SC 13D

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C.  20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

RELYPSA, INC.

(Name of Issuer)

COMMON STOCK

(Title of Class of Securities)

759531106

(CUSIP Number)

OrbiMed Advisors LLC

OrbiMed Capital GP IV LLC

Samuel D. Isaly

601 Lexington Avenue, 54th Floor

New York, NY 10022

Telephone:  (212) 739-6400

(Name, Address and Telephone Number of Person

Authorized to Receive Notices and Communications)

November 20, 2013

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of § 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box o.

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits.  See § 240.13d-7(b) for other parties to whom copies are to be sent.

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 759531106 Page 2 of 12 Pages

1	NAME OF REPORTING PERSONS OrbiMed Advisors LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) o
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)			o
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 9,941,551
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 9,941,551
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 9,941,551
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)			o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 33.48%*
14	TYPE OF REPORTING PERSON (See Instructions) IA

_____________________________

*This percentage is calculated based upon 29,692,299 shares of the Issuer’s Common Stock (defined below) outstanding, which includes the exercise in full by the underwriters of the Issuer’s initial public offering of their option to purchase 1,027,500 newly issued Common Stock acquired in the Issuer’s initial public offering, as set forth in the Issuer’s Form S-1 filed with the SEC (defined below) on November 14, 2013.

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SCHEDULE 13D

CUSIP No. 759531106 Page 3 of 12 Pages

1	NAME OF REPORTING PERSONS OrbiMed Capital GP IV LLC
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) o
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)			o
6	CITIZENSHIP OR PLACE OF ORGANIZATION Delaware
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 9,941,551
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 9,941,551
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 9,941,551
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)			o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 33.48%*
14	TYPE OF REPORTING PERSON (See Instructions) OO

_________________________

*This percentage is calculated based upon 29,692,299 shares of the Issuer’s Common Stock outstanding, which includes the exercise in full by the underwriters of the Issuer’s initial public offering of their option to purchase 1,027,500 shares of newly issued Common Stock acquired in the Isser’s inital public offering, as set forth in the Issuer’s Form S-1 filed with the SEC on November 14, 2013.

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SCHEDULE 13D

CUSIP No. 759531106 Page 4 of 12 Pages

1	NAME OF REPORTING PERSONS Samuel D. Isaly
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (See Instructions) (a) o (b) o
3	SEC USE ONLY
4	SOURCE OF FUNDS (See Instructions) N/A
5	CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) or 2(e)			o
6	CITIZENSHIP OR PLACE OF ORGANIZATION United States
NUMBER OF SHARES BENEFICIALLY OWNED BY EACH REPORTING PERSON WITH		7	SOLE VOTING POWER 0
		8	SHARED VOTING POWER 9,941,551
		9	SOLE DISPOSITIVE POWER 0
		10	SHARED DISPOSITIVE POWER 9,941,551
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON 9,941,551
12	CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (See Instructions)			o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11) 33.48%*
14	TYPE OF REPORTING PERSON (See Instructions) IN

____________________________

*This percentage is calculated based upon 29,692,299 shares of the Issuer’s Common Stock outstanding, which includes the exercise in full by the underwriters of the Issuer’s initial public offering of their option to purchase 1,027,500 shares of newly issued Common Stock aquired in the Issuer’s initial public offering, as set forth in the Issuer’s Form S-1 filed with the SEC on November 14, 2013.

                          

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Item 1. Security and Issuer

This Schedule 13D (the “Statement”) relates to the common stock of Relypsa, Inc. (the “Common Stock”), a corporation organized under the laws of the state of Delaware (the “Issuer”), with its principal executive offices located at 700 Saginaw Drive, Redwood, California 94063.  The Common Stock is listed on the NASDAQ National Market under the ticker symbol “RLYP.”  Information given in response to each item shall be deemed incorporated by reference in all other items, as applicable.

Item 2. Identity and Background

(a)               This Statement is being filed by OrbiMed Advisors LLC (“Advisors”), a limited liability company organized under the laws of Delaware, OrbiMed Capital GP IV LLC (“GP IV”), a limited liability company organized under the laws of Delaware, and Samuel D. Isaly (“Isaly”), an individual (collectively, the “Reporting Persons”).

(b) – (c)               Advisors, a registered investment adviser under the Investment Advisers Act of 1940, as amended, is the sole managing member of GP IV, which is the sole general partner of OrbiMed Private Investments IV, LP (“OPI IV”), which holds shares of Common Stock, as more particularly described in Item 3 below.  Advisors has its principal offices at 601 Lexington Avenue, 54th Floor, New York, New York 10022.

GP IV has its principal offices at 601 Lexington Avenue, 54th Floor, New York, New York 10022.

Isaly, a natural person, owns a controlling interest in Advisors.

The directors and executive officers of Advisors and GP IV are set forth on Schedules I and II, attached hereto.  Schedules I and II set forth the following information with respect to each such person:

(i) name;

(ii) business address;

(iii) present principal occupation or employment and the name, principal business and address of any corporation or other organization in which such employment is conducted;

(iv) citizenship.

(d) – (e)               During the last five years, neither the Reporting Persons nor any Person named in Schedule I or II have been (i) convicted in a criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

(f)               Isaly is a citizen of the United States.

Item 3. Source and Amount of Funds or Other Consideration

On and prior to the close of September 3, 2010, Advisors and GP IV, pursuant to their authority under the limited partnership agreement of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to purchase 22,288,535 shares of Series B-1 Preferred Stock of the Issuer, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration.  Immediately prior to the closing of the Issuer’s initial public offering, each share of Series B-1 Preferred Stock automatically converted into 1.47 shares of Common Stock.

On and prior to the close of July 28, 2011, Advisors and GP IV, pursuant to their authority under the limited partnership agreement of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to purchase 32,778,090 shares of Series B-2 Preferred Stock of the Issuer, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration.   Immediately prior to the closing of the Issuer’s initial public offering, each share of Series B-2 Preferred Stock automatically converted on a 1-for-1 basis into Common Stock.

On and prior to the close of July 26, 2012, Advisors and GP IV, pursuant to their authority under the limited partnership agreement of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to purchase 39,534,346 shares of Series C-1 Preferred Stock of the Issuer, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration. Immediately prior to the closing of the Issuer’s initial public offering, each share of Series C-1 Preferred Stock automatically converted on a 1-for-1 basis into Common Stock.

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On and prior to the close of September 24, 2012, Advisors and GP IV, pursuant to their authority under the limited partnership agreement of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to purchase: (i) 10,676,328 shares of Series C-1 Preferred Stock of the Issuer, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration and (ii) warrants to purchase 21,352,656 shares of Series C-1 Preferred Stock, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration.  Immediately prior to the closing of the Issuer’s initial public offering: (i) each share of Series C-1 Preferred Stock automatically converted on a 1-for-1 basis into Common Stock and (ii) warrants to purchase shares of Series C-1 Preferred Stock were automatically converted on a 1-for-1 basis into warrants to purchase shares of Common Stock.

On and prior to the close of November 30, 2012, Advisors and GP IV, pursuant to their authority under the limited partnership agreement of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to purchase: (i) 1,514,850 shares of Series C-1 Preferred Stock of the Issuer, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration and (ii) warrants to purchase 3,029,700 shares of Series C-1 Preferred Stock, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration.  Immediately prior to the closing of the Issuer’s initial public offering: (i) each share of Series C-1 Preferred Stock automatically converted on a 1-for-1 basis into Common Stock and (ii) warrants to purchase shares of Series C-1 Preferred Stock were automatically converted on a 1-for-1 basis into warrants to purchase shares of Common Stock.

On and prior to the close of October 9, 2013, Advisors and GP IV, pursuant to their authority under the limited partnership agreement of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to purchase: (i) 11,936,659 shares of Series C-2 Preferred Stock of the Issuer, which on and prior to the close of November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration and (ii) warrants to purchase 5,626,696 shares of Series C-2 Preferred Stock, which on and prior to November 13, 2013 underwent a reverse split on a 1-for-17.2 basis, for no additional consideration.  Immediately prior to the closing of the Issuer’s initial public offering: (i) each share of Series C-2 Preferred Stock automatically converted on a 1-for-1 basis into Common Stock and (ii) warrants to purchase shares of Series C-2 Preferred Stock were automatically converted on a 1-for-1 basis into warrants to purchase Common Stock.

On November 14, 2013, the Registration Statement on Form S-1 filed with the Securities and Exchange Commission (the “SEC”) by the Issuer (SEC File No. 333-191437) in connection with its initial public offering of 7,877,500, which includes the exercise in full by the underwriters of the offering of their option to purchase 1,027,500 shares of Common Stock in the Issuer’s initial public offering, was declared effective.

The closing of the offering took place on November 20, 2013, and at such closing Advisors and GP IV, pursuant to their authority under the limited partnership agreements of OPI IV, as more particularly referred to in Item 6 below, caused OPI IV to: (i) purchase 712,192 shares of Common Stock at the initial public offering price of $11.00 per share and (ii) exercise 1,744,711 warrants on a cashless basis to purchase 1,717,429 shares of Common Stock at a strike price of $0.17.

The source of funds for such purchases was the working capital of OPI IV and capital contributions made to OPI IV.

As a result of the transactions described in this Item 3, the Reporting Persons may be deemed to be the beneficial owners of approximately 33.48% of the outstanding shares of Common Stock.  GP IV, as the general partner of OPI IV, may be deemed to be the beneficial owner of approximately 33.48% of the shares of Common Stock.  Advisors, as the managing member of GP IV, may be deemed to be the beneficial owner of approximately 33.48% of the shares of Common Stock.  Isaly, as the owner of a controlling interest in Advisors, may be deemed to be the beneficial owner of approximately 33.48% of the shares of Common Stock.  None of the Reporting Persons have acquired or disposed of any additional shares of Common Stock since November 20, 2013.

Item 4. Purpose of Transaction

The Reporting Persons caused OPI IV to aquire shares of the Issuer for the purpose of making an investment in the Issuer and not with the intention of acquiring control of the Issuer’s business on behalf of OPI IV.

The Reporting Persons from time to time intend to review their investment in the Issuer on the basis of various factors, including the Issuer’s business, financial condition, results of operations and prospects, general economic and industry conditions, the securities markets in general and those for the Issuer’s shares of Common Stock in particular, as well as other developments and other investment opportunities.  Based upon such review, the Reporting Persons will take such actions in the future as the Reporting Persons may deem appropriate in light of the circumstances existing from time to time.  If the Reporting Persons believe that further investment in the Issuer is attractive, whether because of the market price of the Common Stock or otherwise, they may acquire shares of Common Stock or other securities of the Issuer either in the open market or in privately negotiated transactions. Similarly, depending on market and other factors, the Reporting Persons may determine to dispose of some or all of the shares of Common Stock currently owned by the Reporting Persons or otherwise acquired by the Reporting Persons either in the open market or in privately negotiated transactions.

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Except as set forth in this Statement, the Reporting Persons have not formulated any plans or proposals which relate to or would result in: (a) the acquisition by any person of additional securities of the Issuer or the disposition of securities of the Issuer, (b) an extraordinary corporate transaction, such as a merger, reorganization or liquidation, involving the Issuer or any of its subsidiaries, (c) a sale or transfer of a material amount of the assets of the Issuer or any of its subsidiaries, (d) any change in the present Board of Directors or management of the Issuer, including any plans or proposals to change the number or term of directors or to fill any existing vacancies on the board, (e) any material change in the Issuer’s capitalization or dividend policy of the Issuer, (f) any other material change in the Issuer’s business or corporate structure, (g) any change in the Issuer’s charter or bylaws or other instrument corresponding thereto or other action which may impede the acquisition of control of the Issuer by any person, (h) causing a class of the Issuer’s securities to be deregistered or delisted from a national securities exchange or to cease to be authorized to be quoted in an inter-dealer quotation system of a registered national securities association, (i) a class of equity securities of the Issuer becoming eligible for termination of registration pursuant to Section 12(g)(4) of the Act or (j) any action similar to any of those enumerated above.

Item 5. Interest in Securities of the Issuer

(a)-(b)               As of the date of this filing, Advisors, GP IV and Isaly may be deemed, for purposes of Rule 13d-3 of the Act, directly or indirectly, including by reason of their mutual affiliation, to be the beneficial owners of the shares of Common Stock described in Item 3 above.  Based upon information contained in the most recent available filing by the Issuer with the SEC, such Common Stock constitutes approximately 33.48% of the issued and outstanding shares of Common Stock.  Advisors, pursuant to its authority as the sole managing member of GP IV, the sole general partner of OPI IV, may be deemed to indirectly beneficially own the shares of Common Stock held by OPI IV.   GP IV, pursuant to its authority as the general partner of OPI IV, may be deemed to indirectly beneficially own the shares of Common Stock held by OPI IV.  Isaly, pursuant to his authority as the managing member of Advisors and owner of a controlling interest in Advisors, pursuant to its limited liability company agreement, may also be deemed to indirectly beneficially own the shares of Common Stock attributable to Advisors.  As a result, Isaly, Advisors and GP IV share the power to direct the vote and to direct the disposition of the shares of Common Stock described in Item 3 above.

