10,000,000 Shares

Exhibit 1.1

Execution Version

10,000,000 Shares

Common Stock

UNDERWRITING AGREEMENT

June 4, 2009

Credit Suisse Securities (USA) LLC
J.P. Morgan Securities Inc.
Merrill Lynch, Pierce, Fenner & Smith Incorporated,
As Representatives of the Several Underwriters,
c/o Credit Suisse Securities (USA) LLC,
      Eleven Madison Avenue
      New York, N.Y. 10010-3629

Dear Sirs:

     1. Introductory. Mariner Energy, Inc., a Delaware corporation (“Company”), agrees with the several Underwriters named in Schedule A hereto (“Underwriters”) to issue and sell to the several Underwriters 10,000,000 shares (“Firm Securities”) of its common stock, $0.0001 par value (the “Securities”), and also agrees to issue and sell to the Underwriters, at the option of the Underwriters, an aggregate of not more than 1,500,000 additional shares (“Optional Securities”) of its Securities as set forth below. The Firm Securities and the Optional Securities are herein collectively called the “Offered Securities”.

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

     (a) Filing and Effectiveness of Registration Statement; Certain Defined Terms. The Company has filed with the Commission a registration statement on Form S-3ASR (No. 333-159682), including a related prospectus or prospectuses, covering the registration of the Offered Securities under the Act, which has become effective. “Registration Statement” at any particular time means such registration statement in the form then filed with the Commission, including any amendment thereto, all exhibits thereto (but not including the Statement of Eligibility of Trustee on Form T-1), any document incorporated by reference therein and all 430B Information and all 430C Information with respect to such registration statement, that in any case has not been superseded or modified. “Registration Statement” without reference to a time means the Registration Statement as of the Effective Time. For purposes of this definition, 430B Information shall be considered to be included in the Registration Statement as of the time specified in Rule 430B.

     For purposes of this underwriting agreement (this “Agreement”):

     “430B Information” means information included in a prospectus then deemed to be a part of the Registration Statement pursuant to Rule 430B(e) or retroactively deemed to be a part of the Registration Statement pursuant to Rule 430B(f).

     “430C Information” means information included in a prospectus then deemed to be a part of the Registration Statement pursuant to Rule 430C.

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

     “Applicable Time” means 11:30 pm (Eastern time) on the date of this Agreement.

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

     “Commission” means the Securities and Exchange Commission.

     “Effective Time” of the Registration Statement relating to the Offered Securities means the time of the first contract of sale for the Offered Securities.

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

     “Final Prospectus” means the Statutory Prospectus that discloses the public offering price, other 430B Information and other final terms of the Offered Securities and otherwise satisfies Section 10(a) of the Act.

     “General Use Issuer Free Writing Prospectus” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being so specified in Schedule B to this Agreement.

     “Issuer Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433, relating to the Offered Securities in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

     “Limited Use Issuer Free Writing Prospectus” means any Issuer Free Writing Prospectus that is not a General Use Issuer Free Writing Prospectus.

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

     “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”).

     “Statutory Prospectus” with reference to any particular time means the prospectus relating to the Offered Securities that is included in the Registration Statement immediately prior to that time, including all 430B Information and all 430C Information with respect to the Registration Statement. For purposes of the foregoing definition, 430B Information shall be considered to be included in the Statutory Prospectus only as of the actual time that the form of prospectus (including a prospectus supplement) is filed with the Commission pursuant to Rule 424(b) and not retroactively.

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

     (b) Compliance with Securities Act Requirements. (i) (A) At the time the Registration Statement initially became effective, (B) at the time of each amendment thereto for the purposes of complying with Section 10(a)(3) of the Act (whether by post-effective amendment, incorporated report or form of prospectus), (C) at the Effective Time relating to the Offered Securities and (D) on the Closing Date, the Registration Statement conformed and will conform in all material respects to the requirements of the Act and the Rules and Regulations thereunder and did not and will not include any 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 not misleading; and (ii) (A) on its date, (B) at the time of filing the Final Prospectus pursuant to Rule 424(b) and (C) on the Closing Date, the Final Prospectus will conform in all material respects to the requirements of the Act and the Rules and Regulations, and will not include any untrue statement of a material fact or omit to state any 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. The preceding sentence does not apply to statements in or omissions from any such document based upon written information furnished to the Company by any Underwriter 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.

