical order:

“Additional 2013 Purchasers” means the “Additional Purchasers”, as such term is defined in the March 2013 Note Purchase Agreement.

“Excluded Intellectual Property” means (i) any “intent-to-use” application for registration of a Trademark filed pursuant to Section 1(b) of the Lanham Act, 15 U.S.C. §1051, prior to the filing of a “Statement of Use” pursuant to Section 1(d) of the Lanham Act or an “Amendment to Allege Use” pursuant to Section 1(c) of the Lanham Act with respect thereto, solely to the extent that, and for so long as, the grant of a security interest or lien therein would impair the validity or enforceability of any registration that issues from such “intent-to-use” application under applicable federal law and (ii) any rights under any license of Intellectual Property if the grant of a security interest therein would be prohibited by the terms of such license, unless (x) the only consequence of breach of such terms would be to avoid or permit any other party to such license to avoid such security interest; or (y) such prohibition is rendered ineffective pursuant to the Uniform Commercial Code or any other applicable law.

“Initial 2013 Closing” is the “Initial Closing”, as such term is defined in the March 2013 Note Purchase Agreement.

“Initial 2013 Purchasers” means the “Initial Purchasers”, as such term is defined in the March 2013 Note Purchase Agreement.

“IP Agreement” is any agreement pursuant to which any Person grants Bank a security interest in such Person’s Intellectual Property as security for the Obligations, including, without limitation, each IP Security Agreement executed by each of Borrower and Guarantor, dated as of the Seventh Loan Modification Effective Date.

“June 2012 Converted Indebtedness” is defined in the definition of March 2013 Note Purchase Agreement.

“March 2013 Additional Purchase Date” is the date the Additional 2013 Purchasers purchase additional March 2013 Notes pursuant to the March 2013 Note Purchase Agreement in an aggregate amount of not less than the result of (i) Ten Million Dollars ($10,000,000) minus (ii) the amount of March 2013 Notes in excess of Five Million Dollars ($5,000,000) (excluding any June 2012 Converted Indebtedness), issued in connection with the Initial 2013 Closing.

“March 2013 Creditors” is each “Initial 2013 Purchaser” and each “Additional 2013 Purchaser” from time to time party to the March 2013 Note Purchase Agreement.

“March 2013 Note” and “March 2013 Notes” is each Convertible Note described in and issued pursuant to the March 2013 Note Purchase Agreement.

“March 2013 Note Purchase Agreement” is that certain Note Purchase Agreement, dated as of the Seventh Loan Modification Agreement, by and among Borrower, the “Initial 2013 Purchasers” party thereto (as of the Seventh Loan Modification Effective Date), and the “Additional 2013 Purchasers” party thereto (after the Seventh Loan Modification Effective Date), in a maximum principal amount for all March 2013 Creditors not to exceed (i) Twenty Two Million Five Hundred Thousand Dollars ($22,500,000), which amount may include up to $7,530,346 in existing Indebtedness to be exchanged for notes originally issued under the June 2012 Note Purchase Agreement (the “June 2102 Converted Indebtedness”), plus (ii) up to Seven Million Five Hundred Thousand Dollars ($7,500,000) in “Call Option Notes” (as defined in the March 2013 Note Purchase Agreement) issued in accordance with the terms of the March 2013 Note Purchase Agreement.

“March 2013 Subordination Agreement” is each Subordination Agreement, dated as of (i) the Seventh Loan Modification Effective Date (with respect to the “Initial 2013 Purchasers”), and (ii) the “March 2013 Additional Purchase Date” (with respect to the “Additional 2013 Purchasers”), in each case by and between Bank and each of the applicable March 2013 Creditors.

“Material Intellectual Property” means any Intellectual Property of Borrower or Guarantor, the absence of which, in the reasonable business judgment of Borrower or Guarantor, would reasonably be expected to result in a Material Adverse Effect. As of the Seventh Loan Modification Effective Date, all Material Intellectual Property is identified as such on Schedule 1 to the Seventh Loan Modification Agreement.

“Seventh Loan Modification Agreement” is that certain Consent and Seventh Loan Modification Agreement between Borrower and Bank dated as of the Seventh Loan Modification Effective Date.

“Seventh Loan Modification Effective Date” is March 28, 2013.

“Subsequent 2013 Closing” is the “Subsequent Closing”, as such term is defined in the March 2013 Note Purchase Agreement.

6 The Loan Agreement shall be amended by deleting the following clause (i) from the definition of “Permitted Indebtedness” in Section 13.1 thereof:

“(i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement, (ii) the unsecured Indebtedness of Borrower owed to the December 2011 Creditors pursuant to the December 2011 Note Purchase Agreement, (iii) the unsecured Indebtedness of Borrower owed to the June 2012 Creditors pursuant to the June 2012 Note Purchase Agreement, and (iv) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

and inserting in lieu thereof the following:

“(i) the unsecured Indebtedness of Borrower owed to the Fidelity Creditors pursuant to the Fidelity Note Purchase Agreement, (ii) the unsecured Indebtedness of Borrower owed to the December 2011 Creditors pursuant to the December 2011 Note Purchase Agreement, (iii) the unsecured Indebtedness of Borrower owed to the June 2012 Creditors pursuant to the June 2012 Note Purchase Agreement, (iv) the unsecured Indebtedness of Borrower owed to the March 2013 Creditors pursuant to the March 2013 Note Purchase Agreement and (v) other unsecured Indebtedness in an aggregate amount not to exceed Two Hundred Fifty Thousand Dollars ($250,000);”

7 The Loan Agreement shall be amended by deleting the following definitions appearing in Section 13.1 thereof:

“Loan Documents” are, collectively, this Agreement, the EXIM Loan Documents, the Perfection Certificates, the Stock Pledge Agreement, the PJC Intercreditor Agreement, any Guaranty Agreement, any Security Agreement, any note, or notes or guaranties executed by Borrower or any Guarantor, and any other present or future agreement between Borrower any Guarantor and/or for the benefit of Bank in connection with this Agreement, all as amended, restated, or otherwise modified.

“Revolving Line Maturity Date” is March 31, 2013 (two (2) years after the Effective Date).

and inserting in lieu thereof the following:

“Loan Documents” are, collectively, this Agreement, the EXIM Loan Documents, the Perfection Certificates, the Stock Pledge Agreement, the PJC Intercreditor Agreement, any Guaranty Agreement, any Security Agreement, any IP Agreement, any note, or notes or guaranties executed by Borrower or any Guarantor, and any other present or future agreement between Borrower any Guarantor and/or for the benefit of Bank in connection with this Agreement, all as amended, restated, or otherwise modified.

“Revolving Line Maturity Date” is May 15, 2013; provided, that in the event the Subsequent 2013 Closing occurs on or before May 15, 2013, pursuant to which Borrower receives gross proceeds from the issuance of additional March 2013 Notes in connection with such Subsequent 2013 Closing in an amount equal to or greater than the result of (i) Ten Million Dollars ($10,000,000) minus (ii) the amount of March 2013 Notes in excess of Five Million Dollars ($5,000,000) (excluding any June 2012 Converted Indebtedness), issued in connection with the Initial 2013 Closing, the “Revolving Line Maturity Date” shall be June 29, 2013.

8 The Loan Agreement shall be amended by deleting Exhibit A in its entirety and replacing it with Exhibit A attached hereto.

4. ISSUANCE OF ADDITIONAL SUBORDINATED DEBT. The Borrower has requested that the Bank consent to the Borrower receiving proceeds from the issuance of additional unsecured Subordinated Debt to the March 2013 Creditors, as more fully described in the March 2013 Note Purchase Agreement, in substantially the form attached as Exhibit A hereto (such issuance hereafter referred to as the “Transaction”). The Bank has agreed to do so, but only upon and subject to (i) Borrower receiving, on or before the Seventh Loan Modification Effective Date, not less than Five Million Dollars ($5,000,000) of gross proceeds from the issuance of the March 2013 Notes pursuant to the March 2013 Note Purchase Agreement; and (ii) the specific terms and conditions set forth herein.

5. CONSENT. In reliance upon the representations of the Borrower herein, Bank hereby consents to the consummation of the Transaction and waives any Event of Default that may otherwise arise under the Existing Loan Documents solely as a result of the consummation of (i) the Transaction; and (ii) the amendments to the Fidelity Note Purchase Agreement, the December 2011 Note Purchase Agreement and the June 2012 Note Purchase Agreement, in each case for all purposes under the Existing Loan Documents and subject to each of the Conditions Precedent described in Section 6 hereof. In addition, Bank hereby consents to the amendment to the Note Purchase Agreement, as evidenced by a certain Consent and Amendment No. 6 to Subordinated Note and Warrant Purchase Agreement, by and between Borrower and the “Purchasers” signatory thereto, dated as of the date hereof, which shall be in form and substance acceptable to Bank, in its reasonable discretion.

6. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. the Transaction shall be consummated upon terms substantially similar to those contained in the March 2013 Note Purchase Agreement attached at Exhibit A hereto, in each case without any material amendment or modification thereto (it being agreed that any amendment or modification to the March 2103 Note Purchase Agreement which may reasonably be considered materially adverse to the interests of the Bank shall be deemed to be material);

B. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

C. Bank shall have received executed copies of this Loan Modification Agreement, the IP Agreement, the March 2013 Note Purchase Agreement and each March 2013 Subordination Agreement from each Initial 2013 Purchaser participating in the Initial 2013 Closing, to occur on or about the date hereof;

D. Bank shall have received a copy of the executed Consent and Amendment No. 6 to Subordinated Note and Warrant Purchase Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

E. Bank shall have received a copy of the executed Consent, Acknowledgment, Amendment and Reaffirmation of Intercreditor and Subordination Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion;

F. Bank shall have received a copy of the executed (i) Consent and Amendment No. 2 to June 2012 Note Purchase Agreement and June 2012 Notes; (ii) Consent and Amendment No. 3 to December 2011 Note Purchase Agreement and December 2011 Notes; and (iii) Consent and Amendment No. 4 to Fidelity Note Purchase Agreement and Fidelity Notes; and

G. After giving effect to the consent granted herein, this Loan Modification Agreement and the March 2013 Note Purchase Agreement, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt.

7. CONDITION SUBSEQUENT.

A. In connection with the Subsequent 2013 Closing, which shall occur on or before May 15, 2013, Borrower shall receive gross proceeds from the issuance of additional March 2013 Notes of not less than the result of (i) Ten Million Dollars ($10,000,000) minus (ii) the amount of March 2013 Notes in excess of Five Million Dollars ($5,000,000) (excluding any June 2012 Converted Indebtedness), issued in connection with the Initial 2013 Closing. Failure of the foregoing to occur as indicated in the foregoing sentence will result in an immediate Event of Default under the Loan Agreement for which no cure or grace period shall apply.

B. On or before the occurrence of the Subsequent 2013 Closing, Borrower shall have delivered to Bank the following, each in form and substance reasonably satisfactory to Bank: (i) an executed consent from Cabot Corporation to the granting by Borrower of a security interest in the Cabot License Agreement and the Borrower’s rights thereunder, and (ii) a written confirmation from Cabot Corporation that upon receipt of the amounts paid or escrowed as provided in Section C below, all sums due to Cabot Corporation under the Cabot License Agreement shall have been paid in full.

C. On or before the occurrence of the Subsequent 2013 Closing, either all remaining sums due from Borrower to Cabot Corporation under the Cabot License Agreement shall be paid in full or an amount sufficient to pay all such remaining sums shall be escrowed pursuant to an escrow agreement in form and substance reasonably satisfactory to Bank for payment to Cabot Corporation as and when due under the Cabot License Agreement.

8. FEES. Borrower shall pay to Bank a fully-earned non-refundable loan modification fee equal to Twelve Thousand Six Hundred Dollars ($12,600.00) payable on the date hereof, consisting of (i) a Ten Thousand Dollar ($10,000.00) EXIM Bank loan modification fee and (ii) a Two Thousand Six Hundred Dollar ($2,600.00) loan modification fee. Borrower shall also reimburse Bank and EXIM Bank for all reasonable legal fees and expenses incurred in connection with the Existing Loan Documents and this Loan Modification Agreement.

9. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of June 11, 2012 (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof.

10. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

11. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

12. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

13. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

14. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

15. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

16. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

17. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

18. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title: Chief Financial Officer

BANK:
SILICON VALLEY BANK
By	/s/ Christopher Leary
Name: Christopher Leary
Title: VP

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of a certain Unconditional Guaranty, dated March 31, 2011 (as amended by that certain First Modification to Security Agreement, dated as of the date hereof, the “Guaranty”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Loan Modification Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title: Chief Financial Officer

[SIGNATURE PAGE TO CONSENT AND SEVENTH LOAN MODIFICATION AGREEMENT]

Exhibit A

EXHIBIT A – COLLATERAL DESCRIPTION

The Collateral consists of all of Borrower’s right, title and interest in and to the following personal property:

All goods, Accounts (including health-care receivables), Equipment, Inventory, contract rights or rights to payment of money, leases, license agreements, franchise agreements, General Intangibles (except as provided below), commercial tort claims, documents, instruments (including any promissory notes), chattel paper (whether tangible or electronic), cash, deposit accounts, fixtures, letters of credit rights (whether or not the letter of credit is evidenced by a writing), securities, and all other investment property, supporting obligations, and financial assets, whether now owned or hereafter acquired, wherever located, but excluding for all purposes any Excluded Intellectual Property; and

all Borrower’s Books relating to the foregoing, and any and all claims, rights and interests in any of the above and all substitutions for, additions, attachments, accessories, accessions and improvements to and replacements, products, proceeds and insurance proceeds of any or all of the foregoing.

Schedule 1

Material Intellectual Property

(As of the Seventh Loan Modification Effective Date.)

Description	Registration/ Application Number		Registration/ Application Date
Aerogel Composite with Fibrous Batting		7,078,359	July 18, 2006
Aerogel Composite with Fibrous Batting		7,504,346	March 17, 2009
Methods to Produce Gel Sheets		7,399,439	July 15, 2008
Methods to Produce Gel Sheets		6,989,123	January 24, 2006
Methods to Produce Gel Sheets		7,780,890	August 24, 2010

Material Trademarks

Description	Registration/ Application Number		Registration/ Application Date
Pyrogel		2137705	February 17, 1998
Aspen Aerogels		3703635	October 27, 2009
Cryogel		3674583	August 25, 2009
Spaceloft		3250920	June 12, 2007

EIGHTH LOAN MODIFICATION AGREEMENT

This Eighth Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of June 28, 2013, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2011, as further amended by that certain Consent and Fourth Loan Modification Agreement dated as of June 11, 2012, as further amended by that certain Fifth Loan Modification Agreement dated as of September 7, 2012 as further amended by that certain Consent and Sixth Loan Modification Agreement, dated as of September 26, 2012 and as further amended by that certain Consent and Seventh Loan Modification Agreement, dated as of March 28, 2013 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011, as amended by that certain Export-Import Bank First Loan Modification Agreement, dated as of March 28, 2013 and as further amended by that certain Export-Import Bank Second Loan Modification Agreement, dated as of the date hereof (as may be further amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the Intellectual Property Collateral as described in that certain Intellectual Property Security Agreement, by and between Borrower and Bank, dated as of March 28, 2013 (together with any other documents granting collateral security to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 2.1.2(a) thereof:

“(a) As part of the Revolving Line and subject to deduction of Reserves, following the Account Transition Period, Bank shall issue or have issued Letters of Credit denominated in Dollars or a Foreign Currency for Borrower’s account. The aggregate Dollar Equivalent amount utilized for the issuance of Letters of Credit shall at all times reduce the amount otherwise available for Advances under the Revolving Line. The aggregate Dollar Equivalent of the face amount of outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve) may not exceed the lesser of (A) Two Million Dollars ($2,000,000), minus (i) the sum of all amounts used for Cash Management Services, and minus (ii) the FX Reduction Amount, or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances (including any amounts used for Cash Management Services), and minus (ii) the FX Reduction Amount.”

1

and inserting in lieu thereof the following:

“(a) As part of the Revolving Line and subject to deduction of Reserves, following the Account Transition Period, Bank shall issue or have issued Letters of Credit denominated in Dollars or a Foreign Currency for Borrower’s account. The aggregate Dollar Equivalent amount utilized for the issuance of Letters of Credit shall at all times reduce the amount otherwise available for Advances under the Revolving Line. The aggregate Dollar Equivalent of the face amount of outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve) may not exceed the lesser of (A) Two Million Five Hundred Thousand Dollars ($2,500,000), minus (i) the sum of all amounts used for Cash Management Services, and minus (ii) the FX Reduction Amount, or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances (including any amounts used for Cash Management Services), and minus (ii) the FX Reduction Amount.”

2 The Loan Agreement shall be amended by deleting the following text appearing as Section 2.1.3 thereof:

“2.1.3 Foreign Exchange Sublimit. As part of the Revolving Line and subject to the deduction of Reserves, following the Account Transition Period, Borrower may enter into foreign exchange contracts with Bank under which Borrower commits to purchase from or sell to Bank a specific amount of Foreign Currency (each, a “FX Forward Contract”) on a specified date (the “Settlement Date”). FX Forward Contracts shall have a Settlement Date of at least one (1) FX Business Day after the contract date. The aggregate amount of FX Forward Contracts at any one time may not exceed ten (10) times the lesser of (A) Two Million Dollars ($2,000,000), minus (i) the sum of all amounts used for Cash Management Services, and minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances (including any amounts used for Cash Management Services), and minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve). The amount otherwise available for Credit Extensions under the Revolving Line shall be reduced by an amount equal to ten percent (10%) of each outstanding FX Forward Contract (the “FX Reduction Amount”). Any amounts needed to fully reimburse Bank for any amounts not paid by Borrower in connection with FX Forward Contracts will be treated as Advances under the Revolving Line and will accrue interest at the interest rate applicable to Advances.”

and inserting in lieu thereof the following:

“2.1.3 Foreign Exchange Sublimit. As part of the Revolving Line and subject to the deduction of Reserves, following the Account Transition Period, Borrower may enter into foreign exchange contracts with Bank under which Borrower commits to purchase from or sell to Bank a specific amount of Foreign Currency (each, a “FX Forward Contract”) on a specified date (the “Settlement Date”). FX Forward Contracts shall have a Settlement Date of at least one (1) FX Business Day after the contract date. The aggregate amount of FX Forward Contracts at any one time may not exceed ten (10) times the lesser of (A) Two Million Five Hundred Thousand Dollars ($2,500,000), minus (i) the sum of all amounts used for Cash Management Services, and minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances (including any amounts used for Cash Management Services), and minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit

2

Reserve). The amount otherwise available for Credit Extensions under the Revolving Line shall be reduced by an amount equal to ten percent (10%) of each outstanding FX Forward Contract (the “FX Reduction Amount”). Any amounts needed to fully reimburse Bank for any amounts not paid by Borrower in connection with FX Forward Contracts will be treated as Advances under the Revolving Line and will accrue interest at the interest rate applicable to Advances.”

3 The Loan Agreement shall be amended by deleting the following text appearing as Section 2.1.4 thereof:

“2.1.4 Cash Management Services Sublimit. Borrower may, following the Account Transition Period, use the Revolving Line for Bank’s cash management services, which may include merchant services, direct deposit of payroll, business credit card, and check cashing services identified in Bank’s various cash management services agreements (collectively, the “Cash Management Services”), in an aggregate amount not to exceed the lesser of (A) Two Million Dollars ($2,000,000), minus (i) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), and minus (ii) the FX Reduction Amount, or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances, minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), and minus (iii) the FX Reduction Amount. Any amounts Bank pays on behalf of Borrower for any Cash Management Services will be treated as Advances under the Revolving Line and will accrue interest at the interest rate applicable to Advances.”

and inserting in lieu thereof the following:

“2.1.4 Cash Management Services Sublimit. Borrower may, following the Account Transition Period, use the Revolving Line for Bank’s cash management services, which may include merchant services, direct deposit of payroll, business credit card, and check cashing services identified in Bank’s various cash management services agreements (collectively, the “Cash Management Services”), in an aggregate amount not to exceed the lesser of (A) Two Million Five Hundred Thousand Dollars ($2,500,000), minus (i) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), and minus (ii) the FX Reduction Amount, or (B) the lesser of Revolving Line or the Borrowing Base, minus (i) the sum of all outstanding principal amounts of any Advances, minus (ii) the Dollar Equivalent of the face amount of any outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit and any Letter of Credit Reserve), and minus (iii) the FX Reduction Amount. Any amounts Bank pays on behalf of Borrower for any Cash Management Services will be treated as Advances under the Revolving Line and will accrue interest at the interest rate applicable to Advances.”

4 The Loan Agreement shall be amended by deleting the following text appearing as Section 2.3(a) thereof:

“(a) Interest Rate; Advances. Subject to Section 2.3(b), the principal amount outstanding under the Revolving Line shall accrue interest at a floating per annum rate equal to Prime Rate plus one percent (1.00%); provided, however, when Borrower is at or above the Liquidity Threshold, the principal amount outstanding under the Revolving Line shall accrue interest at a floating per annum rate equal to the Prime Rate plus one-half percent (0.50%). Such interest shall in any event be payable monthly, in arrears, in accordance with Section 2.3(f) below.”

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and inserting in lieu thereof the following:

“(a) Interest Rate; Advances. Subject to Section 2.3(b), the principal amount outstanding under the Revolving Line shall accrue interest at a floating per annum rate equal to Prime Rate plus one percent (1.00), which interest shall be payable monthly, in arrears, in accordance with Section 2.3(f) below.”

5 The Loan Agreement shall be amended by deleting the following text appearing as Section 6.2(a)(i) thereof:

“(i)     (A) weekly, and (B) upon each request for a Credit Extension, a Transaction Report;”

and inserting in lieu thereof the following:

“(i)     (A) bi-weekly, on the 15^th (or the immediately preceding Business Day if the 15^th is not a Business Day), and the last Business Day of each month, and (B) upon each request for a Credit Extension, a Transaction Report;

Notwithstanding the foregoing, when Borrower is at or above the Liquidity Threshold, Borrower shall only be required to provide Bank with the reports and schedules required pursuant to clause (a)(i)(A) above monthly, within twenty (20) days after the end of each month.”

6 The Loan Agreement shall be amended by deleting the following text appearing as Sections 6.2(a)(vi) and 6.2(a)(vii) thereof:

“(vi) within thirty (30) days prior to the end of each fiscal year of Borrower and as amended or updated, (A) annual operating budgets (including income statements, balance sheets and cash flow statements, by month) for the upcoming fiscal year of Borrower, and (B) annual financial projections for the following fiscal year (on a quarterly basis) as approved by Borrower’s board of directors, together with any related business forecasts used in the preparation of such annual financial projections;

(vii) as soon as available, and in any event within one hundred eighty (180) days following the end of Borrower’s fiscal year, annual financial statements certified by, and with an unqualified opinion of, independent certified public accountants acceptable to Bank; provided, for Borrower’s fiscal year ended December 31, 2010, such annual financial statements shall be certified by, and with an unqualified opinion of (other than qualified with respect to “going concern”), independent certified public accountants acceptable to Bank; provided further, for Borrower’s fiscal year ended December 31, 2011, such annual financial statements shall be provided to Bank on or before August 31, 2012;”

and inserting in lieu thereof the following:

“(vi) within thirty (30) days after the end of each fiscal year of Borrower and as amended or updated, (A) annual operating budgets (including income statements, balance sheets and cash flow statements, by month) for the upcoming fiscal year of Borrower, and (B) annual financial projections for the following fiscal year (on a quarterly basis) as approved by Borrower’s board of directors, together with any related business forecasts used in the preparation of such annual financial projections;

(vii) as soon as available, and in any event within one hundred eighty (180) days following the end of Borrower’s fiscal year, annual financial statements certified by, and with an unqualified opinion of, independent certified public accountants acceptable to Bank; provided, for Borrower’s fiscal year ended December 31, 2010, such annual

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financial statements shall be certified by, and with an unqualified opinion of (other than qualified with respect to “going concern”), independent certified public accountants acceptable to Bank; provided further, that (i) for Borrower’s fiscal year ended December 31, 2011, such annual audited financial statements shall be provided to Bank on or before August 31, 2012 and (ii) for Borrower’s fiscal year ended December 31, 2012, such annual audited financial statements shall be provided to Bank on or before July 31, 2013;”

7 The Loan Agreement shall be amended by deleting the following text appearing at the end of Section 6.2(a) thereof:

“Notwithstanding the foregoing, when Borrower is at or above the Liquidity Threshold, provided no Event of Default has occurred and is continuing, Borrower shall be required to provide Bank with the reports and schedules required pursuant to clause (a)(i)(A) above monthly, within fifteen (15) days after the end of each month.”

8 The Loan Agreement shall be amended by deleting the following text appearing as Section 6.9 thereof:

“6.9 Financial Covenants.

Maintain at all times, to be certified by Borrower as of the last day of each month, unless otherwise noted, on a consolidated basis with respect to Borrower and its Subsidiaries, unless otherwise noted:

(a) Liquidity. Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).

(b) Tangible Net Worth. A Tangible Net Worth of at least Forty Million Dollars ($40,000,000).”

and inserting in lieu thereof the following:

“6.9 Financial Covenants.

(a) Liquidity. Maintain at all times, to be certified by Borrower as of the last day of each month, on a consolidated basis with respect to Borrower and its Subsidiaries, Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).

(b) Adjusted Free Cash Flow. Achieve, as of the last day of each quarterly period listed below, on a consolidated basis with respect to Borrower and its Subsidiaries, an Adjusted Free Cash Flow, of not less than (loss no worse than) the amounts listed below:

Quarterly Period Ending	Minimum Adjusted Free Cash Flow (loss no worse than)
June 30, 2013	($4,400,000)
September 30, 2013 and December 31, 2013	($1,300,000)
March 31, 2014	($850,000)”

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9 The Loan Agreement shall be amended by inserting the following new definitions in Section 13.1 thereof, each in its appropriate alphabetical order:

““Adjusted Free Cash Flow” is, for any period of measurement, the result of (X) (i) Net Income; plus (ii) expenses related to fair market value adjustments on convertible debt; plus (iii) Interest Expense not paid in cash; plus (iv) depreciation and amortization expense; plus (v) provisions for income taxes; plus (vi) non-cash stock compensation expense; plus (vii) other non-cash items reducing Net Income during such period; plus (viii) for the quarterly measurement period ending June 30, 2013, up to Four Hundred Fifty Thousand Dollars ($450,000) for one-time expenses actually incurred by Borrower associated with filings with the SEC and the issuance of convertible debt;

minus

(Y) the sum of (i) non-cash interest income; plus (ii) unfinanced Capital Expenditures; plus (iii) all payments of principal on Indebtedness (including, without limitation, payments made in respect of capital lease obligations but excluding principal payments on the Revolving Line); plus (iv) other non-cash items increasing Net Income during such period.

“Eighth Loan Modification Effective Date” is June 28, 2013.

“Interest Expense” means for any fiscal period, interest expense (whether cash or non-cash) determined in accordance with GAAP for the relevant period ending on such date, including, in any event, interest expense with respect to any Credit Extension and other Indebtedness of Borrower and its Subsidiaries, including, without limitation or duplication, all commissions, discounts, or related amortization and other fees and charges with respect to letters of credit and bankers’ acceptance financing and the net costs associated with interest rate swap, cap, and similar arrangements, and the interest portion of any deferred payment obligation (including leases of all types).

“Net Income” means, as calculated on a consolidated basis for Borrower and its Subsidiaries for any period as at any date of determination, the net profit (or loss), after provision for taxes, of Borrower and its Subsidiaries for such period taken as a single accounting period.

10 The Loan Agreement shall be amended by deleting the following definitions appearing in Section 13.1 thereof:

““Availability Amount” is (a) the lesser of (i) the Revolving Line minus any amounts outstanding under the Export-Import Agreement or (ii) the amount available under the Borrowing Base minus (b) the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), minus (c) the FX Reduction Amount, minus (d) any amounts used for Cash Management Services, and minus (e) the outstanding principal balance of any Advances. The aggregate amount of all Advances (including, without limitation, the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), any outstanding FX Reduction Amount and any amounts used for Cash Management Services) under this Agreement outstanding at any time together with all Credit Extensions made pursuant to the Export-Import Agreement outstanding at any time shall not exceed Ten Million Dollars ($10,000,000) (Seven Million Dollars ($7,000,000) for the period commencing on September 7, 2012 through and including September 28, 2012).

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“Liquidity Threshold” is, on and after the Effective Date, provided no Default or Event of Default has occurred and is continuing, the period (i) commencing on the first (1st) day in which Borrower has, for each consecutive day in the immediately preceding thirty (30) day period, maintained an Adjusted Quick Ratio, as determined by Bank, in its reasonable discretion, in an amount at all times greater than or equal to 1.00:1.00, as determined by Bank, in its sole discretion; and (ii) terminating on the earlier to occur of (A) the occurrence of a Default or an Event of Default; and (B) the first day thereafter in which Borrower fails to maintain an Adjusted Quick Ratio greater than or equal to 1.00:1.00, as determined by Bank, in its reasonable discretion. Thereafter, in order for the Liquidity Threshold to be applicable, Borrower must achieve an Adjusted Quick Ratio in an amount greater than or equal to 1.00:1.00 each consecutive day for thirty (30) consecutive days, as determined by Bank, in its reasonable discretion. Borrower shall give Bank prior-written notice of Borrower’s achievement of the Liquidity Threshold.

“Revolving Line” is an Advance or Advances (including, without limitation, Advances made pursuant to the Export-Import Agreement) in an amount under this Agreement and the Export-Import Agreement not to exceed Ten Million Dollars ($10,000,000) (Seven Million Dollars ($7,000,000) for the period commencing on September 7, 2012 through and including September 28, 2012) at any time.

“Revolving Line Maturity Date” is May 15, 2013; provided, that in the event the Subsequent 2013 Closing occurs on or before May 15, 2013, pursuant to which Borrower receives gross proceeds from the issuance of additional March 2013 Notes in connection with such Subsequent 2013 Closing in an amount equal to or greater than the result of (i) Ten Million Dollars ($10,000,000) minus (ii) the amount of March 2013 Notes in excess of Five Million Dollars ($5,000,000) (excluding any June 2012 Converted Indebtedness), issued in connection with the Initial 2013 Closing, the “Revolving Line Maturity Date” shall be June 29, 2013.”

and inserting in lieu thereof the following:

““Availability Amount” is (a) the lesser of (i) the Revolving Line minus any amounts outstanding under the Export-Import Agreement or (ii) the amount available under the Borrowing Base minus (b) the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), minus (c) the FX Reduction Amount, minus (d) any amounts used for Cash Management Services, and minus (e) the outstanding principal balance of any Advances. The aggregate amount of all Advances (including, without limitation, the Dollar Equivalent amount of all outstanding Letters of Credit (including drawn but unreimbursed Letters of Credit plus an amount equal to the Letter of Credit Reserve), any outstanding FX Reduction Amount and any amounts used for Cash Management Services) under this Agreement outstanding at any time together with all Credit Extensions made pursuant to the Export-Import Agreement outstanding at any time shall not exceed Ten Million Dollars ($10,000,000).

“Liquidity Threshold” is, on and after the Effective Date, provided no Default or Event of Default has occurred and is continuing, the period (i) commencing on the first (1st) day in which Borrower has, for each consecutive day in the immediately preceding thirty (30) day period, maintained unrestricted cash at Bank plus unused Availability Amount, as determined by Bank, in its reasonable discretion, in an amount at all times equal to or greater than Seven Million Dollars ($7,000,000), as determined by Bank, in its reasonable discretion; and (ii) terminating on the earlier to occur of (A) the occurrence of a Default or an Event of Default; and (B) the first day thereafter in which Borrower fails to maintain unrestricted cash at Bank plus unused Availability Amount in an amount equal to or greater than Seven Million Dollars ($7,000,000), as determined by Bank, in its reasonable discretion. Thereafter, in order for the Liquidity Threshold to be applicable,

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Borrower must maintain unrestricted cash at Bank plus unused Availability Amount in an amount equal to or greater than Seven Million Dollars ($7,000,000) each consecutive day for thirty (30) consecutive days, as determined by Bank, in its reasonable discretion. Borrower shall give Bank prior-written notice of Borrower’s anticipated achievement of the Liquidity Threshold.

“Revolving Line” is an Advance or Advances (including, without limitation, Advances made pursuant to the Export-Import Agreement) in an amount under this Agreement and the Export-Import Agreement not to exceed Ten Million Dollars ($10,000,000).

“Revolving Line Maturity Date” is June 27, 2014.”

11 The Loan Agreement shall be amended by deleting the following text appearing as clause (k) in the definition of “Eligible Accounts” in Section 13.1 thereof:

“(k) Accounts subject to contractual arrangements between Borrower and an Account Debtor where payments shall be scheduled or due according to completion or fulfillment requirements where the Account Debtor has a right of offset for damages suffered as a result of Borrower’s failure to perform in accordance with the contract (sometimes called contracts accounts receivable, progress billings, milestone billings, or fulfillment contracts);”

and inserting in lieu thereof the following:

“(k) Accounts subject to contractual arrangements between Borrower and an Account Debtor (other than Subsea 7 and Technip Norge, for which this clause (k) shall not be applicable), where payments shall be scheduled or due according to completion or fulfillment requirements where the Account Debtor has a right of offset for damages suffered as a result of Borrower’s failure to perform in accordance with the contract (sometimes called contracts accounts receivable, progress billings, milestone billings, or fulfillment contracts);”

12 The Loan Agreement shall be amended by deleting Exhibit A in its entirety and replacing it with Exhibit A attached hereto.

4. CONDITIONS PRECEDENT. Borrower hereby agrees that the following representations and warranties shall be true and/or the following documents shall be delivered to the Bank prior to or concurrently with this Loan Modification Agreement, each in form and substance satisfactory to the Bank (collectively, the “Conditions Precedent”):

A. copies, certified by a duly authorized officer of Borrower and Guarantor, to be true and complete as of the date hereof, of each of (i) the governing documents of Borrower and Guarantor, respectively, as in effect on the date hereof (but only to the extent modified since last delivered to the Bank), (ii) the resolutions of Borrower and Guarantor, respectively, authorizing the execution and delivery of this Loan Modification Agreement, the other documents executed in connection herewith and the Borrower’s and Guarantor’s respective performance of all of the transactions contemplated hereby (but only to the extent required since last delivered to Bank), and (iii) an incumbency certificate giving the name and bearing a specimen signature of each individual who shall be so authorized (but only to the extent any signatories have changed since such incumbency certificate was last delivered to Bank);

B. Bank shall have received a copy of the executed Acknowledgment and Reaffirmation of Intercreditor and Subordination Agreement, which shall be in form and substance acceptable to Bank, in its reasonable discretion; and

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C. After giving effect to this Loan Modification Agreement, no Default or Event of Default shall exist and be continuing, including, without limitation, any default under any instrument, agreement or other document evidencing any Subordinated Debt.

5. FEES. Borrower shall pay to Bank a fully-earned non-refundable loan extension fee equal to Eighty Thousand Dollars ($80,000.00) payable on the date hereof. Borrower shall also reimburse Bank and EXIM Bank for all reasonable legal fees and expenses incurred in connection with the Existing Loan Documents and this Loan Modification Agreement.

6. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of June 11, 2012 (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof.

7. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

8. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

9. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

10. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

11. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

12. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the

9

occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

13. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

14. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

15. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

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IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title:   Chief Financial Officer

BANK:
SILICON VALLEY BANK
By	/s/ Christopher Leary
Name: Christopher Leary
Title:   VP

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of (i) a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”) and (ii) a certain Security Agreement, dated as of March 31, 2011 (as amended by that certain First Modification to Security Agreement, dated as of March 28, 2013, the “Security Agreement”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and the Security Agreement and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Loan Modification Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title:   Chief Financial Officer

[SIGNATURE PAGE TO EIGHTH LOAN MODIFICATION AGREEMENT]

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EXHIBIT B

COMPLIANCE CERTIFICATE

TO:         SILICON VALLEY BANK	Date:
FROM:   ASPEN AEROGELS, INC.

The undersigned authorized officer of Aspen Aerogels, Inc. (“Borrower”) certifies that under the terms and conditions of the Loan and Security Agreement between Borrower and Bank (as amended and in effect, the “Agreement”), (1) Borrower is in complete compliance for the period ending                      with all required covenants except as noted below, (2) there are no Events of Default, (3) all representations and warranties in the Agreement are true and correct in all material respects on this date except as noted below; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date, (4) Borrower, and each of its Subsidiaries, has timely filed all required tax returns and reports, and Borrower has timely paid all foreign, federal, state and local taxes, assessments, deposits and contributions owed by Borrower except as otherwise permitted pursuant to the terms of Section 5.9 of the Agreement, and (5) no Liens have been levied or claims made against Borrower or any of its Subsidiaries, if any, relating to unpaid employee payroll or benefits of which Borrower has not previously provided written notification to Bank. Attached are the required documents supporting the certification. The undersigned certifies that these are prepared in accordance with GAAP consistently applied from one period to the next except as explained in an accompanying letter or footnotes. The undersigned acknowledges that no borrowings may be requested at any time or date of determination that Borrower is not in compliance with any of the terms of the Agreement, and that compliance is determined not just at the date this certificate is delivered. Capitalized terms used but not otherwise defined herein shall have the meanings given them in the Agreement.

Please indicate compliance status by circling Yes/No under “Complies” column.

Reporting Covenant	Required	Complies
Monthly financial statements with Compliance Certificate	Monthly within 30 days	Yes    No
Annual financial statement (CPA Audited) + CC	FYE within 180 days (for FYE December 31, 2012, on or before July 31, 2013)	Yes    No
10-Q, 10-K and 8-K	Within 5 days after filing with SEC	Yes    No
A/R & A/P Agings (including EXIM), inventory reports and Borrowing Base Certificate	Monthly within 15 days (quarterly within 15 days if no outstanding Credit Extensions)	Yes    No
Transaction Reports	15th and last Business Day and with each request for a Credit Extension	Yes    No
Invoices for 10% of outstanding balance of EXIM A/R	Within 15 days after the end of each quarter	Yes    No
Projections	FYE within 30 days	Yes    No

Financial Covenant	Required	Actual	Complies
Maintain as indicated:
Liquidity (at all times, certified monthly)	$3,000,000	$_______	Yes    No
Adjusted Free Cash Flow (quarterly)	*	$_______	Yes    No

* See Section 6.9(b) of the Loan and Security Agreement

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The following Intellectual Property was registered after the Effective Date (if no registrations, state “None”)

The following financial covenant analyses and information set forth in Schedule 1 attached hereto are true and accurate as of the date of this Certificate.

The following are the exceptions with respect to the certification above: (If no exceptions exist, state “No exceptions to note.”)

Aspen Aerogels, Inc.	BANK USE ONLY
	Received by:
By:		AUTHORIZED SIGNER
Name:	Date:
Title:	Verified:
		AUTHORIZED SIGNER
	Date:
	Compliance Status:         Yes     No

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Schedule 1 to Compliance Certificate

Financial Covenants of Borrower

In the event of a conflict between this Schedule and the Loan Agreement, the terms of the Loan Agreement shall govern.

Dated:                     

I. Liquidity (Section 6.9(a))

Required: Maintain Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).

Actual:

A.	Borrower’s unrestricted cash at Bank	$
B.	Unused Availability Amount	$
C.	LIQUIDITY (line A plus line B)	$

Is line C equal to or greater than $3,000,000?

             No, not in compliance                                                                                   Yes, in compliance

14

II. Adjusted Free Cash Flow (Section 6.9(b))

Required: Achieve an Adjusted Free Cash Flow, tested quarterly, as of the last day of each quarterly period listed below, of not less than (loss no worse than) the amounts listed below:

Quarterly Period Ending	Minimum Adjusted Free Cash Flow (loss no worse than)
June 30, 2013	($4,400,000)
September 30, 2013 and December 31, 2013	($1,300,000)
March 31, 2014	($850,000)

Actual: all amounts tested on a trailing quarterly basis:

A.	Net Income	$
B.	Interest Expense not paid in cash	$
C.	Depreciation and amortization expense	$
D.	Provisions for income taxes	$
E.	Non-cash stock compensation expense	$
F.	Other non-cash items reducing Net Income during such period	$
G.	Solely for the quarterly period ending June 30, 2013, up to Four Hundred Fifty Thousand Dollars ($450,000) for one-time expenses actually incurred by Borrower associated with filings with the SEC and the issuance of convertible debt	$ $
H.	ADJUSTED NET INCOME (the sum of lines A through G)	$
I.	Non-cash Interest income	$
J.	Unfinanced Capital Expenditures	$
K.	All payments of principal on Indebtedness (including, without limitation, payments made in respect of capital lease obligations but excluding principal payments on the Revolving Line)	$
L.	Other non-cash items increasing Net Income during such period	$
M.	(the sum of lines I through L)	$
N.	ADJUSTED FREE CASH FLOW (line H minus line M)	$

Is line N equal to or greater than (loss no worse than) [                    ]?

             No, not in compliance                                                                                   Yes, in compliance

NINTH LOAN MODIFICATION AGREEMENT

This Ninth Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of November 5, 2013, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement dated as of March 31, 2011, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2011, as further amended by that certain Consent and Fourth Loan Modification Agreement dated as of June 11, 2012, as further amended by that certain Fifth Loan Modification Agreement dated as of September 7, 2012 as further amended by that certain Consent and Sixth Loan Modification Agreement, dated as of September 26, 2012 as further amended by that certain Consent and Seventh Loan Modification Agreement, dated as of March 28, 2013 and as further amended by that certain Eighth Loan Modification Agreement, dated as of June 28, 2013 (as may be amended from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011, as amended by that certain Export-Import Bank First Loan Modification Agreement, dated as of March 28, 2013 and as further amended by that certain Export-Import Bank Second Loan Modification Agreement, dated as of June 28, 2013 (as may be further amended from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the Intellectual Property Collateral as described in that certain Intellectual Property Security Agreement, by and between Borrower and Bank, dated as of March 28, 2013 (together with any other documents granting collateral security to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by inserting the following new text at the end of Section at the end of Section 6.10(b) thereof:

“Notwithstanding anything to the contrary stated herein, (a) no assignment of the Borrower’s rights under the Cabot License Agreement may be made by or on behalf of Bank (or any subsequent assignor) when exercising its rights against the Intellectual Property included in the Collateral without the prior written consent of Cabot Corporation, other than any assignment that is specifically permitted without such consent under Section 9.1 of the Cabot License Agreement and subject to the requirement under Section 9.1 of the Cabot License Agreement that such consent not be unreasonably withheld, and (b) in the event Bank sells or otherwise disposes of Intellectual Property included in the Collateral, unless Cabot Corporation otherwise agrees in writing, all Patents of the Company subject to the Cabot License Agreement will be transferred together with the rights of the Company under the Cabot License Agreement as one package to a single purchaser or assignee (i.e., such Patents will not be sold off piecemeal).”

2 The Loan Agreement shall be amended by deleting Exhibit A in its entirety and replacing it with Exhibit A attached hereto.

1

3 The EXIM Loan Agreement shall be amended by deleting Exhibit A in its entirety and replacing it with Exhibit A attached hereto.

4. FEES. Borrower shall reimburse Bank and EXIM Bank for all reasonable legal fees and expenses incurred in connection with the Existing Loan Documents and this Loan Modification Agreement.

5. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of June 11, 2012 (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof.

6. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

7. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

8. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

9. NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that Borrower has no offsets, defenses, claims, or counterclaims against Bank with respect to the Obligations, or otherwise, and that if Borrower now has, or ever did have, any offsets, defenses, claims, or counterclaims against Bank, whether known or unknown, at law or in equity, all of them are hereby expressly WAIVED and Borrower hereby RELEASES Bank from any liability thereunder.

10. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

11. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

2

12. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

13. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

14. COUNTERSIGNATURE. This Loan Modification Agreement shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

3

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title CFO

BANK:
SILICON VALLEY BANK
By	/s/ Christopher Leary
Name: Christopher Leary
Title: Vice President

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of (i) a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”) and (ii) a certain Security Agreement, dated as of March 31, 2011(as amended by that certain First Modification to Security Agreement, dated as of March 28, 2013, the “Security Agreement”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and the Security Agreement and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Loan Modification Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name: John F. Fairbanks
Title CFO

[SIGNATURE PAGE TO NINTH LOAN MODIFICATION AGREEMENT]

4

Exhibit A

EXHIBIT A – COLLATERAL DESCRIPTION

The Collateral consists of all of Borrower’s right, title and interest in and to the following personal property:

All goods, Accounts (including health-care receivables), Equipment, Inventory, contract rights or rights to payment of money, leases, license agreements, franchise agreements, General Intangibles (except as provided below), commercial tort claims, documents, instruments (including any promissory notes), chattel paper (whether tangible or electronic), cash, deposit accounts, fixtures, letters of credit rights (whether or not the letter of credit is evidenced by a writing), securities, and all other investment property, supporting obligations, and financial assets, whether now owned or hereafter acquired, wherever located, but excluding for all purposes any Excluded Intellectual Property; and

all Borrower’s Books relating to the foregoing, and any and all claims, rights and interests in any of the above and all substitutions for, additions, attachments, accessories, accessions and improvements to and replacements, products, proceeds and insurance proceeds of any or all of the foregoing.

Notwithstanding anything to the contrary stated herein, in the Agreement and/or in the EXIM Loan Agreement, (a) no assignment of the Borrower’s rights under the Cabot License Agreement may be made by or on behalf of Bank and/or EXIM Bank (or any subsequent assignor) when exercising its rights against the Intellectual Property included in the Collateral without the prior written consent of Cabot Corporation, other than any assignment that is specifically permitted without such consent under Section 9.1 of the Cabot License Agreement and subject to the requirement under Section 9.1 of the Cabot License Agreement that such consent not be unreasonably withheld, and (b) in the event Bank and/or EXIM Bank sells or otherwise disposes of Intellectual Property included in the Collateral, unless Cabot Corporation otherwise agrees in writing, all Patents of the Company subject to the Cabot License Agreement will be transferred together with the rights of the Company under the Cabot License Agreement as one package to a single purchaser or assignee (i.e., such Patents will not be sold off piecemeal).

5

TENTH LOAN MODIFICATION AGREEMENT

This Tenth Loan Modification Agreement (this “Loan Modification Agreement”) is entered into as of March 31, 2014, by and between SILICON VALLEY BANK, a California corporation with a loan production office located at 275 Grove Street, Suite 2-200, Newton, Massachusetts 02466 (“Bank”), and ASPEN AEROGELS, INC., a Delaware corporation with offices located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (the “Borrower”).

1. DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other indebtedness and obligations which may be owing by Borrower to Bank, Borrower is indebted to Bank pursuant to a loan arrangement, evidenced by, among other documents, (i) a certain Loan and Security Agreement dated as of March 31, 2011, as amended by that certain Consent and First Loan Modification Agreement dated as of June 1, 2011, as further amended by that certain Consent and Second Loan Modification Agreement dated as of June 14, 2011, as further amended by that certain Consent and Third Loan Modification Agreement dated as of December 6, 2011, as further amended by that certain Consent and Fourth Loan Modification Agreement dated as of June 11, 2012, as further amended by that certain Fifth Loan Modification Agreement dated as of September 7, 2012 as further amended by that certain Consent and Sixth Loan Modification Agreement, dated as of September 26, 2012 as further amended by that certain Consent and Seventh Loan Modification Agreement, dated as of March 28, 2013 as further amended by that certain Eighth Loan Modification Agreement, dated as of June 28, 2013 and as further amended by that certain Ninth Loan Modification Agreement, dated as of November 5, 2013 (as may be further amended, restated, modified or supplemented, from time to time, the “Loan Agreement”) and (ii) a certain Export-Import Bank Loan and Security Agreement, dated as of March 31, 2011, as amended by that certain Export-Import Bank First Loan Modification Agreement, dated as of March 28, 2013, as further amended by that certain Export-Import Bank Second Loan Modification Agreement, dated as of June 28, 2013 and as further amended by that certain Export-Import Bank Third Loan Modification Agreement, dated as of the date hereof (as may be further amended, restated, modified or supplemented from time to time, the “EXIM Loan Agreement”), in each case between Borrower and Bank. Capitalized terms used but not otherwise defined herein shall have the same meaning as in the Loan Agreement.

2. DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by the Collateral as described in the Loan Agreement and EXIM Loan Agreement and the Intellectual Property Collateral as described in that certain Intellectual Property Security Agreement, by and between Borrower and Bank, dated as of March 28, 2013 (together with any other documents granting collateral security to Bank, the “Security Documents”). Hereinafter, the Security Documents, together with all other documents evidencing or securing the Obligations shall be referred to as the “Existing Loan Documents”.

3. DESCRIPTION OF CHANGE IN TERMS.

A. Modifications to Loan Agreement.

1 The Loan Agreement shall be amended by deleting the following text appearing as Section 6.9(b) thereof:

“(b) Adjusted Free Cash Flow. Achieve, as of the last day of each quarterly period listed below, on a consolidated basis with respect to Borrower and its Subsidiaries, an Adjusted Free Cash Flow, of not less than (loss no worse than) the amounts listed below:

Quarterly Period Ending	Minimum Adjusted Free Cash Flow (loss no worse than)
June 30, 2013	($	4,400,000	)
September 30, 2013 and December 31, 2013	($	1,300,000	)
March 31, 2014	($	850,000	)”

1

and inserting in lieu thereof the following:

“(b) Adjusted Free Cash Flow. Achieve, as of the last day of each quarterly period listed below, on a consolidated basis with respect to Borrower and its Subsidiaries, measured as indicated below, an Adjusted Free Cash Flow, of not less than (loss no worse than) the amounts listed below:

Period Ending	Minimum Adjusted Free Cash Flow (loss no worse than)
Trailing three month period ending March 31, 2014	($	2,500,000	)
Trailing four month period ending April 30, 2014	($	2,500,000	)
Trailing five month period ending May 31, 2014	($	2,500,000	)
Trailing six month period ending June 30, 2014	($	2,500,000	)

2 The Loan Agreement shall be amended by deleting the following definition appearing in Section 13.1 thereof:

“Revolving Line Maturity Date” is June 27, 2014.

and inserting in lieu thereof the following:

“Revolving Line Maturity Date” is July 27, 2014.

3 The Loan Agreement shall be amended by deleting Exhibit B in its entirety and replacing it with Exhibit A attached hereto.

4. FEES. Borrower shall pay to Bank a fully-earned non-refundable loan extension fee equal to Twelve Thousand Dollars ($12,000.00) payable on the date hereof. Borrower shall also reimburse Bank and EXIM Bank for all reasonable legal fees and expenses incurred in connection with the Existing Loan Documents and this Loan Modification Agreement.

5. ADDITIONAL COVENANTS: RATIFICATION OF PERFECTION CERTIFICATE. Borrower hereby certifies that, other than as disclosed in the Perfection Certificate (as defined below), no Collateral with a value greater than Fifty Thousand Dollars ($50,000) in the aggregate is in the possession of any third party bailee (such as at a warehouse). In the event that Borrower, after the date hereof, intends to store or otherwise deliver the Collateral with a value in excess of Fifty Thousand Dollars ($50,000) in the aggregate to such a bailee, then Borrower shall first receive, the prior written consent of Bank and such bailee must acknowledge in writing that the bailee is holding such Collateral for the benefit of Bank. Borrower hereby ratifies, confirms and reaffirms, all and singular, the terms and disclosures contained in that certain Perfection Certificate, dated as of March 31, 2011, as amended and restated by that certain Perfection Certificate dated as of June 11, 2012 (the “Perfection Certificate”, which Bank and Borrower hereby acknowledge shall be deemed to be the “Perfection Certificate” for all purposes under the Existing Loan Documents), and acknowledges, confirms and agrees the disclosures and information above

2

Borrower provided to Bank in such Perfection Certificate remain true and correct in all material respects as of the date hereof (except that to the extent the such disclosure or information is expressly stated to have been made as of a specified date, such disclosure or information shall be true and correct as of such specified date).

6. AUTHORIZATION TO FILE. Borrower hereby authorizes Bank to file UCC financing statements without notice to Borrower, with all appropriate jurisdictions, as Bank deems appropriate, in order to further perfect or protect Bank’s interest in the Collateral, including a notice that any disposition of the Collateral, by either the Borrower or any other Person, shall be deemed to violate the rights of the Bank under the Code.

7. CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever necessary to reflect the changes described above.

8. RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and reaffirms all terms and conditions of the Loan Agreement, each other Loan Document and all security or other collateral granted to the Bank, and confirms that the indebtedness secured thereby includes, without limitation, the Obligations.

9. CONTINUING VALIDITY. Borrower understands and agrees that in modifying the existing Obligations, Bank is relying upon Borrower’s representations, warranties, and agreements, as set forth in the Existing Loan Documents. Except as expressly modified pursuant to this Loan Modification Agreement, the terms of the Existing Loan Documents remain unchanged and in full force and effect. Bank’s agreement to modifications to the existing Obligations pursuant to this Loan Modification Agreement in no way shall obligate Bank to make any future modifications to the Obligations. Nothing in this Loan Modification Agreement shall constitute a satisfaction of the Obligations. It is the intention of Bank and Borrower to retain as liable parties all makers of Existing Loan Documents, unless the party is expressly released by Bank in writing. No maker will be released by virtue of this Loan Modification Agreement.

10. RIGHT OF SET-OFF. In consideration of Bank’s agreement to enter into this Loan Modification Agreement, Borrower hereby reaffirms and hereby grants to Bank, a lien, security interest and right of set off as security for all Obligations to Bank, whether now existing or hereafter arising upon and against all deposits, credits, collateral and property, now or hereafter in the possession, custody, safekeeping or control of Bank or any entity under the control of Bank (including a Bank subsidiary) or in transit to any of them. At any time after the occurrence and during the continuance of an Event of Default, without demand or notice, Bank may set off the same or any part thereof and apply the same to any liability or obligation of Borrower even though unmatured and regardless of the adequacy of any other collateral securing the loan. ANY AND ALL RIGHTS TO REQUIRE BANK TO EXERCISE ITS RIGHTS OR REMEDIES WITH RESPECT TO ANY OTHER COLLATERAL WHICH SECURES THE OBLIGATIONS, PRIOR TO EXERCISING ITS RIGHT OF SETOFF WITH RESPECT TO SUCH DEPOSITS, CREDITS OR OTHER PROPERTY OF BORROWER, ARE HEREBY KNOWINGLY, VOLUNTARILY AND IRREVOCABLY WAIVED.

11. CONFIDENTIALITY. In handling any confidential information, Bank shall exercise the same degree of care that it exercises for its own proprietary information, but disclosure of information may be made: (a) to Bank’s Subsidiaries or Affiliates; (b) to prospective transferees or purchasers of any interest in the Credit Extensions (provided, however, Bank shall use commercially reasonable efforts to obtain any prospective transferee’s or purchaser’s agreement to the terms of this provision); (c) as required by law, regulation, subpoena, or other order; (d) to Bank’s regulators or as otherwise required in connection with Bank’s examination or audit; (e) as Bank considers appropriate in exercising remedies under the Loan Documents; and (f) to third-party service providers of Bank so long as such service providers have executed a confidentiality agreement with Bank with terms no less restrictive than those contained herein. Confidential information does not include information that is either: (i) is in the public domain or in Bank’s possession when disclosed to Bank, or becomes part of the public domain after disclosure to Bank; or (ii) is disclosed to Bank by a third party, if Bank does not know that the third party is prohibited from disclosing the information.

Bank may use confidential information for the development of databases, reporting purposes, and market analysis so long as such confidential information is aggregated and anonymized prior to distribution unless otherwise expressly permitted by Borrower. The provisions of the immediately preceding sentence shall survive the termination of the Loan Agreement.

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12. JURISDICTION/VENUE. Section 11 of the Loan Agreement is hereby incorporated by reference in its entirety.

13. COUNTERSIGNATURE. This Loan Modification Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one instrument and shall become effective only when it shall have been executed by Borrower and Bank.

[The remainder of this page is intentionally left blank]

4

IN WITNESS WHEREOF, the parties hereto have caused this Loan Modification Agreement to be executed as a sealed instrument under the laws of the Commonwealth of Massachusetts as of the date first above written.

BORROWER:
ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	CFO
BANK:
SILICON VALLEY BANK
By	/s/ Christopher Leary
Name:	Christopher Leary
Title:	VP

The undersigned ratifies, confirms and reaffirms, all and singular, the terms and conditions of (i) a certain Unconditional Guaranty, dated March 31, 2011 (the “Guaranty”) and (ii) a certain Security Agreement, dated as of March 31, 2011 (as amended by that certain First Modification to Security Agreement, dated as of March 28, 2013, the “Security Agreement”), and each document executed in connection therewith, and acknowledges, confirms and agrees that the Guaranty and the Security Agreement and each document executed in connection therewith shall remain in full force and effect and shall in no way be limited by the execution of this Loan Modification Agreement, or any other documents, instruments and/or agreements executed and/or delivered in connection herewith.

GUARANTOR:
ASPEN AEROGELS RHODE ISLAND LLC
By	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	CFO

[SIGNATURE PAGE TO TENTH LOAN MODIFICATION AGREEMENT]

5

Exhibit A to Tenth Loan Modification Agreement

EXHIBIT B

COMPLIANCE CERTIFICATE

TO:	SILICON VALLEY BANK	Date:
FROM:	ASPEN AEROGELS, INC.

The undersigned authorized officer of Aspen Aerogels, Inc. (“Borrower”) certifies that under the terms and conditions of the Loan and Security Agreement between Borrower and Bank (as amended and in effect, the “Agreement”), (1) Borrower is in complete compliance for the period ending                      with all required covenants except as noted below, (2) there are no Events of Default, (3) all representations and warranties in the Agreement are true and correct in all material respects on this date except as noted below; provided, however, that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof; and provided, further that those representations and warranties expressly referring to a specific date shall be true, accurate and complete in all material respects as of such date, (4) Borrower, and each of its Subsidiaries, has timely filed all required tax returns and reports, and Borrower has timely paid all foreign, federal, state and local taxes, assessments, deposits and contributions owed by Borrower except as otherwise permitted pursuant to the terms of Section 5.9 of the Agreement, and (5) no Liens have been levied or claims made against Borrower or any of its Subsidiaries, if any, relating to unpaid employee payroll or benefits of which Borrower has not previously provided written notification to Bank. Attached are the required documents supporting the certification. The undersigned certifies that these are prepared in accordance with GAAP consistently applied from one period to the next except as explained in an accompanying letter or footnotes. The undersigned acknowledges that no borrowings may be requested at any time or date of determination that Borrower is not in compliance with any of the terms of the Agreement, and that compliance is determined not just at the date this certificate is delivered. Capitalized terms used but not otherwise defined herein shall have the meanings given them in the Agreement.

Please indicate compliance status by circling Yes/No under “Complies” column.

Reporting Covenant	Required	Complies
Monthly financial statements with Compliance Certificate	Monthly within 30 days	Yes  No
Annual financial statement (CPA Audited) + CC	FYE within 180 days (for FYE December 31, 2012, on or before July 31, 2013)	Yes  No
10-Q, 10-K and 8-K	Within 5 days after filing with SEC	Yes  No
A/R & A/P Agings (including EXIM), inventory reports and Borrowing Base Certificate	Monthly within 15 days (quarterly within 15 days if no outstanding Credit Extensions)	Yes  No
Transaction Reports	15th and last Business Day and with each request for a Credit Extension	Yes  No
Invoices for 10% of outstanding balance of EXIM A/R	Within 15 days after the end of each quarter	Yes  No
Projections	FYE within 30 days	Yes  No

Financial Covenant	Required			Actual	Complies
Maintain as indicated:
Liquidity (at all times, certified monthly)	$	3,000,000		$	Yes  No
Adjusted Free Cash Flow (quarterly)			*	$	Yes  No

* See Section 6.9(b) of the Loan and Security Agreement

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The following Intellectual Property was registered after the Effective Date (if no registrations, state “None”)

The following financial covenant analyses and information set forth in Schedule 1 attached hereto are true and accurate as of the date of this Certificate.

The following are the exceptions with respect to the certification above: (If no exceptions exist, state “No exceptions to note.”)

Aspen Aerogels, Inc.	BANK USE ONLY
	Received by:
By:	AUTHORIZED SIGNER
Name:	Date:
Title:
	Verified:
	AUTHORIZED SIGNER
	Date:
	Compliance Status:            Yes            No

7

Schedule 1 to Compliance Certificate

Financial Covenants of Borrower

In the event of a conflict between this Schedule and the Loan Agreement, the terms of the Loan Agreement shall govern.

Dated:                     

I. Liquidity (Section 6.9(a))

Required: Maintain Borrower’s unrestricted cash at Bank plus the unused Availability Amount of at least Three Million Dollars ($3,000,000).

Actual:

A.	Borrower’s unrestricted cash at Bank	$
B.	Unused Availability Amount	$
C.	LIQUIDITY (line A plus line B)	$

Is line C equal to or greater than $3,000,000?

        No, not in compliance             Yes, in compliance

1

II. Adjusted Free Cash Flow (Section 6.9(b))

Required: Achieve, as of the last day of each quarterly period listed below, on a consolidated basis with respect to Borrower and its Subsidiaries, measured as indicated below, an Adjusted Free Cash Flow, of not less than (loss no worse than) the amounts listed below:

Period Ending	Minimum Adjusted Free Cash Flow (loss no worse than)
Trailing three month period ending March 31, 2014	($	2,500,000	)
Trailing four month period ending April 30, 2014	($	2,500,000	)
Trailing five month period ending May 31, 2014	($	2,500,000	)
Trailing six month period ending June 30, 2014	($	2,500,000	)

Actual: all amounts tested as indicated above:

A.	Net Income	$
B.	Interest Expense not paid in cash	$
C.	Depreciation and amortization expense	$
D.	Provisions for income taxes	$
E.	Non-cash stock compensation expense	$
F.	Other non-cash items reducing Net Income during such period	$
G.	Solely for the quarterly period ending June 30, 2013, up to Four Hundred Fifty Thousand Dollars ($450,000) for one-time expenses actually incurred by Borrower associated with filings with the SEC and the issuance of convertible debt		N/A
H.	ADJUSTED NET INCOME (the sum of lines A through G)	$
I.	Non-cash Interest income	$
J.	Unfinanced Capital Expenditures	$
K.	All payments of principal on Indebtedness (including, without limitation, payments made in respect of capital lease obligations but excluding principal payments on the Revolving Line)	$

2

L.	Other non-cash items increasing Net Income during such period	$
M.	(the sum of lines I through L)	$
N.	ADJUSTED FREE CASH FLOW (line H minus line M)	$

Is line N equal to or greater than (loss no worse than) [                    ]?

        No, not in compliance         Yes, in compliance

3

EX-10.5

Exhibit 10.5

THIS INSTRUMENT HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 OR APPLICABLE STATE LAWS AND MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, OFFERED, PLEDGED OR OTHERWISE DISTRIBUTED FOR VALUE UNLESS THERE IS AN EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT AND/OR SUCH LAWS COVERING THIS INSTRUMENT OR THE COMPANY, UPON ITS REQUEST, RECEIVES AN OPINION OF COUNSEL FOR THE HOLDER OF THIS INSTRUMENT STATING THAT SUCH SALE, TRANSFER, ASSIGNMENT, OFFER, PLEDGE OR OTHER DISTRIBUTION FOR VALUE IS EXEMPT FROM THE REGISTRATION AND PROSPECTUS DELIVERY REQUIREMENTS OF SUCH ACT AND APPLICABLE STATE LAWS.

THIS INSTRUMENT IS ALSO SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER AS PROVIDED IN THAT CERTAIN SUBORDINATED NOTE AND WARRANT PURCHASE AGREEMENT DATED AS OF DECEMBER 29, 2010 AMONG THE COMPANY, THE PURCHASERS NAMED ON EXHIBIT A THERETO, AND PJC CAPITAL LLC, AS COLLATERAL AGENT, AS THE SAME MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME (THE “PURCHASE AGREEMENT”).

12% Secured Subordinated Promissory Note

$[___________] December 29, 2010

FOR VALUE RECEIVED, the undersigned, Aspen Aerogels, Inc., a Delaware corporation (“Aspen Aerogels”), hereby promises to pay to [            ], a [            ], or its registered permitted assigns, the principal sum of [            ] ($[            ]), together with interest accrued on the principal balance of this note (including interest compounded and added to such principal balance).

The principal balance of this note shall be due and payable in the manner and at the times provided in the Purchase Agreement (as defined below). Interest on the principal amount of this note from time to time outstanding shall accrue from and after the date hereof at the rate per annum specified in the Purchase Agreement (computed on the basis of a three hundred sixty (360) day year for the actual number of days elapsed in the period during which it accrues). Accrued interest on this note shall be, as specified in the Purchase Agreement, either compounded by adding it to the principal balance of the note at the times provided in the Purchase Agreement or payable in the manner and at the times provided in the Purchase Agreement. In no event, however, shall interest exceed the maximum rate permitted by applicable law.

This note is one of the Notes referred to in that certain Subordinated Note and Warrant Purchase Agreement by and among the purchasers party thereto, Aspen Aerogels dated as of December 29, 2010 (as the same may be amended, supplemented, modified or restated from time to time, the “Purchase Agreement”). Capitalized terms used in this note are defined in the Purchase Agreement, unless otherwise expressly stated herein. This note is entitled to the benefits of the

Purchase Agreement and is subject to all of the agreements, terms and conditions contained therein, all of which are incorporated herein by this reference. Payment of this note is subject to the agreements, terms and conditions contained in any Intercreditor Agreement. This note may be prepaid, in whole or in part, in accordance with the terms and conditions set forth in the Purchase Agreement. This note is guaranteed and secured as provided in the Purchase Agreement and the Security Documents.

As provided in subsection 6.2 of the Purchase Agreement, (a) upon the occurrence of an Event of Default under subsection 6.1(G) or subsection 6.1(H) of the Purchase Agreement, this note, and all amounts payable hereunder in accordance with the terms of the Purchase Agreement, shall immediately become due and payable, without notice of any kind, and (b) upon the occurrence and during the continuance of any other Event of Default under the Purchase Agreement, all or any portion of this note and the amounts payable hereunder in accordance with the terms of the Purchase Agreement shall, at the option of the Majority Holders, immediately become due and payable upon written notice to the Company in accordance with the terms of the Purchase Agreement.

THIS NOTE SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL LAWS OF THE STATE OF NEW YORK, WITHOUT REFERENCE TO PRINCIPLES OF CONFLICTS OF LAW OTHER THAN SECTIONS 5-1401 AND 5-1402 OF THE NEW YORK GENERAL OBLIGATIONS LAW.

Each of the undersigned expressly waives any presentment, demand, protest, notice of default, notice of intention to accelerate, notice of acceleration or notice of any other kind except as expressly provided in the Purchase Agreement.

[Remainder of Page Intentionally Left Blank]

This Secured Subordinated Promissory Note is executed as of the date first written above.

ASPEN AEROGELS, INC.

By:                                                                                                  

Name:                                                                                            

Title:                                                                                              

[Signature Page to $[            ] Note]

EX-10.6

Exhibit 10.6

THIS PROMISSORY NOTE (THIS “NOTE”) AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS. THESE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO DISTRIBUTION OR RESALE, AND MAY NOT BE MORTGAGED, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR, IF REASONABLY REQUESTED, AN OPINION OF COUNSEL SATISFACTORY TO ASPEN AEROGELS, INC. THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT.

THIS NOTE IS ALSO SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER AS PROVIDED IN SECTION 6.4 OF THAT CERTAIN NOTE PURCHSE AGREEMENT, DATED AS OF JUNE 1, 2011, AMONG ASPEN AEROGELS, INC. AND THE PURCHASERS PARTY THERETO (AS MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

THIS NOTE HAS BEEN ISSUED WITH ORIGINAL ISSUE DISCOUNT (“OID”). BEGINNING ON JUNE 10, 2011, THE HOLDER OF THIS NOTE MAY, UPON REQUEST, OBTAIN FROM THE CHIEF FINANCIAL OFFICER OF ASPEN AEROGELS, INC. THIS NOTE’S ISSUE PRICE, ISSUE DATE, AMOUNT OF OID AND YIELD TO MATURITY BY CONTACTING SUCH PERSON AT (508) 691-1111.

THIS NOTE IS ALSO SUBJECT TO (A) THE SUBORDINATION AGREEMENT, DATED AS OF JUNE 1, 2011 BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO AND (B) THE SUBORDINATION AGREEMENT, DATED AS OF JUNE 1, 2011, BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

ASPEN AEROGELS, INC.

SUBORDINATED CONVERTIBLE PROMISSORY NOTE

$[__________] JUNE __, 2011

FOR VALUE RECEIVED, ASPEN AEROGELS, INC., a Delaware corporation (the “Borrower”), hereby promises to pay to [ ] (the “Lender”), the principal sum of $[            ] (the “Principal Amount”), together with interest thereon accruing on and from the date hereof until paid, at an annual rate equal to 8% (which shall be increased to 10% following the occurrence and during the continuance of any Event of Default in accordance with the terms of the Purchase Agreement), compounded annually on December 31 of each year. Interest shall be calculated based on a 360-day year, but in no event shall the rate of interest exceed the maximum rate, if any, allowable under applicable law. The Principal Amount plus accrued interest under this Note up to and including the applicable date is referred to herein as the “Outstanding Balance”.

This subordinated convertible promissory note (this “Note”) is issued by the Borrower pursuant to that certain Note Purchase Agreement dated as of June 1, 2011 (the “Purchase Agreement”), entered into between the Borrower and the persons listed thereto (the “Purchasers”), and is subject to, and Borrower and Lender shall be bound by, all the terms, conditions and provisions of the Purchase Agreement. This Note and the other notes issued pursuant to the Purchase Agreement are hereinafter referred to as the “Notes.” The Lender and the other lenders with respect to the Notes are hereinafter referred to as the “Lenders.” Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Purchase Agreement.

1. Payment. Subject to Section 6 hereof, accrued interest shall be (i) payable in cash at the time Borrower pays the Principal Amount or such other amounts required to be paid under this Note pursuant to Sections 2, 3 or 7 hereof or (ii) converted together with the outstanding Principal Amount under this Note in accordance with Section 6 hereof. No interest shall be payable other than as set forth in the preceding sentence. Unless the indebtedness outstanding under this Note is converted in accordance with Section 6 hereof, all payments on account of principal and interest, or such other amounts required to be paid under this Note, shall be made in lawful money of the United States of America at the principal office of the Lender, or such other place as the holder hereof may from time to time designate in writing to the Borrower.

2. Payment at Maturity; Liquidation Event.

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on the date that is three (3) years after the date hereof (the “Maturity Date”).

(b) Unless this Note is otherwise repaid in accordance with Section 7, upon any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Borrower, and unless this Note has been previously converted as provided herein, the Payoff Amount shall be immediately due and payable to the Lender on the effective date of such liquidation, dissolution or winding up.

3. Prepayment. Borrower may not prepay this Note nor any interest hereon without the consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding.

4. Transfer and Exchange. The holder of this Note may, subject to any restrictions on transfers or assignments in Section 6.4 of the Purchase Agreement (the “Transfer Restrictions”), surrender this Note at the principal office of the Borrower for transfer or exchange. Within a reasonable time after notice to the Borrower from such holder of its intention to make such exchange and without expense to such holder, except for any transfer or similar tax which may be imposed on the transfer or exchange, the Borrower shall issue in exchange therefor, in such denominations of at least $50,000 as shall be specified by such holder, another note or notes for the same aggregate principal amount as the unpaid principal amount of the Note so surrendered, having the same maturity and rate of interest, containing the same provisions and subject to the same terms and conditions as the Note so surrendered. Subject to the Transfer Restrictions, each new Note shall be made payable to such person or persons, or transferees, as the holder of such surrendered Note may designate, and such transfer or exchange shall be made in such a manner that no gain or loss of principal or interest shall result therefrom.

5. New Note. Upon receipt of evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of this Note, and, in the case of any such loss, theft or destruction, upon delivery of a customary indemnity agreement to the Borrower, or, in the case of any such mutilation, upon surrender and cancellation of the Note, as the case may be, the Borrower will issue a new Note of like tenor, in lieu of such lost, stolen, destroyed or mutilated Note.

6. Conversion of Note.

(a) Qualified IPO. In the event of a Qualified IPO (as defined below), but contingent upon the closing of such Qualified IPO, the Outstanding Balance will automatically convert on the closing date of such Qualified IPO into an amount of unregistered shares of Common Stock, par value $0.001 per share, of the Borrower or such other equity securities offered in such public offering (as applicable, the “Common Stock”) equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price (as defined below).

(b) Non-Qualified IPO. In the event of an underwritten public offering of Common Stock other than a Qualified IPO (a “Non-Qualified IPO”), at the election of Lenders holding at least 66 2/3% of the then outstanding principal amount of the Notes, the Outstanding Balance will convert on the closing date of such Non-Qualified IPO into an amount of unregistered shares of Common Stock equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price.

(c) Definitions.

(i) A “Qualified IPO” means the first underwritten public offering of Common Stock, that results in the Common Stock being listed on a United States national securities exchange and (i) that has a minimum gross offering size of at least $60 million or (ii) in which the holders of a majority of the outstanding Series A Preferred Stock and Series B Preferred stock, voting together as a class, elect to convert such preferred stock into shares of Common Stock.

(ii) “Conversion Price” means (A) the price per share of Common Stock paid by purchasers of shares of Common Stock in the applicable underwritten public offering (the “Offering Price”), multiplied by (B) the applicable Conversion Percentage (as defined below).

(iii) “Conversion Percentage” means (A) prior to the first anniversary of the issuance of the Notes (such issuance date of the Notes, the “Issuance Date”), 87.5%, (B) on or after the first anniversary and prior to the second anniversary of the Issuance Date, 75%, and (C) on or after the second anniversary of the Issuance Date, 62.5%.

(d) Conversion Procedures; Other Notices. The Borrower shall give notice of a Qualified IPO, Non-Qualified IPO or Sale of the Borrower (as defined below) (each, a “Triggering Event”) to the Lender as soon as is reasonably practicable prior to the closing of such Triggering Event, but in any case at least (10) business days prior to the closing of any such Triggering Event.

(e) Cash in Lieu of Fractional Shares. No fractional share or interest of Common Stock or scrip representing fractional shares or interests shall be issued upon conversion of this Note. Instead of any fractional shares or interest of Common Stock, which would otherwise be issuable upon conversion of this Note, the Borrower shall pay to the Lender a cash adjustment in an amount equal to the product of such fractional interest multiplied by the Offering Price.

(f) Issuance of Common Stock. Upon the occurrence of any conversion specified in this Section 6, the Lender shall surrender this Note at the office of the Borrower or of its transfer agent against delivery of the applicable amount of Common Stock into which this Note surrendered was convertible on the date on which such conversion occurred. The Borrower shall not be obligated to issue Common Stock issuable upon such conversion unless the Note being converted is either delivered to the Borrower or any such transfer agent, or the Lender provides evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of the Note and the Lender agrees to indemnify and hold harmless the Borrower in respect of any such lost, stolen, destroyed or mutilated Note.

7. Sale of the Borrower.

(a) In the event of a Sale of the Borrower, but, for the avoidance of doubt, contingent upon the closing of such Sale of the Borrower, the Notes shall become due and payable on the closing date of such Sale of the Borrower in cash, in preference to all equity securities of the Borrower, for an amount equal to (i) the Outstanding Balance, divided by (ii) the applicable Conversion Percentage.

(b) “Sale of the Borrower” means (i) a merger or consolidation of the Borrower or any of its Subsidiaries with or into another corporation (with respect to which less than a majority of the outstanding voting power or equity securities of the surviving or consolidated corporation immediately following such event is held by persons or entities who were stockholders of the Borrower immediately prior to such event); (ii) the sale, license, disposition or other transfer of all or substantially all of the properties and assets of the Borrower or any of its Subsidiaries; (iii) any acquisition by any person (or group of affiliated or associated persons) of beneficial ownership of a majority of the equity of the Borrower or of any Subsidiary (whether or not newly-issued shares) in a single transaction or a series of related transactions; or (iv) any other similar change of control of fifty percent (50%) or more of the outstanding voting power of the Borrower or any Subsidiary.

8. Default. This Note shall be subject to the Event of Default provisions set forth in Article VII of the Purchase Agreement.

9. Governing Law. This Note shall be governed by and construed in accordance with the domestic laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflicting provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the laws of any jurisdiction other than the Commonwealth of Massachusetts to be applied. In furtherance of the foregoing, the internal law of the Commonwealth of Massachusetts will control the interpretation and construction of this Note, even if under such jurisdiction’s choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

10. Cancellation of Note. Upon the payment and/or conversion of the Outstanding Balance, or, if applicable, the Payoff Amount, this Note shall be canceled.

11. Collection Expenses. The Borrower further agrees, subject only to any limitation imposed by applicable law, to pay all expenses, including reasonable attorneys’ fees, incurred by the holder of this Note in endeavoring to collect any amounts payable hereunder which are not paid when due.

12. Amendment. Any provision of this Note, except for the principal amount of this Note and the interest rate in connection therewith, may be amended or waived with the written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding.

13. Waiver. Borrower hereby waives presentment, protest, demand for payment, notice of dishonor, and any and all other notices or demands in connection with the deliver, acceptance, performance, default, or enforcement of this Note.

14. Adjustment. All references to share amounts and prices herein shall be equitably adjusted to reflect any stock split, combination, stock dividend or similar event affecting the capital stock of the Borrower.

15. Notice. All notices shall be delivered pursuant to the terms of Section 9.5 of the Purchase Agreement.

16. Lender Actions. Lender may not take any action with respect to this Note, whether to enforce its rights under this Note or otherwise, without the prior written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding.

IN WITNESS WHEREOF, the undersigned has caused this instrument to be executed by its duly authorized officer as of the date first above written.

ASPEN AEROGELS, INC.

By:                                                                                                  

Name:

Title:

NOTE MODIFICATION AGREEMENT

This Note Modification Agreement (this “Agreement”) is entered into as of March 28, 2013 by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and the Purchaser set forth on the signature page hereto, being the Purchaser of one or more Notes issued pursuant to the terms and provisions of the Note Purchase Agreement, dated June 1, 2011, among the Company and the Purchasers party thereto, as amended by that certain Amendment No. 1 to Note Purchase Agreement dated June 14, 2011, that certain Consent and Amendment No. 2 to Note Purchase Agreement dated December 6, 2011, that certain Consent and Amendment No. 3 to Note Purchase Agreement dated June 11, 2012 and that certain Consent and Amendment No. 4 to Note Purchase Agreement dated of even date herewith (as amended, the “NPA”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the NPA.

WHEREAS, the Company and the undersigned Purchaser as a Lender under one or more Notes wish to amend and modify certain terms of such Note or Notes.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. The final paragraph of the legend of each Note is amended by deleting in its entirety and replacing it with the following:

THIS NOTE IS ALSO SUBJECT TO (A) A SUBORDINATION AGREEMENT BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO, DATED AS OF JUNE 1, 2011, OR JUNE 14, 2011, (B) A SUBORDINATION AGREEMENT BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO, DATED AS OF JUNE 1, 2011, OR JUNE 14, 2011, AND (C) THE SUBORDINATION AGREEMENT, DATED AS OF MARCH 28, 2013, BETWEEN THE SENIOR CREDITORS AND JUNIOR CREDITORS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

2. Section 2(a) of each Note is amended by deleting such section in its entirety and replacing it with the following:

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on June 1, 2016 (the “Maturity Date”).

3. Except to the extent amended hereby, all of the terms, provisions and conditions of each Note are hereby ratified and confirmed and shall remain in full force and effect.

4. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Agreement may be executed by facsimile or by electronic or PDF file.

[Signature pages follow]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer

[Note Modification Agreement – June 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

BASF VENTURE CAPITAL GMBH
By:	/s/ Dirk Nachtigal
Name:	Dirk Nachtigal
Title:	Managing Director

[Note Modification Agreement – June 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

FIDELITY ADVISOR SERIES I: FIDELITY ADVISOR DIVIDEND GROWTH FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY ADVISOR SERIES VII: FIDELITY ADVISOR INDUSTRIALS FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY INDUSTRIALS CENTRAL FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY MATERIALS CENTRAL FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Note Modification Agreement – June 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

FIDELITY PURITAN TRUST: FIDELITY PURITAN FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY SECURITIES FUND: FIDELITY DIVIDEND GROWTH FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY SELECT PORTFOLIOS: ENVIRONMENTAL AND ALTERNATIVE ENERGY PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY SELECT PORTFOLIOS: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Note Modification Agreement – June 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

FIDELITY SELECT PORTFOLIOS: MATERIALS
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND III: BALANCED PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND IV: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND IV: MATERIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Note Modification Agreement – June 2011 NPA Notes]

EX-10.7

Exhibit 10.7

THIS PROMISSORY NOTE (THIS “NOTE”) AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS. THESE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO DISTRIBUTION OR RESALE, AND MAY NOT BE MORTGAGED, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR, IF REASONABLY REQUESTED, AN OPINION OF COUNSEL SATISFACTORY TO ASPEN AEROGELS, INC. THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT.

THIS NOTE IS ALSO SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER AS PROVIDED IN SECTION 6.4 OF THAT CERTAIN NOTE PURCHASE AGREEMENT, DATED AS OF DECEMBER 6, 2011, AMONG ASPEN AEROGELS, INC. AND THE PURCHASERS PARTY THERETO (AS MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

THIS NOTE HAS BEEN ISSUED WITH ORIGINAL ISSUE DISCOUNT (“OID”). BEGINNING ON [    ], THE HOLDER OF THIS NOTE MAY, UPON REQUEST, OBTAIN FROM THE CHIEF FINANCIAL OFFICER OF ASPEN AEROGELS, INC. THIS NOTE’S ISSUE PRICE, ISSUE DATE, AMOUNT OF OID AND YIELD TO MATURITY BY CONTACTING SUCH PERSON AT (508) 691-1111.

THIS NOTE IS ALSO SUBJECT TO (A) THE SUBORDINATION AGREEMENT, DATED AS OF [    ] BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO AND (B) THE SUBORDINATION AGREEMENT, DATED AS OF [    ], BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

ASPEN AEROGELS, INC.

FORM OF SUBORDINATED CONVERTIBLE PROMISSORY NOTE

$[                    ] [                    ]

FOR VALUE RECEIVED, ASPEN AEROGELS, INC., a Delaware corporation (the “Borrower”), hereby promises to pay to [    ] (the “Lender”), the principal sum of $[                    ] (the “Principal Amount”), together with interest thereon accruing on and from the date hereof until paid, at an annual rate equal to 8% (which shall be increased to 10% following the occurrence and during the continuance of any Event of Default in accordance with the terms of the Purchase Agreement), compounded annually on December 31 of each year. Interest shall be calculated based on a 360-day year, but in no event shall the rate of interest exceed the maximum rate, if any, allowable under applicable law. The Principal Amount plus accrued interest under this Note up to and including the applicable date is referred to herein as the “Outstanding Balance”.

This subordinated convertible promissory note (this “Note”) is issued by the Borrower pursuant to that certain Note Purchase Agreement dated as of December 6, 2011 (the “Purchase Agreement”), entered into between the Borrower and the persons listed thereto (the “Purchasers”), and is subject to, and Borrower and Lender shall be bound by, all the terms, conditions and provisions of the Purchase Agreement. This Note and the other notes issued pursuant to the Purchase Agreement are hereinafter referred to as the “Notes.” The Lender and the other lenders with respect to the Notes are hereinafter referred to as the “Lenders.” Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Purchase Agreement.

1. Payment. Subject to Section 6 hereof, accrued interest shall be (i) payable in cash at the time Borrower pays the Principal Amount or such other amounts required to be paid under this Note pursuant to Sections 2, 3 or 7 hereof or (ii) converted together with the outstanding Principal Amount under this Note in accordance with Section 6 hereof. No interest shall be payable other than as set forth in the preceding sentence. Unless the indebtedness outstanding under this Note is converted in accordance with Section 6 hereof, all payments on account of principal and interest, or such other amounts required to be paid under this Note, shall be made in lawful money of the United States of America at the principal office of the Lender, or such other place as the holder hereof may from time to time designate in writing to the Borrower.

2. Payment at Maturity; Liquidation Event.

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on the date that is three (3) years after the Initial Closing (the “Maturity Date”).

(b) Unless this Note is otherwise repaid in accordance with Section 7, upon any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Borrower, and unless this Note has been previously converted as provided herein, the Payoff Amount shall be immediately due and payable to the Lender on the effective date of such liquidation, dissolution or winding up.

3. Prepayment. Borrower may not prepay this Note nor any interest hereon without the consent of the Lender.

4. Transfer and Exchange. The holder of this Note may, subject to any restrictions on transfers or assignments in Section 6.4 of the Purchase Agreement (the “Transfer Restrictions”), surrender this Note at the principal office of the Borrower for transfer or exchange. Within a reasonable time after notice to the Borrower from such holder of its intention to make such exchange and without expense to such holder, except for any transfer or similar tax which may be imposed on the transfer or exchange, the Borrower shall issue in exchange therefor, in such denominations of at least $50,000 as shall be specified by such holder, another note or notes for the same aggregate principal amount as the unpaid principal amount of the Note so surrendered, having the same maturity and rate of interest, containing the same provisions and subject to the same terms and conditions as the Note so surrendered. Subject to

the Transfer Restrictions, each new Note shall be made payable to such person or persons, or transferees, as the holder of such surrendered Note may designate, and such transfer or exchange shall be made in such a manner that no gain or loss of principal or interest shall result therefrom.

5. New Note. Upon receipt of evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of this Note, and, in the case of any such loss, theft or destruction, upon delivery of a customary indemnity agreement to the Borrower, or, in the case of any such mutilation, upon surrender and cancellation of the Note, as the case may be, the Borrower will issue a new Note of like tenor, in lieu of such lost, stolen, destroyed or mutilated Note.

6. Conversion of Note.

(a) Qualified IPO. In the event of a Qualified IPO (as defined below), but contingent upon the closing of such Qualified IPO, the Outstanding Balance will automatically convert on the closing date of such Qualified IPO into an amount of unregistered shares of Common Stock, par value $0.001 per share, of the Borrower or such other equity securities offered in such public offering (as applicable, the “Common Stock”) equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price (as defined below).

(b) Non-Qualified IPO. In the event of an underwritten public offering of Common Stock other than a Qualified IPO (a “Non-Qualified IPO”), at the election of Lenders holding at least 66 2/3% of the then outstanding principal amount of the Notes, the Outstanding Balance will convert on the closing date of such Non-Qualified IPO into an amount of unregistered shares of Common Stock equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price.

(c) Definitions.

(i) A “Qualified IPO” means the first underwritten public offering of Common Stock, that results in the Common Stock being listed on a United States national securities exchange and (i) that has a minimum gross offering size of at least $60 million or (ii) in which the holders of a majority of the outstanding Series A Preferred Stock and Series B Preferred stock, voting together as a class, elect to convert such preferred stock into shares of Common Stock.

(ii) “Conversion Price” means (A) the price per share of Common Stock paid by purchasers of shares of Common Stock in the applicable underwritten public offering (the “Offering Price”), multiplied by (B) the applicable Conversion Percentage (as defined below).

(iii) “Conversion Percentage” means (A) prior to the first anniversary of the issuance of the Notes (such issuance date of the Notes, the “Issuance Date”), 87.5%, (B) on or after the first anniversary and prior to the second anniversary of the Issuance Date, 75%, and (C) on or after the second anniversary of the Issuance Date, 62.5%.

(d) Conversion Procedures; Other Notices. The Borrower shall give notice of a Qualified IPO, Non-Qualified IPO or Sale of the Borrower (as defined below) (each, a “Triggering Event”) to the Lender as soon as is reasonably practicable prior to the closing of such Triggering Event, but in any case at least (10) business days prior to the closing of any such Triggering Event.

(e) Cash in Lieu of Fractional Shares. No fractional share or interest of Common Stock or scrip representing fractional shares or interests shall be issued upon conversion of this Note. Instead of any fractional shares or interest of Common Stock, which would otherwise be issuable upon conversion of this Note, the Borrower shall pay to the Lender a cash adjustment in an amount equal to the product of such fractional interest multiplied by the Offering Price.