(c) Except as disclosed in Item 3, the Reporting Persons have not effected any transactions in the shares during the past sixty (60) days.

(d)           Not applicable.

(e)           Not applicable.

Item 6. Contracts, Arrangements, Understandings or Relationship with Respect to Securities of the Issuer

In addition to the relationships between the Reporting Persons described in Items 2, 3 and 5 above, GP IV is the sole general partner of OPI IV, pursuant to the terms of the limited partnership agreement of OPI IV. Advisors is the sole managing member of GP IV, pursuant to the terms of the limited liability company agreement of GP IV.  Pursuant to these agreements and relationships, Advisors and GP IV have discretionary investment management authority with respect to the assets of OPI IV.  Such authority includes the power of GP IV to vote and otherwise dispose of securities purchased by OPI IV.  The number of outstanding shares of Common Stock attributable to OPI IV is 9,941,551 shares of Common Stock.  Advisors may be considered to hold indirectly 9,941,551 shares of Common Stock, and GP IV may be considered to hold indirectly 9,941,551 shares of Common Stock.

Jonathan Silverstein (“Silverstein”), a member of Advisors, has been a member of the Board of Directors of the Issuer since August 2010, and, accordingly, the Reporting Persons may have the ability to affect and influence control of the Issuer.  On July 24, 2013, Silverstein was the recipient of a grant of options to purchase 10,140 shares of Common Stock.  From time to time, Silverstein may receive additional stock options or other awards of equity-based compensation pursuant to the Issuer’s compensation arrangements for non-employee directors. Pursuant to an agreement with the Reporting Persons, Silverstein is obligated to transfer any shares of Common Stock issued under any such stock options or other awards to the Reporting Persons, which will distribute such Shares to OPI IV.

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Lock-up Agreement

In connection with OPI IV's purchase of 712,192 shares of newly issued Common Stock in the inital public offering, Morgan Stanley & Co. LLC (“Morgan Stanley”), Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”) and Cowen and Company, LLC and OPI IV entered into a Lock-Up Agreement (the “Lock-Up Agreement”). The Lock-Up Agreement provides that, subject to limited exceptions, without the prior written consent of each of Morgan Stanley and Merrill Lynch, OPI IV will not for a period of 180 days from the date of the Issuer’s prospectus relating to its initial public offering (the “Lock-Up Period”) (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock beneficially owned (as such term is used in Rule 13d-3 of the Act), by OPI IV or any other securities so owned convertible into or exercisable or exchangeable for Common Stock or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise.

After the Lock-Up Agreement expires, OPI IV’s shares of Common Stock will be eligible for sale in the public market, subject to any applicable limitations under Rule 144 under the Securities Act of 1933, as amended (the “Securities Act”) and other applicable United States securities laws. OPI IV, along with other holders of approximately 22.0 million shares of the Issuer’s Common Stock, or approximately 76.7% of the total outstanding Common Stock as of October 10, 2013, will be entitled to rights with respect to the registration of their shares, subject to vesting schedules and to certain other lock-up agreements. Registration of these shares would result in the shares becoming freely tradable without restriction, except for shares purchased by affiliates.

The foregoing description of the Lock-Up Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Lock-Up Agreement, a copy of which is filed as Exhibit 2 and incorporated herein by reference.

Second Amended and Restated Investor Rights Agreement

OPI IV and certain other stockholders of the Issuer entered into a second amended and restated investor rights agreement with the Issuer (“Investor Rights Agreement”) in connection with the purchase of the Issuer’s convertible preferred stock. Pursuant to the Investor Rights Agreement and subject to the terms and conditions therein, the parties agreed that:

Demand Registration Rights

After the expiration of the 180-day period following the completion of the Issuer’s initial public offering, the holders of at least 55% of the shares covered by the Investor Rights Agreement (including shares issuable upon exercise of warrants), or their transferees, can, on not more than two occasions, request that the Issuer register all or a portion of their shares. Such request for registration must cover a number of shares with an anticipated aggregate offering price of at least $10.0 million. The Issuer will not be required to effect a demand registration during the 180 days following the effectiveness of a company-initiated registration statement relating to an initial public offering of its securities, provided that the Issuer has complied with certain notice requirements to the holders of these shares.

Piggyback Registration Rights

The Investor Rights Agreement further provides that, in the event that the Issuer determines to register any of its securities under the Securities Act, either for its own account or for the account of other security holders, the stockholders who are party to the Investor Rights Agreement, including OPI IV, will be entitled to certain “piggyback” registration rights allowing the holders to include their shares in such registration, subject to certain marketing and other limitations. These rights do not apply with respect to a registration related to employee benefit plans, the offer and sale of debt securities, or corporate reorganizations or certain other transactions.

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Form S-3 Registration Rights

After the expiration of a 180-day period following the completion of the Issuer’s initial public offering, the stockholders who are party to the Investor Rights Agreement, including OPI IV, will be entitled to make a written request that the Issuer register their shares on Form S-3 if the Issuer is eligible to file a registration statement on Form S-3 and if the aggregate price to the public of the shares offered is at least $2.0 million. These stockholders may make an unlimited number of requests for registration on Form S-3, subject to specified exceptions.

Expenses of Registration

The Issuer will pay the registration expenses of the holders of the shares registered pursuant to the demand, piggyback and Form S-3 registration rights described above.

Termination of Registration Rights.

OPI IV’s demand, piggyback and Form S-3 registration rights described above generally will terminate upon the earlier of: (i) the date three years following the Issuer’s initial public offering; or (ii) such time as the Issuer has completed its initial public offering and all Registrable Securities, as further defined in the Investor Rights Agreement, of the Issuer held by OPI IV may be sold pursuant to Rule 144 during any ninety (90) day period.

The foregoing description of the Investor Rights Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Investor Rights Agreement, a copy of which is filed as Exhibit 3 and incorporated herein by reference.

Other than as described in this Schedule 13D, to the best of the Reporting Persons’ knowledge, there are no other contracts, arrangements, understandings or relationships (legal or otherwise) among the persons named in Item 2 and between such persons and any person with respect to any securities of the Issuer.

Item 7. Materials to Be Filed as Exhibits

Exhibit	Description
1.	Joint Filing Agreement among OrbiMed Advisors LLC, OrbiMed Capital GP IV LLC and Samuel D. Isaly
2.	Form of Lock-Up Letter Agreement
3.	Second Amended and Restated Investor Rights Agreement

9

SIGNATURE

After reasonable inquiry and to the best of each of the undersigned’s knowledge and belief, each of the undersigned certifies that the information set forth in this statement is true, complete and correct.

Dated:  December 2, 2013

OrbiMed Advisors LLC a Delaware Limited Liability Company
By:	/s/ Samuel D. Isaly
	Name:	Samuel D. Isaly
	Title:	Managing Member

OrbiMed Capital GP IV LLC a Delaware Limited Liability Company
By:	OrbiMed Advisors LLC A Delaware Limited Liability Company and its Managing Member
By:	/s/ Samuel D. Isaly
	Name:	Samuel D. Isaly
	Title:	Managing Member

By:	/s/ Samuel D. Isaly
	Name:	Samuel D. Isaly

10

Schedule I

The name and present principal occupation of each of the executive officers and directors of OrbiMed Advisors LLC are set forth below.  Unless otherwise noted, each of these persons are United States citizens and have as their business address 601 Lexington Avenue, 54th Floor, New York, NY 10022.

Name	Position with Reporting Person	Principal Occupation
Samuel D. Isaly	Managing Member	Managing Member OrbiMed Advisors LLC
Michael B. Sheffery	Member	Member OrbiMed Advisors LLC
Carl L. Gordon	Member	Member OrbiMed Advisors LLC
Sven H. Borho German and Swedish Citizen	Member	Member OrbiMed Advisors LLC
Jonathan T. Silverstein	Member	Member OrbiMed Advisors LLC
W. Carter Neild	Member	Member OrbiMed Advisors LLC
Geoffrey C. Hsu	Member	Member OrbiMed Advisors LLC
Evan D.  Sotiriou	Chief Financial Officer	Chief Financial Officer OrbiMed Advisors LLC

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Schedule II

The business and operations of OrbiMed Capital GP IV LLC are managed by the executive officers and directors of its managing member, OrbiMed Advisors LLC, set forth on Schedule I attached hereto.

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EXHIBIT INDEX

Exhibit	Description
1.	Joint Filing Agreement among OrbiMed Advisors LLC, OrbiMed Capital GP IV LLC and Samuel D. Isaly
2.	Form of Lock-Up Letter Agreement
3.	Second Amended and Restated Investor Rights Agreement

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EX-99.1

EXHIBIT 1

JOINT FILING AGREEMENT

The undersigned hereby agree that the Statement on this Schedule 13D, dated December 2, 2013 (the “Schedule 13D”), with respect to the Common Stock, of Relypsa, Inc. is filed on behalf of each of us pursuant to and in accordance with the provisions of Rule 13d-1(k) under the Securities and Exchange Act of 1934, as amended, and that this Agreement shall be included as an Exhibit to this Schedule 13D.  Each of the undersigned agrees to be responsible for the timely filing of the Schedule 13D, and for the completeness and accuracy of the information concerning itself contained therein.  This Agreement may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned have executed this Agreement as of the 2nd day of December, 2013.

OrbiMed Advisors LLC a Delaware Limited Liability Company
By:	/s/ Samuel D. Isaly
	Name:	Samuel D. Isaly
	Title:	Managing Member

OrbiMed Capital GP IV LLC a Delaware Limited Liability Company
By:	OrbiMed Advisors LLC A Delaware Limited Liability Company and its Managing Member
By:	/s/ Samuel D. Isaly
	Name:	Samuel D. Isaly
	Title:	Managing Member

Samuel D. Isaly
By:	/s/ Samuel D. Isaly
	Samuel D. Isaly

EX-99.2

EXHIBIT 2

FORM OF LOCK-UP LETTER

RELYPSA, INC.

LOCK-UP AGREEMENT

, 2013

Morgan Stanley & Co. LLC

Merrill Lynch, Pierce, Fenner & Smith Incorporated

Cowen and Company, LLC

As Representatives of the several

Underwriters listed in Schedule I to

the Underwriting Agreement

c/o Morgan Stanley & Co. LLC

1585 Broadway

New York, NY 10036

c/o Merrill Lynch, Pierce, Fenner & Smith Incorporated

1 Bryant Park

New York, NY 10036

c/o Cowen and Company, LLC

599 Lexington Avenue, 27 th Floor

New York, NY 10022

Ladies and Gentlemen:

The undersigned understands that you, Morgan Stanley & Co. LLC (“Morgan Stanley”), Merrill Lynch, Pierce, Fenner & Smith Incorporated (“Merrill Lynch”) and Cowen and Company, LLC (“Cowen”), as representatives of the several Underwriters (as defined below) (each of Morgan Stanley, Merrill Lynch and Cowen is a “Representative” and together, the “Representatives”) propose to enter into an Underwriting Agreement (the “Underwriting Agreement”) with Relypsa, Inc., a Delaware corporation (the “Company”), providing for the public offering (the “Public Offering”) by the several Underwriters, including the Representatives (the “Underwriters”), of shares (the “Shares”) of the Common Stock, $0.001 par value per share, of the Company (the “Common Stock”).