     (c) Automatic Shelf Registration Statement. (i) Well-Known Seasoned Issuer Status. (A) At the time of initial filing of the Registration Statement, (B) at the time of the most recent amendment thereto for the purposes of complying with Section 10(a)(3) of the Act (whether such amendment was by post-effective amendment, incorporated report filed pursuant to Section 13 or 15(d) of the Exchange Act or form of prospectus), and (C) at the time the Company or any person acting on its behalf (within the meaning, for this clause only, of Rule 163(c)) made any offer relating to the Offered Securities in reliance on the exemption of Rule 163, the Company was a “well known seasoned issuer” as defined in Rule 405, including not having been an “ineligible issuer” as defined in Rule 405.

	(ii)		Effectiveness of Automatic Shelf Registration Statement. The Registration Statement is an “automatic shelf registration statement,” as defined in Rule 405, that initially became effective within three years prior to the date of this Agreement. If immediately prior to the Renewal Deadline (as hereinafter defined), any of the Offered Securities remain unsold by the Underwriters, the Company will prior to the Renewal Deadline file, if it has not already done so and is eligible to do so, a new automatic shelf registration statement relating to the Offered Securities, in a form satisfactory to the Representatives. If the Company is no longer eligible to file an automatic shelf registration statement, the Company will prior to the Renewal Deadline, if it has not already done so, file a new shelf registration statement relating to the Offered Securities, in a form satisfactory to the Representatives, and will use its reasonable best efforts to cause such registration statement to be declared effective within 180 days after the Renewal Deadline. The Company will take all other action necessary or appropriate to permit the public offering and sale of the Offered Securities to continue as contemplated in the expired registration statement relating to the Offered Securities. “Renewal Deadline” means the third anniversary of the initial effective time of the Registration Statement.
	(iii)		Eligibility to Use Automatic Shelf Registration Form. The Company has not received from the Commission any notice pursuant to Rule 401(g)(2) objecting to use of the automatic shelf registration statement form. If at any time when Offered Securities remain unsold by the Underwriters the Company receives from the Commission a notice pursuant to Rule 401(g)(2) or otherwise ceases to be eligible to use the automatic shelf registration statement form, the Company will (i) promptly notify the Representatives, (ii) promptly file a new registration statement or post-effective amendment on the proper form relating to the Offered Securities, in a form satisfactory to the Representatives, (iii) use its reasonable best efforts to cause such registration statement or post-effective amendment to be declared effective as soon as practicable, and (iv) promptly notify the Representatives of such effectiveness. The Company will take all other action necessary or appropriate to permit the public offering and sale of the Offered Securities to continue as contemplated in the registration statement that was the subject of the Rule 401(g)(2) notice or for which the Company has otherwise become ineligible. References herein to the Registration Statement shall include such new registration statement or post-effective amendment, as the case may be.
	(iv)		Filing Fees. The Company has paid or shall pay the required Commission filing fees relating to the Offered Securities within the time required by Rule 456(b)(1) without regard to the proviso therein and otherwise in accordance with Rules 456(b) and 457(r).

     (d) Ineligible Issuer Status. (i) At the earliest time after the filing of the Registration Statement that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2)) of the Offered Securities and (ii) at the date of this Agreement, the Company was not and is not an “ineligible issuer,” as defined in Rule 405, including (x) the Company or any other subsidiary in the preceding three years not having been convicted of a felony or misdemeanor or having been made the subject of a judicial or administrative decree or order as described in Rule 405 and (y) the Company in the preceding three years not having been the subject of a bankruptcy petition or insolvency or similar proceeding, not having had a registration statement be the subject of a proceeding under Section 8 of the Act and not being the subject of a proceeding under Section 8A of the Act in connection with the offering of the Securities, all as described in Rule 405.