(f) Issuance of Common Stock. Upon the occurrence of any conversion specified in this Section 6, the Lender shall surrender this Note at the office of the Borrower or of its transfer agent against delivery of the applicable amount of Common Stock into which this Note surrendered was convertible on the date on which such conversion occurred. The Borrower shall not be obligated to issue Common Stock issuable upon such conversion unless the Note being converted is either delivered to the Borrower or any such transfer agent, or the Lender provides evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of the Note and the Lender agrees to indemnify and hold harmless the Borrower in respect of any such lost, stolen, destroyed or mutilated Note.

7. Sale of the Borrower.

(a) In the event of a Sale of the Borrower, but, for the avoidance of doubt, contingent upon the closing of such Sale of the Borrower, the Notes shall become due and payable on the closing date of such Sale of the Borrower in cash, in preference to all equity securities of the Borrower, for an amount equal to (i) the Outstanding Balance, divided by (ii) the applicable Conversion Percentage.

(b) “Sale of the Borrower” means (i) a merger or consolidation of the Borrower or any of its Subsidiaries with or into another corporation (with respect to which less than a majority of the outstanding voting power or equity securities of the surviving or consolidated corporation immediately following such event is held by persons or entities who were stockholders of the Borrower immediately prior to such event); (ii) the sale, license, disposition or other transfer of all or substantially all of the properties and assets of the Borrower or any of its Subsidiaries; (iii) any acquisition by any person (or group of affiliated or associated persons) of beneficial ownership of a majority of the equity of the Borrower or of any Subsidiary (whether or not newly-issued shares) in a single transaction or a series of related transactions; or (iv) any other similar change of control of fifty percent (50%) or more of the outstanding voting power of the Borrower or any Subsidiary.

8. Default. This Note shall be subject to the Event of Default provisions set forth in Article VII of the Purchase Agreement.

9. Governing Law. This Note shall be governed by and construed in accordance with the domestic laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflicting provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the laws of any jurisdiction other than the Commonwealth of Massachusetts to be applied. In furtherance of the foregoing, the internal law of the Commonwealth of Massachusetts will control the interpretation and construction of this Note, even if under such jurisdiction’s choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

10. Cancellation of Note. Upon the payment and/or conversion of the Outstanding Balance, or, if applicable, the Payoff Amount, this Note shall be canceled.

11. Collection Expenses. The Borrower further agrees, subject only to any limitation imposed by applicable law, to pay all expenses, including reasonable attorneys’ fees, incurred by the holder of this Note in endeavoring to collect any amounts payable hereunder which are not paid when due.

12. Amendment. Any provision of this Note, except for (i) the principal amount of this Note, (ii) the interest rate in connection therewith, (iii) Section 2, (iv) Section 3 and (v) Section 6, may be amended or waived with the written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding so long as such amendment or waiver does not materially adversely affect the rights and obligations of a Lender in a manner different from the other Lenders.

13. Waiver. Borrower hereby waives presentment, protest, demand for payment, notice of dishonor, and any and all other notices or demands in connection with the deliver, acceptance, performance, default, or enforcement of this Note.

14. Adjustment. All references to share amounts and prices herein shall be equitably adjusted to reflect any stock split, combination, stock dividend or similar event affecting the capital stock of the Borrower.

15. Notice. All notices shall be delivered pursuant to the terms of Section 9.5 of the Purchase Agreement.

16. Lender Actions. Lender may not take any action with respect to this Note, whether to enforce its rights under this Note or otherwise, without the prior written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding.

IN WITNESS WHEREOF, the undersigned has caused this instrument to be executed by its duly authorized officer as of the date first above written.

ASPEN AEROGELS, INC.
By:
Name:	John F. Fairbanks
Title:	Vice President and CFO

[Signature Page to Subordinated Convertible Promissory Note]

NOTE MODIFICATION AGREEMENT

This Note Modification Agreement (this “Agreement”) is entered into as of March 28, 2013 by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and the Purchaser set forth on the signature page hereto, being the Purchaser of one or more Notes issued pursuant to the terms and provisions of the Note Purchase Agreement, dated December 6, 2011, among the Company and the Purchasers party thereto, as amended by that certain Amendment No. 1 to Note Purchase Agreement dated March 1, 2012, that certain Consent and Amendment No. 2 to Note Purchase Agreement dated June 11, 2012, and that certain Consent and Amendment No. 3 to Note Purchase Agreement dated of even date herewith (as amended, the “NPA”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the NPA.

WHEREAS, the Company and the undersigned Purchaser as a Lender under one or more Notes wish to amend and modify certain terms of such Note or Notes.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. The final paragraph of the legend of each Note is amended by deleting in its entirety and replacing it with the following:

THIS NOTE IS ALSO SUBJECT TO (A) A SUBORDINATION AGREEMENT BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO, DATED AS OF DECEMBER 6, 2011, OR MARCH 1, 2012, (B) A SUBORDINATION AGREEMENT BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO, DATED AS OF DECEMBER 6, 2011, OR MARCH 1, 2012, AND (C) THE SUBORDINATION AGREEMENT, DATED AS OF MARCH 28, 2013, BETWEEN THE SENIOR CREDITORS AND JUNIOR CREDITORS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

2. Section 2(a) of each Note is amended by deleting such section in its entirety and replacing it with the following:

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on December 6, 2016 (the “Maturity Date”).

3. Except to the extent amended hereby, all of the terms, provisions and conditions of each Note are hereby ratified and confirmed and shall remain in full force and effect.

4. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Agreement may be executed by facsimile or by electronic or PDF file.

[Signature pages follow]

[Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	CFO

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

GKFF VENTURES I, LLC
(f/k/a Argonaut Ventures I, LLC)
By:	/s/ Robert Thomas
Name:	Robert Thomas
Title:	Manager and Vice President

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

RESERVOIR CAPITAL MASTER FUND, L.P.
By:	Reservoir Capital Group, L.L.C.
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer
RESERVOIR CAPITAL MASTER FUND, L.P.
By:	RCP GP, LLC
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

ARCAPITA VENTURES I LIMITED
By:	/s/ John Huntz
Name:	John Huntz
Title:	Executive Director

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

TENAYA CAPITAL IV, L.P.
By: Tenaya Capital IV Annex GP, LLC, its General Partner
By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact
TENAYA CAPITAL IV-C, L.P.
By:	Tenaya Capital IV GP, LP, its General Partner
By:	Tenaya Capital IV GP, LLC, its General Partner
By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact
TENAYA CAPITAL IV-P, L.P.
By:	Tenaya Capital IV GP, LP, its General Partner
By:	Tenaya Capital IV GP, LLC, its General Partner
By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

BASF VENTURE CAPITAL GMBH
By:	/s/ Dirk Nachtigal
Name:	Dirk Nachtigal
Title:	Managing Director

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

LEHMAN BROTHERS OFFSHORE PARTNERSHIP ACCOUNT 2000/2001, L.P.
By:	Lehman Brothers Offshore Partners Ltd
Its:	General Partner
By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory
LEHMAN BROTHERS PARTNERSHIP ACCOUNT 2000/2001, L.P.
By:	LBI Group Inc.
Its:	General Partner
By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory
LEHMAN BROTHERS VENTURE CAPITAL PARTNERS II, L.P.
By:	Venture Associates II GP LP
Its:	General Partner
By:	Lehman Brothers Venture Associates II LLC
Its:	General Partner
By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

ROCKPORT CAPITAL PARTNERS, L.P.
By:	RockPort Capital, L.L.C.
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner
ROCKPORT CAPITAL PARTNERS II, L.P.
By:	RockPort Capital II, L.L.C.
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner
RP CO-INVESTMENT FUND I, L.P.
By:	RP Co-Investments Fund I, GP, LLC
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

FIDELITY ADVISOR SERIES VII: FIDELITY ADVISOR INDUSTRIALS FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY PURITAN TRUST: FIDELITY PURITAN FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY SELECT PORTFOLIOS: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

VARIABLE INSURANCE PRODUCTS FUND IV: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

MOUNT HOPE ASPEN, LLC
By:	/s/ Brian Scanlan
Name:	Brian Scanlan
Title:	Manager

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

NOTE MODIFICATION AGREEMENT

This Note Modification Agreement (this “Agreement”) is entered into as of May 6, 2013, by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and the Purchaser set forth on the signature page hereto, being the Purchaser of one or more Notes issued pursuant to the terms and provisions of the Note Purchase Agreement, dated December 6, 2011, among the Company and the Purchasers party thereto, as amended by that certain Amendment No. 1 to Note Purchase Agreement dated March 1, 2012, that certain Consent and Amendment No. 2 to Note Purchase Agreement dated June 11, 2012, and that certain Consent and Amendment No. 3 to Note Purchase Agreement dated March 28, 2013 (as amended, the “NPA”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the NPA.

WHEREAS, the Company and the undersigned Purchaser as a Lender under one or more Notes wish to amend and modify certain terms of such Note or Notes.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. The final paragraph of the legend of each Note is amended by deleting in its entirety and replacing it with the following:

THIS NOTE IS ALSO SUBJECT TO (A) A SUBORDINATION AGREEMENT BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO, DATED AS OF DECEMBER 6, 2011, OR MARCH 1, 2012, (B) A SUBORDINATION AGREEMENT BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO, DATED AS OF DECEMBER 6, 2011, OR MARCH 1, 2012, AND (C) THE SUBORDINATION AGREEMENT, DATED AS OF MAY 6, 2013, BETWEEN THE SENIOR CREDITORS AND JUNIOR CREDITORS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

2. Section 2(a) of each Note is amended by deleting such section in its entirety and replacing it with the following:

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on December 6, 2016 (the “Maturity Date”).

3. Except to the extent amended hereby, all of the terms, provisions and conditions of each Note are hereby ratified and confirmed and shall remain in full force and effect.

4. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Agreement may be executed by facsimile or by electronic or PDF file.

[Signature pages follow]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Vice President and CFO

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

NICHIAS CORPORATION
By:	/s/ Kunihiko Yano
Name:	Kunihiko Yano
Title:	President and Chief Executive Officer
	NICHIAS Corporation

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Thomas L. Cunningham Trust
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Susan Zimmerman
	Name:
	Title:	Trustee
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Charles C. Cunningham, Jr. Trust 1990
Name:	Charles C. Cunningham, Jr.
Title:	Trustee
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Melissa D. Spangler
Name:	Melissa D. Spangler
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Auchincloss & Ong Family Trust (d/d 5/5/98)
Name of Entity (Print or Type)
By:	/s/ Belita Ong
	Name of Entity (Print or Type): Belita Ong
	Its: Trustee
(Complete above if another entity signs for entity listed above)
By:	/s/ James Gordon Auchincloss
	Name:	James Gordon Auchincloss
	Title:	Trustee
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Jonathan F.P. Rose
Name:	Jonathan F.P. Rose
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ John Huntz
Name:	John Huntz
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ P. Ramsay Battin
Name:	P. Ramsay Battin
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Name of Entity (Print or Type)
By:	Jamie Trust
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Jamie McCourt, Trustee
	Name:	Jamie McCourt
	Title:	Trustee
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	Linnea J. Geiss
Name:
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Linnea J. Geiss
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Donald R. Young
Name:	Donald R. Young
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Edward Lamont
Name:	Edward Lamont
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Aerogel Korea
Name of Entity (Print or Type)
By:	Aerogel Korea
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Joo Young Park
	Name:	Joo Young Park
	Title:	CEO
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Dalsuk Youn
Name:	Dalsuk Youn
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

			INDIVIDUAL:
			By:
			Name:
			Title:
			ENTITY:
FORTE VENTURES L.P.
By:	Forte Capital Management L.L.C., its general partner
		By:	Hawkins Ventures, Inc., as Manager
			By:	/s/ Thomas N. Hawkins
				Thomas N. Hawkins, President & CEO

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Jae S. Lee
Name:	Jae S. Lee
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	Junho Lee
Name:
Title:
ENTITY:
Junhoo Lee
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Junho Lee
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Maricamp LLC
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ John A. Galat
	Name:	John A. Galat
	Title:	Owner
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Protos, L.L.C.
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Thomas H. Grant
	Name:	Thomas H. Grant
	Title:	Manager
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Richard M.C. Glenn III
Name:	Richard M.C. Glenn III
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Soo Young & Myung Sook Chung
Name:	Soo Young & Myung Sook Chung
Title:	Joint tenants by entireties
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – December 2011 NPA Notes]

EX-10.8

Exhibit 10.8

THIS PROMISSORY NOTE (THIS “NOTE”) AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS. THESE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO DISTRIBUTION OR RESALE, AND MAY NOT BE MORTGAGED, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR, IF REASONABLY REQUESTED, AN OPINION OF COUNSEL SATISFACTORY TO ASPEN AEROGELS, INC. THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT.

THIS NOTE IS ALSO SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER AS PROVIDED IN SECTION 6.4 OF THAT CERTAIN NOTE PURCHASE AGREEMENT, DATED AS OF JUNE 11, 2012 [    ], AMONG ASPEN AEROGELS, INC. AND THE PURCHASERS PARTY THERETO (AS MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

THIS NOTE HAS BEEN ISSUED WITH ORIGINAL ISSUE DISCOUNT (“OID”). BEGINNING ON [    ], THE HOLDER OF THIS NOTE MAY, UPON REQUEST, OBTAIN FROM THE CHIEF FINANCIAL OFFICER OF ASPEN AEROGELS, INC. THIS NOTE’S ISSUE PRICE, ISSUE DATE, AMOUNT OF OID AND YIELD TO MATURITY BY CONTACTING SUCH PERSON AT (508) 691-1111.

THIS NOTE IS ALSO SUBJECT TO (A) THE SUBORDINATION AGREEMENT, DATED AS OF [    ] BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO AND (B) THE SUBORDINATION AGREEMENT, DATED AS OF [    ], BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

ASPEN AEROGELS, INC.

FORM OF SUBORDINATED CONVERTIBLE PROMISSORY NOTE

$[                    ] [                     ]

FOR VALUE RECEIVED, ASPEN AEROGELS, INC., a Delaware corporation (the “Borrower”), hereby promises to pay to [    ] (the “Lender”), the principal sum of $[                    ] (the “Principal Amount”), together with interest thereon accruing on and from the date hereof until paid, at an annual rate equal to 8% (which shall be increased to 10% following the occurrence and during the continuance of any Event of Default in accordance with the terms of the Purchase Agreement), compounded annually on December 31 of each year. Interest shall be calculated based on a 360-day year, but in no event shall the rate of interest exceed the maximum rate, if any, allowable under applicable law. The Principal Amount plus accrued interest under this Note up to and including the applicable date is referred to herein as the “Outstanding Balance”.

This subordinated convertible promissory note (this “Note”) is issued by the Borrower pursuant to that certain Note Purchase Agreement dated as of June 11, 2012 [    ] (the “Purchase Agreement”), entered into between the Borrower and the persons listed thereto (the “Purchasers”), and is subject to, and Borrower and Lender shall be bound by, all the terms, conditions and provisions of the Purchase Agreement. This Note and the other notes issued pursuant to the Purchase Agreement are hereinafter referred to as the “Notes.” The Lender and the other lenders with respect to the Notes are hereinafter referred to as the “Lenders.” Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Purchase Agreement.

1. Payment. Subject to Section 6 hereof, accrued interest shall be (i) payable in cash at the time Borrower pays the Principal Amount or such other amounts required to be paid under this Note pursuant to Sections 2, 3 or 7 hereof or (ii) converted together with the outstanding Principal Amount under this Note in accordance with Section 6 hereof. No interest shall be payable other than as set forth in the preceding sentence. Unless the indebtedness outstanding under this Note is converted in accordance with Section 6 hereof, all payments on account of principal and interest, or such other amounts required to be paid under this Note, shall be made in lawful money of the United States of America at the principal office of the Lender, or such other place as the holder hereof may from time to time designate in writing to the Borrower.

2. Payment at Maturity; Liquidation Event.

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on December 6, 2014 (the “Maturity Date”).

(b) Unless this Note is otherwise repaid in accordance with Section 7, upon any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Borrower, and unless this Note has been previously converted as provided herein, the Payoff Amount shall be immediately due and payable to the Lender on the effective date of such liquidation, dissolution or winding up.

3. Prepayment. Borrower may not prepay this Note nor any interest hereon without the consent of the Lender.

4. Transfer and Exchange. The holder of this Note may, subject to any restrictions on transfers or assignments in Section 6.4 of the Purchase Agreement (the “Transfer Restrictions”), surrender this Note at the principal office of the Borrower for transfer or exchange. Within a reasonable time after notice to the Borrower from such holder of its intention to make such exchange and without expense to such holder, except for any transfer or similar tax which may be imposed on the transfer or exchange, the Borrower shall issue in exchange therefor, in such denominations of at least $50,000 as shall be specified by such holder, another note or notes for the same aggregate principal amount as the unpaid principal amount of the Note so surrendered, having the same maturity and rate of interest, containing the same provisions and subject to the same terms and conditions as the Note so surrendered. Subject to

2

the Transfer Restrictions, each new Note shall be made payable to such person or persons, or transferees, as the holder of such surrendered Note may designate, and such transfer or exchange shall be made in such a manner that no gain or loss of principal or interest shall result therefrom.

5. New Note. Upon receipt of evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of this Note, and, in the case of any such loss, theft or destruction, upon delivery of a customary indemnity agreement to the Borrower, or, in the case of any such mutilation, upon surrender and cancellation of the Note, as the case may be, the Borrower will issue a new Note of like tenor, in lieu of such lost, stolen, destroyed or mutilated Note.

6. Conversion of Note.

(a) Qualified IPO. In the event of a Qualified IPO (as defined below), but contingent upon the closing of such Qualified IPO, the Outstanding Balance will automatically convert on the closing date of such Qualified IPO into an amount of unregistered shares of Common Stock, par value $0.001 per share, of the Borrower or such other equity securities offered in such public offering (as applicable, the “Common Stock”) equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price (as defined below).

(b) Non-Qualified IPO. In the event of an underwritten public offering of Common Stock other than a Qualified IPO (a “Non-Qualified IPO”), at the election of Lenders holding at least 66 2/3% of the then outstanding principal amount of the Notes, the Outstanding Balance will convert on the closing date of such Non-Qualified IPO into an amount of unregistered shares of Common Stock equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price.

(c) Definitions.

(i) A “Qualified IPO” means the first underwritten public offering of Common Stock, that results in the Common Stock being listed on a United States national securities exchange and (i) that has a minimum gross offering size of at least $60 million or (ii) in which the holders of a majority of the outstanding Series A Preferred Stock and Series B Preferred stock, voting together as a class, elect to convert such preferred stock into shares of Common Stock.

(ii) “Conversion Price” means (A) the price per share of Common Stock paid by purchasers of shares of Common Stock in the applicable underwritten public offering (the “Offering Price”), multiplied by (B) the applicable Conversion Percentage (as defined below).

(iii) “Conversion Percentage” means (A) prior to the first anniversary of the issuance of the Notes (such issuance date of the Notes, the “Issuance Date”), 75%, and (B) on or after the first anniversary of the Issuance Date, 62.5%.

(d) Conversion Procedures; Other Notices. The Borrower shall give notice of a Qualified IPO, Non-Qualified IPO or Sale of the Borrower (as defined below) (each, a “Triggering Event”) to the Lender as soon as is reasonably practicable prior to the closing of such Triggering Event, but in any case at least (10) business days prior to the closing of any such Triggering Event.

3

(e) Cash in Lieu of Fractional Shares. No fractional share or interest of Common Stock or scrip representing fractional shares or interests shall be issued upon conversion of this Note. Instead of any fractional shares or interest of Common Stock, which would otherwise be issuable upon conversion of this Note, the Borrower shall pay to the Lender a cash adjustment in an amount equal to the product of such fractional interest multiplied by the Offering Price.

(f) Issuance of Common Stock. Upon the occurrence of any conversion specified in this Section 6, the Lender shall surrender this Note at the office of the Borrower or of its transfer agent against delivery of the applicable amount of Common Stock into which this Note surrendered was convertible on the date on which such conversion occurred. The Borrower shall not be obligated to issue Common Stock issuable upon such conversion unless the Note being converted is either delivered to the Borrower or any such transfer agent, or the Lender provides evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of the Note and the Lender agrees to indemnify and hold harmless the Borrower in respect of any such lost, stolen, destroyed or mutilated Note.

7. Sale of the Borrower.

(a) In the event of a Sale of the Borrower, but, for the avoidance of doubt, contingent upon the closing of such Sale of the Borrower, the Notes shall become due and payable on the closing date of such Sale of the Borrower in cash, in preference to all equity securities of the Borrower, for an amount equal to (i) the Outstanding Balance, divided by (ii) the applicable Conversion Percentage.

(b) “Sale of the Borrower” means (i) a merger or consolidation of the Borrower or any of its Subsidiaries with or into another corporation (with respect to which less than a majority of the outstanding voting power or equity securities of the surviving or consolidated corporation immediately following such event is held by persons or entities who were stockholders of the Borrower immediately prior to such event); (ii) the sale, license, disposition or other transfer of all or substantially all of the properties and assets of the Borrower or any of its Subsidiaries; (iii) any acquisition by any person (or group of affiliated or associated persons) of beneficial ownership of a majority of the equity of the Borrower or of any Subsidiary (whether or not newly-issued shares) in a single transaction or a series of related transactions; or (iv) any other similar change of control of fifty percent (50%) or more of the outstanding voting power of the Borrower or any Subsidiary.

8. Default. This Note shall be subject to the Event of Default provisions set forth in Article VII of the Purchase Agreement.

4

9. Governing Law. This Note shall be governed by and construed in accordance with the domestic laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflicting provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the laws of any jurisdiction other than the Commonwealth of Massachusetts to be applied. In furtherance of the foregoing, the internal law of the Commonwealth of Massachusetts will control the interpretation and construction of this Note, even if under such jurisdiction’s choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

10. Cancellation of Note. Upon the payment and/or conversion of the Outstanding Balance, or, if applicable, the Payoff Amount, this Note shall be canceled.

11. Collection Expenses. The Borrower further agrees, subject only to any limitation imposed by applicable law, to pay all expenses, including reasonable attorneys’ fees, incurred by the holder of this Note in endeavoring to collect any amounts payable hereunder which are not paid when due.

12. Amendment. Any provision of this Note, except for (i) the principal amount of this Note, (ii) the interest rate in connection therewith, (iii) Section 2, (iv) Section 3 and (v) Section 6, may be amended or waived with the written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding so long as such amendment or waiver does not materially adversely affect the rights and obligations of a Lender in a manner different from the other Lenders.

13. Waiver. Borrower hereby waives presentment, protest, demand for payment, notice of dishonor, and any and all other notices or demands in connection with the deliver, acceptance, performance, default, or enforcement of this Note.

14. Adjustment. All references to share amounts and prices herein shall be equitably adjusted to reflect any stock split, combination, stock dividend or similar event affecting the capital stock of the Borrower.

15. Notice. All notices shall be delivered pursuant to the terms of Section 9.5 of the Purchase Agreement.

16. Lender Actions. Lender may not take any action with respect to this Note, whether to enforce its rights under this Note or otherwise, without the prior written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding.

5

IN WITNESS WHEREOF, the undersigned has caused this instrument to be executed by its duly authorized officer as of the date first above written.

ASPEN AEROGELS, INC.
By:
Name:	John F. Fairbanks
Title:	Vice President and CFO

NOTE MODIFICATION AGREEMENT

This Note Modification Agreement (this “Agreement”) is entered into as of March 28, 2013 by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and the Purchaser set forth on the signature page hereto, being the Purchaser of one or more Notes issued pursuant to the terms and provisions of the Note Purchase Agreement, dated June 11, 2012, among the Company and the Purchasers party thereto, as amended by that certain Amendment No. 1 to Note Purchase Agreement dated September 26, 2012 and that certain Consent and Amendment No. 2 to Note Purchase Agreement dated of even date herewith (as amended, the “NPA”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the NPA.

WHEREAS, the Company and the undersigned Purchaser as a Lender under one or more Notes wish to amend and modify certain terms of such Note or Notes.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. The final paragraph of the legend of each Note is amended by deleting in its entirety and replacing it with the following:

THIS NOTE IS ALSO SUBJECT TO (A) A SUBORDINATION AGREEMENT BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO, DATED AS OF JUNE 11, 2012, JULY 17, 2012, OR SEPTEMBER 26, 2012, (B) A SUBORDINATION AGREEMENT BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO, DATED AS OF JUNE 11, 2012, JULY 17, 2012, OR SEPTEMBER 26, 2012 AND (C) THE SUBORDINATION AGREEMENT, DATED AS OF MARCH 28, 2013, BETWEEN THE SENIOR CREDITORS AND JUNIOR CREDITORS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

2. Section 2(a) of each Note is amended by deleting such section in its entirety and replacing it with the following:

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on December 6, 2016 (the “Maturity Date”).

3. Except to the extent amended hereby, all of the terms, provisions and conditions of each Note are hereby ratified and confirmed and shall remain in full force and effect.

4. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Agreement may be executed by facsimile or by electronic or PDF file.

[Signature pages follow]

[Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	CFO

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

GKFF VENTURES I, LLC
(f/k/a Argonaut Ventures I, LLC)
By:	/s/ Robert Thomas
Name:	Robert Thomas
Title:	Manager and Vice President

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

RESERVOIR CAPITAL MASTER FUND, L.P.
By:	Reservoir Capital Group, L.L.C.
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer
RESERVOIR CAPITAL MASTER FUND, L.P.
By:	RCP GP, LLC
Its:	General Partner
By:	/s/ Craig A. Huff
Name:	Craig A. Huff
Title:	Co-Chief Executive Officer

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

ARCAPITA VENTURES I LIMITED
By:	/s/ John Huntz
Name:	John Huntz
Title:	Executive Director

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

TENAYA CAPITAL IV, L.P.
By: Tenaya Capital IV Annex GP, LLC, its General Partner
By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact
TENAYA CAPITAL IV-C, L.P.
By: Tenaya Capital IV GP, LP, its General Partner
By: Tenaya Capital IV GP, LLC, its General Partner
By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact
TENAYA CAPITAL IV-P, L.P.
By: Tenaya Capital IV GP, LP, its General Partner
By: Tenaya Capital IV GP, LLC, its General Partner
By:	/s/ Dave Markland
Dave Markland
Attorney-In-Fact

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

BASF VENTURE CAPITAL GMBH
By:	/s/ Dirk Nachtigal
Name:	Dirk Nachtigal
Title:	Managing Director

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

LEHMAN BROTHERS OFFSHORE PARTNERSHIP ACCOUNT 2000/2001, L.P.
By:	Lehman Brothers Offshore Partners Ltd
Its:	General Partner
By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory
LEHMAN BROTHERS PARTNERSHIP ACCOUNT 2000/2001, L.P.
By:	LBI Group Inc.
Its:	General Partner
By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory
LEHMAN BROTHERS VENTURE CAPITAL PARTNERS II, L.P.
By:	Venture Associates II GP LP
Its:	General Partner
By:	Lehman Brothers Venture Associates II LLC
Its:	General Partner
By:	/s/ Ashvin Rao
Name:	Ashvin Rao
Title:	Authorized Signatory

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

ROCKPORT CAPITAL PARTNERS II, L.P.
By:	RockPort Capital II, L.L.C.
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner
RP CO-INVESTMENT FUND I, L.P.
By:	RP Co-Investments Fund I, GP, LLC
Its:	General Partner
By:	/s/ David J. Prend
Name:	David J. Prend
Title:	Managing General Partner

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

FIDELITY SELECT PORTFOLIOS: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
VARIABLE INSURANCE PRODUCTS FUND IV: INDUSTRIALS PORTFOLIO
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

FIDELITY ADVISOR SERIES VII: FIDELITY ADVISOR INDUSTRIALS FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY INDUSTRIALS CENTRAL FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY CENTRAL INVESTMENT PORTFOLIOS LLC: FIDELITY MATERIALS CENTRAL FUND
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer
FIDELITY PURITAN TRUST: FIDELITY PURITAN TRUST
By:	/s/ Stephen Sadoski
Name:	Stephen Sadoski
Title:	Deputy Treasurer

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

CONTRA COSTA CAPITAL, LLC
By:	/s/ James Huff
Name:	James Huff
Title:	Vice President

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

MOUNT HOPE ASPEN, LLC
By:	/s/ Brian Scanlan
Name:	Brian Scanlan
Title:	Manager

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Fred Smithson
Name:	Fred Smithson
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

NOTE MODIFICATION AGREEMENT

This Note Modification Agreement (this “Agreement”) is entered into as of May 6, 2013 by and among Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and the Purchaser set forth on the signature page hereto, being the Purchaser of one or more Notes issued pursuant to the terms and provisions of the Note Purchase Agreement, dated June 11, 2012, among the Company and the Purchasers party thereto, as amended by that certain Amendment No. 1 to Note Purchase Agreement dated September 26, 2012 and that certain Consent and Amendment No. 2 to Note Purchase Agreement dated March 28, 2013 (as amended, the “NPA”). Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the NPA.

WHEREAS, the Company and the undersigned Purchaser as a Lender under one or more Notes wish to amend and modify certain terms of such Note or Notes.

NOW, THEREFORE, for valid and adequate consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. The final paragraph of the legend of each Note is amended by deleting in its entirety and replacing it with the following:

THIS NOTE IS ALSO SUBJECT TO (A) A SUBORDINATION AGREEMENT BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO, DATED AS OF JUNE 11, 2012, JULY 17, 2012, OR SEPTEMBER 26, 2012, (B) A SUBORDINATION AGREEMENT BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO, DATED AS OF JUNE 11, 2012, JULY 17, 2012, OR SEPTEMBER 26, 2012 AND (C) THE SUBORDINATION AGREEMENT, DATED AS OF MAY 6, 2013, BETWEEN THE SENIOR CREDITORS AND JUNIOR CREDITORS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

2. Section 2(a) of each Note is amended by deleting such section in its entirety and replacing it with the following:

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on December 6, 2016 (the “Maturity Date”).

3. Except to the extent amended hereby, all of the terms, provisions and conditions of each Note are hereby ratified and confirmed and shall remain in full force and effect.

4. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original instrument and all which together shall constitute one and the same agreement. This Agreement may be executed by facsimile or by electronic or PDF file.

[Signature pages follow]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Vice President and CFO

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

NICHIAS CORPORATION
By:	/s/ Kunihiko Yano
Name:	Kunihiko Yano
Title:	President and Chief Executive Officer
	NICHIAS Corporation

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Thomas L. Cunningham Trust
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Susan Zimmerman
	Name:
	Title:	Trustee
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ William A. Sahlman
Name:	William A. Sahlman
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Charles C. Cunningham, Jr. Trust 1990
Name:	Charles C. Cunningham, Jr.
Title:	Trustee
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Melissa D. Spangler
Name:	Melissa D. Spangler
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Auchincloss & Ong Family Trust (d/d 5/5/98)
Name of Entity (Print or Type)
By:	/s/ Belita Ong
	Name of Entity (Print or Type): Belita Ong
	Its: Trustee
(Complete above if another entity signs for entity listed above)
By:	/s/ James Gordon Auchincloss
	Name:	James Gordon Auchincloss
	Title:	Trustee
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Jonathan F.P. Rose
Name:	Jonathan F.P. Rose
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ John Huntz
Name:	John Huntz
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ P. Ramsay Battin
Name:	P. Ramsay Battin
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Name of Entity (Print or Type)
By:	Jamie Trust
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Jamie McCourt, Trustee
	Name: Jamie McCourt
	Title: Trustee
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	Linnea J. Geiss
Name:
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Linnea J. Geiss
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Donald R. Young
Name:	Donald R. Young
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Edward Lamont
Name:	Edward Lamont
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Aerogel Korea
Name of Entity (Print or Type)
By:	Aerogel Korea
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Joo Young Park
	Name:	Joo Young Park
	Title:	CEO
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:

By:

Name:

Title:

ENTITY:

FORTE VENTURES L.P.
By:	Forte Capital Management L.L.C., its general partner
		By:	Hawkins Ventures, Inc., as Manager
			By:	/s/ Thomas N. Hawkins
				Thomas N. Hawkins, President & CEO

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Maricamp LLC
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ John A. Galat
	Name:	John A. Galat

	Title:	Owner
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:
Name:
Title:
ENTITY:
Protos, L.L.C.
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:	/s/ Thomas H. Grant
	Name:	Thomas H. Grant
	Title:	Manager
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

IN WITNESS WHEREOF, the parties hereto have executed this Note Modification Agreement as of the date first written above.

“Purchaser”

INDIVIDUAL:
By:	/s/ Fred Smithson
Name:	Fred Smithson
Title:
ENTITY:
Name of Entity (Print or Type)
By:
	Name of Entity (Print or Type):
	Its:
(Complete above if another entity signs for entity listed above)
By:
	Name:
	Title:
(Signature, name and title for individuals signing for entity)

[Signature Page to Note Modification Agreement – June 2012 NPA Notes]

EX-10.9

Exhibit 10.9

THIS PROMISSORY NOTE (THIS “NOTE”) AND THE SECURITIES ISSUABLE UPON CONVERSION HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS. THESE SECURITIES HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A VIEW TO DISTRIBUTION OR RESALE, AND MAY NOT BE MORTGAGED, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT FOR SUCH SECURITIES UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR, IF REASONABLY REQUESTED, AN OPINION OF COUNSEL SATISFACTORY TO ASPEN AEROGELS, INC. THAT REGISTRATION IS NOT REQUIRED UNDER SUCH ACT.

THIS NOTE IS ALSO SUBJECT TO FURTHER RESTRICTIONS ON TRANSFER AS PROVIDED IN SECTION 6.4 OF THAT CERTAIN NOTE AND WARRANT PURCHASE AGREEMENT, DATED AS OF MARCH 28, 2013, AMONG ASPEN AEROGELS, INC. AND THE PURCHASERS PARTY THERETO (AS MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

THIS NOTE HAS BEEN ISSUED WITH ORIGINAL ISSUE DISCOUNT (“OID”). BEGINNING ON [            ], THE HOLDER OF THIS NOTE MAY, UPON REQUEST, OBTAIN FROM THE CHIEF FINANCIAL OFFICER OF ASPEN AEROGELS, INC. THIS NOTE’S ISSUE PRICE, ISSUE DATE, AMOUNT OF OID AND YIELD TO MATURITY BY CONTACTING SUCH PERSON AT (508) 691-1111.

THIS NOTE IS ALSO SUBJECT TO (A) THE SUBORDINATION AGREEMENT, DATED AS OF [            ] BETWEEN SILICON VALLEY BANK AND THE PERSONS PARTY THERETO AND (B) THE SUBORDINATION AGREEMENT, DATED AS OF [            ], BETWEEN PJC CAPITAL LLC AND THE PERSONS PARTY THERETO (AS EACH AGREEMENT MAY BE AMENDED, RESTATED, SUPPLEMENTED OR OTHERWISE MODIFIED FROM TIME TO TIME).

ASPEN AEROGELS, INC.

SENIOR SUBORDINATED CONVERTIBLE NOTE

$[                    ] [            ], 2013            

FOR VALUE RECEIVED, ASPEN AEROGELS, INC., a Delaware corporation (the “Borrower”), hereby promises to pay to [    ] (the “Lender”), the principal sum of $[                    ] (the “Principal Amount”), together with interest thereon accruing on and from the date hereof until paid, at an annual rate equal to 8% (which shall be increased to 10% following the occurrence and during the continuance of any Event of Default in accordance with the terms of the Purchase Agreement), compounded annually on December 31 of each year. Interest shall be calculated based on a 360-day year, but in no event shall the rate of interest exceed the maximum rate, if any, allowable under applicable law. The Principal Amount plus accrued interest under this Note up to and including the applicable date is referred to herein as the “Outstanding Balance”.

This subordinated convertible promissory note (this “Note”) is issued by the Borrower pursuant to that certain Note and Warrant Purchase Agreement dated as of March 28, 2013 (the “Purchase Agreement”), entered into between the Borrower and the persons listed thereto (the “Purchasers”), and is subject to, and Borrower and Lender shall be bound by, all the terms, conditions and provisions of the Purchase Agreement. This Note and the other notes issued pursuant to the Purchase Agreement are hereinafter referred to as the “Notes.” The Lender and the other lenders with respect to the Notes are hereinafter referred to as the “Lenders.” Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to such terms in the Purchase Agreement.

1. Payment. Subject to Section 6 hereof, accrued interest shall be (i) payable in cash at the time Borrower pays the Principal Amount or such other amounts required to be paid under this Note pursuant to Sections 2, 3 or 7 hereof or (ii) converted together with the outstanding Principal Amount under this Note in accordance with Section 6 hereof. No interest shall be payable other than as set forth in the preceding sentence. Unless the indebtedness outstanding under this Note is converted in accordance with Section 6 hereof, all payments on account of principal and interest, or such other amounts required to be paid under this Note, shall be made in lawful money of the United States of America at the principal office of the Lender, or such other place as the holder hereof may from time to time designate in writing to the Borrower.

2. Payment at Maturity; Liquidation Event.

(a) Unless this Note is converted into capital stock of the Borrower in accordance with Section 6 hereof or repaid prior to the Maturity Date (as defined below) in accordance with, and subject to, Section 3 hereof, an amount equal to (i) the then Outstanding Balance, multiplied by (ii) 1.375 (the product of (i) and (ii), the “Payoff Amount”), shall be due and payable on March 28, 2016 (the “Maturity Date”).

(b) Unless this Note is otherwise repaid in accordance with Section 7, upon any voluntary or involuntary liquidation, dissolution or winding up of the affairs of the Borrower, and unless this Note has been previously converted as provided herein, an amount equal to the Outstanding Balance divided by the applicable Conversion Percentage (as defined below) shall be immediately due and payable to the Lender on the effective date of such liquidation, dissolution or winding up.

3. Prepayment. In the event of a prepayment of the Notes by the Borrower, the Notes shall become due and payable on the date of such prepayment in cash, in preference to all equity securities of the Borrower, for an amount equal to (i) the Outstanding Balance, divided by (ii) the applicable Conversion Percentage (as defined below).

4. Transfer and Exchange. The holder of this Note may, subject to any restrictions on transfers or assignments in Section 6.4 of the Purchase Agreement or the Stockholders’ Agreement (the “Transfer Restrictions”), surrender this Note at the principal office of the Borrower for transfer or exchange. Within a reasonable time after notice to the Borrower from such holder of its intention to make such exchange and without expense to such holder, except for any transfer or similar tax which may be imposed on the transfer or exchange, the Borrower shall issue in exchange therefor, in such denominations of at least $50,000 as shall be specified

by such holder, another note or notes for the same aggregate principal amount as the unpaid principal amount of the Note so surrendered, having the same maturity and rate of interest, containing the same provisions and subject to the same terms and conditions as the Note so surrendered. Subject to the Transfer Restrictions, each new Note shall be made payable to such person or persons, or transferees, as the holder of such surrendered Note may designate, and such transfer or exchange shall be made in such a manner that no gain or loss of principal or interest shall result therefrom.

5. New Note. Upon receipt of evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of this Note, and, in the case of any such loss, theft or destruction, upon delivery of a customary indemnity agreement to the Borrower, or, in the case of any such mutilation, upon surrender and cancellation of the Note, as the case may be, the Borrower will issue a new Note of like tenor, in lieu of such lost, stolen, destroyed or mutilated Note.

6. Conversion of Note.

(a) Qualified IPO. In the event of a Qualified IPO (as defined below), but contingent upon the closing of such Qualified IPO, the Outstanding Balance will automatically convert on the closing date of such Qualified IPO into an amount of unregistered shares of Common Stock, par value $0.001 per share, of the Borrower or such other equity securities offered in such public offering (as applicable, the “Common Stock”) equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price (as defined below).

(b) Non-Qualified IPO. In the event of an underwritten public offering of Common Stock other than a Qualified IPO (a “Non-Qualified IPO”), at the election of Lenders holding at least a majority of the then outstanding principal amount of the Notes, the Outstanding Balance will convert on the closing date of such Non-Qualified IPO into an amount of unregistered shares of Common Stock equal to (i) the Outstanding Balance on such closing date, divided by (ii) the applicable Conversion Price.

(c) Definitions.

(i) A “Qualified IPO” means the first underwritten public offering of Common Stock that results in the Common Stock being listed on a United States national securities exchange and (i) that has a minimum gross offering size of at least $60 million or (ii) in which the holders of a majority of the outstanding Notes elect to convert such Notes into shares of Common Stock.

(ii) “Conversion Price” means (A) the price per share of Common Stock paid by purchasers of shares of Common Stock in the applicable underwritten public offering (the “Offering Price”), multiplied by (B) the applicable Conversion Percentage (as defined below).

(iii) “Conversion Percentage” means (A) prior to the first anniversary of the issuance of the Notes (such issuance date of the Notes, the “Issuance Date”), 75%, and (B) on or after the first anniversary of the Issuance Date, 62.5%.

(d) Conversion Procedures; Other Notices. The Borrower shall give notice of a Qualified IPO, Non-Qualified IPO or Sale of the Borrower (as defined below) (each, a “Triggering Event”) to the Lender as soon as is reasonably practicable prior to the closing of such Triggering Event, but in any case at least (10) business days prior to the closing of any such Triggering Event.

(e) Cash in Lieu of Fractional Shares. No fractional share or interest of Common Stock or scrip representing fractional shares or interests shall be issued upon conversion of this Note. Instead of any fractional shares or interest of Common Stock, which would otherwise be issuable upon conversion of this Note, the Borrower shall pay to the Lender a cash adjustment in an amount equal to the product of such fractional interest multiplied by the Offering Price.

(f) Issuance of Common Stock. Upon the occurrence of any conversion specified in this Section 6, the Lender shall surrender this Note at the office of the Borrower or of its transfer agent against delivery of the applicable amount of Common Stock into which this Note surrendered was convertible on the date on which such conversion occurred. The Borrower shall not be obligated to issue Common Stock issuable upon such conversion unless the Note being converted is either delivered to the Borrower or any such transfer agent, or the Lender provides evidence reasonably satisfactory to the Borrower of the loss, theft, destruction or mutilation of the Note and the Lender agrees to indemnify and hold harmless the Borrower in respect of any such lost, stolen, destroyed or mutilated Note.

7. Sale of the Borrower.

(a) In the event of a Sale of the Borrower, but, for the avoidance of doubt, contingent upon the closing of such Sale of the Borrower, the Notes shall become due and payable on the closing date of such Sale of the Borrower in cash, in preference to all equity securities of the Borrower, for an amount (the “Borrower Sale Amount”) equal to (i) the Outstanding Balance, divided by (ii) the applicable Conversion Percentage; provided, however, that in the event such Sale of the Borrower is consummated on or prior to September 14, 2013 to any person who, prior to March 14, 2013, submitted a term sheet to the Borrower in connection with a potential acquisition of the Borrower, then the Borrower Sale Amount shall equal the Outstanding Balance.

(b) “Sale of the Borrower” means (i) a merger or consolidation of the Borrower or any of its Subsidiaries with or into another corporation (with respect to which less than a majority of the outstanding voting power or equity securities of the surviving or consolidated corporation immediately following such event is held by persons or entities who were stockholders of the Borrower immediately prior to such event); (ii) the sale, license, disposition or other transfer of all or substantially all of the properties and assets of the Borrower or any of its Subsidiaries; (iii) except as a result of the exercise of the Warrants by the Warrant holders or the conversion of either the Notes or the Prior Notes by the holders of such notes, (a) any acquisition by any person (or group of affiliated or associated persons) of beneficial ownership of a majority of the equity of the Borrower or of any Subsidiary (whether or not newly-issued shares) in a single transaction or a series of related transactions; or (b) any other similar change of control of fifty percent (50%) or more of the outstanding voting power of the Borrower or any Subsidiary.

8. Default. This Note shall be subject to the Event of Default provisions set forth in Article VII of the Purchase Agreement.

9. Governing Law. This Note shall be governed by and construed in accordance with the domestic laws of the State of New York, without giving effect to any choice of law or conflicting provision or rule (whether of the State of New York or any other jurisdiction) that would cause the laws of any jurisdiction other than the State of New York to be applied. In furtherance of the foregoing, the internal law of the State of New York will control the interpretation and construction of this Note, even if under such jurisdiction’s choice of law or conflict of law analysis, the substantive law of some other jurisdiction would ordinarily apply.

10. Cancellation of Note. Upon the payment and/or conversion of the Outstanding Balance, or, if applicable, the Payoff Amount, this Note shall be canceled.

11. Collection Expenses. The Borrower further agrees, subject only to any limitation imposed by applicable law, to pay all expenses, including reasonable attorneys’ fees, incurred by the holder of this Note in endeavoring to collect any amounts payable hereunder which are not paid when due.