To induce the Underwriters that may participate in the Public Offering to continue their efforts in connection with the Public Offering, the undersigned hereby agrees that, without the prior written consent of each of Morgan Stanley and Merrill Lynch on behalf of the Underwriters, it will not, during the period commencing on the date hereof and ending 180 days after the date of the final prospectus (the “Restricted Period”) relating to the Public Offering (the “Prospectus”), (1) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock beneficially owned (as such term is used in Rule 13d-3 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”)), by the undersigned or any other securities so owned convertible into or exercisable or exchangeable for Common Stock or (2) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise. The foregoing restrictions shall not apply to: (a) any shares of Common Stock to be sold by the undersigned pursuant to the Underwriting Agreement; (b) transfers or dispositions of the undersigned’s shares of Common Stock (or any security convertible into or exercisable or exchangeable for Common Stock) (i) as a bona fide gift; (ii) to any trust for the direct or indirect benefit of the undersigned or the immediate family of the undersigned; (iii) to any corporation, partnership, limited liability company, investment fund or other entity controlled or managed, or under common control or management by the undersigned or the immediate family of the undersigned;

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(iv) by will, other testamentary document or intestate succession to the legal representative, heir, beneficiary or a member of the immediate family of the undersigned; (v) as distributions to partners, members or stockholders of the undersigned; provided that in the case of any transfer or distribution pursuant to clause (b)(i) through (v), (x) each donee or distributee shall sign and deliver a lock-up letter substantially in the form of this letter and (y) no filing under Section 16(a) of the Exchange Act, reporting a reduction in beneficial ownership of shares of Common Stock, shall be required or shall be voluntarily made during the Restricted Period (other than a filing on a Form 5); (c) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act for the transfer of shares of Common Stock, provided that (i) such plan does not provide for the transfer of Common Stock during the Restricted Period and (ii) to the extent a public announcement or filing under the Exchange Act, if any, is required of or voluntarily made by or on behalf of the undersigned or the Company regarding the establishment of such plan, such announcement or filing shall include a statement to the effect that no transfer of Common Stock may be made under such plan during the Restricted Period; (d) the exercise of options to purchase shares of Common Stock granted under any stock incentive plan or stock purchase plan of the Company, provided that the underlying shares shall continue to be subject to the restrictions on transfer set forth in this agreement and provided further that no filing under Section 16(a) of the Exchange Act shall be required or shall be voluntarily made during the Restricted Period (other than a filing on a Form 5); (e) the exercise (whether for cash, cashless, or net exercise) of warrants to purchase shares of Common Stock (or any security convertible into or exercisable or exchangeable for Common Stock), provided that the underlying shares shall continue to be subject to the restrictions on transfer set forth in this agreement and provided further that, other than in respect of warrants that will expire or automatically exercise by their terms in connection with the Public Offering, no filing under Section 16(a) of the Exchange Act shall be required or shall be voluntarily made during the Restricted Period (other than a filing on a Form 5); (f) the transfer of shares of Common Stock (or any security convertible into Common Stock) to the Company or sold in connection with a vesting event of the Company’s securities or upon the exercise of options to purchase the Company’s securities, on a “cashless” or “net exercise” basis or to cover tax withholding obligations of the undersigned in connection with such vesting or exercise provided that no filing under Section 16(a) of the Exchange Act shall be required or shall be voluntarily made during the Restricted Period (other than a filing on a Form 5); (g) the transfer or disposition of the undersigned’s shares of Common Stock (or any security convertible into or exercisable or exchangeable for Common Stock) that occurs by operation of law, such as pursuant to a qualifie d domestic order or in connection with a divorce settlement provided that each transferee shall sign and deliver a lock-up letter substantially in the form of this letter; (h) the conversion of the outstanding preferred stock of the Company into shares of Common Stock; provided that such shares of Common Stock shall continue to be subject to the restrictions on transfer set forth in this agreement; (i) during the 180 days after the date of the Prospectus, the transfer of shares of Common Stock (or any security convertible into or exercisable or exchangeable for Common Stock) pursuant to a bona fide third party tender offer, merger, consolidation or other similar transaction made to all holders of the Common Stock involving a change of control of the Company; provided that in the event that the tender offer, merger, consolidation or other such transaction is not completed, the Common Stock owned by the undersigned shall remain subject to the restrictions contained in this agreement or (j) the transfer or disposal of shares of Common Stock acquired on the open market following the Public Offering provided that no filing under Section 16(a) of the Exchange Act shall be required or shall be voluntarily made during the Restricted Period (other than a filing on a Form 5). For purposes of this agreement, “immediate family” shall mean any relationship by blood, marriage or adoption, not more remote than first cousin and “change of control” shall mean the consummation of any bona fide third party tender offer, merger, consolidation or other similar transaction the result of which is that any “person” (as defined in Section 13(d)(3) of the Exchange Act), or group of persons, other than the Company, becomes the beneficial owner (as defined in Rules 13d-3 and 13d-5 of the Exchange Act) of 50% of total voting power of the voting stock of the Company. In addition, the undersigned agrees that, without the prior written consent of each of Morgan Stanley and Merrill Lynch on behalf of the Underwriters, it will not, during the Restricted Period, make any demand for or exercise any right with respect to, the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock, other than in connection with a Follow-on Offering (defined below). The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar against the transfer of the undersigned’s shares of Common Stock except in compliance with the foregoing restrictions.

If the undersigned is an officer or director of the Company, the undersigned further agrees that the foregoing provisions shall be equally applicable to any issuer-directed Shares the undersigned may purchase in the offering.

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If the undersigned is an officer or director of the Company, Morgan Stanley and Merrill Lynch agree that, at least three business days before the effective date of any release or waiver of the foregoing restrictions in connection with a transfer of shares of Common Stock, Morgan Stanley and/or Merrill Lynch will notify the Company of the impending release or waiver, and the Company will agree in the Underwriting Agreement to announce the impending release or waiver by press release through a major news service at least two business days before the effective date of the release or waiver. Any release or waiver granted by Morgan Stanley and Merrill Lynch hereunder to any such officer or director shall only be effective two business days after the publication date of such press release. The provisions of this paragraph will not apply if (a) the release or waiver is effected solely to permit a transfer not for consideration and (b) the transferee has agreed in writing to be bound by the same terms described in this letter to the extent and for the duration that such terms remain in effect at the time of the transfer.

In the event that any equity holder other than the undersigned is permitted by Morgan Stanley and Merrill Lynch to sell or otherwise transfer or dispose of shares of the Company’s Common Stock for value, the same percentage of shares of the Company’s Common Stock held by the undersigned (the “Pro-rata Release”) shall be immediately and fully released on the same terms from any remaining lockup restrictions set forth herein; provided, however , that such Pro-rata Release shall not be applied in the event of (a) permission granted to any individual party by Morgan Stanley and Merrill Lynch to sell or otherwise transfer or dispose of shares of the Company’s Common Stock for value in an amount less than or equal to $1,000,000 in aggregate value of the Company’s Common Stock in respect of such party, or (b) any underwritten public offering, whether or not such offering or sale is wholly or partially a secondary offering of the Company’s Common Stock during the restricted period set forth above (the “Underwritten Sale”);provided, however , that the undersigned, to the extent the undersigned has a contractual right to demand or require the registration of the undersigned’s Common Stock or otherwise “piggyback” on a registration statement filed by the Company for the offer and sale of its Common Stock, is offered the opportunity to participate on a basis consistent with such contractual rights in such Underwritten Sale (a “Follow-on Offering”). In the event that any percentage of such Common Stock permitted to be sold or otherwise transferred or disposed for value are subject to any restrictions of the type set forth in clauses (a) through (j) of the second paragraph of this agreement, the same provisos shall be applicable to the release of the same percentage of the Company’s Common Stock held by the undersigned. In the event that the undersigned is released from any of its obligations under this agreement or, by virtue of this agreement, becomes entitled to offer, pledge, sell, contract to sell, or otherwise dispose of any Common Stock (or any securities convertible into Common Stock) prior to the date that is 180 days after the date of the Prospectus, the Representatives shall use their commercially reasonable efforts to provide notification of such to the undersigned within three (3) business days thereof; provided that the failure to provide such notice shall not give rise to any claim or liability against the Representatives or the Underwriters.

The undersigned understands that, if (i) either Morgan Stanley, Merrill Lynch and Cowen, on the one hand, or the Company, on the other hand, informs the other, prior to the execution of the Underwriting Agreement, that it has determined not to proceed with the Public Offering; (ii) the Underwriting Agreement does not become effective by February 14, 2014; (iii) the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Common Stock to be sold thereunder; or (iv) the registration statement filed with the Securities and Exchange Commission in connection with the Public Offering is withdrawn, the undersigned shall be released from all obligations under this agreement. The undersigned understands that the Company and the Underwriters are relying upon this agreement in proceeding toward consummation of the Public Offering. The undersigned further understands that this agreement is irrevocable and shall be binding upon the undersigned’s heirs, legal representatives, successors and assigns.

Whether or not the Public Offering actually occurs depends on a number of factors, including market conditions. Any Public Offering will only be made pursuant to an Underwriting Agreement, the terms of which are subject to negotiation between the Company and the Underwriters.

Very truly yours,

(Name)

(Address)

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EX-99.3

EXHIBIT 3

EXECUTION VERSION

RELYPSA, INC.

SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT

THIS SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT (the “Agreement”) is entered into as of the 26^th day of July, 2012 (the “Effective Date”), by and among RELYPSA, INC., a Delaware corporation (the “Company”) and the investors listed on EXHIBIT A hereto, referred to hereinafter as the “Investors” and each individually as an “Investor.”

RECITALS

WHEREAS, certain of the Investors are purchasing shares of the Company’s Series C-1 Preferred Stock (“Series C-1”) and Series C-2 Preferred Stock (“Series C-2”) pursuant to that certain Series C Preferred Stock and Warrant Purchase Agreement (as may be amended from time to time, the “Purchase Agreement”) of even date herewith (the “Financing”);

WHEREAS, in connection with the Financing, the Company shall amend and restate its Amended and Restated Certificate of Incorporation by filing a further Amended and Restated Certificate of Incorporation of the Company (as may be amended from time to time, the “Restated Charter”), which shall be effective on the Effective Date, in the form attached to the Purchase Agreement, immediately prior to the consummation of the Financing;

WHEREAS, the obligations in the Purchase Agreement are conditioned upon the execution and delivery of this Agreement;

WHEREAS, certain of the Investors (the “Prior Investors”) are holders of the Company’s Series A-1 Preferred Stock (“Series A-1”), Series A Preferred Stock (“Series A”), Series B-1 Preferred Stock (“Series B-1”) and Series B-2 Preferred Stock (“Series B-2”);

WHEREAS, the Prior Investors and the Company are parties to an Amended and Restated Investor Rights Agreement dated September 3, 2010 and as amended (the “Prior Agreement”); and

WHEREAS, certain of the parties to the Prior Agreement, including Prior Investors who are, of the Effective Date, holders of such requisite number of shares necessary to amend the Prior Agreement pursuant to Section 5.5 of the Prior Agreement, desire to amend and restate the Prior Agreement and accept the rights and covenants hereof in lieu of their rights and covenants under the Prior Agreement.

NOW, THEREFORE, in connection with the consummation of the Financing, the Company and the Investors have agreed to the registration rights, information rights, and other rights as set forth below:

SECTION 1. GENERAL.

1.1 Amendment and Restatement of Prior Agreement. The Prior Agreement is hereby amended and restated in its entirety as set forth herein. Such amendment and restatement is effective upon the execution of this Agreement on the date hereof by the Company and certain of the Prior Investors who are party hereto, pursuant to Section 5.5 of the Prior Agreement. Upon such execution, all provisions of, rights granted and covenants made in the Prior Agreement are hereby waived, released and superseded in their entirety and shall have no further force or effect, including, without limitation, all rights of first refusal and any notice period associated therewith otherwise applicable to the transactions contemplated by the Purchase Agreement.

1.2 Definitions. As used in this Agreement the following terms shall have the following respective meanings:

(a) “C-1 Closing” means the C-1 Closing, as defined in the Purchase Agreement.

(b) “C-2 Closing” means the C-2 Closing, as defined in the Purchase Agreement.

(c) “Common Stock” means the Company’s Common Stock, par value of one tenth of one cent ($0.001) per share.

(d) “Exchange Act” means the Securities Exchange Act of 1934, as amended.

(e) “Form S-3” means such form under the Securities Act as in effect on the date hereof or any successor or similar registration form under the Securities Act subsequently adopted by the SEC which permits inclusion or incorporation of substantial information by reference to other documents filed by the Company with the SEC.

(f) “Holder” means any person owning of record Registrable Securities that have not been sold to the public or any assignee of record of such Registrable Securities in accordance with Section 2.9 hereof.

(g) “Initial C-1 Closing” means the Initial C-1 Closing, as defined in the Purchase Agreement.

(h) “Initial Offering” means the Company’s first firm commitment underwritten public offering of its Common Stock registered under the Securities Act.

(i) “Lender” shall mean TriplePoint Capital, LLC

(j) “Lender Warrant” shall mean the warrant issued to the Lender to purchase shares of Series A-1 pursuant to that certain Plain English Warrant Agreement, dated May 22, 2008, as amended from time to time.

(k) “Major Investor” means (a) any Investor who, together with any other Investors that such Investor controls, or is controlled by, or is under common control with, in the aggregate owns at least five percent (5%) of the issued and outstanding shares of Registrable

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Securities (as adjusted for stock splits, dividends, recapitalizations and the like following each of the Initial C-1 Closing and the Subsequent C-1 Closing, (b) Mediphase Venture Partners II Limited Partnership, for so long as it (together with its affiliates) continues to hold all of the shares of Series B-1 Preferred Stock held as of the Effective Date by such persons (as adjusted for stock splits, dividends, recapitalizations and the like) and (c) Sibling Capital Fund I, LLC (“Sibling”), for so long as such Investor (together with its affiliates) holds (i) a number of shares of Series Preferred representing not less than five percent (5%) of the total number of shares of Common Stock issued or issuable upon the conversion or exercise of all outstanding Series Preferred and Convertible Securities (as defined in the Restated Charter) (as adjusted for stock splits, dividends, recapitalizations and the like), and (ii) all of the shares of Series C Preferred Stock held as of the Effective Date by such Investor.

