8-K

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D. C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date Of Report (Date of Earliest Event Reported) September 23, 2009

ATP OIL & GAS CORPORATION

(Exact name of registrant as specified in its charter)

Texas	001-32647	76-0362774
(State or other jurisdiction of incorporation)	(Commission file number)	(I.R.S. Employer Identification No.)

4600 Post Oak Place, Suite 200

Houston, Texas 77027

(Address of principal executive offices)

(Zip Code)

(713) 622-3311

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

¨ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

¨ Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

¨ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

¨ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 1.01. Entry into Material Definitive Agreement.

Underwriting Agreement

On September 23, 2009, ATP Oil & Gas Corporation (the “Company”) entered into an Underwriting Agreement with J.P. Morgan Securities Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several underwriters named in Schedule 1 of the Underwriting Agreement (collectively, the “Underwriters”), relating to the issuance and sale of 5,300,000 shares of common stock, par value $0.001 per share, of the Company (the “Shares”). The Underwriters were also granted an option to purchase up to an additional 795,000 Shares. The offering of the Shares (the “Public Offering”) was registered under the Securities Act of 1933, as amended (the “Securities Act”), pursuant to the Company’s Registration Statement on Form S-3 (Registration No. 333-159614) filed with the Securities and Exchange Commission on May 29, 2009, as amended by a pre-effective amendment filed on June 9, 2009. The Underwriting Agreement contains customary representations, warranties and covenants as well as customary indemnification by each of the Company and the Underwriters against certain liabilities and customary contribution provisions in respect of those liabilities.

The Public Offering closed on September 29, 2009. The issue price of each Share was $18.50. The Company received net proceeds from the Public Offering of approximately $93.4 million, after deducting Underwriters’ discounts of approximately $4.4 million and other offering expenses.

A copy of the Underwriting Agreement is filed as Exhibit 1.1 to this Current Report on Form 8-K and the contents thereof are incorporated herein by reference.

Purchase Agreement

On September 23, 2009, the Company entered into a Purchase Agreement (the “Purchase Agreement”) with Credit Suisse Securities (USA) LLC and J.P. Morgan Securities Inc., as representatives of the initial purchasers named in Schedule A of the Purchase Agreement (collectively, the “Initial Purchasers”) to sell 1,250,000 shares of the Company’s 8.00% Convertible Perpetual Preferred Stock, par value $0.001 per share and liquidation preference of $100 per share (the “Convertible Preferred Stock”), in accordance with a private placement (the “Private Placement”) conducted pursuant to Rule 144A under the Securities Act. The Initial Purchasers were also granted an option to purchase up to an additional 350,000 shares of Convertible Preferred Stock. The material terms of the Convertible Preferred Stock issued in the Private Placement are described below in Item 3.02.

A copy of the Purchase Agreement is filed as Exhibit 10.1 to this Current Report on Form 8-K and the contents thereof are incorporated herein by reference.

Item 3.02. Unregistered Sales of Equity Securities.

The information set forth above in Item 1.01 regarding the Purchase Agreement is hereby incorporated by reference into this Item 3.02. On September 29, 2009, the Company completed a private placement of 1,400,000 shares of the Company’s Convertible Preferred Stock, to be resold to a group of qualified institutional buyers pursuant to the Rule 144A under the Securities Act. The private placement included 150,000 shares of Convertible Preferred Stock issued upon the exercise of the Initial Purchasers’ option to purchase additional shares of Convertible Preferred Stock. The Convertible Preferred Stock was sold pursuant to the terms of Purchase Agreement and the issue price of each share of Convertible Preferred Stock was $100. The Company received net proceeds from the private placement of approximately $135.5 million, after deducting Initial Purchasers’ discounts of approximately $4.2 million and other offering expenses.

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Pursuant to the Statement of Resolutions Establishing the Convertible Preferred Stock (the “Statement of Resolutions”), each share of Convertible Preferred Stock is convertible, at the holders option, into a number of shares of the Company’s common stock equal to the liquidation preference of $100 divided by the conversion price, which is initially $22.20 per share and is subject to specified adjustments. This results in an initial conversion rate of approximately 4.5045 shares of common stock per share of Convertible Preferred Stock. Based on the initial conversion price, approximately 6,306,300 shares of Common Stock would be issuable upon conversion of all of the outstanding shares of the Convertible Preferred Stock.

The annual dividend on each share of Convertible Preferred Stock is $8.00 and is payable quarterly, in arrears, on each January 1, April 1, July 1 and October 1, commencing on January 1, 2010, when, as and if declared by the Company’s board of directors. No dividends will accrue or accumulate prior to September 29, 2009. The Company may, at its option, pay dividends in cash, common stock or any combination thereof.

Except as required by law or the Company’s Restated Articles of Incorporation, holders of the Convertible Preferred Stock will have no voting rights unless dividends fall into arrears for six quarterly periods (whether or not consecutive). Until such arrearage is paid in full, the holders will be entitled to elect two directors and the number of directors on the Company’s board of directors will increase by that same number.

At any time on or after October 1, 2014, the Company may at its option cause all outstanding shares of the Convertible Preferred Stock to be automatically converted into common stock at the then-prevailing conversion price, if the closing sale price of the Company’s common stock exceeds 150% of the then-prevailing conversion price for a specified period prior to the conversion.

If a holder elects to convert shares of Convertible Preferred Stock upon the occurrence of certain specified fundamental changes, the Company may be obligated to deliver an additional number of shares above the applicable conversion rate to compensate the holder for lost option value.

Item 3.03. Material Modification to Rights of Security Holders.

In addition, pursuant to the Statement of Resolutions setting forth the preferences, qualifications, limitations, restrictions and rights of the Convertible Preferred Stock, the ability of the Company to declare or pay dividends or distributions on, or repurchase, redeem or otherwise acquire for consideration, shares of its Common Stock will be subject to restrictions in the event that the Company fails to declare and pay full dividends (or declare and set aside a sum sufficient for payment thereof) on its Convertible Preferred Stock. These restrictions are more fully set forth in the Statement of Resolutions described in Item 5.03 and attached as Exhibit 3.1 to this Current Report on Form 8-K, the terms of which are incorporated into this Item 3.02 by reference.

Item 5.03 Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.

The information contained in Items 3.02 and 3.03 is hereby incorporated by reference. The Statement of Resolutions, which authorizes a total of 1,600,000 shares of 8% Convertible Preferred Stock, was filed with the Secretary of State of the State of Texas on September 29, 2009 and was effective upon filing.

Item 8.01. Other Events.

On September 23, 2009, the Company issued a press release announcing pricing of the Public Offering. A copy of the press release is attached as Exhibit 99.1 to this Current Report on Form 8-K.

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On September 23, 2009, the Company issued a press release announcing pricing of the Private Placement. A copy of the press release is attached as Exhibit 99.2 to this Current Report on Form 8-K.

On September 29, 2009, the Company issued a press release announcing consummation of the transactions contemplated in the Public Offering. A copy of the press release is attached as Exhibit 99.3 to this Current Report on Form 8-K.

On September 29, 2009, the Company issued a press release announcing consummation of the transactions contemplated in the Private Placement. A copy of the press release is attached as Exhibit 99.4 hereto to this Current Report on Form 8-K.

Item 9.01. Financial Statements and Exhibits.

(d) Exhibits.

Number	Exhibit
1.1	Underwriting Agreement dated September 23, 2009 among the Company, J.P. Morgan Securities Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Underwriters named therein.
3.1	Statement of Resolutions Establishing the 8.00% Convertible Perpetual Preferred Stock of ATP Oil & Gas Corporation.
4.1	Form of Stock Certificate for 8.00% Convertible Perpetual Preferred Stock.
10.1	Purchase Agreement dated September 23, 2009 among the Company, J.P. Morgan Securities Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Initial Purchasers named therein.
99.1	Press Release dated September 23, 2009 (Public Offering).
99.2	Press Release dated September 23, 2009 (Private Placement).
99.3	Press Release dated September 29, 2009 (Public Offering).
99.4	Press Release dated September 29, 2009 (Private Placement).

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SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	ATP OIL & GAS CORPORATION
Date: September 29, 2009	By:	/s/    ALBERT L. REESE JR.
		Albert L. Reese Jr.
		Chief Financial Officer

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EXHIBIT INDEX

Number	Exhibit
1.1	Underwriting Agreement dated September 23, 2009 among the Company, J.P. Morgan Securities Inc. and Credit Suisse Securities (USA) LLC, as representatives of the several Underwriters named therein.
3.1	Statement of Resolutions Establishing the 8.00% Convertible Perpetual Preferred Stock of ATP Oil & Gas Corporation.
4.1	Form of Stock Certificate for 8.00% Convertible Perpetual Preferred Stock.
10.1	Purchase Agreement dated September 23, 2009 among the Company, Credit Suisse Securities (USA) LLC and J.P. Morgan Securities Inc., as representatives of the several Initial Purchasers named therein.
99.1	Press Release dated September 23, 2009 (Public Offering).
99.2	Press Release dated September 23, 2009 (Private Placement).
99.3	Press Release dated September 29, 2009 (Public Offering).
99.4	Press Release dated September 29, 2009 (Private Placement).

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EX-1.1

Exhibit 1.1

J.P. MORGAN SECURITIES INC.

ATP OIL & GAS CORPORATION

5,300,000 Shares of Common Stock

Underwriting Agreement

September 23, 2009

J.P. Morgan Securities Inc.

Credit Suisse Securities (USA) LLC

As Representatives of the

several Underwriters listed

in Schedule 1 hereto

c/o J.P. Morgan Securities Inc.

383 Madison Avenue

New York, New York 10179

Ladies and Gentlemen:

ATP Oil & Gas Corporation, a Texas corporation (the “Company”), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), an aggregate of 5,300,000 shares of Common Stock, par value $ 0.001 per share, of the Company (the “Underwritten Shares”) and, at the option of the Underwriters, up to an additional 795,000 shares of Common Stock of the Company (the “Option Shares”). The Underwritten Shares and the Option Shares are herein referred to as the “Shares”. The shares of Common Stock of the Company to be outstanding after giving effect to the sale of the Shares are referred to herein as the “Stock”.

The Company hereby confirms its agreement with the several Underwriters concerning the purchase and sale of the Shares, as follows:

1. Registration Statement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement (File No. 333-159614), including a prospectus, relating to the Shares. Such registration statement, as amended at the time it became effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement”; and as used herein, the term “Preliminary Prospectus” means each prospectus included in such registration statement (and any amendments thereto) before effectiveness, any prospectus filed with the Commission pursuant to Rule 424(a) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the prospectus in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Shares. If the Company

has filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement. Any reference in this Agreement to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Prospectus, as the case may be, and any reference to “amend”, “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”) that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

At or prior to the Applicable Time (as defined below), the Company had prepared the following information (collectively with the pricing information set forth on Annex B, the “Pricing Disclosure Package”): a Preliminary Prospectus dated September 22, 2009 and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Annex B hereto.

“Applicable Time” means 8:00 p.m. New York City time, on September 23, 2009.

2. Purchase of the Shares by the Underwriters.

(a) The Company agrees to issue and sell the Underwritten Shares to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective number of Underwritten Shares set forth opposite such Underwriter’s name in Schedule 1 hereto at a price per share (the “Purchase Price”) of $17.6675.

In addition, the Company agrees to issue and sell the Option Shares to the several Underwriters as provided in this Agreement, and the Underwriters, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from the Company the Option Shares at the Purchase Price less an amount per share equal to any dividends or distributions declared by the Company and payable on the Underwritten Shares but not payable on the Option Shares.

If any Option Shares are to be purchased, the number of Option Shares to be purchased by each Underwriter shall be the number of Option Shares which bears the same ratio to the aggregate number of Option Shares being purchased as the number of Underwritten Shares set forth opposite the name of such Underwriter in Schedule 1 hereto (or such number increased as set forth in Section 10 hereof) bears to the aggregate number of Underwritten Shares being purchased from the Company by the several Underwriters, subject, however, to such adjustments to eliminate any fractional Shares as the Representatives in their sole discretion shall make.

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The Underwriters may exercise the option to purchase Option Shares at any time in whole, or from time to time in part, on or before the thirtieth day following the date of the Prospectus, by written notice from the Representatives to the Company. Such notice shall set forth the aggregate number of Option Shares as to which the option is being exercised and the date and time when the Option Shares are to be delivered and paid for, which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date or later than the tenth full business day (as hereinafter defined) after the date of such notice (unless such time and date are postponed in accordance with the provisions of Section 10 hereof). Any such notice shall be given at least two business days prior to the date and time of delivery specified therein.

(b) The Company understands that the Underwriters intend to make a public offering of the Shares as soon after the effectiveness of this Agreement as in the judgment of the Representatives is advisable, and initially to offer the Shares on the terms set forth in the Prospectus. The Company acknowledges and agrees that the Underwriters may offer and sell Shares to or through any affiliate of an Underwriter.

(c) Payment for the Shares shall be made by wire transfer in immediately available funds to the account specified by the Company to the Representatives in the case of the Underwritten Shares, at the offices of Cahill Gordon & Reindel LLP at 10:00 A.M., New York City time, on September 29, 2009, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representatives and the Company may agree upon in writing or, in the case of the Option Shares, on the date and at the time and place specified by the Representatives in the written notice of the Underwriters’ election to purchase such Option Shares. The time and date of such payment for the Underwritten Shares is referred to herein as the “Closing Date”, and the time and date for such payment for the Option Shares, if other than the Closing Date, is herein referred to as the “Additional Closing Date”.

Payment for the Shares to be purchased on the Closing Date or the Additional Closing Date, as the case may be, shall be made against delivery to the Representatives for the respective accounts of the several Underwriters of the Shares to be purchased on such date or the Additional Closing Date, as the case may be, with any transfer taxes payable in connection with the sale of such Shares duly paid by the Company. Delivery of the Shares shall be made through the facilities of The Depository Trust Company (“DTC”) unless the Representatives shall otherwise instruct. The certificates for the Shares will be made available for inspection and packaging by the Representatives at the office of DTC or its designated custodian not later than 1:00 P.M., New York City time, on the business day prior to the Closing Date or the Additional Closing Date, as the case may be.

(d) The Company acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of Shares contemplated hereby (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person. Additionally, neither the Representatives nor any other Underwriter is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company shall consult with its own advisors concerning such matters and shall be responsible for making its own independent investigation and appraisal of

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the transactions contemplated hereby, and the Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by the Underwriters of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

3. Representations and Warranties of the Company. The Company represents and warrants to each Underwriter that:

(a) Preliminary Prospectus. No order preventing or suspending the use of any Preliminary Prospectus has been issued by the Commission, and each Preliminary Prospectus included in the Pricing Disclosure Package, at the time of filing thereof, complied in all material respects with the Securities Act, and no Preliminary Prospectus, at the time of filing thereof, contained any untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in any Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(b) Pricing Disclosure Package. The Pricing Disclosure Package as of the Applicable Time did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in such Pricing Disclosure Package, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(c) Issuer Free Writing Prospectus. Other than the Registration Statement, the Preliminary Prospectus and the Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not prepared, used, authorized, approved or referred to and will not prepare, use, authorize, approve or refer to any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Shares (each such communication by the Company or its agents and representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Annex B hereto, each electronic road show and any other written communications approved in writing in advance by the Representatives. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act, has been or will be (within the

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time period specified in Rule 433) filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with the Preliminary Prospectus accompanying, or delivered prior to delivery of, such Issuer Free Writing Prospectus, did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus or Preliminary Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in such Issuer Free Writing Prospectus or Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof.

(d) Registration Statement and Prospectus. The Registration Statement has been declared effective by the Commission. No order suspending the effectiveness of the Registration Statement has been issued by the Commission, and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Shares has been initiated or threatened by the Commission; as of the applicable effective date of the Registration Statement and any post-effective amendment thereto, the Registration Statement and any such post-effective amendment complied and will comply in all material respects with the Securities Act, and did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus will not contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 7(b) hereof. The Company meets, and at the time the Registration Statement was originally declared effective the Company met, the applicable requirements for use of Form S-3 under the Securities Act. The Company also meets the requirements for use of Form S-3 under the Securities Act referenced in Rule 5110(b)(7)(C)(i) of the Financial Industry Regulatory Authority (“FINRA”).

(e) Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Prospectus and the Pricing Disclosure Package, when they were filed with the Commission conformed in all material respects to the requirements of the Exchange Act, and none of such documents contained any untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in

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the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the Registration Statement, the Prospectus or the Pricing Disclosure Package, when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act and will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(f) Financial Statements. The financial statements (including the related notes thereto) of the Company and its consolidated subsidiaries included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly the financial position of the Company and its consolidated subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; such financial statements have been prepared in conformity with generally accepted accounting principles in the United States applied on a consistent basis throughout the periods covered thereby, and any supporting schedules included or incorporated by reference in the Registration Statement present fairly the information required to be stated therein; and the other financial information included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus has been derived from the accounting records of the Company and its consolidated subsidiaries and presents fairly the information shown thereby.

(g) No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (i) there has not been any material change in the capital stock (other than the issuance of shares of Common Stock upon exercise of stock options and warrants described as outstanding in, and the grant of options and awards under existing equity incentive plans described in, the Registration Statement, the Pricing Disclosure Package and the Prospectus), short-term debt or long-term debt of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development involving a prospective material adverse change, in or affecting the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole; (ii) neither the Company nor any of its subsidiaries has entered into any transaction or agreement (whether or not in the ordinary course of business) that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole; and (iii) neither the Company nor any of its subsidiaries has sustained any loss or interference with its business that is material to the Company and its subsidiaries taken as a whole and that is either from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority, except in each case as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

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(h) Organization and Good Standing. The Company and each of its subsidiaries have been duly organized and are validly existing and in good standing under the laws of their respective jurisdictions of organization, are duly qualified to do business and are in good standing in each jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, and have all power and authority necessary to own or hold their respective properties and to conduct the businesses in which they are engaged, except where the failure to be so qualified or in good standing or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the business, financial position, or results of operations of the Company and its subsidiaries taken as a whole or on the performance by the Company of its obligations under this Agreement (a “Material Adverse Effect”). The Company does not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed in Exhibit 21 to the Registration Statement.

(i) Capitalization. The Company has an authorized capitalization as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the heading “Capitalization”; all the outstanding shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable and are not subject to any pre-emptive or similar rights; except as described in or expressly contemplated by the Pricing Disclosure Package and the Prospectus, there are no outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and all the outstanding shares of capital stock or other equity interests of each subsidiary owned, directly or indirectly, by the Company have been duly and validly authorized and issued, are fully paid and non-assessable (except, in the case of any foreign subsidiary, for directors’ qualifying shares) and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party.

(j) Stock Options. With respect to the stock options (the “Stock Options”) granted pursuant to the stock-based compensation plans of the Company and its subsidiaries (the “Company Stock Plans”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Code so qualifies, (ii) each grant of a Stock Option was duly authorized no later than the date on which the grant of such Stock Option was by its terms to be effective (the “Grant Date”) by all necessary corporate action, including, as applicable, approval by the board of directors of the Company (or a duly constituted and authorized committee thereof) and any required stockholder approval by the necessary number of votes or written consents, and the award agreement governing such grant (if any) was duly executed and delivered by each party thereto, (iii) each such grant was made in accordance with the terms of the Company Stock Plans, the Exchange Act and all other applicable laws and regulatory rules or requirements, including

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the rules of the Nasdaq Global Select Market and any other exchange on which Company securities are traded, and (iv) each such grant was properly accounted for in accordance with GAAP in the financial statements (including the related notes) of the Company and disclosed in the Company’s filings with the Commission in accordance with the Exchange Act and all other applicable laws. The Company has not knowingly granted, and there is no and has been no policy or practice of the Company of granting, Stock Options prior to, or otherwise coordinating the grant of Stock Options with, the release or other public announcement of material information regarding the Company or its subsidiaries or their results of operations or prospects.

(k) Due Authorization. The Company has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of this Agreement and the consummation by it of the transactions contemplated hereby has been duly and validly taken.

(l) Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(m) The Shares. The Shares to be issued and sold by the Company hereunder have been duly authorized and, when issued and delivered and paid for as provided herein, will be duly and validly issued, will be fully paid and nonassessable and will conform to the descriptions thereof in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and the issuance of the Shares is not subject to any preemptive or similar rights.

(n) [Reserved].

(o) Descriptions of this Agreement and the Lock-up” Agreements. This Agreement and each of the “lock-up” agreements executed and delivered to the Representatives pursuant to Section 6(m) conforms in all material respects to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(p) No Violation or Default. Neither the Company nor any of its subsidiaries is (i) in violation of its charter or by-laws or similar organizational documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (ii) and (iii) above, for any such default or violation that would not, individually or in the aggregate, have a Material Adverse Effect.

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(q) No Conflicts. The execution, delivery and performance by the Company of each of this Agreement, the issuance and sale of the Shares and the consummation of the transactions contemplated by this Agreement and described in the Pricing Disclosure Package and Prospectus will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (ii) result in any violation of the provisions of the charter or by-laws or similar organizational documents of the Company or any of its subsidiaries or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (i) and (iii) above, for any such conflict, breach, violation or default that would not, individually or in the aggregate, have a Material Adverse Effect.

(r) No Consents Required. No consent, approval, authorization, order, license, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of each of this Agreement, the issuance and sale of the Shares and the consummation of the transactions contemplated by this Agreement and described in the Pricing Disclosure Package and Prospectus, except for the registration of the Shares under the Securities Act and such consents, approvals, authorizations, orders and registrations or qualifications as may be required by FINRA or The NASDAQ Global Select Market and under applicable state securities laws in connection with the purchase and distribution of the Shares by the Underwriters.

(s) Legal Proceedings. Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no legal, governmental or regulatory investigations, actions, suits or proceedings pending to which the Company or any of its subsidiaries is or may be a party or to which any property of the Company or any of its subsidiaries is or may be the subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, could reasonably be expected to have a Material Adverse Effect; no such investigations, actions, suits or proceedings are threatened by any governmental or regulatory authority.

(t) Independent Accountants. PricewaterhouseCoopers LLP, who have certified certain financial statements of the Company and its subsidiaries and Deloitte & Touche LLP, who have certified certain financial statements of the Company and its Subsidiaries, are each an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Company Accounting Oversight Board (United States) and as required by the Securities Act.

(u) Title to Real and Personal Property. Except as otherwise set forth in the Registration Statement, the Pricing Disclosure Package or the Prospectus or such as in the

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aggregate does not now cause nor will it in the future cause a Material Adverse Effect, the Company and its subsidiaries have title to their properties as follows: (a) with respect to their wells (including leasehold interests and appurtenant personal property) and their non-producing oil and gas properties (including undeveloped locations on leases held by production and those leases not held by production), such title is valid and defensible and free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and restrictions, (b) with respect to their non-producing properties in exploration prospects, such title was investigated in accordance with customary industry procedures prior to the Company or its subsidiaries acquisition thereof; (c) with respect to their real property other than oil and gas interests, such title is good and marketable free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and restrictions; and (d) with respect to their personal property other than that appurtenant to its oil and gas interests, such title is free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and restrictions. No real property owned, leased, licensed, or used by the Company or its subsidiaries lies in an area which is, or to the knowledge of the Company will be, subject to restrictions which would prohibit, and no statements of facts relating to the actions or inaction of another person or entity or his or its ownership, leasing, licensing, or use of any real or personal property exists or will exist which would prevent, the continued effective ownership, leasing, licensing, exploration, development or production or use of such real property in the business of the Company as presently conducted or as the Registration Statement, the Pricing Disclosure Package or the Prospectus indicates they contemplate conducting, except as may be described in the Registration Statement, the Pricing Disclosure Package or the Prospectus or such as in the aggregate do not now cause and will not in the future reasonably be expected to cause a Material Adverse Effect.

(v) Title to Intellectual Property. The Company and its subsidiaries own or possess, or can acquire on reasonable terms, adequate patents, patent rights, licenses, inventions, copyrights, know-how, confidential information, trademarks, service marks, trade names or other intellectual property (collectively, “Intellectual Property”) necessary to carry on the business now operated by them, except where the failure to own or possess, or have the ability to acquire on reasonable terms such Intellectual Property would not, singularly or in the aggregate, reasonably be expected to cause a Material Adverse Effect. Neither the Company nor any subsidiary has received any notice of any infringement of or conflict with asserted rights of others with respect to any Intellectual Property that if determined adversely to the Company would, singly or in the aggregate, result in a Material Adverse Effect.

(w) Investment Company Act. The Company is not and, after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, will not be required to register as an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Investment Company Act”).

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(x) Taxes. The Company and its subsidiaries have on a timely basis paid all federal, state, local and foreign taxes and filed all tax returns required to be paid or filed through the date hereof (except in any case in which the failure to file would not reasonably be expected to result in a Material Adverse Effect); and except as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there is no tax deficiency that has been, or could reasonably be expected to be, asserted against the Company or any of its subsidiaries or any of their respective properties or assets, except for any tax deficiency that is currently being contested in good faith or would not result in a Material Adverse Effect.

(y) Licenses and Permits. The Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect; except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company and its Subsidiaries are in compliance with the terms and conditions of all such licenses, certificates, permits and authorizations, except where the failure to so comply would not, individually or in the aggregate, have a Material Adverse Effect; and except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such license, certificate, permit or authorization which, singly or in the aggregate, if subject to an unfavorable decision, ruling or finding would result in a Material Adverse Effect.

(z) No Labor Disputes. No labor disturbance by or dispute with employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent, and the Company is not aware of any existing or imminent labor disturbance by, or dispute with, the employees of any of its or its subsidiaries’ principal suppliers, contractors or customers, except as would not have a Material Adverse Effect.

(aa) Compliance with and Liability under Environmental Laws. (i) The Company and its subsidiaries (a) are, in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, requirements, decisions, judgments, decrees, and orders relating to pollution or the protection of the environment, natural resources or human health or safety, including those relating to the generation, storage, treatment, use, handling, transportation, Release or threat of Release of Hazardous Materials (collectively, “Environmental Laws”), (b) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under applicable Environmental Laws to conduct their respective businesses, (c) have not received notice of any actual or potential liability under or relating to, or actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any Release or threat of Release of Hazardous Materials, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, (d) are not conducting or paying for, in whole or in part, any investigation, remediation or other corrective

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action pursuant to any Environmental Law at any location, and (e) are not a party to any order, decree or agreement that imposes any obligation or liability under any Environmental Law, except for any such matter as would not, individually or in the aggregate reasonably be expected to have a Material Adverse Effect, and (ii) there are no costs or liabilities associated with Environmental Laws of or relating to the Company or its subsidiaries, except for any such matter as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and (iii) except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (a) there are no proceedings that are pending, or that are known to be contemplated, against the Company or any of its subsidiaries under any Environmental Laws in which a governmental entity is also a party, other than such proceedings regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed, and (b) the Company and its subsidiaries are not aware of any facts or issues regarding compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws, including the Release or threat of Release of Hazardous Materials, that could reasonably be expected to have a material effect on the capital expenditures, earnings or competitive position of the Company and its subsidiaries.

(bb) Hazardous Materials. There has been no storage, generation, transportation, use, handling, treatment, Release or threat of Release of Hazardous Materials by, relating to or caused by the Company or any of its subsidiaries (or, to the knowledge of the Company and its subsidiaries, any other entity (including any predecessor) for whose acts or omissions the Company or any of its subsidiaries is or could reasonably be expected to be liable) at, on, under or from any property or facility now or previously owned, operated or leased by the Company or any of its subsidiaries, or at, on, under or from any other property or facility, in violation of any Environmental Laws or in a manner or amount or to a location that could reasonably be expected to result in any liability of the Company or any of its subsidiaries under any Environmental Law, except for any violation or liability which would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. “Hazardous Materials” means any material, chemical, substance ,waste, pollutant, contaminant, compound, mixture, or constituent thereof, in any form or amount, including petroleum (including crude oil or any fraction thereof) and petroleum products, natural gas, natural gas liquids, asbestos and asbestos containing materials, naturally occurring radioactive materials, brine, and drilling mud, regulated or which can give rise to liability under any Environmental Law. “Release” means any spilling, leaking, seepage, pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, disposing, depositing, dispersing, or migrating in, into or through the environment, or in, into from or through any building or structure.

(cc) Compliance with ERISA. The minimum funding standard under Section 302 of the Employee Retirement Income Security Act of 1974, as amended, and the regulations and published interpretations thereunder (“ERISA”), has been satisfied by each “pension plan” (as defined in Section 3(2) of ERISA) which has been established or maintained by the Company, and the trust forming part of each such plan which is intended to be qualified under Section 401 of the Internal Revenue Code of 1986, as amended (the “Code”), is so qualified; each of the Company and the Subsidiaries has fulfilled its obligations, if any, under Section 515 of ERISA; neither the Company nor any

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subsidiary maintains and is required to contribute to a “welfare plan” (as defined in Section 3(1) of ERISA) which provides retiree or other post-employment welfare benefits or insurance coverage (other than “continuation coverage” (as defined in Section 602 of ERISA)); each pension plan and welfare plan established or maintained by the Company and/or one of the subsidiaries is in compliance with the currently applicable provisions of ERISA, except where the failure to comply would not cause a Material Adverse Effect; no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any pension plan or welfare plan (excluding transactions effected pursuant to statutory or administrative exemption) that could reasonably be expected to result in a material liability to the Company or its subsidiaries; and neither the Company nor any Subsidiary has incurred or could reasonably be expected to incur any withdrawal liability under Section 4201 of ERISA, any liability under Section 4062, 4063, or 4064 of ERISA, or any other liability under Title IV of ERISA.

(dd) Disclosure Controls. The Company and its subsidiaries maintain an effective system of “disclosure controls and procedures” (as defined in Rule 13a-15(e) of the Exchange Act) that complies with the requirements of the Exchange Act and that has been designed to ensure that information required to be disclosed by the Company in reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including controls and procedures designed to ensure that such information is accumulated and communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure. The Company and its subsidiaries have carried out evaluations of the effectiveness of their disclosure controls and procedures as required by Rule 13a-15 of the Exchange Act.

(ee) Accounting Controls. The Company and its subsidiaries maintain systems of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of, their respective principal executive and principal financial officers, or persons performing similar functions, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, including, but not limited to, internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company is not aware of (i) any significant deficiencies or material weaknesses in the design or operation of internal controls or (ii) any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting which are likely to adversely affect the Company’s ability to record, process, summarize and report financial information. The Company’s auditors and the Audit

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Committee of the Board of Directors of the Company have been advised of: (i) all significant deficiencies and material weaknesses in the design or operation of internal controls over financial reporting which have adversely affected or are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information; and (ii) any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting.

(ff) Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, including business interruption insurance, which insurance is in amounts and insures against such losses and risks as are customary for the businesses in which they are engaged; all such policies insuring the Company and its subsidiaries are in full force and effect; and neither the Company nor any of its subsidiaries has received notice from any insurer or agent of such insurer that it will not be able to renew insurance coverage as and when such coverage expires or to obtain coverage acceptable to the Company at reasonable cost from similar insurers as may be necessary to continue its business.

(gg) No Unlawful Payments. Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or other person associated with or acting on behalf of the Company or any of its subsidiaries has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; (iii) violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977; or (iv) made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment.

(hh) Compliance with Money Laundering Laws. The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(ii) Compliance with OFAC. None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Department of the Treasury (“OFAC”); and the Company will not, directly or indirectly, use the proceeds of the offering of the Shares hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

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(jj) No Restrictions on Subsidiaries. No subsidiary of the Company that is a party to the Credit Agreement, dated June 27, 2008 to which the Company is a party, is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s properties or assets to the Company or any other subsidiary of the Company.

(kk) No Broker’s Fees. Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against the Company or any of its subsidiaries or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Shares.

(ll) No Registration Rights. No person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Securities Act by reason of the filing of the Registration Statement with the Commission or the issuance and sale of the Shares.