12. Amendment. Any provision of this Note, except for (i) the principal amount of this Note, (ii) the interest rate in connection therewith, (iii) Section 2, (iv) Section 3 and (v) Section 6, may be amended or waived with the written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding so long as such amendment or waiver does not materially adversely affect the rights and obligations of a Lender in a manner different from the other Lenders.

13. Waiver. Borrower hereby waives presentment, protest, demand for payment, notice of dishonor, and any and all other notices or demands in connection with the deliver, acceptance, performance, default, or enforcement of this Note.

14. Adjustment. All references to share amounts and prices herein shall be equitably adjusted to reflect any stock split, combination, stock dividend or similar event affecting the capital stock of the Borrower.

15. Notice. All notices shall be delivered pursuant to the terms of Section 9.5 of the Purchase Agreement.

16. Lender Actions. Lender may not take any action with respect to this Note, whether to enforce its rights under this Note or otherwise, without the prior written consent of Lenders holding at least 66 2/3% of the aggregate principal amount of the Notes then outstanding.

IN WITNESS WHEREOF, the undersigned has caused this instrument to be executed by its duly authorized officer as of the date first above written.

ASPEN AEROGELS, INC.
By:
Name:	John F. Fairbanks
Title:	Vice President and CFO

[Signature Page to Senior Subordinated Convertible Note]

EX-10.10

Exhibit 10.10

EXECUTIVE AGREEMENT

This Amended and Restated Executive Agreement (this “Agreement”) is dated as of August 5, 2011, by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and Donald R. Young (the “Executive”).

Recitals:

A. The Company and the Executive previously entered into an employment agreement dated as of March 17, 2010.

B. The Company and the Executive desire to amend and restate that agreement in the form of this Agreement to provide for the terms and conditions of the Executive’s employment with the Company.

Agreement:

NOW, THEREFORE, the parties hereto agree as follows:

1. Definitions. As used herein, the following terms shall have the following meanings.

“Board” means the Company’s board of directors.

“Cause” means: (i) willful misconduct, dishonesty, fraud or breach of fiduciary duty to the Company; (ii) deliberate disregard of the lawful rules or policies of the Company, or breach of an employment or other agreement with the Company, which results in direct or indirect loss, damage or injury to the Company; (iii) the unauthorized disclosure of any trade secret or confidential information of the Company; or (iv) the commission of an act which constitutes unfair competition with the Company or which induces any customer or supplier to breach a contract with the Company. For purposes hereof, whether or not the Executive has committed an act or omission of the type referred to in subparagraphs (i) through (iv) above will be determined by the Board in its reasonable, good faith discretion, based upon the facts known to the Board at the relevant time. Any termination by the Company of the Executive’s employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Cause for purposes of this Agreement.

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which was a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized by the Company for its general corporate purposes or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person.

“Employment, Confidentiality and Non-Competition Agreement” means that certain Employment, Confidentiality and Non-Competition Agreement dated November 12, 2001 by and between the Executive and the Company.

“Good Reason” means: (i) any material breach by the Company of this Agreement that is not cured by the Company within thirty (30) days after written notice specifying in reasonable detail the nature of such material breach is provided to the Company by the Executive; (ii) the demotion of the Executive such that the Executive no longer serves as the CEO of the Company or a material reduction in the Executive’s current duties and authority as the CEO of the Company, in each case, without his consent; (iii) the written demand by the Company for the Executive to relocate or commute more than 40 miles from Brookline, Massachusetts without his consent; or (iv) any reduction by the Company in the Executive’s Base Salary without his consent. For purposes hereof, whether or not the Executive has Good Reason to terminate his employment by the Company pursuant to subparagraphs (i) through (iv) above will be determined by the Board in its reasonable, good faith discretion, based upon the facts known to the Board at the relevant time. Any termination by the Executive of his employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Good Reason for purposes of this Agreement.

“Permanent Disability” means the Executive is unable to perform, by reason of physical or mental incapacity, his then duties or obligations to the Company, for a total period of one hundred eighty (180) days in any three hundred sixty (360) day period.

“Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

2. Employment. The Company agrees to employ the Executive, and the Executive hereby accepts employment with the Company consistent with the Executive’s position and duties, upon the terms and conditions set forth in this Agreement for the period beginning on the date hereof and ending as provided in Section 2(c) (the “Employment Period”).

(a) Position and Duties.

(i) During the Employment Period, the Executive shall serve as Chief Executive Officer of the Company and shall have the duties, responsibilities and authority consistent with such position that are designated by the Board, subject to the direction and supervision of the Board. With the help and under the guidance of the Board, the Executive will direct the formulation, refinement and implementation of the strategic plan for the growth and operation of the Company and recruit the necessary senior management team to execute the plan. The Executive’s goal is to create shareholder value by establishing the Company as the leading global supplier of Aerogel products.

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(ii) The Executive shall devote his best efforts and his full business time and attention (except for permitted vacation periods and reasonable periods of illness or other incapacity) to the business and affairs of the Company. The Executive shall perform his duties and responsibilities to the best of his abilities in a diligent, trustworthy, businesslike and efficient manner. Notwithstanding the foregoing, the Executive may, to the extent not otherwise prohibited by this Agreement, devote such amount of time as does not interfere or compete with the performance of the Executive’s duties under this Agreement to any one or more of the following activities: (i) engaging in charitable activities, including serving on the boards of directors of charitable organizations or (ii) serving on the board of directors of any other company with the prior written approval of the Board.

(iii) In addition, so long as the Executive is employed by the Company as its Chief Executive Officer, the Executive shall be entitled to serve as a director of the Company.

(b) Salary and Benefits.

(i) During the Employment Period, the Executive’s base salary shall be $329,400 per year (such annual salary, as it may be adjusted upward by the Board or a committee thereof in its discretion, being referred to as the “Base Salary”). The Base Salary shall be payable in regular installments in accordance with the Company’s general payroll practices, shall be subject to customary withholding and may be increased (but not decreased) at the discretion of the Board or a committee thereof.

(ii) In addition to the Base Salary, Executive shall be eligible to receive an annual cash incentive bonus payment (each, a “Performance Bonus”) in an amount, if any, to be determined by the Company’s Board or a committee thereof.

(iii) The Company will reimburse the Executive for all reasonable travel and other expenses incurred by the Executive in connection with the performance of his duties and obligations under this Agreement. The Executive shall comply with such reasonable limitations and reporting requirements with respect to expenses as may be established by the Company from time to time.

(iv) In addition, the Executive will be entitled to participate in all compensation or employee benefit plans or programs and receive all benefits and perquisites for which salaried employees of the Company generally are eligible under any plan or program now or established later by the Company on the same basis as similarly situated senior executives of the Company. The Executive will participate to the extent permissible under the terms and provisions of such plans or programs, in accordance with program provisions. Nothing in this Agreement will preclude the Company from amending or terminating any of the plans or programs applicable to salaried employees or senior executives of the Company as long as such amendment or termination is applicable to all salaried employees or senior executives, as the case may be, so long as such plans or programs are replaced with plans no less favorable, in the aggregate, than existing plans.

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(c) Employment at Will. The Executive and the Company understand and agree that the Executive is an employee at will, and that the Executive may resign, or the Company may terminate the Executive’s employment, at any time and for any or for no reason. Nothing in this Agreement shall be construed to alter the at-will nature of the Executive’s employment, nor shall anything in this Agreement be construed as providing the Executive with a definite term of employment.

(d) Severance. If the Executive’s employment with the Company is terminated (i) by the Company without Cause; or (ii) by the Executive for Good Reason within thirty (30) days after the occurrence of an event constituting Good Reason (including the expiration of any applicable cure periods), the Executive shall be entitled to receive an amount equal to the Executive’s Base Salary (prior to any reduction) for six (6) months following the date of such termination, be entitled to continued participation on substantially similar terms in all employee benefit plans and programs to which he was entitled to participate in as of the date of such termination for six (6) months following the date of such termination, and shall be entitled to receive any accrued but unpaid bonuses or commissions then owed or fully earned by the Executive in accordance with Section 2(b)(ii) above (collectively, the “Severance Amount”). All amounts payable to the Executive pursuant to this provision shall be payable in regular installments in accordance with the Company’s regular payroll practices and subject to customary withholding. The Executive hereby agrees that no severance compensation shall be payable upon termination of the Executive’s employment with the Company (i) by the Company with Cause; (ii) by the Executive without Good Reason; or (iii) as a result of the Executive’s death or Permanent Disability, and the Executive hereby waives any claim for severance compensation except as set forth in this Section 2(d).

(e) Termination or Reduction of Severance. If at any time after termination of employment hereunder the Executive breaches any of the provisions set forth in the Employment, Confidentiality and Non-Competition Agreement, and if the Executive fails to cure each such breach, in all material respects, within thirty (30) days after the Company has given to the Executive written notice of such breach, the Company shall no longer be obligated to make any payments of the Severance Amount pursuant to Section 2(d) above.

(f) Change of Control. In addition to the provisions of Section 2(d), if a “Change of Control” occurs and the Executive does not receive an offer to remain employed by the Company as its chief executive officer (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms (including severance and termination provisions) as contained herein for at least two years, and the Executive is terminated without Cause or resigns for any reason within the two year period following the Change of Control event, the Executive shall be entitled upon his termination of employment to receive the Severance Amount payable in accordance with the provisions of Section 2(d).

(g) Options. Reference is hereby made to that certain Incentive Stock Option Agreement dated November 11, 2009 by and between the Company and the Executive (the “Option Agreement”) pursuant to which the Executive was granted an option to purchase certain shares of the Company’s common stock (the “Option Shares”). This paragraph shall be deemed by each of the Company and the Executive to be a corrective amendment to the Option Agreement to reflect the approved terms as of the date of grant and shall supplement and

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supercede any contrary terms therein. In addition, in the event that the Executive should after March 17, 2010 receive any additional grants of stock options or restricted stock awards, this paragraph shall be deemed by each of the Company and the Executive to be an amendment to the agreement or agreements pursuant to which any such stock options or restricted stock awards may be granted and shall supplement and supercede any contrary terms therein (and any reference to “Option Agreement” or “Option Shares” below shall be deemed to include any such later granted stock options or restricted stock awards). Upon the (i) consummation of a Change of Control transaction, unless the Executive receives an offer to remain employed by the Company as its chief executive officer (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms as contained herein for at least two years following the Change of Control event; or (ii) termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time during the two (2) year period following the consummation of a Change of Control transaction, any and all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. In addition, if upon a merger, consolidation or sale of all or substantially all of the Company’s assets (a “Corporate Transaction”) the Option Shares do not continue in the form of equity in the successor or acquiring entity such that vesting may continue to accrue after the Corporate Transaction then immediately prior to such Corporate Transaction all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. Upon a termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time after March 17, 2011, a number of unvested Option Shares as would have vested in the three (3) months following such termination of employment (and assuming for this purpose only) had Executive continued to be employed by the Company, shall thereupon immediately vest and become immediately exercisable. Notwithstanding anything to the contrary contained in any Option Agreement, Executive’s option to purchase vested Option Shares shall be exercisable for the entire ten (10) year term of the option in accordance with Section 4 of the Option Agreement. For the avoidance of doubt, the 90 day post-termination of employment exercise period shall not be applicable to the exercise of the Option Shares as provided above.

(h) Parachute Payments. If Independent Tax Counsel (as that term is defined below) determines that the aggregate payments and benefits provided or to be provided to the Executive pursuant to this Agreement, and any other payments and benefits provided or to be provided to the Executive from the Company or any of its subsidiaries or other affiliates or any successors thereto constitute “parachute payments” as defined in Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”) (or any successor provision thereto) (“Parachute Payments”) that would be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then, except as otherwise provided in the next sentence, such Parachute Payments shall be reduced to the extent the Independent Tax Counsel shall determine is necessary (but not below zero) so that no portion thereof shall be subject to the Excise Tax. If Independent Tax Counsel determines that the Executive would receive in the aggregate greater payments and benefits on an after tax basis if the Parachute Payments were not reduced pursuant to this Section 2(h), then no such reduction shall be made. The determination of which payments or benefits shall be reduced to avoid the Excise Tax shall be made by the Independent Tax Counsel, provided that the Independent Tax Counsel shall reduce or eliminate, as the case may be, payments or benefits in the order that it determines will produce the required deduction in total Parachute Payments with the least reduction in economic value to the Executive of such

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payments. The determination of the Independent Tax Counsel under this Section 2(h) shall be final and binding on all parties hereto. For purposes of this Section 2(h), “Independent Tax Counsel” shall mean a lawyer, a certified public accountant with a nationally recognized accounting firm, or a compensation consultant with a nationally recognized actuarial and benefits consulting firm with expertise in the area of executive compensation tax law, who shall be selected by the Board, and whose fees and disbursements shall be paid by the Company.

(i) Severance and Release. The Executive’s right to receive payment of the Severance Amount shall be contingent upon the Executive’s execution and non-revocation (other than in the case of Executive’s death) within forty-five (45) days of his date of termination of a general release reasonably satisfactory to the Company releasing the Company, its officers, agents, stockholders, and affiliates from any liability for any matter other than for payments under this Agreement and contractual obligations under other written agreements which form shall be provided to the Executive on or prior to his date of termination (the “Release”). The Company hereby agrees that upon the lapse of the period for revocation, if the Executive has not exercised his revocation right, the Company will execute a counterpart of the Release and deliver it to Executive forthwith. The payment of the Severance Amount shall commence within the sixty (60) day period following the Executive’s date of termination; provided that if a new calendar year commences during this period, the payments shall commence no earlier than January 2 of such new calendar year. The first payment after execution of the Release shall include all amounts that would have been paid following the date of termination had the Release been effective immediately following the date of termination but which were not yet paid.

3. Representations and Warranties of the Executive. Executive hereby represents and warrants to the Company that:

(a) The Executive:

(i) has not been convicted within the last five (5) years of any felony or misdemeanor in connection with the offer, purchase, or sale of any security or any felony involving fraud or deceit, including, but not limited to, forgery, embezzlement, obtaining money under false pretenses, larceny, or conspiracy to defraud;

(ii) is not currently subject to any state administrative enforcement order or judgment entered by a state securities administrator within the last five (5) years and is not subject to any state’s administrative enforcement order or judgment in which fraud or deceit (including, but not limited to, making untrue statements of material facts and omitting to state material facts) was found in which the order or judgment was entered within the last five (5) years; and

(iii) is a citizen of the United States of America and resident of the Commonwealth of Massachusetts.

(b) This Agreement constitutes the legal, valid and binding obligations of the Executive, enforceable in accordance with its terms, and the execution, delivery and performance of this Agreement by the Executive does not and will not conflict with, violate or cause a breach of any agreement, contract or instrument to which the Executive is a party or any judgment, order or decree to which the Executive is subject.

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4. Representations and Warranties of the Company. The Company hereby represents and warrants to the Executive that:

(a) The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite corporate power and authority to carry out the transactions contemplated by this Agreement.

(b) The execution, delivery and performance of this Agreement has been duly authorized by the Company. This Agreement constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Agreement, and the fulfillment of and compliance with the respective terms hereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice to any court or administrative or governmental body pursuant to, the charter or bylaws of the Company, or any law, statute, rule or regulation to which the Company is subject, or any agreement, instrument, order, judgment or decree to which the Company is subject.

5. Confidentiality, Non-Competition and Non-Solicitation. The Executive hereby reaffirms, confirms and approves the Employment, Confidentiality and Non-Competition Agreement as a binding obligation of the Executive, enforceable in accordance with its terms. The Executive acknowledges and agrees that any Base Salary and/or Performance Bonus paid to the Executive pursuant to this Agreement shall serve as additional consideration for the Executive’s obligations under the Employment, Confidentiality and Non-Competition Agreement.

6. Notices. All notices, demands or other communications to be given or delivered under or by reason of the provisions of this Agreement will be in writing and will be deemed to have been given when delivered personally, mailed by certified or registered mail, return receipt requested and postage prepaid, or sent via a nationally recognized overnight courier, or sent via facsimile to the recipient with a confirmation of receipt and accompanied by a certified or registered mailing. Such notices, demands and other communications will be sent to the address indicated below:

To the Company:

Aspen Aerogels, Inc.

30 Forbes Road

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: Board of Directors

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with copies (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 239-0100

Facsimile: (617) 227-4420

Attention: Christopher W. Nelson

To the Executive:

7 Dana Street

Brookline, MA 02445

Telephone: (617) 734-3056

Facsimile: (617) 730-8181

or to such other address or to the attention of such other person as the recipient party has specified by prior written notice to the sending party.

7. Miscellaneous.

(a) Severability. Whenever possible, each provision of this Agreement will be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any jurisdiction, such invalidity, illegality or unenforceability will not affect any other provision or any other jurisdiction, but this Agreement will be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or unenforceable provision had never been contained herein.

(b) Complete Agreement. This Agreement and the agreements referred to herein (including, without limitation, the Employment, Confidentiality and Non-Competition Agreement) embody the complete agreement and understanding among the parties and supersede and preempt any prior understandings, agreements or representations by or among the parties, written or oral, which may have related to the subject matter hereof. This Agreement supercedes and terminates that certain Executive Agreement dated as of November 16, 2001 by and between the Executive and the Company.

(c) Waiver of Jury Trial. The parties to this Agreement each hereby waives, to the fullest extent permitted by law, any right to trial by jury of any claim, demand, action, or cause of action (i) arising under this Agreement or (ii) in any way connected with or related or incidental to the dealings of the parties hereto in respect of this Agreement or any of the transactions related hereto, in each case whether now existing or hereafter arising, and whether in contract, tort, equity, or otherwise. The parties to this Agreement each hereby agrees and consents that any such claim, demand, action, or cause of action shall be decided by court trial without a jury and that the parties to this Agreement may file an original counterpart or a copy of this Agreement with any court as written evidence of the consent of the parties hereto to the waiver of their right to trial by jury.

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(d) Counterparts; Facsimile Transmission. This Agreement may be executed simultaneously in two or more counterparts, any one of which need not contain the signatures of more than one party, but all such counterparts taken together will constitute one and the same Agreement. This Agreement may also be executed and delivered by facsimile transmission.

(e) Successors and Assigns. The provisions hereof shall inure to the benefit of, and be binding upon and assignable to, successors of the Company by way of merger, consolidation or sale. The Executive may not assign or delegate to any third person the Executive’s obligations under this Agreement. The rights and benefits of the Executive under this Agreement are personal to him and no such right or benefit shall be subject to voluntary or involuntary alienation, assignment or transfer. The Company shall require any successor (whether direct or indirect, by purchase, merger, consolidation or otherwise) to all or substantially all of the business and/or assets of the Company expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would have been required to perform it if no such succession had taken place. As used in this Agreement, “the Company” shall mean both the Company as defined above and any such successor that assumes and agrees to perform this Agreement, by operation of law or otherwise.

(f) Governing Law. All issues concerning this Agreement shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflict of law provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the application of the law of any jurisdiction other than the Commonwealth of Massachusetts.

(g) Remedies. The parties hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and that any party may in its sole discretion apply to any court of law or equity of competent jurisdiction (without posting any bond or deposit) for specific performance and/or injunctive or other relief in order to enforce or prevent any violations of the provisions of this Agreement.

(h) Amendment and Waiver. The provisions of this Agreement may be amended and waived only with the prior written consent of the Company and the Executive.

(i) Certain Expenses. The Company agrees to pay, as incurred, to the fullest extent permitted by law, or indemnify the Executive if such payment is not legally permitted, for all legal fees and expenses that the Executive may in good faith incur as a result of any contest by the Company, the Executive or others of the validity or enforceability of or liability under, or otherwise involving, any provision of this Agreement; provided, however, that the Executive shall reimburse the Company for all such payments made by the Company in connection with a contest by the Company if a court of competent jurisdiction or an arbitrator shall find that the Executive did not act in good faith in connection with such contest.

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(j) Compliance with Code Section 409A. To the extent that any payment under this Agreement constitutes “nonqualified deferred compensation” for purposes of Section 409A of the Internal Revenue Code of 1986, as amended (the “Code”), (i) a termination of employment shall not be deemed to have occurred for purposes of any provision of this Agreement providing for the payment of any amounts or benefits upon or following a termination of employment unless such termination is also a “separation from service” within the meaning of Code Section 409A and, for purposes of any such provision of this Agreement, references to a “termination ,” “termination of employment” or like terms shall mean “separation from service,” (ii) the Executive’s right to receive any installment payments pursuant to this Agreement shall be treated as a right to receive a series of separate and distinct payments, and (iii) if the Executive is deemed on the date of termination to be a “specified employee” within the meaning of that term under Code Section 409A(a)(2)(B), then with regard to any payment or the provision of any benefit that is considered deferred compensation under Code Section 409A payable on account of a “separation from service,” such payment or benefit shall be made or provided at the date which is the earlier of (A) the expiration of the six (6)-month period measured from the date of such “separation from service” of Executive, and (B) the date of Executive’s death, to the extent required under Code Section 409A. Upon the expiration of the foregoing delay period, all payments and benefits delayed pursuant to this Section 7(j) (whether they would have otherwise been payable in a single sum or in installments in the absence of such delay) shall be paid in a lump sum, and any remaining payments and benefits due under this Agreement shall be paid or provided in accordance with the normal payment dates specified for them herein.

(k) Survival. The provisions of Sections 1, 2 and 5 through 7 of this Agreement shall survive any termination of this Agreement in accordance with the terms of such sections.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first above written.

THE COMPANY: ASPEN AEROGELS, INC.
By:	/s/ John Fairbanks
	Name: John Fairbanks
	Title:   Chief Financial Officer
THE EXECUTIVE:
By:	/s/ Donald R. Young
	Donald R. Young

[Signature Page to Young Executive Agreement]

EXHIBIT A:

EMPLOYMENT, CONFIDENTIALITY

AND NON-COMPETITION AGREEMENT

Execution Copy

FIRST AMENDMENT

TO

EXECUTIVE AGREEMENT

This First Amendment to the Amended and Restated Executive Agreement dated August 5, 2011 (the “Agreement”), by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and Donald R. Young (the “Executive”) is made effective as of October 23, 2012.

RECITALS

WHEREAS, the parties desire to amend the Agreement to revise the Base Salary, Performance Bonus, and severance of the Executive and to make other clarifying changes, and

WHEREAS, the Board of Directors of the Company has approved the terms of this Amendment;

NOW THEREFORE, the Company and the Executive do hereby amend this Agreement as follows:

W I T N E S S E T H

1. Section 1 Definition of “Change of Control” is hereby amended in its entirety by deleting and replacing the current language with the following:

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which is a shareholder of the Company on March 17,2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized for its general corporate

1

purposes (including without limitation the retirement or repayment of outstanding debt obligations), or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person.

2. Section 2(b)(i) is hereby amended in its entirety by deleting and replacing the current language with the following:

“During the Employment Period, effective as of October 1, 2012, the Executive’s base salary shall be $450,000 per year (such annual salary, as it may be adjusted upward by the Board in its discretion, being referred to as the “Base Salary”). The Base Salary shall be payable in regular installments in accordance with the Company’s general payroll practices, shall be subject to customary withholding and may be increased (but not decreased) at the discretion of the Board.”

3. Section 2(b)(ii) is hereby amended in its entirety by deleting and replacing the current language with the following:

“In addition to the Base Salary, Executive shall be eligible to receive an annual cash incentive bonus payment (each, a “Performance Bonus”) in an amount, if any, to be determined by the Company’s Board. The annual target Performance Bonus for Executive for the 2013 plan year and beyond will be 75% of Executive’s Base Salary. Further, during the Employment Period, Executive shall be eligible for a one-time bonus of $300,000 if the Company consummates an initial public offering of its common stock prior to December 31, 2012.”

4. Section 2(d) is hereby amended by replacing the phrase “six (6) months” with the phrase “twelve (12) months” each time it appears in such section.

5. This First Amendment shall be made part of the Agreement and all other terms and conditions as set forth in the Agreement shall remain unchanged, except as modified pursuant to the terms of this First Amendment.

[Signature Page Follows]

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IN WITNESS WHEREOF, the parties have executed this First Amendment as of the day and year first above written.

THE COMPANY:
ASPEN AEROGELS, INC.
By:	/s/ John Fairbanks
Name:	John Fairbanks
Title:	Chief Financial Officer
THE EXECUTIVE:
/s/ Donald R. Young
Donald R. Young

[Signature Page to First Amendment to Executive Agreement – Donald R. Young]

EX-10.11

Exhibit 10.11

EXECUTIVE AGREEMENT

This Amended and Restated Executive Agreement (this “Agreement”) is dated as of August 5, 2011, by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and John Fairbanks (the “Executive”).

Recitals:

A. The Company and the Executive previously entered into an employment agreement dated as of March 17, 2010.

B. The Company and the Executive desire to amend and restate that agreement in the form of this Agreement to provide for the terms and conditions of the Executive’s employment with the Company.

Agreement:

NOW, THEREFORE, the parties hereto agree as follows:

1. Definitions. As used herein, the following terms shall have the following meanings.

“Board” means the Company’s board of directors.

“Cause” means: (i) willful misconduct, dishonesty, fraud or breach of fiduciary duty to the Company; (ii) deliberate disregard of the lawful rules or policies of the Company, or breach of an employment or other agreement with the Company, which results in direct or indirect loss, damage or injury to the Company; (iii) the unauthorized disclosure of any trade secret or confidential information of the Company; or (iv) the commission of an act which constitutes unfair competition with the Company or which induces any customer or supplier to breach a contract with the Company. For purposes hereof, whether or not the Executive has committed an act or omission of the type referred to in subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Company of the Executive’s employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Cause for purposes of this Agreement.

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which was a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized by the Company for its general corporate purposes or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person.

“Good Reason” means: (i) any material breach by the Company of this Agreement that is not cured by the Company within thirty (30) days after written notice specifying in reasonable detail the nature of such material breach is provided to the Company by the Executive; (ii) the demotion of the Executive such that the Executive no longer serves in the position specified in Section 2(a)(i) below or a material reduction in the Executive’s current duties and authority in the position specified in Section 2(a)(i) below, in each case, without his consent; (iii) the written demand by the Company for the Executive to relocate or commute more than 40 miles from Northborough, Massachusetts without his consent; or (iv) any reduction by the Company in the Executive’s Base Salary without his consent. For purposes hereof, whether or not the Executive has Good Reason to terminate his employment by the Company pursuant to subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Executive of his employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Good Reason for purposes of this Agreement.

“Permanent Disability” means the Executive is unable to perform, by reason of physical or mental incapacity, his then duties or obligations to the Company, for a total period of one hundred eighty (180) days in any three hundred sixty (360) day period.

“Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

“Related Agreement” means any confidentiality, non-competition, intellectual property assignment or similar agreement by and between the Executive and the Company, whether entered into on or prior to the date of the Agreement or entered into subsequent to the date of the Agreement.

3. Employment. The Company agrees to employ the Executive, and the Executive hereby accepts employment with the Company consistent with the Executive’s position and duties, upon the terms and conditions set forth in this Agreement for the period beginning on the date hereof and ending as provided in Section 2(c) (the “Employment Period”).

(a) Position and Duties.

(i) During the Employment Period, the Executive shall serve as Chief Financial Officer of the Company and shall have the duties, responsibilities and authority consistent with such position that are designated by the President, subject to the direction and supervision of the President.

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(ii) The Executive shall devote his best efforts and his full business time and attention (except for permitted vacation periods and reasonable periods of illness or other incapacity) to the business and affairs of the Company. The Executive shall perform his duties and responsibilities to the best of his abilities in a diligent, trustworthy, businesslike and efficient manner. Notwithstanding the foregoing, the Executive may, to the extent not otherwise prohibited by this Agreement, devote such amount of time as does not interfere or compete with the performance of the Executive’s duties under this Agreement to any one or more of the following activities: (i) engaging in charitable activities, including serving on the boards of directors of charitable organizations or (ii) serving on the board of directors of any other company with the prior written approval of the Company.

(b) Salary and Benefits.

(i) During the Employment Period, the Executive’s base salary shall be $244,300 per year (such annual salary, as it may be adjusted upward by the Board or a committee thereof in its discretion, being referred to as the “Base Salary”). The Base Salary shall be payable in regular installments in accordance with the Company’s general payroll practices, shall be subject to customary withholding and may be increased (but not decreased) at the discretion of the Board or a committee thereof.

(ii) In addition to the Base Salary, Executive shall be eligible to receive an annual cash incentive bonus payment (each, a “Performance Bonus”) in an amount, if any, to be determined by the Company’s Board or a committee thereof.

(iii) The Company will reimburse the Executive for all reasonable travel and other expenses incurred by the Executive in connection with the performance of his duties and obligations under this Agreement. The Executive shall comply with such reasonable limitations and reporting requirements with respect to expenses as may be established by the Company from time to time.

(iv) In addition, the Executive will be entitled to participate in all compensation or employee benefit plans or programs and receive all benefits and perquisites for which salaried employees of the Company generally are eligible under any plan or program now or established later by the Company on the same basis as similarly situated senior executives of the Company. The Executive will participate to the extent permissible under the terms and provisions of such plans or programs, in accordance with program provisions. Nothing in this Agreement will preclude the Company from amending or terminating any of the plans or programs applicable to salaried employees or senior executives of the Company as long as such amendment or termination is applicable to all salaried employees or senior executives, as the case may be, so long as such plans or programs are replaced with plans no less favorable, in the aggregate, than existing plans.

(c) Employment at Will. The Executive and the Company understand and agree that the Executive is an employee at will, and that the Executive may resign, or the Company may terminate the Executive’s employment, at any time and for any or for no reason. Nothing in this Agreement shall be construed to alter the at-will nature of the Executive’s employment, nor shall anything in this Agreement be construed as providing the Executive with a definite term of employment.

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(d) Severance. If the Executive’s employment with the Company is terminated (i) by the Company without Cause; or (ii) by the Executive for Good Reason within thirty (30) days after the occurrence of an event constituting Good Reason (including the expiration of any applicable cure periods), the Executive shall be entitled to receive an amount equal to the Executive’s Base Salary (prior to any reduction) for three (3) months following the date of such termination, be entitled to continued participation on substantially similar terms in all employee benefit plans and programs to which he was entitled to participate in as of the date of such termination for three (3) months following the date of such termination, and shall be entitled to receive any accrued but unpaid bonuses or commissions then owed or fully earned by the Executive in accordance with Section 2(b)(ii) above (collectively, the “Severance Amount”). All amounts payable to the Executive pursuant to this provision shall be payable in regular installments in accordance with the Company’s regular payroll practices and subject to customary withholding. The Executive hereby agrees that no severance compensation shall be payable upon termination of the Executive’s employment with the Company (i) by the Company with Cause; (ii) by the Executive without Good Reason; or (iii) as a result of the Executive’s death or Permanent Disability, and the Executive hereby waives any claim for severance compensation except as set forth in this Section 2(d).

(e) Termination or Reduction of Severance. If at any time after termination of employment hereunder the Executive breaches any of the provisions set forth in any Related Agreement, and if the Executive fails to cure each such breach, in all material respects, within thirty (30) days after the Company has given to the Executive written notice of such breach, the Company shall no longer be obligated to make any payments of the Severance Amount pursuant to Section 2(d) above.

(f) Change of Control. In addition to the provisions of Section 2(d), if a “Change of Control” occurs and the Executive does not receive an offer to remain employed by the Company in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms (including severance and termination provisions) as contained herein for at least two years, and the Executive is terminated without Cause or resigns for any reason within the two year period following the Change of Control event, the Executive shall be entitled upon his termination of employment to receive the Severance Amount payable in accordance with the provisions of Section 2(d).

(g) Options. Reference is hereby made to that certain Incentive Stock Option Agreement dated November 11, 2009 by and between the Company and the Executive (the “Option Agreement”) pursuant to which the Executive was granted an option to purchase certain shares of the Company’s common stock (the “Option Shares”). This paragraph shall be deemed by each of the Company and the Executive to be a corrective amendment to the Option Agreement to reflect the approved terms as of the date of grant and shall supplement and supercede any contrary terms therein. In addition, in the event that the Executive should after March 17, 2010 receive any additional grants of stock options or restricted stock awards, this paragraph shall be deemed by each of the Company and the Executive to be an amendment to the agreement or agreements pursuant to which any such stock options or restricted stock awards may be granted and shall supplement and supercede any contrary terms therein (and any reference to “Option Agreement” or “Option Shares” below shall be deemed to include any such later granted stock options or restricted stock awards). Upon the (i) consummation of a Change

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of Control transaction, unless the Executive receives an offer to remain employed by the Company in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms as contained herein for at least two years following the Change of Control event; or (ii) termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time during the two (2) year period following the consummation of a Change of Control transaction, any and all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. In addition, if upon a merger, consolidation or sale of all or substantially all of the Company’s assets (a “Corporate Transaction”) the Option Shares do not continue in the form of equity in the successor or acquiring entity such that vesting may continue to accrue after the Corporate Transaction then immediately prior to such Corporate Transaction all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. Upon a termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time after March 17, 2011, a number of unvested Option Shares as would have vested in the three (3) months following such termination of employment (and assuming for this purpose only) had Executive continued to be employed by the Company, shall thereupon immediately vest and become immediately exercisable. Notwithstanding anything to the contrary contained in any Option Agreement, Executive’s option to purchase vested Option Shares shall be exercisable for the entire ten (10) year term of the option in accordance with Section 4 of the Option Agreement. For the avoidance of doubt, the 90 day post-termination of employment exercise period shall not be applicable to the exercise of the Option Shares as provided above.

(h) Parachute Payments. If Independent Tax Counsel (as that term is defined below) determines that the aggregate payments and benefits provided or to be provided to the Executive pursuant to this Agreement, and any other payments and benefits provided or to be provided to the Executive from the Company or any of its subsidiaries or other affiliates or any successors thereto constitute “parachute payments” as defined in Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”) (or any successor provision thereto) (“Parachute Payments”) that would be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then, except as otherwise provided in the next sentence, such Parachute Payments shall be reduced to the extent the Independent Tax Counsel shall determine is necessary (but not below zero) so that no portion thereof shall be subject to the Excise Tax. If Independent Tax Counsel determines that the Executive would receive in the aggregate greater payments and benefits on an after tax basis if the Parachute Payments were not reduced pursuant to this Section 2(h), then no such reduction shall be made. The determination of which payments or benefits shall be reduced to avoid the Excise Tax shall be made by the Independent Tax Counsel, provided that the Independent Tax Counsel shall reduce or eliminate, as the case may be, payments or benefits in the order that it determines will produce the required deduction in total Parachute Payments with the least reduction in economic value to the Executive of such payments. The determination of the Independent Tax Counsel under this Section 2(h) shall be final and binding on all parties hereto. For purposes of this Section 2(h), “Independent Tax Counsel” shall mean a lawyer, a certified public accountant with a nationally recognized accounting firm, or a compensation consultant with a nationally recognized actuarial and benefits consulting firm with expertise in the area of executive compensation tax law, who shall be selected by the Board, and whose fees and disbursements shall be paid by the Company.

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(i) Severance and Release. The Executive’s right to receive payment of the Severance Amount shall be contingent upon the Executive’s execution and non-revocation (other than in the case of Executive’s death) within forty-five (45) days of his date of termination of a general release reasonably satisfactory to the Company releasing the Company, its officers, agents, stockholders, and affiliates from any liability for any matter other than for payments under this Agreement and contractual obligations under other written agreements which form shall be provided to the Executive on or prior to his date of termination (the “Release”). The Company hereby agrees that upon the lapse of the period for revocation, if the Executive has not exercised his revocation right, the Company will execute a counterpart of the Release and deliver it to Executive forthwith. The payment of the Severance Amount shall commence within the sixty (60) day period following the Executive’s date of termination; provided that if a new calendar year commences during this period, the payments shall commence no earlier than January 2 of such new calendar year. The first payment after execution of the Release shall include all amounts that would have been paid following the date of termination had the Release been effective immediately following the date of termination but which were not yet paid.

4. Representations and Warranties of the Executive. Executive hereby represents and warrants to the Company that:

(a) The Executive:

(i) has not been convicted within the last five (5) years of any felony or misdemeanor in connection with the offer, purchase, or sale of any security or any felony involving fraud or deceit, including, but not limited to, forgery, embezzlement, obtaining money under false pretenses, larceny, or conspiracy to defraud;

(ii) is not currently subject to any state administrative enforcement order or judgment entered by a state securities administrator within the last five (5) years and is not subject to any state’s administrative enforcement order or judgment in which fraud or deceit (including, but not limited to, making untrue statements of material facts and omitting to state material facts) was found in which the order or judgment was entered within the last five (5) years; and

(iii) is a citizen of the United States of America and resident of the Commonwealth of Massachusetts.

(b) This Agreement constitutes the legal, valid and binding obligations of the Executive, enforceable in accordance with its terms, and the execution, delivery and performance of this Agreement by the Executive does not and will not conflict with, violate or cause a breach of any agreement, contract or instrument to which the Executive is a party or any judgment, order or decree to which the Executive is subject.

5. Representations and Warranties of the Company. The Company hereby represents and warrants to the Executive that:

(a) The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite corporate power and authority to carry out the transactions contemplated by this Agreement.

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(b) The execution, delivery and performance of this Agreement has been duly authorized by the Company. This Agreement constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Agreement, and the fulfillment of and compliance with the respective terms hereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice to any court or administrative or governmental body pursuant to, the charter or bylaws of the Company, or any law, statute, rule or regulation to which the Company is subject, or any agreement, instrument, order, judgment or decree to which the Company is subject.

6. Related Agreement. The Executive hereby reaffirms, confirms and approves each Related Agreement as a binding obligation of the Executive, enforceable in accordance with its terms. The Executive acknowledges and agrees that any Base Salary and/or Performance Bonus paid to the Executive pursuant to this Agreement shall serve as additional consideration for the Executive’s obligations under each Related Agreement.

7. Notices. All notices, demands or other communications to be given or delivered under or by reason of the provisions of this Agreement will be in writing and will be deemed to have been given when delivered personally, mailed by certified or registered mail, return receipt requested and postage prepaid, or sent via a nationally recognized overnight courier, or sent via facsimile to the recipient with a confirmation of receipt and accompanied by a certified or registered mailing. Such notices, demands and other communications will be sent to the address indicated below:

To the Company:

Aspen Aerogels, Inc.

30 Forbes Road

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: President and CEO

with copies (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 239-0100

Facsimile: (617) 227-4420

Attention: Christopher W. Nelson

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To the Executive:

Address specified on signature page

or to such other address or to the attention of such other person as the recipient party has specified by prior written notice to the sending party.

8. Miscellaneous.

(a) Severability. Whenever possible, each provision of this Agreement will be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any jurisdiction, such invalidity, illegality or unenforceability will not affect any other provision or any other jurisdiction, but this Agreement will be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or unenforceable provision had never been contained herein.

(b) Complete Agreement. This Agreement and the agreements referred to herein (including, without limitation, each Related Agreement) embody the complete agreement and understanding among the parties and supersede and preempt any prior understandings, agreements or representations by or among the parties, written or oral, which may have related to the subject matter hereof.

(c) Waiver of Jury Trial. The parties to this Agreement each hereby waives, to the fullest extent permitted by law, any right to trial by jury of any claim, demand, action, or cause of action (i) arising under this Agreement or (ii) in any way connected with or related or incidental to the dealings of the parties hereto in respect of this Agreement or any of the transactions related hereto, in each case whether now existing or hereafter arising, and whether in contract, tort, equity, or otherwise. The parties to this Agreement each hereby agrees and consents that any such claim, demand, action, or cause of action shall be decided by court trial without a jury and that the parties to this Agreement may file an original counterpart or a copy of this Agreement with any court as written evidence of the consent of the parties hereto to the waiver of their right to trial by jury.

(d) Counterparts; Facsimile Transmission. This Agreement may be executed simultaneously in two or more counterparts, any one of which need not contain the signatures of more than one party, but all such counterparts taken together will constitute one and the same Agreement. This Agreement may also be executed and delivered by facsimile transmission.

(e) Successors and Assigns. The provisions hereof shall inure to the benefit of, and be binding upon and assignable to, successors of the Company by way of merger, consolidation or sale. The Executive may not assign or delegate to any third person the Executive’s obligations under this Agreement. The rights and benefits of the Executive under this Agreement are personal to him and no such right or benefit shall be subject to voluntary or involuntary alienation, assignment or transfer. The Company shall require any successor (whether direct or indirect, by purchase, merger, consolidation or otherwise) to all or substantially all of the business and/or assets of the Company expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would have been required to perform it if no such succession had taken place. As used in this Agreement, “the Company” shall mean both the Company as defined above and any such successor that assumes and agrees to perform this Agreement, by operation of law or otherwise.

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(f) Governing Law. All issues concerning this Agreement shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflict of law provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the application of the law of any jurisdiction other than the Commonwealth of Massachusetts.

(g) Remedies. The parties hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and that any party may in its sole discretion apply to any court of law or equity of competent jurisdiction (without posting any bond or deposit) for specific performance and/or injunctive or other relief in order to enforce or prevent any violations of the provisions of this Agreement.

(h) Amendment and Waiver. The provisions of this Agreement may be amended and waived only with the prior written consent of the Company and the Executive.

(i) Certain Expenses. The Company agrees to pay, as incurred, to the fullest extent permitted by law, or indemnify the Executive if such payment is not legally permitted, for all legal fees and expenses that the Executive may in good faith incur as a result of any contest by the Company, the Executive or others of the validity or enforceability of or liability under, or otherwise involving, any provision of this Agreement; provided, however, that the Executive shall reimburse the Company for all such payments made by the Company in connection with a contest by the Company if a court of competent jurisdiction or an arbitrator shall find that the Executive did not act in good faith in connection with such contest.

(j) Compliance with Code Section 409A. To the extent that any payment under this Agreement constitutes “nonqualified deferred compensation” for purposes of Section 409A of the Internal Revenue Code of 1986, as amended (the “Code”), (i) a termination of employment shall not be deemed to have occurred for purposes of any provision of this Agreement providing for the payment of any amounts or benefits upon or following a termination of employment unless such termination is also a “separation from service” within the meaning of Code Section 409A and, for purposes of any such provision of this Agreement, references to a “termination ,” “termination of employment” or like terms shall mean “separation from service,” (ii) the Executive’s right to receive any installment payments pursuant to this Agreement shall be treated as a right to receive a series of separate and distinct payments, and (iii) if the Executive is deemed on the date of termination to be a “specified employee” within the meaning of that term under Code Section 409A(a)(2)(B), then with regard to any payment or the provision of any benefit that is considered deferred compensation under Code Section 409A payable on account of a “separation from service,” such payment or benefit shall be made or provided at the date which is the earlier of (A) the expiration of the six (6)-month period measured from the date of such “separation from service” of Executive, and (B) the date of Executive’s death, to the extent required under Code Section 409A. Upon the expiration of the foregoing delay period, all payments and benefits delayed pursuant to this Section 7(j) (whether they would have otherwise been payable in a single sum or in installments in the absence of such delay) shall be paid in a lump sum, and any remaining payments and benefits due under this Agreement shall be paid or provided in accordance with the normal payment dates specified for them herein.

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(k) Survival. The provisions of Sections 1, 2 and 5 through 7 of this Agreement shall survive any termination of this Agreement in accordance with the terms of such sections.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first above written.

THE COMPANY: ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
	Name: Donald R. Young
	Title: President & Chief Executive Officer
THE EXECUTIVE:
/s/ John Fairbanks
John Fairbanks
1 Gifford Drive Westford, MA 01886 Telephone: (978) 392-4969

[Signature Page to Fairbanks Executive Agreement]

FIRST AMENDMENT

TO

EXECUTIVE AGREEMENT

This First Amendment to the Amended and Restated Executive Agreement dated August 5, 2011 (the “Agreement”), by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and John Fairbanks (the “Executive”) is made effective as of November 6, 2012.

RECITALS

WHEREAS, the parties desire to amend the Agreement to revise the severance of the Executive and to make other clarifying changes, and

WHEREAS, the Board of Directors of the Company has approved the terms of this Amendment;

NOW THEREFORE, the Company and the Executive do hereby amend this Agreement as follows:

W I T N E S S E T H

1. Section 1 Definition of “Change of Control” is hereby amended in its entirety by deleting and replacing the current language with the following:

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which is a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized for its general corporate

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purposes (including without limitation the retirement or repayment of outstanding debt obligations), or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person,

2. Section 2(d) is hereby amended by replacing the phrase “three (3) months” with the phrase “six (6) months” each time it appears in such section.