(l) “Preferred Stock” means the Company’s Preferred Stock, par value of one tenth of one cent ($0.001) per share, including the Series A Preferred, Series B Preferred and Series C Preferred.

(m) “Register,” “registered,” and “registration” refer to a registration effected by preparing and filing a registration statement in compliance with the Securities Act, and the declaration or ordering of effectiveness of such registration statement or document.

(n) “Registrable Securities” means (a) Common Stock of the Company issuable or issued upon conversion of the Shares; (b) for purposes of Section 2 (except Sections 2.1 and 2.4) and Section 5 hereof, shares of Common Stock issued or issuable upon conversion of the Preferred Stock issued or issuable upon exercise of the Lender Warrant; (c) for purposes of Section 2 (except Sections 2.1) and Section 5 hereof, shares of Common Stock issued or issuable upon conversion of the Preferred Stock issued or issuable upon exercise of the SVB Warrant; and (d) any Common Stock of the Company issued as (or issuable upon the conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, or in exchange for or in replacement of, such above-described securities. Notwithstanding the foregoing, Registrable Securities shall not include any securities (i) sold by a person to the public either pursuant to a registration statement or Rule 144 or (ii) sold in a private transaction in which the transferor’s rights under Section 2 of this Agreement are not assigned.

(o) “Registrable Securities then outstanding” means the number of shares of the Company’s Common Stock that are Registrable Securities and either (a) are then issued and outstanding or (b) are issuable pursuant to then exercisable or convertible securities.

(p) “Registration Expenses” means all expenses incurred by the Company in complying with Sections 2.2, 2.3 and 2.4 hereof, including, without limitation, all registration and filing fees, printing expenses, fees and disbursements of counsel for the Company, and fees and disbursements of counsel for a single special counsel designated by the majority of the Holders requesting registration (not to exceed seventy-five thousand dollars ($75,000)), blue sky fees and expenses and the expense of any special audits incident to or required by any such registration (but excluding the compensation of regular employees of the Company which shall be paid in any event by the Company).

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(q) “Requisite Holders” means the holders of shares of Series Preferred representing at least fifty-five percent (55%) of the total number of shares of Common Stock into which the outstanding Series Preferred could be converted pursuant to Section 5(a) of Article IV(E) of the Restated Charter, voting together as a single class.

(r) “SEC” or “Commission” means the Securities and Exchange Commission.

(s) “Securities Act” means the Securities Act of 1933, as amended.

(t) “Selling Expenses” means all underwriting discounts and selling commissions applicable to the sale.

(u) “Series A Preferred” means the Series A Preferred Stock, the Series A-1 Preferred Stock of the Company, and any securities of the Company issued as (or issuable upon the conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, or in exchange for or in replacement of, such above-described securities.

(v) “Series B Preferred” means the Company’s Series B-1 Preferred Stock or Series B-2 Preferred Stock and any securities of the Company issued as (or issuable upon the conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, or in exchange for or in replacement of, such above-described securities.

(w) “Series C Preferred” means the Company’s Series C Preferred Stock, Series C-1 Preferred Stock or Series C-2 Preferred Stock and any securities of the Company issued as (or issuable upon the conversion or exercise of any warrant, right or other security which is issued as) a dividend or other distribution with respect to, or in exchange for or in replacement of, such above-described securities.

(x) “Series Preferred” means the Company’s Series A Preferred Stock, Series A-1 Preferred Stock, Series B-1 Preferred Stock, Series B-2 Preferred Stock, Series C Preferred Stock, Series C-1 Preferred Stock and Series C-2 Preferred Stock.

(y) “Shares” means (i) shares of the Company’s Preferred Stock held from time to time by the Investors listed on EXHIBIT A hereto and their permitted assigns and (ii) the Preferred Stock issuable upon exercise of the SVB Warrant, Lender Warrant, and warrants held by the Investors issued prior to the date hereof.

(z) “Special Registration Statement” means (i) a registration statement relating to any employee benefit plan or (ii) with respect to any corporate reorganization or transaction under Rule 145 of the Securities Act, any registration statements related to the issuance or resale of securities issued in such a transaction or (iii) a registration related to stock issued upon conversion of debt securities.

(aa) “Subsequent C-1 Closing” means the Subsequent C-1 Closing, as defined in the Purchase Agreement.

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(bb) “SVB” means Silicon Valley Bank.

(cc) “SVB Warrant” means the warrant issued to SVB to purchase shares of Series A-1 pursuant to that certain Warrant To Purchase Stock, dated July 30, 2008, as amended from time to time.

SECTION 2. REGISTRATION; RESTRICTIONS ON TRANSFER.

2.1 Restrictions on Transfer.

(a) Each Holder agrees not to make any disposition of all or any portion of the Shares or Registrable Securities unless and until:

(i) there is then in effect a registration statement under the Securities Act covering such proposed disposition and such disposition is made in accordance with such registration statement; or

(ii) (A) The transferee has agreed in writing to be bound by the terms of this Agreement and the Company’s Second Amended and Restated Voting Agreement dated as of even date herewith and as amended from time to time (the “Voting Agreement”), (B) such Holder shall have notified the Company of the proposed disposition and shall have furnished the Company with a detailed statement of the circumstances surrounding the proposed disposition, and (C) if reasonably requested by the Company, such Holder shall have furnished the Company with an opinion of counsel, reasonably satisfactory to the Company, that such disposition will not require registration of such shares under the Securities Act. It is agreed that the Company will not require opinions of counsel for transactions made pursuant to Rule 144, except in unusual circumstances. After its Initial Offering, the Company will not require any transferee pursuant to Rule 144 to be bound by the terms of this Agreement if the shares so transferred do not remain Registrable Securities hereunder following such transfer effective as of the date of transfer. Any transfer in violation of this Section 2.1 shall be void.

(b) Notwithstanding the provisions of subsection (a) above, no such restriction shall apply to a transfer by a Holder that is (A) a partnership transferring to its partners, former partners or affiliated funds in accordance with partnership interests, (B) a corporation transferring to a wholly-owned subsidiary or a parent corporation that owns all of the capital stock of the Holder, (C) a limited liability company transferring to its members or former members in accordance with their interest in the limited liability company, (D) an individual transferring to the Holder’s family member or trust for the benefit of an individual Holder or (E) an individual or entity transferring to a transferee satisfying the criteria to be a Major Investor; provided, that, in each case, within ten (10) days after such transfer, the Company is given written notice thereof, and the transferee will agree in writing to be subject to the terms of this Agreement to the same extent as if he were an original Holder hereunder.

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(c) Each certificate representing Shares or Registrable Securities shall be stamped or otherwise imprinted with legends substantially similar to the following (in addition to any legend required under applicable state securities laws):

“THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 (THE “ACT”) AND MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED, ASSIGNED, PLEDGED OR HYPOTHECATED UNLESS AND UNTIL REGISTERED UNDER THE ACT OR SOLD PURSUANT TO AN APPLICABLE EXEMPTION THEREFROM.

THE SALE, PLEDGE, HYPOTHECATION OR TRANSFER OF THE SECURITIES REPRESENTED BY THIS CERTIFICATE IS SUBJECT TO CERTAIN RESTRICTIONS, PROHIBITIONS AND OTHER TERMS AND CONDITIONS OF A CERTAIN INVESTOR RIGHTS AGREEMENT BY AND BETWEEN THE STOCKHOLDER AND THE COMPANY. COPIES OF SUCH AGREEMENT MAY BE OBTAINED UPON WRITTEN REQUEST TO THE SECRETARY OF THE COMPANY.”

(d) The Company shall be obligated to reissue promptly unlegended certificates at the request of any Holder thereof if the Company has completed its Initial Offering and the Holder shall have obtained an opinion of counsel (which counsel may be counsel to the Company) reasonably acceptable to the Company to the effect that the securities proposed to be disposed of may lawfully be so disposed of without registration, qualification and legend; provided that the second legend listed above shall be removed only at such time as the Holder of such certificate is no longer subject to any restrictions hereunder.

(e) Any legend endorsed on an instrument pursuant to applicable state securities laws and the stop-transfer instructions with respect to such securities shall be removed upon receipt by the Company of an order of the appropriate blue sky authority authorizing such removal.

2.2 Demand Registration.

(a) Subject to the conditions of this Section 2.2, if the Company shall receive a written request from the Requisite Holders (the “Initiating Holders”) that the Company file a registration statement under the Securities Act covering the registration of the Registrable Securities then outstanding (a “Qualified Public Offering”), then the Company shall, within thirty (30) days of the receipt thereof, give written notice of such request to all Holders, and subject to the limitations of this Section 2.2 , effect, as expeditiously as reasonably possible (and no later than ninety (90) days from the receipt of the request), the registration under the Securities Act of all Registrable Securities that all Holders request to be registered.

(b) If the Initiating Holders intend to distribute the Registrable Securities covered by their request by means of an underwriting, they shall so advise the Company as a part of their request made pursuant to this Section 2.2 or any request pursuant to Section 2.4 and the Company shall include such information in the written notice referred to in Section 2.2(a) or Section 2.4(a), as applicable. In such event, the right of any Holder to include its Registrable Securities in such registration shall be conditioned upon such Holder’s participation in such underwriting and the inclusion of such Holder’s Registrable Securities in the underwriting to the

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extent provided herein. All Holders proposing to distribute their securities through such underwriting shall enter into an underwriting agreement in customary form with the underwriter or underwriters selected for such underwriting by the Holders of a majority of the Registrable Securities held by all Initiating Holders (which underwriter or underwriters shall be reasonably acceptable to the Company). Notwithstanding any other provision of this Section 2.2 or Section 2.4, if the underwriter advises the Company that marketing factors require a limitation of the number of securities to be underwritten (including Registrable Securities) then the Company shall so advise all Holders of Registrable Securities that would otherwise be underwritten pursuant hereto, and the number of shares that may be included in the underwriting shall be first allocated to the Holders of Series C Preferred on a pro rata basis based on the number of such securities held by all such Holders (including the Initiating Holders), then to the Holders of Series B Preferred on a pro rata basis based on the number of such securities held by all such Holders (including the Initiating Holders), then to the Holders of Series A Preferred on a pro rata basis based on the number of such securities held by all such Holders (including the Initiating Holders). Any Registrable Securities excluded or withdrawn from such underwriting shall be withdrawn from the registration.

(c) The Company shall not be required to effect a registration pursuant to this Section 2.2:

(i) prior to the earlier of (A) the third anniversary of the date of this Agreement or (B) of the expiration of the restrictions on transfer set forth in Section 2.11 following the Initial Offering;

(ii) after the Company has effected two (2) registrations pursuant to this Section 2.2, and such registrations have been declared or ordered effective;

(iii) during the period starting with the date of filing of, and ending on the date one hundred eighty (180) days following the effective date of the registration statement pertaining to the Initial Offering (or such longer period as may be determined pursuant to Section 2.11 hereof); provided that the Company makes reasonable good faith efforts to cause such registration statement to become effective;

(iv) if the anticipated aggregate offering price, net of underwriting discounts and commission, would be less than $10,000,000;

(v) if within thirty (30) days of receipt of a written request from Initiating Holders pursuant to Section 2.2(a), the Company gives notice to the Holders of the Company’s intention to file a registration statement for its Initial Offering within ninety (90) days;

(vi) if the Company shall furnish to Holders requesting a registration statement pursuant to this Section 2.2 a certificate signed by the Chairman of the Board of Directors of the Company (sometimes referred to herein as the “Board”) stating that in the good faith judgment of the Board of Directors of the Company, it would be detrimental to the Company and its stockholders for such registration statement to be effected at such time, in which event the Company shall have the right to defer such filing for a period of not more than

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ninety (90) days after receipt of the request of the Initiating Holders; provided that such right to delay a request shall be exercised by the Company not more than once in any twelve (12) month period;

(vii) if the Initiating Holders propose to dispose of shares of Registrable Securities that may be immediately registered on Form S-3 pursuant to a request made pursuant to Section 2.4 below; or

(viii) in any particular jurisdiction in which the Company would be required to qualify to do business or to execute a general consent to service of process in effecting such registration, qualification or compliance.

2.3 Piggyback Registrations. The Company shall notify all Holders of Registrable Securities in writing at least fifteen (15) days prior to the filing of any registration statement under the Securities Act for purposes of a public offering of securities of the Company (including, but not limited to, registration statements relating to secondary offerings of securities of the Company, but excluding Special Registration Statements) and will afford each such Holder an opportunity to include in such registration statement all or part of such Registrable Securities held by such Holder. Each Holder desiring to include in any such registration statement all or any part of the Registrable Securities held by it shall, within ten (10) days after the above-described notice from the Company, so notify the Company in writing. Such notice shall state the intended method of disposition of the Registrable Securities by such Holder. If a Holder decides not to include all of its Registrable Securities in any registration statement thereafter filed by the Company, such Holder shall nevertheless continue to have the right to include any Registrable Securities in any subsequent registration statement or registration statements as may be filed by the Company with respect to offerings of its securities, all upon the terms and conditions set forth herein.