(mm) No Stabilization. The Company has not taken, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Shares.

(nn) Margin Rules. The application of the proceeds received by the Company from the issuance, sale and delivery of the Shares as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus will not violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

(oo) Status under the Securities Act. At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that the Company or any offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Shares and at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 under the Securities Act.

(pp) Reserve Report Data. The oil and gas reserve estimates of the Company contained or incorporated by reference into the Registration Statement, Pricing Disclosure Package and the Prospectus have been prepared by (i) Ryder Scott Company, L.P., (ii) Collarini Associates and (iii) DeGolyer & MacNaughton (collectively, the “Engineers”), and the Company has no reason to believe that such estimates do not fairly reflect the oil and gas reserves of the Company at the dates indicated. The information underlying the estimates of the reserves of the Company and its subsidiaries supplied by the

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Company to the Engineers, for the purposes of preparing the reserve reports of Company and its subsidiaries referenced in the Registration Statement, Pricing Disclosure Package and Prospectus (the “Reserve Reports”), was true and correct in all material respects on the date of each such Reserve Report; the estimates of future capital expenditures and other future exploration and development costs supplied to the Engineers were prepared in good faith and with a reasonable basis; the information provided to the Engineers was prepared in good faith and with a reasonable basis. Other than production of the reserves in the ordinary course of business and intervening product price fluctuations described in the Registration Statement, Pricing Disclosure Package and the Prospectus, the Company is not aware of any facts or circumstances that would cause a Material Adverse Change in the reserves or the present value of future net cash flows therefrom as described in the Registration Statement, Pricing Disclosure Package and the Prospectus. Each of the Engineers is an independent reserve engineer with respect to the Company and its subsidiaries.

4. Further Agreements of the Company. The Company covenants and agrees with each Underwriter that:

(a) Required Filings. The Company will file the final Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act, will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; will file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Shares and will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, on the business day next succeeding the date of this Agreement in such quantities as the Representatives may reasonably request.

(b) Delivery of Copies. The Company will deliver, without charge, to each Underwriter (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto (without exhibits) and (B) during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein and each Issuer Free Writing Prospectus) as the Representatives may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Shares as in the opinion of counsel for the Underwriters a prospectus relating to the Shares is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Shares by any Underwriter or dealer.

(c) Amendments or Supplements, Issuer Free Writing Prospectuses. Before preparing, using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement or the Prospectus, whether before or after the time that the Registration Statement becomes

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effective, the Company will furnish to the Representatives and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not prepare, use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus or file any such proposed amendment or supplement to which the Representatives reasonably objects.

(d) Notice to the Representatives. The Company will advise the Representatives promptly, and confirm such advice in writing, (i) when the Registration Statement has become effective; (ii) when any amendment to the Registration Statement has been filed or becomes effective; (iii) when any supplement to the Prospectus or any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed; (iv) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (v) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus, any of the Pricing Disclosure Package or the Prospectus or the initiation or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (vi) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, the Pricing Disclosure Package or any Issuer Free Writing Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus, the Pricing Disclosure Package or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; and (vii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Shares for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and the Company will use its best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus, any of the Pricing Disclosure Package or the Prospectus or suspending any such qualification of the Shares and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

(e) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriters and to such dealers as the Representatives may designate such amendments or supplements to the Prospectus as may be necessary so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with law and (2) if at any time prior to the Closing Date (i) any event shall occur or condition shall exist as a result of which the Pricing Disclosure Package as then amended

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or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Pricing Disclosure Package to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representatives may designate such amendments or supplements to the Pricing Disclosure Package as may be necessary so that the statements in the Pricing Disclosure Package as so amended or supplemented will not, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, be misleading or so that the Pricing Disclosure Package will comply with law.

(f) Blue Sky Compliance. The Company will qualify the Shares for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Representatives shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Shares; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(g) Earning Statement. The Company will make generally available to its security holders and the Representatives as soon as practicable an earning statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the “effective date” (as defined in Rule 158) of the Registration Statement.

(h) Clear Market. For a period of 90 days after the date of the Prospectus, the Company will not (i) offer, pledge, announce the intention to sell, 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 or otherwise transfer or dispose of, directly or indirectly, any shares of Stock or any securities convertible into or exercisable or exchangeable for Stock (other than the concurrent offering of convertible preferred stock as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus) or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Stock, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise, without the prior written consent of the Representatives, other than the Shares to be sold hereunder and any shares of Stock of the Company issued upon the exercise of options granted under stock option plans described in the Registration Statement, the Pricing Disclosure Package and the Prospectus. Notwithstanding the foregoing, if (1) during the last 17 days of the 90-day restricted period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (2) prior to the expiration of the 90-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the

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90-day period, the restrictions imposed by this Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

(i) Use of Proceeds. The Company will apply the net proceeds from the sale of the Shares as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the heading “Use of proceeds”.

(j) No Stabilization. The Company will not take, directly or indirectly, any action designed to or that could reasonably be expected to cause or result in any stabilization or manipulation of the price of the Stock.

(k) Exchange Listing. The Company will use its best efforts to list for quotation the Shares on the Nasdaq Global Select Market (the “Nasdaq Market”)

(l) Reports. So long as the Shares are outstanding, the Company will furnish to the Representatives, as soon as they are available, copies of all reports or other communications (financial or other) furnished to holders of the Shares, and copies of any reports and financial statements furnished to or filed with the Commission or any national securities exchange or automatic quotation system; provided the Company will be deemed to have furnished such reports and financial statements to the Representatives to the extent they are filed on the Commission’s Electronic Data Gathering, Analysis, and Retrieval system.

(m) Record Retention. The Company will, pursuant to reasonable procedures developed in good faith, retain copies of each Issuer Free Writing Prospectus that is not filed with the Commission in accordance with Rule 433 under the Securities Act.

5. Certain Agreements of the Underwriters. Each Underwriter hereby represents and agrees that:

(a) It has not used, authorized use of, referred to or participated in the planning for use of, and will not use, authorize use of, refer to or participate in the planning for use of, any “free writing prospectus”, as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Securities Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Annex B or prepared pursuant to Section 3(c) or Section 4(c) above (including any electronic road show), or (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”).

(b) It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Shares unless such terms have previously been included in a free writing prospectus filed with the Commission;

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provided that Underwriters may use a term sheet substantially in the form of Annex C hereto without the consent of the Company; provided further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet.

6. Conditions of Underwriters’ Obligations. The obligation of each Underwriter to purchase the Underwritten Shares on the Closing Date or the Option Shares on the Additional Closing Date, as the case may be, as provided herein is subject to the performance by the Company of its covenants and other obligations hereunder and to the following additional conditions:

(a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose or pursuant to Section 8A under the Securities Act shall be pending before or threatened by the Commission; the Prospectus and each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Representatives.

(b) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date or the Additional Closing Date, as the case may be; and the statements of the Company and its officers made in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date or the Additional Closing Date, as the case may be.

(c) No Downgrade. Subsequent to the earlier of (A) the Applicable Time and (B) the execution and delivery of this Agreement, if there are any debt securities or preferred stock of, or guaranteed by, the Company or any of its subsidiaries that are rated by a “nationally recognized statistical rating organization,” as such term is defined by the Commission for purposes of Rule 436(g)(2) under the Securities Act, (i) no downgrading shall have occurred in the rating accorded any such debt securities or preferred stock and (ii) no such organization shall have publicly announced that it has under surveillance or review, or has changed its outlook with respect to, its rating of any such debt securities or preferred stock (other than an announcement with positive implications of a possible upgrading).

(d) No Material Adverse Change. No event or condition of a type described in Section 3(g) hereof shall have occurred or shall exist, which event or condition is not described in the Pricing Disclosure Package (excluding any amendment or supplement thereto) and the Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the Representatives makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus.

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(e) Officers’ Certificate. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, a certificate of the chief financial officer or chief accounting officer of the Company and one additional senior executive officer of the Company who is satisfactory to the Representatives (i) confirming that such officers have carefully reviewed the Registration Statement, the Pricing Disclosure Package and the Prospectus and, to the knowledge of such officers, the representations set forth in Sections 3(b) and 3(d) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date or the Additional Closing Date, as the case may be, and (iii) to the effect set forth in paragraphs (a), (c) and (d) above.

(f) Comfort Letters. (i) On the (A) date of this Agreement each of PricewaterhouseCoopers LLP and Deloitte & Touche LLP and (B) Closing Date or the Additional Closing Date, as the case may be, PricewaterhouseCoopers LLP shall have furnished to the Representatives, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus; provided, that the letter delivered on the Closing Date or the Additional Closing Date, as the case may be, shall use a “cut-off” date no more than three business days prior to such Closing Date or such Additional Closing Date, as the case may be.

(ii) On the Closing Date or the Additional Closing Date each of (A) Ryder Scott Company, L.P. and (B) Collarini Associates and shall have furnished to the Representatives, at the request of the Company, a letter dated the respective date of delivery thereof addressed to the Underwriters, in form and substance satisfactory to the Representatives, stating the conclusions and findings of such firm with respect to the oil and natural gas reserves of the Company.

(g) Opinion and 10b-5 Statement of Counsel for the Company. Jackson Walker L.L.P., counsel for the Company, shall have furnished to the Representatives, at the request of the Company, their written opinion and 10b-5 statement, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, to the effect set forth in Annex A-1 hereto.

(h) Chief Financial Officer’s Certificate. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, a certificate of the Chief Financial Officer of the Company to the effect that, as of the Closing Date or the Additional Closing Date, as the case may be, in the form and substance reasonably satisfactory to the Representatives, to the effect set forth on Exhibit B hereto.

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(i) Opinion and 10b-5 Statement of Counsel for the Underwriters. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion and 10b-5 statement of Cahill Gordon & Reindel LLP, counsel for the Underwriters, with respect to such matters as the Representatives may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

(j) No Legal Impediment to Issuance. No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Shares; and no injunction or order of any federal, state or foreign court shall have been issued that would, as of the Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Shares.

(k) Good Standing. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, satisfactory evidence of the good standing of the Company in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

(l) Exchange Listing. The Shares to be delivered on the Closing Date or Additional Closing Date, as the case may be, shall have been approved for listing on the Nasdaq Market, subject to official notice of issuance.

(m) Lock-up Agreements. The “lock-up” agreements, each substantially in the form of Exhibit A hereto, between you and certain shareholders, officers and directors of the Company relating to sales and certain other dispositions of shares of Stock or certain other securities, delivered to you on or before the date hereof, shall be full force and effect on the Closing Date or Additional Closing Date, as the case may be.

(n) Additional Documents. On or prior to the Closing Date or the Additional Closing Date, as the case may be, the Company shall have furnished to the Representatives such further certificates and documents as the Representatives may reasonably request.

7. Indemnification and Contribution.

(a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors and officers and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, (ii) or any untrue statement or alleged untrue statement of a

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material fact contained in the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus, any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Securities Act or any Pricing Disclosure Package (including any Pricing Disclosure Package that has subsequently been amended), or caused by any omission or alleged omission to state therein a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (b) below.

(b) Indemnification of the Company. Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in paragraph (a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Pricing Disclosure Package, it being understood and agreed upon that the only such information furnished by any Underwriter consists of the following information in the Prospectus furnished on behalf of each Underwriter: the concession and reallowance figures appearing in the third paragraph and the eleventh, twelfth and thirteenth paragraphs relating to Underwriter’s stabilization activities under the caption “Underwriting”.

(c) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “Indemnified Person”) shall promptly notify the person against whom such indemnification may be sought (the “Indemnifying Person”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under paragraph (a) or (b) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under paragraph (a) or (b) above. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person (who shall not, without the consent of the Indemnified Person, be counsel to the Indemnifying Person) to represent the Indemnified Person in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying

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Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interest between them. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceedings in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be paid or reimbursed as they are incurred. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by J.P. Morgan Securities Inc. and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

(d) Contribution. If the indemnification provided for in paragraphs (a) and (b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and the Underwriters on the other, from the offering of the Shares or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company, on the one hand, and the Underwriters, on the other, in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company, on the one hand, and the Underwriters, on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale

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of the Shares and the total underwriting discounts and commissions received by the Underwriters in connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Shares. The relative fault of the Company, on the one hand, and the Underwriters, on the other, shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(e) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 7 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of this Section 7, in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Shares exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to this Section 7 are several in proportion to their respective purchase obligations hereunder and not joint.

(f) Non-Exclusive Remedies. The remedies provided for in this Section 7 are not exclusive and shall not limit any rights or remedies which may otherwise be available to any Indemnified Person at law or in equity.

8. Effectiveness of Agreement. This Agreement shall become effective upon the execution and delivery hereof by the parties hereto.

9. Termination. This Agreement may be terminated in the absolute discretion of the Representatives, by notice to the Company, if after the execution and delivery of this Agreement and prior to the Closing Date or, in the case of the Option Shares, prior to the Additional Closing Date (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange, the American Stock Exchange, the Nasdaq Stock Market, the Chicago Board Options Exchange, the Chicago Mercantile Exchange or the Chicago Board of Trade; (ii) trading of any securities issued or guaranteed by the Company shall have been suspended on any exchange or in any over-the-counter market; (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York State authorities; or (iv) there shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, in the judgment of the Representatives, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus.

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10. Defaulting Underwriter.

(a) If, on the Closing Date or the Additional Closing Date, as the case may be, any Underwriter defaults on its obligation to purchase the Shares that it has agreed to purchase hereunder on such date, the non-defaulting Underwriters may in their discretion arrange for the purchase of such Shares by other persons satisfactory to the Company on the terms contained in this Agreement. If, within 36 hours after any such default by any Underwriter, the non-defaulting Underwriters do not arrange for the purchase of such Shares, then the Company shall be entitled to a further period of 36 hours within which to procure other persons satisfactory to the non-defaulting Underwriters to purchase such Shares on such terms. If other persons become obligated or agree to purchase the Shares of a defaulting Underwriter, either the non-defaulting Underwriters or the Company may postpone the Closing Date or the Additional Closing Date, as the case may be, for up to five full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “Underwriter” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule 1 hereto that, pursuant to this Section 10, purchases Shares that a defaulting Underwriter agreed but failed to purchase.

(b) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, does not exceed one-eleventh of the aggregate number of Shares to be purchased on such date, then the Company shall have the right to require each non-defaulting Underwriter to purchase the number of Shares that such Underwriter agreed to purchase hereunder on such date plus such Underwriter’s pro rata share (based on the number of Shares that such Underwriter agreed to purchase on such date) of the Shares of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

(c) If, after giving effect to any arrangements for the purchase of the Shares of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in paragraph (a) above, the aggregate number of Shares that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, exceeds one-eleventh of the aggregate amount of Shares to be purchased on such date, or if the Company shall not exercise the right described in paragraph (b) above, then this Agreement or, with respect to any Additional Closing Date, the obligation of the Underwriters to purchase Shares on the Additional Closing Date shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 10 shall be without liability on the part of the Company, except that the Company will continue to be liable for the payment of expenses as set forth in Section 11 hereof and except that the provisions of Section 7 hereof shall not terminate and shall remain in effect.

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(d) Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company or any non-defaulting Underwriter for damages caused by its default.

11. Payment of Expenses.

(a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the authorization, issuance, sale, preparation and delivery of the Shares and any taxes payable in that connection; (ii) the costs incident to the preparation, printing and filing under the Securities Act of the Registration Statement, the Preliminary Prospectus, any Issuer Free Writing Prospectus, any Pricing Disclosure Package and the Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the fees and expenses of the Company’s counsel and independent accountants; (iv) the fees and expenses incurred in connection with the registration or qualification of the Shares under the state or foreign securities or blue sky laws of such jurisdictions as the Representatives may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related fees and expenses of counsel for the Underwriters); (v) the cost of preparing stock certificates; (vi) the costs and charges of any transfer agent and any registrar; (vii) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, FINRA; (viii) all expenses incurred by the Company in connection with any “road show” presentation to potential investors; and (ix) all expenses and application fees related to the listing of the Shares on the Nasdaq Market.

(b) If (i) this Agreement is terminated pursuant to Section 9, (ii) the Company for any reason fails to tender the Shares for delivery to the Underwriters or (iii) the Underwriters decline to purchase the Shares for any reason permitted under this Agreement, the Company agrees to reimburse the Underwriters for all out-of-pocket costs and expenses (including the fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

12. Persons Entitled to Benefit of Agreement. This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and any controlling persons referred to in Section 7 hereof. Nothing in this Agreement is intended or shall be construed to give any other person any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein. No purchaser of Shares from any Underwriter shall be deemed to be a successor merely by reason of such purchase.

13. Survival. The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Underwriters contained in this Agreement or made by or on behalf of the Company or the Underwriters pursuant to this Agreement or any certificate delivered pursuant hereto shall survive the delivery of and payment for the Shares and shall remain in full force and effect, regardless of any termination of this Agreement or any investigation made by or on behalf of the Company or the Underwriters.

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14. Certain Defined Terms. For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) the term “business day” means any day other than a day on which banks are permitted or required to be closed in New York City; and (c) the term “subsidiary” has the meaning set forth in Rule 405 under the Securities Act.

15. Miscellaneous.

(a) Authority of J.P. Morgan Securities Inc. Any action by the Underwriters hereunder may be taken by J.P. Morgan Securities Inc. on behalf of the Underwriters, and any such action taken by J.P. Morgan Securities Inc. shall be binding upon the Underwriters.

(b) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to the Representatives c/o J.P. Morgan Securities Inc., 383 Madison Avenue 10179 (fax: (212) 622-8358); Attention Equity Syndicate Desk. Notices to the Company shall be given to it at 4600 Post Oak Place, Suite 200, Houston, Texas 77027, (fax: (713) 622-5101); Attention: John Tschirhart, with a copy to Jackson Walker L.L.P., 1401 McKinney St., Suite 1900, Houston, Texas 77010, (fax: (713) 308-4152; Attention: Richard Roth.

(c) Governing Law. This Agreement shall be governed by and construed in accordance with the laws of the State of New York applicable to agreements made and to be performed in such state.

(d) Counterparts. This Agreement may be signed in counterparts (which may include counterparts delivered by any standard form of telecommunication), each of which shall be an original and all of which together shall constitute one and the same instrument.

(e) Amendments or Waivers. No amendment or waiver of any provision of this Agreement, nor any consent or approval to any departure therefrom, shall in any event be effective unless the same shall be in writing and signed by the parties hereto.

(f) Headings. The headings herein are included for convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement.

(g) Research Analyst Independence. The Company acknowledges that the Underwriters’ research analysts and research departments are required to be independent from their respective investment banking divisions and are subject to certain regulations and internal policies, and that such Underwriters’ research analysts may hold views and make statements or investment recommendations and/or publish research reports with respect to the Company and/or the offering that differ from the views of their respective investment banking divisions. The Company hereby waives and releases, to the fullest extent permitted by law, any claims that the Company may have against the Underwriters with respect to any conflict of interest that may arise from the fact that the views expressed by their independent research analysts and research departments may be different from or inconsistent with the views or advice communicated to the Company by such Underwriters’ investment banking divisions. The Company acknowledges

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that each of the Underwriters is a full service securities firm and as such from time to time, subject to applicable securities laws, may effect transactions for its own account or the account of its customers and hold long or short positions in debt or equity securities of the companies that may be the subject of the transactions contemplated by this Agreement.

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If the foregoing is in accordance with your understanding, please indicate your acceptance of this Agreement by signing in the space provided below.

Very truly yours,
ATP OIL & GAS CORPORATION
By:	/s/ Leland E. Tate
Name:	Leland E. Tate
Title:	President

Accepted: September 23, 2009
J.P. MORGAN SECURITIES INC.
For itself and on behalf of the several Underwriters listed in Schedule 1 hereto.
By:	/s/ Yaw Asamoah-Duodu
	Authorized Signatory
	Executive Director
CREDIT SUISSE SECURITIES (USA) LLC
For itself and on behalf of the several Underwriters listed in Schedule 1 hereto.
By:	/s/ Timothy E. Perry
	Authorized Signatory

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C. K. COOPER & COMPANY, INC.
By:	/s/ Alexander G. Montano
	Authorized Signatory
CANACCORD ADAMS INC.
By:	/s/ Christian B. Gibson
	Authorized Signatory
FIG PARTNERS, LLC
By:	/s/ Geoffrey M. Hodgson
	Authorized Signatory
GLOBAL HUNTER SECURITIES, LLC
By:	/s/ Daniel O. Conwill, IV
	Authorized Signatory
HOWARD WEIL INCORPORATED
By:	/s/ Blair F. Scanlon, Jr.
	Authorized Signatory
JOHNSON RICE & COMPANY L.L.C.
By:	/s/ Joshua C. Cummings
	Authorized Signatory
NATIXIS BLEICHROEDER INC.
By:	/s/ Peter L. Wysong II
	Authorized Signatory
PRITCHARD CAPITAL PARTNERS, LLC.
By:	/s/ Todd Giustiniano
	Authorized Signatory
RODMAN & RENSHAW, LLC
By:	/s/ John J. Borer III
	Authorized Signatory

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SMH CAPITAL, INC.
By:	/s/ William W. Sprague
	Authorized Signatory
WUNDERLICH SECURITIES, INC.
By:	/s/ Martin Gaia
	Authorized Signatory

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Schedule 1

Underwriter	Number of Shares
J.P. Morgan Securities Inc.	1,987,500
Credit Suisse Securities (USA) LLC	1,987,500
Canaccord Adams Inc.	145,750
Pritchard Capital Partners, LLC.	145,750
SMH Capital, Inc.	145,750
Howard Weil Incorporated	132,500
Johnson Rice & Company L.L.C.	132,500
Wunderlich Securities, Inc.	132,500
C. K. Cooper & Company, Inc.	106,000
Global Hunter Securities, LLC	106,000
Natixis Bleichroeder Inc.	106,000
Rodman & Renshaw, LLC	106,000
FIG Partners, LLC	66,250
Total	5,300,000

Sch. 1-1

Annex A-1

[Form of Opinion of Counsel for the Company]

(a) The Registration Statement was declared effective under the Securities Act as of the date and time specified in such opinion; each of the Preliminary Prospectus and the Prospectus was filed with the Commission pursuant to the subparagraph of Rule 424(b) under the Securities Act specified in such opinion on the date specified therein; and based on telephonic conversations with the Commission no order suspending the effectiveness of the Registration Statement has been issued and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or in connection with the offering is pending before the Commission.

(b) The Registration Statement, the Preliminary Prospectus, each Issuer Free Writing Prospectus included in the Pricing Disclosure Package and the Prospectus, including the documents incorporated by reference therein, in each case as of their respective effective or issue dates (other than (i) the financial statements and notes thereto and schedules included or incorporated by reference therein or omitted therefrom, (ii) the summary reserve report of the independent petroleum engineers included or incorporated by reference therein or (iii) the other financial, statistical or reserve engineering data contained therein or omitted therefrom, as to which such counsel expresses no opinion) appeared on their faces to have complied as to form in all material respects with the requirements of the Securities Act or the Exchange Act, as applicable (except that such counsel shall express no opinion as to Regulation S-T).

(c) The Company is validly existing and in good standing under the laws of the State of Texas, and has the corporate power and authority to own its properties and to otherwise carry on its business under the laws of the State of Texas and its Amended and Restated Articles of Incorporation and Second Amended and Restated Bylaws as described in the Registration Statement, Prospectus and Preliminary Prospectus.

(d) The authorized capital stock of the Company consists of (i) 100,000,000 shares of Common Stock and (ii) 10,000,000 shares of preferred stock, par value $.001 per share.

(e) The Company has the corporate power and authority to execute and deliver this Agreement and to perform its obligations hereunder.

(f) The Underwriting Agreement has been duly authorized, executed and delivered by the Company.

(g) The Shares to be issued and sold by the Company hereunder have been duly authorized, and when delivered to and paid for by the Underwriters in accordance with the terms of this Agreement, will be validly issued, fully paid and non-assessable.

(h) The execution and delivery of the Underwriting Agreement by the Company does not and the performance by the Company of its obligations under the Underwriting Agreement (except as contemplated by the Registration Statement, the Pricing Disclosure Package or the Prospectus) will not, (i) whether with or without the giving of notice or passage of time or both, conflict with or constitute a breach of, or default under, or result in the creation of

Annex A-1-

imposition of any lien, charge or encumbrance upon any property or assets of the Company pursuant to any contract, indenture, mortgage, deed of trust, loan or credit agreement, note, lease or any other agreement or instrument filed as an exhibit to the Registration Statement, the Company’s Annual Report on Form 10-K for the year ended December 31, 2008, Quarterly Reports on Form 10-Q for the quarters ended March 31, 2009 and June 30, 2009 or any of the Company’s subsequent Current Reports on Form 8-K (the “Filed Exhibits”), (ii) result in a violation of the Amended and Restated Articles of Incorporation or Second Amended and Restated Bylaws of the Company, (iii) result in the violation of any law, rule or regulation of any Included Law or (iv) result in any violation of any order, writ, judgment or decree of any governmental authority known to such counsel and identified in a schedule to such counsel’s opinion, except in the case of clause (i) as could not reasonably be expected to have a Material Adverse Effect.

(i) No filing with, or authorization, approval, consent, license, order, registration, qualification or decree of, any Federal or state governmental authority or agency is legally required for the due execution and delivery of the Underwriting Agreement by the Company and the performance by the Company of its obligations under the Underwriting Agreement except for (i) those that have been obtained or made, (ii) those required under Federal and state securities laws or blue sky laws and (iii) those that may be required under the rules and regulations of The NASDAQ Global Select Market.

(j) The statements in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the captions “Material U.S. Federal income tax consequences for non-U.S. holders” and “Description of Capital Stock,” in so far as such statements purport to summarize certain provisions of the documents and legal matters referred to therein, fairly summarize such provisions and legal matters in all material respects, subject to the qualifications and assumptions stated therein.

(k) The Company is not an “investment company” within the meaning of the Investment Company Act of 1940, as amended.

Negative Assurance:

Such counsel shall also state that such counsel has participated in conferences with officers and other representatives of the Company, the independent registered public accounting firms and the reserve engineers for the Company, your counsel and your representatives at which the contents of the Registration Statement, the Pricing Disclosure Package and the Prospectus (including the Incorporated Documents) and related matters were discussed and, although such counsel has not independently verified and is not passing upon, and does not assume any responsibility for, the accuracy, completeness or fairness of the statements contained or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus (except as and to the extent set forth in paragraph j above), on the basis of the foregoing (relying with respect to factual matters to the extent we deem appropriate upon statements by officers and other representatives of the Company), such counsel advises you that no information has come to its attention that causes it to believe that (1) the Registration Statement, at the time it became effective and at the date of the Underwriting Agreement, contained an untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (2) the Pricing Disclosure Package, as of the Applicable Time (which such counsel may assume to

Annex A-2-

be the date of the Underwriting Agreement), included an untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading or (3) the Prospectus, at the time the Company’s prospectus supplement was filed with the Commission on September     , 2009 and as of the Closing Date, included or includes an untrue statement of a material fact or omitted or omits to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, it being understood that such counsel shall express no opinion, statement or belief with respect to (i) the historical financial statements and related schedules, including the notes and schedules thereto and the auditor’s report thereon, (ii) any other financial or accounting data, included or incorporated or deemed incorporated by reference in, or excluded from, the Registration Statement, the Pricing Disclosure Package or the Prospectus, (iii) representations and warranties and other statements of fact included in the Filed Exhibits, (iv) any oil and natural gas reserve information in the Registration Statement, the Pricing Disclosure Package or the Prospectus and (v) the exclusion from the Preliminary Prospectus of any pricing information (and directly related disclosure) included in the Prospectus.

Such opinion shall be limited to the law of the State of Texas and the Federal securities law of the United States.

In rendering such opinion, such counsel may rely as to matters of fact on certificates of responsible officers of the Company and public officials that are furnished to the Underwriters.

The opinion of Jackson Walker L.L.P. described above shall be rendered to the Underwriters at the request of the Company and shall so state therein.

Annex A-3-

Annex B

a. Pricing Disclosure Package

Free Writing Prospectus dated September 23, 2009.

Annex B-1

Annex C

Pricing Term Sheet dated as of September 23, 2009 Issuer Free Writing Prospectus dated September 23, 2009 Relating to Preliminary Prospectus Supplement Dated September 22, 2009 Filed Pursuant to Rule 433 Registration Statement No. 333-159614

5,300,000 Shares of Common Stock

This term sheet to the preliminary prospectus supplement dated September 23, 2009 should be read together with the preliminary prospectus supplement dated September 22, 2009, and the accompanying prospectus dated June 10, 2009, before making a decision in connection with an investment in the securities. The information in this term sheet updates and supersedes the information in the preliminary prospectus supplement to the extent that it is inconsistent therewith, or prepared based on assumptions that are inconsistent with the information below.

Issuer:	ATP OIL & GAS CORPORATION
Title of securities	Common stock, par value $0.001 per share, of the Issuer
Common stock offered by us in this offering:	5,300,000 shares (or a total of 6,095,000 shares if the underwriters exercise in full their option to purchase up to 795,000 additional shares of the Issuer’s common stock)
	Per Share	Total
Public offering price:	$18.50	$	98,050,000.00
Underwriting discount:	$0.8325	$	4,412,250.00
Proceeds to us (before expenses)	$17.6675	$	93,637,750.00
Common stock outstanding after the offering:	50,082,670 shares (or 50,877,670 shares if the underwriters exercise in full their option to purchase up to 795,000 additional shares of the Issuer’s common stock), excluding between 5,630,625 and 8,648,649 shares that may be issued in connection with the conversion of the Convertible Preferred Stock, as described below.
Trade Date:	September 23, 2009
Settlement Date:	September 29, 2009 (T+4)
Underwriters:	J.P. Morgan Securities Inc. Credit Suisse Securities (USA) LLC Canaccord Adams Inc. Pritchard Capital Partners, LLC. SMH Capital, Inc. Howard Weil Incorporated Johnson Rice & Company L.L.C. Wunderlich Securities, Inc. C. K. Cooper & Company, Inc. Global Hunter Securities, LLC Natixis Bleichroeder Inc. Rodman & Renshaw, LLC FIG Partners, LLC
Concurrent Preferred Stock Offering:	Concurrently with this offering, the Issuer also offered 1,250,000 shares of the Issuer’s 8.00% Convertible Perpetual Preferred Stock (1,600,000 shares if the initial purchasers exercise their over-allotment option in full). The conversion rate will initially be 4.5045 shares of the Issuer’s Common Stock for each share of Convertible Preferred Stock.
Additional Information:	In addition to the pricing information set forth above, the “estimated net proceeds”, as referred to throughout the preliminary prospectus supplement, will be updated to be $93.4 million and the “Capitalization” section of the preliminary prospectus supplement will be updated to reflect the following changes ($             in thousands):
	•       As Adjusted Cash and Cash Equivalents			$	260,981
	•       As Adjusted Preferred Stock			$	1,259,597
	•       As Adjusted Additional paid in capital			$	562,192
	•       As Adjusted Total shareholders’ equity			$	623,873
	•       As Adjusted Total Equity			$	763,482
	•       As Adjusted Total Capitalization			$	2,023,079

The issuer has filed a registration statement (including a prospectus) with the Securities and Exchange Commission (the “SEC”) for the offering to which this communication relates. Before you invest, you should read the prospectus in that registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer and this offering. You may get these documents for free by visiting IDEA on the SEC Web site at www.sec.gov. Alternatively, the issuer, any underwriter or any dealer participating in the offering will arrange to send you the prospectus if you request it by contacting J.P. Morgan Securities Inc. at 4 Chase Metrotech Center, CS Level, Brooklyn, NY 11245, Attn: Chase Distribution and Support Service, Northeast Statement Processing, or by telephone to (718) 242-8002, or by fax at (718) 242-8003, or Credit Suisse Securities (USA) LLC at One Madison Avenue, New York, NY 10010, Attn: Credit Suisse Prospectus Department, or by telephone to (800) 221-1037.