     (e) General Disclosure Package. As of the Applicable Time, neither (i) any General Use Issuer Free Writing Prospectus(es) issued at or prior to the Applicable Time, the preliminary prospectus supplement relating to the Offered Securities, dated June 2, 2009, including the base prospectus, dated June 2, 2009 (which is the most recent Statutory Prospectus distributed to investors generally) (the “Preliminary Prospectus”), and the other information, if any, stated in Schedule B to this Agreement to be included in the General Disclosure Package, all considered together (collectively, the “General Disclosure Package”), nor (ii) any individual Limited Use Issuer Free Writing Prospectus, 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 sentence does not apply to statements in or omissions from any preliminary prospectus supplement referenced above, any Statutory Prospectus or any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically 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 Section 8(b) hereof.

     (f) Issuer Free Writing Prospectuses. Each Issuer Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Offered Securities or until any earlier date that the Company notified or notifies the Representatives as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information then contained in the Registration Statement. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information then contained in the Registration Statement or as a result of which such Issuer Free Writing Prospectus, if republished immediately following such event or development, would include an untrue statement of a material fact or omitted or would 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, (i) the Company has promptly notified or will promptly notify the Representatives and (ii) the Company has promptly amended or will promptly amend or supplement such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically 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 Section 8(b) hereof.

     (g) 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 Delaware, with corporate power and authority to own its properties and conduct its business as described in the General Disclosure Package; 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 (except such failures to qualify that would not reasonably be expected to constitute, either individually or in the aggregate, a Material Adverse Effect (as defined below)).

     (h) Subsidiaries. Each subsidiary of the Company has been duly incorporated or formed, as the case may be, and is existing and in good standing under the laws of the jurisdiction of its incorporation or formation, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package; and each subsidiary is duly qualified to do business as a foreign corporation or limited liability company, as applicable, 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 such failures to qualify that would not reasonably be expected to constitute, either individually or in the aggregate, a Material Adverse Effect); all of the issued and outstanding shares and limited liability company interests, as applicable, of each subsidiary have been duly authorized and validly issued in accordance with the organizational documents of such subsidiary and is fully paid (to the extent required under such subsidiary’s organization documents) and nonassessable, except as such non-assessability may be affected by Section 18-303, 18-607 and 18-804 of the Delaware Limited Liability Company Act; and the shares and limited liability company interests owned by the Company, directly or through subsidiaries, are owned free from liens, encumbrances and defects other than (i) as described in the Registration Statement, the General Disclosure Package and the Final Prospectus and (ii) those created by or arising in connection with the Amended and Restated Credit Agreement, dated as of March 2, 2006, as amended, among the Company and Mariner Energy Resources, Inc., as borrowers, the lenders party thereto from time to time and Union Bank of California, N.A, as administrative agent and issuing lender.

     (i) Offered Securities. The outstanding shares of capital stock of the Company as of the date of this Agreement have been, and on each Closing Date will be, duly authorized and validly issued in accordance with the organizational documents of the Company and are fully paid and nonassessable; when the Offered Securities have been delivered and paid for in accordance with this Agreement on each Closing Date, such Offered Securities will have been duly authorized, validly issued, fully paid and nonassessable, will conform in all material respects to the information in the General Disclosure Package and to the description of such Offered Securities contained in the Final Prospectus; the stockholders of the Company have no preemptive rights with respect to the Securities; and none of the outstanding shares of capital stock of the Company has been issued in violation of any preemptive or similar rights of any security.

     (j) No Finder’s Fee. There are no contracts, agreements or understandings between the Company and any person (other than this Agreement) that would give rise to a valid claim against any of them or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Offered Securities.

     (k) Registration Rights. Except as disclosed in the General Disclosure Package and except for those agreements listed on Schedule E to this Agreement, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in the securities registered pursuant to a Registration Statement or in any securities being registered pursuant to any other registration statement filed by the Company under the Act (collectively, “registration rights”), and any person to whom the Company has granted registration rights has agreed not to or is not entitled to exercise such rights until after the expiration of the Lock-Up Period referred to in Section 5 hereof.