(a) Underwriting. If the registration statement of which the Company gives notice under this Section 2.3 is for an underwritten offering, the Company shall so advise the Holders of Registrable Securities. In such event, the right of any such Holder to include Registrable Securities in a registration pursuant to this Section 2.3 shall be conditioned upon such Holder’s participation in such underwriting and the inclusion of such Holder’s Registrable Securities in the underwriting to the extent provided herein. All Holders proposing to distribute their Registrable Securities through such underwriting shall enter into an underwriting agreement in customary form with the underwriter or underwriters selected for such underwriting by the Company. Notwithstanding any other provision of this Agreement, if the underwriter determines in good faith that marketing factors require a limitation of the number of shares to be underwritten, the number of shares that may be included in the underwriting shall be allocated, first, to the Company; second, to the Holders of Series C Preferred on a pro rata basis based on the number of such securities held by all such Holders on an as converted to Common Stock basis (including the Initiating Holders); third to the Holders of Series B Preferred on a pro rata basis based on the number of such securities held by all such Holders on an as converted to Common Stock basis (including the Initiating Holders); fourth to the Holders of Series A Preferred on a pro rata basis based on the number of such securities held by all such Holders on an as converted to Common Stock basis (including the Initiating Holders); and fifth to any stockholder of the Company (other than a Holder) on a pro rata basis; provided, however, that

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no such reduction shall reduce the amount of securities of the selling Holders included in the registration below thirty percent (30%) of the total amount of securities included in such registration, unless such offering is the Initial Offering and such registration does not include shares of any other selling stockholders, in which event any or all of the Registrable Securities of the Holders may be excluded in accordance with the immediately preceding clause. In no event will shares of any other selling stockholder be included in such registration that would reduce the number of shares which may be included by Holders without the written consent of Holders of not less than a majority of the Registrable Securities proposed to be sold in the offering. If any Holder disapproves of the terms of any such underwriting, such Holder may elect to withdraw therefrom by written notice to the Company and the underwriter, delivered at least ten (10) business days prior to the effective date of the registration statement. Any Registrable Securities excluded or withdrawn from such underwriting shall be excluded and withdrawn from the registration. For any Holder which is a partnership, limited liability company or corporation, the partners, retired partners, members, retired members and stockholders of such Holder, or the estates and family members of any such partners, retired partners, members and retired members and any trusts for the benefit of any of the foregoing person shall be deemed to be a single “Holder,” and any pro rata reduction with respect to such “Holder” shall be based upon the aggregate amount of shares carrying registration rights owned by all entities and individuals included in such “Holder,” as defined in this sentence.

(b) Right to Terminate Registration. The Company shall have the right to terminate or withdraw any registration initiated by it under this Section 2.3 whether or not any Holder has elected to include securities in such registration. The Registration Expenses of such withdrawn registration shall be borne by the Company in accordance with Section 2.5 hereof.

2.4 Form S-3 Registration. In case the Company shall receive from any Holder or Holders of Registrable Securities a written request or requests that the Company effect a registration on Form S-3 (or any successor to Form S-3) or any similar short-form registration statement and any related qualification or compliance with respect to all or a part of the Registrable Securities owned by such Holder or Holders, the Company will:

(a) promptly give written notice of the proposed registration, and any related qualification or compliance, to all other Holders of Registrable Securities; and

(b) as soon as practicable, effect such registration and all such qualifications and compliances as may be so requested and as would permit or facilitate the sale and distribution of all or such portion of such Holder’s or Holders’ Registrable Securities as are specified in such request, together with all or such portion of the Registrable Securities of any other Holder or Holders joining in such request as are specified in a written request given within ten (10) days after receipt of such written notice from the Company; provided, however, that the Company shall not be obligated to effect any such registration, qualification or compliance pursuant to this Section 2.4:

(i) if Form S-3 is not available for such offering by the Holders, or

(ii) if the Holders, together with the holders of any other securities of the Company entitled to inclusion in such registration, propose to sell Registrable Securities and such other securities (if any) at an aggregate price to the public of less than two million dollars ($2,000,000), or

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(iii) if within thirty (30) days of receipt of a written request from any Holder or Holders pursuant to this Section 2.4, the Company gives notice to such Holder or Holders of the Company’s intention to make a public offering within ninety (90) days, other than pursuant to a Special Registration Statement, or

(iv) if the Company shall furnish to the Holders a certificate signed by the Chairman of the Board of Directors of the Company stating that in the good faith judgment of the Board of Directors of the Company, it would be detrimental to the Company and its stockholders for such Form S-3 registration to be effected at such time, in which event the Company shall have the right to defer the filing of the Form S-3 registration statement for a period of not more than ninety (90) days after receipt of the request of the Holder or Holders under this Section 2.4; provided, that such right to delay a request shall be exercised by the Company not more than once in any twelve (12) month period, or

(v) in any particular jurisdiction in which the Company would be required to qualify to do business or to execute a general consent to service of process in effecting such registration, qualification or compliance.

(c) Subject to the foregoing, the Company shall file a Form S-3 registration statement covering the Registrable Securities and other securities so requested to be registered as soon as practicable after receipt of the requests of the Holders. Registrations effected pursuant to this Section 2.4 shall not be counted as demands for registration or registrations effected pursuant to Section 2.2.

2.5 Expenses of Registration. Except as specifically provided herein, all Registration Expenses incurred in connection with any registration, qualification or compliance pursuant to Section 2.2, 2.3 or 2.4 herein shall be borne by the Company. All Selling Expenses incurred in connection with any registrations hereunder, shall be borne by the holders of the securities so registered pro rata on the basis of the number of shares so registered. The Company shall not, however, be required to pay for expenses of any registration proceeding begun pursuant to Section 2.2 or 2.4, the request of which has been subsequently withdrawn by the Initiating Holders unless (a) the withdrawal is based upon material adverse information concerning the Company of which the Initiating Holders were not aware at the time of such request or (b) the Holders of a majority of Registrable Securities agree to deem such registration to have been effected as of the date of such withdrawal for purposes of determining whether the Company shall be obligated pursuant to Section 2.2(c) to undertake any subsequent registration, in which event such right shall be forfeited by all Holders. If the Holders are required to pay the Registration Expenses, such expenses shall be borne by the holders of securities (including Registrable Securities) requesting such registration in proportion to the number of shares for which registration was requested. If the Company is required to pay the Registration Expenses of a withdrawn offering pursuant to clause (a) above, then such registration shall not be deemed to have been effected for purposes of determining whether the Company shall be obligated pursuant to Section 2.2(c) to undertake any subsequent registration.

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2.6 Obligations of the Company. Whenever required to effect the registration of any Registrable Securities, the Company shall, as expeditiously as reasonably possible:

(a) prepare and file with the SEC a registration statement with respect to such Registrable Securities and use all reasonable efforts to cause such registration statement to become effective, and, upon the request of the Holders of a majority of the Registrable Securities registered thereunder, keep such registration statement effective for up to one hundred and twenty (120) days or, if earlier, until the distribution contemplated in the registration statement has been completed; provided however, that (i) such one hundred and twenty (120) day period shall be extended for a period of time equal to the period the Holder refrains from selling any securities included in such registration at the request of an underwriter of such Registrable Securities; and (ii) in the case of any registration of Registrable Shares on Form S-3 which are intended to be offered on a continuous or delayed basis, subject to compliance with applicable SEC rules, such one hundred and twenty (120) day period shall be extended for up to ninety (90) days, if necessary, to keep the registration statement effective until the earlier of when all such Registrable Shares are sold or when such Holders are eligible to sell such Registrable Securities pursuant to Rule 144 (or any similar rule then in effect); and before filing a registration statement or prospectus or any amendment or supplements thereto, furnish to the Holders and the underwriter or underwriters, if any, copies of all such documents proposed to be filed, including documents incorporated by reference in the prospectus, which are not yet publicly available and, if requested by the Holders, the exhibits incorporated by reference, which are not yet publicly available, and the Holders shall have the opportunity to object to any information pertaining to the Holders that is contained therein and the Company will make the corrections reasonably requested by the Holders with respect to such information prior to filing any registration statement or amendment thereto or any prospectus or any supplement thereto; provided, however, that at any time, upon written notice to the participating Holders and for a period not to exceed sixty (60) days thereafter (the “Suspension Period”), the Company may delay the filing or effectiveness of any registration statement or suspend the use or effectiveness of any registration statement (and the Initiating Holders hereby agree not to offer or sell any Registrable Securities pursuant to such registration statement during the Suspension Period) if the Company reasonably believes that there is or may be in existence material nonpublic information or events involving the Company, the failure of which to be disclosed in the prospectus included in the registration statement could result in a Violation (as defined below). In the event that the Company shall exercise its right to delay or suspend the filing or effectiveness of a registration hereunder, the applicable time period during which the registration statement is to remain effective shall be extended by a period of time equal to the duration of the Suspension Period. The Company may extend the Suspension Period for an additional consecutive sixty (60) days with the consent of the holders of a majority of the Registrable Securities registered under the applicable registration statement, which consent shall not be unreasonably withheld. No more than two (2) such Suspension Periods shall occur in any twelve (12) month period. If so directed by the Company, all Holders registering shares under such registration statement shall (i) not offer to sell any Registrable Securities pursuant to the registration statement during the period in which the delay or suspension is in effect after receiving notice of such delay or suspension; and (ii) use their reasonable best efforts to deliver to the Company (at the Company’s expense) all copies, other than permanent file copies then in such Holders’ possession, of the prospectus relating to such Registrable Securities current at the time of receipt of such notice. Notwithstanding the foregoing, the Company shall not be required to file, cause to become effective or maintain the effectiveness of any registration statement other than a registration statement on Form S-3 that contemplates a distribution of securities on a delayed or continuous basis pursuant to Rule 415 under the Securities Act;

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(b) prepare and file with the SEC such amendments and supplements to such registration statement and the prospectus used in connection with such registration statement as may be necessary to comply with the provisions of the Securities Act with respect to the disposition of all securities covered by such registration statement for the period set forth in subsection (a) above;

(c) furnish to the Holders such number of copies of a prospectus, including a preliminary prospectus, and all amendments and supplements thereto, in conformity with the requirements of the Securities Act, and such other documents as they may reasonably request in order to facilitate the disposition of Registrable Securities owned by them;

(d) use its best efforts to register and qualify the securities covered by such registration statement under such other securities or Blue Sky laws of such jurisdictions as shall be reasonably requested by the Holders; provided that the Company shall not be required in connection therewith or as a condition thereto to qualify to do business or to file a general consent to service of process in any such states or jurisdictions;

(e) in the event of any underwritten public offering, enter into and perform its obligations under an underwriting agreement, in usual and customary form, with the managing underwriter(s) of such offering and take all such other customary actions as the Holders or the managing underwriters of such offering reasonably request in order to expedite or facilitate the disposition of the securities covered by such registration statement (including, without limitation, making members of senior management of the Company available to participate in “road-show” and other customary marketing activities (including one-on-one meetings with prospective purchasers of the securities)). Each Holder participating in such underwriting shall also enter into and perform its obligations under such an agreement;

(f) notify each Holder of Registrable Securities covered by such registration statement and each underwriter and (if requested by any such person) confirm such notice in writing (i) when a prospectus or any prospectus supplement or post-effective amendment has been filed and, with respect to a registration statement or any post-effective amendment, when the same has become effective, (ii) of the issuance by any state securities or other regulatory authority of any order suspending the qualification or exemption from qualification of any of the Registrable Securities under state securities or Blue Sky laws or the initiation, or threatened initiation, of any proceedings for that purpose, or (iii) at any time when a prospectus relating thereto is required to be delivered under the Securities Act 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 misleading in the light of the circumstances then existing. The Company will use reasonable best efforts to amend or supplement such prospectus in order to cause such prospectus not to include any 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 the light of the circumstances then existing;

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(g) use its reasonable best efforts to furnish, on the date that such Registrable Securities are delivered to the underwriters for sale, if such securities are being sold through underwriters, (i) an opinion, dated as of such date, of the counsel representing the Company for the purposes of such registration, in form and substance as is customarily given to underwriters in an underwritten public offering, addressed to the underwriters, if any, and (ii) a letter, dated as of such date, from the independent certified public accountants of the Company, in form and substance as is customarily given by independent certified public accountants to underwriters in an underwritten public offering addressed to the underwriters and covering such matters of the type customarily covered by opinions or comfort letters, as the case may be, as the selling Holders, lead underwriters or managing underwriters reasonably request;