Annex C-1

Exhibit A

FORM OF LOCK-UP AGREEMENT

[                    ], 2009

J.P. Morgan Securities Inc.

Credit Suisse Securities (USA) LLC

As Representatives of the

several Common Stock Underwriters

listed in Schedule 1 to the Common

Stock Underwriting Agreement

referred to below

c/o J.P. Morgan Securities Inc.

383 Madison Avenue

New York, New York 10179

Credit Suisse Securities (USA) LLC

J.P. Morgan Securities Inc.

As Representatives of the

several Preferred Stock Initial

Purchasers listed in Schedule A

to the Preferred Stock Purchase

Agreement referred to below

c/o Credit Suisse Securities (USA) LLC

11 Madison Avenue

New York, New York 10010

Re: ATP Oil & Gas Corporation — Public Offering

Ladies and Gentlemen:

The undersigned understands that you, as (1) Representatives of the several Underwriters, propose to enter into an Underwriting Agreement (the “Underwriting Agreement”) with ATP Oil & Gas Corporation, a Texas corporation (the “Company”), providing for the public offering (the “Public Offering”) by the several Underwriters named in Schedule 1 to the Underwriting Agreement (the “Underwriters”), of Common Stock, $0.001 per share par value, of the Company (the “Common Stock”) and (2) Representatives of the several Initial Purchasers, propose to enter into a Purchase Agreement (the “Purchase Agreement”) with the Company, providing for the private placement (the “Private Placement”) by the Initial Purchasers named in Schedule A to the Purchase Agreement (the “Initial Purchasers”) of the Company’s 8.00% Convertible Perpetual Preferred Stock (the “Preferred Stock”). Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Underwriting Agreement or the Purchase Agreement, as applicable.

Exhibit A-1

In consideration of the Underwriters’ agreement to purchase and make the Public Offering of the Common Stock and of the Initial Purchasers’ agreement to purchase and consummate the Private Placement of the Preferred Stock, and for other good and valuable consideration receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of the Representatives, on behalf of the Underwriters and the Initial Purchasers, the undersigned will not, during the period ending 90 days after the date of the prospectus relating to the Public Offering (the “Prospectus”) and the offering circular relating to the Private Placement (the “Offering Circular”), (1) offer, pledge, announce the intention to sell, 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, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (including without limitation, Common Stock which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of a stock option or warrant) or (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, 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 or (3) 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 without the prior written consent of the Representatives, in each case other than (A) transfers of shares of Common Stock (i) as a bona fide gift or gifts, (ii) by will or intestate succession or (iii) to a trust the beneficiaries of which are the undersigned or member or members of the undersigned’s immediate family (a “Trust”), and (B) distributions of shares of Common Stock to members or stockholders of the undersigned; provided that in the case of any transfer or distribution pursuant to clause (B), each donee or distributee shall execute and deliver to the Representatives a lock-up letter in the form of this paragraph; and provided, further, that in the case of any transfer or distribution pursuant to clause (B), no filing by any party (donor, donee, transferor or transferee) under the Securities Exchange Act of 1934, as amended, or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on a Form 5 made after the expiration of the 90-day period referred to above). In addition, the undersigned agrees that, without the prior written consent of the Representatives on behalf of the Underwriters and the Initial Purchasers, it will not, during the period ending 90 days after the date of the Prospectus and the Offering Circular, 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. Notwithstanding the foregoing, if (1) during the last 17 days of the 90-day restricted period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (2) prior to the expiration of the 90-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 90-day period, the restrictions imposed by this Letter Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

The restrictions set forth herein will not apply to aggregate sales or other dispositions of Common Stock, not in excess of 500,000 shares of Common Stock by the undersigned together with all other persons executing a similar letter pursuant to Section 6(m) of the Underwriting Agreement and Section 7(g) of the Purchase Agreement (“Participating Persons”), and

Exhibit A-2

their respective immediate family members, Trusts and affiliates. Prior to any proposed sale or other disposition by any Participating Person, or their respective immediate family members, Trusts and affiliates, pursuant to the exception set forth in the immediately preceding sentence, such Participating Person, both for itself and on behalf of their immediate respective family members, Trusts and affiliates, shall notify the Company and the Representatives of such proposed sale or other disposition at least three trading days prior to the proposed date thereof and such Participating Person, its respective family member, Trust or affiliate shall consummate such sale or other disposition only upon receipt of written confirmation from the Company and the Representatives that such sale or other disposition will not, when taken together with all other sales and other dispositions by all Participating Persons or their immediate respective family members, Trusts and affiliates pursuant to such exception, exceed 500,000 shares of Common Stock.

In furtherance of the foregoing, the Company, and any duly appointed transfer agent for the registration or transfer of the securities described herein, are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Letter Agreement.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Letter Agreement. All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

The undersigned understands that, if the Underwriting Agreement and the Purchase Agreement does not become effective, or if the Underwriting Agreement and the Purchase Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the Common Stock or the Preferred Stock to be sold thereunder, the undersigned shall be released from, all obligations under this Letter Agreement. The undersigned understands that the Underwriters are entering into the Underwriting Agreement and proceeding with the Public Offering in reliance upon this Letter Agreement and that the Initial Purchasers are entering into the Purchase Agreement and proceeding with the Private Placement in reliance upon this Letter Agreement.

Exhibit A-3

This Letter Agreement shall be governed by and construed in accordance with the laws of the State of New York, without regard to the conflict of laws principles thereof.

Very truly yours,

[NAME OF STOCKHOLDER]

By:

Name:

Title:

Exhibit A-4

Exhibit B

FORM OF

ATP OIL & GAS CORPORATION

CHIEF FINANCIAL OFFICER’S CERTIFICATE

I, Albert L. Reese Jr., do hereby certify that I am the Chief Financial Officer of ATP Oil & Gas Corporation, a Texas corporation (the “Company”), and, in my capacity as Chief Financial Officer, and based upon an examination of the Company’s financial records and schedules undertaken by myself or members of my staff who are responsible for the Company’s financial and accounting matters, do hereby certify that:

1. I am providing this certificate in connection with the marketing of (1) 5,300,000 shares of the Company’s common stock, as described in that certain prospectus supplement, dated September 23, 2009 (the “Prospectus Supplement”), to the prospectus dated June 10, 2009 (the “Prospectus”) and (2) 1,250,000 shares of the Company’s 8.00% convertible perpetual preferred stock, as described in that certain confidential offering circular (the “Offering Circular”), dated September 23, 2009.

2. I am familiar with the accounting, operations and records systems of the Company;

3. I have read the (1) the Prospectus Supplement, (2) the Prospectus, (3) the Offering Circular, (4) the Annual Report on Form 10-K for the year ended December 31, 2008, (5) the Quarterly Report on Form 10-Q for the quarter ended March 31, 2009 and (6) The Quarterly Report on Form 10-Q for the quarter ended June 30, 2009.

4. No consolidated financial statements of the Company as of any date for any period subsequent to June 30, 2009 are currently available;

5. I have no reason to believe that for the period from July 1, 2009 to August 31, 2009, there were any decreases, as compared with the corresponding period in the preceding year, in consolidated net sales or in the total or per-share amounts of income before extraordinary items or of net income, except in all instances for changes, increases or decreases that the Prospectus Supplement, the Prospectus and the Offering Circular disclose have occurred or may occur;

6. I have supervised the compilation of and reviewed the circled information contained on the attached Exhibit A, which is included or incorporated by reference into the Prospectus Supplement and the Offering Circular. I have performed the following procedures with respect to the circled information identified on Exhibit A, which were applied as indicated with respect to the capital letters as explained below, and, to my knowledge, such information is correct, complete and accurate in all material respects:

a. Recomputed and/or compared to corresponding amounts appearing in the accounting records of the Company and found the amounts (as adjusted for rounding, where appropriate) to be in agreement.

Exhibit B-1

b. Compared and agreed (as adjusted for rounding, where appropriate), or recalculated and agreed (as adjusted for rounding, where appropriate), to a schedule derived from the Company’s accounting records, and compared the amounts on the schedule to corresponding amounts appearing in the accounting records and found the amounts to be in agreement (as adjusted for rounding, where appropriate) and determined that the amounts on the schedule were arithmetically correct.

c. Proved the arithmetic accuracy of the percentages and ratios (as adjusted for rounding, where applicable) based on data in the above-mentioned accounting records and schedules.

7. Attached as Exhibit B, are pages 24 and 27 of the Quarterly Report referenced in item 3(6) above. The circled amount on page 24 is incorrect and the correct amount is $3.0, and the circled amount on page 27 is incorrect and the correct amount is $37,572.

In witness whereof this certificate has been executed and delivered by the chief financial officer of the Company on this      day of September, 2009.

Albert L. Reese, Jr.

Chief Financial Officer

Exhibit A-2

EX-3.1

Exhibit 3.1

STATEMENT OF RESOLUTIONS ESTABLISHING THE

8% CONVERTIBLE PERPETUAL PREFERRED STOCK

OF

ATP OIL & GAS CORPORATION

Pursuant to Article 2.13 of the Texas Business Corporation Act, ATP Oil & Gas Corporation, a Texas corporation (the “Corporation”), hereby submits the following statement for the purpose of establishing and designating a series of shares and fixing and determining the relative rights and preferences thereof:

1. The name of the Corporation is ATP Oil & Gas Corporation.

2. The following resolutions, establishing and designating a series of shares and fixing and determining the relative rights and preferences thereof, was duly adopted by the Board of Directors of the Corporation (the “Board of Directors”) as of September 28, 2009:

BE IT RESOLVED, that pursuant to the Restated Articles of Incorporation of the Corporation authorizing the Board of Directors to establish and designate series of the preferred stock, $0.001 par value, of the Corporation (the “Preferred Stock”) and to fix and determine the relative rights and preferences of the shares of any such series, the Corporation hereby provides for the issuance of a series of the Preferred Stock designated as “8% Convertible Perpetual Preferred Stock” (the “Convertible Preferred Stock”), which shall have the following terms:

A. NUMBER OF SHARES. The maximum number of shares of Convertible Preferred Stock shall be One Million Six Hundred Thousand (1,600,000).

B. DEFINITIONS. As used in this resolution (this “Designating Resolution”), the following words and phrases shall have the respective meanings set forth in this paragraph B:

“Additional Shares” shall have the meaning set forth in paragraph I.1.

“Agent Members” shall have the meaning set forth in paragraph O.2(b).

“Business Day” means each day other than a Saturday, a Sunday or a day on which banking institutions are not required to be open in the State of New York.

“Certified Convertible Preferred Stock” shall have the meaning set forth in paragraph O.2(c).

“Commission” means the United States Securities and Exchange Commission.

“Conversion Date” shall have the meaning set forth in paragraph G.2.

“Conversion Rate” means 4.5045 shares of the Corporation’s common stock per share of Convertible Preferred Stock, subject to adjustment as set forth in paragraph G.4.

“Conversion Price” shall mean the amount determined by dividing the Liquidation Preference by the Conversion Rate at such time.

“Current Market Price” means the average of the Daily Closing Price per share of the Corporation’s common stock on each of the five consecutive Trading Days preceding the earlier of the day preceding the date in question and the day before the Ex-Date with respect to the issuance or distribution requiring such computation; provided, however, that solely for purposes

of determining any adjustment to the Conversion Rate in the event of a Spin-Off (as contemplated by paragraph G.4(d)), the “Current Market Price” means the average of the Daily Closing Price per share of the Corporation’s common stock on each of the first ten consecutive Trading Days commencing on and including the fifth Trading Day following the Ex-Date for such distribution.

“Daily Closing Price” of the Corporation’s common stock on any date means the closing sale price per share (or if no closing sale price is reported, the average of the closing bid and ask prices or, if more than one in either case, the average of the average closing bid and the average closing ask prices) on such date as reported on the principal United States securities exchange on which the Corporation’s common stock is traded or, if the Corporation’s common stock is not listed on a United States national or regional securities exchange, as reported by Pink Sheets LLC. In the absence of such a quotation, the Daily Closing Price shall be an amount determined in good faith by the board of directors of the Corporation, or a committee thereof, to be the fair value of the Corporation’s common stock.

“Daily VWAP” means, with respect to the Corporations’ common stock on any Trading Day, the per share volume-weighted average price of the Corporation’s common stock as displayed under the heading “Bloomberg VWAP” on Bloomberg page ATPG <EQUITY> VAP (or its equivalent successor if such page is not available) in respect of the period from 9:30 a.m. to 4:00 p.m., New York City time, on such Trading Day (or if such volume-weighted average price is unavailable, the market value of one share of the Corporation’s common stock on such Trading Day determined, using a volume-weighted average method to the extent practicable, by a nationally recognized independent investment banking firm retained for this purpose by the Corporation), which shall be determined without regard to after-hours trading or any other trading outside of the regular trading session.

“Dividend Agent” shall have the meaning set forth in paragraph E.4.

“Dividend Payment Date” means January 1, April 1, July 1 and October 1 of each year, commencing January 1, 2010.

“Dividend Period” means the period commencing on and including a Dividend Payment Date and ending on and including the day immediately preceding the next succeeding Dividend Payment Date, with the exception that the first Dividend Period shall commence on and include the Issue Date and end on and include December 31, 2009.

“Dividend Rate” means the rate per annum of 8% per share on the Liquidation Preference.

“DTC” shall have the meaning set forth in paragraph O.1(b).

“Ex-Date” means, when used with respect to any issuance or distribution requiring computation of the Current Market Price, the first date on which shares of the Corporation’s common stock trade without the right to receive such issuance or distribution.

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

“Expiration Date” shall have the meaning set forth in paragraph H.1.

2

“Fundamental Change” means the occurrence of any of the following:

(i) the Corporation consolidates with, or merges with or into, another person, or any person consolidates with, or merges with or into, the Corporation, other than pursuant to a transaction in which the persons that “beneficially owned” (as defined in Rule 13d-3 under the Exchange Act) directly or indirectly, the voting shares of the Corporation immediately prior to such transaction beneficially own, directly or indirectly, voting shares representing a majority of the total voting power of all outstanding classes of voting shares of the continuing or surviving person in substantially the same proportion among themselves as such ownership immediately prior to such transaction; provided, however, a Fundamental Change shall not be deemed to have occurred in the case of a merger or consolidation if at least 90% of the consideration (excluding cash payments for fractional shares and cash payments pursuant to dissenters’ appraisal rights) in the merger or consolidation consists of common stock of a company incorporated or organized under the laws of the United States or any political subdivision thereof, and traded on The Nasdaq Global Select Market or the New York Stock Exchange (or which will be so traded or quoted when issued or exchanged in connection with such transaction);

(ii) the sale, lease or transfer, in one or a series of related transactions, of all or substantially all of the Corporation’s assets (determined on a consolidated basis) to any person or group (as such term is used in Section 13(d)(3) of the Exchange Act), other than pursuant to a transaction, in which persons that “beneficially owned” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, the voting shares immediately prior to such transaction beneficially own, directly or indirectly, voting shares representing a majority of the total voting power of such person or group;

(iii) the adoption of a plan the consummation of which would result in the liquidation or dissolution of the Corporation;

(iv) the acquisition, directly or indirectly, by any “person” or “group” (as such term is used in Section 13(d)(3) of the Exchange Act), of beneficial ownership (as defined in Rule 13d-3 under the Exchange Act) of more than 50% of the aggregate voting power of the Corporation’s voting shares;

(v) during any period of two consecutive years, individuals who at the beginning of such period comprised the Corporation’s board of directors (together with any new directors whose appointment by such board of directors or whose nomination for election by the Corporation’s shareholders was approved by a vote of 66% of the Corporation’s directors then still in office who were either directors at the beginning of such period or whose election or nomination for election was previously so approved) cease for any reason to constitute a majority of the Corporation’s board of directors then in office; or

(vi) the Corporation’s common stock ceases to be listed on The Nasdaq Global Select Market or the New York Stock Exchange.

“Fundamental Change Conversion Period” shall have the meaning set forth in paragraph H.1.

“Fundamental Change Effective Date” means, with respect to the occurrence of any Fundamental Change, the date on which such Fundamental Change occurs.

“Fundamental Change Notice” shall have the meaning set forth in paragraph H.3.

“Fundamental Change Stock Price” means, with respect to a Fundamental Change, (i) if holders of the Corporation’s common stock receive only cash in the Fundamental Change transaction, the cash amount paid per share of the Corporation’s common stock or (ii) if not, the average of the Daily Closing Price per share of the Corporation’s common stock on the five Trading Days prior to but not including the Fundamental Change Effective Date.

3

“Global Convertible Preferred Stock” shall have the meaning set forth in paragraph O.2(a).

“Indemnified Parties” shall have the meaning set forth in paragraph N.4(a).

“Issue Date” means September 29, 2009.

“Junior Stock” means all classes of the Corporation’s common stock and any other class of capital stock or series of preferred stock of the Corporation established after the Issue Date, the terms of which do not expressly provide that such class or series ranks senior to or on a parity with the Convertible Preferred Stock as to dividend rights or rights upon the Corporation’s liquidation, winding-up or dissolution.

“Liquidation Preference” means, with respect to each share of Convertible Preferred Stock, $100.

“Mandatory Conversion” shall have the meaning set forth in paragraph J.1.

“Mandatory Conversion Date” shall have the meaning set forth in paragraph J.2.

“Make-Whole Premium” shall have the meaning set forth in paragraph I.1.

“Managing Underwriters” shall have the meaning set forth in paragraph N.5.

“Market Disruption Event” means (i) a failure by The Nasdaq Global Select Market or, if the Corporation’s common stock is not listed on The Nasdaq Global Select Market, the principal U.S. national or regional securities exchange on which the Corporation’s common stock is listed, to open for trading during its regular trading session or (ii) the occurrence or existence prior to 1:00 p.m. on any trading day for the Corporation’s common stock of an aggregate one half hour period of any suspension or limitation imposed on trading (by reason of movements in price exceeding limits permitted by the stock exchange or otherwise) in the Corporation’s common stock or in any options, contracts or future contracts relating to the Corporation’s common stock.

“Officer” means the Chairman of the Board of Directors of the Corporation, the Chief Executive Officer, the President, any Vice President, the Treasurer, the Secretary or any Assistant Secretary of the Corporation.

“Parity Stock” means any class of capital stock or series of preferred stock of the Corporation established after the Issue Date, the terms of which expressly provide that such class or series shall rank on a parity with the Convertible Preferred Stock as to dividend rights or rights upon the Corporation’s liquidation, winding-up or dissolution.

“Publicly Traded Common Stock” means shares of common stock that are listed on any of the New York Stock Exchange, the Nasdaq Global Select Market, the Nasdaq Global Market or any of their respective successors, or will be so listed when issued or exchanged with the relevant Fundamental Change.

“Record Date” means (i) with respect to the dividends payable on January 1, April 1, July 1 and October 1 of each year, the immediately preceding December 15, March 15, June 15 and September 15, respectively, and (ii) with respect to matters other than the payment of dividends, such record date established by the Corporation’s board of directors pursuant to Article 2.26 of the Texas Business Corporation Act (or any successor provision thereto).

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“Registrable Securities” means shares of the Corporation’s common stock issued in payment as dividends in respect of the first five dividend payments on the Convertible Preferred Stock until, for each such share, the earliest of (i) the date on which such share has been effectively registered under the Securities Act and disposed of in accordance with the Shelf Registration Statement or (ii) the date on which such share becomes freely transferable by holders thereof that are not affiliates of the Corporation without registration under the Securities Act.

“Reorganization Event” shall have the meaning set forth in paragraph G.8.

“Scheduled Trading Day” means any day that is scheduled to be a Trading Day; provided, however, that if the Corporation’s common stock is not listed for trading or quotation on or by any exchange or quotation system, then “Scheduled Trading Day” means a Business Day.

“Senior Stock” means any class of capital stock or series of preferred stock of the Corporation established after the Issue Date, the terms of which expressly provide that such class or series shall rank senior to the Convertible Preferred Stock as to dividend rights or rights upon the Corporation’s liquidation, winding-up or dissolution.

“Shelf Registration” shall have the meaning set forth in paragraph N.1(a)(i).

“Shelf Registration Statement” shall have the meaning set forth in paragraph N.1(a)(i).

“Spin-Off” shall have the meaning set forth in paragraph G.4.

“Subsidiary” means any subsidiary of the Corporation.

“Suspension Period” shall have the meaning set forth in paragraph N.2(l).

“Transfer Agent” means the American Stock Transfer and Trust Company, LLC, until a successor replaces it and, thereafter, means the successor.

“Trading Day” means a day during which (i) trading in the Corporation’s common stock generally occurs on The Nasdaq Global Select Market or, if the Corporation’s common stock is not listed on The Nasdaq Global Select Market, or the principal United States national or regional securities exchange on which the Corporation’s common stock is then listed or, if the Corporation’s common stock is not so listed, admitted for trading or quote, any Business Day and (ii) there is no Market Disruption Event; provided, however, that a “Trading Day” only includes those days that have a scheduled closing time of 4:00 p.m. (New York City time) or the then standard closing time for regular trading on the relevant exchange or trading system.

“Voting Rights Class” shall have the meaning set forth in paragraph M.2.

C. RANK. The Convertible Preferred Stock shall, with respect to dividend rights or rights upon the Corporation’s liquidation, winding-up or dissolution, rank: (i) senior to any Junior Stock; (ii) on a parity, in all respects, with any Parity Stock; and (iii) junior to any Senior Stock.

D. DIVIDENDS.

1. Holders of shares of Convertible Preferred Stock shall be entitled to receive, when, as and if declared by the Corporation’s board of directors out of funds of the Corporation legally available for payment, cumulative dividends at the Dividend Rate, payable in cash, by delivery of shares of the Corporation’s common stock or through any combination of cash and shares of the Corporation’s

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common stock, as provided pursuant to paragraph E. Dividends on the Convertible Preferred Stock shall be payable quarterly on each Dividend Payment Date at the Dividend Rate, and shall accumulate from the most recent date as to which dividends shall have been paid or, if no dividends have been paid, from the Issue Date, whether or not in any Dividend Period(s) there have been funds legally available for the payment of such dividends. Dividends shall be payable to holders of record as they appear on the Corporation’s stock register on the immediately preceding Record Date. Accumulations of dividends on shares of Convertible Preferred Stock do not bear interest.

2. Dividends payable on the Convertible Preferred Stock for any period other than a full Dividend Period (based upon the number of days elapsed during the period) are computed on the basis of a 360-day year consisting of twelve 30-day months.

3. No dividend shall be declared or paid upon, or any sum set apart for the payment of dividends upon, any outstanding share of Convertible Preferred Stock with respect to any Dividend Period unless all dividends for all preceding Dividend Periods have been declared and paid or declared and a sufficient sum or number of shares of the Corporation’s common stock have been set apart for the payment of such dividend, upon all outstanding shares of Convertible Preferred Stock.

4. Unless all accrued, cumulated and unpaid dividends on the Convertible Preferred Stock for all past Dividend Periods shall have been paid in full, the Corporation shall not:

(a) declare or pay any dividend or make any distribution of assets on any Junior Stock, other than dividends or distributions in the form of Junior Stock and cash solely in lieu of fractional shares in connection with any such dividend or distribution;

(b) redeem, purchase or otherwise acquire any shares of Junior Stock or pay or make any monies available for a sinking fund for such shares of Junior Stock, other than (i) upon conversion or exchange for other Junior Stock or (ii) the purchase of fractional interests in shares of any Junior Stock pursuant to the conversion or exchange provisions of such shares of Junior Stock;

(c) declare or pay any dividend or make any distribution of assets on any shares of Parity Stock, other than dividends or distributions in the form of Parity Stock or Junior Stock and cash solely in lieu of fractional shares in connection with any such dividend or distribution; or

(d) redeem, purchase or otherwise acquire any shares of Parity Stock, except upon conversion into or exchange for other Parity Stock or Junior Stock and cash solely in lieu of fractional shares in connection with any such conversion or exchange.

5. When dividends are not paid in full upon the shares of Convertible Preferred Stock, as discussed above, all dividends declared on the Convertible Preferred Stock and any other Parity Stock shall be paid either (a) pro rata so that the amount of dividends so declared on the shares of Convertible Preferred Stock and each such other class or series of Parity Stock shall in all cases bear to each other the same ratio as accumulated dividends on the shares of Convertible Preferred Stock and such class or series of Parity Stock bear to each other or (b) on another basis that is at least as favorable to the holders of the Convertible Preferred Stock entitled to receive such dividends.

E. METHOD OF PAYMENT OF DIVIDENDS.

1. The Corporation shall pay any dividend on the Convertible Preferred Stock (whether or not for a current Dividend Period or any prior Dividend Period, and including in connection with the payment of accrued accumulated and unpaid dividends upon conversion of the Convertible Preferred Stock as discussed in this Statement of Resolutions), either: (a) in cash; (b) by delivery of shares of the Corporation’s common stock; or (c) through any combination of cash and shares of the Corporation’s common stock.

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2. If the Corporation makes any payment of dividends on the Convertible Preferred Stock in shares of the Corporation’s common stock, such shares of the Corporation’s common stock shall be valued for such purpose, in the case of any dividend payment, at 95% of the average of the Daily VWAP of the Corporation’s common stock on each of the ten consecutive Trading Days ending on the second Trading Day immediately preceding the payment date for such dividend.

3. The Corporation shall give the holders of the Convertible Preferred Stock notice of the payment method in respect of any dividend at least 20 Scheduled Trading Days prior to the payment date for such dividend.

4. If the Corporation elects to pay all or a portion of a dividend on the Convertible Preferred Stock in the form of shares of the Corporation’s common stock, the Corporation shall deliver such shares to the Transfer Agent or another agent (in such capacity, the “Dividend Agent”) on behalf of the holders of the Convertible Preferred Stock and shall instruct, at the Corporation’s sole option, the Dividend Agent to either:

(a) sell such shares for cash on behalf of the holders of the Convertible Preferred Stock and deliver the net proceeds to the holders less any deductions for withholding taxes; or

(b) deliver such shares to or for the account of the holders less any shares required to be sold for withholding taxes.

5. If the Corporation pays all or a portion of a dividend in the form of shares of the Corporation’s common stock, any such shares of the Corporation’s common stock delivered to the Dividend Agent shall be owned beneficially by the holders of the Convertible Preferred Stock upon delivery to the Dividend Agent, and the Dividend Agent shall hold such shares and any net cash proceeds from the sale of such shares for the exclusive benefit of the holders.

6. If the Corporation elects to deliver shares to the Dividend Agent on behalf of the holders of the Convertible Preferred Stock for sale for cash on behalf of such holders, the Dividend Agent shall serve as the designated agent of the holders of the Convertible Preferred Stock in making such sales. By purchasing and or acquiring the Convertible Preferred Stock, each holder of Convertible Preferred Stock is deemed to appoint the Dividend Agent as such holder’s agent for the sale of any shares of the Corporation’s common stock that are delivered to the Dividend Agent, on such holder’s behalf, upon payment of dividends on the Convertible Preferred Stock.

7. The net proceeds of any sales of shares of the Corporation’s common stock delivered to the Dividend Agent as dividend payments shall be distributed to holders of Convertible Preferred Stock on a pro rata basis based on the aggregate Liquidation Preference of the outstanding shares of Convertible Preferred Stock less any deductions for withholding taxes as determined on a holder-by-holder basis.

8. In order to satisfy any obligation to withhold taxes arising from any payment of a dividend or deemed dividend with respect to the Convertible Preferred Stock, by purchasing and or acquiring the Convertible Preferred Stock, each holder of the Convertible Preferred Stock is deemed to authorize the Corporation and the Dividend Agent to make any deductions required by law, and pay to any taxing authority any amount necessary to satisfy such obligation, including the payment of any portion or all of the net cash proceeds resulting from the sale of shares of common stock that are owned beneficially by such holder of the Convertible Preferred Stock.

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9. If a record holder of Convertible Preferred Stock gives notice to the Dividend Agent at least 10 days prior to the applicable Dividend Payment Date not to sell shares of the Corporation’s common stock to be delivered as dividend payment to the Dividend Agent and held on behalf of such holder, the Dividend Agent shall deliver to or for the account of such holder, promptly after receipt by the Dividend Agent, the shares of the Corporation’s common stock issued in payment of such dividend except any shares required to be deducted on account of withholding taxes.

10. If the Corporation elects (i) to deliver shares of the Corporation’s common stock to the Dividend Agent to sell such shares for cash on behalf of the holders of the Convertible Preferred Stock and a holder gives notice (as described above) of its election to receive such shares and not to have them sold on such holder’s behalf or (ii) to cause the Dividend Agent to deliver shares of the Corporation’s common stock to holders of Convertible Preferred Stock, such shares shall be treated as restricted securities, bear a legend to that effect and not be transferable by the recipient thereof except pursuant to an effective registration statement or pursuant to an exemption from the registration requirements of the Securities Act. The Corporation’s obligation to register any such shares on behalf of holders of Convertible Preferred Stock is limited to those obligations set forth in paragraph N. In addition, each holder must comply with the requirements set forth in paragraph N.

11. In lieu of issuing fractional shares of the Corporation’s common stock, the Corporation will pay a cash adjustment to each holder of Convertible Preferred Stock entitled to a fraction of a share of the Corporation’s common stock, provided, however, that the Corporation may round such fractional share up to the next highest whole number of shares in lieu of making such cash adjustment.

F. LIQUIDATION PREFERENCE. In the event of any voluntary or involuntary liquidation, winding-up or dissolution of the Corporation, each holder of Convertible Preferred Stock shall be entitled to receive and to be paid out of the Corporation’s assets available for distribution to the Corporation’s shareholders, before any payment or distribution is made to holders of Junior Stock, the Liquidation Preference per share of the Convertible Preferred Stock held by such holder, plus accumulated and unpaid dividends on the shares to the date fixed for liquidation, winding-up or dissolution. If, upon the Corporation’s voluntary or involuntary liquidation, winding-up or dissolution, the amounts payable with respect to the Convertible Preferred Stock and all Parity Stock are not paid in full, the holders of the Convertible Preferred Stock and the Parity Stock shall share equally and ratably in any distribution of the Corporation’s assets available for distribution to the Corporation’s shareholders in proportion to the full liquidation preference and accumulated and unpaid dividends to which they are entitled. After payment of the full amount of the Liquidation Preference and accrued and unpaid dividends to which they are entitled, the holders of the Convertible Preferred Stock shall have no right or claim to any of the Corporation’s remaining assets. For purposes of this paragraph F, neither the sale of all or substantially all of the Corporation’s assets or business (other than in connection with the liquidation, winding-up or dissolution of the Corporation), nor the merger or consolidation of the Corporation into or with any other person, shall be deemed to be a voluntary or involuntary liquidation, winding-up or dissolution of the Corporation.

G. CONVERSION AT THE OPTION OF THE HOLDER; ANTI-DILUTION ADJUSTMENTS.

1. Other than during a Fundamental Change Conversion Period, each holder of the Convertible Preferred Stock shall have the right, at any time, at such holder’s option, to convert, subject to the terms and provisions of this paragraph G, any or all of such holder’s shares of Convertible Preferred Stock into fully paid and nonassessable shares of the Corporation’s common stock at the then applicable Conversion Rate.

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2. In addition to the number of shares of the Corporation’s common stock issuable upon conversion of each share of Convertible Preferred Stock at the option of the holder on the effective date of any conversion (herein referred to as the “Conversion Date”), each converting holder shall have the right to receive, in accordance with the provisions of paragraph D and paragraph E, an amount equal to all accrued, cumulated and unpaid dividends on such converted shares of Convertible Preferred Stock, whether or not declared prior to the Conversion Date, for all prior Dividend Periods ending on or prior to the Dividend Payment Date immediately preceding the Conversion Date (other than previously declared dividends on the Convertible Preferred Stock payable to holders of record as of a prior date), provided that the Corporation is then legally permitted to pay such dividends. Except as described above and in paragraph H, upon any optional conversion of the Convertible Preferred Stock, the Corporation shall make no payment or allowance for unpaid dividends on the Convertible Preferred Stock.