3. This First Amendment shall be made part of the Agreement and all other terms and conditions as set forth in the Agreement shall remain unchanged, except as modified pursuant to the terms of this First Amendment.

[Signature Page Follows]

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IN WITNESS WHEREOF, the parties have executed this First Amendment as of the day and year first above written.

THE COMPANY:
ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
Name:	Donald R. Young
Title:	Chief Executive Officer
THE EXECUTIVE:
By:	/s/ John Fairbanks
John Fairbanks

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EX-10.12

Exhibit 10.12

EXECUTIVE AGREEMENT

This Amended and Restated Executive Agreement (this “Agreement”) is dated as of August 5, 2011, by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and George Gould (the “Executive”).

Recitals:

A. The Company and the Executive previously entered into an employment agreement dated as of March 17, 2010.

B. The Company and the Executive desire to amend and restate that agreement in the form of this Agreement to provide for the terms and conditions of the Executive’s employment with the Company.

Agreement:

NOW, THEREFORE, the parties hereto agree as follows:

1. Definitions. As used herein, the following terms shall have the following meanings.

“Board” means the Company’s board of directors.

“Cause” means: (i) willful misconduct, dishonesty, fraud or breach of fiduciary duty to the Company; (ii) deliberate disregard of the lawful rules or policies of the Company, or breach of an employment or other agreement with the Company, which results in direct or indirect loss, damage or injury to the Company; (iii) the unauthorized disclosure of any trade secret or confidential information of the Company; or (iv) the commission of an act which constitutes unfair competition with the Company or which induces any customer or supplier to breach a contract with the Company. For purposes hereof, whether or not the Executive has committed an act or omission of the type referred to in subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Company of the Executive’s employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Cause for purposes of this Agreement.

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which was a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized by the Company for its general corporate purposes or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person.

“Good Reason” means: (i) any material breach by the Company of this Agreement that is not cured by the Company within thirty (30) days after written notice specifying in reasonable detail the nature of such material breach is provided to the Company by the Executive; (ii) the demotion of the Executive such that the Executive no longer serves in the position specified in Section 2(a)(i) below or a material reduction in the Executive’s current duties and authority in the position specified in Section 2(a)(i) below, in each case, without his consent; (iii) the written demand by the Company for the Executive to relocate or commute more than 40 miles from Northborough, Massachusetts without his consent; or (iv) any reduction by the Company in the Executive’s Base Salary without his consent. For purposes hereof, whether or not the Executive has Good Reason to terminate his employment by the Company pursuant to subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Executive of his employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Good Reason for purposes of this Agreement.

“Permanent Disability” means the Executive is unable to perform, by reason of physical or mental incapacity, his then duties or obligations to the Company, for a total period of one hundred eighty (180) days in any three hundred sixty (360) day period.

“Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

“Related Agreement” means any confidentiality, non-competition, intellectual property assignment or similar agreement by and between the Executive and the Company, whether entered into on or prior to the date of the Agreement or entered into subsequent to the date of the Agreement.

2. Employment. The Company agrees to employ the Executive, and the Executive hereby accepts employment with the Company consistent with the Executive’s position and duties, upon the terms and conditions set forth in this Agreement for the period beginning on the date hereof and ending as provided in Section 2(c) (the “Employment Period”).

(a) Position and Duties.

(i) During the Employment Period, the Executive shall serve as Vice President, Research and Development of the Company and shall have the duties, responsibilities and authority consistent with such position that are designated by the President, subject to the direction and supervision of the President.

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(ii) The Executive shall devote his best efforts and his full business time and attention (except for permitted vacation periods and reasonable periods of illness or other incapacity) to the business and affairs of the Company. The Executive shall perform his duties and responsibilities to the best of his abilities in a diligent, trustworthy, businesslike and efficient manner. Notwithstanding the foregoing, the Executive may, to the extent not otherwise prohibited by this Agreement, devote such amount of time as does not interfere or compete with the performance of the Executive’s duties under this Agreement to any one or more of the following activities: (i) engaging in charitable activities, including serving on the boards of directors of charitable organizations or (ii) serving on the board of directors of any other company with the prior written approval of the Company.

(b) Salary and Benefits.

(i) During the Employment Period, the Executive’s base salary shall be $184,000 per year (such annual salary, as it may be adjusted upward by the Board or a committee thereof in its discretion, being referred to as the “Base Salary”). The Base Salary shall be payable in regular installments in accordance with the Company’s general payroll practices, shall be subject to customary withholding and may be increased (but not decreased) at the discretion of the Board or a committee thereof.

(ii) In addition to the Base Salary, Executive shall be eligible to receive an annual cash incentive bonus payment (each, a “Performance Bonus”) in an amount, if any, to be determined by the Company’s Board or a committee thereof.

(iii) The Company will reimburse the Executive for all reasonable travel and other expenses incurred by the Executive in connection with the performance of his duties and obligations under this Agreement. The Executive shall comply with such reasonable limitations and reporting requirements with respect to expenses as may be established by the Company from time to time.

(iv) In addition, the Executive will be entitled to participate in all compensation or employee benefit plans or programs and receive all benefits and perquisites for which salaried employees of the Company generally are eligible under any plan or program now or established later by the Company on the same basis as similarly situated senior executives of the Company. The Executive will participate to the extent permissible under the terms and provisions of such plans or programs, in accordance with program provisions. Nothing in this Agreement will preclude the Company from amending or terminating any of the plans or programs applicable to salaried employees or senior executives of the Company as long as such amendment or termination is applicable to all salaried employees or senior executives, as the case may be, so long as such plans or programs are replaced with plans no less favorable, in the aggregate, than existing plans.

(c) Employment at Will. The Executive and the Company understand and agree that the Executive is an employee at will, and that the Executive may resign, or the Company may terminate the Executive’s employment, at any time and for any or for no reason. Nothing in this Agreement shall be construed to alter the at-will nature of the Executive’s employment, nor shall anything in this Agreement be construed as providing the Executive with a definite term of employment.

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(d) Severance. If the Executive’s employment with the Company is terminated (i) by the Company without Cause; or (ii) by the Executive for Good Reason within thirty (30) days after the occurrence of an event constituting Good Reason (including the expiration of any applicable cure periods), the Executive shall be entitled to receive an amount equal to the Executive’s Base Salary (prior to any reduction) for three (3) months following the date of such termination, be entitled to continued participation on substantially similar terms in all employee benefit plans and programs to which he was entitled to participate in as of the date of such termination for three (3) months following the date of such termination, and shall be entitled to receive any accrued but unpaid bonuses or commissions then owed or fully earned by the Executive in accordance with Section 2(b)(ii) above (collectively, the “Severance Amount”). All amounts payable to the Executive pursuant to this provision shall be payable in regular installments in accordance with the Company’s regular payroll practices and subject to customary withholding. The Executive hereby agrees that no severance compensation shall be payable upon termination of the Executive’s employment with the Company (i) by the Company with Cause; (ii) by the Executive without Good Reason; or (iii) as a result of the Executive’s death or Permanent Disability, and the Executive hereby waives any claim for severance compensation except as set forth in this Section 2(d).

(e) Termination or Reduction of Severance. If at any time after termination of employment hereunder the Executive breaches any of the provisions set forth in any Related Agreement, and if the Executive fails to cure each such breach, in all material respects, within thirty (30) days after the Company has given to the Executive written notice of such breach, the Company shall no longer be obligated to make any payments of the Severance Amount pursuant to Section 2(d) above.

(f) Change of Control. In addition to the provisions of Section 2(d), if a “Change of Control” occurs and the Executive does not receive an offer to remain employed by the Company in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms (including severance and termination provisions) as contained herein for at least two years, and the Executive is terminated without Cause or resigns for any reason within the two year period following the Change of Control event, the Executive shall be entitled upon his termination of employment to receive the Severance Amount payable in accordance with the provisions of Section 2(d).

(g) Options. Reference is hereby made to that certain Incentive Stock Option Agreement dated November 11, 2009 by and between the Company and the Executive (the “Option Agreement”) pursuant to which the Executive was granted an option to purchase certain shares of the Company’s common stock (the “Option Shares”). This paragraph shall be deemed by each of the Company and the Executive to be a corrective amendment to the Option Agreement to reflect the approved terms as of the date of grant and shall supplement and supercede any contrary terms therein. In addition, in the event that the Executive should after March 17, 2010 receive any additional grants of stock options or restricted stock awards, this paragraph shall be deemed by each of the Company and the Executive to be an amendment to the agreement or agreements pursuant to which any such stock options or restricted stock awards may be granted and shall supplement and supercede any contrary terms therein (and any reference to “Option Agreement” or “Option Shares” below shall be deemed to include any such later granted stock options or restricted stock awards). Upon the (i) consummation of a Change

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of Control transaction, unless the Executive receives an offer to remain employed by the Company in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms as contained herein for at least two years following the Change of Control event; or (ii) termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time during the two (2) year period following the consummation of a Change of Control transaction, any and all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. In addition, if upon a merger, consolidation or sale of all or substantially all of the Company’s assets (a “Corporate Transaction”) the Option Shares do not continue in the form of equity in the successor or acquiring entity such that vesting may continue to accrue after the Corporate Transaction then immediately prior to such Corporate Transaction all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. Upon a termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time after March 17, 2011, a number of unvested Option Shares as would have vested in the three (3) months following such termination of employment (and assuming for this purpose only) had Executive continued to be employed by the Company, shall thereupon immediately vest and become immediately exercisable. Notwithstanding anything to the contrary contained in any Option Agreement, Executive’s option to purchase vested Option Shares shall be exercisable for the entire ten (10) year term of the option in accordance with Section 4 of the Option Agreement. For the avoidance of doubt, the 90 day post-termination of employment exercise period shall not be applicable to the exercise of the Option Shares as provided above.

(h) Parachute Payments. If Independent Tax Counsel (as that term is defined below) determines that the aggregate payments and benefits provided or to be provided to the Executive pursuant to this Agreement, and any other payments and benefits provided or to be provided to the Executive from the Company or any of its subsidiaries or other affiliates or any successors thereto constitute “parachute payments” as defined in Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”) (or any successor provision thereto) (“Parachute Payments”) that would be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then, except as otherwise provided in the next sentence, such Parachute Payments shall be reduced to the extent the Independent Tax Counsel shall determine is necessary (but not below zero) so that no portion thereof shall be subject to the Excise Tax. If Independent Tax Counsel determines that the Executive would receive in the aggregate greater payments and benefits on an after tax basis if the Parachute Payments were not reduced pursuant to this Section 2(h), then no such reduction shall be made. The determination of which payments or benefits shall be reduced to avoid the Excise Tax shall be made by the Independent Tax Counsel, provided that the Independent Tax Counsel shall reduce or eliminate, as the case may be, payments or benefits in the order that it determines will produce the required deduction in total Parachute Payments with the least reduction in economic value to the Executive of such payments. The determination of the Independent Tax Counsel under this Section 2(h) shall be final and binding on all parties hereto. For purposes of this Section 2(h), “Independent Tax Counsel” shall mean a lawyer, a certified public accountant with a nationally recognized accounting firm, or a compensation consultant with a nationally recognized actuarial and benefits consulting firm with expertise in the area of executive compensation tax law, who shall be selected by the Board, and whose fees and disbursements shall be paid by the Company.

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(i) Severance and Release. The Executive’s right to receive payment of the Severance Amount shall be contingent upon the Executive’s execution and non-revocation (other than in the case of Executive’s death) within forty-five (45) days of his date of termination of a general release reasonably satisfactory to the Company releasing the Company, its officers, agents, stockholders, and affiliates from any liability for any matter other than for payments under this Agreement and contractual obligations under other written agreements which form shall be provided to the Executive on or prior to his date of termination (the “Release”). The Company hereby agrees that upon the lapse of the period for revocation, if the Executive has not exercised his revocation right, the Company will execute a counterpart of the Release and deliver it to Executive forthwith. The payment of the Severance Amount shall commence within the sixty (60) day period following the Executive’s date of termination; provided that if a new calendar year commences during this period, the payments shall commence no earlier than January 2 of such new calendar year. The first payment after execution of the Release shall include all amounts that would have been paid following the date of termination had the Release been effective immediately following the date of termination but which were not yet paid.

3. Representations and Warranties of the Executive. Executive hereby represents and warrants to the Company that:

(a) The Executive:

(i) has not been convicted within the last five (5) years of any felony or misdemeanor in connection with the offer, purchase, or sale of any security or any felony involving fraud or deceit, including, but not limited to, forgery, embezzlement, obtaining money under false pretenses, larceny, or conspiracy to defraud;

(ii) is not currently subject to any state administrative enforcement order or judgment entered by a state securities administrator within the last five (5) years and is not subject to any state’s administrative enforcement order or judgment in which fraud or deceit (including, but not limited to, making untrue statements of material facts and omitting to state material facts) was found in which the order or judgment was entered within the last five (5) years; and

(iii) is a citizen of the United States of America and resident of the Commonwealth of Massachusetts.

(b) This Agreement constitutes the legal, valid and binding obligations of the Executive, enforceable in accordance with its terms, and the execution, delivery and performance of this Agreement by the Executive does not and will not conflict with, violate or cause a breach of any agreement, contract or instrument to which the Executive is a party or any judgment, order or decree to which the Executive is subject.

4. Representations and Warranties of the Company. The Company hereby represents and warrants to the Executive that:

(a) The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite corporate power and authority to carry out the transactions contemplated by this Agreement.

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(b) The execution, delivery and performance of this Agreement has been duly authorized by the Company. This Agreement constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Agreement, and the fulfillment of and compliance with the respective terms hereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice to any court or administrative or governmental body pursuant to, the charter or bylaws of the Company, or any law, statute, rule or regulation to which the Company is subject, or any agreement, instrument, order, judgment or decree to which the Company is subject.

5. Related Agreement. The Executive hereby reaffirms, confirms and approves each Related Agreement as a binding obligation of the Executive, enforceable in accordance with its terms. The Executive acknowledges and agrees that any Base Salary and/or Performance Bonus paid to the Executive pursuant to this Agreement shall serve as additional consideration for the Executive’s obligations under each Related Agreement.

6. Notices. All notices, demands or other communications to be given or delivered under or by reason of the provisions of this Agreement will be in writing and will be deemed to have been given when delivered personally, mailed by certified or registered mail, return receipt requested and postage prepaid, or sent via a nationally recognized overnight courier, or sent via facsimile to the recipient with a confirmation of receipt and accompanied by a certified or registered mailing. Such notices, demands and other communications will be sent to the address indicated below:

To the Company:

Aspen Aerogels, Inc.

30 Forbes Road

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: President and CEO

with copies (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 239-0100

Facsimile: (617) 227-4420

Attention: Christopher W. Nelson

To the Executive:

Address specified on signature page

or to such other address or to the attention of such other person as the recipient party has specified by prior written notice to the sending party.

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7. Miscellaneous.

(a) Severability. Whenever possible, each provision of this Agreement will be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any jurisdiction, such invalidity, illegality or unenforceability will not affect any other provision or any other jurisdiction, but this Agreement will be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or unenforceable provision had never been contained herein.

(b) Complete Agreement. This Agreement and the agreements referred to herein (including, without limitation, each Related Agreement) embody the complete agreement and understanding among the parties and supersede and preempt any prior understandings, agreements or representations by or among the parties, written or oral, which may have related to the subject matter hereof.

(c) Waiver of Jury Trial. The parties to this Agreement each hereby waives, to the fullest extent permitted by law, any right to trial by jury of any claim, demand, action, or cause of action (i) arising under this Agreement or (ii) in any way connected with or related or incidental to the dealings of the parties hereto in respect of this Agreement or any of the transactions related hereto, in each case whether now existing or hereafter arising, and whether in contract, tort, equity, or otherwise. The parties to this Agreement each hereby agrees and consents that any such claim, demand, action, or cause of action shall be decided by court trial without a jury and that the parties to this Agreement may file an original counterpart or a copy of this Agreement with any court as written evidence of the consent of the parties hereto to the waiver of their right to trial by jury.

(d) Counterparts; Facsimile Transmission. This Agreement may be executed simultaneously in two or more counterparts, any one of which need not contain the signatures of more than one party, but all such counterparts taken together will constitute one and the same Agreement. This Agreement may also be executed and delivered by facsimile transmission.

(e) Successors and Assigns. The provisions hereof shall inure to the benefit of, and be binding upon and assignable to, successors of the Company by way of merger, consolidation or sale. The Executive may not assign or delegate to any third person the Executive’s obligations under this Agreement. The rights and benefits of the Executive under this Agreement are personal to him and no such right or benefit shall be subject to voluntary or involuntary alienation, assignment or transfer. The Company shall require any successor (whether direct or indirect, by purchase, merger, consolidation or otherwise) to all or substantially all of the business and/or assets of the Company expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would have been required to perform it if no such succession had taken place. As used in this Agreement, “the Company” shall mean both the Company as defined above and any such successor that assumes and agrees to perform this Agreement, by operation of law or otherwise.

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(f) Governing Law. All issues concerning this Agreement shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflict of law provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the application of the law of any jurisdiction other than the Commonwealth of Massachusetts.

(g) Remedies. The parties hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and that any party may in its sole discretion apply to any court of law or equity of competent jurisdiction (without posting any bond or deposit) for specific performance and/or injunctive or other relief in order to enforce or prevent any violations of the provisions of this Agreement.

(h) Amendment and Waiver. The provisions of this Agreement may be amended and waived only with the prior written consent of the Company and the Executive.

(i) Certain Expenses. The Company agrees to pay, as incurred, to the fullest extent permitted by law, or indemnify the Executive if such payment is not legally permitted, for all legal fees and expenses that the Executive may in good faith incur as a result of any contest by the Company, the Executive or others of the validity or enforceability of or liability under, or otherwise involving, any provision of this Agreement; provided, however, that the Executive shall reimburse the Company for all such payments made by the Company in connection with a contest by the Company if a court of competent jurisdiction or an arbitrator shall find that the Executive did not act in good faith in connection with such contest.

(j) Compliance with Code Section 409A. To the extent that any payment under this Agreement constitutes “nonqualified deferred compensation” for purposes of Section 409A of the Internal Revenue Code of 1986, as amended (the “Code”), (i) a termination of employment shall not be deemed to have occurred for purposes of any provision of this Agreement providing for the payment of any amounts or benefits upon or following a termination of employment unless such termination is also a “separation from service” within the meaning of Code Section 409A and, for purposes of any such provision of this Agreement, references to a “termination ,” “termination of employment” or like terms shall mean “separation from service,” (ii) the Executive’s right to receive any installment payments pursuant to this Agreement shall be treated as a right to receive a series of separate and distinct payments, and (iii) if the Executive is deemed on the date of termination to be a “specified employee” within the meaning of that term under Code Section 409A(a)(2)(B), then with regard to any payment or the provision of any benefit that is considered deferred compensation under Code Section 409A payable on account of a “separation from service,” such payment or benefit shall be made or provided at the date which is the earlier of (A) the expiration of the six (6)-month period measured from the date of such “separation from service” of Executive, and (B) the date of Executive’s death, to the extent required under Code Section 409A. Upon the expiration of the foregoing delay period, all payments and benefits delayed pursuant to this Section 7(j) (whether they would have otherwise been payable in a single sum or in installments in the absence of such delay) shall be paid in a lump sum, and any remaining payments and benefits due under this Agreement shall be paid or provided in accordance with the normal payment dates specified for them herein.

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(k) Survival. The provisions of Sections 1, 2 and 5 through 7 of this Agreement shall survive any termination of this Agreement in accordance with the terms of such sections.

[REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first above written.

	THE COMPANY: ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
Name:	John F. Fairbanks
Title:	Chief Financial Officer
	THE EXECUTIVE:
	/s/ George Gould
	George Gould
	174 Millville Road Mendon, MA 01756 Telephone: (508) 748-5194

[Signature Page Gould Executive Agreement]

EX-10.13

Exhibit 10.13

EXECUTIVE AGREEMENT

This Amended and Restated Executive Agreement (this “Agreement”) is dated as of August 5, 2011, by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and Kevin Schmidt (the “Executive”).

Recitals:

A. The Company and the Executive previously entered into an employment agreement dated as of March 17, 2010.

B. The Company and the Executive desire to amend and restate that agreement in the form of this Agreement to provide for the terms and conditions of the Executive’s employment with the Company.

Agreement:

NOW, THEREFORE, the parties hereto agree as follows:

1. Definitions. As used herein, the following terms shall have the following meanings.

“Board” means the Company’s board of directors.

“Cause” means: (i) willful misconduct, dishonesty, fraud or breach of fiduciary duty to the Company; (ii) deliberate disregard of the lawful rules or policies of the Company, or breach of an employment or other agreement with the Company, which results in direct or indirect loss, damage or injury to the Company; (iii) the unauthorized disclosure of any trade secret or confidential information of the Company; or (iv) the commission of an act which constitutes unfair competition with the Company or which induces any customer or supplier to breach a contract with the Company. For purposes hereof, whether or not the Executive has committed an act or omission of the type referred to in subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Company of the Executive’s employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Cause for purposes of this Agreement.

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which was a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized by the Company for its general corporate purposes or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person.

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“Good Reason” means: (i) any material breach by the Company of this Agreement that is not cured by the Company within thirty (30) days after written notice specifying in reasonable detail the nature of such material breach is provided to the Company by the Executive; (ii) the demotion of the Executive such that the Executive no longer serves in the position specified in Section 2(a)(i) below or a material reduction in the Executive’s current duties and authority in the position specified in Section 2(a)(i) below, in each case, without his consent; (iii) the written demand by the Company for the Executive to relocate or commute more than 40 miles from Northborough, Massachusetts without his consent; or (iv) any reduction by the Company in the Executive’s Base Salary without his consent. For purposes hereof, whether or not the Executive has Good Reason to terminate his employment by the Company pursuant to subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Executive of his employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Good Reason for purposes of this Agreement.

“Permanent Disability” means the Executive is unable to perform, by reason of physical or mental incapacity, his then duties or obligations to the Company, for a total period of one hundred eighty (180) days in any three hundred sixty (360) day period.

“Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

“Related Agreement” means any confidentiality, non-competition, intellectual property assignment or similar agreement by and between the Executive and the Company, whether entered into on or prior to the date of the Agreement or entered into subsequent to the date of the Agreement.

2. Employment. The Company agrees to employ the Executive, and the Executive hereby accepts employment with the Company consistent with the Executive’s position and duties, upon the terms and conditions set forth in this Agreement for the period beginning on the date hereof and ending as provided in Section 2(c) (the “Employment Period”).

(a) Position and Duties.

(i) During the Employment Period, the Executive shall serve as Vice President, Operations of the Company and shall have the duties, responsibilities and authority consistent with such position that are designated by the President, subject to the direction and supervision of the President.

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(ii) The Executive shall devote his best efforts and his full business time and attention (except for permitted vacation periods and reasonable periods of illness or other incapacity) to the business and affairs of the Company. The Executive shall perform his duties and responsibilities to the best of his abilities in a diligent, trustworthy, businesslike and efficient manner. Notwithstanding the foregoing, the Executive may, to the extent not otherwise prohibited by this Agreement, devote such amount of time as does not interfere or compete with the performance of the Executive’s duties under this Agreement to any one or more of the following activities: (i) engaging in charitable activities, including serving on the boards of directors of charitable organizations or (ii) serving on the board of directors of any other company with the prior written approval of the Company.

(b) Salary and Benefits.

(i) During the Employment Period, the Executive’s base salary shall be $265,300 per year (such annual salary, as it may be adjusted upward by the Board or a committee thereof in its discretion, being referred to as the “Base Salary”). The Base Salary shall be payable in regular installments in accordance with the Company’s general payroll practices, shall be subject to customary withholding and may be increased (but not decreased) at the discretion of the Board or a committee thereof.

(ii) In addition to the Base Salary, Executive shall be eligible to receive an annual cash incentive bonus payment (each, a “Performance Bonus”) in an amount, if any, to be determined by the Company’s Board or a committee thereof.

(iii) The Company will reimburse the Executive for all reasonable travel and other expenses incurred by the Executive in connection with the performance of his duties and obligations under this Agreement. The Executive shall comply with such reasonable limitations and reporting requirements with respect to expenses as may be established by the Company from time to time.

(iv) In addition, the Executive will be entitled to participate in all compensation or employee benefit plans or programs and receive all benefits and perquisites for which salaried employees of the Company generally are eligible under any plan or program now or established later by the Company on the same basis as similarly situated senior executives of the Company. The Executive will participate to the extent permissible under the terms and provisions of such plans or programs, in accordance with program provisions. Nothing in this Agreement will preclude the Company from amending or terminating any of the plans or programs applicable to salaried employees or senior executives of the Company as long as such amendment or termination is applicable to all salaried employees or senior executives, as the case may be, so long as such plans or programs are replaced with plans no less favorable, in the aggregate, than existing plans.

(c) Employment at Will. The Executive and the Company understand and agree that the Executive is an employee at will, and that the Executive may resign, or the Company may terminate the Executive’s employment, at any time and for any or for no reason. Nothing in this Agreement shall be construed to alter the at-will nature of the Executive’s employment, nor shall anything in this Agreement be construed as providing the Executive with a definite term of employment.

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(d) Severance. If the Executive’s employment with the Company is terminated (i) by the Company without Cause; or (ii) by the Executive for Good Reason within thirty (30) days after the occurrence of an event constituting Good Reason (including the expiration of any applicable cure periods), the Executive shall be entitled to receive an amount equal to the Executive’s Base Salary (prior to any reduction) for three (3) months following the date of such termination, be entitled to continued participation on substantially similar terms in all employee benefit plans and programs to which he was entitled to participate in as of the date of such termination for three (3) months following the date of such termination, and shall be entitled to receive any accrued but unpaid bonuses or commissions then owed or fully earned by the Executive in accordance with Section 2(b)(ii) above (collectively, the “Severance Amount”). All amounts payable to the Executive pursuant to this provision shall be payable in regular installments in accordance with the Company’s regular payroll practices and subject to customary withholding. The Executive hereby agrees that no severance compensation shall be payable upon termination of the Executive’s employment with the Company (i) by the Company with Cause; (ii) by the Executive without Good Reason; or (iii) as a result of the Executive’s death or Permanent Disability, and the Executive hereby waives any claim for severance compensation except as set forth in this Section 2(d).

(e) Termination or Reduction of Severance. If at any time after termination of employment hereunder the Executive breaches any of the provisions set forth in any Related Agreement, and if the Executive fails to cure each such breach, in all material respects, within thirty (30) days after the Company has given to the Executive written notice of such breach, the Company shall no longer be obligated to make any payments of the Severance Amount pursuant to Section 2(d) above.

(f) Change of Control. In addition to the provisions of Section 2(d), if a “Change of Control” occurs and the Executive does not receive an offer to remain employed by the Company in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms (including severance and termination provisions) as contained herein for at least two years, and the Executive is terminated without Cause or resigns for any reason within the two year period following the Change of Control event, the Executive shall be entitled upon his termination of employment to receive the Severance Amount payable in accordance with the provisions of Section 2(d).

(g) Options. Reference is hereby made to that certain Incentive Stock Option Agreement dated November 11, 2009 by and between the Company and the Executive (the “Option Agreement”) pursuant to which the Executive was granted an option to purchase certain shares of the Company’s common stock (the “Option Shares”). This paragraph shall be deemed by each of the Company and the Executive to be a corrective amendment to the Option Agreement to reflect the approved terms as of the date of grant and shall supplement and supercede any contrary terms therein. In addition, in the event that the Executive should after March 17, 2010 receive any additional grants of stock options or restricted stock awards, this paragraph shall be deemed by each of the Company and the Executive to be an amendment to the agreement or agreements pursuant to which any such stock options or restricted stock awards may be granted and shall supplement and supercede any contrary terms therein (and any reference to “Option Agreement” or “Option Shares” below shall be deemed to include any such later granted stock options or restricted stock awards). Upon the (i) consummation of a Change

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of Control transaction, unless the Executive receives an offer to remain employed by the Company in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms as contained herein for at least two years following the Change of Control event; or (ii) termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time during the two (2) year period following the consummation of a Change of Control transaction, any and all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. In addition, if upon a merger, consolidation or sale of all or substantially all of the Company’s assets (a “Corporate Transaction”) the Option Shares do not continue in the form of equity in the successor or acquiring entity such that vesting may continue to accrue after the Corporate Transaction then immediately prior to such Corporate Transaction all then unvested Option Shares shall thereupon immediately vest and become immediately exercisable. Upon a termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time after March 17, 2011, a number of unvested Option Shares as would have vested in the three (3) months following such termination of employment (and assuming for this purpose only) had Executive continued to be employed by the Company, shall thereupon immediately vest and become immediately exercisable. Notwithstanding anything to the contrary contained in any Option Agreement, Executive’s option to purchase vested Option Shares shall be exercisable for the entire ten (10) year term of the option in accordance with Section 4 of the Option Agreement. For the avoidance of doubt, the 90 day post-termination of employment exercise period shall not be applicable to the exercise of the Option Shares as provided above.

(h) Parachute Payments. If Independent Tax Counsel (as that term is defined below) determines that the aggregate payments and benefits provided or to be provided to the Executive pursuant to this Agreement, and any other payments and benefits provided or to be provided to the Executive from the Company or any of its subsidiaries or other affiliates or any successors thereto constitute “parachute payments” as defined in Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”) (or any successor provision thereto) (“Parachute Payments”) that would be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then, except as otherwise provided in the next sentence, such Parachute Payments shall be reduced to the extent the Independent Tax Counsel shall determine is necessary (but not below zero) so that no portion thereof shall be subject to the Excise Tax. If Independent Tax Counsel determines that the Executive would receive in the aggregate greater payments and benefits on an after tax basis if the Parachute Payments were not reduced pursuant to this Section 2(h), then no such reduction shall be made. The determination of which payments or benefits shall be reduced to avoid the Excise Tax shall be made by the Independent Tax Counsel, provided that the Independent Tax Counsel shall reduce or eliminate, as the case may be, payments or benefits in the order that it determines will produce the required deduction in total Parachute Payments with the least reduction in economic value to the Executive of such payments. The determination of the Independent Tax Counsel under this Section 2(h) shall be final and binding on all parties hereto. For purposes of this Section 2(h), “Independent Tax Counsel” shall mean a lawyer, a certified public accountant with a nationally recognized accounting firm, or a compensation consultant with a nationally recognized actuarial and benefits consulting firm with expertise in the area of executive compensation tax law, who shall be selected by the Board, and whose fees and disbursements shall be paid by the Company.

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(i) Severance and Release. The Executive’s right to receive payment of the Severance Amount shall be contingent upon the Executive’s execution and non-revocation (other than in the case of Executive’s death) within forty-five (45) days of his date of termination of a general release reasonably satisfactory to the Company releasing the Company, its officers, agents, stockholders, and affiliates from any liability for any matter other than for payments under this Agreement and contractual obligations under other written agreements which form shall be provided to the Executive on or prior to his date of termination (the “Release”). The Company hereby agrees that upon the lapse of the period for revocation, if the Executive has not exercised his revocation right, the Company will execute a counterpart of the Release and deliver it to Executive forthwith. The payment of the Severance Amount shall commence within the sixty (60) day period following the Executive’s date of termination; provided that if a new calendar year commences during this period, the payments shall commence no earlier than January 2 of such new calendar year. The first payment after execution of the Release shall include all amounts that would have been paid following the date of termination had the Release been effective immediately following the date of termination but which were not yet paid.

3. Representations and Warranties of the Executive. Executive hereby represents and warrants to the Company that:

(a) The Executive:

(i) has not been convicted within the last five (5) years of any felony or misdemeanor in connection with the offer, purchase, or sale of any security or any felony involving fraud or deceit, including, but not limited to, forgery, embezzlement, obtaining money under false pretenses, larceny, or conspiracy to defraud;

(ii) is not currently subject to any state administrative enforcement order or judgment entered by a state securities administrator within the last five (5) years and is not subject to any state’s administrative enforcement order or judgment in which fraud or deceit (including, but not limited to, making untrue statements of material facts and omitting to state material facts) was found in which the order or judgment was entered within the last five (5) years; and

(iii) is a citizen of the United States of America and resident of the Commonwealth of Massachusetts.

(b) This Agreement constitutes the legal, valid and binding obligations of the Executive, enforceable in accordance with its terms, and the execution, delivery and performance of this Agreement by the Executive does not and will not conflict with, violate or cause a breach of any agreement, contract or instrument to which the Executive is a party or any judgment, order or decree to which the Executive is subject.

4. Representations and Warranties of the Company. The Company hereby represents and warrants to the Executive that:

(a) The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite corporate power and authority to carry out the transactions contemplated by this Agreement.

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(b) The execution, delivery and performance of this Agreement has been duly authorized by the Company. This Agreement constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Agreement, and the fulfillment of and compliance with the respective terms hereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice to any court or administrative or governmental body pursuant to, the charter or bylaws of the Company, or any law, statute, rule or regulation to which the Company is subject, or any agreement, instrument, order, judgment or decree to which the Company is subject.

5. Related Agreement. The Executive hereby reaffirms, confirms and approves each Related Agreement as a binding obligation of the Executive, enforceable in accordance with its terms. The Executive acknowledges and agrees that any Base Salary and/or Performance Bonus paid to the Executive pursuant to this Agreement shall serve as additional consideration for the Executive’s obligations under each Related Agreement.

6. Notices. All notices, demands or other communications to be given or delivered under or by reason of the provisions of this Agreement will be in writing and will be deemed to have been given when delivered personally, mailed by certified or registered mail, return receipt requested and postage prepaid, or sent via a nationally recognized overnight courier, or sent via facsimile to the recipient with a confirmation of receipt and accompanied by a certified or registered mailing. Such notices, demands and other communications will be sent to the address indicated below:

To the Company:

Aspen Aerogels, Inc.

30 Forbes Road

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: President and CEO

with copies (which shall not constitute notice) to:

Edwards Angell Palmer & Dodge LLP

111 Huntington Avenue

Boston, MA 02199

Telephone: (617) 239-0100

Facsimile: (617) 227-4420

Attention: Christopher W. Nelson

To the Executive:

Address specified on signature page

or to such other address or to the attention of such other person as the recipient party has specified by prior written notice to the sending party.

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7. Miscellaneous.

(a) Severability. Whenever possible, each provision of this Agreement will be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any jurisdiction, such invalidity, illegality or unenforceability will not affect any other provision or any other jurisdiction, but this Agreement will be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or unenforceable provision had never been contained herein.

(b) Complete Agreement. This Agreement and the agreements referred to herein (including, without limitation, each Related Agreement) embody the complete agreement and understanding among the parties and supersede and preempt any prior understandings, agreements or representations by or among the parties, written or oral, which may have related to the subject matter hereof.

(c) Waiver of Jury Trial. The parties to this Agreement each hereby waives, to the fullest extent permitted by law, any right to trial by jury of any claim, demand, action, or cause of action (i) arising under this Agreement or (ii) in any way connected with or related or incidental to the dealings of the parties hereto in respect of this Agreement or any of the transactions related hereto, in each case whether now existing or hereafter arising, and whether in contract, tort, equity, or otherwise. The parties to this Agreement each hereby agrees and consents that any such claim, demand, action, or cause of action shall be decided by court trial without a jury and that the parties to this Agreement may file an original counterpart or a copy of this Agreement with any court as written evidence of the consent of the parties hereto to the waiver of their right to trial by jury.

(d) Counterparts; Facsimile Transmission. This Agreement may be executed simultaneously in two or more counterparts, any one of which need not contain the signatures of more than one party, but all such counterparts taken together will constitute one and the same Agreement. This Agreement may also be executed and delivered by facsimile transmission.

(e) Successors and Assigns. The provisions hereof shall inure to the benefit of, and be binding upon and assignable to, successors of the Company by way of merger, consolidation or sale. The Executive may not assign or delegate to any third person the Executive’s obligations under this Agreement. The rights and benefits of the Executive under this Agreement are personal to him and no such right or benefit shall be subject to voluntary or involuntary alienation, assignment or transfer. The Company shall require any successor (whether direct or indirect, by purchase, merger, consolidation or otherwise) to all or substantially all of the business and/or assets of the Company expressly to assume and agree to perform this Agreement in the same manner and to the same extent that the Company would have been required to perform it if no such succession had taken place. As used in this Agreement, “the Company” shall mean both the Company as defined above and any such successor that assumes and agrees to perform this Agreement, by operation of law or otherwise.

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(f) Governing Law. All issues concerning this Agreement shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflict of law provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the application of the law of any jurisdiction other than the Commonwealth of Massachusetts.

(g) Remedies. The parties hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and that any party may in its sole discretion apply to any court of law or equity of competent jurisdiction (without posting any bond or deposit) for specific performance and/or injunctive or other relief in order to enforce or prevent any violations of the provisions of this Agreement.

(h) Amendment and Waiver. The provisions of this Agreement may be amended and waived only with the prior written consent of the Company and the Executive.

(i) Certain Expenses. The Company agrees to pay, as incurred, to the fullest extent permitted by law, or indemnify the Executive if such payment is not legally permitted, for all legal fees and expenses that the Executive may in good faith incur as a result of any contest by the Company, the Executive or others of the validity or enforceability of or liability under, or otherwise involving, any provision of this Agreement; provided, however, that the Executive shall reimburse the Company for all such payments made by the Company in connection with a contest by the Company if a court of competent jurisdiction or an arbitrator shall find that the Executive did not act in good faith in connection with such contest.

(j) Compliance with Code Section 409A. To the extent that any payment under this Agreement constitutes “nonqualified deferred compensation” for purposes of Section 409A of the Internal Revenue Code of 1986, as amended (the “Code”), (i) a termination of employment shall not be deemed to have occurred for purposes of any provision of this Agreement providing for the payment of any amounts or benefits upon or following a termination of employment unless such termination is also a “separation from service” within the meaning of Code Section 409A and, for purposes of any such provision of this Agreement, references to a “termination ,” “termination of employment” or like terms shall mean “separation from service,” (ii) the Executive’s right to receive any installment payments pursuant to this Agreement shall be treated as a right to receive a series of separate and distinct payments, and (iii) if the Executive is deemed on the date of termination to be a “specified employee” within the meaning of that term under Code Section 409A(a)(2)(B), then with regard to any payment or the provision of any benefit that is considered deferred compensation under Code Section 409A payable on account of a “separation from service,” such payment or benefit shall be made or provided at the date which is the earlier of (A) the expiration of the six (6)-month period measured from the date of such “separation from service” of Executive, and (B) the date of Executive’s death, to the extent required under Code Section 409A. Upon the expiration of the foregoing delay period, all payments and benefits delayed pursuant to this Section 7(j) (whether they would have otherwise been payable in a single sum or in installments in the absence of such delay) shall be paid in a lump sum, and any remaining payments and benefits due under this Agreement shall be paid or provided in accordance with the normal payment dates specified for them herein.

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(k) Survival. The provisions of Sections 1, 2 and 5 through 7 of this Agreement shall survive any termination of this Agreement in accordance with the terms of such sections.

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first above written.

THE COMPANY: ASPEN AEROGELS, INC.
By:	/s/ John F. Fairbanks
	Name: John F. Fairbanks
	Title:   Chief Financial Officer
THE EXECUTIVE:
/s/ Kevin Schmidt
Kevin Schmidt
21 Kimball Road Hopkinton, MA 01748 Telephone: (508) 625-1350

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EX-10.14

Exhibit 10.14

EXECUTIVE AGREEMENT

This Executive Agreement (this “Agreement”) is dated as of January 30, 2012, and is by and between Aspen Aerogels, Inc., a Delaware corporation (the “Company”) and Corby Whitaker (the “Executive”).

Recitals:

A. The Company desires to employ the Executive and the Executive desires to be so employed by the Company on the terms and conditions hereinafter set forth.

Agreement:

NOW, THEREFORE, the parties hereto agree as follows:

1. Definitions. As used herein, the following terms shall have the following meanings.

“Board” means the Company’s board of directors.

“Cause” means the Executive’s: (i) willful misconduct, dishonesty, fraud or breach of fiduciary duty to the Company; (ii) deliberate disregard of the lawful rules or policies of the Company; (iii) breach of this Agreement, a Related Agreement or any other agreement with the Company, which results in direct or indirect loss, damage or injury to the Company, monetarily or otherwise; (iv) unauthorized disclosure of any trade secret or confidential information of the Company; or (v) commission of an act which constitutes unfair competition with the Company or which induces any customer or supplier to breach a contract with the Company. For purposes hereof, whether or not the Executive has committed an act or omission of the type referred to in subparagraphs (i) through (v) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Company of the Executive’s employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Cause for purposes of this Agreement.

“Change of Control” means any of the following: (i) any Person or Group (within the meaning of Section 13(d)(3) of the Securities Exchange Act of 1934) (other than a Person or Group which was a shareholder of the Company on March 17, 2010) is or becomes the beneficial owner, directly or indirectly, through a purchase, merger or other acquisition transaction or series of transactions, of capital stock of the Company entitling such Person or Group to control 50% or more of the total voting power of the capital stock of the Company entitled to vote generally in the election of directors, where any voting capital stock of which such Person or Group is the beneficial owner that are not then outstanding are deemed outstanding for purposes of calculating such percentage; other than in connection with the Company’s issuance of its capital stock in a bona-fide financing transaction the proceeds of which are to be utilized by the Company for its general corporate purposes or (ii) any sale or transfer of all or substantially all of the assets of the Company to another Person.

“Good Reason” means the occurrence of any of the following conditions that are not cured by the Company within thirty (30) days after the Company’s receipt of written notice from the Executive specifying the conditions in reasonable detail (the “Notice”): (i) any material breach by the Company of this Agreement; (ii) the demotion of the Executive such that the Executive no longer serves in the position specified in Section 2(a)(i) below or a material reduction in the Executive’s current duties and authority in the position specified in Section 2(a)(i) below, in each case, without his consent; (iii) the written demand by the Company for the Executive to relocate or commute more than 40 miles from Northborough, Massachusetts without his consent; or (iv) a material reduction by the Company in the Executive’s Base Salary without his consent. The Notice must be given to the Company within ninety (90) days following the occurrence of the conditions constituting Good Reason. For purposes hereof, whether or not the Executive has Good Reason to terminate his employment by the Company pursuant to subparagraphs (i) through (iv) above will be determined by the Company in its reasonable, good faith discretion, based upon the facts known to the Company at the relevant time. Any termination by the Executive of his employment with the Company that does not meet the criteria set forth in this definition (determined as set forth in the immediately preceding sentence) shall be deemed to be without Good Reason for purposes of this Agreement.

“Permanent Disability” means the Executive is unable to perform, by reason of physical or mental incapacity, his then duties or obligations to the Company, for a total period of one hundred eighty (180) days in any three hundred sixty (360) day period.

“Person” means an individual, a partnership, a corporation, a limited liability company, an association, a joint stock company, a trust, a joint venture, an unincorporated organization or any other entity, including a governmental entity or any department, agency or political subdivision thereof.

“Related Agreement” means any confidentiality, non-competition, intellectual property assignment or similar agreement by and between the Executive and the Company, whether entered into on or prior to the date of the Agreement or entered into subsequent to the date of the Agreement.

2. Employment. The Company agrees to employ the Executive, and the Executive hereby accepts employment with the Company consistent with the Executive’s position and duties, upon the terms and conditions set forth in this Agreement for the period beginning on the date hereof and ending as provided in Section 2(c) (the “Employment Period”).

(a) Position and Duties.

(i) During the Employment Period, the Executive shall serve as Senior Vice President, Sales and Marketing of the Company and shall have the duties, responsibilities and authority consistent with such position that are designated by the Chief Executive Officer, subject to the direction and supervision of the Chief Executive Officer.

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(ii) The Executive shall devote his best efforts and his full business time and attention (except for permitted vacation periods and reasonable periods of illness or other incapacity) to the business and affairs of the Company. The Executive shall perform his duties and responsibilities to the best of his abilities in a diligent, trustworthy, businesslike and efficient manner. Notwithstanding the foregoing, the Executive may, to the extent not otherwise prohibited by this Agreement, devote such amount of time as does not interfere or compete with the performance of the Executive’s duties under this Agreement to any one or more of the following activities: (i) engaging in charitable activities, including serving on the boards of directors of charitable organizations or (ii) serving on the board of directors of any other company with the prior written approval of the Company.