(h) to the extent not prohibited by applicable law or pre-existing applicable contractual restrictions, (i) make available, for inspection by the Holders, any underwriter participating in any disposition pursuant to such registration statement, and any attorney retained by any such underwriter, all financial and other records, pertinent corporate documents and properties of the Company, (ii) cause the Company’s officers and employees to supply all information reasonably requested by the Holders or such underwriter or attorney in connection with such registration statement, and (iii) make the Company’s independent accountants available for any such underwriter’s due diligence;

(i) cause all Registrable Securities to be listed on each securities exchange on which securities of the same class issued by the Company are then listed or, if no such similar securities are then listed, on Nasdaq or a national securities exchange selected by the Company;

(j) provide a transfer agent and registrar for all such Registrable Securities not later than the effective date of such registration statement;

(k) make generally available to its stockholders a consolidated earnings statement (which need not be audited) for the 12 months beginning after the effective date of such registration statement as soon as reasonably practicable after the end of such period, which earnings statement shall satisfy the requirements of an earning statement under Section 11(a) of the Securities Act;

(l) promptly respond to any and all comments received from the SEC, with a view towards causing the registration statement or any amendment thereto to be declared effective by the SEC as soon as reasonably practicable and shall file an acceleration request as soon as reasonably practicable following the resolution or clearance of all SEC comments or, if applicable, following notification by the SEC that any such registration statement or any amendment thereto will not be subject to review;

(m) at all times after the Company has filed a registration statement with the SEC pursuant to the requirements of the Securities Act, the Company shall use its commercially reasonable efforts to file all reports required to be filed by it under the Securities Act and the Exchange Act and the rules and regulations adopted by the SEC thereunder, and use its commercially reasonable efforts to take such further action as the Holders may reasonably request, all to the extent required to enable the Holders to be eligible to sell Registrable Securities pursuant to Rule 144 (or any similar rule then in effect);

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(n) promptly notify the Holders and the underwriter or underwriters, if any:

(i) when the registration statement, any pre-effective amendment, the prospectus or any prospectus supplement or post-effective amendment to the registration statement has been filed and, with respect to the registration statement or any post-effective amendment, when the same has become effective;

(ii) of the notification to the Company by the SEC of its initiation of any proceeding with respect to the issuance by the SEC of any stop order suspending the effectiveness of the registration statement; and

(iii) of the receipt by the Company of any notification with respect to the suspension of the qualification of any Registrable Securities for sale under the applicable securities or blue sky laws of any jurisdiction;

(o) make such representations and warranties to the selling Holders of Registrable Securities and the underwriters as are customarily made by issuers to selling stockholders and underwriters, as the case may be, in primary underwritten public offerings;

(p) use reasonable best efforts to prevent the issuance of any stop order suspending the effectiveness of such registration statement or of any order preventing or suspending the use of any preliminary prospectus and, if any such order is issued, to obtain the lifting thereof at the earliest reasonable time; and

(q) otherwise use its best efforts to comply with all applicable rules and regulations of the SEC.

2.7 Delay of Registration; Furnishing Information.

(a) It shall be a condition precedent to the obligations of the Company to take any action pursuant to Section 2.2, 2.3 or 2.4 that the selling Holders shall furnish to the Company such information regarding themselves, the Registrable Securities held by them and the intended method of disposition of such securities as shall be required to effect the registration of their Registrable Securities.

(b) The Company shall have no obligation with respect to any registration requested pursuant to Section 2.2 or Section 2.4 if the number of shares or the anticipated aggregate offering price of the Registrable Securities to be included in the registration does not equal or exceed the number of shares or the anticipated aggregate offering price required to originally trigger the Company’s obligation to initiate such registration as specified in Section 2.2 or Section 2.4, whichever is applicable.

2.8 Indemnification. In the event any Registrable Securities are included in a registration statement under Sections 2.2, 2.3 or 2.4:

(a) To the extent permitted by law, the Company will indemnify and hold harmless each Holder, the partners, members, employees, officers, stockholders and directors of each Holder, any underwriter (as defined in the Securities Act) for such Holder and each person,

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if any, who controls such Holder or underwriter within the meaning of the Securities Act or the Exchange Act, against any losses, claims, damages, or liabilities (joint or several) to which they may become subject under the Securities Act, the Exchange Act or other federal or state law, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any of the following statements, omissions or violations (collectively a “Violation”) by the Company: (i) any untrue statement or alleged untrue statement of a material fact contained in such registration statement or incorporated by reference therein, including any preliminary prospectus or final prospectus contained therein or any amendments or supplements thereto, (ii) 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, (iii) any breach of this Agreement, or (iv) any violation or alleged violation by the Company of the Securities Act, the Exchange Act, any state securities law or any rule or regulation promulgated under the Securities Act, the Exchange Act or any state securities law in connection with the offering covered by such registration statement; and the Company will reimburse each such Holder, partner, member, employee, officer, stockholder, director, underwriter or controlling person for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action; provided however, that the indemnity agreement contained in this Section 2.8(a) shall not apply to amounts paid in settlement of any such loss, claim, damage, liability or action if such settlement is effected without the consent of the Company, which consent shall not be unreasonably withheld, nor shall the Company be liable in any such case for any such loss, claim, damage, liability or action to the extent that it arises out of or is based upon a Violation which occurs in reliance upon and in conformity with written information furnished to the Company (such written information strictly limited to the name and address of such Holder and the number of Registrable Securities included in the registration statement by such Holder) expressly for use in connection with such registration by such Holder, partner, member, employee, officer, stockholder, director, underwriter or controlling person of such Holder.

(b) To the extent permitted by law, each Holder will, if Registrable Securities held by such Holder are included in the securities as to which such registration qualifications or compliance is being effected, severally and not jointly, indemnify and hold harmless the Company, each of its directors, its officers and each person, if any, who controls the Company within the meaning of the Securities Act, any underwriter and any other Holder selling securities under such registration statement or any of such other Holder’s partners, directors or officers or any person who controls such Holder, against any losses, claims, damages or liabilities (joint or several) to which the Company or any such director, employee, officer, controlling person, underwriter or other such Holder, or partner, director, officer or controlling person of such other Holder may become subject under the Securities Act, the Exchange Act or other federal or state law, insofar as such losses, claims, damages or liabilities (or actions in respect thereto) arise out of or are based upon any of the following statements: (i) any untrue statement or alleged untrue statement of a material fact contained in such registration statement or incorporated by reference therein, including any preliminary prospectus or final prospectus contained therein or any amendments or supplements thereto, (ii) 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 (iii) any violation or alleged violation by the Company of the Securities Act (collectively, a “Holder Violation”), in each case to the extent (and only to the extent) that such Holder Violation occurs in reliance upon and in conformity with written information furnished to the Company by such Holder (such written information strictly limited to the name and address of such Holder and the number of Registrable Securities included in the registration statement by such Holder) under an instrument duly executed by such Holder and stated to be specifically for use in connection with such registration;

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and each such Holder will reimburse any legal or other expenses reasonably incurred by the Company or any such director, employee, officer, controlling person, underwriter or other Holder, or partner, officer, director or controlling person of such other Holder in connection with investigating or defending any such loss, claim, damage, liability or action if it is judicially determined that there was such a Holder Violation; provided, however, that the indemnity agreement contained in this Section 2.8(b) shall not apply to amounts paid in settlement of any such loss, claim, damage, liability or action if such settlement is effected without the consent of the Holder, which consent shall not be unreasonably withheld; provided further, that in no event shall any indemnity under this Section 2.8 exceed the net proceeds from the offering received by such Holder.

(c) Promptly after receipt by an indemnified party under this Section 2.8 of notice of the commencement of any action (including any governmental action), such indemnified party will, if a claim in respect thereof is to be made against any indemnifying party under this Section 2.8, deliver to the indemnifying party a written notice of the commencement thereof and the indemnifying party shall have the right to participate in, and, to the extent the indemnifying party so desires, jointly with any other indemnifying party similarly noticed, to assume the defense thereof with counsel mutually satisfactory to the parties; provided, however, that an indemnified party shall have the right to retain its own counsel, with the fees and expenses thereof to be paid by the indemnified party if representation of such indemnified party by the counsel retained by the indemnifying party would be inappropriate due to actual or potential differing interests between such indemnified party and any other party represented by such counsel in such proceeding, by the indemnifying party. The failure to deliver written notice to the indemnifying party within a reasonable time of the commencement of any such action shall relieve such indemnifying party of any liability to the indemnified party under this Section 2.8 to the extent, and only to the extent, prejudicial to its ability to defend such action, but the omission so to deliver written notice to the indemnifying party will not relieve it of any liability that it may have to any indemnified party otherwise than under this Section 2.8.

(d) If the indemnification provided for in this Section 2.8 is required by its terms but is for any reason held by a court of competent jurisdiction to be unavailable to or otherwise insufficient to an indemnified party with respect to any losses, claims, damages or liabilities referred to herein, then each applicable indemnifying party, in lieu of indemnifying such indemnified party thereunder, shall to the extent permitted by applicable law contribute to the amount paid or payable by such indemnified party as a result of such loss, claim, damage or liability 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 Violation(s) or Holder Violation(s) that resulted in such loss, claim, damage or liability, as well as any other relevant equitable considerations. The relative fault of the indemnifying party and of the indemnified party shall be determined by a court of law by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission to state a material fact relates to information supplied by the indemnifying party or by the indemnified party and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission; provided, that in no event shall any contribution by a Holder hereunder exceed the net proceeds from the offering received by such Holder.

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(e) The obligations of the Company and Holders under this Section 2.8 shall survive completion of any offering of Registrable Securities in a registration statement and, with respect to liability arising from an offering to which this Section 2.8 would apply that is covered by a registration filed before termination of this Agreement, such termination. 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.

2.9 Assignment of Registration Rights. The rights to cause the Company to register Registrable Securities pursuant to this Section 2 may be assigned by a Holder to a transferee or assignee of Registrable Securities (for so long as such shares remain Registrable Securities) that (a) is a subsidiary, parent, general partner, limited partner, retired partner, member or retired member, of a Holder that is a corporation, partnership or limited liability company, (b) is a Holder’s family member or trust for the benefit of an individual Holder, (c) is a transferee satisfying the criteria to be a Major Investor, (d) is an entity affiliated by common control (or other related entity) with such Holder, or (e) is an entity having direct investment authority over such Holder; provided, however, (i) the transferor shall, within ten (10) days after such transfer, furnish to the Company written notice of the name and address of such transferee or assignee and the securities with respect to which such registration rights are being assigned and (ii) such transferee shall agree to be subject to all restrictions set forth in this Agreement.

2.10 Limitation on Subsequent Registration Rights. Other than as provided in Section 5.10, after the date of this Agreement, the Company shall not enter into any agreement with any holder or prospective holder of any securities of the Company that would grant such holder rights to demand the registration of shares of the Company’s capital stock, or to include such shares in a registration statement that would reduce the number of shares includable by the Holders.

2.11 “Market Stand-Off” Agreement. Each Holder hereby agrees that such Holder shall not sell, transfer, make any short sale of, grant any option for the purchase of, or enter into any hedging or similar transaction with the same economic effect as a sale, any Common Stock (or other securities) of the Company held by such Holder (other than those included in the registration) (i) during the 180-day period following the effective date of the Initial Offering (or such longer period, not to exceed eighteen (18) days after the expiration of the 180-day period, as the underwriters or the Company shall request in order to facilitate compliance with FINRA Rule 2711), and (ii) the 90-day period following the effective date of a registration statement of the Company filed under the Securities Act (or such longer period, not to exceed eighteen (18)days after the expiration of the 90-day period, as the underwriters or the Company shall request in order to facilitate compliance with FINRA Rule 2711); provided, that, with respect to (i) and (ii) above, all officers and directors of the Company and holders of at least one percent (1%) of the Company’s voting securities are bound by and have entered into similar agreements. The obligations described in this Section 2.11 shall not apply to a registration relating solely to employee benefit plans on Form S-1 or Form S-8 or similar forms that may be promulgated in the future, or a registration relating solely to a transaction on Form S-4 or similar forms that may be promulgated in the future.

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2.12 Agreement to Furnish Information. Each Holder agrees to execute and deliver such other agreements as may be reasonably requested by the Company or the underwriter that are consistent with the Holder’s obligations under Section 2.11 or that are necessary to give further effect thereto. In addition, if requested by the Company or the representative of the underwriters of Common Stock (or other securities) of the Company, each Holder shall provide, within ten (10) days of such request, such information as may be required by the Company or such representative in connection with the completion of any public offering of the Company’s securities pursuant to a registration statement filed under the Securities Act. The obligations described in Section 2.11 and this Section 2.12 shall not apply to a Special Registration Statement. The Company may impose stop-transfer instructions with respect to the shares of Common Stock (or other securities) subject to the foregoing restriction until the end of said day period. Each Holder agrees that any transferee of any shares of Registrable Securities shall be bound by Sections 2.11 and 2.12. The underwriters of the Company’s stock are intended third party beneficiaries of Sections 2.11 and 2.12 and shall have the right, power and authority to enforce the provisions hereof as though they were a party hereto.