3. Immediately prior to the close of business on the Conversion Date with respect to a conversion, a converting holder of Convertible Preferred Stock shall be deemed to be the holder of record of the shares of the Corporation’s common stock issuable upon conversion of such holder’s Convertible Preferred Stock notwithstanding that the share register of the Corporation shall then be closed or that certificates representing such shares of the Corporation’s common stock shall not then be actually delivered to such holder; provided, however, that prior to the close of business on the applicable Conversion Date, the shares of the Corporation’s common stock issuable upon conversion of the Convertible Preferred Stock shall not be deemed to be outstanding for any purpose and such holder shall have no rights with respect to such shares of the Corporation’s common stock, including voting rights, rights to respond to tender offers and rights to receive any dividends or other distributions on such common stock, by virtue of holding the Convertible Preferred Stock.

4. The Conversion Rate shall be adjusted if:

(a) the Corporation pays a dividend (or other distribution) in shares of the Corporation’s common stock to all holders of shares of the Corporation’s common stock, in which case the Conversion Rate in effect immediately following the Record Date for such dividend (or distribution) shall be multiplied by the following fraction:

    OS₁

OS₀

where

OS₀  = the number of shares of the Corporation’s common stock outstanding immediately prior to the Record Date for such dividend (or distribution); and

OS₁  = the sum of (A) the number of shares of the Corporation’s common stock outstanding immediately prior to the Record Date for such dividend (or distribution) and (B) the total number of shares of the Corporation’s common stock constituting such dividend (or distribution).

(b) the Corporation issues to all holders of the Corporation’s common stock rights or warrants (other than rights or warrants issued pursuant to a dividend reinvestment plan or share purchase plan or other similar plans) entitling them, for a period of up to 45 days from the date of issuance of such rights or warrants, to subscribe for or purchase shares of the Corporation’s common stock at less than the Current Market Price of the Corporation’s common stock on the date fixed for determination of shareholders entitled to receive such rights or warrants, in which case the Conversion

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Rate in effect immediately following the close of business on the Ex-Date for such issuance shall be multiplied by the following fraction:

    OS₀+ X    

OS₀+ Y

where

OS₀  = the number of shares of the Corporation’s common stock outstanding at the close of business on the Record Date for such issuance;

X  = the total number of shares of the Corporation’s common stock issuable pursuant to such rights or warrants; and

Y  = the number of shares of the Corporation’s common stock equal to the aggregate price payable to exercise such rights or warrants divided by the Current Market Price determined as of the Ex-Date for such issuance.

To the extent that such rights or warrants are not exercised prior to their expiration or shares of the Corporation’s common stock are otherwise not delivered pursuant to such rights or warrants upon the exercise of such rights or warrants, the Conversion Rate shall be readjusted to such Conversion Rate that would have then been in effect had the adjustment made upon the issuance of such rights or warrants been made on the basis of the delivery of only the number of shares of the Corporation’s common stock actually delivered. If such rights or warrants are only exercisable upon the occurrence of certain triggering events, then the Conversion Rate shall not be adjusted until such triggering events occur. In determining the aggregate offering price payable for such shares of the Corporation’s common stock, the Transfer Agent shall take into account any consideration received for such rights, options or warrants and the value of such consideration (if other than cash, to be determined by the Corporation’s board of directors).

(c) the Corporation subdivides, splits or combines the shares of the Corporation’s common stock into a greater or lesser number of shares of common stock, in which case the Conversion Rate in effect immediately following the effective date of such share subdivision, split or combination shall be multiplied by the following fraction:

    OS₁

OS₀

where

OS₀  = the number of shares of the Corporation’s common stock outstanding immediately prior to the effective date of such share subdivision, split or combination; and

OS₁  = the number of shares of the Corporation’s common stock outstanding immediately after the opening of business on the effective date of such share subdivision, split or combination.

(d) the Corporation distributes to all holders of the Corporation’s common stock evidences of the Corporation’s indebtedness, shares of capital stock, securities, cash or other assets (excluding any dividend or distribution covered by paragraphs G.4(a) or G.4(e), any rights or warrants referred to in paragraph G.4(b), any dividend or distribution paid exclusively in cash, any consideration

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payable in connection with a tender or exchange offer made by the Corporation or any of its subsidiaries, and any dividend of shares of capital stock of any class or series, or similar equity interests, of or relating to a subsidiary or other business unit in the case of a Spin-Off), in which case the Conversion Rate in effect immediately prior to the close of business on the date fixed for the determination of shareholders entitled to receive such distribution shall be multiplied by the following fraction:

        SP₀

SP₀ – FMV

where

SP₀  = the Current Market Price per share of the Corporation’s common stock on the date fixed for determination; and

FMV = the fair market value, as determined by the Corporation’s board of directors, of the portion of the evidences of indebtedness, shares, securities, cash and other assets so distributed applicable to one share of the Corporation’s common stock.

In the event that the Corporation makes a distribution to all holders of the Corporation’s common stock consisting of capital stock of, or similar equity interests in, or relating to a subsidiary or other business unit of the Corporation (herein referred to as a “Spin-Off”), the Conversion Rate shall be adjusted by multiplying the Conversion Rate in effect immediately prior to the close of business on the date fixed for the determination of shareholders entitled to receive such distribution by a fraction:

    MP₀ + MP_S

MP₀

where

MP₀  = the Current Market Price per share of the Corporation’s common stock as of the fifteenth Trading Day after the Ex-Date for such distribution; and

MP_S  = the fair market value of the portion of those shares of capital stock or similar equity interests so distributed applicable to one share of the Corporation’s common stock as of the fifteenth Trading Day after the Ex-Date for such distribution (or, if such shares of capital stock or equity interests are listed on a national or regional securities exchange, the average of the daily closing price of such securities on each of the five consecutive Trading Days ending on such fifteenth Trading Day).

(e) the Corporation makes a distribution consisting exclusively of cash to all holders of the Corporation’s common stock, excluding (a) any cash that is distributed in a Reorganization Event or as part of a distribution referred to in paragraph G.4(d), (b) any dividend or distribution in connection with the Corporation’s liquidation, dissolution or winding up, and (c) any consideration payable in connection with a tender or exchange offer made by the Corporation or any of the Corporation’s subsidiaries, in such event, the Conversion Rate in effect immediately prior to the close of business on the date fixed for determination of the holders of the Corporation’s common stock entitled to receive such distribution shall be multiplied by the following fraction:

        SP₀

SP₀ – C

where

SP₀  = the Current Market Price per share of the Corporation’s common stock on the date fixed for such determination; and

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C  = the amount per share of the Corporation’s common stock of the dividend or distribution.

In the event that a dividend or distribution described in this paragraph G.4(e) is not so made, the Conversion Rate shall be readjusted, effective as of the date the Corporation’s board of directors publicly announces its decision not to pay such dividend or distribution, to the Conversion Rate that would then be in effect if such dividend or distribution had not been declared.

(f) the Corporation or any of the Corporation’s subsidiaries successfully completes a tender or exchange offer for the Corporation’s common stock that involves the payment of consideration with a value per share of the Corporation’s common stock exceeding the Current Market Price per share of the Corporation’s common stock on the last Trading Day immediately succeeding the last day on which tenders or exchanges may be made pursuant to such tender or exchange offer, in which case the Conversion Rate in effect immediately prior to the close of business on the eighth Trading Day after the date of expiration of the tender or exchange offer shall be divided by the following fraction:

    (SP₀ × OS₁) + AC    

OS₀ × SP₀

where

SP₀  = the Current Market Price per share of the Corporation’s common stock on the seventh Trading Day after the date of expiration of the tender or exchange offer;

OS₀  = the number of shares of the Corporation’s common stock outstanding prior to giving effect to such tender or exchange offer (including any shares validly tendered and not withdrawn);

OS₁  = the number of shares of the Corporation’s common stock outstanding (including any shares validly tendered and not withdrawn) on the seventh day after the date of expiration of the tender or exchange offer; and

AC  = the amount of cash plus the fair market value of the aggregate consideration payable for all the shares of the Corporation’s common stock purchased in the tender or exchange offer, as determined by the Corporation’s board of directors.

In the event that the Corporation, or one of its subsidiaries, is obligated to purchase shares of the Corporation’s common stock pursuant to any such tender offer or exchange offer, but the Corporation, or such subsidiary, is permanently prevented by applicable law from effecting any such purchases, or all such purchases are rescinded, then the Conversion Rate shall be readjusted to be such Conversion Rate that would then be in effect if such tender offer or exchange offer had not been made.

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Except as set forth in the preceding paragraph, if the application of this paragraph G.4(f) to any tender offer or exchange offer would result in a decrease in the Conversion Rate, no adjustment shall be made for such tender offer or exchange offer under this paragraph G.4(f).

(g) To the extent that the Corporation has a rights plan in effect with respect to the Corporation’s common stock on any Conversion Date, upon conversion of any shares of the Convertible Preferred Stock, each holder thereof shall receive, in addition to shares of the Corporation’s common stock, the rights under the rights plan, unless, prior to such Conversion Date, the rights have separated from the Corporation’s common stock, in which case the Conversion Rate shall be adjusted at the time of separation as if the Corporation made a distribution to all holders of the Corporation’s common stock as described in paragraph G.4(d), subject to readjustment in the event of the expiration, termination or redemption of such rights.

(h) Notwithstanding anything herein to the contrary, no adjustment under this paragraph G.4 need be made to the Conversion Rate unless such adjustment would require an increase or decrease of at least 1% of the Conversion Rate then in effect. Any lesser adjustment shall be carried forward and shall be made at the time of and together with the next subsequent adjustment, if any, which, together with any adjustment or adjustments so carried forward, shall amount to an increase or decrease of at least 1% of such Conversion Rate; provided that (i) on the conversion date for any Convertible Preferred Stock and (ii) prior to determining the amount of any dividend payable by the Corporation, adjustments to the Conversion Rate shall be made with respect to any such adjustment carried forward that has not been taken into account before such date. Adjustments to the Conversion Rate shall be calculated to the nearest 1/10,000th of a share.

(i) The Conversion Rate shall not be adjusted:

(i) upon the issuance of any the Corporation’s common stock pursuant to any present or future plan providing for the reinvestment of dividends or interest payable on the Corporation’s securities and the investment of additional optional amounts in common stock under any plan;

(ii) upon the issuance of any of the Corporation’s common stock or rights or warrants to purchase those shares pursuant to any present or future employee, director or consultant benefit plan or program of or assumed by the Corporation or any of its subsidiaries;

(iii) upon the issuance of any of the Corporation’s common stock pursuant to any option, warrant, right or exercisable, exchangeable or convertible security outstanding as of the Issue Date;

(iv) for a change in the par value or no par value of the Corporation’s common stock; or

(v) for accrued, cumulated and unpaid dividends.

5. No adjustment to the Conversion Rate need be made if holders of the Convertible Preferred Stock may participate in the transaction that would otherwise give rise to such adjustment, so long as the distributed assets or securities the holders of the Convertible Preferred Stock would receive upon conversion of the Convertible Preferred Stock (if such assets or securities are convertible, exchangeable, or exercisable) are convertible, exchangeable or exercisable, as applicable, without any loss of rights or privileges for a period of at least 45 days following conversion of the Convertible Preferred Stock.

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6. If the Corporation shall take a record of the holders of the Corporation’s common stock for the purpose of entitling them to receive a dividend or other distribution, and shall thereafter (and before the dividend or distribution has been paid or delivered to stockholders) legally abandon its plan to pay or deliver such dividend or distribution, then thereafter no adjustment in the Conversion Rate then in effect shall be required by reason of the taking of such record.

7. Upon any increase or decrease in the Conversion Rate, then, and in each such case, the Corporation promptly shall deliver, or cause to be delivered, to each holder of Convertible Preferred Stock a certificate signed by an authorized officer of the Corporation, setting forth in reasonable detail the event requiring the adjustment and the method by which such adjustment was calculated and specifying the increased or decreased Conversion Rate then in effect following such adjustment.

8. In the event of (a) any consolidation or merger of the Corporation with or into another person (other than a merger or consolidation in which the Corporation is the continuing corporation and in which the shares of the Corporation’s common stock outstanding immediately prior to the merger or consolidation are not exchanged for cash, securities or other property of the Corporation or another person), (b) any sale, transfer, lease or conveyance to another person of all or substantially all of the Corporation’s property and assets, (c) any reclassification of the Corporation’s common stock into securities including securities other than the Corporation’s common stock, or (d) any statutory exchange of the Corporation’s securities with another person (other than in connection with a merger or acquisition) (each herein referred to as a “Reorganization Event”), each share of Convertible Preferred Stock outstanding immediately prior to such Reorganization Event shall, without the consent of the holders of the Convertible Preferred Stock, become convertible into the kind of securities, cash and other property that such holder would have been entitled to receive if such holder had converted its Convertible Preferred Stock into shares of the Corporation’s common stock immediately prior to such Reorganization Event. For purposes of the foregoing, the type and amount of consideration that a holder of Convertible Preferred Stock would have been entitled to receive as a holder of the Corporation’s common stock in the case of any Reorganization Event or other transaction that causes the Corporation’s common stock to be converted into the right to receive more than a single type of consideration (determined based in part upon any form of stockholder election) shall be deemed to be the weighted average of the types and amounts of consideration received by the holders of the Corporation’s common stock that affirmatively make such an election.

The Corporation may make such increases in the Conversion Rate as it deems advisable in order to avoid or diminish any income tax to holders of the Corporation’s common stock resulting from any dividend or distribution of its shares (or issuance of rights or warrants to acquire its shares) or from any event treated as such for income tax purposes or for any other reason.

9. The Corporation shall at all times reserve and keep available for issuance upon the conversion of the Convertible Preferred Stock such number of authorized but unissued shares of the Corporation’s common stock as shall from time to time be sufficient to permit the conversion of all outstanding shares of Convertible Preferred Stock, and shall take all action required to increase the authorized number of shares of the Corporation’s common stock if at any time there shall be insufficient unissued shares of the Corporation’s common stock to permit such reservation or to permit the conversion of all outstanding shares of Convertible Preferred Stock or the payment or partial payment of dividends declared on Convertible Preferred Stock that are payable in shares of the Corporation’s common stock.

10. The issuance or delivery of certificates for shares of the Corporation’s common stock upon the conversion of shares of Convertible Preferred Stock or the payment or partial payment of a dividend on Convertible Preferred Stock in shares of the Corporation’s common stock, shall be made without charge to the converting holder or recipient of shares of Convertible Preferred Stock for such

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certificates or for any tax in respect of the issuance or delivery of such certificates or the securities represented thereby, and such certificates shall be issued or delivered in the respective names of, or in such names as may be directed by, the holders of the shares of Convertible Preferred Stock converted; provided, however, that the Corporation shall not be required to pay any tax which may be payable in respect of any transfer involved in the issuance and delivery of any such certificate in a name other than that of the holder of the shares of the relevant Convertible Preferred Stock and the Corporation shall not be required to issue or deliver such certificate unless or until the person(s) requesting the issuance or delivery thereof shall have paid to the Corporation the amount of such tax or shall have established to the reasonable satisfaction of the Corporation that such tax has been paid.

H. CONVERSION UPON FUNDAMENTAL CHANGE.

1. If a Fundamental Change occurs, each holder of Convertible Preferred Stock that converts its shares of Convertible Preferred Stock at any time during the period (the “Fundamental Change Conversion Period”) beginning on the Fundamental Change Effective Date and ending on the date that is 15 days after the Fundamental Change Effective Date (the “Expiration Date”) shall receive, for each share of Convertible Preferred Stock, the greater of:

(a) (1) a number of shares of the Corporation’s common stock equal to the then-applicable Conversion Rate, plus (2) the Make-Whole Premium, if any, described in paragraph I; and

(b) a number of shares of the Corporation’s common stock calculated by dividing the Liquidation Preference by the greater of (i) the average of the Daily VWAP of the Corporation’s common stock on each of the 10 consecutive Trading Days ending on the Trading Day immediately preceding the Fundamental Change Effective Date and (ii) $5.00.

2. In addition to the number of shares of the Corporation’s common stock issuable upon conversion of each share of Convertible Preferred Stock at the option of the holder on any Conversion Date during the Fundamental Change Conversion Period, each converting holder shall have the right to receive an amount equal to all accrued, cumulated and unpaid dividends on such converted shares of Convertible Preferred Stock, whether or not declared prior to that date, for all prior Dividend Periods ending on or prior to the Dividend Payment Date immediately preceding the Conversion Date (other than previously declared dividends on the Convertible Preferred Stock payable to holders of record as of a prior date), provided that the Corporation is then legally permitted to pay such dividends. The amount payable in respect of such dividends shall be paid in cash, shares of the Corporation’s common stock (or Publicly Traded Common Stock of the acquiror, if applicable) or a combination thereof in accordance with the provisions set forth in paragraph D, including the provisions setting forth the method for valuing the Corporation’s common stock (which shall also apply to any Publicly Traded Common Stock of the acquiror), set forth in paragraph E.2.

3. The Corporation must give notice (a “Fundamental Change Notice”) of each Fundamental Change to all record holders of the Convertible Preferred Stock at least 20 days prior to the anticipated Fundamental Change Effective Date (determined in good faith by the Corporation’s board of directors) of such Fundamental Change. The Fundamental Change Notice shall be given by first-class mail to each record holder of shares of Convertible Preferred Stock, at such holder’s address as the same appears on the books of the Corporation. Each such Fundamental Change Notice shall state (i) the anticipated Fundamental Change Effective Date; (ii) the Expiration Date; (iii) the name and address of the Transfer Agent; and (iv) the procedures that holders must follow to convert their shares of Convertible Preferred Stock pursuant to this paragraph H.

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4. On or before the Expiration Date, each holder of shares of Convertible Preferred Stock wishing to exercise its conversion right pursuant to this paragraph H shall surrender the certificate or certificates representing the shares of Convertible Preferred Stock to be converted in the manner and at the place designated in the Fundamental Change Notice, and on such date the shares of Common Stock (or Publicly Traded Common Stock of the acquiror, if applicable) and the payment for unpaid dividends due to such holder shall be delivered to the person whose name appears on such certificate or certificates as the owner thereof and the shares of Convertible Preferred Stock represented by each surrendered certificate shall be returned to authorized but unissued shares of Convertible Preferred Stock.

I. MAKE-WHOLE PREMIUM FOR CONVERSION UPON A FUNDAMENTAL CHANGE.

1. Holders who elect to convert shares of Convertible Preferred Stock during the Fundamental Change Conversion Period shall receive, in addition to the number of shares of the Corporation’s common stock issuable upon conversion calculated pursuant to paragraph H, an additional number of shares of the Corporation’s common stock for each share of Convertible Preferred Stock so converted (the “Additional Shares” or the “Make-Whole Premium”), if any, as set forth below in this paragraph I.

2. The number of Additional Shares shall be determined by reference to the table below, based on the Fundamental Change Effective Date and the Fundamental Change Stock Price:

	Fundamental Change Stock Price
Fundamental Change Effective Date	$	18.50	$	20.00	$	30.00	$	40.00	$	50.00	$	60.00	$	70.00	$	80.00	$	90.00	$	100.00	$	110.00	$	120.00
September 29, 2009		0.9009		0.8699		0.5005		0.3253		0.2247		0.1607		0.1172		0.0864		0.0639		0.0470		0.0344		0.0247
October 1, 2010		0.9009		0.8146		0.4645		0.3020		0.2094		0.1503		0.1100		0.0812		0.0601		0.0443		0.0323		0.0231
October 1, 2011		0.9009		0.7459		0.4115		0.2657		0.1847		0.1333		0.0982		0.0729		0.0542		0.0401		0.0293		0.0209
October 1, 2012		0.9009		0.6756		0.3354		0.2089		0.1444		0.1051		0.0784		0.0590		0.0445		0.0333		0.0246		0.0178
October 1, 2013		0.9009		0.6114		0.2298		0.1188		0.0768		0.0556		0.0421		0.0323		0.0249		0.0189		0.0142		0.0103
October 1, 2014 and thereafter		0.9009		0.5859		0.1310		0.0082		0.0000		0.0000		0.0000		0.0000		0.0000		0.0000		0.0000		0.0000

3. The Fundamental Change Stock Prices set forth in the foregoing table shall be adjusted as of any date on which the Conversion Rate is adjusted. The adjusted Fundamental Change Stock Prices shall equal the Fundamental Change Stock Prices applicable immediately prior to such adjustment multiplied by a fraction, the numerator of which is the Conversion Rate immediately prior to the adjustment giving rise to the Fundamental Change Stock Price adjustment and the denominator of which is the Conversion Rate as so adjusted. Each of the Make-Whole Premiums in the table shall be subject to adjustment in the same manner as the Conversion Rate as set forth in paragraph G.4.

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4. The exact Fundamental Change Stock Price and Fundamental Change Effective Dates may not be set forth on the table, in which case:

(a) if the Fundamental Change Stock Price is between two Fundamental Change Stock Price amounts on the table or the Fundamental Change Effective Date is between two Fundamental Change Effective Dates on the table, the Make-Whole Premium shall be determined by straight-line interpolation between the Make-Whole Premium amounts set forth for the higher and lower Fundamental Change Stock Price amounts and the two dates, as applicable, based on a 365-day year;

(b) if the Fundamental Change Stock Price is in excess of $120.00 per share (subject to adjustment as described above), then no Make-Whole Premium amount shall be paid; and

(c) if the stock price is less than $18.50 per share (subject to adjustment as described above), then no Make-Whole Premium amount shall be paid.

5. The Corporation shall only be required to deliver the Make-Whole Premium with respect to shares of Convertible Preferred Stock surrendered for conversion during any Fundamental Change Conversion Period.

J. MANDATORY CONVERSION.

1. At any time on or after October 1, 2014, if the Daily VWAP of the Corporation’s common stock equals or exceeds 150% of the then-prevailing Conversion Price for at least 20 Trading Days in a period of 30 consecutive Trading Days, including the last Trading Day of such 30-Trading Day period, the Corporation may at its option (by issuing a press release as provided in paragraph J.2), cause the Convertible Preferred Stock to be automatically converted (a “Mandatory Conversion”) into a number of shares of the Corporation’s common stock for each share of the Convertible Preferred Stock equal to the then-applicable Conversion Rate. In connection with any such mandatory conversion, the Corporation shall also pay converting holders any accumulated and unpaid dividends on their shares of the Convertible Preferred Stock. The amount payable in respect of such accumulated and unpaid dividends shall be paid in cash, shares of common stock or a combination thereof in accordance with the provisions set forth in paragraphs D and E, including the provisions setting forth the method for valuing the Corporation’s common stock, set forth in paragraph E.2.

2. To exercise the mandatory conversion right described in paragraph J.1, the Corporation shall issue a press release for publication on the Dow Jones News Service or Bloomberg Business News (or if either such service is not available another broadly disseminated news or press release service selected by the Corporation) prior to the opening of business on the fifth Trading Day following any date on which the conditions described in paragraph J.1 are met, announcing such a mandatory conversion. The Corporation shall also give notice by mail or by publication (with subsequent prompt notice by mail) to the registered holders of the Convertible Preferred Stock (not more than four Business Days after the date of the press release) of the mandatory conversion announcing the Corporation’s intention to convert the Convertible Preferred Stock. The Conversion Date shall be a date selected by the Corporation (the date so selected, the “Mandatory Conversion Date”) and shall be no more than ten Business Days after the date on which the Corporation issues such press release.

3. In addition to any information required by applicable law or regulation, the press release and notice of a mandatory conversion described in Paragraph J.2 shall state, as appropriate: (a) the Mandatory Conversion Date; (b) the number of shares of the Corporation’s common stock to be issued upon conversion of each share of Convertible Preferred Stock; (c) the number of shares of Convertible Preferred Stock to be converted; (d) whether the Corporation shall pay accumulated dividends in cash, shares of the Corporation’s common stock or a combination thereof; and (e) that dividends on the shares of Convertible Preferred Stock to be converted shall cease to accrue on the Mandatory Conversion Date.

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4. On and after the Mandatory Conversion Date, dividends shall cease to accrue on the Convertible Preferred Stock called for a mandatory conversion and all rights of holders of such Convertible Preferred Stock shall terminate, except for the right to receive shares of the Corporation’s common stock issuable upon conversion thereof, any accumulated and unpaid dividends and cash in lieu of fractional shares. The dividend payment with respect to Convertible Preferred Stock called for a mandatory conversion on a date during the period between the close of business on any Record Date for the payment of dividends to the close of business on the corresponding Dividend Payment Date shall be payable on such Dividend Payment Date to the record holder of such share on such Record Date if such Convertible Preferred Stock has been converted after such Record Date and prior to such Dividend Payment Date.

K. REDEMPTION.

1. The Convertible Preferred Stock shall not be redeemable at the Corporation’s option.

2. The Convertible Preferred Stock shall not be redeemable at the option of any holder of Convertible Preferred Stock.

L. FRACTIONAL SHARES. No fractional shares of the Corporation’s common stock shall be issued to holders of the Convertible Preferred Stock upon conversion. In lieu of any fractional shares of the Corporation’s common stock otherwise issuable in respect of the aggregate number of shares of the Convertible Preferred Stock of any holder that are converted, that holder shall be entitled to receive an amount in cash (computed to the nearest cent) equal to the same fraction of:

1. in the case of a conversion of Convertible Preferred Stock as a result of a Fundamental Change or a Mandatory Conversion, the average of the daily closing price per share of common stock on each of the ten consecutive Trading Days preceding the Trading Day immediately preceding the date of conversion; or

2. in the case of each conversion at the option of a holder, the Daily Closing Price per common share determined as of the second Trading Day immediately preceding the Conversion Date.

Notwithstanding the foregoing, the Corporation may elect to round up the number of shares of the Corporation’s common stock to be delivered upon conversion to the next highest whole number of shares in lieu of making such cash payment. If more than one share of Convertible Preferred Stock is surrendered for conversion at one time by or for the same holder, the number of full common shares issuable upon conversion thereof shall be computed on the basis of the aggregate number of shares of Convertible Preferred Stock so surrendered.

M. VOTING RIGHTS.

1. The holders of record on the relevant Record Date of the Convertible Preferred Stock, except as otherwise required under Texas law or as set forth in paragraph M.2, shall not be entitled to vote on any matter required or permitted to be voted upon by the shareholders of the Corporation.

2. If and whenever at any time dividends on the Convertible Preferred Stock are in arrears and unpaid for six or more Dividend Periods (whether or not consecutive), then the holders of shares of Convertible Preferred Stock, voting as a single class with any Parity Stock having similar voting rights that are then exercisable (the “Voting Rights Class”), shall be entitled at the Corporation’s next regular or special meeting of shareholders to elect two additional directors to the Corporation’s board of directors. Upon the election of any such additional directors, the number of directors that comprise the

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Corporation’s board shall be increased by such number of additional directors. Such voting rights and the terms of the directors so elected shall continue until such time as the dividend arrearage on the Convertible Preferred Stock has been paid in full. At any time after voting power to elect directors shall have become vested and be continuing in the holders of the Convertible Preferred Stock, or if a vacancy shall exist in the office of any such additional director, the Corporation’s board of directors may, and upon written request of the holders of record of at least 25% of the outstanding Convertible Preferred Stock addressed to the chairman of the Corporation’s board shall, call a special meeting of the Voting Rights Class for the purpose of electing the directors that such holders are entitled to elect. At any such meeting held for the purpose of electing such a director, the presence in person or by proxy of the holders of at least a majority of the Convertible Preferred Stock shall be required to constitute a quorum of such Convertible Preferred Stock.

3. In addition, for so long any shares of Convertible Preferred Stock remain outstanding, unless a greater percentage shall be required by law, the affirmative vote or consent of the holders of at least 66 ²/3% of the Voting Rights Class, in person or by proxy, at an annual meeting of the Corporation’s stockholders or at a special meeting called for such purpose, or by written consent in lieu of such meeting, shall be required to alter, repeal or amend, whether by merger, consolidation, combination, reclassification or otherwise, any provisions of the Corporation’s articles of incorporation or this Designating Resolution if the amendment would amend, alter or affect the powers, preferences or rights of the Convertible Preferred Stock so as to adversely affect the holders thereof, including, without limitation, the creation of, increase in the authorized number of, or issuance of, shares of any class or series of Senior Stock. Notwithstanding the foregoing, the authorization of, the increase in the authorized amount of, or the issuance of any shares of any class or series of Parity Stock or Junior Stock shall not require the consent of the holders of the Convertible Preferred Stock, and shall not be deemed to adversely affect the powers, preferences or rights of the holders of the Convertible Preferred Stock.

4. The number of votes that each share of Convertible Preferred Stock and any Parity Stock participating in the votes described above shall have shall be in proportion to the liquidation preference of such share.

N. REGISTRATION RIGHTS.

1. Shelf Registration.

(a) So long as any Registrable Security exists:

(i) The Corporation shall, as soon as practicable but in any event no later than the 20th day after the Issue Date, file with the Commission, and thereafter use its commercially reasonable efforts to cause to be declared effective as promptly as practicable but in any event no later than January 1, 2010, a shelf registration statement (the “Shelf Registration Statement”) on an appropriate form under the Securities Act relating to the offer and sale (either directly by holders of the Convertible Preferred Stock or by the Dividend Agent on behalf of such holders) of any share of Registrable Securities from time to time in accordance with the methods of distribution set forth in the Shelf Registration Statement and Rule 415 under the Securities Act (hereinafter, the “Shelf Registration”).

(ii) The Corporation shall, subject to its rights to suspend use of the Shelf Registration Statement pursuant to paragraph N.2(b), use its commercially reasonable efforts to keep the Shelf Registration Statement continuously effective until such time as there are no longer any Registrable Securities.

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(b) Notwithstanding any other provisions of this Designating Resolution to the contrary, the Corporation shall cause the Shelf Registration Statement and the related prospectus and any amendment or supplement thereto, as of the effective date of the Shelf Registration Statement, amendment or supplement, (i) to comply in all material respects with the applicable requirements of the Securities Act and the rules and regulations of the Commission and (ii) not to contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

2. Registration Procedures. In connection with the Shelf Registration contemplated by paragraph N.1:

(a) The Corporation shall include in the prospectus included in the Shelf Registration Statement (or, if permitted by Commission Rule 430B(b), in a prospectus supplement that becomes a part thereof pursuant to Commission Rule 430B(f)) that is delivered to any holder of Registrable Securities pursuant to paragraphs N.2(d) and N.2(h), the names of the holders of Registrable Securities who propose to sell Registrable Securities pursuant to the Shelf Registration Statement, as selling securityholders.

(b) The Corporation shall give written notice to the holders of the Registrable Securities included within the coverage of the Shelf Registration Statement (which notice pursuant to paragraphs N.2(b)(ii)-N.2(b)(v) shall be accompanied by an instruction to suspend the use of the prospectus until the requisite changes have been made):

(i) when the Shelf Registration Statement or any amendment thereto has been filed with the Commission and when the Shelf Registration Statement or any post-effective amendment thereto has become effective;

(ii) of any request by the Commission for amendments or supplements to the Shelf Registration Statement or the prospectus included therein or for additional information;

(iii) of the issuance by the Commission of any stop order suspending the effectiveness of the Shelf Registration Statement or the initiation of any proceedings for that purpose, of the issuance by the Commission of a notification of objection to the use of the form on which the Shelf Registration Statement has been filed, and of the happening of any event that causes the Corporation to become an “ineligible issuer,” as defined in Commission Rule 405;

(iv) of the receipt by the Corporation or its legal counsel of any notification with respect to the suspension of the qualification of the Registrable Securities for sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and

(v) of the happening of any event that requires the Corporation to make changes in the Shelf Registration Statement or the prospectus in order that the Shelf Registration Statement or the prospectus do not contain an untrue statement of a material fact nor omit to state a material fact required to be stated therein or necessary to make the statements therein (in the case of the prospectus, in light of the circumstances under which they were made) not misleading; provided that the Corporation may suspend the use of the prospectus pursuant to this paragraph N.2(b)(v) for no more than 15 consecutive days in any fiscal quarter or 30 days in the aggregate in any twelve-month period.