(b) Salary and Benefits.

(i) During the Employment Period, the Executive’s base salary shall be $275,000 per year (such annual salary, as it may be adjusted upward by the Board or a committee thereof in its discretion, being referred to as the “Base Salary”). The Base Salary shall be payable in regular installments in accordance with the Company’s general payroll practices, shall be subject to customary withholding and may be increased (but not decreased) at the discretion of the Board or a committee thereof.

(ii) In addition to the Base Salary, Executive shall be eligible to receive an annual cash incentive bonus payment (each, a “Performance Bonus”) in an amount, if any, to be determined by the Company’s Board or a committee thereof. The Performance Bonus is deemed earned only if the Executive is employed on the last day of the year to which the Performance Bonus relates. The Performance Bonus will be paid in the year following the year to which the Performance Bonus relates.

(iii) The Company will reimburse the Executive for all reasonable travel and other expenses incurred by the Executive in connection with the performance of his duties and obligations under this Agreement. The Executive shall comply with such reasonable limitations and reporting requirements with respect to expenses as may be established by the Company from time to time.

(iv) In addition, the Executive will be entitled to participate in all compensation or employee benefit plans or programs and receive all benefits and perquisites for which salaried employees of the Company generally are eligible under any plan or program now or established later by the Company on the same basis as similarly situated senior executives of the Company. The Executive will participate to the extent permissible under the terms and provisions of such plans or programs, in accordance with program provisions. Nothing in this Agreement will preclude the Company from amending or terminating any of the plans or programs applicable to salaried employees or senior executives of the Company as long as such amendment or termination is applicable to all salaried employees or senior executives, as the case may be, so long as such plans or programs are replaced with plans no less favorable, in the aggregate, than existing plans.

(c) Employment at Will. The Executive and the Company understand and agree that the Executive is an employee at will, and that the Executive may resign, or the Company may terminate the Executive’s employment, at any time and for any or for no reason. Nothing in this Agreement shall be construed to alter the at-will nature of the Executive’s employment, nor shall anything in this Agreement be construed as providing the Executive with a definite term of employment or guaranteed nature or amount of compensation.

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(d) Severance. If the Executive’s employment with the Company is terminated (i) by the Company without Cause; or (ii) by the Executive for Good Reason within thirty (30) days after the occurrence of an event constituting Good Reason (including the expiration of any applicable cure periods), the Executive shall be entitled to (i) payment of the Executive’s Base Salary (prior to any reduction) for a period of three (3) months following the date of such termination; (ii) continued participation on substantially similar terms in all employee benefit plans and programs to which he was entitled to participate in as of the date of such termination for three (3) months following the date of such termination; and (iii) receive any accrued but unpaid bonuses or commissions fully earned by the Executive in accordance with Section 2(b)(ii) above (collectively, the “Severance Benefits”). The Executive hereby agrees that no severance compensation shall be payable upon termination of the Executive’s employment with the Company (i) by the Company with Cause; (ii) by the Executive without Good Reason; or (iii) as a result of the Executive’s death or Permanent Disability, and the Executive hereby waives any claim for severance compensation except as set forth in this Section 2(d). Executive’s entitlement to the Severance Benefits is subject to and conditioned upon his execution without revocation of the Release as set forth in Section 2(i) below.

(e) Termination or Reduction of Severance. If at any time after termination of employment hereunder the Executive breaches any of the provisions set forth in any Related Agreement, and if the Executive fails to cure each such breach, in all material respects, within thirty (30) days after the Company has given to the Executive written notice of such breach, the Executive shall no longer be entitled to any of the Severance Benefits pursuant to Section 2(d) above.

(f) Change of Control. In addition to the provisions of Section 2(d), if a Change of Control occurs and the Executive (i) does not receive an offer to remain employed by the Company for at least two years following the Change of Control in the position specified in Section 2(a)(i) above (or equivalent position) at a comparable rate of compensation, bonus, benefits and other material terms as set forth in this Agreement (including severance and termination provisions); and (ii) the Executive is terminated without Cause or resigns for any reason within the two year period following the Change of Control event, the Executive shall be entitled upon his termination of employment to receive the Severance Benefits. Executive’s entitlement to the Severance Benefits is subject to and conditioned upon his execution without revocation of the Release as set forth in Section 2(i) below.

(g) Options. The Executive will be granted an option to purchase shares of the Company’s common stock (the “Option”). The terms of the Option will be set forth in a stock option grant notice and incorporated stock option agreement (the “Grant”) and will be subject to the Company’s 2011 Employee, Director and Consultant Equity Incentive Plan (the “Plan”). Notwithstanding any terms in the Grant or the Plan to the contrary:

(i) upon (A) a Change of Control event, unless the Executive receives an offer to remain employed by the Company for at least two years following the Change of Control event in the position specified in Section 2(a)(i) above (or equivalent position) at a

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comparable rate of compensation, bonus, benefits and other material terms as contained in this Agreement; (B) the termination of the Executive’s employment with the Company without Cause or by the Executive for Good Reason at any time during the two (2) year period following the Change of Control event, the vesting of the Option will be accelerated such that the portion of the Option that would have vested (x) in the time period between the date of termination or Change of Control event, whichever is applicable, and the next anniversary of the Vesting Start Date (as such term is defined in the Grant) following the Change of Control event or date of termination, and (y) in the time period between such anniversary of the Vesting Start Date following the Change of Control event or date of termination and the immediately following anniversary of the Vesting Start Date, will be vested as of the Change in Control event or date of termination; and

(ii) if upon a merger, consolidation or sale of all or substantially all of the Company’s assets (a “Corporate Transaction”) the Option does not continue in the form of equity in the successor or acquiring entity such that vesting may continue to accrue after the Corporate Transaction then immediately prior to such Corporate Transaction the vesting of the Option will be accelerated such that the portion of the Option that would have vested (x) in the time period between the Corporate Transaction and the next anniversary of the Vesting Start Date following the Corporate Transaction, and (y) in the time period between such anniversary of the Vesting Start Date following the Corporate Transaction and the immediately following anniversary of the Vesting Start Date, will be vested.

(h) Parachute Payments. If Independent Tax Counsel (as that term is defined below) determines that the aggregate payments and benefits provided or to be provided to the Executive pursuant to this Agreement, and any other payments and benefits provided or to be provided to the Executive from the Company or any of its subsidiaries or other affiliates or any successors thereto constitute “parachute payments” as defined in Section 280G of the Internal Revenue Code of 1986, as amended (the “Code”) (or any successor provision thereto) (“Parachute Payments”) that would be subject to the excise tax imposed by Section 4999 of the Code (the “Excise Tax”), then, except as otherwise provided in the next sentence, such Parachute Payments shall be reduced to the extent the Independent Tax Counsel shall determine is necessary (but not below zero) so that no portion thereof shall be subject to the Excise Tax. If Independent Tax Counsel determines that the Executive would receive in the aggregate greater payments and benefits on an after tax basis if the Parachute Payments were not reduced pursuant to this Section 2(h), then no such reduction shall be made. The determination of which payments or benefits shall be reduced to avoid the Excise Tax shall be made by the Independent Tax Counsel, provided that the Independent Tax Counsel shall reduce or eliminate, as the case may be, payments or benefits in the order that it determines will produce the required deduction in total Parachute Payments with the least reduction in economic value to the Executive of such payments. The determination of the Independent Tax Counsel under this Section 2(h) shall be final and binding on all parties hereto. For purposes of this Section 2(h), “Independent Tax Counsel” shall mean a lawyer, a certified public accountant with a nationally recognized accounting firm, or a compensation consultant with a nationally recognized actuarial and benefits consulting firm with expertise in the area of executive compensation tax law, who shall be selected by the Board, and whose fees and disbursements shall be paid by the Company.

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(i) Severance and Release. The Executive’s right to receive the Severance Benefits shall be contingent upon the Executive’s execution and non-revocation (other than in the case of Executive’s death) within forty-five (45) days of his date of termination of a general release reasonably satisfactory to the Company releasing the Company, its officers, agents, stockholders, and affiliates from any liability for any matter other than for payments under this Agreement and contractual obligations under other written agreements which form shall be provided to the Executive on or prior to his date of termination (the “Release”). The Company hereby agrees that upon the lapse of the period for revocation set forth in the Release, if any, if the Executive has not exercised his revocation right, the Company will execute a counterpart of the Release and deliver it to Executive forthwith. The payment of the Severance Benefits shall commence in the sixty (60) day period following the Executive’s date of termination; provided that if a new calendar year commences during this period, the payments shall commence no earlier than January 1 of such new calendar year. The first payment after execution of the Release shall include all amounts that would have been paid following the date of termination had the Release been effective immediately following the date of termination but which were not yet paid.

3. Representations and Warranties of the Executive. Executive hereby represents and warrants to the Company that:

(a) The Executive:

(i) has not been convicted within the last five (5) years of any felony or misdemeanor in connection with the offer, purchase, or sale of any security or any felony involving fraud or deceit, including, but not limited to, forgery, embezzlement, obtaining money under false pretenses, larceny, or conspiracy to defraud;

(ii) is not currently subject to any state administrative enforcement order or judgment entered by a state securities administrator within the last five (5) years and is not subject to any state’s administrative enforcement order or judgment in which fraud or deceit (including, but not limited to, making untrue statements of material facts and omitting to state material facts) was found in which the order or judgment was entered within the last five (5) years; and

(b) This Agreement constitutes the legal, valid and binding obligations of the Executive, enforceable in accordance with its terms, and the execution, delivery and performance of this Agreement by the Executive does not and will not conflict with, violate or cause a breach of any agreement, contract or instrument to which the Executive is a party or any judgment, order or decree to which the Executive is subject.

4. Representations and Warranties of the Company. The Company hereby represents and warrants to the Executive that:

(a) The Company is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware. The Company has all requisite corporate power and authority to carry out the transactions contemplated by this Agreement.

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(b) The execution, delivery and performance of this Agreement has been duly authorized by the Company. This Agreement constitutes a valid and binding obligation of the Company, enforceable in accordance with its terms. The execution and delivery by the Company of this Agreement, and the fulfillment of and compliance with the respective terms hereof by the Company, do not and shall not (i) conflict with or result in a breach of the terms, conditions or provisions of, (ii) constitute a default under, (iii) result in the creation of any lien, security interest, charge or encumbrance upon the Company’s capital stock or assets pursuant to, (iv) give any third party the right to modify, terminate or accelerate any obligation under, (v) result in a violation of, or (vi) require any authorization, consent, approval, exemption or other action by or notice to any court or administrative or governmental body pursuant to, the charter or bylaws of the Company, or any law, statute, rule or regulation to which the Company is subject, or any agreement, instrument, order, judgment or decree to which the Company is subject.

5. Related Agreement. The Executive hereby reaffirms, confirms and approves each Related Agreement as a binding obligation of the Executive, enforceable in accordance with its terms. The Executive acknowledges and agrees that any Base Salary and/or Performance Bonus paid to the Executive pursuant to this Agreement shall serve as additional consideration for the Executive’s obligations under each Related Agreement.

6. Notices. All notices, demands or other communications to be given or delivered under or by reason of the provisions of this Agreement will be in writing and will be deemed to have been given when delivered personally, mailed by certified or registered mail, return receipt requested and postage prepaid, or sent via a nationally recognized overnight courier, or sent via facsimile to the recipient with a confirmation of receipt and accompanied by a certified or registered mailing. Such notices, demands and other communications will be sent to the address indicated below:

To the Company:

Aspen Aerogels, Inc.

30 Forbes Road

Northborough, MA 01532

Telephone: (508) 691-1111

Facsimile: (508) 691-1200

Attention: President and CEO

with copies (which shall not constitute notice) to:

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

One Financial Center

Boston, MA 02111

Telephone: (617) 542-6000

Facsimile: (617) 542-2241

Attention: Tom Burton

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To the Executive:

Address specified on signature page

or to such other address or to the attention of such other person as the recipient party has specified by prior written notice to the sending party.

7. Miscellaneous.

(a) Severability. Whenever possible, each provision of this Agreement will be interpreted in such manner as to be effective and valid under applicable law, but if any provision of this Agreement is held to be invalid, illegal or unenforceable in any respect under any applicable law or rule in any jurisdiction, such invalidity, illegality or unenforceability will not affect any other provision or any other jurisdiction, but this Agreement will be reformed, construed and enforced in such jurisdiction as if such invalid, illegal or unenforceable provision had never been contained herein.

(b) Complete Agreement. This Agreement and the agreements referred to herein (including, without limitation, each Related Agreement) embody the complete agreement and understanding among the parties and supersede and preempt any prior understandings, agreements or representations by or among the parties, written or oral, which may have related to the subject matter hereof.

(c) Waiver of Jury Trial. The parties to this Agreement each hereby waives, to the fullest extent permitted by law, any right to trial by jury of any claim, demand, action, or cause of action (i) arising under this Agreement or (ii) in any way connected with or related or incidental to the dealings of the parties hereto in respect of this Agreement or any of the transactions related hereto, in each case whether now existing or hereafter arising, and whether in contract, tort, equity, or otherwise. The parties to this Agreement each hereby agrees and consents that any such claim, demand, action, or cause of action shall be decided by court trial without a jury and that the parties to this Agreement may file an original counterpart or a copy of this Agreement with any court as written evidence of the consent of the parties hereto to the waiver of their right to trial by jury.

(d) Counterparts; Facsimile Transmission. This Agreement may be executed simultaneously in two or more counterparts, any one of which need not contain the signatures of more than one party, but all such counterparts taken together will constitute one and the same Agreement. This Agreement may also be executed and delivered by facsimile transmission.

(e) Successors and Assigns. The provisions hereof shall inure to the benefit of, and be binding upon and assignable to, successors of the Company by way of merger, consolidation or sale. The Executive may not assign or delegate to any third person the Executive’s obligations under this Agreement. The rights and benefits of the Executive under this Agreement are personal to him and no such right or benefit shall be subject to voluntary or involuntary alienation, assignment or transfer. The Company shall require any successor (whether direct or indirect, by purchase, merger, consolidation or otherwise) to all or substantially all of the business and/or assets of the Company expressly to assume and agree to

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perform this Agreement in the same manner and to the same extent that the Company would have been required to perform it if no such succession had taken place. As used in this Agreement, “the Company” shall mean both the Company as defined above and any such successor that assumes and agrees to perform this Agreement, by operation of law or otherwise.

(f) Governing Law. All issues concerning this Agreement shall be governed by and construed in accordance with the laws of the Commonwealth of Massachusetts, without giving effect to any choice of law or conflict of law provision or rule (whether of the Commonwealth of Massachusetts or any other jurisdiction) that would cause the application of the law of any jurisdiction other than the Commonwealth of Massachusetts.

(g) Remedies. The parties hereto agree and acknowledge that money damages may not be an adequate remedy for any breach of the provisions of this Agreement and that any party may in its sole discretion apply to any court of law or equity of competent jurisdiction (without posting any bond or deposit) for specific performance and/or injunctive or other relief in order to enforce or prevent any violations of the provisions of this Agreement.

(h) Amendment and Waiver. The provisions of this Agreement may be amended and waived only with the prior written consent of the Company and the Executive.

(i) Compliance with Code Section 409A. To the extent that any payment under this Agreement constitutes “nonqualified deferred compensation” for purposes of Section 409A of the Internal Revenue Code of 1986, as amended (the “Code”), (i) a termination of employment shall not be deemed to have occurred for purposes of any provision of this Agreement providing for the payment of any amounts or benefits upon or following a termination of employment unless such termination is also a “separation from service” within the meaning of Code Section 409A and, for purposes of any such provision of this Agreement, references to a “termination ,” “termination of employment” or like terms shall mean “separation from service,” (ii) the Executive’s right to receive any installment payments pursuant to this Agreement shall be treated as a right to receive a series of separate and distinct payments, and (iii) if the Executive is deemed on the date of termination to be a “specified employee” within the meaning of that term under Code Section 409A(a)(2)(B), then with regard to any payment or the provision of any benefit that is considered deferred compensation under Code Section 409A payable on account of a “separation from service,” such payment or benefit shall be made or provided at the date which is the earlier of (A) the expiration of the six (6)-month period measured from the date of such “separation from service” of Executive, and (B) the date of Executive’s death, to the extent required under Code Section 409A. Upon the expiration of the foregoing delay period, all payments and benefits delayed pursuant to this Section 7(i) (whether they would have otherwise been payable in a single sum or in installments in the absence of such delay) shall be paid in a lump sum, and any remaining payments and benefits due under this Agreement shall be paid or provided in accordance with the normal payment dates specified for them herein.

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(j) Survival. The provisions of Sections 1, 2 and 5 through 7 of this Agreement shall survive any termination of this Agreement in accordance with the terms of such sections.

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement as of the date first above written.

THE COMPANY:
ASPEN AEROGELS, INC.
By:	/s/ Donald R. Young
Name:	Donald R. Young
Title:	President & Chief Executive Officer

THE EXECUTIVE:

/s/ Corby Whitaker

Corby Whitaker

2451 Spyglass Drive

Oakland, MI 48363

Telephone: 713-409-0297

[Signature Page to Whitaker Executive Agreement]

EX-10.17

Exhibit 10.17

CROSS LICENSE AGREEMENT

THIS CROSS-LICENSE AGREEMENT (the “Agreement”) is made as of the 1st day of April, 2006 (the “Effective Date”) between:

Cabot Corporation, a corporation organized and existing under the laws of the State of Delaware whose principal place of business is at Two Seaport Lane, Boston, Massachusetts, 02210 (“Cabot”); and

Aspen Aerogels, Inc., a corporation organized and existing under the laws of the State of Delaware whose principal place of business is at 30 Forbes Road, Building B, Northborough, Massachusetts, 01532 (“Aspen”).

(Aspen and Cabot individually referred to herein as a “Party” and together as the “Parties”)

WHEREAS:

Aspen and Cabot each have patents and patent applications directed to various aspects of Aerogels, their methods or materials of manufacture and/or uses thereof;

Aspen and Cabot are interested in licensing certain of each other’s patents;

Aspen and Cabot are also interested in licensing each other’s patent applications and granted patents based thereon.

NOW, THEREFORE, in consideration of the mutual covenants herein contained and other good and valuable consideration, the receipt of which is hereby acknowledged, the Parties hereby agree as follows:

1. DEFINITIONS

1.1 “Aerogel(s)” shall mean a solid matrix gel with air or any other gas dispersed in it. This includes all forms of highly-divided states (small interconnected domains with high porosity, high surface area, and small pore size) of inorganic oxides, nonoxides, polymers, and carbons which can be achieved only by chemical preparation of the material and cannot be created by mechanical grinding or flame processing. This includes, by way of example, those solids which have been dried under supercritical conditions (above the critical temperature and pressure of the solvent) as originally conceived by S. S. Kistler in 1932 for which the name aerogel was given as well as solids which have been dried directly from a solvent but with minimal shrinkage.

1.2 “Aspen Blanket” shall mean a fiber reinforced Aerogel blanket or products derived therefrom.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

1.3 “Affiliates” shall mean, with respect to either Party, any entity which directly or indirectly controls, is controlled by, or under common control with, such Party. For the purposes of this definition, “controls” (including, with correlative meanings, “control,” “controlled by,” and “under common control with”) means the power to direct or cause the direction of the management and policies of such entity or party, as the case may be, directly or indirectly, whether through the ownership of voting securities, by contract, or otherwise. With respect to a corporation, limited liability company, partnership or other legal entity, “control” will also mean direct or indirect ownership of more than fifty percent (50%) of the voting stock, limited liability company interest, general partnership interest or voting interest in any such corporation, limited liability company, partnership or entity.

1.4 “Aspen Field of Use” shall mean

(1) the manufacture of the Aspen Blanket, using only [***] or oligomers of the foregoing, or any combinations thereof as primary feedstock, provided, however,

(a) that at least [***]% by weight of the Aerogel Structure of the Aspen Blanket shall be derived from these primary feedstock materials; and,

(b) the use of [***] shall be no more than [***]% by weight of the Aerogel Structure of the Aspen Blanket, and

(c) wherein the aforementioned manufacture shall have as its predominant means of drying (i.e. solvent removal), a step that uses a fluid which is at least [***]% (by volume) supercritical carbon dioxide, at a pressure of about [***] psi or greater, and

(2) the use and sale of the Aspen Blanket for energy dissipation, Separation, sound or thermal insulation applications.

1.5 “Cabot Field of Use” shall mean

(1) the manufacture of Aerogels, using only [***] or derivatives of the foregoing (other than [***]), or any combinations thereof as primary feedstock, provided, however, that at least [***]% of the Aerogel Structure of the Aerogels shall be derived from these primary feedstock materials and wherein the aforementioned manufacture shall have as its predominant means of drying (i.e. solvent removal), drying at a pressure that is less than about [***] psi, of Aerogels, and

(2) the use and sale of such Aerogels for energy dissipation, Separation, sound or thermal insulation applications.

1.6 “Change of Control” shall mean the happening of any of the following to occur:

(a) If, with respect to either Party, any person or entity or group of persons or entities acting in concert acquires ownership of or the right to vote or to direct the voting of shares of capital stock of such Party representing 50% or more of the total voting power of such Party; or

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(b) Either Party shall have merged into or consolidated with another entity, or merged another entity into the Party, on a basis whereby less than 50% of the total voting power of the surviving entity is represented by shares held by former shareholders of the Party prior to such merger or consolidation; or

(c) Either Party shall have sold substantially all of its Aerogel assets to another corporation, entity or person, excluding Affiliates, excluding a sale pursuant to a bankruptcy or insolvency proceeding.

Notwithstanding anything set forth in (a)-(c) above, a Change of Control shall not include a Qualified Public Offering (“QPO”) as such term is defined in the Amended and Restated Charter of Aspen as of the date of this Agreement.

1.7 “[***]” shall mean [***] of the following compounds: [***].

1.8 “Issued Patents” shall mean any and all patents worldwide that have issued as of the Effective Date and their corresponding counterpart applications pending elsewhere in the world and patents issued from such counterpart applications, which as of the Effective Date (a) are owned, controlled or licensed by a Party, and (b) a Party has the right to license without accounting to others, and (c) claim Aerogels, their methods or materials of manufacture and/or uses thereof.

1.9 “Aspen Issued Patents” shall mean those Issued Patents of Aspen and its Affiliates necessary for Cabot to practice within the Cabot Field of Use.

1.10 “Cabot Issued Patents” shall mean those Issued Patents of Cabot and its Affiliates necessary for Aspen to practice within the Aspen Field of Use. Without limiting the foregoing, Cabot Issued Patents shall specifically exclude all patents and/or patent applications licensed to Cabot from [***] (“[***]”) pursuant to the [***] Licensing and Joint Development Agreement by and between Cabot and [***] dated [***].

1.11 An “Event of Default” shall mean the happening of any of the following events:

(a) Aspen fails to pay Cabot when and as required to be paid herein any amount payable hereunder, including, but not limited to Aspen’s payment obligations in Sections 4.1(a) and 6.5 hereunder; or

(b) Either Party fails to perform or observe any other material covenant or agreement (not specified in subsection (a) above) contained in this Agreement to be performed or observed on its part or

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(c) Any material representation, warranty or certification made by or on behalf of either Party herein shall be incorrect, or misleading, in any material respect when made; or

(d) Cabot is unable to exchange its Equity Investment Credit at an Equity Closing, as contemplated in Section 4.1(b)(i) hereof provided an Equity Closing occurs prior to the expiration of 120 days following the execution of this Agreement; or

(e) If no Equity Closing occurs prior to the expiration of 120 days following the execution of this Agreement and Cabot is unable to exchange its Equity Investment Credit for Series D Preferred Stock of Aspen, as contemplated by Section 4.1(b)(iii), within 180 days following the execution of this Agreement; or

(f) Aspen fails to raise a total of at least $35,000,000 in debt and/or equity financings between the date of execution of this Agreement and September 30, 2007.

1.12 “Equity Closing” shall mean the closing and funding of the next round of equity financing in Aspen by investors contemplated in Section 4.1 (b) below, which shall include at least one Lead Investor, currently contemplated to occur within 120 days of the execution of this Agreement, in an amount of at least $35,000,000, excluding the Equity Investment Credit.

1.13 “Lead Investor” shall mean a new equity investor (other than Cabot) in Aspen who shall, at the Equity Closing, make the largest investment equal to or in excess of $10,000,000.

1.14 “[***]” shall mean the following compounds: [***].

1.15 “Patent Applications and Acquired Patents” shall mean, excluding those applications described in Section 1.8: (a) any (i) original or provisional applications; and (ii) continuations, continuations-in-part, divisionals, reissues or re-exams of Issued Patents that as of the Effective Date either Party or its Affiliates has the right to license without accounting to others, which are owned (by assignment or assignment obligation), controlled, acquired or licensed by a Party or its Affiliates, and which claim Aerogels, their methods or materials of manufacture and/or uses thereof and that are pending either as of the Effective Date or at any time during the Period, or claim priority to an application pending either as of the Effective Date or at any time during the Period, and issued patents based thereon; and (b) any and all worldwide issued patents licensed or acquired by a Party or its Affiliates, and which claim Aerogels, their methods or materials of manufacture and/or uses thereof that: (i) said Party or its Affiliates: has the right to license without accounting to others at any time during the Period, or (ii) claims priority to an owned, controlled, acquired or licensed application of a Party or its Affiliates pending either as of the Effective Date or at any time during the Period.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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For purposes of this definition and as used in Section 3.4 below, “Period” shall mean the term between the Effective Date and the five year anniversary of the Effective Date and “Shortened Period” shall mean the term between the Effective Date and the date of a Change of Control of a Party.

1.16 “Licensed Intellectual Property” shall mean (a) either Cabot Issued Patents or Aspen Issued Patents licensed hereunder, and (b) either Party’s Patent Applications and Acquired Patents licensed hereunder.

1.17 “Aerogel Structure” shall mean the mass of the primary 3-dimensional structure derived from the sol-gel step. This explicitly excludes the mass of any fiber, functionality enhancing additives and other treatments.

1.18 “Separation” shall mean the separation of one or more components from a mixture of components.

2. CROSS LICENSE OF ISSUED PATENTS

(a) Subject to the terms and conditions of this Agreement, Cabot hereby grants to Aspen as of the Effective Date, under Cabot Issued Patents, a non-exclusive, worldwide license, to make, have made, use and sell the Aspen Blanket solely in the Aspen Field of Use. This license shall include the right to grant sublicenses to (i) Aspen’s customers but only for their use of the Aspen Blanket in energy dissipation, Separation, sound or thermal insulation end-use applications and (ii) Aspen’s Affiliates (so long as such entity remains an Affiliate of Aspen). Such license will become effective as of the Effective Date and shall continue to be effective until the last to expire of the Cabot Issued Patents. This license may not be assigned or sublicensed to any third party without Cabot’s prior written consent except as expressly delineated herein.

(b) Subject to the terms and conditions of this Agreement, Aspen hereby grants to Cabot as of the Effective Date, under the Aspen Issued Patents, a non-exclusive, worldwide license, to make, have made, use and sell Aerogels, solely in the Cabot Field of Use. This license shall include the right to grant sublicenses to (i) Cabot’s customers but only for their use of the products in energy dissipation, Separation, sound or thermal insulation end-use applications and (ii) Cabot’s Affiliates (so long as such entity remains an Affiliate of Cabot). This license shall continue to be effective until the last to expire of the Aspen Issued Patents. This license may not be assigned or sublicensed to any third party without Aspen’s prior written consent except as expressly delineated herein.

(c) The above licenses shall be retroactive from the earlier of the date of grant or publication of the respective Party’s Issued Patents.

(d) Cabot agrees to maintain U.S. Patent [***] and its currently maintained foreign counterparts (“[***] Patents”) for their entire term, and Cabot represents and warrants that the [***] Patents are included within the Cabot Issued Patents.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(e) The Parties each agree not to sell, transfer, pledge or mortgage its respective Issued Patents or its Patent Applications and Acquired Patents except any Change of Control that includes a sale of either Party’s Aerogel business shall not be a prohibited sale for purposes of this paragraph.

(f) In the event of a Change of Control, the Parties agree that any intellectual property rights held by an acquiror prior to the Change of Control shall not be deemed Issued Patents hereunder.

Except as a joined party by [***], to the extent that Cabot has any right to enforce any patents and/or patent applications licensed to Cabot from [***] pursuant to the [***] Licensing and Joint Development Agreement by and between Cabot and [***] dated [***] (the “[***] Patents/Patent Applications”) or patents emanating from the [***] Patents/Patent Applications, Cabot agrees that it will not bring any infringement action against Aspen under, or attempt to enforce against Aspen, any such rights. Notwithstanding the foregoing, nothing herein shall be construed as limiting and/or affecting, in any way, [***]’s right to assert its patents or applications against Aspen.

3. CROSS LICENSE OF PATENT APPLICATIONS AND ACQUIRED PATENTS

3.1 Subject to the terms and conditions of this Agreement, Cabot agrees to grant to Aspen as of the Effective Date a non-exclusive, worldwide license to practice any invention claimed in its Patent Applications and Acquired Patents, only with respect to Aerogels and/or the Aspen Blanket manufactured using as its predominant means of drying (i.e. solvent removal), a step that uses a fluid which is at least [***]% (by volume) supercritical carbon dioxide, at a pressure of about [***] psi or greater. Such license shall be effective until the last to expire of the issued patents (as included in the definition in Section 1.15) and includes the right to sublicense only its customers to use products in any end-use applications. This license may be sublicensed to any Affiliate of Aspen, so long as such entity remains an Affiliate of Aspen. Notwithstanding the foregoing, (i) any claims to uses in the field of [***] in any of Cabot’s intellectual property described in Section 1.15 are not licensed by Cabot to Aspen under this Agreement; and (ii) Aspen may not use Cabot’s intellectual property described in Section 1.15 to manufacture or sell the Aerogels and/or the Aspen Blanket where the so manufactured or sold Aerogels and/or the Aspen Blanket is intended to be used in the field of [***]. The restrictions stated in (i) and (ii) of the preceding sentence shall run concurrent with the restrictions Cabot has or may have with [***] on licensing and/or selling into the field of [***] and shall cease when such restrictions cease. Cabot agrees to promptly notify Aspen following the time when such restrictions cease.

3.2 Subject to the terms and conditions of this Agreement, Aspen hereby grants to Cabot as of the Effective Date a non-exclusive, worldwide license to practice any invention claimed in its Patent Applications and Acquired Patents only with respect to Aerogels wherein the method of manufacture shall have as its predominant means of drying (i.e. solvent removal) drying at a pressure that is less than about [***] psi. This license shall

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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be effective until the last to expire of the issued patents (as included in the definition in Section 1.15) and includes the right to sublicense only its customers to use products in end-use applications. This license may be sublicensed to any Affiliate of Cabot, so long as such entity remains an Affiliate of Cabot.

3.3 Other than as expressly provided in this Agreement, nothing herein shall be deemed a grant or license, directly or indirectly, under any Issued Patents, Patent Applications and Acquired Patents, or any other intellectual property right (including, without limitation, know-how and trade secrets) of either party. More specifically, in the event claims of an Issued Patent dominate an invention claimed in a Patent Application and Acquired Patent in a particular jurisdiction, the practice of the invention in such Patent Application is restricted by a party’s Field of Use.

3.4 In the event of a Change of Control of a Party before the expiration of the Period (referred to in Section 1.15), the other Party shall have the sole option to change such Period to the Shortened Period.

3.5 The above licenses, once effective, shall be retroactive from the earlier of the date of grant or publication of the respective Patent Applications and Acquired Patents.

3.6 In the event of a Change of Control, the Parties agree that any intellectual property rights held by an acquiror prior to the Change of Control shall not be deemed Patent Applications and Acquired Patents hereunder.

4. FEES PAYABLE TO CABOT

4.1 In consideration of avoiding potential claims on prior use of the Cabot Issued Patents and avoiding legal fees associated therewith, and upon due execution and delivery of this Agreement by the Parties, Aspen agrees to pay Cabot a non-refundable fee of Twenty-four Million Dollars ($24,000,000) payable in two forms, cash and equity, as follows:

(a) Cash Payment

(i) Aspen shall pay Cabot a total of Eight Million Dollars ($8,000,000) cash in ten equal semi-annual installments of Eight-Hundred Thousand Dollars ($800,000) each commencing the sooner of September 1, 2006 or thirty (30) days after the Equity Closing.

(ii) All payments shall be made by wire transfer to such bank account as designated by Cabot in writing.

(iii) In the event of a Change of Control of Aspen, the unpaid balance of the Eight Million Dollar payment shall become immediately due and payable to Cabot within 30 days of such Change of Control.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(b) Equity Payment

(i) Aspen hereby grants Cabot a credit to be applied to an equity investment in Aspen of Sixteen Million Dollars ($16,000,000) (the “Equity Investment Credit”) for shares of convertible preferred stock of Aspen upon terms and conditions outlined below. The value of the Equity Investment Credit shall be $16,000,000 based on an expectation by the Parties that the total post money value of Aspen after the Equity Closing (including such Equity Investment Credit) (“Aspen’s Value”) will be not greater than $240 Million. In the event that Aspen’s Value is to exceed $240 Million at the Equity Closing, Cabot’s Equity Investment Credit shall be increased proportionately based on the increase in Aspen’s Value at such time.

(ii) In preparation of the Equity Closing, the Parties shall prepare and at the Equity Closing enter into a Share Purchase Agreement, a Stockholders’ Agreement and any other agreements necessary to enable Cabot to apply its Equity Investment Credit for convertible preferred shares (the “Equity Series”) in Aspen. The Parties have agreed that the stock provided at the Equity Closing will contain all the same legal and economic rights and privileges for Cabot as for the Lead Investor, except that in those certain cases set forth in Schedule B attached hereto where the Equity Series is entitled to vote on certain matters separately as a class, the requisite approval by the Equity Series will be determined without reference to the shares held by Cabot, and Cabot will then vote its shares of the Equity Series in the same proportion as the other holders of such Series. Without limiting the foregoing, Cabot shall have no vote for any representative on the board of directors of Aspen but will have the same registration rights granted to such Lead Investor, excluding the right to require an S-1 registration. In all other respects, Cabot shall have the same voting rights and privileges as all other holders of the Equity Series. The Share Purchase Agreement shall provide that Cabot shall have no access to information regarding Aspen, in its capacity as a shareholder of or investor in Aspen, other than the annual audited financial statements of Aspen commencing with those as of December 31, 2006 and the right to have informal discussions with the President of Aspen on a quarterly basis, during which no confidential or proprietary information of Aspen shall be discussed. Said annual audited financial statements shall be furnished to Cabot promptly upon becoming available, but in any event within 10 business days of the date they are issued by Aspen’s auditors. Finally, the Parties agree that the Share Purchase Agreement shall include an undertaking by Aspen to cause its legal counsel to deliver to Cabot at the Equity Closing a legal opinion in form and substance substantially identical to that opinion delivered to the other holders of the convertible preferred securities of Aspen with respect to all matters, including, but not limited to due incorporation, authorization and issuance of shares, approvals and the like.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(iii) In the event that the Equity Closing does not occur within 120 days of the date of the execution of this Agreement or, the Equity Closing does not provide Cabot the ability to apply its Equity Investment Credit as contemplated herein for whatever reason, Cabot may require Aspen to enter into all necessary agreements and obtain all necessary approvals required to apply Cabot’s Equity Investment Credit for shares of convertible preferred stock in Aspen upon the following terms:

(1) The investment shall be on terms no less favorable than those provided the Series D Preferred Shareholders, including their per share price, and shall provide Cabot rights and privileges equal to or superior to those already existing for the Series D Preferred Shareholders. The Parties shall enter into a Share Purchase Agreement and a Stockholder’s Agreement and any other agreement necessary to effectuate application of the Equity Investment Credit as provided for in this subsection. The Series D Preferred Stock issued to Cabot will contain all the same legal and economic rights and privileges for Cabot as for the lead investor in the original Series D round. Notwithstanding the foregoing, the same rights and exceptions outlined in Section 4.1(b)(ii) shall apply to the foregoing agreements, and Cabot shall be furnished with an opinion of counsel as described above.

(2) In addition, if, after the issuance of Series D Preferred Stock of Aspen to Cabot pursuant to this Section 4.1(b)(iii) but prior to a QPO, Aspen shall have an equity financing which meets the definition of “Equity Closing” at a valuation lower than the implied post money valuation of Aspen under its original Series D financing round ($150,000,000), the conversion price of the Series D Preferred Stock issued to Cabot under this Section 4.l(b)(iii) shall be reduced to give Cabot the same valuation as that received by the Lead Investor at said Equity Closing. In other words, Cabot shall have full ratchet anti dilution protection with respect to said equity financing round.

(3) The agreements identified in Section 4.1(b)(iii)(1) above shall provide for a closing to enable Cabot to apply its Equity Investment Credit as outlined above not later than six (6) months from the date of the execution of this Agreement and, in any event, prior to any QPO.

(iv) When Cabot acquires shares in Aspen in exchange for the Equity Investment Credit as outlined in paragraphs (ii) or (iii) above, Cabot agrees to provide Aspen with appropriate and customary representations and warranties, including:

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(1) That it would be acquiring such shares for investment for its own account, not as a nominee or agent, and not with the view to, or for resale in connection with, any distribution of any part thereof;

(2) That it understands that such shares to be acquired have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), or applicable state and other securities laws by reason of a specific exemption from the registrations provisions of the Securities Act and applicable state and other securities laws, the availability of which depends upon, among other things, the bona fide nature of the investment intent and the accuracy of Cabot’s representations as expressed therein.

(3) That it understands any transfer agent of Aspen shares will issue stop-transfer instructions with respect to such shares unless any transfer thereof is subsequently registered under the Securities Act and applicable state and other securities laws or unless an exemption from such registration is available.

5. REPRESENTATIONS, WARRANTIES AND DISCLAIMERS

5.1    (a) Cabot represents and warrants that it has the right to grant to Aspen the licenses set forth in this Agreement.

(b) Except as provided in sub-paragraph (a) of this Section and Section 2.1(d) above, Cabot makes no representation or gives any warranty with respect to the Licensed Intellectual Property licensed hereunder by Aspen. Cabot shall have no responsibility with respect to either (a) the use made of the Licensed Intellectual Property by Aspen or any third party or (b) any products made by Aspen or any third party under the Licensed Intellectual Property.

(c) Without limiting the generality of the foregoing, Cabot: (a) shall under no circumstances be liable for any loss, damage, personal injury or death resulting from, arising out of or connected with (i) the use by Aspen under this Agreement of the Licensed Intellectual Property made available hereunder or (ii) the use by Aspen or any third party of any products manufactured under the Licensed Intellectual Property.

5.2    (a) Aspen represents and warrants that it has the right to grant to Cabot the licenses set forth in this Agreement, including, but not limited to licenses under the following US patents and applications associated with the following publications (including their corresponding counterpart applications pending elsewhere in the world and/or all applications claiming priority to same): [***];[***] (limited to Aerogel related subject matter); [***] (limited to Aerogel related subject matter); [***] (limited to Aerogel related subject matter); [***]; [***]; [***]; and [***].

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(b) Except as provided in sub-paragraph (a) of this Section, Aspen makes no representation or gives any warranty with respect to the Licensed Intellectual Property licensed hereunder by Cabot. Aspen shall have no responsibility with respect to either (a) the use made of the Licensed Intellectual Property by Cabot or any third party or (b) any products made by Cabot or any third party under the Licensed Intellectual Property.

(c) Without limiting the generality of the foregoing, Aspen: (a) shall under no circumstances be liable for any loss, damage, personal injury or death resulting from, arising out of or connected with (i) the use by Cabot under this Agreement of the Licensed Intellectual Property made available hereunder or (ii) the use by Cabot or any third party of any products manufactured under the Licensed Intellectual Property.

5.3 Neither party gives any warranty regarding the validity of its Licensed Intellectual Property or that the utilization of its Licensed Intellectual Property will not result in the infringement of any third party’s patent, and grants no indemnity against any costs, damages, expenses or royalties resulting from any action taken by such third party. With respect to the Licensed Intellectual Property, neither party shall have any liability hereunder for any consequential, incidental, indirect, special or punitive damages.

5.4 EXCEPT AS SET FORTH IN THIS ARTICLE 5, THERE ARE NO WARRANTIES OR REPRESENTATIONS, EXPRESS OR IMPLIED, CONCERNING THE LICENSED INTELLECTUAL PROPERTY LICENSED HEREUNDER, AND NO SUCH WARRANTIES OR REPRESENTATIONS SHALL BE IMPLIED UNDER ANY APPLICABLE LAW OR IN EQUITY, INCLUDING WITHOUT LIMITATION, A WARRANTY OF MERCHANTABILITY AND A WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE OR ANY OTHER WARRANTY WHICH MAY BE IMPLIED UNDER COMMON LAW OR UNDER THE UNIFORM COMMERCIAL CODE OF ANY STATE OR OTHER JURISDICTION OF THE UNITED STATES OF AMERICA.

5.5 Aspen hereby represents and warrants that it has, or with respect to any preferred stock to be issued to Cabot pursuant to Section 4.1(b) will have on or prior to the closing date of the issuance of such preferred shares, the full right, power and authority, including any shareholder or Board of Director approvals which may be required under its Charter, Bylaws or otherwise to enter into this Agreement, and at the Closing, to transfer to Cabot the shares of Aspen contemplated in Section 4.1 (b).

5.6 Aspen hereby represents and warrants that it is not a party to, subject to or bound by any agreement or any judgment, order, writ, prohibition, injunction or decree of any court or other governmental body which would prevent the execution or delivery of this Agreement or the consummation of the transactions contemplated herein, provided, however, that the issuance of the preferred shares to Cabot as contemplated by Section 4.1(b) will be subject to obtaining the necessary consents from the Board of Directors and Stockholders and appropriate amendments to the Certificate of Incorporation of Aspen.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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5.7 Aspen hereby represents and warrants that it is a corporation duly organized, validly existing and in good standing under the laws of the State of Delaware, and has all requisite power and authority (corporate and otherwise) to own its properties, to carry on its business as now being conducted, to execute and deliver this Agreement and the agreements contemplated herein, and to consummate the transactions contemplated hereby and thereby. Aspen is duly qualified to do business and is in good standing in all jurisdictions in which its ownership of property or the character of its business requires such qualification. Aspen has furnished Cabot with copies of its most current Certificate of Incorporation, Bylaws and Shareholders Agreement currently in effect and such copies are true, correct and complete and contain all amendments as of the Effective Date.

5.8 Aspen hereby represents and warrants that as of the date of this Agreement the authorized capital stock of Aspen as of the Effective Date consists of 58,321,710 shares of Common Stock, having a par value of $0.01 and 24,688,009 shares of Preferred Stock, having a par value of $0.01. A summary capitalization table of Aspen is attached hereto as Schedule A, which table shows the number of shares of common stock, or common stock equivalents in the case of preferred stock, stock purchase warrants and stock options issued or issuable under Aspen’s equity and incentive plans as of the date of this Agreement.

5.9 Aspen hereby represents and warrants that: (a) the execution and delivery by Aspen of this Agreement and the agreements provided for herein, and the consummation by Aspen of all transactions contemplated hereunder and thereunder by Aspen, have been (or will be at the time such agreements may be entered into and/or such transactions consummated) duly authorized by all requisite corporate action, including, but not limited to any required shareholder approval. (b) This Agreement has been duly executed by Aspen. (c) This Agreement and all other agreements and obligations entered into and undertaken in connection with the transactions contemplated hereby to which Aspen is a party constitute the valid and legally binding obligations of Aspen, enforceable against it in accordance with its respective terms. (d) The execution, delivery and performance by Aspen of this Agreement and the agreements provided for herein, and the consummation by Aspen of the transactions contemplated hereby and thereby, will not, with or without the giving of notice or the passage of time or both, (i) violate the provisions of any law, rule or regulation applicable to Aspen; (ii) violate the provisions of the Certificate of Incorporation or Bylaws of Aspen; (iii) violate any judgment, decree, order or award of any court, governmental body or arbitrator; or (iv) conflict with or result in the breach or termination of any term or provision of, or constitute a default under, or cause any acceleration under, or cause the creation of any lien, charge or encumbrance upon the properties or assets of Aspen pursuant to, any indenture, mortgage, deed of trust or other instrument or agreement to which Aspen is a party or by which Aspen or any of its properties is or may be bound, provided, however, that the issuance of the preferred shares to Cabot as contemplated by Section 4.1(b) will be subject to obtaining the necessary consents from the Board of Directors and Stockholders and appropriate amendments to the Certificate of Incorporation of Aspen.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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5.10 Cabot hereby represents and warrants that: (a) the execution and delivery by Cabot of this Agreement and the agreements provided for herein, and the consummation by Cabot of all transactions contemplated hereunder and thereunder by Cabot, have been duly authorized by all requisite corporate action. (b) This Agreement has been duly executed by Cabot. (c) This Agreement and all other agreements and obligations entered into and undertaken in connection with the transactions contemplated hereby to which Cabot is a party constitute the valid and legally binding obligations of Cabot, enforceable against it in accordance with its respective terms. (d) The execution, delivery and performance by Cabot of this Agreement and the agreements provided for herein, and the consummation by Cabot of the transactions contemplated hereby and thereby, will not, with or without the giving of notice or the passage of time or both, (i) violate the provisions of any law, rule or regulation applicable to Cabot; (ii) violate the provisions of the Certificate of Incorporation or Bylaws of Cabot; or (iii) violate any judgment, decree, order or award of any court, governmental body or arbitrator.