2.13 Rule 144 Reporting. With a view to making available to the Holders the benefits of certain rules and regulations of the SEC 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 SEC Rule 144 or any similar or analogous rule promulgated under the Securities Act, at all times after the effective date of the Initial Offering;

(b) file with the SEC, in a timely manner, all reports and other documents required of the Company under the Exchange Act (at any time after it has become subject to such reporting requirements) and take such further action as the Holders may reasonably request, all to the extent required from time to time to enable the Holders to sell securities of the Company without registration; and

(c) so long as a Holder owns any Registrable Securities, furnish to such Holder forthwith upon request: a written statement by the Company as to its compliance with the reporting requirements of said Rule 144 of the Securities Act, and of the Exchange Act (at any time after it has become subject to such reporting requirements); a copy of the most recent annual or quarterly report of the Company filed with the Commission; and such other reports and documents as a Holder may reasonably request in connection with availing itself of any rule or regulation of the SEC allowing it to sell any such securities without registration.

2.14 Termination of Registration Rights. The right of any Holder to request registration or inclusion of Registrable Securities in any registration pursuant to Section 2.2, Section 2.3, or Section 2.4 shall terminate upon the earlier of: (i) the date three (3) years following an initial public offering that results in the conversion of all outstanding Shares; or (ii) such time as the Company has completed its Initial Offering and all Registrable Securities of the Company issuable or issued upon conversion of the Shares held by and issuable to such Holder (and its affiliates) may be sold pursuant to Rule 144 during any ninety (90) day period. Upon such termination, such shares shall cease to be “Registrable Securities” hereunder for all purposes.

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SECTION 3. COVENANTS.

3.1 Basic Financial Information and Reporting.

(a) The Company will maintain true books and records of account in which full and correct entries will be made of all its business transactions pursuant to a system of accounting established and administered in accordance with generally accepted accounting principles consistently applied (except as noted therein or as disclosed to the recipients thereof), and will set aside on its books all such proper accruals and reserves as shall be required under generally accepted accounting principles consistently applied.

(b) As soon as practicable after the end of each fiscal year of the Company, and in any event within ninety (90) days thereafter, the Company will furnish each Major Investor (and Amgen Inc., for so long as Amgen continues to hold at least 600,000 shares (as adjusted for stock splits, dividends, recapitalizations and the like following the C-1 Closing) of Series A Preferred) a balance sheet of the Company, as at the end of such fiscal year, and a statement of income and a statement of cash flows of the Company, for such year, all prepared in accordance with generally accepted accounting principles consistently applied (except as noted therein or as disclosed to the recipients thereof) and setting forth in each case in comparative form the figures for the previous fiscal year, all in reasonable detail. Such financial statements shall be accompanied by a report and opinion thereon by independent public accountants selected by the Company’s Board of Directors.

(c) The Company will furnish each Major Investor (and Amgen Inc. for so long as Amgen continues to hold at least 600,000 shares (as adjusted for stock splits, dividends, recapitalizations and the like following the C-1 Closing) of Series A Preferred), as soon as practicable after the end of the first, second and third quarterly accounting periods in each fiscal year of the Company, and in any event within forty-five (45) days thereafter, a balance sheet of the Company as of the end of each such quarterly period, and a statement of income and a statement of cash flows of the Company for such period and for the current fiscal year to date, prepared in accordance with generally accepted accounting principles consistently applied (except as noted therein or as disclosed to the recipients thereof), with the exception that no notes need be attached to such statements and year-end audit adjustments may not have been made.

(d) So long as any Investor qualifies as a Major Investor, the Company will furnish each such Major Investor (and Amgen Inc. for so long as Amgen continues to hold at least 600,000 shares (as adjusted for stock splits, dividends, recapitalizations and the like following the C-1 Closing) of Series A Preferred): (i) at least thirty (30) days prior to the beginning of each fiscal year an annual budget and operating plans for such fiscal year (and as soon as available, any subsequent written revisions thereto); and (ii) as soon as practicable after the end of each month, and in any event within twenty (20) days thereafter, a balance sheet of the Company as of the end of each such month, and a statement of income and a statement of cash flows of the Company for such month and for the current fiscal year to date, including a comparison to plan figures for such period, prepared in accordance with generally accepted

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accounting principles consistently applied (except as noted thereon), with the exception that no notes need be attached to such statements and year-end audit adjustments may not have been made.

3.2 Inspection Rights. Each Major Investor shall have the right to visit and inspect any of the properties of the Company or any of its subsidiaries, and to discuss the affairs, finances and accounts of the Company or any of its subsidiaries with its officers, and to review such information as is reasonably requested all at such reasonable times and as often as may be reasonably requested; provided, however, that the Company shall not be obligated under this Section 3.2 with respect to a competitor of the Company or with respect to information which the Board of Directors determines in good faith that provision of such information to such Major Investor would result in significant competitive harm to the Company and should not, therefore, be disclosed. For the avoidance of doubt, Amgen Inc. and its affiliates shall not be considered competitors of the Company for the purposes of this Section.

3.3 Confidentiality of Records. Each Investor agrees to use the same degree of care as such Investor uses to protect its own confidential information to keep confidential any information furnished to such Investor pursuant to Section 3.1 and Section 3.2 that the Company identifies as being confidential or proprietary (so long as such information is not in the public domain), except that such Investor may disclose such proprietary or confidential information (i) to any partner, subsidiary or parent of such Investor as long as such partner, subsidiary or parent is advised of and agrees or has agreed to be bound by the confidentiality provisions of this Section 3.3 or comparable restrictions; (ii) at such time as it enters the public domain through no fault of such Investor; (iii) that is communicated to it free of any obligation of confidentiality; (iv) that is developed by Investor or its agents independently of and without reference to any confidential information communicated by the Company; or (v) as required by applicable law.

3.4 Reservation of Common Stock. The Company will at all times reserve and keep available, solely for issuance and delivery upon the conversion of the Preferred Stock, all Common Stock issuable from time to time upon such conversion.

3.5 Amendment to Plan. Concurrently with or promptly following the C-2 Closing, the Company and each Investor shall take such actions as are necessary to increase the available option pool under the Company’s Amended and Restated 2007 Equity Incentive Plan to equal approximately ten and one-quarter percent (10.25%) of the Company’s fully diluted capitalization after giving effect to the issuance and sale of Series C Preferred and the warrants exercisable for Series C Preferred pursuant to the Purchase Agreement.

3.6 Other Covenants.

(a) The Company and the Investors shall take all actions necessary to amend the Restated Charter following the Subsequent C-1 Closing to reduce the authorized number of shares of:

(i) Series A to equal the number of shares of Series A outstanding immediately following the Subsequent C-1 Closing;

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(ii) Series A-1 to equal the number of shares of Series A-1 outstanding immediately following the Subsequent C-1 Closing;

(iii) Series B-1 to equal the number of shares of Series B-1 outstanding immediately following the Subsequent C-1 Closing;

(iv) Series B-2 to equal the number of shares of Series B-2 outstanding plus the number of shares of Series B-1 issuable in accordance with warrants outstanding immediately following the Subsequent C-1 Closing; and

(v) Common Stock to equal the number of shares of Common Stock outstanding plus the number of shares of Common Stock required to be reserved for issuance upon conversion or exercise, as applicable, of all of the shares of Series Preferred, warrants therefore and options outstanding, issuable, or available for grant after giving effect to the C-2 Closing in accordance with the Purchase Agreement.

(b) The Company and the Investors shall take all actions necessary to amend the Restated Charter following the C-2 Closing to reduce the authorized number of shares of:

(i) Series A to equal the number of shares of Series A outstanding immediately following the C-2 Closing;

(ii) Series A-1 to equal the number of shares of Series A-1 outstanding immediately following the C-2 Closing;

(iii) Series B-1 to equal the number of shares of Series B-1 outstanding immediately following the C-2 Closing; and

(iv) Series B-2 to equal the number of shares of Series B-2 outstanding plus the number of shares of Series B-1 issuable in accordance with warrants outstanding immediately following the C-2 Closing;

(v) Series C-1 to equal the number of shares of Series C-1 outstanding plus the number of shares of Series C-1 issuable in accordance with warrants outstanding immediately following the C-2 Closing;

(vi) Series C-2 to equal the number of shares of Series C-2 outstanding plus the number of shares of Series C-2 issuable in accordance with warrants outstanding immediately following the C-2 Closing; and

(vii) Series C to equal the number of shares of Series C outstanding immediately following the C-2 Closing.

3.7 Termination of Covenants. All covenants of the Company contained in Section 3 (other than the provisions of Section 3.4) shall expire and terminate as to each Investor upon the earlier of (i) the effective date of the registration statement pertaining to an Initial Offering or (ii) upon the consummation of an “Acquisition” or an “Asset Transfer”, as each as defined in and approved in accordance with the terms of the Restated Charter.

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SECTION 4. RIGHTS OF FIRST REFUSAL.

4.1 Subsequent Offerings. Subject to applicable securities laws, each Major Investor shall have a right of first refusal to purchase its pro rata share of all Equity Securities, as defined below, that the Company may, from time to time, propose to sell and issue after the date of this Agreement, other than the Equity Securities excluded by Section 4.7. Each Investor’s pro rata share is equal to the ratio of (a) the number of shares of the Company’s Common Stock (including all shares of Common Stock issuable or issued upon conversion of the Shares or upon the exercise of outstanding warrants or options) of which such Investor is deemed to be a holder immediately prior to the issuance of such Equity Securities to (b) the total number of shares of the Company’s outstanding Common Stock (including all shares of Common Stock issued or issuable upon conversion of the Shares or upon the exercise of any outstanding warrants or options) immediately prior to the issuance of the Equity Securities. The term “Equity Securities” shall mean (i) any Common Stock, Preferred Stock or other security of the Company, (ii) any security convertible into or exercisable or exchangeable for, with or without consideration, any Common Stock, Preferred Stock or other security (including any option to purchase such a convertible security), (iii) any security carrying any warrant or right to subscribe to or purchase any Common Stock, Preferred Stock or other security or (iv) any such warrant or right.

4.2 Exercise of Rights. If the Company proposes to issue any Equity Securities, it shall give each Major Investor written notice of its intention, describing the Equity Securities, the price and the terms and conditions upon which the Company proposes to issue the same. Each Major Investor shall have fifteen (15) days from the giving of such notice to agree to purchase its pro rata share of the Equity Securities for the price and upon the terms and conditions specified in the notice by giving written notice to the Company and stating therein the quantity of Equity Securities to be purchased. Notwithstanding the foregoing, the Company shall not be required to offer or sell such Equity Securities to any Major Investor who would cause the Company to be in violation of applicable federal securities laws by virtue of such offer or sale.

4.3 Issuance of Equity Securities to Other Persons. If not all of the Major Investors elect to purchase their pro rata share of the Equity Securities, then the Company shall promptly notify in writing the Major Investors who do so elect and shall offer such Major Investors the right to acquire such unsubscribed shares on a pro rata basis. The Major Investors shall have ten (10) days after receipt of such notice to notify the Company of its election to purchase all or a portion thereof of the unsubscribed shares. The Company shall have ninety (90) days thereafter to sell the Equity Securities in respect of which the Major Investor’s rights were not exercised, at a price and upon general terms and conditions not materially more favorable to the purchasers thereof than specified in the Company’s notice to the Major Investors pursuant to Section 4.2. If the Company has not sold such Equity Securities within ninety (90) days of the notice provided pursuant to Section 4.2, the Company shall not thereafter issue or sell any Equity Securities, without first offering such securities to the Major Investors in the manner provided above.

4.4 Sale Without Notice. In lieu of giving notice to the Major Investors prior to the issuance of Equity Securities as provided in Section 4.2, the Company may elect to give notice to the Major Investors within thirty (30) days after the issuance of Equity Securities. Such notice shall describe the type, price and terms of the Equity Securities.

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Each Major Investor shall have twenty (20) days from the date of receipt of such notice to elect to purchase up to the number of shares that would, if purchased by such Major Investor, maintain such Major Investor’s pro rata share (as set forth in Section 4.1) of the Company’s equity securities after giving effect to all such purchases. The closing of such sale shall occur within sixty (60) days of the date of notice to the Major Investors.

4.5 Termination and Waiver of Rights of First Refusal. The rights of first refusal established by this Section 4 shall not apply to, and shall terminate upon the earlier of (i) the effective date of the registration statement pertaining to the Company’s Initial Offering, (ii) an Asset Transfer approved in accordance with the terms of the Restated Charter or (iii) an Acquisition approved in accordance with the terms of the Restated Charter. Notwithstanding Section 5.5, the rights of first refusal established by this Section 4 may be amended, or any provision waived with and only with the written consent of the Company and the Major Investors holding a majority of the Registrable Securities held by all Major Investors, or as permitted by Section 5.5.