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(c) The Corporation shall use commercially reasonable efforts to obtain the withdrawal, at the earliest possible time, of any order suspending the effectiveness of the Shelf Registration Statement.

(d) The Corporation shall furnish to each holder of Registrable Securities included within the coverage of the Shelf Registration Statement, without charge, if such holder so requests in writing, at least one copy of the Shelf Registration Statement and any post-effective amendment thereto, including financial statements and schedules and all exhibits thereto (including those, if any, incorporated by reference).

(e) The Corporation shall deliver to each holder of Registrable Securities included within the coverage of the Shelf Registration Statement, without charge, as many copies of the prospectus (including each preliminary prospectus) included in the Shelf Registration Statement and any amendment or supplement thereto as such person may reasonably request, and consent to the use of the prospectus or any amendment or supplement thereto by each of the selling holders in connection with the offering and sale of the Registrable Securities covered by the prospectus, or any amendment or supplement thereto, included in the Shelf Registration Statement.

(f) Prior to any public offering of the Registrable Securities pursuant to the Shelf Registration Statement, the Corporation shall register or qualify or cooperate with the holders of the Registrable Securities included therein and their counsel in connection with the registration or qualification of the Registrable Securities for offer and sale under the securities or “blue sky” laws of such states of the United States as any holder thereof reasonably requests in writing and do any and all other acts or things necessary or advisable to enable the offer and sale in such jurisdictions of the Registrable Securities covered by the Shelf Registration Statement; provided, however, that the Corporation shall not be required to (i) qualify generally to do business in any jurisdiction where it is not then so qualified or (ii) take any action which would subject it to general service of process or to taxation in any jurisdiction where it is not then so subject.

(g) Upon the occurrence of any event contemplated by paragraphs N.2(b)(ii) through N.2(b)(v), the Corporation shall promptly prepare and file a post-effective amendment to the Shelf Registration Statement or a supplement to the related prospectus and any other required document so that, as thereafter delivered to holders of the Registrable Securities or purchasers of Registrable Securities, the prospectus shall not contain an untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading.

(h) Not later than the effective date of the Shelf Registration Statement, the Corporation shall provide CUSIP numbers for the Registrable Securities registered for resale under the Shelf Registration Statement on such date. Not later than the applicable Dividend Payment Date, the Corporation shall provide to The Depository Trust Company one or more global certificates for such Registrable Securities, in a form eligible for deposit with The Depository Trust Company.

(i) The Corporation shall comply with all rules and regulations of the Commission to the extent and so long as they are applicable to the Shelf Registration and shall make generally available to its security holders (or otherwise provide in accordance with Section 11(a) of the Securities Act) an earnings statement satisfying the provisions of Section 11(a) of the Securities Act, no later than 45 days after the end of a 12-month period (or 90 days, if such period is a fiscal year) beginning with the first month of the Corporation’s first fiscal quarter commencing after the effective date of the Shelf Registration Statement, which statement shall cover such 12-month period.

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(j) If a holder of Registrable Securities wishes to sell its Registrable Securities pursuant to the Shelf Registration Statement and related prospectus, it shall do so only in accordance with this paragraph N.2(j). Following the date that the Shelf Registration Statement is declared effective (or becomes effective automatically upon filing), each holder wishing to sell Registrable Securities pursuant to the Shelf Registration Statement and related prospectus agrees to complete and deliver a Notice and Questionnaire, in substantially the form set forth as Annex A to the Offering Circular for the Convertible Preferred Stock, to the Corporation at least 10 days prior to any intended distribution of Registrable Securities under the Shelf Registration Statement. Within the later of (1) 10 days after receipt of the completed Notice and Questionnaire and (2) five days after the expiration of any Suspension Period in effect when such Notice and Questionnaire is received, the Corporation shall file, if required by applicable law, a post-effective amendment to the Shelf Registration Statement or a supplement to the prospectus contained in the Shelf Registration Statement.

(k) No holder shall be entitled to sell any of its Registrable Securities pursuant to the Shelf Registration Statement or to receive a prospectus relating thereto, unless such holder has furnished the Corporation a completed Notice and Questionnaire as required pursuant to paragraph N.2(j) (including the information required to be included in such Notice and Questionnaire) and the information set forth in the next sentence. Each holder of Registrable Securities who has delivered such Notice and Questionnaire shall promptly furnish to the Corporation (1) all further information required to be disclosed in order to make the information previously furnished to the Corporation in such Notice and Questionnaire not misleading and (2) any other information regarding such holder and the distribution of such Registrable Securities as the Corporation may from time to time reasonably request. Any sale of any Registrable Securities by a holder shall constitute a representation and warranty by such holder that the information relating to such holder and its plan of distribution is as set forth in the prospectus delivered to such holder in connection with such disposition, that such prospectus does not as of the time of such sale contain any untrue statement of a material fact relating to or provided by such holder or its plan of distribution and that such prospectus does not as of the time of such sale omit to state any material fact relating to or provided by such holder or its plan of distribution necessary to make the statements in such prospectus, in light of the circumstances under which they were made, not misleading.

(l) Upon actual receipt of any notice from the Corporation of the happening of any event of the kind described in paragraphs N.2(b)(ii) through N.2(b)(v), holders of Registrable Securities covered by the Shelf Registration Statement shall forthwith discontinue disposition of such Registrable Securities and suspend use of such prospectus until such holder’s receipt of the copies of the supplemented or amended prospectus contemplated by paragraph N.2(g) (such period, the “Suspension Period”), or until it is advised in writing by the Corporation that the use of the applicable prospectus may be resumed, and has received copies of any amendments or supplements thereto.

(m) The Corporation shall enter into such customary agreements (including, if requested, an underwriting agreement in customary form) in order to facilitate the disposition of the Registrable Securities pursuant to the Shelf Registration.

(n) The Corporation shall (i) make reasonably available for inspection by the holders of Registrable Securities, any underwriter participating in any disposition pursuant to the Shelf Registration Statement and any attorney, accountant or other agent retained by the holders of Registrable Securities or any such underwriter all relevant financial and other records, pertinent corporate documents and properties of the Corporation and (ii) cause the Corporation’s officers, directors, employees, accountants and auditors to supply all relevant information reasonably requested by the holders of Registrable Securities or any such underwriter, attorney, accountant or agent in connection with the Shelf Registration Statement, in each case, as shall be reasonably necessary to enable such persons, to conduct a reasonable investigation within the meaning of Section 11 of the Securities Act; provided, however, that with respect to holders of Registrable Securities the foregoing inspection and information gathering shall be coordinated by one counsel designated by the Corporation and acting on behalf of such other parties.

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(o) In connection with the Shelf Registration, the Corporation, if requested by the Managing Underwriters, if any, shall cause (i) its counsel to deliver an opinion relating to the Registrable Securities in customary form addressed to such managing underwriters, if any, thereof; (ii) its officers to execute and deliver all customary documents and certificates and updates thereof requested by any underwriters of the applicable Registrable Securities and (iii) its independent public accountants to provide to any underwriter therefor a comfort letter in customary form and covering matters of the type customarily covered in comfort letters in connection with primary underwritten offerings, subject to receipt of appropriate documentation as contemplated, and only if permitted, by the American Institute of Certified Public Accountants’ Professional Standard AU Section 634 “Letters for Underwriters and Certain Other Requesting Parties.”

(p) The Corporation shall use its commercially reasonable efforts to cause the Registrable Securities included in such Shelf Registration Statement to be, upon resale thereunder, listed on each securities exchange, if any, on which any shares of common stock are then listed.

(q) The Corporation shall use its commercially reasonable efforts to take all other steps necessary to effect the registration of the Registrable Securities covered by the Shelf Registration Statement contemplated hereby.

3. Registration Expenses. All expenses incident to the Corporation’s performance of and compliance with the provisions relating to the Shelf Registration shall be borne by the Corporation, regardless of whether the Shelf Registration Statement is ever filed or becomes effective, including without limitation:

(a) all registration and filing fees and expenses;

(b) all fees and expenses of compliance with federal securities and state “blue sky” or securities laws;

(c) all expenses of printing (including printing certificates and printing of prospectuses), messenger and delivery services and telephone;

(d) all fees and disbursements of counsel for the Corporation;

(e) all application and filing fees in connection with listing on a national securities exchange or automated quotation system pursuant to the requirements hereof; and

(f) all fees and disbursements of independent certified public accountants of the Corporation (including the expenses of any special audit and comfort letters required by or incident to such performance).

The Corporation shall bear its internal expenses (including, without limitation, all salaries and expenses of its officers and employees performing legal or accounting duties), the expenses of any annual audit and the fees and expenses of any person, including special experts, retained by the Corporation. In connection with the Shelf Registration Statement, the Company shall reimburse the holders of Registrable Securities who are selling or reselling Registrable Securities pursuant to the “Plan of Distribution” contained in the Shelf Registration Statement for the reasonable fees and disbursements of not more than one counsel, who shall be reasonably satisfactory to the Corporation.

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4. Indemnification.

(a) The Corporation agrees to indemnify and hold harmless each holder of Registrable Securities included within the coverage of the Shelf Registration Statement and each person, if any, who controls such holder within the meaning of the Securities Act or the Exchange Act (each holder and such controlling persons are referred to collectively as the “Indemnified Parties”) from and against any losses, claims, damages or liabilities, joint or several, or any actions in respect thereof (including, but not limited to, any losses, claims, damages, liabilities or actions relating to purchases and sales of the Registrable Securities) to which each Indemnified Party may become subject under the Securities Act, the Exchange Act or otherwise, insofar as such losses, claims, damages, liabilities or actions arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in the Shelf Registration Statement or prospectus or in any amendment or supplement thereto or in any preliminary prospectus relating to the Shelf Registration, or arise out of, or are based upon, the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and shall reimburse, as incurred, the Indemnified Parties for any legal or other expenses reasonably incurred by them in connection with investigating or defending any such loss, claim, damage, liability or action in respect thereof; provided, however, that (i) the Corporation shall not be liable in any such case to the extent that such loss, claim, damage or liability arises out of or is based upon any untrue statement or alleged untrue statement or omission or alleged omission made in the Shelf Registration Statement or prospectus or in any amendment or supplement thereto or in any preliminary prospectus relating to a Shelf Registration in reliance upon and in conformity with written information pertaining to such holder and furnished to the Corporation by or on behalf of such holder specifically for inclusion therein and (ii) with respect to any untrue statement or omission or alleged untrue statement or omission made in any prospectus relating to a Shelf Registration Statement, the indemnity provisions contained in this paragraph N.4(a) shall not inure to the benefit of any holder from whom the person asserting any such losses, claims, damages or liabilities purchased the Registrable Securities concerned, to the extent that a prospectus relating to such Registrable Securities was required to be delivered by such holder under the Securities Act in connection with such purchase and any such loss, claim, damage or liability of such holder results from the fact that there was not sent or given to such person, at or prior to the written confirmation of the sale of such Registrable Securities to such person, a copy of the final prospectus if the Corporation had previously furnished copies thereof to such holder.

(b) Each holder of the Registrable Securities, severally and not jointly, by electing to sell its Registrable Securities under the Shelf Registration shall indemnify and hold harmless the Corporation and each person, if any, who controls the Corporation within the meaning of the Securities Act or the Exchange Act from and against any losses, claims, damages or liabilities or any actions in respect thereof, to which the Corporation or any such controlling person may become subject under the Securities Act, the Exchange Act or otherwise, insofar as such losses, claims, damages, liabilities or actions arise out of or are based upon any untrue statement or alleged untrue statement of a material fact contained in a Shelf Registration Statement or prospectus or in any amendment or supplement thereto or in any preliminary prospectus relating to a Shelf Registration, or arise out of or are based upon the omission or alleged omission to state therein a material fact necessary to make the statements therein not misleading, but in each case only to the extent that the untrue statement or omission or alleged untrue statement or omission was made in reliance upon and in conformity with written information pertaining to such holder and furnished to the Corporation by or on behalf of such holder specifically for inclusion therein; and, subject to the limitation set forth immediately preceding this clause, shall reimburse, as incurred, the Corporation for any legal or other expenses reasonably incurred by the Corporation or any such controlling person in connection with investigating or defending any loss, claim, damage, liability or action in respect thereof.

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5. Underwritten Registrations. If any of the Registrable Securities covered by any Shelf Registration are to be sold in an underwritten offering, the investment banker or investment bankers and manager or managers that will administer the offering (the “Managing Underwriters”) shall be selected by the Corporation. No person may participate in any underwritten registration hereunder unless such person (a) agrees to sell such person’s Registrable Securities on the basis reasonably provided in any underwriting arrangements approved by the persons entitled hereunder to approve such arrangements and (b) completes and executes all questionnaires, powers of attorney, indemnities, underwriting agreements and other documents reasonably required under the terms of such underwriting arrangements.

6. Other Registration Rights.

(a) If, following the first five dividend payments on the Convertible Preferred Stock, the Corporation elects to deliver shares of the Corporation’s common stock payable in respect of a dividend on the Convertible Preferred Stock to the Dividend Agent on behalf of the holders of the Convertible Preferred Stock for sale for cash on behalf of such holders, as a condition to such election, (i) the Corporation must either file and have declared effective a new shelf registration statement or amend an existing effective shelf registration statement covering resales of such shares pursuant to Rule 415 under the Securities Act and (ii) such shelf registration statement must be effective at the time of the delivery of such shares in respect of the applicable dividend.

(b) To the extent shares of the Corporation’s common stock issued as payments of dividends on the Convertible Preferred Stock, including dividends paid in connection with a conversion of Convertible Preferred Stock, would not be freely transferable under the Securities Act by a holder of Convertible Preferred Stock who is not an affiliate of the Corporation, the Corporation shall, to the extent such a registration statement is not then filed and effective, use its best efforts to file and maintain the effectiveness of a shelf registration statement covering such shares of the Corporation’s common stock until the earlier of such time as all such shares of the Corporation’s common stock have been resold thereunder and such time as all such shares of the Corporation’s common stock are freely tradable without registration under the Securities Act.

(c) In connection with any shelf registration statement described under paragraph N.6(a) or N.6(b), the provisions set forth in this paragraph N with respect to the Shelf Registration Statement, including the Corporation’s right to suspend use of the Shelf Registration Statement, shall apply.

(d) The Corporation has no obligation to effect any registration for the resale of any Convertible Preferred Stock or any common stock issuable upon conversion of any Convertible Preferred Stock.

O. CERTIFICATES AND TRANSFER RESTRICTIONS.

1. Transfer Restrictions.

(a) The Convertible Preferred Stock shall be substantially in the form of Attachment 1, which is hereby incorporated in and expressly made a part of this Designating Resolution. The Convertible Preferred Stock may have notations, legends, or endorsements required by law, stock exchange rule, agreements to which the Corporation is subject, if any, or usage (provided such notation, legend or endorsement is in a form acceptable to the Corporation).

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(b) Each Convertible Preferred Stock certificate shall bear legends in the following form:

A full statement of the designations, preferences, limitations and relative rights of the shares of each class of stock of the Corporation authorized to be issued is set forth in the Restated Articles of Incorporation of the Corporation, as amended, on file in the Office of the Secretary of State of the State of Texas. The Restated Articles of Incorporation of the Corporation, as amended, on file in the Office of the Secretary of State of the State of Texas, deny the preemptive right of shareholders to acquire unissued or treasury shares of the Corporation. The Corporation shall furnish a copy of its Restated Articles of Incorporation, as amended, to the record holder of this Certificate without charge upon written request to the Secretary of the Corporation at its principal place of business in Houston, Texas.

THIS SECURITY (OR ITS PREDECESSOR) WAS ORIGINALLY ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND THIS SECURITY AND ANY COMMON STOCK ISSUABLE UPON CONVERSION THEREOF MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH PURCHASER OF THIS SECURITY IS HEREBY NOTIFIED THAT THE SELLER OF THIS SECURITY MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER.

THE HOLDER OF THIS SECURITY AGREES FOR THE BENEFIT OF THE CORPORATION THAT (A) THIS SECURITY AND THE COMMON STOCK ISSUABLE UPON CONVERSION HEREOF MAY BE OFFERED, RESOLD, PLEDGED OR OTHERWISE TRANSFERRED, ONLY (I) IN THE UNITED STATES TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144A, (II) PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY RULE 144 THEREUNDER (IF AVAILABLE) OR (III) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT, IN EACH OF CASES (I) THROUGH (III) IN ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES, AND (B) THE HOLDER WILL, AND EACH SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER OF THIS SECURITY OR ANY COMMON STOCK ISSUABLE UPON CONVERSION THEREOF FROM IT OF THE RESALE RESTRICTIONS REFERRED TO IN (A) ABOVE. IN ANY CASE, THE HOLDER HEREOF WILL NOT, DIRECTLY OR INDIRECTLY, ENGAGE IN ANY HEDGING TRANSACTIONS WITH REGARD TO THIS SECURITY EXCEPT AS PERMITTED UNDER THE SECURITIES ACT.

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE PROVISIONS OF A STATEMENT OF RESOLUTIONS ESTABLISHING AND DESIGNATING THE CONVERTIBLE PREFERRED STOCK OF THE CORPORATION. THESE SECURITIES MAY NOT BE TRANSFERRED EXCEPT IN ACCORDANCE WITH SUCH STATEMENT OF RESOLUTIONS.

(c) In addition, each Global Convertible Preferred Stock certificate shall bear legends in the following form:

THIS CERTIFICATE IS IN GLOBAL FORM AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY (“DTC”) OR A NOMINEE THEREOF. THIS CERTIFICATE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY DTC TO A NOMINEE OF DTC OR BY A NOMINEE OF DTC TO DTC OR ANOTHER NOMINEE OF DTC OR BY ANY SUCH NOMINEE TO A SUCCESSOR OF DTC OR A NOMINEE OF SUCH SUCCESSOR DEPOSITORY.

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UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF DTC TO THE CORPORATION OR THE TRANSFER AGENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

(d) Any shares of the Corporation’s common stock issued upon conversion of the Convertible Preferred Stock or payment of dividends prior to September 29, 2010, and any such common stock, as the case may be, held at any time by the Corporation’s affiliates, shall bear legends comparable to those set forth in paragraph O.1(b) unless the Corporation determines in accordance with the Securities Act that such shares of the Corporation’s common stock are no longer restricted or such legends are otherwise not required.

(e) Any purported transfer of shares of Convertible Preferred Stock not permitted hereunder shall be void and of no effect and the purported transferee shall have no rights as a stockholder of the Corporation and no other rights against or with respect to the Corporation.

2. Certificates.

(a) Global Convertible Preferred Stock. The Convertible Preferred Stock shall be issued initially in the form of one or more fully registered global certificates with the global securities legend set forth in paragraphs O.1(b) and O.1(c) (the “Global Convertible Preferred Stock”), which shall be deposited on behalf of the purchasers represented thereby with the Transfer Agent, as custodian for DTC (or with such other custodian as DTC may direct), and registered in the name of DTC or a nominee of DTC, duly executed by the Corporation and countersigned and registered by the Transfer Agent as hereinafter provided. The number of shares of Convertible Preferred Stock represented by Global Convertible Preferred Stock may from time to time be increased or decreased by adjustments made on the records of the Transfer Agent and DTC or its nominee as hereinafter provided.

(b) Book-Entry Provisions. In the event Global Convertible Preferred Stock is deposited with or on behalf of DTC, the Corporation shall execute and the Transfer Agent shall countersign, register and deliver initially one or more Global Convertible Preferred Stock certificates that (a) shall be registered in the name of DTC as depository for such Global Convertible Preferred Stock or the nominee of DTC and (b) shall be delivered by the Transfer Agent to DTC or pursuant to DTC’s instructions or held by the Transfer Agent as custodian for DTC.

Members of, or participants in, DTC (“Agent Members”) shall have no rights under this Designating Resolution with respect to any Global Convertible Preferred Stock held on their behalf by DTC or by the Transfer Agent as the custodian of DTC or under such Global Convertible Preferred Stock, and DTC may be treated by the Corporation, the Transfer Agent and any agent of the Corporation or the Transfer Agent as the absolute owner of such Global Convertible Preferred Stock for all purposes whatsoever. Notwithstanding the foregoing, nothing herein shall prevent the Corporation, the Transfer Agent or any agent of the Corporation or the Transfer Agent from giving effect to any written certification, proxy or other authorization furnished by DTC or impair, as between DTC and its Agent Members, the operation of customary practices of DTC governing the exercise of the rights of a holder of a beneficial interest in any Global Convertible Preferred Stock.

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(c) Certificated Convertible Preferred Stock. Except as provided in paragraph O.3, owners of beneficial interests in Global Convertible Preferred Stock will not be entitled to receive physical delivery of Convertible Preferred Stock in fully registered certificated form (“Certificated Convertible Preferred Stock”).

3. Execution, Countersignature and Registration. Two Officers shall sign the Convertible Preferred Stock certificate for the Corporation by manual or facsimile signature.

If an Officer whose signature is on a Convertible Preferred Stock certificate no longer holds that office at the time the Transfer Agent countersigns and registers the Convertible Preferred Stock certificate, the Convertible Preferred Stock certificate shall be valid nevertheless.

A Convertible Preferred Stock certificate shall not be valid until an authorized signatory of the Transfer Agent signs the Convertible Preferred Stock certificate by manual signature. The signature shall be conclusive evidence that the Convertible Preferred Stock certificate has been countersigned and registered under this Designating Resolution.

The Transfer Agent shall countersign, register and deliver certificates of Convertible Preferred Stock for original issue upon a written order of the Corporation signed by two Officers or by an Officer and an Assistant Treasurer of the Corporation. Such order shall specify the number of shares of Convertible Preferred Stock to be countersigned and registered and the date on which the original issue of the Convertible Preferred Stock is to be countersigned and registered.

The Transfer Agent may appoint a countersignature and registration agent reasonably acceptable to the Corporation to countersign and register the certificates for the Convertible Preferred Stock. Unless limited by the terms of such appointment, a countersignature and registration agent may countersign and register certificates for the Convertible Preferred Stock whenever the Transfer Agent may do so. Each reference in this Designating Resolution to countersignature and registration by the Transfer Agent includes countersignature and registration by such agent. A countersignature and registration agent has the same rights as the Transfer Agent or agent for service of notices and demands.

4. Transfer and Exchange.

(a) Transfer and Exchange of Certificated Convertible Preferred Stock. When Certificated Convertible Preferred Stock is presented to the Transfer Agent with a request to register the transfer of such Certificated Convertible Preferred Stock or to exchange such Certificated Convertible Preferred Stock for an equal number of shares of Certificated Convertible Preferred Stock, the Transfer Agent shall register the transfer or make the exchange as requested if its reasonable requirements for such transaction are met; provided, however, that the Certificated Convertible Preferred Stock surrendered for transfer or exchange shall be duly endorsed or accompanied by a written instrument of transfer in form reasonably satisfactory to the Corporation and the Transfer Agent, duly executed by the holder thereof or its attorney duly authorized in writing.

(b) Restrictions on Transfer of Certificated Convertible Preferred Stock for a Beneficial Interest in Global Convertible Preferred Stock. Certificated Convertible Preferred Stock may not be exchanged for a beneficial interest in Global Convertible Preferred Stock except upon satisfaction of the requirements set forth below. Upon receipt by the Transfer Agent of Certificated Convertible Preferred Stock, duly endorsed or accompanied by appropriate instruments of transfer, in form reasonably

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satisfactory to the Corporation and the Transfer Agent, together with written instructions directing the Transfer Agent to make, or to direct DTC to make, an adjustment on its books and records with respect to such Global Convertible Preferred Stock to reflect an increase in the number of shares of Convertible Preferred Stock represented by the Global Convertible Preferred Stock, then the Transfer Agent shall cancel such Certificated Convertible Preferred Stock and cause, or direct DTC to cause, in accordance with the standing instructions and procedures existing between DTC and the Transfer Agent, the number of shares of Convertible Preferred Stock represented by the Global Convertible Preferred Stock to be increased accordingly. If no Global Convertible Preferred Stock is then outstanding, the Corporation shall issue and the Transfer Agent shall countersign and register, upon written order of the Corporation in the form of an Officers’ certificate, a new Global Convertible Preferred Stock representing the appropriate number of shares.

(c) Transfer and Exchange of Global Convertible Preferred Stock. The transfer and exchange of Global Convertible Preferred Stock or beneficial interests therein shall be effected through DTC, in accordance with this Designating Resolution (including applicable restrictions on transfer set forth herein, if any) and the procedures of DTC therefor.

(d) Transfer of a Beneficial Interest in Global Convertible Preferred Stock for Certificated Convertible Preferred Stock.

(i) Any Person having a beneficial interest in Convertible Preferred Stock may upon request, but only with the consent of the Corporation, exchange such beneficial interest for Certificated Convertible Preferred Stock representing the same number of shares of Convertible Preferred Stock. Upon receipt by the Transfer Agent of written instructions or such other form of instructions as is customary for DTC from DTC or its nominee on behalf of any Person having a beneficial interest in Global Convertible Preferred Stock, then, the Transfer Agent or DTC, at the direction of the Transfer Agent, shall cause, in accordance with the standing instructions and procedures existing between DTC and the Transfer Agent, the number of shares of Convertible Preferred Stock represented by Global Convertible Preferred Stock to be reduced on its books and records and, following such reduction, the Corporation shall execute and the Transfer Agent shall countersign, register and deliver to the transferee Certificated Convertible Preferred Stock.

(ii) Certificated Convertible Preferred Stock issued in exchange for a beneficial interest in a Global Convertible Preferred Stock pursuant to this paragraph O.3(d) shall be registered in such names and in such authorized denominations as DTC, pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Transfer Agent. The Transfer Agent shall deliver such Certificated Convertible Preferred Stock to the persons or entities in whose names such Convertible Preferred Stock are so registered in accordance with the instructions of DTC.

(e) Restrictions on Transfer and Exchange of Global Convertible Preferred Stock. Notwithstanding any other provisions of this Designating Resolution (other than the provisions set forth in paragraph O.3(d)), Global Convertible Preferred Stock may not be transferred as a whole except by DTC to a nominee of DTC or by a nominee of DTC to DTC or another nominee of DTC or by DTC or any such nominee to a successor depository or a nominee of such successor depository.

(f) Countersignature and Registration of Certificated Convertible Preferred Stock. If at any time:

(i) DTC notifies the Corporation that DTC is unwilling or unable to continue as depository for the Global Convertible Preferred Stock and a successor depository for the Global Convertible Preferred Stock is not appointed by the Corporation within 90 days after delivery of such notice;

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(ii) DTC ceases to be a clearing agency registered under the Exchange Act and a successor depository for the Global Convertible Preferred Stock is not appointed by the Corporation within 90 days; or

(iii) the Corporation, in its sole discretion, notifies the Transfer Agent in writing that it elects to cause the issuance of Certificated Convertible Preferred Stock under this Designating Resolution;

then the Corporation shall execute, and the Transfer Agent, upon receipt of a written order of the Corporation signed by two Officers or by an Officer and an Assistant Treasurer of the Corporation requesting the countersignature, registration and delivery of Certificated Convertible Preferred Stock to the Persons designated by the Corporation, shall countersign, register and deliver Certificated Convertible Preferred Stock equal to the number of shares of Convertible Preferred Stock represented by the Global Convertible Preferred Stock, in exchange for such Global Convertible Preferred Stock.

(g) Cancellation or Adjustment of Global Convertible Preferred Stock. At such time as all beneficial interests in Global Convertible Preferred Stock have either been exchanged for Certificated Convertible Preferred Stock, converted or canceled, such Global Convertible Preferred Stock shall be returned to DTC for cancellation or retained and canceled by the Transfer Agent. At any time prior to such cancellation, if any beneficial interest in Global Convertible Preferred Stock is exchanged for Certificated Convertible Preferred Stock, converted or canceled, the number of shares of Convertible Preferred Stock represented by such Global Convertible Preferred Stock shall be reduced and an adjustment shall be made on the books and records of the Transfer Agent with respect to such Global Convertible Preferred Stock, by the Transfer Agent or DTC, to reflect such reduction.

(h) Obligations with Respect to Transfers and Exchanges of Convertible Preferred Stock.

(i) To permit registrations of transfers and exchanges, the Corporation shall execute and the Transfer Agent shall countersign and register Certificated Convertible Preferred Stock and Global Convertible Preferred Stock as required pursuant to the provisions of this paragraph O.3.

(ii) All Certificated Convertible Preferred Stock and Global Convertible Preferred Stock issued upon any registration of transfer or exchange of Certificated Convertible Preferred Stock or Global Convertible Preferred Stock shall be the valid obligations of the Corporation, entitled to the same benefits under this Designating Resolution as the Certificated Convertible Preferred Stock or Global Convertible Preferred Stock surrendered upon such registration of transfer or exchange.

(iii) Prior to due presentment for registration of transfer of any shares of Convertible Preferred Stock, the Transfer Agent and the Corporation may deem and treat the Person in whose name such shares of Convertible Preferred Stock are registered as the absolute owner of such Convertible Preferred Stock and neither the Transfer Agent nor the Corporation shall be affected by notice to the contrary.

(iv) No service charge shall be made to a holder of Convertible Preferred Stock for any registration of transfer or exchange upon surrender of any Convertible Preferred Stock certificate or common stock certificate of the Corporation at the office of the Transfer Agent maintained for that purpose. However, the Corporation may require payment of a sum sufficient to cover any tax or other governmental charge that may be imposed in connection with any registration of transfer or exchange of Convertible Preferred Stock certificates or common stock certificates of the Corporation.

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(i) No Obligation of the Transfer Agent.

(i) The Transfer Agent shall have no responsibility or obligation to any beneficial owner of Global Convertible Preferred Stock, a member of or a participant in, DTC or any other Person with respect to the accuracy of the records of DTC or its nominee or of any participant or member thereof, with respect to any ownership interest in the Convertible Preferred Stock or with respect to the delivery to any participant, member, beneficial owner or other Person (other than DTC) of any notice or the payment of any amount, under or with respect to such Global Convertible Preferred Stock. All notices and communications to be given to the holders of the Convertible Preferred Stock and all payments to be made to holders under the Convertible Preferred Stock shall be given or made only to the holders (which shall be DTC or its nominee in the case of the Global Convertible Preferred Stock). The rights of beneficial owners in any Global Convertible Preferred Stock shall be exercised only through DTC subject to the applicable rules and procedures of DTC. The Transfer Agent may rely and shall be fully protected in relying upon information furnished by DTC with respect to its members, participants and any beneficial owners.

(ii) The Transfer Agent shall have no obligation or duty to monitor, determine or inquire as to compliance with any restrictions on transfer imposed under this Designating Resolution or under applicable law with respect to any transfer of any interest in any Convertible Preferred Stock (including any transfers between or among DTC participants, members or beneficial owners in any Global Convertible Preferred Stock) other than to require delivery of such certificates and other documentation or evidence as are expressly required by, and to do so if and when expressly required by, the terms of this Designating Resolution, and to examine the same to determine substantial compliance as to form with the express requirements hereof.

5. Replacement Certificates. If any of the Convertible Preferred Stock certificates shall be mutilated, lost, stolen or destroyed, the Corporation shall issue, in exchange and in substitution for and upon cancellation of the mutilated Convertible Preferred Stock certificate, or in lieu of and substitution for the Convertible Preferred Stock certificate lost, stolen or destroyed, a new Convertible Preferred Stock certificate of like tenor and representing an equivalent amount of shares of Convertible Preferred Stock, but only upon receipt of evidence of such loss, theft or destruction of such Convertible Preferred Stock certificate and indemnity, if requested, satisfactory to the Corporation and the Transfer Agent.