5.11 Each Party respectively represents and warrants that as and from the Effective Date neither of them have sold, transferred, pledged or mortgaged its Issued Patents or its Patent Applications and Acquired Patents, respectively.

5.12 Without making any representations or warranties regarding the performance of any due diligence in this regard, Cabot represents to Aspen that as of the Effective Date, it has no actual knowledge that Aspen is infringing any patent of Cabot’s other than the [***] Patent.

6. MUTUAL AGREEMENTS AND COVENANTS

6.1 Both Parties hereby agree that neither Party is now, nor will be in the future, obliged by virtue of this Agreement or any agreements contemplated to be entered into in furtherance of this Agreement, to furnish any technical information or know-how to the other Party.

6.2 Both Parties hereby agree that they will act in good faith in carrying out the transactions contemplated in this Agreement and in particular, neither Party will use joint development of technology, transfer of Licensed Intellectual Property ownership or licenses with third parties to circumvent the intent of this Agreement with respect to the agreements contained herein concerning intellectual property.

6.3 The Parties agree that the right to bring suit against infringers or alleged infringers of the Licensed Intellectual Property shall reside at all times solely with (a) Cabot, with respect to Cabot Issued Patents and Cabot’s Patent Applications and Acquired Patents and (b) Aspen with respect to Aspen Issued Patents and Aspen’s Patent Applications and Acquired Patents. A party’s decision as to whether or not to bring suit against any infringer or alleged infringer of its Licensed Intellectual Property shall be accepted as final by the other Party.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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6.4 Nothing in this Agreement shall be construed as an admission by any party of infringement of any patent held by the other party.

6.5 Aspen hereby agrees to pay Cabot the same proportionate amount of any damages recovered or settlements it pays to any of the holders of the same class of convertible preferred securities of Aspen that Cabot acquires pursuant to either Sections 4.l(b)(i) or (iii) above (the “Other Holders”) within 5 days of any payment made to the Other Holders for the breach of any material representation, warranty or certification made by Aspen in the Share Purchase Agreement entered into by the Other Holders, or in any document delivered to the Other Holders in connection therewith.

6.6 Each Party agrees that it will not bring any legal challenge to the validity of any Licensed Intellectual Property so long as this Agreement shall not have been terminated in whole or in part.

7. TERM AND TERMINATION

7.1 This Agreement shall become effective on the Effective Date, and unless sooner terminated as provided herein below, shall continue until the expiration of the last to expire of the Issued Patents or Patent Applications and Acquired Patents licensed hereunder, at which time it shall expire. Any termination or expiration of this Agreement shall not affect any obligations on the part of Aspen to pay any of the consideration set forth in Article 4 to Cabot, except that such payment obligations shall terminate (a) where on account of an Event of Default by Cabot, Aspen either terminates the licenses it has granted hereunder to Cabot or terminates this Agreement in its entirety, or (b) if Cabot should terminate the Agreement on account of an Event of Default described in Section 1.11(f).

7.2 Upon the occurrence of an Event of Default by either Party (as defined in Section 1.11 above) the non-defaulting Party shall have the right to terminate this Agreement in whole or in part, as provided for in this Section, provided such Party has given the defaulting Party (a) written notice detailing the default (the “Default Notice”) and (b) a 30 day cure period to remedy the default (the “Cure Period”) which shall run as from the date of delivery of the Default Notice. Within 60 days of the expiration of the Cure Period the non-defaulting Party shall provide written notice to the defaulting Party of its election to terminate this Agreement in its entirety or to partially terminate the Agreement by terminating all of the licenses it has granted under this Agreement to the defaulting Party (“Partial Termination”). In the case of Partial Termination the non-defaulting party shall continue to hold the licenses granted by the defaulting Party under this Agreement and the defaulting Party shall continue to be obligated to comply with the provisions of this Cross License Agreement with respect thereto. Any termination of this Agreement pursuant to this Section shall be in addition to, and shall not be exclusive of or prejudicial to, any rights or remedies said non-defaulting party may have on account of any default hereunder, including, but not limited to the non-defaulting party’s right to proceed to protect its rights by suit in equity, action at law and/or other appropriate proceeding either for specific performance of any covenant or condition contained in this Agreement.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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Without limiting the foregoing, should Cabot terminate this Agreement on account of an Event of Default described in Sections 1.11(d) or (e), Cabot shall have the right, irrespective of whether any cash payments have been made to Cabot pursuant to Paragraph 4.1(a), to (a) revoke, effective as of the earlier of the date of grant or publication of its pertinent Issued Patents, any licenses granted herein and (b) commence against Aspen any suit, action or proceeding of any kind based upon assertion of infringement of any Issued Patent.

Notwithstanding the foregoing, should Cabot terminate this Agreement on account of an Event of Default described in Section 1.11(f), such termination must be a termination of this Agreement in its entirety, and Cabot shall return to Aspen, without consideration, any and all equity securities of Aspen it may have received from Aspen, and such securities shall be deemed cancelled as of the date of such termination.

8. CONFIDENTIALITY AND PUBLIC ANNOUNCEMENTS

8.1 Except as required by applicable laws, the Parties agree to maintain the economic terms of this Agreement in confidence and shall not disclose to any third party other than their respective board of directors, investors, bankers or other similar parties who have a need to know except with prior written approval of the other Party.

8.2 Neither Party shall issue any press release or make any such public statement relating to the subject matter of this Agreement prior to consultation with and securing written approval of the other Party. Upon request by any regulatory or administrative body or court of law for information relating to this Agreement, each Party agrees to notify the other of such request and upon providing any such information request confidential treatment of such information by the requesting regulatory or administrative body or court of law.

9. ASSIGNMENT

9.1 Neither this Agreement nor any interest herein may be assigned, in whole or in part, by either Party without the prior written consent of the other Party, which consent shall not be unreasonably withheld, except that either Party may assign its rights and obligations to (a) any Affiliate of an assigning Party, provided however, that such assignment shall not relieve the assigning Party of its performance obligations under this Agreement, or (b) to a successor entity in a Change of Control transaction, provided the successor entity agrees in writing to be bound by all of the terms of this Agreement. Notwithstanding the foregoing, no assignment may be made by any trustee or representative of either Party in any bankruptcy or insolvency proceeding without the prior written consent of the non-assigning Party. Any purported assignment in contravention of the above shall be void.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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10. APPLICABLE LAW AND DISPUTE RESOLUTION

10.1 This Agreement shall be construed and enforced in accordance with the laws of the Commonwealth of Massachusetts, without reference to its conflict of laws principles that might direct or refer determination of any such matter to the laws of any other jurisdiction.

10.2 The Parties shall endeavor to settle any dispute arising in connection with the interpretation, performance or termination of, or otherwise in connection with, or between the Parties to, this Agreement, through mutual consultation and negotiation. If no settlement can be reached through consultations of senior corporate management of the Parties within 30 days of one Party delivering a written notice of the dispute to the other Party, then such matter may be finally settled by any court of competent jurisdiction. Nothing herein shall amend either Party’s right to declare a termination in whole or in part of this Agreement as contemplated in Section 7.2 above.

11. NOTICE

11.1 It shall be sufficient giving of any notice, request or other communication in writing under this Agreement by a Party to this Agreement to the other Party if the Party desiring to give such notice, request or other communication in writing shall cause the notice to be personally delivered or sent by registered mail, telefax or recognized overnight delivery service properly addressed to the other Party at the address set forth below, or at such other address as the other party shall hereafter designate in writing. The date of giving of any such notice or other communication in writing shall be the date on which said copy was so delivered or sent properly addressed as aforesaid.

General Manager Aerogels	President
Cabot Corporation	Aspen Aerogels, Inc.
Two Seaport Lane	30 Forbes Road
Suite 1300	Building B
Boston, MA 02210	Northborough, MA 01532

12. FORCE MAJEURE

12.1 Neither Party shall be liable or penalized for its failure to perform any act or provide any right which it is obligated to perform or provide hereunder due to contingencies beyond its reasonable control (a “Force Majeure Event”), including but not limited to: acts of God, fires, floods, wars, sabotage, terrorism, accidents, epidemics, quarantine, labor disputes or shortages of manpower, governmental laws, judgments, ordinances, rules and regulations, whether valid or invalid, and inability to obtain material, power, equipment, or transportation, provided, however, that under no circumstances shall either Party be relieved of any payment obligations due hereunder because of a Force Majeure Event. The Party whose performance was prevented by any such contingency shall have the right to extend any time period during which it was obligated to perform hereunder for an additional period of time equal to the time its performance was prevented.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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13. NON WAIVER

13.1 The failure of a party hereto at any time to exercise any of its rights or options under this Agreement, except rights and options specifically limited as to a date or time of exercise thereof, shall not be construed to be a waiver of such rights or options, or prevent such party from subsequently asserting or exercising such rights or options.

14. SEVERABILITY

14.1 Should any of the terms of this Agreement be or become fully or partly invalid, the legal validity of the Agreement shall not be affected thereby. This applies also to any possible omission which may be found in the Agreement. In such cases, this Agreement shall be supplemented by a provision which, as far as is legally possible, comes nearest to what both parties hereto had desired or would have desired according to the sense and purpose of the Agreement, if they had considered the point when concluding the Agreement.

15. MERGER

15.1 This Agreement sets forth the entire agreement and understanding between the parties as to the subject matter hereof and merges all prior discussions, negotiations and agreements between them whether written or oral, and neither of the parties shall be bound by any decisions, agreements, covenants, definitions, warranties or representations with respect to the subject matter hereof, other than as expressly provided herein or as duly set forth on or subsequent to the date hereof in writing and signed by both parties.

(Remainder of Page Intentionally Left Blank)

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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IN WITNESS WHEREOF, the parties have executed this Agreement as of the day and year first above written.

CABOT CORPORATION		ASPEN AEROGELS, INC.
(Cabot)		(Aspen)
By:	/s/ Ravijit Paintal	By:	/s/ Carl J. Bilgrien
Name:	Ravijit Paintal	Name:	Carl J. Bilgrien
Title:	Vice President	Title:	Vice President
Date:	May 24, 2006	Date:	May 24, 2006

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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EXECUTION COPY

SETTLEMENT AGREEMENT AND

FIRST AMENDMENT TO CROSS LICENSE AGREEMENT

This Settlement Agreement and First Amendment to Cross License Agreement (hereinafter referred to as the “Settlement Agreement”) is made and entered into as of this 21st day of September, 2007, by and among Cabot Corporation, a Delaware corporation whose principal place of business is located at Two Seaport Lane, Boston, Massachusetts 02210 (“Cabot”), and Aspen Aerogels, Inc., a Delaware corporation whose principal place of business is located at 30 Forbes Road, Building B, Northborough, Massachusetts 01532 (“Aspen”).

WHEREAS, effective April 1, 2006, the Parties made and entered into a written Cross License Agreement (hereinafter referred to as the “CLA”), pursuant to which Cabot and Aspen resolved certain actual or potential disputes concerning their respective intellectual property rights involving the manufacture and use of Aerogels by agreeing to license to one another their related patents, pending and future patent applications, and patents granted thereon (collectively defined in Section 1.16 of the CLA, and hereinafter referred to in this Settlement Agreement, as the “Licensed Intellectual Property”), in consideration of the various payments and other consideration set forth in the CLA; and

WHEREAS, on or about December 20, 2006, Cabot delivered to Aspen a Notice of Default (hereinafter referred to as the “Notice of Default”) alleging, inter alia, that Aspen’s failure to make the Equity Payment to Cabot called for in Section 4.1(b) of the CLA constituted an Event of Default under the terms of the CLA (hereinafter referred to as the “Event of Default”), and that, if Aspen failed to cure the Event of Default within thirty (30) days of delivery of Cabot’s Notice of Default, Cabot reserved the right to terminate the CLA, in whole or in part, in accordance with its terms; and

WHEREAS, on or about February 23, 2007, Cabot delivered to Aspen a Notice of Partial

Termination of Cross License Agreement (hereinafter referred to as the “Notice of Partial Termination”) alleging, inter alia, that Cabot was terminating any and all licenses that Aspen had or may have had to the Cabot Issued Patents or the Cabot Patent Applications and Acquired Patents based upon Aspen’s failure to cure the Event of Default, in accordance with the terms of the CLA; and

WHEREAS, on or about January 17, 2007, Aspen commenced an action against Cabot in the Court of Chancery of the State of Delaware in and for New Castle County captioned Aspen Aerogels, Inc. v. Cabot Corporation, Civil Action No. 2675-N) (hereinafter referred to as the “Delaware Action”), asserting various claims concerning the CLA and the subject matter thereof; and

WHEREAS, on or about January 21, 2007, Aspen filed its First Amended Verified Complaint for Declaratory and Injunctive Relief in the Delaware Action asserting additional claims concerning the CLA and the subject matter thereof; and

WHEREAS, on or about March 26, 2007, Cabot filed its Answer to Aspen’s First Amended Verified Complaint and Counterclaims asserting various claims concerning the CLA and the subject matter thereof; and

WHEREAS, as reflected in the Delaware Action and otherwise, Cabot and Aspen have multiple actual or potential disagreements and disputes regarding, inter alia, their respective compliance with the terms of the CLA, the existence and legal effect of the Event of Default, the validity of the Notice of Default, the validity and enforceability of the Notice of Partial Termination, and the validity and enforceability of the Licensed Intellectual Property; and

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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WHEREAS, since the commencement of the Delaware Action, Cabot and Aspen have been engaged in discovery concerning their various claims, counterclaims and actual or potential defenses in that Action including, inter alia, their respective compliance with the terms of the CLA, the existence and legal effect of the Event of Default, the validity of the Notice of Default, the validity and enforceability of the Notice of Partial Termination, and the validity and enforceability of the Licensed Intellectual Property; and

WHEREAS Cabot and Aspen now desire to settle and resolve completely and forever any and all actual or threatened disagreements and disputes between themselves arising out of, related to, or connected in any way with the CLA, the Delaware Action, the Event of Default, the Notice of Default, the Notice of Partial Termination, or certain of the Licensed Intellectual Property;

NOW, THEREFORE, in exchange for the mutual promises and covenants contained herein and other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the Parties agree, as of the date set forth above, as follows:

I. AMENDMENTS TO THE CLA

The Notice of Default and the Notice of Partial Termination are hereby rescinded, ab initio, and shall be of no force or effect, and the CLA shall be in full force and effect, subject to the following amendments thereto:

A. Deletions

The following sections, subsections, terms and provisions of the CLA are hereby deleted in their entirety, and shall have no further force or effect:

(1) Section 1.11 (defining “Event of Default”);

(2) Section 1.12 (defining “Equity Closing”);

(3) Section 1.13 (defining “Lead Investor”);

(4) Section 4.1 (untitled);

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(5) Section 5.5 (untitled);

(6) The proviso only of Section 5.6;

(7) Section 5.8 (untitled);

(8) The proviso only of the last sentence of Section 5.9;

(9) Section 6.5 (untitled);

(10) Section 7.1 (untitled);

(11) Section 7.2 (untitled);

(12) Schedule A; and

(13) Schedule B.

B. Additions and Replacements

The following sections, subsections and provisions are hereby inserted and incorporated in the CLA in the locations noted, or amended as provided, and shall be immediately binding on the Parties:

(1) In Section 1.15, the second paragraph shall be amended to state:

“For purposes of this definition and as used in Section 3.4 below, ‘Period’ shall mean the term between the Effective Date and the earlier of (a) December 31, 2013, or (b) the date on which Aspen actually pays, in full, all fees and other amounts due or to become due to Cabot under Article 4 of this Agreement, infra, regardless of their due date(s), provided, however, that in no event shall the ‘Period’ be deemed to end prior to April 1, 2011; and ‘Shortened Period’ shall mean the term between the Effective Date and the date of a Change of Control of a Party.”

(2) In Article 4 titled “FEES PAYABLE TO CABOT,” the following sections shall be inserted:

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

4

“4.1 in consideration of, inter alia, the rescission of the Notice of Default and the Notice of Partial Termination, the avoidance of any actual or potential claims by Cabot arising from or related to Aspen’s use of the Cabot Issued Patents prior to the date of the Settlement Agreement and First Amendment to Cross License Agreement between the Parties (the “Settlement Agreement”), and the avoidance of further legal fees, expenses or financial exposure associated in any way with the Event of Default, the Notice of Default, the Notice of Partial Termination, the Licensed Intellectual Property or the Delaware Action, Aspen agrees to pay Cabot a non-refundable fee of Thirty-Eight Million Dollars ($38,000,000) in strict conformance with the following schedule:

Payment Due Date		Type A Payment		Type B Payment		Total Payment Due
	9/1/2006*	$	800,000		none	$	800,000
	/1/2007*	$	800,000		none	$	800,000
	9/1/2007*	$	800,000		none	$	800,000
	9/24/2007	$	500,000		none	$	500,000
	12/1/2007	$	500,000		none	$	500,000
	3/1/2008	$	1,300,000	$	100,000	$	1,400,000
	6/1/2008	$	500,000	$	100,000	$	600,000
	9/1/2008	$	1,300,000	$	100,000	$	1,400,000
	12/1/2008	$	500,000	$	100,000	$	600,000
	3/1/2009	$	1,300,000	$	200,000	$	1,500,000
	6/1/2009	$	500,000	$	200,000	$	700,000
	9/1/2009	$	1,300,000	$	200,000	$	1,500,000
	12/1/2009	$	500,000	$	200,000	$	700,000
	3/1/2010	$	1,425,000	$	825,000	$	2,250,000
	6/1/2010	$	625,000	$	825,000	$	1,450,000
	9/1/2010	$	1,425,000	$	825,000	$	2,250,000
	12/1/2010	$	625,000	$	825,000	$	1,450,000
	3/1/2011	$	1,425,000	$	875,000	$	2,300,000
	6/1/2011	$	625,000	$	875,000	$	1,500,000
	9/1/2011	$	625,000	$	875,000	$	1,500,000
	12/1/2011	$	625,000	$	875,000	$	1,500,000
	3/1/2012	$	750,000	$	750,000	$	1,500,000
	6/1/2012	$	750,000	$	750,000	$	1,500,000
	9/1/2012	$	750,000	$	750,000	$	1,500,000
	12/1/2012	$	750,000	$	750,000	$	1,500,000
	3/1/2013	$	750,000	$	750,000	$	1,500,000
	6/1/2013	$	750,000	$	750,000	$	1,500,000

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

5

Payment Due Date		Type A Payment		Type B Payment		Total Payment Due
	9/1/2013	$	750,000	$	750,000	$	1,500,000
	12/1/2013	$	750,000	$	750,000	$	1,500,000
	Totals	$	24,000,000	$	14,000,000	$	38,000,000

Aspen shall make each of the foregoing payments to Cabot in United States currency on or before the scheduled due date, provided, however, that Cabot acknowledges that the three (3) payments due on or before September 1, 2007 (in the total amount of $2,400,000) already have been timely paid in full by Aspen.”

“4.2 In the event of a Change of Control of Aspen, all remaining Type A Payments set forth in Section 4.1 shall become immediately due and payable in full to Cabot by Aspen irrespective of their originally scheduled due dates, and Aspen or its successor shall continue to make all remaining Type B Payments set forth in Section 4.1 in strict conformance with the schedule contained therein.”

“4.3 Notwithstanding any other provision of this Agreement, if Aspen fails to make a required payment to Cabot on or before its scheduled due date and such failure shall continue for a period of 30 days, or if on more than three (3) occasions Aspen fails to make a required payment to Cabot within three (3) business days of its scheduled due date, Cabot, in its sole discretion, may declare some or all remaining Type A Payments and Type B Payments set forth in Section 4.1 to be, whereupon the specific payments identified by Cabot in its declaration shall become, immediately due and payable in full to Cabot by Aspen irrespective of their originally scheduled due dates. In addition, any required payment not made within three (3) business days after it becomes due, whether as originally scheduled or as a result of acceleration, shall bear interest from the fourth (4th) business day after the date due until paid at the rate of 14% per annum (computed on the basis of a 360-day year consisting of twelve 30-day months),

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

6

compounding quarterly on the first day of each March, June, September and December. Without limiting Aspen’s other obligations under this Agreement, Aspen will also pay Cabot on demand such further amounts as shall be sufficient to cover all costs and expenses incurred by Cabot in any enforcement or collection of Aspen’s payment obligations under this Article 4, including, without limitation, reasonable attorneys’ fees, expenses and disbursements.”

“4.4 Aspen shall make all payments to Cabot under this Agreement by wire transfer to the following bank account, or by wire transfer to such other bank account as Cabot may designate from time-to-time in writing:

BANK NAME:	[***]
ADDRESS:	[***]
ABA NUMBER:	[***] (for domestic wires)
SWIFT CODE:	[***] (for foreign wires)
ACCT. NAME:	Cabot Corporation 2 Seaport Lane Boston, MA 02210
ACCT. NO.:	[***]”

(3) In Section 1.6 (defining the term “Change of Control”), the following clause shall be inserted at the end of subsection (a) following the word “Party”;

“, excluding any acquisition by one or more of the “Major Investors” (as such term is defined in the Settlement Agreement), or their Affiliates that have signed and delivered to Cabot Joinder Agreements, of 50% or more of the total voting power of Aspen.”

(4) Article 7 titled “TERM AND TERMINATION” is amended by inserting in place of the deleted Sections 7.1 and 7.2 the following:

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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“This Agreement shall become effective on the Effective Date and shall continue until the expiration of the last to expire of the Issued Patents or Patent Applications and Acquired Patents licensed hereunder, at which time it shall expire. If (a) Aspen shall fail to make any payment to Cabot when due in accordance with Section 4.1 and Aspen shall not make such payment (with interest if applicable under Section 4.3) within thirty (30) days after Cabot has given Aspen written notice of such failure, or (b) in accordance with Section 4.3 Cabot shall accelerate the due dates for any payments under Section 4.1 and Aspen shall thereafter fail to pay to Cabot within thirty (30) days after such acceleration all amounts then due to Cabot under Article 4 (i.e. the overdue payments giving rise to such acceleration, the payments accelerated, and any interest due thereon), then in either such case, Cabot may, at its option, at any time or times thereafter while any amounts then due under Article 4 remain unpaid, terminate all licenses to Aspen hereunder in their entirety, or may partially terminate the licenses to Aspen hereunder (a) by restricting the licenses to Aspen to specific Cabot Issued Patents, Patent Applications and Acquired Patents, or specific claims thereunder, (b) by reducing the Aspen Field of Use, and (c) in any other manner that narrows the scope of the licenses to Aspen. The notice of termination issued by Cabot shall either state that it is a termination of all licenses to Aspen hereunder, or shall specify the scope of the license remaining to Aspen hereunder. Any such termination by Cabot, whether of all licenses granted to Aspen or a partial termination as described above, shall not affect either the licenses granted by Aspen to Cabot hereunder, which shall continue in full force and effect for the remainder of the term of this Agreement, or Cabot’s right to receive payment in accordance with Article 4 of all amounts provided for therein. For the avoidance of doubt, if Cabot exercises its right to partially terminate the licenses granted to Aspen hereunder, Cabot shall continue to have the right at anytime thereafter while amounts then due to Cabot under Article 4 remain unpaid, by supplemental notice of termination to terminate all licenses granted to Aspen hereunder, or to further narrow the scope of the licenses remaining to Aspen hereunder.”

“Notwithstanding the foregoing if Cabot terminates the licenses to Aspen hereunder, in their entirety or partially, and if Aspen notifies Cabot within ten (10) days following any such termination that it is engaged in a process to sell Aspen or its assets, and if within ninety (90) days following any such termination such sale shall actually be completed and Cabot shall receive the full amount of all unpaid Type A and Type B payments (whether or not then due and payable) described in Section 4.1, and all interest accrued under Section 4.3, then any such default by Aspen shall be deemed cured, ab initio, and all licenses to Aspen hereunder shall be retroactively reinstated and shall remain in full force and effect for the remainder of the term of this Agreement.”

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(5) In each of Section 2(a)(i), Section 2(b)(i), in the second sentence of Section 3.1 and in the second sentence of Section 3.2, the following phrase shall be inserted after the word “customers”:

“and ultimate end users”

(6) Section 2(e) is amended in its entirety to read as follows:

“(e) Each of the Parties agrees not to sell, transfer, pledge or mortgage its respective Issued Patents or its Patent Applications and Acquired Patents except by an instrument that expressly recognizes that such sale, transfer, pledge or mortgage is subject to the licenses granted hereunder.”

(7) Section 10.2 is amended in its entirety to read as follows:

“10.2 Other than in a case involving a failure to make a payment under Article 4, the Parties shall endeavor to settle any dispute arising in connection with the interpretation or performance of, or otherwise in connection with this Agreement, through mutual consultation and negotiation. If no settlement can be reached through consultations of senior corporate management of the Parties within thirty (30) days of one Party delivering a written notice of dispute to the other Party, then such matter may be finally settled by a court of competent jurisdiction.”

C. No Other Changes

Other than as expressly amended or modified in this Section I, all of the provisions of the CLA shall remain in full force and effect, and are hereby ratified and affirmed by the Parties.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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II. SUBORDINATION OF PAYMENTS TO ASPEN’S INVESTORS

A. Definitions

As used in this Settlement Agreement, the following terms shall have the meanings set forth below:

(1) “Aspen Equity Investors” shall mean all persons who are now or hereafter become equity holders in Aspen, including without limitation the Major Investors, all Affiliates of such persons, and any person who executes a Joinder Agreement in accordance herewith. An Unaffiliated Institutional Lender shall not be deemed to be an Aspen Equity Investor on account of any Equity Kicker.

(2) “Joinder Agreement” shall mean an agreement in the form appended hereto as Exhibit A.

(3) “Unaffiliated Institutional Lender” shall mean Massachusetts Development Financing Authority, Heller Financial Leasing, Inc. and Atel Ventures, Inc. and any other institutional lender that is not a Major Investor or an Affiliate of a Major Investor.

(4) “Equity Kicker” shall mean any warrants or conversion rights given by Aspen as partial consideration for a loan from an Unaffiliated Institutional Lender, and any equity interests issued upon the exercise of such warrants or conversion rights.

(5) “Major Investors” shall mean Lehman Brothers Venture Capital Partners II, L.P., Lehman Brothers P.A. LLC, Lehman Brothers Partnership Account 2000/2001, L.P., Lehman Brothers Offshore Partnership Account 2000/2001, L.P., Lehman Brothers Venture Partners 2003-C, L.P., Lehman Brothers Venture Partners 2003-P, L.P., Lehman Brothers Venture Capital 2003 Partnership, Reservoir Capital Partners, L.P., Reservoir Capital Master Fund, L.P., RockPort Capital Partners, L.P., RP Co-Investment Fund I L.P., RockPort S II, LLC and RockPort Capital Partners II, L.P.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(6) “Cabot Senior Obligations” shall mean the Type A Payments required to be paid to Cabot pursuant to the CLA, as amended, including, without limitation, Type A Payments not yet due and payable, and the Type B Payments required to be paid to Cabot pursuant to the CLA, as amended, that are due and payable.

(7) “Junior Interests” shall mean all current or future debt or equity of Aspen held by an Aspen Equity Investor, and all Equity Kickers whether or not held by an Aspen Equity Investor; provided that rights to the following amounts in respect of 14% Senior Secured Notes shall not be considered Junior Interests, whether or not held by an Aspen Equity Investor: (a) principal (including capitalized interest) outstanding as of August 1, 2007, (b) increases in principal resulting from the capitalization of interest accrued after August 1, 2007 at the rate of l4% per annum or lower, or (c) interest accrued at the rate of 14% per annum or lower on the principal permitted by the foregoing clauses (a) and (b).

(8) “Junior Payments” shall mean all payments on account of any Junior Interest, whether principal, interest, dividends, redemption payments or otherwise, and whether paid in cash or other property, except for a payment consisting solely of a Junior Interest; provided, however, that the following payments on account of 14% Senior Secured Notes shall not be considered Junior Payments: (a) any payment of principal (including capitalized interest) outstanding as of August 1, 2007, or increases in principal thereafter resulting from the capitalization of interest accrued at the rate of 14% per annum or lower, or (b) any payment of interest accrued at the rate of 14% per annum or lower on the principal permitted by the foregoing clause (a).”

(9) “14% Senior Secured Notes” shall mean the 14% Senior Secured Notes issued by Aspen due 2010 outstanding to the parties and in the amounts set forth on Schedule I hereto, which shows the original principal amounts of such notes, the capitalized interest, and the accrued interest thereunder as of August 1, 2007.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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B. Subordination of Junior Interests

(1) Until all Cabot Senior Obligations have been paid, Aspen shall not make any Junior Payments, and no holder of Junior Interests shall accept or retain any Junior Payment, provided, however, that nothing herein shall prevent any holder of Junior Interests from converting such Junior Interests into, or exchanging such Junior Interests for, other Junior Interests; and provided, further that Aspen may pay up to a maximum of $5,000,000 to the holders of outstanding Bridge Notes who are listed in Schedule II attached hereto and who are not Major Investors if such payment is made out of new funds (i.e., cash, not conversion of bridge loans or other debt) paid into Aspen, not more than 30 days prior to the repayment of such Bridge Notes, for Junior Interests issued to Aspen Equity Investors who have executed and delivered to Cabot Joinder Agreements.

(2) In the event of any insolvency, bankruptcy, receivership, liquidation, reorganization or other similar proceedings, relative Aspen or to its property, or in the event of any proceedings for voluntary liquidation, dissolution or other winding up of Aspen, whether or not involving insolvency or bankruptcy, Cabot shall be entitled in any such proceedings to receive payment in full of all Cabot Senior Obligations before the holders of Junior Interests are entitled in such proceedings to receive any Junior Payment, and to that end any Junior Payment to which the holders of Junior Interests would be entitled but for the provisions hereof shall be delivered to Cabot to the extent necessary to make payment in full of all Cabot Senior Obligations, after giving effect to any concurrent payment or distribution to Cabot in respect thereof; provided, however, that the holders of the Junior Interests shall be entitled to receive and

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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retain Junior Payments consisting of reorganization securities, including, without limitation, any equity or debt security issued by Aspen or its bankruptcy or receivership estate in or in connection with any insolvency proceeding, but all such reorganization securities received as a Junior Payment shall be deemed Junior Interests for the purposes hereof.

(3) If, notwithstanding its agreement hereunder, Aspen makes any Junior Payment, except as permitted in Paragraph II(B)(1), above, before all of the Cabot Senior Obligations have been paid in full, such payment shall be held in trust for the benefit of, and shall be paid over to Cabot promptly on demand for application to the payment of all Cabot Senior Obligations until the same shall have been paid in full, after giving effect to any concurrent payment or distribution to the holders of such Cabot Senior Obligations.

(4) No Aspen Equity Investor that has signed a Joinder Agreement shall sell, assign or otherwise transfer, in whole or in part, any Junior Interests or any interest therein, to any other person or entity (a “Transferee”) unless and until such Transferee signs and delivers to Aspen and to Cabot a Joinder Agreement.

C. Aspen’s Obligation to Assure Investor Agreement and Compliance

(1) Aspen represents that Schedule II attached hereto includes an accurate list, as of the date of this Settlement Agreement, showing the identity of each Aspen Equity Investor holding Junior Interests consisting of debt and the principal amount of each type of debt held by such Aspen Equity Investor.

(2) Contemporaneous with the execution of this Settlement Agreement, Aspen shall deliver to Cabot one or more Joinder Agreements executed by each Major Investor and by each Affiliate of a Major Investor holding Junior Interests consisting of debt or holding 14% Senior Secured Notes.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(3) Aspen shall not issue any additional Junior Interests after the date of this Settlement Agreement unless and until either (i) the terms of such Junior Interests expressly incorporate the provisions or this Article II for the benefit of Cabot, or (ii) prior to or contemporaneous therewith, the party to whom such Junior Interests are to be issued executes and delivers to Cabot a Joinder Agreement.

(4) If any Aspen Equity Investor who does not execute a Joinder Agreement has, as of the date of this Settlement Agreement, a contractual right to receive now or in the future a Junior Payment, nothing herein shall be construed as requiring Aspen to breach its contractual obligation to such Aspen Equity Investor, provided, however, that in such case, unless such Junior Payment is permitted under Paragraph II(B)(1), above, Aspen shall pay all Cabot Senior Obligations prior to, or concurrent with, making the contractually required Junior Payment.

III. RELEASES AND COVENANTS

A. By Aspen

(1) Contemporaneous with the execution of this Settlement Agreement, Aspen, by its authorized representative, shall execute and deliver to Cabot a Release in the form attached hereto as Exhibit B.

(2) Aspen covenants and agrees not to challenge or cause to be challenged, directly or indirectly, the validity or enforceability of (a) any of the Cabot Issued Patents, (b) any patent that actually is issued to or acquired by Cabot on or before July 1, 2007 on account of one or more of the licensed Patent Applications and Acquired Patents, or (c) any foreign counterparts of the patents in (b) regardless of when they are issued, in any court or tribunal, before any administrative body (including, without limitation, the United States Patent and Trademark

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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Office), or in any other public or private forum or proceeding. Aspen hereby waives any and all such invalidity and unenforceability claims and defenses in any future litigation, arbitration or other public or private proceeding. This covenant and waiver shall survive the termination of this Settlement Agreement and permanently shall bind Aspen, its successors, assignees, and those who act for or in concert with any of them (including, without limitation, any assignee of any of the Aspen Issued Patents).

B. By Cabot

(1) Contemporaneous with the execution of this Settlement Agreement, Cabot, by its authorized representative, shall execute and deliver to Aspen a Release in the form attached hereto as Exhibit C.

(2) Cabot covenants and agrees not to challenge or cause to be challenged, directly or indirectly, the validity or enforceability of (a) any of the Aspen Issued Patents, (b) any patent that actually is issued to or acquired by Aspen on or before July 1, 2007 on account of one or more of the licensed Patent Applications and Acquired Patents, or (c) any foreign counterparts of the patents in (b) regardless of when they are issued, in any court or tribunal, before any administrative body (including, without limitation, the United States Patent and Trademark Office), or in any other public or private forum or proceeding. Cabot hereby waives any and all such invalidity and unenforceability claims and defenses in any future litigation, arbitration or other public or private proceeding. This covenant and waiver shall survive the termination of this Settlement Agreement and permanently shall bind Cabot, its successors, assignees, and those who act for or in concert with any of them (including, without limitation, any assignee of any of the Cabot Issued Patents).

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(3) Cabot irrevocably and permanently waives for itself and its successors and assigns any right it had or may have at any time in the future (to the extent any) to, directly or indirectly, assert that the 14% Senior Secured Notes (and the payments related thereto that are not considered Junior Payments as provided in Article III.A((8) of the CLA, as amended above) are subject to re-characterization, subordination (whether equitable, contractual or otherwise) or any other challenge by Cabot or any person or entity under any applicable law, including, without limitation, Title 11 of the United States Code.

IV. DISMISSAL OF THE DELAWARE ACTION; RETURN OF SERIES D TENDER

A. Contemporaneous with the execution of this Settlement Agreement, including all exhibits and schedules hereto, counsel of record for Cabot and Aspen in the Delaware Action shall sign and file a Stipulation of Dismissal of the Delaware Action in the form attached hereto as Exhibit D.

B. Each of the Parties understands and agrees that it alone shall bear the costs, expenses, and attorney’s fees that it has incurred arising from or related to the Delaware Action.

C. Contemporaneous with the execution of this Settlement Agreement, Cabot shall return to Aspen all of the original copies of the documents comprising the Series D Preferred Stock tender made by Aspen on January 19, 2007, including without limitation, the stock certificate evidencing 5,429,066 shares of Series D Preferred Stock.

D. Cabot shall, within five (5) business days following the execution of this Settlement Agreement, return to Aspen or destroy (i) all materials relating to Aspen and its business delivered to Cabot or its representatives in November and December 2006 and January 2007 in connection with negotiations over the exercise of Cabot’s “Equity Investment Credit” (as

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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such term was defined in the CLA) that Cabot and its representatives identify based on a reasonable search of their files; provided, however, that neither Cabot nor its representatives shall be required to search their e-mail files, deleted e-mail files or back-up e-mail files for such materials, and (ii) all discovery materials (e.g., documents, papers, and records, whether in paper or electronic format) furnished to it by Aspen in connection with the Delaware Action, including without limitation all computer readable discs received from Kroll, and all copies thereof made by Cabot or its representatives. Promptly thereafter Cabot shall certify in writing that all such records have been returned to Aspen or destroyed in compliance with this paragraph. If, after such five (5) day period, Cabot or its representatives should come upon any of the materials described in this paragraph in hard copy or electronic format of any kind, such materials will be kept confidential and will be promptly destroyed.

E. Aspen shall, within five (5) business days following the execution of this Settlement Agreement, return to Cabot or destroy all discovery materials (e.g., documents, papers, and records, whether in paper or electronic format) furnished to it by Cabot in connection with the Delaware Action, and any copies thereof made by Aspen, its representatives or Affiliates. Promptly thereafter Aspen shall certify in writing that all such records have been returned to Cabot or destroyed in compliance with this paragraph. If, after such 5 day period, Aspen or its representatives should come upon any of the materials described in this paragraph in hard copy or electronic format of any kind, such materials will be kept confidential and will be promptly destroyed.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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V. REPRESENTATIONS AND WARRANTIES

A. By Aspen

(1) Aspen represents and warrants that it is not a party to, subject to or bound by any agreement or any judgment, order, writ, prohibition, injunction or decree of any court or other governmental body which would prevent the execution or delivery of this Settlement Agreement or the performance of its obligations hereunder.

(2) Aspen represents and warrants that this Settlement Agreement, including all exhibits and schedules hereto, and the CLA, as amended, constitute valid and legally binding obligations of Aspen, enforceable against it in accordance with their respective terms.

(3) Aspen represents and warrants that Schedule III is a complete and accurate summary of all equity interests issued by Aspen on or before the date of this Agreement, showing for each class of interests (a) a description of the interest, (b) the total number issued, and (c) the aggregate cash consideration received by Aspen therefor. Since its incorporation, Aspen has not redeemed any of its equity interests.

(4) Aspen represents and warrants that Schedules I and II are a complete and accurate summary as of the date hereof of all indebtedness of Aspen for money borrowed, or evidenced by a promissory note, showing for each type of indebtedness (a) the total principal and due date, (b) the interest rate or rates, (c) the principal amount held by Major Investors or their Affiliates, and (d) the principal amount held by other Aspen Equity Investors.

B. By Cabot

(1) Cabot represents and warrants that it is not a party to, subject to or bound by any agreement or any judgment, order, writ, prohibition, injunction or decree of any court, or other governmental body which would prevent the execution or delivery of this Settlement Agreement or the performance of its obligations hereunder.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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(2) Cabot represents and warrants that this Settlement Agreement, including all exhibits and schedules hereto, and the CLA, as amended, constitute valid and legally binding obligations of Cabot, enforceable against it in accordance with their respective terms.

C. By Both Parties

(1) Both Parties agree that they will act in good faith in carrying out the obligations and transactions contemplated in this Settlement Agreement.

(2) Both Parties agree that nothing in this Settlement Agreement is intended to be, or shall be construed as, an admission of any breach, liability or wrongdoing by any Party.

D. Remedy for Certain Misrepresentations

Aspen recognizes and acknowledges that Cabot is relying on the representations and warranties contained in Paragraphs V(A)(3) and V(A)(4), above, in entering into this Settlement Agreement; and Aspen agrees that if such any representations and warranties shall prove to have been materially false when made, without limiting any other legal or equitable remedies that Cabot may have, Cabot shall have the right to terminate, in whole or in part, the licenses granted by it to Aspen under the CLA, in the manner described in Article 7 of the CLA, as amended.

VI. MISCELLANEOUS TERMS

A. This Settlement Agreement shall be construed and enforced in accordance with the laws of the Commonwealth of Massachusetts, without reference to its conflict of laws principles that might direct or refer determination of any such matter to the laws of any other jurisdiction.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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B. All disputes arising out of the interpretation, performance or termination of, or otherwise in connection with, this Settlement Agreement shall be submitted exclusively to the Court of Chancery of the State of Delaware in and for New Castle County for resolution.

C. The failure of a party hereto at any time to exercise any of its rights or options under this Settlement Agreement shall not be construed to be a waiver of such rights or options, or prevent such party from subsequently asserting or exercising such rights or options.

D. Should any of the terms of this Settlement Agreement be or become fully or partly invalid, the legal validity of the Settlement Agreement shall not be affected thereby. In such cases, this Settlement Agreement shall be supplemented by a provision which, as far as is legally possible, comes nearest to what both parties hereto had desired or would have desired according to the sense and purpose of the Settlement Agreement, if they had considered the point when concluding the Settlement Agreement.

E. This Settlement Agreement and the CLA, as amended hereby, are intended by the Parties to be the final expression of their agreement and a complete and exclusive statement of all of its terms. Taken together, this Settlement Agreement and the CLA, including any and all recitals therein and exhibits thereto, constitute the entire and only agreement and understanding between the Parties, and supersede any and all prior discussions, negotiations and agreements, whether oral or in writing, between the Parties. The terms of this Settlement Agreement shall not be modified or amended in any way except as set forth in a written agreement signed by corporate officers of both Parties.

F. Capitalized terms used in this Settlement Agreement which are defined in the CLA and are not otherwise defined herein shall have the meanings attributed to them in the CLA.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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G. This Settlement Agreement may be executed in any number of counterparts, each of which shall he deemed to be an original but all of which together shall constitute one and the same instrument.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

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WHEREFORE, Aspen and Cabot state that they have read this Settlement Agreement, including all exhibits and schedules hereto, have consulted with their counsel regarding their contents, and fully understand and accept the terms thereof in their entirety and without reservation as of the date first above written.

CABOT CORPORATION		ASPEN AEROGELS, INC.
By:	/s/ Ravijit Paintal	By:	/s/ Donald R. Young
	Ravijit Paintal
Title:	Vice President	Title:	President & CEO

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

22

Exhibit A

ASPEN AEROGELS, INC.

JOINDER AGREEMENT

Each of the undersigned has received copies of the Cross License Agreement, dated as of April 1, 2006, between Cabot Corporation (“Cabot’) and Aspen Aerogels, Inc. (“Aspen”) (the “CLA”), and the Settlement Agreement and First Amendment to Cross License Agreement, dated as of September 21, 2007, between Cabot and Aspen (the “Settlement Agreement”).

Each of the undersigned hereby agrees to be bound by terms of Section II (entitled “Subordination of Payments to Aspen’s Investors”) of the Settlement Agreement with all of the obligations specified therein.

Each of the undersigned further agrees that this Joinder Agreement shall be effective and irrevocable upon the delivery to Cabot of a copy (whether original, facsimile, electronic or other) of this Joinder Agreement, signed by a representative of the undersigned, without any notice of acceptance thereof by or from Cabot.

Executed as a sealed instrument under Massachusetts law as of the             day of             , 20    .