4.6 Assignment of Rights of First Refusal. The rights of first refusal of each Major Investor under this Section 4 may be assigned to the same parties, subject to the same restrictions as any transfer of registration rights pursuant to Section 2.9.

4.7 Excluded Securities. The rights of first refusal established by this Section 4 shall have no application to any Equity Securities that are excluded from the definition of “Additional Shares of Common Stock” as defined in the Company’s Restated Charter.

SECTION 5. MISCELLANEOUS.

5.1 Governing Law. This Agreement shall be governed by and construed under the laws of the State of Delaware, without reference to conflicts of laws or principles thereof. The parties agree that any action brought by either party under or in relation to this Agreement, including without limitation to interpret or enforce any provision of this Agreement, shall be brought in, and each party agrees to and does hereby submit to the jurisdiction and venue of, any state or federal court located in the County of Santa Clara, California.

5.2 Successors and Assigns. Except as otherwise expressly provided herein, the provisions hereof shall inure to the benefit of, and be binding upon, the parties hereto and their respective successors, assigns, heirs, executors, and administrators and shall inure to the benefit of and be enforceable by each person who shall be a holder of Registrable Securities from time to time; provided, however, that prior to the receipt by the Company of adequate written notice of the transfer of any Registrable Securities specifying the full name and address of the transferee, the Company may deem and treat the person listed as the holder of such shares in its records as the absolute owner and holder of such shares for all purposes, including the payment of dividends or any redemption price.

5.3 Entire Agreement. This Agreement, the Exhibits and Schedules hereto, the Purchase Agreement and the other documents delivered pursuant thereto constitute the full and entire understanding and agreement between the parties with regard to the subjects hereof and no party shall be liable or bound to any other in any manner by any oral or written representations, warranties, covenants and agreements except as specifically set forth herein and therein. Each party expressly represents and warrants that it is not relying on any oral or written representations, warranties, covenants or agreements outside of this Agreement.

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5.4 Severability. In the event one or more of the provisions of this Agreement should, for any reason, be held to be invalid, illegal or unenforceable in any respect, such invalidity, illegality, or unenforceability shall not affect any other provisions of this Agreement, and this Agreement shall be construed as if such invalid, illegal or unenforceable provision had never been contained herein.

5.5 Amendment and Waiver.

(a) Except as otherwise expressly provided, this Agreement may be amended or modified, and the obligations of the Company and the rights of the Holders under this Agreement may be waived, only upon the written consent of the Company and the Requisite Holders.

(b) For the purposes of determining the number of Holders or Investors entitled to vote or exercise any rights hereunder, the Company shall be entitled to rely solely on the list of record holders of its stock as maintained by or on behalf of the Company.

(c) Notwithstanding anything in this Section 5.5 to the contrary, any written instrument effecting an amendment, waiver, discharge or termination of this Agreement that would (i) affect the rights of an Investor hereunder adversely and in a manner different from the other Investors, or (ii) impose any obligation to provide additional financing to the Company, shall be effective with respect to an Investor only if it is signed by such Investor. In addition, to the extent that any change to any ownership threshold specified in this Agreement relating to any rights of any Investor under this Agreement, or any new threshold relating to any rights of any Investor under this Agreement is imposed, which causes an Investor to lose such rights, then such change shall not be effective with respect to such Investor unless the written instrument effecting such change is signed by such Investor.

5.6 Delays or Omissions. It is agreed that no delay or omission to exercise any right, power, or remedy accruing to any party, upon any breach, default or noncompliance by another party under this Agreement shall impair any such right, power, or remedy, nor shall it be construed to be a waiver of any such breach, default or noncompliance, or any acquiescence therein, or of any similar breach, default or noncompliance thereafter occurring. It is further agreed that any waiver, permit, consent, or approval of any kind or character on any party’s part of any breach, default or noncompliance under the Agreement or any waiver on such party’s part of any provisions or conditions of this Agreement must be in writing and shall be effective only to the extent specifically set forth in such writing. All remedies, either under this Agreement, by law, or otherwise afforded to any party, shall be cumulative and not alternative.

5.7 Notices. All notices required or permitted hereunder shall be in writing and shall be deemed effectively given: (a) upon personal delivery to the party to be notified, (b) when sent by confirmed electronic mail (if such party accepts notice via electronic mail) or facsimile if sent during normal business hours of the recipient; if not, then on the next business day, (c) five (5) days after having been sent by registered or certified mail, return receipt requested, postage prepaid, or (d) one (1) day after deposit with a nationally recognized overnight courier, specifying next day delivery, with written verification of receipt.

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All communications shall be sent to the party to be notified at the address as set forth on the signature pages hereof or EXHIBIT A hereto or at such other address or electronic mail address (if such party accepts notice via electronic mail) as such party may designate by ten (10) days advance written notice to the other parties hereto.

5.8 Expenses. Except as otherwise provided for herein or otherwise agreed to in writing by the parties, all costs and expenses incurred in connection with the preparation of this Agreement shall be paid by the Company.

5.9 Titles and Subtitles. The titles of the sections and subsections of this Agreement are for convenience of reference only and are not to be considered in construing this Agreement.

5.10 Additional Investors. Notwithstanding anything to the contrary contained herein, if the Company shall issue additional shares of its Preferred Stock pursuant to the Purchase Agreement, the Company shall cause any purchaser of such shares of Preferred Stock to become a party to this Agreement by executing and delivering an additional counterpart signature page to this Agreement and shall be deemed an “Investor,” a “Holder” and a party hereunder. Notwithstanding anything to the contrary contained herein, if the Company shall issue Equity Securities described in subsections (D), (E) or (G) of Article IV, Section (E)(5)(h)(v) of the Restated Charter, any purchaser of such Equity Securities may become a party to this Agreement by executing and delivering an additional counterpart signature page to this Agreement and shall be deemed an “Investor,” a “Holder” and a party hereunder.

5.11 Waiver of Jury Trial. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY WAIVES ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATED TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY.

5.12 Equitable Relief. The parties hereto agree that legal remedies may be inadequate to enforce the provisions of this Agreement and that equitable relief, including specific performance and injunctive relief, may be used to enforce the provisions of this Agreement. If any party hereto or his heirs, personal representatives, or assigns institutes any action or proceeding to specifically enforce the provisions hereof, any person against whom such action or proceeding is brought hereby waives the claim or defense therein that such party or such personal representative has an adequate remedy at law, and such person shall not offer in any such action or proceeding the claim or defense that such remedy at law exists.

5.13 Counterparts. This Agreement may be executed in any number of counterparts, each of which shall be an original, but all of which together shall constitute one instrument.

5.14 Aggregation of Stock. All shares of Registrable Securities held or acquired by affiliated entities or persons or persons or entities under common management or control shall be aggregated together for the purpose of determining the availability of any rights under this Agreement.

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5.15 Pronouns. All pronouns contained herein, and any variations thereof, shall be deemed to refer to the masculine, feminine or neutral, singular or plural, as to the identity of the parties hereto may require.

5.16 Termination. Except with respect to Section 3.4, this Agreement shall terminate and be of no further force or effect upon the earlier of (i) an Acquisition or Asset Transfer approved in accordance with the Restated Charter; or (ii) the date three (3) years following the Closing of the Initial Offering.

[THIS SPACE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

COMPANY:
RELYPSA, INC.
By:	/s/ Gerrit Klaerner, Ph.D.
	Gerrit Klaerner, Ph.D.
	President and Chief Operating Officer

Address:	5301 Patrick Henry Drive
	Santa Clara, CA 95054

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:
ORBIMED PRIVATE INVESTMENTS IV, LP
By:	OrbiMed Capital GP IV LLC
Its:	General Partner
By:	/s/ Jonathan Silverstein
	Jonathan Silverstein
	General Partner

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:
NEW LEAF VENTURES I, L.P.
By:	New Leaf Venture Management I, L.P.
Its:	General Partner
By:	New Leaf Venture Management I, L.L.C.
Its:	General Partner
By:	/s/ Vijay Lathi
	Vijay Lathi
	Managing Director
SPROUT CAPITAL IX, L.P.
By:	DLJ Capital Corporation
Its:	Managing General Partner
By:	/s/ Vijay Lathi
	Vijay Lathi
	Attorney in Fact
SPROUT ENTREPRENEURS FUND, L.P.
By:	DLJ Capital Corporation
Its:	General Partner
By:	/s/ Vijay Lathi
	Vijay Lathi
	Attorney in Fact

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:
5AM VENTURES II, LP by its General Partner
5AM CO-INVESTORS II, LP, by its General Partner
5AM Partners II LLC
By:	/s/ Scott Rocklage
	Scott Rocklage
	Managing Member
5AM VENTURES III, LP by its General Partner
5AM CO-INVESTORS III, LP, by its General Partner
5AM Partners III LLC
By:	/s/ Scott Rocklage
	Scott Rocklage
	Managing Member

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

DELPHI VENTURES VII, L.P.
By:	Delphi Management Partners VII, LLC
	General Partner
By:	/s/ James J. Bochnowski
	James J. Bochnowski
	Managing Member
DELPHI BIOINVESTMENTS VII, L.P.
By:	Delphi Management Partners VII, LLC
	General Partner
By:	/s/ James J. Bochnowski
	James J. Bochnowski
	Managing Member

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:
MEDIPHASE VENTURE PARTNERS II LIMITED PARTNERSHIP
By:	Mediphase II LLC
Its:	General Partner
By:	/s/ Paul A Howard
	Paul A. Howard
	Manager
MEDIPHASE VENTURE PARTNERS (DP & UP) LIMITED PARTNERSHIP
By:	Mediphase (DP & UP) LLC
Its:	General Partner
By:	/s/ Paul A. Howard
	Paul A. Howard
	Manager
MEDIPHASE VENTURE PARTNERS II (SELECT FUND) LIMITED PARTNERSHIP
By:	Mediphase II (Select Fund) LLC
Its:	General Partner
By:	/s/ Paul A. Howard
	Paul A. Howard
	Manager

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:
SIBLING CAPITAL FUND I, LLC
By:	Sibling Capital LLC
Its:	Manager
By:	/s/ Sandra I. Coufal, M.D.
	Sandra I. Coufal, M.D.
	President

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:
TRIPLEPOINT VENTURES LLC
By:	/s/ Sajal Srivastava
	Sajal Srivastava, Chief Operating Officer
TRIPLEPOINT CAPITAL LLC
By:	/s/ Sajal Srivastava
	Sajal Srivastava, Chief Operating Officer

IN WITNESS WHEREOF, the parties hereto have executed this SECOND AMENDED AND RESTATED INVESTOR RIGHTS AGREEMENT as of the date set forth in the first paragraph hereof.

INVESTORS:

SILICON VALLEY BANK

Signature:

Print Name:

Title:

SCHEDULE OF INVESTORS

NAME AND ADDRESS	NAME AND ADDRESS
OrbiMed Private Investments IV, LP c/o OrbiMed Advisors, LLC 601 Lexington Avenue, 54th Floor New York, NY 10022 Attn : Jonathan Silverstein and David Bonita	Delphi Ventures VII, L.P. Delphi BioInvestments VII, L.P. 3000 Sand Hill Road Building 1, Suite 135 Menlo Park, CA 94025 Attn: Deepa Pakianathan, Ph.D.
5AM Ventures II, LP 5AM Co-Investors II, LP 5AM Ventures III, LP 5AM Co-Investors III, LP 2200 Sand Hill Road Suite 110 Menlo Park, CA 94025 Attn: Scott M. Rocklage, Ph.D.	TriplePoint Ventures, LLC 2755 Sand Hill Road, Suite 150 Menlo Park, CA 94025 Attn: Sajal Srivastava, COO
New Leaf Ventures I, L.P. Sprout Capital IX, L.P. Sprout Entrepreneurs Fund, L.P. 2500 Sand Hill Road, Suite 203 Menlo Park, CA 94025 Attn: Ron Hunt and Vijay Lathi	Mediphase Venture Partners II Limited Partnership Mediphase Venture Partners II (Select Fund) Limited Partnership Mediphase Venture Partners (DP & UP) Limited Partnership 3 Newton Executive Park 2223 Washington Street, Suite 102 Newton, MA 02462 Attn: Paul Howard

Amgen Inc. One Amgen Center Drive Thousand Oaks, CA 91320-1799 Attn: Janis Naeve and Michael Mayes	Silicon Valley Bank 2400 Hanover Street Palo Alto, California 94304 Attn: Jason Hughes
Sibling Capital Fund I, LLC c/o Sibling Capital LLC BioInnovation Center 1441 Canal Street, Suite 422 New Orleans, LA 70112 Attn: Sandra I. Coufal, M.D.,