6. Temporary Certificates. Until definitive Convertible Preferred Stock certificates are ready for delivery, the Corporation may prepare and the Transfer Agent shall countersign temporary Convertible Preferred Stock certificates. Temporary Convertible Preferred Stock certificates shall be substantially in the form of definitive Convertible Preferred Stock certificates but may have variations that the Corporation considers appropriate for temporary Convertible Preferred Stock certificates. Without unreasonable delay, the Corporation shall prepare and the Transfer Agent shall countersign definitive Convertible Preferred Stock certificates and deliver them in exchange for temporary Convertible Preferred Stock certificates.

7. Cancellation. The Transfer Agent and no one else shall cancel and destroy all Convertible Preferred Stock certificates surrendered for transfer, exchange, replacement or cancellation and deliver a certificate of such destruction to the Corporation unless the Corporation directs the Transfer Agent to deliver canceled Convertible Preferred Stock certificates to the Corporation. The Corporation may not issue new Convertible Preferred Stock certificates to replace Convertible Preferred Stock certificates to the extent they evidence Convertible Preferred Stock which the Corporation has purchased or otherwise acquired.

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P. OTHER PROVISIONS.

1. With respect to any notice to a holder of shares of Convertible Preferred Stock required to be provided hereunder, neither failure to mail such notice, nor any defect therein or in the mailing thereof, to any particular holder shall affect the sufficiency of the notice or the validity of the proceedings referred to in such notice with respect to the other holders or affect the legality or validity of any distribution, rights, warrant, reclassification, consolidation, merger, conveyance, transfer, dissolution, liquidation or winding-up, or the vote upon any such action. Any notice which was mailed in the manner herein provided shall be conclusively presumed to have been duly given whether or not the holder receives the notice.

2. Shares of Convertible Preferred Stock that have been issued and reacquired in any manner, including shares of Convertible Preferred Stock purchased or redeemed or exchanged or converted, shall (upon compliance with any applicable provisions of the laws of the State of Texas) have the status of authorized but unissued shares of Preferred Stock of the Corporation undesignated as to series and may be designated or redesignated and issued or reissued, as the case may be, as part of any series of Preferred Stock of the Corporation; provided that any issuance of such shares as Convertible Preferred Stock must be in compliance with the terms hereof.

3. The shares of Convertible Preferred Stock shall be issuable only in whole shares.

4. All notice periods referred to herein shall commence on the date of the mailing of the applicable notice. Notice to any holder of the Convertible Preferred Stock shall be given to the registered address set forth in the Corporation’s records for such holder, or for Global Convertible Preferred Stock, to the Depository in accordance with its procedures.

5. Any payments required to be made hereunder on any day that is not a Business Day shall be made on the next succeeding Business Day without interest or additional payment for such delay. Any actions required to be made hereunder on any day that is not a Business Day shall be taken on the next succeeding Business Day.

6. Holders of Convertible Preferred Stock shall not be entitled to any preemptive rights to acquire additional capital stock of the Corporation.

7. Notwithstanding any provision herein to the contrary, in accordance with paragraphs G, H, I, J or M, the procedures for conversion and voting of shares of Convertible Preferred Stock represented by Global Convertible Preferred Stock will be governed by arrangements among DTC, its participants and Persons that may hold beneficial interests through such participants designed to permit settlement without the physical movement of certificates. Payments, transfers, deliveries, exchanges and other matters relating to beneficial interests in Global Convertible Preferred Stock certificates may be subject to various policies and procedures adopted by DTC from time to time.

8. The Corporation shall not take any voluntary action that would increase the Conversion Rate of the Convertible Preferred Stock pursuant to the any provision of paragraph G.4 without complying, if applicable, with the shareholder approval rules of the Nasdaq Stock Market (including Market Rule 5635, which requires shareholder approval of certain issuances of the Corporation’s ordinary shares) or any stock exchange on which the Corporation’s common stock is listed at the relevant time.

9. Whether or not the Corporation is required to file reports with the Commission, if any shares of Convertible Preferred Stock are outstanding, the Corporation will file with the Commission all such reports and other information as the Corporation would be required to file and on or prior to the dates such reports would be required to be filed with the Commission by Section 13(a) or 15(d) under the Exchange Act.

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BE IT FURTHER RESOLVED, that the appropriate officers of the Corporation are hereby authorized, empowered and directed, for and on behalf and in the name of the Corporation, to execute a statement of resolutions substantially to the effect as set forth above (the “Statement of Resolutions”) and to cause the Statement of Resolutions to be delivered in duplicate to the Secretary of State of the State of Texas for filing therewith pursuant to the provisions of Article 2.13 of the Texas Business Corporation Act.

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Dated: September 28, 2009.

ATP OIL & GAS CORPORATION
By:	/s/ T. Paul Bulmahn
	Name:	T. Paul Bulmahn
	Title:	Chief Executive Officer

ATTACHMENT 1

FORM OF 8% CONVERTIBLE PREFERRED STOCK CERTIFICATE

(attached as Exhibit 4.1 to this Current Report on Form 8-K)

EX-4.1

Exhibit 4.1

Exhibit 4.1

INCORPORATED UNDER THE LAWS OF THE STATE OF TEXAS

PREFERRED STOCK

PC

ATP OIL & GAS CORPORATION

PREFERRED STOCK

CUSIP 00208J 70 2

SEE REVERSE FOR CERTAIN DEFINITIONS

THIS CERTIFIES THAT

IS THE OWNER OF

FULLY PAID AND NON-ASSESSABLE SHARES OF 8% CONVERTIBLE PERPETUAL PREFERRED STOCK, PAR VALUE $.001 PER SHARE, OF

ATP OIL & GAS CORPORATION transferable on the books of the Corporation by the holder hereof in person or by duly authorized attorney upon surrender of this certificate properly endorsed. This certificate is not valid until countersigned by the Transfer Agent and registered by the Registrar.

Witness the facsimile seal of the Corporation and the facsimile signatures of its duly authorized officers.

Dated:

CHAIRMAN OF THE BOARD

SECRETARY

COUNTERSIGNED AND REGISTERED:

AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC

(NEW YORK, NY) TRANSFER AGENT AND REGISTRAR

BY

AUTHORIZED SIGNATURE

ABnote North America

711 ARMSTRONG LANE

COLUMBIA, TENNESSEE 38401

(931) 388-3003

SALES: HOLLY GRONER 931-490-7660

PROOF OF: SEPTEMBER 28, 2009

ATP OIL & GAS CORPORATION

TSB 00336

OPERATOR: AP

NEW

PLEASE INITIAL THE APPROPRIATE SELECTION FOR THIS PROOF: OK AS IS OK WITH CHANGES MAKE CHANGES AND SEND ANOTHER PROOF Colors Selected for Printing: Intaglio prints in SC-20 DARK BROWN.

COLOR: This proof was printed from a digital file or artwork on a graphics quality, color laser printer. It is a good representation of the color as it will appear on the final product. However, it is not an exact color rendition, and the final printed product may appear slightly different from the proof due to the difference between the dyes and printing ink.

A full statement of the designations, preferences, limitations and relative rights of the shares of each class of stock of the Corporation authorized to be issued is set forth in the Restated Articles of Incorporation of the Corporation, as amended, on file in the Office of the Secretary of State of the State of Texas. The Restated Articles of Incorporation of the Corporation, as amended, on file in the Office of the Secretary of State of the State of Texas, deny the preemptive right of shareholders to acquire unissued or treasury shares of the Corporation. The Corporation shall furnish a copy of its Restated Articles of Incorporation, as amended, to the record holder of this Certificate without charge upon written request to the Secretary of the Corporation at its principal place of business in Houston, Texas.

THIS SECURITY (OR ITS PREDECESSOR) WAS ORIGINALLY ISSUED IN A TRANSACTION EXEMPT FROM REGISTRATION UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), AND THIS SECURITY AND ANY COMMON STOCK ISSUABLE UPON CONVERSION THEREOF MAY NOT BE OFFERED, SOLD OR OTHERWISE TRANSFERRED IN THE ABSENCE OF SUCH REGISTRATION OR AN APPLICABLE EXEMPTION THEREFROM. EACH PURCHASER OF THIS SECURITY IS HEREBY NOTIFIED THAT THE SELLER OF THIS SECURITY MAY BE RELYING ON THE EXEMPTION FROM THE PROVISIONS OF SECTION 5 OF THE SECURITIES ACT PROVIDED BY RULE 144A THEREUNDER.

THE HOLDER OF THIS SECURITY AGREES FOR THE BENEFIT OF THE CORPORATION THAT (A) THIS SECURITY AND THE COMMON STOCK ISSUABLE UPON CONVERSION HEREOF MAY BE OFFERED, RESOLD, PLEDGED OR OTHERWISE TRANSFERRED, ONLY (I) IN THE UNITED STATES TO A PERSON WHOM THE SELLER REASONABLY BELIEVES IS A QUALIFIED INSTITUTIONAL BUYER (AS DEFINED IN RULE 144A UNDER THE SECURITIES ACT) IN A TRANSACTION MEETING THE REQUIREMENTS OF RULE 144A, (II) PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT PROVIDED BY RULE 144 THEREUNDER (IF AVAILABLE) OR (III) PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT, IN EACH OF CASES (I) THROUGH (III) IN ACCORDANCE WITH ANY APPLICABLE SECURITIES LAWS OF ANY STATE OF THE UNITED STATES, AND (B) THE HOLDER WILL, AND EACH SUBSEQUENT HOLDER IS REQUIRED TO, NOTIFY ANY PURCHASER OF THIS SECURITY OR ANY COMMON STOCK ISSUABLE UPON CONVERSION THEREOF FROM IT OF THE RESALE RESTRICTIONS REFERRED TO IN (A) ABOVE. IN ANY CASE, THE HOLDER HEREOF WILL NOT, DIRECTLY OR INDIRECTLY, ENGAGE IN ANY HEDGING TRANSACTIONS WITH REGARD TO THIS SECURITY EXCEPT AS PERMITTED UNDER THE SECURITIES ACT.

THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO THE PROVISIONS OF A STATEMENT OF RESOLUTIONS ESTABLISHING AND DESIGNATING THE CONVERTIBLE PREFERRED STOCK OF THE CORPORATION. THESE SECURITIES MAY NOT BE TRANSFERRED EXCEPT IN ACCORDANCE WITH SUCH STATEMENT OF RESOLUTIONS.

THIS CERTIFICATE IS IN GLOBAL FORM AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY (“DTC”) OR A NOMINEE THEREOF. THIS CERTIFICATE MAY NOT BE TRANSFERRED EXCEPT AS A WHOLE BY DTC TO A NOMINEE OF DTC OR BY A NOMINEE OF DTC TO DTC OR ANOTHER NOMINEE OF DTC OR BY ANY SUCH NOMINEE TO A SUCCESSOR OF DTC OR A NOMINEE OF SUCH SUCCESSOR DEPOSITORY.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF DTC TO THE CORPORATION OR THE TRANSFER AGENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN

The following abbreviations, when used in the inscription on the face of this certificate, shall be construed as though they were written out in full according to applicable laws or regulations:

TEN COM – as tenants in common

TEN ENT – as tenants by the entireties

JT TEN – as joint tenants with right of survivorship and not as tenants in common

UNIF GIFT MIN ACT– Custodian

(Cust) (Minor)

Under Uniform Gifts to Minors

Act (State)

Additional abbreviations may also be used though not in the above list.

ASSIGNMENT

For Value Received, hereby sell, assign and transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER IDENTIFYING NUMBER OF ASSIGNEE

PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS, INCLUDING POSTAL ZIP CODE, OF ASSIGNEE

Shares of the Common Stock represented by the within Certificate, and do hereby irrevocably constitute and appoint

Attorney to transfer the said shares on the books of the within-named Corporation, with full power of substitution in the premises.

Dated

X

X

NOTICE: THE SIGNATURE(S) TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.

Signature(s) Guaranteed

By

THE SIGNATURE(S) SHOULD BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS, STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE 17Ad-15.

ABnote North America

711 ARMSTRONG LANE

COLUMBIA, TENNESSEE 38401

(931) 388-3003

SALES: HOLLY GRONER 931-490-7660

PROOF OF: SEPTEMBER 28, 2009

ATP OIL & GAS CORPORATION

TSB 00336

OPERATOR: AP

NEW

PLEASE INITIAL THE APPROPRIATE SELECTION FOR THIS PROOF: OK AS IS OK WITH CHANGES MAKE CHANGES AND SEND ANOTHER PROOF

EX-10.1

Exhibit 10.1

EXECUTION COPY

1,250,000

ATP Oil & Gas Corporation

8.00%Convertible Perpetual Preferred Stock

PURCHASE AGREEMENT

September 23, 2009

CREDIT SUISSE SECURITIES (USA) LLC

J.P. MORGAN SECURITIES INC.

As Representatives of the several Purchasers

c/o Credit Suisse Securities (USA) LLC (“Credit Suisse”)

Eleven Madison Avenue,

New York, N.Y. 10010-3629

Dear Sirs:

1. Introductory. ATP Oil & Gas Corporation, a Texas corporation (the “Company”), agrees with the several initial purchasers named in Schedule A hereto (the “Purchasers”), for whom you are acting as the representatives (the “Representatives”), subject to the terms and conditions stated herein, to issue and sell to the several Purchasers 1,250,000 shares of its 8.00% Convertible Perpetual Preferred Stock (the “Firm Securities”) and also proposes to grant to the Purchasers an option, exercisable from time to time by the Representatives, to purchase an aggregate of up to an additional 350,000 shares (“Optional Securities”) of its 8.00% Convertible Perpetual Preferred Stock. The Firm Securities and the Optional Securities which the Purchasers may elect to purchase pursuant to Section 3 hereof are herein collectively called the “Offered Securities”.

The Offered Securities will be convertible, subject to certain conditions set forth in the Statement of Resolutions establishing the Offered Securities, at the option of the holder for shares of common stock, par value $0.001 per share, of the Company (the “Common Stock”), in accordance with the terms of the Offered Securities.

The Company hereby agrees with the several Purchasers as follows:

1. Representations and Warranties of the Company. The Company represents and warrants to, and agrees with, the several Purchasers that:

(a) Offering Circulars; Certain Defined Terms. The Company has prepared or will prepare a Preliminary Offering Circular and a Final Offering Circular.

For purposes of this Agreement:

“Applicable Time” means 8:00 p.m. (New York City time) on the date of this Agreement.

“Closing Date” has the meaning set forth in Section 3 hereof.

“Commission” means the Securities and Exchange Commission.

“Exchange Act” means the United States Securities Exchange Act of 1934.

“Final Offering Circular” means the final offering circular (including all documents incorporated by reference therein) relating to the Offered Securities to be offered by the Purchasers that discloses the offering price and other final terms of the Offered Securities and is dated as of the date of this Agreement (even if finalized and issued subsequent to the date of this Agreement).

“Free Writing Communication” means a written communication (as such term is defined in Rule 405) that constitutes an offer to sell or a solicitation of an offer to buy the Offered Securities and is made by means other than the Preliminary Offering Circular or the Final Offering Circular.

“General Disclosure Package” means the Preliminary Offering Circular together with any Issuer Free Writing Communication existing at the Applicable Time and the information in which is intended for general distribution to prospective investors, as evidenced by its being specified in Schedule B hereto.

“Issuer Free Writing Communication” means a Free Writing Communication prepared by or on behalf of the Company, used or referred to by the Company or containing a description of the final terms of the Offered Securities or of their offering, in the form retained in the Company’s records.

“Preliminary Offering Circular” means the preliminary offering circular (including all documents incorporated by reference therein), dated September 22, 2009, relating to the Offered Securities to be offered by the Purchasers.

“Rules and Regulations” means the rules and regulations of the Commission.

“Securities Act” means the United States Securities Act of 1933.

“Securities Laws” means, collectively, the Sarbanes-Oxley Act of 2002 (“Sarbanes-Oxley”), the Act, the Exchange Act, the Rules and Regulations, the auditing principles, rules, standards and practices applicable to auditors of “issuers” (as defined in Sarbanes-Oxley) promulgated or approved by the Public Company Accounting Oversight Board and, as applicable, the rules of the New York Stock Exchange and the NASDAQ Stock Market (“Exchange Rules”).

“Supplemental Marketing Material” means any Issuer Free Writing Communication other than any Issuer Free Writing Communication specified in Schedule B hereto.Supplemental Marketing Materials include, but are not limited to, any Issuer Free Writing Communication listed on Schedule C hereto.

“Underlying Shares” means shares of Common Stock into which the Offered Securities are convertible or shares of Common Stock that may be issued as dividends on the Offered Securities or may otherwise be issued in respect of the Offered Securities.

Unless otherwise specified, a reference to a “rule” is to the indicated rule under the Securities Act.

(b) Disclosure. As of the date of this Agreement, the Final Offering Circular does not, and as of each Closing Date, the Final Offering Circular will not include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. At the Applicable Time neither (i) the General Disclosure Package nor (ii) any individual Supplemental Marketing Material, when considered together with the General Disclosure Package, included any untrue statement of a material fact or omitted to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding two sentences do not apply to statements in or omissions from the Preliminary or Final Offering Circular, the General Disclosure Package or any Supplemental Marketing Material based upon written information furnished to the Company by any Purchaser through the Representatives specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(b) hereof. Except as disclosed in the General Disclosure Package, on the date of this Agreement, the Company’s Annual Report on Form 10-K

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most recently filed with the Commission and all subsequent reports (collectively, the “Exchange Act Reports”) which have been filed by the Company with the Commission or sent to shareholders pursuant to the Exchange Act do not include any untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading. Such documents, when they were filed with the Commission, conformed in all material respects to the requirements of the Exchange Act and the Rules and Regulations.

(c) Good Standing of the Company. The Company has been duly incorporated and is existing and in good standing under the laws of the State of Texas, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package and the Final Offering Circular; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification.

(d) Subsidiaries. Each subsidiary of the Company has been duly incorporated and is existing and in good standing under the laws of the jurisdiction of its incorporation, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package and the Final Offering Circular; and each subsidiary of the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so qualify would not have, individually or in the aggregate, a material adverse effect on the business, financial position, or results of operations of the Company and its subsidiaries taken as a whole or on the performance by the Company of its obligations under this Agreement (“Material Adverse Effect”); all of the issued and outstanding capital stock of each subsidiary of the Company has been duly authorized and validly issued and is fully paid and nonassessable; and, except as disclosed in the General Disclosure Package and the Final Offering Circular, the capital stock of each subsidiary owned by the Company, directly or through subsidiaries, is owned free from liens, encumbrances and defects.

(e) Offered Securities. The Offered Securities and all other outstanding shares of capital stock of the Company have been duly authorized; and when the Offered Securities are delivered and paid for pursuant to this Agreement on each Closing Date, such Offered Securities will have been validly issued, fully paid and nonassessable, will conform to the information in the General Disclosure Package and will conform to the description of such Offered Securities contained in the Final Offering Circular; and the shareholders of the Company have no preemptive rights with respect to the Offered Securities; none of the outstanding shares of capital stock of the Company are or will have been issued in violation of any preemptive or similar rights of any security holder; and the authorized equity capitalization of the Company is as set forth in the General Disclosure Package and the Final Offering Circular.

(f) Underlying Shares. When the Offered Securities are delivered and paid for pursuant to this Agreement on each Closing Date, such Offered Securities will be convertible into the Underlying Shares of the Company in accordance with their terms; the Underlying Shares initially issuable upon conversion of such Offered Securities have been duly authorized and reserved for issuance upon such conversion and will conform to the information in the General Disclosure Package and will conform to the description of such Underlying Shares contained in the Final Offering Circular; all outstanding shares of capital stock of the Company are, and when issued upon conversion of the Offered Securities the Underlying Shares will be, validly issued, fully paid and nonassessable; and the shareholders of the Company have no preemptive rights with respect to the issuance of the Underlying Shares upon the conversion of the Offered Securities.

(g) No Finder’s Fee. Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against the Company or any of its subsidiaries or any Purchaser for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Offered Securities.

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(h) Absence of Further Requirements. No consent, approval, authorization, order, license, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of this Agreement, the issuance and sale of the Offered Securities and the Underlying Shares and the consummation of the transactions contemplated by this Agreement and described in the General Disclosure Package and Final Offering Circular.

(i) Stock Options. With respect to the stock options (the “Stock Options”) granted pursuant to the stock-based compensation plans of the Company and its subsidiaries (the “Company Stock Plans”), (A) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Code so qualifies, (B) each grant of a Stock Option was duly authorized no later than the date on which the grant of such Stock Option was by its terms to be effective (the “Grant Date”) by all necessary corporate action, including, as applicable, approval by the board of directors of the Company (or a duly constituted and authorized committee thereof) and any required shareholder approval by the necessary number of votes or written consents, and the award agreement governing such grant (if any) was duly executed and delivered by each party thereto, (C) each such grant was made in accordance with the terms of the Company Stock Plans, the Exchange Act and all other applicable laws and regulatory rules or requirements, including the rules of the Nasdaq Global Select Market and any other exchange on which Company securities are traded, and (D) each such grant was properly accounted for in accordance with generally accepted accounting principles in the financial statements (including the related notes) of the Company and disclosed in the Company’s filings with the Commission in accordance with the Exchange Act and all other applicable laws. The Company has not knowingly granted, and there is no and has been no policy or practice of the Company of granting, Stock Options prior to, or otherwise coordinating the grant of Stock Options with, the release or other public announcement of material information regarding the Company or its subsidiaries or their results of operations or prospects.

(j) Title to Real and Personal Property. Except as disclosed in the General Disclosure Package and the Final Offering Circular or such as in the aggregate does not now cause nor will it in the future cause a Material Adverse Effect, the Company and its subsidiaries have title to their properties as follows: (A) with respect to their wells (including leasehold interests and appurtenant personal property) and their non-producing oil and gas properties (including undeveloped locations on leases held by production and those leases not held by production), such title is valid and defensible and free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and restrictions, (B) with respect to their non-producing properties in exploration prospects, such title was investigated in accordance with customary industry procedures prior to the Company or its subsidiaries’ acquisition thereof; (C) with respect to their real property other than oil and gas interests, such title is good and marketable free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and restrictions; and (D) with respect to their personal property other than that appurtenant to its oil and gas interests, such title is free and clear of all liens, security interests, pledges, charges, encumbrances, mortgages and restrictions. No real property owned, leased, licensed, or used by the Company or its subsidiaries lies in an area which is, or to the knowledge of the Company will be, subject to restrictions which would prohibit, and no statements of facts relating to the actions or inaction of another person or entity or his or its ownership, leasing, licensing, or use of any real or personal property exists or will exist which would prevent, the continued effective ownership, leasing, licensing, exploration, development or production or use of such real property in the business of the Company as presently conducted or as the General Disclosure Package or the Final Offering Circular indicates they contemplate conducting, except as disclosed in the General Disclosure Package and the Final Offering Circular or such as in the aggregate do not now cause and will not in the future reasonably be expected to cause a Material Adverse Effect.

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(k) Title to Intellectual Property. The Company and its subsidiaries own or possess, or can acquire on reasonable terms, adequate patents, patent rights, licenses, inventions, copyrights, know-how, confidential information, trademarks, service marks, trade names or other intellectual property (collectively, “Intellectual Property”) necessary to carry on the business now operated by them, except where the failure to own or possess, or have the ability to acquire on reasonable terms such Intellectual Property, would not reasonably be expected to cause, individually or in the aggregate, a Material Adverse Effect. Neither the Company nor any subsidiary has received any notice of any infringement of or conflict with asserted rights of others with respect to any Intellectual Property that if determined adversely to the Company would result in, individually or in the aggregate, a Material Adverse Effect.

(l) Absence of Defaults and Conflicts Resulting from Transaction. The execution, delivery and performance by the Company of each of this Agreement, the issuance and sale of the Offered Securities and the Underlying Shares and the consummation of the transactions contemplated by this Agreement and described in the General Disclosure Package and Final Offering Circular will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company or any of its subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject, (ii) result in any violation of the provisions of the charter or by-laws or similar organizational documents of the Company or any of its subsidiaries or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (i) and (iii) above, for any such conflict, breach, violation or default that would not, individually or in the aggregate, have a Material Adverse Effect.

(m) Absence of Existing Defaults and Conflicts. Neither the Company nor any of its subsidiaries is (i) in violation of its charter or by-laws or similar organizational documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any of the property or assets of the Company or any of its subsidiaries is subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (ii) and (iii) above, for any such default or violation that would not, individually or in the aggregate, have a Material Adverse Effect.

(n) Authorization of Agreement. The Company has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of this Agreement and the consummation by it of the transactions contemplated hereby has been duly and validly taken. This Agreement has been duly authorized, executed and delivered by the Company.

(o) Possession of Licenses and Permits. The Company and its subsidiaries possess all licenses, certificates, permits and other authorizations issued by the appropriate Federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the General Disclosure Package and the Final Offering Circular, except where the failure to so possess would not have, individually or in the aggregate, a Material Adverse Effect; except as described in the General Disclosure Package and the Final Offering Circular, the Company and its subsidiaries are in compliance with the terms and conditions of all such licenses, certificates, permits and authorizations, except where the failure to so comply would not have, individually or in the aggregate, a Material Adverse Effect; and except as described in the General Disclosure Package

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and the Final Offering Circular, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such license, certificate, permit or authorization which, individually or in the aggregate, if subject to an unfavorable decision, ruling or finding would result in a Material Adverse Effect.

(p) Absence of Labor Dispute. No labor disturbance by or dispute with employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent, and the Company is not aware of any existing or imminent labor disturbance by, or dispute with, the employees of any of its or its subsidiaries’ principal suppliers, contractors or customers, except as would not have a Material Adverse Effect.

(q) Environmental Laws. (A) The Company and its subsidiaries (1) are in compliance with any and all applicable Federal, state, local and foreign laws, rules, regulations, requirements, decisions, judgments, decrees, and orders relating to pollution or the protection of the environment, natural resources or human health or safety, including those relating to the generation, storage, treatment, use, handling, transportation, Release or threat of Release of Hazardous Materials (collectively, “Environmental Laws”), (2) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under applicable Environmental Laws to conduct their respective businesses, (3) have not received notice of any actual or potential liability under or relating to, or actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any Release or threat of Release of Hazardous Materials, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, (4) are not conducting or paying for, in whole or in part, any investigation, remediation or other corrective action pursuant to any Environmental Law at any location, and (5) are not a party to any order, decree or agreement that imposes any obligation or liability under any Environmental Law, except for any such matter as would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect, and (B) there are no costs or liabilities associated with Environmental Laws of or relating to the Company or its subsidiaries, except for any such matter as would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect; and (C) except as described in the General Disclosure Package and the Final Offering Circular, (1) there are no proceedings that are pending, or that are known to be contemplated, against the Company or any of its subsidiaries under any Environmental Laws in which a governmental entity is also a party, other than such proceedings regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed, and (2) the Company and its subsidiaries are not aware of any facts or issues regarding compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws, including the Release or threat of Release of Hazardous Materials, that could reasonably be expected to have a material effect on the capital expenditures, earnings or competitive position of the Company and its subsidiaries.

(r) Hazardous Materials. There has been no storage, generation, transportation, use, handling, treatment, Release or threat of Release of Hazardous Materials by, relating to or caused by the Company or any of its subsidiaries (or, to the knowledge of the Company and its subsidiaries, any other entity (including any predecessor) for whose acts or omissions the Company or any of its subsidiaries is or could reasonably be expected to be liable) at, on, under or from any property or facility now or previously owned, operated or leased by the Company or any of its subsidiaries, or at, on, under or from any other property or facility, in violation of any Environmental Laws or in a manner or amount or to a location that could reasonably be expected to result in any liability of the Company or any of its subsidiaries under any Environmental Law, except for any violation or liability which would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect. “Hazardous Materials” means any material, chemical, substance, waste, pollutant, contaminant, compound, mixture, or constituent thereof, in any form or amount, including petroleum (including crude oil or any fraction thereof) and petroleum products, natural gas, natural gas liquids, asbestos and asbestos containing materials, naturally occurring radioactive materials, brine, and drilling mud, regulated or which can give rise to liability under any Environmental Law. “Release” means any spilling, leaking, seepage,

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pumping, pouring, emitting, emptying, discharging, injecting, escaping, leaching, dumping, disposing, depositing, dispersing, or migrating in, into or through the environment, or in, into, from or through any building or structure

(s) Absence of Manipulation. Neither the Company nor any of its affiliates has, either alone or with one or more other persons, bid for or purchased for any account in which it or any of its affiliates had a beneficial interest any Offered Securities or attempted to induce any person to purchase any Offered Securities.

(t) Statistical and Market-Related Data. Any third-party statistical and market-related data included in a Preliminary Offering Circular, a Final Offering Circular, or any Issuer Free Writing Communication are based on or derived from sources that the Company believes to be reliable and accurate.

(u) Disclosure Controls. The Company and its subsidiaries maintain an effective system of “disclosure controls and procedures” (as defined in Rule 13a-15(e) of the Exchange Act) that complies with the requirements of the Exchange Act and that has been designed to ensure that information required to be disclosed by the Company in reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including controls and procedures designed to ensure that such information is accumulated and communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure. The Company and its subsidiaries have carried out evaluations of the effectiveness of their disclosure controls and procedures as required by Rule 13a-15 of the Exchange Act.

(v) Accounting Controls. The Company and its subsidiaries maintain systems of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of, their respective principal executive and principal financial officers, or persons performing similar functions, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, including, but not limited to, internal accounting controls sufficient to provide reasonable assurance that (A) transactions are executed in accordance with management’s general or specific authorizations; (B) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (C) access to assets is permitted only in accordance with management’s general or specific authorization; and (D) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as disclosed in the General Disclosure Package and the Final Offering Circular, the Company is not aware of (i) any significant deficiencies or material weaknesses in the design or operation of internal controls or (ii) any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting which are likely to adversely affect the Company’s ability to record, process, summarize and report financial information. The Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of: (1) all significant deficiencies and material weaknesses in the design or operation of internal controls over financial reporting which have adversely affected or are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information; and (2) any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting.

(w) Absence of Accounting Issues. A member of the Audit Committee has confirmed to the Chief Executive Officer, Chief Financial Officer or General Counsel that, except as set forth in the General Disclosure Package and the Final Offering Circular, the Audit Committee is not reviewing or investigating, and neither the Company’s independent auditors nor its internal

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auditors have recommended that the Audit Committee review or investigate, (A) adding to, deleting, changing the application of, or changing the Company’s disclosure with respect to, any of the Company’s material accounting policies; (B) any matter which could result in a restatement of the Company’s financial statements for any annual or interim period during the current or prior three fiscal years; or (C) any Internal Control Event.

(x) Litigation. Except as disclosed in the General Disclosure Package and the Final Offering Circular, there are no legal, governmental or regulatory investigations, actions, suits or proceedings pending to which the Company or any of its subsidiaries is or may be a party or to which any property of the Company or any of its subsidiaries is or may be the subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, would reasonably be expected to have a Material Adverse Effect; no such investigations, actions, suits or proceedings are threatened by any governmental or regulatory authority.

(y) Taxes. The Company and its subsidiaries have on a timely basis paid all Federal, state, local and foreign taxes and filed all tax returns required to be paid or filed through the date hereof (except in any case in which the failure to so file has not had and would not reasonably be expected to result in a Material Adverse Effect); and except as otherwise disclosed in the General Disclosure Package and the Final Offering Circular, there is no tax deficiency that has been, or could reasonably be expected to be, asserted against the Company or any of its subsidiaries or any of their respective properties or assets, except for any tax deficiency that is currently being contested in good faith or would not result in a Material Adverse Effect.