YOU MAY USE ONE JOINDER AGREEMENT FOR EACH MAJOR INVESTOR AND ITS AFFILIATES
	Typed or Printed Name(s)
	By:
	Name:
	Title:

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

23

EXHIBIT B

RELEASE

In consideration of payment of the sum of One Dollar ($1.00), together with other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, Aspen Aerogels, Inc., on behalf of itself and each of its subsidiaries, divisions, affiliates, corporate parents, joint ventures, partnerships, limited partnerships, predecessors, successors and assigns and each director, officer, general partner, limited partner, employee, servant and agent thereof (hereinafter collectively referred to as the “RELEASORS”), hereby remise, release and forever discharge Cabot Corporation and each of its subsidiaries, divisions, affiliates, joint ventures, partnerships, limited partnerships, and each director, officer, general partner, limited partner, stockholder, holder of indebtedness, employee, servant, agent and attorney thereof (hereinafter collectively referred to as the “RELEASEES”), of and from all debts, demands, causes of action, suits, accounts, covenants, contracts, agreements, damages, and any and all claims, defenses, demands, and liabilities whatsoever of every name, and, nature both in law or in equity, which the RELEASORS now have or ever had against the RELEASEES, from the beginning of time to the date of this Release, arising out of, related to, or connected with the Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of April 1, 2006 (hereinafter referred to as the “CLA”), or the Event of Default, Notice of Default, Notice of Partial Termination or Licensed Intellectual Property as they are defined in the Settlement Agreement and First Amendment to Cross License Agreement between Aspen Aerogels, Inc, and Cabot Corporation, dated as of September 21, 2007 (hereinafter referred to as the “Settlement Agreement”), including, without limitation, all claims, counterclaims and defenses asserted, or that could have been asserted, by the RELEASORS in, or in connection with, the litigation

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 1 of 3

captioned Aspen Aerogels, Inc. v. Cabot Corporation, Civil Action No 2675-N, pending in the Court of Chancery of the State of Delaware in and for New Castle County, and all claims, counterclaims and defenses asserted, that could have been asserted, or that could be asserted in the future by the RELEASORS arising out of, related to, or connected with the validity or enforceability of (a) any of the Cabot Issued Patents, (b) any patent that actually is issued to or acquired by Cabot on or before July 1, 2007 on account of one or more of the licensed Patent Applications and Acquired Patents, or (c) any foreign counterparts of the patents referenced in (b), supra, regardless of when they are issued.

By executing this Release, the RELEASORS agree and acknowledge that their representatives have read this document with care and with the advice of counsel, and that no representation of fact or opinion has been made to the RELEASORS by anyone which has induced the RELEASORS in any manner to execute this Release.

Capitalized terms used in this Release but not otherwise defined shall have the meanings attributed to them in the CLA and/or the Settlement Agreement.

Nothing herein is intended to, or shall be construed to, release or discharge any obligations for future performance, or restrictions imposed upon any rights granted, under the CLA, as amended, or the Settlement Agreement.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 2 of 3

In WITNESS HEREOF, the RELEASERS have caused this release to be executed by their duly authorized representatives this             day of September, 2007.

ASPEN AEROGELS, INC.
By:
	Name:
	Title:
WITNESS
Name:
Title:

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 3 of 3

Exhibit C

RELEASE

For good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, Cabot Corporation, on behalf of itself and each of its subsidiaries, divisions, affiliates, corporate parents, joint ventures, partnerships, limited partnerships, predecessors, successors and assigns and each director, officer, general partner, limited partner, employee, servant and agent thereof (hereinafter collectively referred to as the “RELEASORS”), hereby remise, release and forever discharge Aspen Aerogels, Inc., and each of its subsidiaries, divisions, affiliates, joint ventures, partnerships, limited partnerships, and each director, officer, general partner, limited partner, stockholder, holder of indebtedness, employee, servant, agent and attorney thereof (hereinafter collectively, referred to as the “RELEASEES”), of and from all debts, demands, actions, causes of action, suits, accounts, covenants, contracts, agreements, damages, and any and all claims, defenses, demands, and liabilities whatsoever of every name, and nature, both in law or in equity, which the RELEASORS now have or ever had against the RELEASEES, from the beginning of time to the date of this Release, arising out of, related to, or connected with the Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of April 1, 2006 (hereinafter referred to as the “CLA”), or the Event of Default, Notice of Default, Notice of Partial Termination or Licensed Intellectual Property as they are defined in the Settlement Agreement and First Amendment to Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of September 21, 2007 (hereinafter referred to as the “Settlement Agreement”), including, without limitation, all claims, counterclaims and defenses asserted, or that could have been asserted, by the RELEASORS in, or in connection with, the litigation captioned Aspen Aerogels, Inc. v. Cabot Corporation, Civil

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 1 of 3

Action No. 2675-N, pending in the Court of Chancery of the State of Delaware in and for New Castle County, and all claims, counterclaims and defenses asserted, that could have been asserted, or that could be asserted in the future by the RELEASORS arising out of, related to, or connected with the validity or enforceability of (a) any the Aspen Issued Patents, (b) any patent that actually is issued to or acquired by Aspen on or before July 1, 2007 on account of one or more of the licensed Patent Applications and Acquired Patents, or (c) any foreign counterparts of the patents referenced in (b), supra, regardless of when they are issued.

By executing this Release, the RELEASORS agree and acknowledge that their representatives have read this document with care and with the advice of counsel, and that no representation of fact or opinion has been made to the RELEASORS by anyone which has induced the RELEASORS in any manner to execute this Release.

Capitalized terms used in this Release but not otherwise defined shall have the meanings attributed to them in the CLA and/or the Settlement Agreement.

Nothing herein is intended to, or shall be construed to, release or discharge any obligations for future performance, or restrictions imposed upon any rights granted, under the CLA, as amended, or the Settlement Agreement.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 2 of 3

In WITNESS HEREOF, the RELEASERS have caused this release to be executed their duly authorized representatives this             day of September, 2007.

CABOT CORPORATION
By:
	Name:
	Title:
WITNESS
Name:
Title:

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 3 of 3

Exhibit D

IN THE COURT OF CHANCERY IN THE STATE OF DELAWARE

IN AND FOR NEW CASTLE COUNTY

ASPEN AEROGELS, INC., a Delaware corporation,	)
	)
	)
Plaintiff,	)	C.A. No. 2675-VCL
	)
v.	)
	)
CABOT CORPORATION, a Delaware corporation,	)
	)
	)
Defendant.	)

STIPULATION OF DISMISSAL

Plaintiff Aspen Aerogels, Inc. and defendant Cabot Corporation, constituting all of the parties who have appeared in this proceeding, hereby stipulate, pursuant to Chancery Court Rule 41(a)(1)(ii), that this action, including any and all claims, counterclaims and defenses asserted herein, is hereby dismissed with prejudice and without costs or attorney’s fees to any party.

STIPULATED AND AGREED to by:

John L. Reed (#3023)	William J. Wade (#704)
Paul D. Brown (#3903)	Jennifer J. Veet (#4792)
Joseph B. Cicero (#4388)	Richards, Layton & Finger
Edwards Angell Palmer & Dodge LLP	One Rodney Square
919 North Market Street, 15th Floor	P.O. Box 551
Wilmington, Delaware 19801	Wilmington, DE 19899
Telephone: (302) 777-7770	Telephone: (302) 651-7700
Facsimile: (302) 777-4263	Facsimile: (302) 651-7701
Attorneys for Plaintiff Aspen Aerogels, Inc.	Attorneys for Defendant Cabot Corporation

Date: July             , 2007

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

RELEASE

For good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, Cabot Corporation, on behalf of itself and each of its subsidiaries, divisions, affiliates, corporate parents, joint ventures, partnerships, limited partnerships, predecessors, successors and assigns and each director, officer, general partner, limited partner, employee, servant and agent thereof (hereinafter collectively referred to as the “RELEASORS”), hereby remise, release and forever discharge Aspen Aerogels, Inc., and each of its subsidiaries, divisions, affiliates, joint ventures, partnerships, limited partnerships, and each director, officer, general partner, limited partner, stockholder, holder of indebtedness, employee, servant, agent and attorney thereof (hereinafter collectively referred to as the “RELEASEES”), of and from all debts, demands, actions, causes of action, suits, accounts, covenants, contracts, agreements, damages, and any and all claims, defenses, demands, and liabilities whatsoever of every name, and nature, both in law or in equity, which the RELEASORS now have or ever had against the RELEASEES, from the beginning of time to the date of this Release, arising out of, related to, or connected with the Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of April 1, 2006 (hereinafter referred to as the “CLA”), or the Event of Default, Notice of Default, Notice of Partial Termination or Licensed Intellectual Property as they are defined in the Settlement Agreement and First Amendment to Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of September 21, 2007 (hereinafter referred to as the “Settlement Agreement”), including, without limitation, all claims, counterclaims and defenses asserted, or that could have been asserted, by the RELEASORS in, or in connection with, the litigation captioned Aspen Aerogels, Inc. v. Cabot Corporation, Civil Action No. 2675-N, pending in the Court of Chancery of the State of Delaware in and for New

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 1 of 3

Castle County, and all claims, counterclaims and defenses asserted, that could have been asserted, or that could be asserted in the future by the RELEASORS arising out of, related to, or connected with the validity or enforceability of (a) any the Aspen Issued Patents, (b) any patent that actually is issued to or acquired by Aspen on or before July 1, 2007 on account of one or more of the licensed Patent Applications and Acquired Patents, or (c) any foreign counterparts of the patents referenced in (b), supra, regardless of when they are issued.

By executing this Release, the RELEASORS agree and acknowledge that their representatives have read this document with care and with the advice of counsel, and that no representation of fact or opinion has been made to the RELEASORS by anyone which has induced the RELEASORS in any manner to execute this Release.

Capitalized terms used in this Release but not otherwise defined shall have the meanings attributed to them in the CLA and/or the Settlement Agreement.

Nothing herein is intended to, or shall be construed to, release or discharge any obligations for future performance, or restrictions imposed upon any rights granted, under the CLA, as amended, or the Settlement Agreement.

In WITNESS HEREOF, the RELEASERS have caused this release to be executed their duly authorized representatives this 21st day of September, 2007.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 2 of 3

CABOT CORPORATION
By	/s/ Ravijit Paintal
	Name:	Ravijit Paintal
	Title:	Vice President
WITNESS
/s/ Richard Karpeles
Name:	Richard Karpeles
Title:	Product Line Director FMO

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 3 of 3

RELEASE

In consideration of payment of the sum of One Dollar ($1.00), together with other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, Aspen Aerogels, Inc., on behalf of itself and each of its subsidiaries, divisions, affiliates, corporate parents, joint ventures, partnerships, limited partnerships, predecessors, successors and assigns and each director, officer, general partner, limited partner, employee, servant and agent thereof (hereinafter collectively referred to as the “RELEASORS”), hereby remise, release and forever discharge Cabot Corporation and each of its subsidiaries, divisions, affiliates, joint ventures, partnerships, limited partnerships, and each director, officer, general partner, limited partner, stockholder, holder of indebtedness, employee, servant, agent and attorney thereof (hereinafter collectively referred to as the “RELEASEES”), of and from all debts, demands, actions, causes of action, suits, accounts, covenants, contracts, agreements, damages, and any and all claims, defenses, demands, and liabilities whatsoever of every name, and nature, both in law or in equity, which the RELEASORS now have or ever had against the RELEASEES, from the beginning of time to the date of this Release, arising out of, related to, or connected with the Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of April 1, 2006 (hereinafter referred to as the “CLA”), or the Event of Default, Notice of Default, Notice of Partial Termination or Licensed Intellectual Property as they are defined in the Settlement Agreement and First Amendment to Cross License Agreement between Aspen Aerogels, Inc. and Cabot Corporation, dated as of September 21, 2007 (hereinafter referred to as the “Settlement Agreement”), including, without limitation, all claims, counterclaims and defenses asserted, or that could have been asserted, by the RELEASORS in, or in connection with, the litigation captioned Aspen Aerogels, Inc. v. Cabot Corporation, Civil Action No. 2675-N, pending in the

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 1 of 3

Court of Chancery of the State of Delaware in and for New Castle County, and all claims, counterclaims and defenses asserted, that could have been asserted, or that could be asserted in the future by the RELEASORS arising out of, related to, or connected with the validity or enforceability of (a) any of the Cabot Issued Patents, (b) any patent that actually is issued to or acquired by Cabot on or before July 1, 2007 on account of one or more of the licensed Patent Applications and Acquired Patents, or (c) any foreign counterparts of the patents referenced in (b), supra, regardless of when they are issued.

By executing this Release, the RELEASORS agree and acknowledge that their representatives have read this document with care and with the advice of counsel, and that no representation of fact or opinion has been made to the RELEASORS by anyone which has induced the RELEASORS in any manner to execute this Release.

Capitalized terms used in this Release but not otherwise defined shall have the meanings attributed to them in the CLA and/or the Settlement Agreement.

Nothing herein is intended to, or shall be construed to, release or discharge any obligations for future performance, or restrictions imposed upon any rights granted, under the CLA, as amended, or the Settlement Agreement.

In WITNESS HEREOF, the RELEASERS have caused this release to be executed by their duly authorized representatives this 21st day of September, 2007.

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 2 of 3

ASPEN AEROGELS, INC.
By	/s/ Donald R. Young
	Name:	Donald R. Young
	Title:	President
WITNESS
/s/ Richard M.C. Glenn
Name:	Richard M.C. Glenn
Title:	Secretary

Portions of this Exhibit, indicated by the mark “[***],” were omitted and have been filed separately with the Secretary of the Commission pursuant to the Registrant’s application requesting confidential treatment pursuant to Rule 406 of the Securities Act of 1933, as amended.

Page 3 of 3

EX-21.1

Exhibit 21.1

SUBSIDIARIES OF ASPEN AEROGELS, INC.

Aspen Aerogels Germany GmbH, a German entity

Aspen Aerogels Rhode Island, LLC, a Rhode Island limited liability company

EX-23.1

Exhibit 23.1

Consent of Independent Registered Public Accounting Firm

The Board of Directors

Aspen Aerogels, Inc.:

We consent to the use of our report dated March 25, 2014, except as to notes 1, 9 and 20, which are as of April 28, 2014, with respect to the consolidated balance sheets of Aspen Aerogels, Inc. and subsidiaries as of December 31, 2012 and 2013, and the related consolidated statements of operations, comprehensive income (loss), stockholders’ (deficit) equity, and cash flows for each of the years in the three-year period ended December 31, 2013, included herein and to the reference to our firm under the heading “Experts” in the prospectus.

Our report described above contains an explanatory paragraph that states that the Company has suffered recurring losses and negative cash flows from operations, has a net capital deficiency, and has significant debt maturities that are payable within twelve months that raise substantial doubt about its ability to continue as a going concern. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

/s/ KPMG LLP

Boston, Massachusetts

April 28, 2014

EX-23.3

Exhibit 23.3

Date: April 25, 2014

**Via Email**

Aspen Aerogels, Inc.

30 Forbes Road, Building B

Northborough, MA 01532

CONSENT OF FREEDONIA CUSTOM RESEARCH, INC.

Freedonia Custom Research, Inc. (“Freedonia”) hereby consents to the references to Freedonia’s name in Aspen Aerogels, Inc.’s (the “Company”) Registration Statement on Form S-1 (as may be amended or supplemented) to be filed with the U.S. Securities and Exchange Commission (the “Registration Statement”) and the quotation by the Company in the Registration Statement of research data, information, charts and graphs from Freedonia’s report prepared on behalf of the Company. Freedonia also hereby consents to the filing of this letter as an exhibit to the Registration Statement.

FREEDONIA CUSTOM RESEARCH, INC.
By:	/s/ Andrew Fauver
Name:	Andrew Fauver
Title:	President

Freedonia Custom Research, Inc. Ÿ 767 Beta Drive Ÿ Cleveland, Ohio 44143

Toll Free: (US) 800.927.5900 Ÿ International: 440.684.9600 Ÿ Fax: 440.646.0484

Web: www.freedoniagroup.com Ÿ E-mail: info@freedoniagroup.com

CORRESP

  Sahir Surmeli | 617 348 3013 | ssurmeli@mintz.com One Financial Center Boston, MA 02111 617-542-6000 617-542-2241 fax www.mintz.com

April 28, 2014

VIA EDGAR & OVERNIGHT MAIL

Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

Attention:	Pamela A. Long, Assistant Director
	Erin Jaskot
	John Cash
	Kevin Stertzel
	David Korvin

Re: Aspen Aerogels, Inc.

Draft Registration Statement on Form S-1

Submitted March 25, 2014

CIK No. 0001145986

Ladies and Gentlemen:

We are submitting this letter on behalf of Aspen Aerogels, Inc. (the “Company”) in response to comments from the staff (the “Staff”) of the Securities and Exchange Commission (the “Commission”) received by letter dated April 17, 2014 (the “Comment Letter”) from Pamela A. Long, Assistant Director, to John F. Fairbanks, the Company’s Vice President, Chief Financial Officer and Treasurer, relating to the above-referenced draft registration statement on Form S-1 of the Company initially submitted with the Commission on March 25, 2014 on a confidential basis pursuant to Title I, Section 106 of the Jumpstart Our Business Startups Act (the “Initial Confidential Submission”). In conjunction with this letter, the Company is making amendments to the draft registration statement contained in the Initial Confidential Submission and making its initial public filing of a registration statement on Form S-1 dated the date hereof (the “Registration Statement”) with the Commission.

For convenient reference, we have set forth below in italics each of the Staff’s comments set forth in the Comment Letter and have keyed the Company’s responses to the numbering of the comments and the headings used in the Comment Letter. All of the responses are based on information provided to Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. by representatives of the Company. Where appropriate, the Company has responded to the Staff’s comments by making changes to the disclosure in the Registration Statement. Page numbers referred to in the responses reference the applicable pages of the Registration Statement.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

BOSTON | LONDON | LOS ANGELES | NEW YORK | SAN DIEGO | SAN FRANCISCO | STAMFORD | WASHINGTON

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 2

We are providing by overnight delivery to Ms. Erin Jaskot of the Staff five courtesy copies of this letter and copies of the Registration Statement that have been marked to show changes from the Initial Confidential Submission.

General

1. If you intend to respond to these comments with an amended draft registration statement, please submit it and any associated correspondence in accordance with the guidance we provide in the Division’s October 11, 2012 announcement on the SEC website at http://www.sec.gov/divisions/corpfin/cfannouncements/drsfilingprocedures101512.htm.

Response: The Company respectfully acknowledges the Staff’s comment and advises the Staff that the Company is making its initial public filing of the Registration Statement in conjunction with this letter.

2. Please keep in mind that we may publicly post filing review correspondence in accordance with our December 1, 2011 policy (http://www.sec.gov/divisions/corpfin/cfannouncements/edgarcorrespondence.htm). If you intend to use Rule 83 (17 CFR 200.83) to request confidential treatment of information in the correspondence you submit on EDGAR, please properly mark that information in each of your confidential submissions to us so we do not repeat or refer to that information in our comment letters to you.

Response: The Company respectfully acknowledges the Staff’s comment and confirms that the Company will properly mark any information for which the Company may request confidential treatment pursuant to Rule 83.

3. Please be advised that we will process this filing and any amendments without a price range. Since the price range triggers a number of disclosure matters, we will need sufficient time to process the amendment when it is included. Please understand that its effect on disclosure throughout the document may cause us to raise issues on areas not previously commented upon.

Response: The Company respectfully acknowledges the Staff’s comment and confirms that it will supplementally provide an estimated range of the expected offering price as soon as practicable. The Company further acknowledges that because of the effect of the price range on disclosure throughout the document, the Staff may have additional comments once a price range is provided.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 3

4. We encourage you to file the remaining exhibits, including the legal opinion, as soon as possible. Please understand that we will need adequate time to review these materials before effectiveness.

Response: The Company respectfully acknowledges the Staff’s comment and is filing additional Exhibits 10.1.2 through 10.1.9, 10.5, 10.17, 23.1 and 23.3 with the Registration Statement as well as an additional amendment dated as of March 31, 2014 to its loan and security agreement with Silicon Valley Bank in Exhibit 10.4. The Company is also filing the exhibits previously submitted with the Initial Confidential Submission. The Company will file the remaining exhibits as soon as practicable and further acknowledges that the Staff will need adequate time to review these materials before effectiveness.

5. Please provide us with copies of any artwork or other graphics you intend to use in your prospectus.

Response: The Company acknowledges the Staff’s comment and respectfully advises the Staff that the Company will provide to the Staff a copy of any artwork or other graphics that it intends to use in the prospectus as soon as practicable.

6. Prior to the effectiveness of the registration statement, please arrange to have FINRA call us or provide us with a letter indicating that FINRA has completed its review of the underwriter arrangements for this offering and has no objection.

Response: The Company acknowledges the Staff’s comment and advises the Staff that a review of the underwriting terms is currently pending before FINRA. Prior to the effectiveness of the Registration Statement, the Company will provide the Staff with a copy of the FINRA clearance letter or arrange for a call from FINRA informing the Staff that FINRA has no additional concerns.

7. Please supplementally provide us with copies of all written communications, as defined in Rule 405 under the Securities Act, that you, or anyone authorized to do so on your behalf, present to potential investors in reliance on Section 5(d) of the Securities Act, whether or not they retain copies of the communications. Similarly, please supplementally provide us with any research reports about you that are published or distributed in reliance upon Section 2(a)(3) of the Securities Act of 1933 added by Section 105(a) of the Jumpstart Our Business Startups Act by any broker or dealer that is participating or will participate in your offering.

Response: The Company advises the Staff that it is supplementally providing the Staff with copies of the written communications provided to (but not retained by) potential investors in reliance on Section 5(d) of the Securities Act of 1933, as amended (the “Securities Act”). Further, based upon information received by the Company from the underwriters identified in the Registration Statement, the Company respectfully advises the Staff that no research reports about the Company have been published or distributed in reliance on Section 2(a)(3) of the Securities Act by any broker or dealer that is or will be a participant in the offering.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 4

Table of Contents, page i

8. Please remove the sentence in the paragraph under the table of contents that advises investors that information is current only as of the date of the prospectus. This statement may suggest to investors that you are not responsible for omissions of material facts necessary to make your statements not misleading at the time of sale or contract of sale.

Response: In response to the Staff’s comment, the Company has revised page i of the Registration Statement to remove the sentence that advises investors that information is current only as of the date of the prospectus.

Our Core Market, page 2

9. We note your statement that your two principal products are used by “most” of the world’s largest oil producers, refiners and petrochemical companies. In addition, we note that you cite specific numbers of end users of your products for each of the major end markets, such as 24 of the world’s largest 25 refining companies using your aerogel blankets. Please tell us how you determined this data, including whether these are estimates based on your reasonable belief, as suggested by your disclosure under “Information about End-Use Customers” on page ii. To the extent this disclosure represents estimates, please clearly disclose this fact here and elsewhere where you discuss your end-use customers. Please also tell us how you selected which companies to highlight specifically (such as ExxonMobil, Petrobras, Chevron, etc.). For example, please tell us whether it is by contribution to total revenue, largest customer in each end market, or some other method.

Response: In response to the Staff’s comment, the Company has revised the disclosure that its two principal products are used by “most” of the world’s largest oil producers, refiners and petrochemical companies to now state “many” wherever such statement appears in the Registration Statement. This statement is based on (a) information provided directly to the Company by end-use customers or by direct customers of the Company that installed the products at the end-use customer location and (b) third party data, described below, identifying the world’s largest oil producing companies, refining companies and petrochemical companies. As noted on page ii of the Registration Statement, the Company does not have information about the exact quantities or end markets in which its products will be used or for what purposes. However, the Company engages in regular communications with certain end users of its products, and such communications allow it to confirm that such end users use its products. The Company has been informed that the products are in use by each of the companies identified by name as an end user under the subheading “Our Core Market” in the “Prospectus Summary” in the Registration Statement.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 5

With respect to the other entities comprising the largest oil producing companies, refiners and petrochemical companies described under the subheading “Our Core Market” in the “Prospectus Summary” in the Registration Statement, some of the information is based on the Company’s belief based on information other than direct end user confirmation. Accordingly, the Company has revised the disclosure under the subheading “Our Core Market” in the “Prospectus Summary” to reflect that such information is based on the Company’s belief.

The Company respectfully submits that, based on the Company’s belief with respect to its end-use customers and the data described below, one or both of the Company’s two principal products are in use at 24 of the world’s largest 25 refining companies, 19 of the world’s 20 largest petrochemical companies and 14 of the world’s largest 20 oil producing companies. The world’s largest 25 refining companies were identified in Oil and Gas Journal’s “Refinery Survey” dated December 2, 2013, which lists the world’s largest refining companies ranked by crude capacity. The world’s 20 largest petrochemical companies were identified in Chemical & Engineering News’s “Global 50” ranking dated July 29, 2013, which lists the world’s largest petrochemical companies ranked by chemical sales. The world’s largest 20 oil producing companies were identified in “The World’s Biggest Oil Companies” by Christopher Helman, Forbes, dated November 17, 2013, which lists the world’s largest oil producing companies ranked by production volume. In conjunction with this letter, the Company is supplementally submitting a copy of these surveys to the Staff.

The Company respectfully informs the Staff that the companies that are specifically highlighted as end-use customers in each end-market category listed under the subheading “Our Core Market” in the “Prospectus Summary” in the Registration Statement are the companies that the Company believes are its largest end-use customers, based on total Company revenue in 2013. In each case, the companies are listed in order of estimated revenue, with the largest listed first. In addition, with respect to the offshore oil production end market, the Company also identified by name its largest contractor direct customer, Technip, because Technip is the Company’s largest contractor direct customer and because of the role the Company believes that Technip plays in the selection of the Company’s products for use in subsea projects.

10. We note that you commissioned the research report by Freedonia Custom Research, Inc. Please file a consent from Freedonia pursuant to Rule 436 of Regulation C of the Securities Act or, in the alternative, please tell us why you do not believe you are required to do so.

Response: The Company respectfully advises the Staff that it has filed a consent from Freedonia Custom Research, Inc. as Exhibit 23.3 to the Registration Statement.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 6

11. We note that you cite various industry and scientific statistics, but do not always fully identify the source of the statistics. For example, we note your statement that “[a]ccording to Valero, world refining capacity is projected to increase… ” but you do not identify Valero or the report used to obtain such information, including the date of the report. This is just one example. Please revise your disclosure throughout.

Response: In response to the Staff’s comment, the Company has revised the Registration Statement on pages 2, 3, 4, 84, 85, 86 and 89 to identify the publications and reports used to support industry and scientific statistics, including the dates of such publications and reports.

Prospectus Summary, page 1

12. Please add a cross reference to your introductory paragraph referencing where the glossary can be located. Although you have included a glossary of energy industry terms in Appendix A, please provide context for such terms where they are first used so that an investor may understand your use of such terms. For example, we note your use of abbreviations for certain measurements, such as on page two where you disclose that world refining capacity is “expected to increase approximately 1.5MMBbl/d on average per year from 2013 to 2017.” Without further context, the meaning of this statement is unclear. Please revise your disclosure throughout your prospectus as appropriate.

Response: In response to the Staff’s comment, the Company has revised the Registration Statement on page 1 to include a cross reference where the glossary can be located and on pages 1, 2, 3, 87, 93 and 98 to provide context for terms listed in the glossary when such terms are first used so that an investor may understand the use of such terms.

Overview, page 1

13. We note that you highlight your compound annual revenue growth rate and your total revenue since inception in the third paragraph of the summary. Please balance this disclosure by also prominently disclosing that you have incurred net losses each year since your inception, your total accumulated deficit, that you expect to continue to incur operating losses, and that your independent registered public accounting firm’s report expresses substantial doubt about your ability to continue as a going concern.

Response: The Company acknowledges the Staff’s comment. In response to the Staff’s comment, the Company has revised the third paragraph on page 1 of the Registration Statement to add disclosure that the Company has incurred and expects to continue to incur annual operating losses. In addition, the Company revised the third paragraph of page 1 of the Registration Statement to add that the Company has an accumulated deficit of $332.8 million at December 31, 2013. Further, the Company added additional disclosure in the “Prospectus Summary” under the heading “—Risks Related to Our Business” to highlight that the report of the Company’s registered public accounting firm expresses substantial doubt about the Company’s ability to continue as a going concern. The going concern issue noted by the Company’s auditors does not factor in the effect of this proposed offering and assumes the Company is required to repay certain indebtedness from other sources. The

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 7

Company has added the going concern risk factor as the third bullet, following the risk factors regarding net losses and the Company’s uncertain ability to generate positive cash flow, because the Company does not anticipate any remaining risk related to its ability to continue as a going concern upon completion of this proposed offering and so believes this order is appropriate. In order to mirror this order in the Registration Statement under the heading “Risk Factors,” the Company has also moved the full risk factor related to this matter from the 36^th risk factor identified to the third risk factor identified in the Registration Statement under the heading “Risk Factors — Risks Related to Our Business and Strategy.”

The Offering, page 8

14. To the extent you are dependent on the proceeds of this offering to repay the amount outstanding under your revolving line of credit, which is due June 2014, please clearly state this fact.

Response: In response to the Staff’s comment, the Company respectfully submits that the Company does not believe it is dependent on the proceeds of this offering to repay the amount outstanding under its revolving line of credit. The Company is pursuing a range of alternatives for repayment in the event that this offering does not occur, including through a new revolving line of credit, extension of the existing revolving line of credit, or the issuance of additional debt or private equity. In addition, the Company has already extended the term of the existing revolving line of credit so that it is now due in July 2014, rather than June 2014, and the Company has revised the disclosure in the Registration Statement on pages 8, 25, 41, 68, 69, 72, 82, 146, F-9, F-25 and F-39 to so reflect.

Risk Factors page 14

Our contracts with U.S. government agencies may not be funded by future…, page 27

15. Please disclose the percentage of your revenues that are from your contracts with U.S. government agencies so that investors may understand the significance of this risk.

Response: In response to the Staff’s comment, the Company has revised the disclosure in the Registration Statement on page 27 to disclose the percentage of the Company’s revenues that are derived from its contracts with U.S. government agencies.

Use of Proceeds, page 41

16. Please disclose the amount of other funds necessary to accomplish the purposes for which the proceeds of the offering are to be used, including the sources of such funds. See Instruction 3 to Item 504 of Regulation S-K.

Response: In response to the Staff’s comment, the Company has revised the disclosure in the Registration Statement on page 41.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 8

Business, page 83

17. Please include the financial information about geographic areas that is required by Item 101(d) of Regulation S-K or include a cross-reference to this data in the financial statements.

Response: In response to the Staff’s comment, the Company has revised the disclosure in the Registration Statement on page 84 to include the financial information about geographic areas that is required by Item 101(d) of Regulation S-K.

Markets, page 84

18. With respect to the chart on page 87, please supplementally tell us how you determined that your choices of illustrative project sizes for the different types of plants were appropriate.

Response: The Company respectfully advises the Staff that it used the following process to determine that its choices of illustrative project sizes for the different types of plants were appropriate. The Company reviewed public reports of each type of project over the past three years using public sources such as Oil & Gas Journal, Bloomberg and Power Engineering. These sources provided estimates as to the project cost and production capacity for each such project. Based on this review of public sources, the Company identified three to five projects in each category that the Company believed to be representative of the project type, disregarding projects that (i) were either unusually small or unusually large or (ii) included large amounts of additional project costs that did not appear to be directly part of the facility (for example, roads or other unrelated infrastructure). For each such sample, the Company then calculated the mean project size and rounded down in order to determine the illustrative project size for that project type. In conjunction with this letter, the Company is supplementally submitting a list of the projects considered and copy of the applicable public sources regarding those projects.

19. We note your disclosure on page 87 that the chart of revenue opportunity estimates is “consistent with your [historical] approach.” However, one liquefaction project, which you predict will generate $37 million of revenue, is considerably higher than any project you have listed. Please clarify whether you have previously derived similar revenue from liquefaction plant projects or, if not, why you think you will be able to do so in the future.

Response: The Company has revised the disclosure on page 87 to reflect that it has not engaged in a new-build or large capacity expansion project at a liquefaction plant, and as such, does not have historical experience in this regard. However, based on the sources described in the response to Comment 18 above, the Company believes the illustrative revenue opportunity from such a project of the scale described in the chart on page 87 would approximate $37 million.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 9

Our Solution, page 88

20. In order to allow investors to better assess your growth prospects, please consider disclosing the life cycle range of your key products in the various applications for which they are employed. For example, we note your products are used in energy insulation markets. It’s not clear if your products are capable of performing as intended for the entire life of the energy infrastructure assets or if your products will need to be replaced at regular periodic intervals. Consequently, it’s not clear if your sales are dependent upon new installations of your products at locations where your product is not currently employed or if your business will periodically generate sales from repeat business at locations where your product is currently installed.

Response: The Company respectfully acknowledges the comment. Substantially all of the Company’s product revenue to date has been, and over the next several years the Company believes substantially all of its product revenue will be, derived from new construction, major capital expansion projects and maintenance on facilities using traditional insulation materials where, in each case, the Company’s products have not been replacing the Company’s previously installed insulation.

The Company respectfully informs the Staff that although the Company’s insulation products and competitive materials are designed to last more than 10 years, the Company believes that end-use customers utilizing insulation in large-scale energy infrastructure facilities routinely remove and replace insulation materials in advance of such periods as part of their ongoing maintenance and operational cycles at such facilities. As a result, in the longer term, the Company does expect that there will be sales opportunities in connection with the replacement of its previously installed aerogel products, however, these will be based on the maintenance schedules and needs of the Company’s end users. Consequently, the Company is currently unable to estimate the timing or scope of such opportunities, although the Company does not believe that its business in dependent on such opportunities. The Company has added additional disclosure on page 89 to indicate that substantially all of its product revenue to date has been, and over the next several years will be, derived from new construction, major capital expansion projects and maintenance on facilities using traditional insulation materials where, in each case, the Company’s products have not been replacing previously installed Aspen Aerogels insulation.

Intellectual Property, page 101

21. We note your disclosure regarding certain patents that you consider important to your business and their expiration dates. Please disclose the particular patents and their importance to your business. See Item 101(c)(iv) of Regulation S-K.

Response: In response to the Staff’s comment, the Company has revised the relevant disclosure on page 101 to disclose the patents that the Company considers important to its business.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 10

Competition, page 103

22. Please supplementally disclose how you determined that your “market share has grown at a rapid rate in recent years” in the second paragraph on page 104. We note that your market share of the energy infrastructure market in 2010 was 1.8% and in 2013 it was 3.1%.

Response: In response to the Staff’s comment, the Company has revised the relevant disclosure on page 104 to delete this statement.

Executive and Director Compensation, page 114

Narrative Disclosure to Summary Compensation Table, page 115

23. Please disclose the material terms of the option awards made in 2013. Please also indicate the portion of the 2013 option awards attributable to new grants versus the portion issued in exchange for the forfeiture of options. See Item 402(o)(4) of Regulation S-K.

Response: In response to the Staff’s comment, the Company has revised the relevant disclosure on page 116 and has also added similar disclosure with regards to director compensation on page 124.

Certain Relationships and Related Persons, Transactions, page 126

Convertible Notes and Warranty Financings, page 126

24. Please disclose Arcapita Venture I Limited’s discount rate for shares or provide a cross-reference where the discount factor can be found in the financial notes for the December 2011 Convertible Note Financing, the June 2012 Convertible Note Financing, and the 2013 Convertible Note and Warrant Financing. Additionally, please ensure that this reference is reflected in your principal stockholders table. See Item 404(a)(6) of Regulation S-K.

Response: The Company respectfully informs the Staff that the Company issued non-interest bearing notes to Arcapita Ventures I Limited (“Arcapita”) due to investment restrictions on Arcapita’s ability to acquire interest-bearing securities, but these notes were intended to yield the same economic result upon an initial public offering as the interest-bearing convertible notes issued to investors who are not subject to such restrictions.

For the holders of interest-bearing convertible notes, the total dollar amount being converted varies daily because the interest accrued on such principal is also converted into shares of common stock, but the discount rate of 62.5% for the entire principal and interest amount being converted shares of common stock is fixed. For Arcapita, the total dollar amount of

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 11

notes it will cancel in exchange for acquiring the Company’s common stock remains fixed because the notes do not bear interest. However, the discount rate varies daily and the variation in discount rate is formulated so as to result in the same aggregate number of shares being acquired by Arcapita for each fixed amount of principal as would be acquired by a holder of the interest-bearing convertible notes for the same amount of principal (and the concurrent conversion of the interest accrued on such principal). In order to achieve this result, the discount rate for the exchange of shares of common stock by Arcapita at the time of an initial public offering by the Company is calculated based on a formula comprised of two components. The first component of the discount rate is the same discount rate applicable to the interest-bearing notes that were issued on such date to the other note holders, which is currently, and will remain at, 62.5%. The second component results in additional discount that accretes on a daily basis and which ensures Arcapita receives additional shares, despite having not accrued any interest on its non-interest-bearing note, such that the number of shares of common stock received by Arcapita equal the number of shares of common stock into which an interest-bearing convertible note (which accrue interest at 8% per annum) of equal principal amount and of same issue date would have converted.

Because the Arcapita discount rate varies daily and because the end result of the variance is to yield an equivalent number of shares to the number of shares issuable to the interest-bearing convertible notes upon conversion of the same principal amount and their associated accrued interest, the Company respectfully submits that a presentation of the full list of possible Arcapita discount rates, which includes a separate rate for each date between the date of issuance and the maturity date of the notes, would not be meaningful to an investor and may be confusing. Instead, the Company respectfully submits that the discussion indicating that Arcapita will receive approximately the number of shares it would have received had it held the same interest-bearing convertible notes as the other note holders is a more useful discussion of how the shares of common stock to be issued to Arcapita will be determined.

However, in order to provide more clarity to investors regarding the Arcapita notes, the Company has made the following revisions to its disclosure in the Registration Statement:

• Under the heading “Certain Relationships and Related Person Transactions” on pages 129 to 131, the Company has clarified that Arcapita’s receipt of shares of the Company’s common stock upon completion of the proposed offering in exchange for the cancellation of the notes issued to Arcapita will be at a discount rate that would result in Arcapita receiving an amount of shares of common stock equivalent to a convertible note that bore interest at the same interest rate and converted at the same conversion price as the Company’s convertible notes.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 12

• Under the heading “Certain Relationships and Related Person Transactions” on pages 129 to 131, the Company has provided the discount rate for each outstanding Arcapita note as of an assumed closing date of the Company’s proposed public offering.

• Under the heading “Principal Stockholders” on page 134, the Company has revised the discussion prior to the principal stockholder table to state that Arcapita’s receipt of shares of the Company’s common stock upon completion of the proposed offering in exchange for the cancellation of the notes issued to Arcapita will be at a discount rate that would result in Arcapita receiving an amount of shares of common stock equivalent to a convertible note that bore interest at the same interest rate and converted at the same conversion price as the Company’s convertible notes.

25. We note your disclosure that Arcapita Ventures I Limited will purchase common stock immediately prior to the offering based on the initial public offering price, subject to a discount factor. Please advise whether Arcapita Ventures I Limited will purchase shares that are being registered on this registration statement, or if it is purchasing shares in a separate private placement, or otherwise. Please also advise whether the arrangement for Arcapita to purchase shares based on the initial public offering price was negotiated at the time of the various convertible note financings or at some other time.

Response: The Company respectfully informs the Staff that in order to ensure that each non-interest-bearing note held by Arcapita Ventures I Limited (“Arcapita”) provides the same economic result as the interest bearing, convertible notes held by the other note holders who participated in each such simultaneous convertible note financing, Arcapita agreed at the time of the purchase of each note that upon the Company’s initial public offering, each such note will be cancelled and Arcapita will receive a number of shares of common stock determined using the formula described above in the Company’s response to Comment No. 24. The result of such formula is that Arcapita will purchase the same number of shares of common stock as the number of shares of common stock into which an interest-bearing, convertible note, issued at the same time and for the same principal amount as the respective Arcapita note, would convert. Each of these agreements was negotiated and entered into by the Company and Arcapita simultaneously with the respective convertible note financing and the issuance of the respective Arcapita note. The sale of shares of common stock to be purchased by Arcapita is not being registered pursuant to the Registration Statement. Instead, such sale will be made by means of a private placement pursuant to Section 4(a)(2) of the Securities Act.

Principal Stockholders, page 132

26. We note that footnote (2) to the principal stockholders table includes a third romanette but discloses only two transactions. Please disclose the third transaction or revise this footnote to reflect that there are only two relevant transactions with respect to GKFF Ventures I, LLC’s stock ownership.

Response: In response to the Staff’s comment, the Company has revised footnote (2) on page 135 to reflect there are only two relevant transactions with respect to GKFF Ventures I, LLC’s beneficial ownership.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 13

Financial Statements

Note (2) – Summary of Basis of Presentation and Significant Accounting Policies, page F-9

Inventories – Page F-11

27. We note your policy disclosure indicates you allocate manufacturing overheads to the cost of conversion based on normal capacity of the company’s production facility. We note elsewhere in your document that your production capacity since March 2011 is currently 40-44 million square feet of aerogel blankets. However, we note your actual production in the years presented may have been substantially less than your stated production capacity during those periods. Please tell us how you have considered the guidance of ASC 330-10-30-6 in your determination of costs allocated to inventory.

Response: In response to the Staff’s comment, the Company respectfully advises the Staff that in connection with valuing inventories, the Company allocates (i) variable production overhead to each unit of production based on the actual use of the production facilities and (ii) fixed production overhead to the costs of conversion based on the normal capacity of the production facility.

At each reporting period, the Company analyzes actual manufacturing compared to normal capacity of the production facility. For periods where actual manufacturing results in an abnormally low or idle production capacity, the Company expenses excess fixed overhead costs as a period cost. For periods where actual manufacturing results exceed normal capacity, the Company decreases the amount of fixed overhead per unit so that inventories are not measured above cost.

During the years ended December 31, 2011 and 2012, the Company ascertained that actual production levels fell below its normal capacity. As a result, the excess fixed overhead was recognized as an expense in the period in which it was incurred. During the year ended December 31, 2013, the Company met and exceeded normal capacity. As a result, the amount of fixed overhead allocated to each unit of production was decreased and inventories were not measured at above cost.

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 14

Subsequent Events

28. We are unable to locate a footnote within your financial statements indicating you have evaluated subsequent events, including the date through which subsequent events have been evaluated. Please refer to ASC 855-10-50-1 and provide the requisite disclosures.

Response: In response to the Staff’s comment, the Company has added Note 20 “Subsequent Events” to the Company’s consolidated financial statements included in the Registration Statement to properly disclose that the Company had evaluated subsequent events up through March 25, 2014 which was the date the consolidated financial statements were issued. The Company has also updated the disclosure to appropriately disclose events that have occurred subsequent to the initial filing.

Exhibit Index

29. We note you plan to request confidential treatment for Exhibit 10.17. To the extent that we have comments on your request, please note that we will issue them in a separate letter. Please further note that all comments on your request must be resolved before we will accelerate the effective date of your registration statement.

Response: In response to the Staff’s comment, the Company respectfully advises the Staff that the Company has filed the Cross License Agreement dated as of April 1, 2006 by and between Cabot Corporation and the Company, as amended, as Exhibit 10.17 to the Registration Statement and is submitting a confidential treatment request with regards to Exhibit 10.17 in conjunction with this letter.

30. We note you have filed Exhibit 10.1.1 as Exhibit 10.11 and Exhibit 10.11 as Exhibit 10.1.1. Please correctly file these exhibits in your next filing.

Response: In response to the Staff’s comment, the Company respectively advises that it has revised the exhibits such that it has correctly filed Exhibits 10.1.1 and Exhibit 10.11 with the Registration Statement.

*        *        *         *        *

Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.

April 28, 2014

Page 15

When appropriate, the Company will provide a written request for acceleration of the effective date of the Registration Statement and will include the requested “Tandy” language therein. The Company and the Underwriters are aware of their respective obligations under Rules 460 and 461 regarding requesting acceleration of the effectiveness of the Registration Statement.

We hope that the above responses and the related revisions reflected in the Registration Statement will be acceptable to the Staff. Please do not hesitate to call me, Thomas R. Burton III or John T. Rudy of this firm at (617) 542-6000 with any comments or questions regarding the Registration Statement and this letter. We thank you for your time and attention.

Sincerely,

/s/ Sahir Surmeli

Sahir Surmeli

cc:	Securities and Exchange Commission
	Erin Jaskot
	John Cash
	Kevin Stertzel
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	Aspen Aerogels, Inc.
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	Thomas R. Burton III
	John T. Rudy
	Simpson Thacher & Bartlett LLP
	Roxane Reardon
	Benjamin Wells
	KPMG LLP
	Kristin L. Fraser