(z) Financial Statements. The financial statements (including the related notes thereto) of the Company and its consolidated subsidiaries included or incorporated by reference in the General Disclosure Package and the Final Offering Circular comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly the financial position of the Company and its consolidated subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; such financial statements have been prepared in conformity with generally accepted accounting principles applied on a consistent basis throughout the periods covered thereby, and any supporting schedules included or incorporated by reference in the General Disclosure Package and the Final Offering Circular present fairly the information required to be stated therein; and the other financial information included or incorporated by reference in the General Disclosure Package and the Final Offering Circular has been derived from the accounting records of the Company and its consolidated subsidiaries and presents fairly the information shown thereby.

(aa) No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the General Disclosure Package and the Final Offering Circular, (A) there has not been any material change in the capital stock (other than the issuance of shares of Common Stock upon exercise of stock options and warrants described as outstanding in, and the grant of options and awards under existing equity incentive plans described in, the General Disclosure Package and the Final Offering Circular), short-term debt or long-term debt of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development involving a prospective material adverse change, in or affecting the business, properties, management, financial position, shareholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole; (B) neither the Company nor any of its subsidiaries has entered into any transaction or agreement (whether or not in the ordinary course of business) that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole; and (C) neither the Company nor any of its subsidiaries has sustained any loss or interference with its business that is material to the Company and its subsidiaries taken as a whole and that is either from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority, except in each case as otherwise disclosed in the General Disclosure Package and the Final Offering Circular.

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(bb) Investment Company Act. The Company is not and, after giving effect to the offering and sale of the Offered Securities and the application of the proceeds thereof as described in the General Disclosure Package and the Final Offering Circular, will not be required to register as an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Investment Company Act”).

(cc) Regulations T, U, X. The application of the proceeds received by the Company from the issuance, sale and delivery of the Offered Securities as described in the General Disclosure Package and the Final Offering Circular will not violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

(dd) Ratings. No “nationally recognized statistical rating organization” as such term is defined for purposes of Rule 436(g)(2) (i) has imposed (or has informed the Company that it is considering imposing) any condition (financial or otherwise) on the Company’s retaining any rating assigned to the Company or any securities of the Company or (ii) has indicated to the Company that it is considering any of the actions described in Section 7(c)(ii) hereof.

(ee) Class of Securities Not Listed. No securities of the same class (within the meaning of Rule 144A(d)(3)) as the Offered Securities are listed on any national securities exchange registered under Section 6 of the Exchange Act or quoted in a U.S. automated inter-dealer quotation system.

(ff) No Registration. The offer and sale of the Offered Securities in the manner contemplated by this Agreement will be exempt from the registration requirements of the Securities Act by reason of Section 4(2) thereof, Regulation D thereunder and Regulation S thereunder.

(gg) No General Solicitation; No Directed Selling Efforts. Neither the Company, nor any of its affiliates, nor any person acting on its or their behalf (i) has, within the six-month period prior to the date hereof, offered or sold in the United States or to any U.S. person (as such terms are defined in Regulation S under the Securities Act) the Offered Securities or any security of the same class or series as the Offered Securities or (ii) has offered or will offer or sell the Offered Securities (A) in the United States by means of any form of general solicitation or general advertising within the meaning of Rule 502(c) or (B) with respect to any such securities sold in reliance on Rule 903 of Regulation S (“Regulation S”) under the Securities Act, by means of any directed selling efforts within the meaning of Rule 902(c) of Regulation S. The Company, its affiliates and any person acting on its or their behalf have complied and will comply with the offering restrictions requirement of Regulation S. The Company has not entered and will not enter into any contractual arrangement with respect to the distribution of the Offered Securities except for this Agreement.

(hh) Use of Proceeds. The proceeds to the Company from the offering of the Offered Securities will not be used to purchase or carry any security.

(ii) Reporting Status. The Company is subject to Section 13 or 15(d) of the Exchange Act.

(jj) Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, including business interruption insurance, which insurance is in amounts and insures against such losses and risks as are customary for the businesses in which they are engaged; all such policies insuring the Company

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and its subsidiaries are in full force and effect; and neither the Company nor any of its subsidiaries has received notice from any insurer or agent of such insurer that it will not be able to renew insurance coverage as and when such coverage expires or to obtain coverage acceptable to the Company at reasonable cost from similar insurers as may be necessary to continue its business.

(kk) Compliance with ERISA. The minimum funding standard under Section 302 of the Employee Retirement Income Security Act of 1974, as amended, and the regulations and published interpretations thereunder (“ERISA”), has been satisfied by each “pension plan” (as defined in Section 3(2) of ERISA) which has been established or maintained by the Company, and the trust forming part of each such plan which is intended to be qualified under Section 401 of the Internal Revenue Code of 1986, as amended (the “Code”), is so qualified; each of the Company and each of its subsidiaries has fulfilled its obligations, if any, under Section 515 of ERISA; neither the Company nor any of its subsidiaries maintains and is required to contribute to a “welfare plan” (as defined in Section 3(1) of ERISA) which provides retiree or other post-employment welfare benefits or insurance coverage (other than “continuation coverage” (as defined in Section 602 of ERISA)); each pension plan and welfare plan established or maintained by the Company and/or one of the subsidiaries is in compliance with the currently applicable provisions of ERISA, except where the failure to comply would not cause a Material Adverse Effect; no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any pension plan or welfare plan (excluding transactions effected pursuant to statutory or administrative exemption) that could reasonably be expected to result in a material liability to the Company or its subsidiaries; and neither the Company nor any of its subsidiaries has incurred or could reasonably be expected to incur any withdrawal liability under Section 4201 of ERISA, any liability under Section 4062, 4063, or 4064 of ERISA, or any other liability under Title IV of ERISA.

(ll) Reserve Report Data. The oil and gas reserve estimates of the Company contained or incorporated by reference into the General Disclosure Package and the Final Offering Circular have been prepared by (A) Ryder Scott Company, L.P., (B) Collarini Associates and (C) DeGolyer & MacNaughton (collectively, the “Engineers”), and the Company has no reason to believe that such estimates do not fairly reflect the oil and gas reserves of the Company at the dates indicated. The information underlying the estimates of the reserves of the Company and its subsidiaries supplied by the Company to the Engineers, for the purposes of preparing the reserve reports of Company and its subsidiaries referenced in the General Disclosure Package and the Final Offering Circular (the “Reserve Reports”), was true and correct in all material respects on the date of each such Reserve Report; the estimates of future capital expenditures and other future exploration and development costs supplied to the Engineers were prepared in good faith and with a reasonable basis; the information provided to the Engineers was prepared in good faith and with a reasonable basis. Other than production of the reserves in the ordinary course of business and intervening product price fluctuations described in the General Disclosure Package and the Final Offering Circular, the Company is not aware of any facts or circumstances that would cause a Material Adverse Change in the reserves or the present value of future net cash flows therefrom as described in the General Disclosure Package and the Final Offering Circular. Each of the Engineers is an independent reserve engineer with respect to the Company and its subsidiaries.

(mm) Related Party Transactions. All business relationships or related-party transactions involving the Company or any of its subsidiaries or any of their respective directors, managers, executive officers, nominees for election as director, manager or executive officer, any security holder, member interest holder or partnership interest holder, each as applicable, who is known to the Company or any of its subsidiaries to own of record or beneficially more than five percent of any class of the Company’s or any of its subsidiaries’ voting securities or interests, as applicable, any member of the immediate family of the foregoing persons, or any other person, required to be disclosed pursuant to the requirements of Item 404 of Regulation S-K under the Securities Act, are accurately described in the General Disclosure Package and the Final Offering Circular, and all other related-party transactions required to be disclosed pursuant to the requirements of Item 404 of Regulation S-K under the Securities Act have been accurately described in the General Disclosure Package.

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(nn) Independent Accountants. PricewaterhouseCoopers LLP, who have certified certain financial statements of the Company and its subsidiaries, and Deloitte & Touche LLP, who have certified certain financial statements of the Company and its subsidiaries, are each an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Company Accounting Oversight Board (United States) and as required by the Securities Act.

(oo) Incorporated Documents. The documents incorporated by reference in the General Disclosure Package and the Final Offering Circular, when they were filed with the Commission, conformed in all material respects to the requirements of the Exchange Act, and none of such documents contained any untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the General Disclosure Package and the Final Offering Circular, when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act and will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(pp) No Unlawful Payments. Neither the Company nor any of its subsidiaries nor, to the knowledge of the Company, any director, officer, agent, employee or other person associated with or acting on behalf of the Company or any of its subsidiaries has (A) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (B) made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; (C) violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977; or (D) made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment.

(qq) Compliance with Money Laundering Laws. The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Money Laundering Laws”) and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(rr) Compliance with OFAC. None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or affiliate of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Department of the Treasury (“OFAC”); and the Company will not, directly or indirectly, use the proceeds of the offering of the Offered Securities hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

(ss) No Restrictions on Subsidiaries. No subsidiary of the Company that is a party to the Credit Agreement, dated June 27, 2008 to which the Company is a party, is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s properties or assets to the Company or any other subsidiary of the Company.

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3. Purchase, Sale and Delivery of Offered Securities. On the basis of the representations, warranties and agreements and subject to the terms and conditions set forth herein, the Company agrees to sell to the several Purchasers, and each of the Purchasers agrees, severally and not jointly, to purchase from the Company, at a purchase price of U.S. $97.00 per share plus accumulated dividends from September 29, 2009 to the First Closing Date (as hereinafter defined), the respective number of shares of Firm Securities set forth opposite the names of the several Purchasers in Schedule A hereto.

The Company will deliver the Firm Securities to or as instructed by the Representatives for the accounts of the several Purchasers in a form reasonably acceptable to the Representatives against payment of the purchase price by the Purchasers in Federal (same day) funds by wire transfer to an account at a bank acceptable to the Representatives drawn to the order of the Company at the office of Cahill Gordon & Reindell LLP, at 10 a.m., New York City time, on September 29, 2009 or at such other time not later than seven full business days thereafter as the Representatives and the Company determine, such time being herein referred to as the “First Closing Date”. The Offered Securities so to be delivered or evidence of their issuance will be made available for checking at the above office of Cahill Gordon & Reindell LLP at least 24 hours prior to the First Closing Date.

In addition, upon written notice from the Representatives given to the Company from time to time not more than 30 days subsequent to the date of this Agreement, the Purchasers may purchase all or less than all of the Optional Securities at the purchase price per Offered Security (including any accumulated dividends thereon to the related Optional Closing Date) to be paid for the Firm Securities. The Company agrees to sell to the Purchasers the number of Optional Securities specified in such notice and the Purchasers agree, severally and not jointly, to purchase such Optional Securities. Such Optional Securities shall be purchased from the Company for the account of each Purchaser in the same proportion as the number of Firm Securities set forth opposite such Purchaser’s name in Schedule A hereto bears to the total number of Firm Securities (subject to adjustment by the Representatives to eliminate fractions). No Optional Securities shall be sold or delivered unless the Firm Securities previously have been, or simultaneously are, sold and delivered. The right to purchase the Optional Securities or any portion thereof may be exercised from time to time and to the extent not previously exercised may be surrendered and terminated at any time upon notice by the Representatives to the Company.

Each time for the delivery of and payment for the Optional Securities, being herein referred to as the “Optional Closing Date”, which may be the First Closing Date (the First Closing Date and each Optional Closing Date, if any, being sometimes referred to as a “Closing Date”), shall be determined by the Representatives on behalf of the several Purchasers but shall not be later than seven full business days after written notice of election to purchase Optional Securities is given. Payment for the Optional Securities being purchased on each Optional Closing Date shall be made by the Purchasers in United States dollars in Federal (same day) funds by wire transfer to an account at a bank acceptable to the Representatives drawn to the order of the Company at 10:00 a.m. (New York City time) on the Optional Closing Date against delivery to or as instructed by the Representatives for the account of the several Purchasers of the Optional Securities in a form reasonably acceptable to the Representatives. The Optional Securities being purchased on each Optional Closing Date or evidence of their issuance will be made available for checking at the above offices of Cahill Gordon & Reindell LLP at a reasonable time in advance of such Optional Closing Date.

4. Representations by Purchasers; Resale by Purchasers. (a) Each Purchaser severally represents and warrants to the Company that it is an “accredited investor” within the meaning of Regulation D under the Securities Act.

(b) Each Purchaser severally acknowledges that the Offered Securities have not been registered under the Securities Act and may not be offered or sold within the United States or to, or for the account or benefit of, U.S. persons except in accordance with Regulation S or pursuant to an exemption from the registration requirements of the Securities Act. Each Purchaser

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severally represents and agrees that it has offered and sold the Offered Securities, and will offer and sell the Offered Securities, only in accordance with Rule 903 or Rule 144A. Accordingly, neither such Purchaser nor its affiliates, nor any persons acting on its or their behalf, have engaged or will engage in any directed selling efforts with respect to the Offered Securities, and such Purchaser, its affiliates and all persons acting on its or their behalf have complied and will comply with the offering restrictions requirement of Regulation S and Rule 144A.

(c) Each Purchaser agrees that it and each of its affiliates has not entered and will not enter into any contractual arrangement with respect to the distribution of the Offered Securities except with the prior written consent of the Company.

(d) Each Purchaser agrees that it and each of its affiliates will not offer or sell the Offered Securities in the United States by means of any form of general solicitation or general advertising within the meaning of Rule 502(c), including, but not limited to (i) any advertisement, article, notice or other communication published in any newspaper, magazine or similar media or broadcast over television or radio, or (ii) any seminar or meeting whose attendees have been invited by any general solicitation or general advertising. Each Purchaser agrees, with respect to resales made in reliance on Rule 144A of any of the Offered Securities, to deliver either with the confirmation of such resale or otherwise prior to settlement of such resale a notice to the effect that the resale of such Offered Securities has been made in reliance upon the exemption from the registration requirements of the Securities Act provided by Rule 144A.

(e) Each Purchaser acknowledges and agrees that the Company and, for the purpose of the opinions to be delivered to the Purchasers pursuant to Sections 7(d) and (e), counsel for the Company and counsel for the Purchasers, respectively, may rely on the accuracy of the representations and warranties of the Purchasers, and compliance by the Purchasers with their agreements contained in paragraph (d) above, and each Purchaser hereby consents to such reliance.

5. Certain Agreements of the Company. The Company agrees with the several Purchasers that:

(a) Amendments and Supplements to Offering Circulars. The Company will promptly advise the Representatives of any proposal to amend or supplement the Preliminary or Final Offering Circular and will not effect such amendment or supplementation without the Representatives’ consent. If, at any time prior to the completion of the resale of the Offered Securities by the Purchasers, there occurs an event or development as a result of which any document included in the Preliminary or Final Offering Circular, the General Disclosure Package or any Supplemental Marketing Material, if republished immediately following such event or development, included or would include an untrue statement of a material fact or omitted or would omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it is necessary at any such time to amend or supplement the Preliminary or Final Offering Circular, the General Disclosure Package or any Supplemental Marketing Material to comply with any applicable law, the Company promptly will notify the Representatives of such event and promptly will prepare and furnish, at its own expense, to the Purchasers and to any other dealers at the request of the Representatives, an amendment or supplement which will correct such statement or omission. Neither the Representatives’ consent to, nor their delivery to offerees or investors of, any such amendment or supplement shall constitute a waiver of any of the conditions set forth in Section 7.

(b) Furnishing of Offering Circulars. The Company will furnish to the Representatives copies of the Preliminary Offering Circular, each other document comprising a part of the General Disclosure Package, the Final Offering Circular, all amendments and supplements to such documents and each item of Supplemental Marketing Material, in each case as soon as available and in such quantities as the Representatives request, and the Company will furnish to the Representatives on the date hereof three copies of each of the foregoing documents signed by a duly authorized officer of the Company, one of which in the case of the Preliminary Offering

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Circular and the Final Offering Circular will include the independent accountants’ reports manually signed by such independent accountants. At any time when the Company is not subject to Section 13 or 15(d) of the Exchange Act, the Company will promptly furnish or cause to be furnished to the Purchasers and, upon request of holders and prospective purchasers of the Offered Securities, to such holders and purchasers, copies of the information required to be delivered to holders and prospective purchasers of the Offered Securities pursuant to Rule 144A(d)(4) (or any successor provision thereto) in order to permit compliance with Rule 144A in connection with resales by such holders of the Offered Securities. The Company will pay the expenses of printing and distributing to the Purchasers all such documents.

(c) Blue Sky Qualifications. The Company will arrange for the qualification of the Offered Securities and the Underlying Shares for sale and the determination of their eligibility for investment under the laws of such jurisdictions in the United States and Canada as the Representatives designate and will continue such qualifications in effect so long as required for the resale of the Offered Securities by the Purchasers, provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(d) Reporting Requirements. For so long as the Offered Securities remain outstanding, the Company will furnish to each Purchaser as soon as practicable after the end of each fiscal year, a copy of its annual report to shareholders for such year; and the Company will furnish to such Purchaser (i) as soon as available, a copy of each report and any definitive proxy statement of the Company filed with the Commission under the Exchange Act or mailed to shareholders, and (ii) from time to time, such other information concerning the Company as such Purchaser may reasonably request. However, so long as the Company is subject to the reporting requirements of either Section 13 or Section 15(d) of the Exchange Act and is timely filing reports with the Commission on its Electronic Data Gathering, Analysis and Retrieval system (“EDGAR”), it is not required to furnish such reports or statements to the Purchaser.

(e) Transfer Restrictions. During the period of one year after the later of the First Closing Date and the last Optional Closing Date, the Company will, upon request, furnish to each Purchaser and any holder of Offered Securities a copy of the restrictions on transfer applicable to the Offered Securities.

(f) No Resales by Affiliates. During the period of one year after the later of the First Closing Date and the last Optional Closing Date, the Company will not, and will not permit any of its affiliates (as defined in Rule 144) to, resell any of the Offered Securities that have been reacquired by any of them.

(g) Investment Company. During the period of two years after the later of the First Closing Date and the last Optional Closing Date, the Company will not be, or become, an open-end investment company, unit investment trust or face-amount certificate company that is or is required to be registered under Section 8 of the Investment Company Act.

(h) Payment of Expenses. The Company will pay all expenses incidental to the performance of its obligations under this Agreement, including but not limited to (i) all expenses in connection with the execution, issue, authentication, packaging and initial delivery of the Offered Securities, the preparation and printing of this Agreement, the Offered Securities, the Preliminary Offering Circular, any other documents comprising any part of the General Disclosure Package, the Final Offering Circular, all amendments and supplements thereto, each item of Supplemental Marketing Material and any other document relating to the issuance, offer, sale and delivery of the Offered Securities; (ii) the cost of any advertising approved by the Company in connection with the issue of the Offered Securities; (iii) any expenses (including fees and disbursements of counsel to the Purchasers) incurred in connection with qualification of the

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Offered Securities for sale under the laws of such jurisdictions in the United States and Canada as the Purchasers designate and the preparation and printing of memoranda relating thereto, (iv) any fees charged by investment rating agencies for the rating of the Offered Securities, and (v) expenses incurred in distributing the Preliminary Offering Circular, any other documents comprising any part of the General Disclosure Package, the Final Offering Circular (including any amendments and supplements thereto) and any Supplemental Marketing Material to the Purchasers. The Company will also pay or reimburse the Purchasers (to the extent incurred by them) for costs and expenses of the Purchasers and the Company’s officers and employees and any other expenses of the Purchasers and the Company relating to investor presentations on any “road show” in connection with the offering and sale of the Offered Securities including, without limitation, any travel expenses of the Company’s officers and employees and any other expenses of the Company including the chartering of airplanes.

(i) Use of Proceeds. The Company will use the net proceeds received in connection with this offering in the manner described in the “Use of Proceeds” section of the General Disclosure Package and the Final Offering Circular and, except as disclosed in the General Disclosure Package and the Final Offering Circular, the Company does not intend to use any of the proceeds from the sale of the Offered Securities hereunder to repay any outstanding debt owed to any affiliate of any Purchaser.

(j) Absence of Manipulation. In connection with the offering, until the Representatives shall have notified the Company and the other Purchasers of the completion of the resale of the Offered Securities, neither the Company nor any of its affiliates will, either alone or with one or more other persons, bid for or purchase for any account in which it or any of its affiliates has a beneficial interest any Offered Securities or attempt to induce any person to purchase any Offered Securities; and neither it nor any of its affiliates will make bids or purchases for the purpose of creating actual, or apparent, active trading in, or of raising the price of, the Offered Securities.

(k) Restriction on Sale of Securities. For a period of 90 days after the date of the Final Offering Circular, the Company will not (i) offer, pledge, announce the intention to sell, 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 or otherwise transfer or dispose of, directly or indirectly, the Offered Securities, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (other than the concurrent offering of shares as described in the General Disclosure Package and the Final Offering Circular) or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Offered Securities or the Common Stock, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, without the prior written consent of the Representatives, other than the Offered Securities to be sold hereunder and any shares of Common Stock of the Company issued upon the exercise of options granted under stock option plans described in the General Disclosure Package and the Final Offering Circular. Notwithstanding the foregoing, if (1) during the last 17 days of the 90-day restricted period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (2) prior to the expiration of the 90-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 90-day period, the restrictions imposed by this Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event.

6. Free Writing Communications. (a) Issuer Free Writing Communications. The Company represents and agrees that, unless it obtains the prior consent of the Representatives, it has not made and will not make any offer relating to the Offered Securities that would constitute an Issuer Free Writing Communication.

(b) Term Sheets. The Company consents to the use by any Purchaser of a Free Writing Communication that (i) contains only (A) information describing the preliminary terms of the

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Offered Securities or their offering or (B) information that describes the final terms of the Offered Securities or their offering and that is included in or is subsequently included in the Final Offering Circular or (ii) does not contain any material information about the Company or its securities that was provided by or on behalf of the Company, it being understood and agreed that the Company shall not be responsible to any Purchaser for liability arising from any inaccuracy in such Free Writing Communications referred to in clause (i) or (ii) as compared with the information in the Preliminary Offering Circular, the Final Offering Circular or the General Disclosure Package.

7. Conditions of the Obligations of the Purchaser. The obligations of the several Purchasers to purchase and pay for the Firm Securities on the First Closing Date and for the Optional Securities on each Optional Closing Date will be subject to the accuracy of the representations and warranties of the Company herein (as though made on such Closing Date), to the accuracy of the statements of officers of the Company made pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions precedent:

(a) Accountants’ Comfort Letter. The Purchasers shall have received letters (A) on the date hereof, from PricewaterhouseCoopers LLP and Deloitte & Touche LLP, dated the date hereof, and (B) on each Closing Date, from PricewaterhouseCoopers LLP, dated as of such Closing date, confirming that they are a registered public accounting firm and independent public accountants within the meaning of the Securities Laws and substantially in the form of Schedule D hereto (except that, in any letter dated a Closing Date, the specified date referred to in Schedule D hereto shall be of a date no more than three days prior to such Closing Date).

(b) Reserve Engineers’ Letters. The Purchasers shall have received a letter dated the date hereof and such Closing Date, of each of Ryder Scott Company, L.P. and Collarini Associates (i) confirming that as of the date of its Reserve Reports, it was an independent reserve engineer for the Company and/or its subsidiaries and that as of the date of such letter no information has come to its attention that could reasonably be expected to cause it to withdraw its Reserve Report and (ii) otherwise in form and substance acceptable to the Purchasers.

(c) No Material Adverse Change. Subsequent to the execution and delivery of this Agreement, there shall not have occurred (i) any change, or any development or event involving a prospective change, in the condition (financial or otherwise), results of operations, business, properties or prospects of the Company and its subsidiaries taken as a whole which, in the judgment of the Representatives, is material and adverse and makes it impractical or inadvisable to market the Offered Securities; (ii) any downgrading in the rating of any debt securities or preferred stock of the Company by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g)), or any public announcement that any such organization has under surveillance or review its rating of any debt securities or preferred stock of the Company (other than an announcement with positive implications of a possible upgrading, and no implication of a possible downgrading, of such rating); (iii) any change in U.S. or international financial, political or economic conditions or currency exchange rates or exchange controls the effect of which is such as to make it, in the judgment of the Representatives, impractical to market or to enforce contracts for the sale of the Offered Securities, whether in the primary market or in respect of dealings in the secondary market, (iv) any suspension or material limitation of trading in securities generally on the New York Stock Exchange or the Nasdaq Global Select Market, or any setting of minimum or maximum prices for trading on such exchange; (v) any suspension of trading of any securities of the Company on any exchange or in the over-the-counter market; (vi) any banking moratorium declared by any U.S. Federal or New York authorities; (vii) any major disruption of settlements of securities, payment, or clearance services in the United States or any other country where such securities are listed or (viii) any attack on, outbreak or escalation of hostilities or act of terrorism involving the United States, any declaration of war by Congress or any other national or international calamity or emergency if, in the judgment of the Representatives, the effect of any such attack, outbreak, escalation, act, declaration, calamity or emergency is such as to make it in the judgment of the Representatives impractical or inadvisable to market the Offered Securities or to enforce contracts for the sale of the Offered Securities.

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(d) Opinion of Counsel for Company. The Purchasers shall have received an opinion, dated such Closing Date, of Jackson Walker L.L.P., counsel for the Company that:

(i) Good Standing of the Company. The Company has been duly incorporated and is existing and in good standing under the laws of the State of Texas, with corporate power and authority to own its properties and conduct its business as described in the General Disclosure Package, the Final Offering Circular and Exchange Act Reports;

(ii) Offered Securities. The Offered Securities delivered on such Closing Date have been duly authorized and validly issued, are fully paid and nonassessable and conform to the description thereof contained in the General Disclosure Package and the Final Offering Circular; and the shareholders of the Company have no statutory preemptive rights with respect to the Offered Securities;

(iii) Underlying Shares. The Offered Securities delivered on such Closing Date are convertible into Common Stock of the Company in accordance with their terms; the shares of such Common Stock initially issuable upon conversion of the Offered Securities delivered on such Closing Date have been duly authorized and reserved for issuance upon such conversion and conform to the description of such Common Stock contained in the General Disclosure Package and the Final Offering Circular; the shareholders of the Company have no statutory preemptive rights with respect to the issuance of the Underlying Shares upon the conversion of the Offered Securities in any case pursuant to the Company’s Amended and Restated Articles of Incorporation, the Amended and Restated Bylaws, as amended, the Texas Business Corporation Act; and all Underlying Shares, when issued upon conversion of the Offered Securities, will be validly issued, fully paid and nonassessable;

(iv) Investment Company. The Company is not and, after giving effect to the offering and sale of the Offered Securities and the application of the proceeds thereof as described in the General Disclosure Package, will not be an “investment company” as defined in the Investment Company Act;

(v) Absence of Further Requirements. No consent, approval, authorization, order, license, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance of this Agreement and the consummation of the transactions contemplated by this Agreement in connection with the offering, issuance and sale of the Offered Securities and Underlying Shares by the Company, except such as have been or will be obtained prior to the consummation of the offering;

(vi) Litigation. Based solely on counsel’s review of the information set forth in the certificates of officers of the Company delivered to counsel in connection with such opinion, which review is approved by Purchasers, counsel has no knowledge of any material actions, suits, proceedings or investigations pending or threatened against or affecting the Company or its property in any court or before any governmental agency;

(vii) Absence of Defaults and Conflicts Resulting from Transaction. The execution, delivery and performance of this Agreement and the issuance and sale of the Offered Securities and the Underlying Shares and the consummation of the transactions contemplated by this Agreement will not (a) breach, conflict with or violate, or necessitate any filing or registration under (i) any Texas or Federal law, (ii) any order, writ, judgment, injunction, decree, determination or award known to counsel for the Company to be applicable to the Company or any property of the Company or (iii) any provisions of the Restated Articles of Incorporation or the Amended and Restated Bylaws of the Company, or (b) breach or conflict with any indenture, instrument or other agreement filed as an exhibit to the Company’s Annual Report on Form 10-K for the year ended December 31, 2008;

17

(viii) Disclosure. No information has come to such counsel’s attention that leads it to believe that the Final Offering Circular as of its date and as of such Closing Date, contained any untrue statement of a material fact or omitted to state any material fact necessary to make the statements therein not misleading; such counsel have no reason to believe that the General Disclosure Package, as of the Applicable Time and as of such Closing Date, contained any untrue statement of a material fact necessary to make the statements therein not misleading; it being understood that such counsel need express no opinion as to the financial statements, other financial data, representations and warranties and other statements of fact included in the exhibits to the Exchange Act Reports incorporated by reference to the Final Offering Circular or oil and natural gas reserve information contained in the General Disclosure Package, the Final Offering Circular and the Exchange Act Reports;

(ix) Authorization of Agreement. This Agreement has been duly authorized, executed and delivered by the Company;

(x) Accurate Disclosure. The statements in the General Disclosure Package and the Final Offering Circular under the headings “Certain U.S. Federal Income Tax Considerations”, “Description of Convertible Preferred Stock”, and “Description of Capital Stock” insofar as such statements purport to summarize certain provisions of the documents and legal matters referred to therein, fairly summarize such provisions and legal matters in all material respects, subject to the qualifications and assumptions stated therein; and

(xi) No Registration. Assuming (i) the accuracy of the representations and warranties of the Company set forth in Section 1 hereof, (ii) the due performance by the Company and the Purchasers of the covenants and agreements set forth in this Agreement, (iii) the compliance by the Purchasers with the offering and transfer procedures and the restrictions described in the Final Offering Circular, (iv) the accuracy of the representations and warranties of the Purchasers set forth in Section 4 hereof, (v) the accuracy of the representations and warranties made or deemed to be made in accordance with this Agreement and the Final Offering Circular by purchasers to whom the Purchasers initially resell the Offered Securities, and (vi) that purchasers to whom the Purchasers initially resell the Offered Securities have been made aware of the information set forth in the Final Offering Circular under the caption “Transfer Restrictions”, (A) the offer, issue, sale and delivery of the Offered Securities to the Purchasers and the initial resale of the Offered Securities by the Purchasers, each in the manner contemplated by this Agreement and the Final Offering Circular, and (B) the issuance of Underlying Shares to holders of the Offered Securities upon conversion thereof in accordance with the terms of the Statement of Resolutions, do not require registration under the Securities Act; provided, however, that such counsel need express no opinion as to any subsequent resale or other transfer of any Offered Securities or any Underlying Shares.

(e) Opinions of Counsel for Purchasers. The Purchasers shall have received from each of Cahill Gordon & Reindel LLP and Cravath, Swaine & Moore LLP, counsel for the Purchasers, such opinion or opinions, dated such Closing Date, with respect to such matters as the Purchasers may require, and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

(f) Officers’ Certificate. The Purchasers shall have received a certificate, dated such Closing Date, of an executive officer of the Company and a principal financial or accounting officer of the Company in which such officers shall state that the representations and warranties of the Company in this Agreement are true and correct, that the Company has complied with all

18

agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to such Closing Date, and that, subsequent to the respective dates of the most recent financial statements in the General Disclosure Package and Exchange Act Reports and there has been no material adverse change, nor any development or event involving a prospective material adverse change, in the condition (financial or otherwise), results of operations, business, properties or prospects of the Company and its subsidiaries taken as a whole except as set forth in the General Disclosure Package and Exchange Act Reports or as described in such certificate.

(g) Lockup Letters. On or prior to the date hereof, the Purchasers shall have received lockup letters from each of the directors of the Company and each of the executive officers of the Company that is a reporting person under Section 16 of the Exchange Act.

(h) No Downgrade. Subsequent to the earlier of (A) the Applicable Time and (B) the execution and delivery of this Agreement, if there are any debt securities or preferred stock of, or guaranteed by, the Company or any of its subsidiaries that are rated by a “nationally recognized statistical rating organization,” as such term is defined by the Commission for purposes of Rule 436(g)(2) under the Securities Act, (i) no downgrading shall have occurred in the rating accorded any such debt securities or preferred stock and (ii) no such organization shall have publicly announced that it has under surveillance or review, or has changed its outlook with respect to, its rating of any such debt securities or preferred stock (other than an announcement with positive implications of a possible upgrading).

(i) Chief Financial Officer’s Certificate. The Purchasers shall have received on and as of such Closing Date a certificate of the Chief Financial Officer of the Company to the effect that as of such Closing Date in the form and substance reasonably satisfactory to the Representatives, to the effect set forth in Exhibit A hereto.

(j) No Legal Impediment to Issuance. No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would as of such Closing Date prevent the issuance or sale of the Offered Securities; and no injunction or order of any federal, state or foreign court shall have been issued that would as of such Closing Date prevent the issuance or sale of the Offered Securities.

(k) Good Standing. The Representatives shall have received on and as of such Closing Date satisfactory evidence of the good standing of the Company in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

Documents described as being “in the agreed form” are documents which are in the forms which have been initialed for the purpose of identification by Cahill Gordon & Reindell LLP and Cravath, Swaine & Moore LLP, copies of which are held by the Company and the Representatives, with such changes as the Representatives may approve.

The Company will furnish the Purchasers with such conformed copies of such opinions, certificates, letters and documents as the Purchasers reasonably request. The Representatives may in their sole discretion waive on behalf of the Purchasers compliance with any conditions to the obligations of the Purchasers hereunder, whether in respect of an Optional Closing Date or otherwise.

8. Indemnification and Contribution. (a) Indemnification of Purchasers. The Company will indemnify and hold harmless each Purchaser, its officers, employees, agents, partners, members, directors and its affiliates and each person, if any, who controls such Purchaser within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act (each, an “Indemnified Party”), against any and all losses, claims, damages or liabilities, joint or several, to which such Indemnified Party may become subject, under the Securities Act, the Exchange Act, other Federal or state statutory law or regulation or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or

19

are based upon any untrue statement or alleged untrue statement of any material fact contained in the Preliminary Offering Circular or the Final Offering Circular, in each case as amended or supplemented, or any Issuer Free Writing Communication (including, without limitation, any Supplemental Marketing Material) or the Exchange Act Reports, or arise out of or are based upon the omission or alleged omission of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading and will reimburse each Indemnified Party for any legal or other expenses reasonably incurred by such Indemnified Party in connection with investigating, preparing or defending against any loss, claim, damage, liability, action, litigation, investigation or proceeding whatsoever (whether or not such Indemnified Party is a party thereto) whether threatened or commenced and in connection with the enforcement of this provision with respect to any of the above as such expenses are incurred; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement in or omission or alleged omission from any of such documents in reliance upon and in conformity with written information furnished to the Company by any Purchaser through the Representatives specifically for use therein, it being understood and agreed that the only such information consists of the information described as such in subsection (b) below.

(b) Indemnification of Company. Each Purchaser will severally and not jointly indemnify and hold harmless the Company, each of its directors and officers and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act (each, a “Purchaser Indemnified Party”), against any losses, claims, damages or liabilities to which such Purchaser Indemnified Party may become subject, under the Securities Act, the Exchange Act, other Federal or state statutory law or regulation or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of any material fact contained in the Preliminary Offering Circular or the Final Offering Circular, in each case as amended or supplemented, or any Issuer Free Writing Communication or arise out of or are based upon the omission or the alleged omission of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company by such Purchaser through the Representatives specifically for use therein, and will reimburse any legal or other expenses reasonably incurred by such Purchaser Indemnified Party in connection with investigating, preparing or defending against any such loss, claim, damage, liability, action, litigation, investigation or proceeding whatsoever (whether or not such Purchaser Indemnified Party is a party thereto) whether threatened or commenced based upon any such untrue statement or omission, or any such alleged untrue statement or omission as such expenses are incurred, it being understood and agreed that the only such information furnished by any Purchaser consists of the following information in the Preliminary and Final Offering Circular: under the caption “Plan of Distribution” the first sentence of paragraph three, the second sentence of paragraph nine and paragraph ten; provided, however, that the Purchaser shall not be liable for any losses, claims, damages or liabilities arising out of or based upon the Company’s failure to perform its obligations under Section 5(a) of this Agreement.

(c) Actions against Parties; Notification. Promptly after receipt by an indemnified party under this Section of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made against the indemnifying party under subsection (a) or (b) above, notify the indemnifying party of the commencement thereof; provided that the failure to notify the indemnifying party shall not relieve it from any liability that it may have under subsection (a) or (b) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided further that the failure to notify the indemnifying party shall not relieve it from any liability that it may have to an indemnified party otherwise than under subsection (a) or (b) above. In case any such action is brought against any indemnified party and it notifies the indemnifying party of the commencement thereof, the indemnifying party will be entitled to participate therein and, to the extent that it may wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party (who shall not, except with the consent of the indemnified party, be counsel to the indemnifying party), and after notice from the indemnifying party to such indemnified party of its election so to assume the defense thereof, the indemnifying party will not be

20

liable to such indemnified party under this Section for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof other than reasonable costs of investigation. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened action in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party unless such settlement includes (i) an unconditional release of such indemnified party from all liability on any claims that are the subject matter of such action and (ii) does not include a statement as to or an admission of fault, culpability or failure to act by or on behalf of any indemnified party.

(d) Contribution. If the indemnification provided for in this Section is unavailable or insufficient to hold harmless an indemnified party under subsection (a) or (b) above, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of the losses, claims, damages or liabilities referred to in subsection (a) or (b) above (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Purchasers on the other from the offering of the Offered Securities or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company on the one hand and the Purchasers on the other in connection with the statements or omissions which resulted in such losses, claims, damages or liabilities as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Purchasers on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company bear to the total discounts and commissions received by the Purchasers from the Company under this Agreement. The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or the Purchasers and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The amount paid by an indemnified party as a result of the losses, claims, damages or liabilities referred to in the first sentence of this subsection (d) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any action or claim which is the subject of this subsection (d). Notwithstanding the provisions of this subsection (d), no Purchaser shall be required to contribute any amount in excess of the amount by which the total price at which the Offered Securities purchased by it were resold exceeds the amount of any damages which such Purchaser has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. The Company and the Purchasers agree that it would not be just and equitable if contribution pursuant to this Section 8(d) were determined by pro rata allocation (even if the Purchasers were treated as one entity for such purpose) or by any other method of allocation which does not take account of the equitable considerations referred to in this Section 8(d).

9. Default of Purchasers. If any Purchaser or Purchasers default in their obligations to purchase Offered Securities hereunder on either the First Closing Date or any Optional Closing Date and the aggregate number of Offered Securities that such defaulting Purchaser or Purchasers agreed but failed to purchase does not exceed 10% of the total number of Offered Securities that the Purchasers are obligated to purchase on such Closing Date, the Representatives may make arrangements satisfactory to the Company for the purchase of such Offered Securities by other persons, including any of the Purchasers, but if no such arrangements are made by such Closing Date, the non-defaulting Purchasers shall be obligated severally, in proportion to their respective commitments hereunder, to purchase the Offered Securities that such defaulting Purchasers agreed but failed to purchase on such Closing Date. If any Purchaser or Purchasers so default and the aggregate number of Offered Securities with respect to which such default or defaults occur exceeds 10% of the total number of shares of Offered Securities that the Purchasers are obligated to purchase on such Closing Date and arrangements satisfactory to the Representatives and the Company for the purchase of such Offered Securities by other persons are not made within 36 hours after such default, this Agreement will terminate without liability on the part of any non-defaulting Purchaser or the Company, except as provided in Section 10 (provided that if such default occurs with respect to Optional Securities after the First Closing Date, this Agreement shall not terminate as to the Firm Securities or any Optional Securities purchased prior to such termination). As used in this Agreement, the term “Purchaser” includes any person substituted for a Purchaser under this Section. Nothing herein will relieve a defaulting Purchaser from liability for its default.

21

10. Survival of Certain Representations and Obligations. The respective indemnities, agreements, representations, warranties and other statements of the Company or its officers and of the several Purchasers set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation, or statement as to the results thereof, made by or on behalf of any Purchaser, the Company or any of their respective representatives, officers or directors or any controlling person, and will survive delivery of and payment for the Offered Securities. If this Agreement is terminated pursuant to Section 9 or if for any reason the purchase of the Offered Securities by the Purchasers is not consummated, the Company shall remain responsible for the expenses to be paid or reimbursed by it pursuant to Section 5 and the respective obligations of the Company and the Purchasers pursuant to Section 8 shall remain in effect and if any Offered Securities have been purchased hereunder the representations and warranties in Section 2 and all obligations under Section 5 shall also remain in effect. If the purchase of the Offered Securities by the Purchasers is not consummated for any reason other than solely because of the termination of this Agreement pursuant to Section 9 or the occurrence of any event specified in clause (iii), (iv), (vi), (vii) or (viii) of Section 7(c), the Company will reimburse the Purchasers for all out-of-pocket expenses (including fees and disbursements of counsel) reasonably incurred by it in connection with the offering of the Offered Securities.

11. Notices. All communications hereunder will be in writing and, if sent to the Purchasers will be mailed, delivered or telegraphed and confirmed to the Purchasers at Credit Suisse Securities (USA) LLC, Eleven Madison Avenue, New York, NY 10010-3629, Attention: LCD-IBD, and J.P.Morgan Securities Inc. 383 Madison Avenue, New York, NY 10179 or, if sent to the Company, will be mailed, delivered or telegraphed and confirmed to it at 4600 Post Oak Place, Suite 200, Houston, Texas 77027, Attention: John Tschirhart, with a copy to Jackson Walker L.L.P., 1401 McKinney St., Suite 1900, Houston, Texas 77010, Attention: Richard Roth.

12. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the controlling persons referred to in Section 8, and no other person will have any right or obligation hereunder, except that holders of Offered Securities shall be entitled to enforce the agreements for their benefit contained in the second and third sentences of Section 5(b) hereof against the Company as if such holders were parties thereto.

13. Counterparts. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same Agreement.

14. Absence of Fiduciary Relationship. The Company acknowledges and agrees that:

(a) No Other Relationship. The Purchasers have been retained solely to act as initial purchasers in connection with the initial purchase, offering and resale of the Offered Securities and that no fiduciary, advisory or agency relationship between the Company and any of the Purchasers has been created in respect of any of the transactions contemplated by this Agreement or the Preliminary or Final Offering Circular, irrespective of whether any Purchaser has advised or is advising the Company on other matters;

(b) Arm’s-Length Negotiations. The purchase price of the Offered Securities set forth in this Agreement was established by the Company following discussions and arms-length negotiations with the Purchasers and the Company is capable of evaluating and understanding and understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement;

(c) Absence of Obligation to Disclose. The Company has been advised that each of the Purchasers and its affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company and that none of the Purchasers has any obligation to disclose such interests and transactions to Company by virtue of any fiduciary, advisory or agency relationship; and

22

(d) Waiver. The Company waives, to the fullest extent permitted by law, any claims it may have against each of the Purchasers for breach of fiduciary duty or alleged breach of fiduciary duty and agrees that none of the Purchasers shall have any liability (whether direct or indirect) to the Company in respect of such a fiduciary duty claim or to any person asserting a fiduciary duty claim on behalf of or in right of the Company, including shareholders, employees or creditors of the Company.

15. Applicable Law. This Agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

The Company hereby submits to the non-exclusive jurisdiction of the Federal and state courts in the Borough of Manhattan in The City of New York in any suit or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby. The Company irrevocably and unconditionally waives any objection to the laying of venue of any suit or proceeding arising out of or relating to this Agreement or the transactions contemplated hereby in Federal and state courts in the Borough of Manhattan in The City of New York and irrevocably and unconditionally waives and agrees not to plead or claim in any such court that any such suit or proceeding in any such court has been brought in an inconvenient forum.

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If the foregoing is in accordance with the Purchasers’ understanding of our agreement, kindly sign and return to us one of the counterparts hereof, whereupon it will become a binding agreement between the Company and the several Purchasers in accordance with its terms.

Very truly yours,
ATP Oil & Gas Corporation
By:	/s/ Leland E. Tate
Name:	Leland E. Tate
Title:	President

The foregoing Purchase Agreement is hereby confirmed and accepted as of the date first above written.
CREDIT SUISSE SECURITIES (USA) LLC
For itself and on behalf of the several Underwriters listed in Schedule 1 hereto.
By:	/s/ Timothy E. Perry
	Authorized Signatory Managing Director
J.P. MORGAN SECURITIES INC.
For itself and on behalf of the several Underwriters listed in Schedule 1 hereto.
By:	/s/ Michael O’Donovan
	Authorized Signatory
	Managing Director
CANACCORD ADAMS INC.
By:	/s/ Christian B. Gibson
	Authorized Signatory
PRITCHARD CAPITAL PARTNERS, LLC.
By:	/s/ Todd Giustiniano
	Authorized Signatory
SMH CAPITAL, INC.
By:	/s/ William W. Sprague
	Authorized Signatory

SCHEDULE A

Purchaser	Shares of Firm Securities	Shares of Optional Securities
Credit Suisse Securities (USA) LLC	531,250	148,750
J.P.Morgan Securities Inc.	531,250	148,750
Canaccord Adams Inc.	62,500	17,500
Pritchard Capital Partners, LLC	62,500	17,500
SMH Capital, Inc.	62,500	17,500
Total	1,250,000	350,000

A-1

SCHEDULE B

1. Issuer Free Writing Communications (included in the General Disclosure Package)

Final term sheet, dated September 23, 2009, a copy of which is attached hereto.

2. Other Information Included in the General Disclosure Package

The following information is also included in the General Disclosure Package:

None.

B-1

SCHEDULE C

Supplemental Marketing Materials

None.

C-1

SCHEDULE D

The Purchaser shall have received letters (A) on the date hereof, from PricewaterhouseCoopers LLP and Deloitte & Touche LLP, dated the date hereof, and (B) on each Closing Date, from PricewaterhouseCoopers LLP, dated as of such Closing date, in each case confirming that they are a registered public accounting firm and independent public accountants within the meaning of the Securities Laws to the effect that:

(i) in their opinion the audited consolidated financial statements and schedules examined by them and included in the Preliminary and Final Offering Circular and in the Exchange Act Reports comply as to form in all material respects with the applicable accounting requirements of the Securities Laws;

(ii) with respect to the period(s) covered by the unaudited quarterly consolidated financial statements included in the Preliminary and Final Offering Circular or in the Exchange Act Reports, they have performed the procedures specified by the American Institute of Certified Public Accountants for a review of interim financial information as described in AU 722, Interim Financial Information, on the unaudited quarterly consolidated financial statements (including the noted thereto) of the Company and its consolidated subsidiaries included in the Preliminary and Final Offering Circular or in the Exchange Act Reports, and have made inquiries of certain officials of the Company who have responsibility for financial and accounting matters of the Company and its consolidated subsidiaries as to whether such unaudited quarterly consolidated financial statements comply as to form in all material respects with the applicable accounting requirements of the Securities Act and the related published rules and regulations; they have read the latest unaudited monthly consolidated financial statements (including the notes thereto) and the supplementary summary unaudited financial information of the Company and its consolidated subsidiaries made available by the Company and the minutes of the meetings of the shareholders, Board of Directors and committees of the Board of Directors of the Company; and have made inquiries of certain officials of the Company who have responsibility for financial and accounting matters of the Company and its consolidated subsidiaries as to whether the unaudited monthly financial statements are stated on a basis substantially consistent with that of the audited consolidated financial statements included in the Preliminary and Final Offering Circular and the Exchange Act Reports; and on the basis thereof, nothing came to their attention which caused them to believe that:

(A) the unaudited financial statements included in the Preliminary and Final Offering Circular or in the Exchange Act Reports do not comply as to form in all material respects with the applicable accounting requirements of the Securities Laws, or that any material modifications should be made to the unaudited quarterly consolidated financial statements for them to be in conformity with generally accepted accounting principles;

(B) with respect to the period subsequent to the date of the most recent unaudited quarterly consolidated financial statements included in the Preliminary and Final Offering Circular or in the Exchange Act Reports, at a specified date at the end of the most recent month, there were any increases in the short-term debt or long-term debt of the Company and its consolidated subsidiaries, or any change in the consolidated capital stock of the Company and its consolidated subsidiaries as compared with the amounts shown on the latest balance sheet included in the Exchange Act Reports except for such changes or increases set forth in such letter which the Exchange Act Reports disclose have occurred or may occur;

(iii) With respect to any period as to which officials of the Company have advised that no consolidated financial statements as of any date or for any period subsequent to the specified date referred to in (ii)(B) above are available, they have made inquiries of certain officials of the Company who have responsibility for the financial and accounting matters of the Company and its

D-1

consolidated subsidiaries as to whether, at a specified date not more than three business days prior to the date of such letter, there were any increases in the short-term debt or long-term debt of the Company and its consolidated subsidiaries, or any change in the consolidated capital stock of the Company and its consolidated subsidiaries as compared with the amounts shown on the most recent balance sheet for such entities included in the Exchange Act Reports and, on the basis of such inquiries and the review of the minutes described in paragraph (ii) above, nothing came to their attention which caused them to believe that there was any such change or increase except for such changes or increases set forth in such letter which the Exchange Act Reports disclose have occurred or may occur; and

(iv) they have compared specified dollar amounts (or percentages derived from such dollar amounts) and other financial and statistical information contained in the Preliminary Offering Circular, each other document comprising any part of the General Disclosure Package, the Final Offering Circular and each item of Supplemental Marketing Material (other than any Supplemental Marketing Material that is an electronic road show and the Exchange Act Reports (in each case to the extent that such dollar amounts, percentages and other financial and statistical information are derived from the general accounting records of the Company and its subsidiaries or are derived directly from such records by analysis or computation) with the results obtained from inquiries, a reading of such general accounting records and other procedures specified in such letter and have found such dollar amounts, percentages and other financial and statistical information to be in agreement with such results.

D-2

EXHIBIT A

FORM OF

ATP OIL & GAS CORPORATION

CHIEF FINANCIAL OFFICER’S CERTIFICATE

I, Albert L. Reese Jr., do hereby certify that I am the Chief Financial Officer of ATP Oil & Gas Corporation, a Texas corporation (the “Company”), and, in my capacity as Chief Financial Officer, and based upon an examination of the Company’s financial records and schedules undertaken by myself or members of my staff who are responsible for the Company’s financial and accounting matters, do hereby certify that:

1. I am providing this certificate in connection with the marketing of [    ] shares of the Company’s [    ]% convertible perpetual preferred stock, as described in that certain offering circular, dated September [    ], 2009 (the “Offering Circular”);

2. I am familiar with the accounting, operations and records systems of the Company;

3. I have read the (1) the Offering Circular, (2) the Annual Report on Form 10-K for the year ended December 31, 2008, (3) the Quarterly Report on Form 10-Q for the quarter ended March 31, 2009 and (4) The Quarterly Report on Form 10-Q for the quarter ended June 30, 2009.

4. No consolidated financial statements of the Company as of any date for any period subsequent to [    ] , 2009 are currently available;

5. I have no reason to believe that for the period from [    ] 2009 to [    ] 2009, there were any decreases, as compared with the corresponding period in the preceding year, in consolidated net sales or in the total or per-share amounts of income before extraordinary items or of net income, except in all instances for changes, increases or decreases that the Offering Circular discloses have occurred or may occur;

6. I have supervised the compilation of and reviewed the circled information contained on the attached Exhibit A, which is included or incorporated by reference into the Offering Circular. I have performed the following procedures with respect to the circled information identified on Exhibit A, which were applied as indicated with respect to the capital letters as explained below, and, to my knowledge, such information is correct, complete and accurate in all material respects:

a. Recomputed and/or compared to corresponding amounts appearing in the accounting records of the Company and found the amounts (as adjusted for rounding, where appropriate) to be in agreement.

b. Compared and agreed (as adjusted for rounding, where appropriate), or recalculated and agreed (as adjusted for rounding, where appropriate), to a schedule derived from the Company’s accounting records, and compared the amounts on the schedule to corresponding amounts appearing in the accounting records and found the amounts to be in agreement (as adjusted for rounding, where appropriate) and determined that the amounts on the schedule were arithmetically correct.

c. Proved the arithmetic accuracy of the percentages and ratios (as adjusted for rounding, where applicable) based on data in the above-mentioned accounting records and schedules.

Ex. A-1

In witness whereof this certificate has been executed and delivered by the chief financial officer of the Company on this      day of September, 2009.

Albert L. Reese, Jr.

Chief Financial Officer

Ex. A-2

EX-99.1

Exhibit 99.1

News Release

For Immediate Release on 9/23/09

ATP Oil & Gas Corporation, Houston

Chairman and CEO

T. Paul Bulmahn, 713-622-3311

or

Chief Financial Officer

Albert L. Reese Jr., 713-622-3311

www.atpog.com

ATP Prices Public Offering of Common Stock

HOUSTON – September 23, 2009 – (Business Wire) – ATP Oil & Gas Corporation (NASDAQ: ATPG) today announced that it has priced its public offering of 5.3 million shares of its common stock at a public offering price of $18.50 per share. ATP has granted the underwriters a 30-day option to purchase up to 0.795 million additional shares of common stock to cover any over-allotments.

Closing of the offering is expected to occur on or about September 29, 2009, subject to customary closing conditions. ATP intends to use the net proceeds from the offering to fund capital expenditures, primarily at its Telemark location in the deepwater Gulf of Mexico, to reduce indebtedness and for general corporate purposes.

J.P. Morgan Securities Inc. and Credit Suisse Securities (USA) LLC are joint book-running managers for the common stock offering. A copy of the preliminary prospectus supplement and related base prospectus for the offering may be obtained on the Securities and Exchange Commission (“SEC”) website at http://www.sec.gov. Alternatively, the underwriters will arrange to send you the preliminary prospectus supplement and related base prospectus if you request them by contacting J.P. Morgan Securities Inc. at 4 Chase Metrotech Center, CS Level, Brooklyn, NY 11245, Attn: Chase Distribution and Support Service, Northeast Statement Processing, or by telephone to (718) 242-8002, or by fax at (718) 242-8003. Requests may also be made by contacting Credit Suisse Securities (USA) LLC, Prospectus Department, One Madison Avenue, New York, NY 10010 or by telephone at (800) 221-1037.

This Press Release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state in which such offer, solicitation or sale of these securities would be unlawful prior to registration or qualification under the securities laws of any such state.

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About ATP Oil & Gas Corporation

ATP Oil & Gas is an international offshore oil and gas development and production company with operations in the Gulf of Mexico and the North Sea. The company trades publicly as ATPG on the NASDAQ Global Select Market.

Forward-looking Statements

Certain statements included in this news release are “forward-looking statements” under the Private Securities Litigation Reform Act of 1995. ATP cautions that assumptions, expectations, projections, intentions, or beliefs about future events may, and often do, vary from actual results and the differences can be material. Some of the key factors which could cause actual results to vary from those ATP expects include changes in natural gas and oil prices, the timing of planned capital expenditures, availability of acquisitions, uncertainties in estimating proved reserves and forecasting production results, operational factors affecting the commencement or maintenance of producing wells, the condition of the capital markets generally, as well as ATP’s ability to access them, and uncertainties regarding environmental regulations or litigation and other legal or regulatory developments affecting our business. More information about the risks and uncertainties relating to ATP’s forward-looking statements are found in the Company’s SEC filings.

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EX-99.2

Exhibit 99.2

News Release

For Immediate Release on 9/23/09

ATP Oil & Gas Corporation, Houston

Chairman and CEO

T. Paul Bulmahn, 713-622-3311

or

Chief Financial Officer

Albert L. Reese Jr., 713-622-3311

www.atpog.com

ATP Prices Private Offering of $125 Million 8.00% Convertible Perpetual Preferred Stock

HOUSTON – September 23, 2009 – (Business Wire) – ATP Oil & Gas Corporation (NASDAQ: ATPG) today announced that it has priced a private offering of 1,250,000 shares of a new series of 8.00% convertible perpetual preferred stock for net proceeds of approximately $121 million. Shares are being issued to qualified institutional buyers eligible under Rule 144A. The company has also granted a 30-day option to the initial purchasers to purchase approximately 350,000 additional shares of convertible perpetual preferred stock to cover any over-allotments.

The annual dividend on each share of convertible preferred stock is $8.00 and is payable quarterly, in arrears, on each January 1, April 1, July 1, and October 1, commencing on January 1, 2010, when, as and if declared by the company’s board of directors. No dividends will accrue or accumulate prior to September 29, 2009. The company may, at its option, pay dividends in cash, common stock or any combination thereof. The convertible perpetual preferred stock has a liquidation preference of $100 per share and is convertible, at the holder’s option, initially into 4.5045 shares of company common stock which is equal to an initial conversion price of approximately $22.20 per share. The conversion ratio will be subject to customary adjustments in certain circumstances. No payment or adjustment for accumulated dividends will be made upon conversion. At any time on or after October 1, 2014, the company may, at its option, cause all outstanding shares of the convertible preferred stock to be automatically converted if the closing price of the company’s common stock equals or exceeds certain thresholds.

Closing of the private offering is expected to occur on September 29, 2009 and will be subject to satisfaction of various customary closing conditions.

The convertible preferred stock and any shares of company common stock issuable pursuant to the terms of the convertible preferred stock have not been registered under the Securities Act of 1933 or applicable state securities laws, and may not be offered or sold in the United States absent registration or an applicable exemption from the registration requirements of the Securities Act and applicable state laws. The company plans to offer and issue the preferred stock only to qualified institutional buyers pursuant to Rule 144A under the Securities Act.

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This press release shall not constitute an offer to sell or the solicitation of an offer to buy nor shall there be any sale of these securities in any state in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any state.

About ATP Oil & Gas Corporation

ATP Oil & Gas is an international offshore oil and gas development and production company with operations in the Gulf of Mexico and the North Sea. The company trades publicly as ATPG on the NASDAQ Global Select Market.

Forward-looking Statements

Certain statements included in this news release are “forward-looking statements” under the Private Securities Litigation Reform Act of 1995. ATP cautions that assumptions, expectations, projections, intentions, or beliefs about future events may, and often do, vary from actual results and the differences can be material. Some of the key factors which could cause actual results to vary from those ATP expects include changes in natural gas and oil prices, the timing of planned capital expenditures, availability of acquisitions, uncertainties in estimating proved reserves and forecasting production results, operational factors affecting the commencement or maintenance of producing wells, the condition of the capital markets generally, as well as ATP’s ability to access them, and uncertainties regarding environmental regulations or litigation and other legal or regulatory developments affecting our business. More information about the risks and uncertainties relating to ATP’s forward-looking statements are found in the Company’s SEC filings.

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EX-99.3

Exhibit 99.3

News Release

For Immediate Release on 9/29/09

ATP Oil & Gas Corporation, Houston

Chairman and CEO

T. Paul Bulmahn, 713-622-3311

or

Chief Financial Officer

Albert L. Reese Jr., 713-622-3311

www.atpog.com

ATP Closes Previously Announced Public Offering of Common Stock

HOUSTON – September 29, 2009 – (Business Wire) – ATP Oil & Gas Corporation (NASDAQ: ATPG) today announced that it has closed its previously announced public offering of 5.3 million shares of its common stock at a public offering price of $18.50 per share.

Net proceeds from the offering were approximately $93.4 million after deducting the underwriters’ discount and estimated offering expenses, and will be used to fund capital expenditures, primarily at its Telemark location in the deepwater Gulf of Mexico, to reduce indebtedness and for general corporate purposes.

J.P. Morgan Securities Inc. and Credit Suisse Securities (USA) LLC acted as joint book-running managers for the common stock offering. In addition, co-managers included Canaccord Adams Inc., Pritchard Capital Partners, LLC, SMH Capital, Inc., Howard Weil Incorporated, Johnson Rice & Company L.L.C., Wunderlich Securities, Inc., C.K. Cooper & Company, Inc., Global Hunter Securities, LLC, Natixis Bleichroeder Inc., Rodman & Renshaw, LLC and FIG Partners, LLC. Copies of the final prospectus supplement and related base prospectus may be obtained from the offices of J.P. Morgan Securities Inc. at 4 Chase Metrotech Center, CS Level, Brooklyn, NY 11245, Attn: Chase Distribution and Support Service, Northeast Statement Processing, or by telephone to (718) 242-8002, or by fax at (718) 242-8003. Requests may also be made by contacting Credit Suisse Securities (USA) LLC, Prospectus Department, One Madison Avenue, New York, NY 10010 or by telephone at (800) 221-1037.

About ATP Oil & Gas Corporation

ATP Oil & Gas is an international offshore oil and gas development and production company with operations in the Gulf of Mexico and the North Sea. The company trades publicly as ATPG on the NASDAQ Global Select Market.

Forward-looking Statements

Certain statements included in this news release are “forward-looking statements” under the Private Securities Litigation Reform Act of 1995. ATP cautions that assumptions, expectations, projections, intentions, or beliefs about

ATP Oil & Gas Corporation 4600 Post Oak Place Suite 200 Houston, TX 77027 www.atpog.com

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future events may, and often do, vary from actual results and the differences can be material. Some of the key factors which could cause actual results to vary from those ATP expects include changes in natural gas and oil prices, the timing of planned capital expenditures, availability of acquisitions, uncertainties in estimating proved reserves and forecasting production results, operational factors affecting the commencement or maintenance of producing wells, the condition of the capital markets generally, as well as ATP’s ability to access them, and uncertainties regarding environmental regulations or litigation and other legal or regulatory developments affecting our business. More information about the risks and uncertainties relating to ATP’s forward-looking statements are found in the Company’s SEC filings.

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ATP Oil & Gas Corporation 4600 Post Oak Place Suite 200 Houston, TX 77027 www.atpog.com

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EX-99.4

Exhibit 99.4

News Release

For Immediate Release on 9/29/09

ATP Oil & Gas Corporation, Houston

Chairman and CEO

T. Paul Bulmahn, 713-622-3311

or

Chief Financial Officer

Albert L. Reese Jr., 713-622-3311

www.atpog.com

ATP Closes Private Placement of 8.0% Convertible Perpetual Preferred Stock

HOUSTON – September 29, 2009 – (Business Wire) – ATP Oil & Gas Corporation (NASDAQ: ATPG) today announced that it has closed its previously announced private placement of a new series of 8.0% convertible perpetual preferred stock. Prior to this private placement closing, the initial purchasers exercised their option to purchase 150,000 shares of preferred stock to cover over-allotments. The total amount of preferred stock issued today by the company was 1,400,000 shares, with an aggregate liquidation preference of $140 million.

This press release does not constitute an offer to sell or the solicitation of an offer to buy any securities (including the shares of common stock into which the securities are convertible) and shall not constitute an offer, solicitation or sale in any jurisdiction in which such offer, solicitation or sale is unlawful. The convertible preferred stock and the underlying common stock issuable upon conversion have not been registered under the Securities Act of 1933 or any applicable state securities laws and may not be offered or sold in the United States, absent registration or an applicable exemption from such registration requirements.

About ATP Oil & Gas Corporation

ATP Oil & Gas is an international offshore oil and gas development and production company with operations in the Gulf of Mexico and the North Sea. The company trades publicly as ATPG on the NASDAQ Global Select Market.

Forward-looking Statements

Certain statements included in this news release are “forward-looking statements” under the Private Securities Litigation Reform Act of 1995. ATP cautions that assumptions, expectations, projections, intentions, or beliefs about future events may, and often do, vary from actual results and the differences can be material. Some of the key factors which could cause actual results to vary from those ATP expects include changes in natural gas and oil prices, the timing of planned capital expenditures, availability of acquisitions, uncertainties in estimating proved reserves and forecasting production results, operational factors affecting the commencement or maintenance of producing wells, the condition of the capital markets generally, as well as ATP’s ability to access them, and uncertainties regarding environmental regulations or litigation and other legal or regulatory developments affecting our business. More information about the risks and uncertainties relating to ATP’s forward-looking statements are found in the Company’s SEC filings.

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ATP Oil & Gas Corporation 4600 Post Oak Place Suite 200 Houston, TX 77027 www.atpog.com