     (l) Listing. The Offered Securities have been approved for listing on The New York Stock Exchange, subject to notice of issuance.

     (m) Absence of Further Requirements. No consent, approval, authorization or order of, or filing or registration with, any person (including any governmental agency or body or any court) is required for the consummation of the transactions contemplated by this Agreement in connection with the offering, issuance and sale of the Offered Securities by the Company, except such as have been obtained, or made and such as may be required under state securities laws.

     (n) Title to Property. The Company or its subsidiaries have legal, valid and defensible title to substantially all the interests in oil and gas properties underlying the Company’s estimates of its net proved reserves contained in the General Disclosure Package and to substantially all other real and personal property reflected in the General Disclosure Package as assets owned by them, in each case free and clear of all liens, encumbrances and defects, except such as are described in the General Disclosure Package or as would not be reasonably expected to have a Material Adverse Effect; and any other real property and buildings held under lease by the Company or its subsidiaries are held by them under valid, subsisting and enforceable leases, with such exceptions as are not material and do not materially interfere with the use made and proposed to be made of such property and buildings by the Company or its subsidiaries; and the care taken by the Company and its subsidiaries with respect to acquiring or otherwise procuring such leases, options to lease, drilling rights and concessions or other property interests was generally consistent with standard industry practices in the areas in which the Company operates for acquiring or procuring leases and interests therein to explore, develop or produce hydrocarbons.

     (o) Absence of Defaults and Conflicts Resulting from Transaction. The execution, delivery and performance of this Agreement, the issuance and sale of the Offered Securities and compliance with the terms and provisions hereof (i) will not result in a breach or violation of any of the terms and provisions of, or constitute a default or a Debt Repayment Triggering Event (as defined below) under any indenture, mortgage, deed of trust, loan agreement, lease 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) will not result in any violation of the provisions of the charter or by-laws, limited liability company agreement, partnership agreement or similar organizational document of the Company or any of its subsidiaries or (iii) will not violate any statute or any order, rule or regulation of any court or governmental agency or body having jurisdiction over the Company or any of its subsidiaries or any of their properties or assets; except, in the case of clauses (i) and (iii) above, as would not reasonably be expected to have a Material Adverse Effect; a “Debt Repayment Triggering Event” means any event or condition that gives, or with the giving of notice or lapse of time would give, the holder of any note, debenture, or other evidence of indebtedness (or any person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or any of its subsidiaries.

     (p) Absence of Existing Defaults and Conflicts. Neither the Company nor any of its subsidiaries is (i) in violation of its respective charter, by-laws, certificate of formation or limited liability company agreement, (ii) in default (or with the giving of notice or lapse of time would be in default) under any existing obligation, agreement, covenant or condition contained in any indenture, loan agreement, mortgage, lease or other agreement or instrument to which any of them is a party or by which any of them is bound or to which any of the properties of any of them is subject or (iii) in violation of any law, ordinance, governmental rule, regulation or court decree to which it or its property or assets may be subject or has failed to obtain or maintain any material license, permit, certificate, franchise or other governmental authorization or permit necessary to the ownership of its property or to the conduct of its business except, in the case of clauses (ii) and (iii), as would not, individually or in the aggregate, result in a material adverse effect on the condition (financial or otherwise), stockholders’ equity, results of operations, business or properties of the Company and its subsidiaries taken as a whole (“Material Adverse Effect”).

     (q) No Restrictions on Subsidiaries. Except as disclosed in the Registration Statement or the General Disclosure Package, no subsidiary of the Company 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.

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

     (s) Absence of Labor Dispute. No labor dispute with the employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is imminent that in either case would reasonably be expected to have a Material Adverse Effect.

     (t) Environmental Laws. Except as disclosed in the General Disclosure Package, (i)(A) neither the Company nor any of its subsidiaries has received any notice that has not been resolved alleging that it is in violation of any federal, state, local or foreign statute, law, rule, regulation, ordinance, code, policy or any judicial or administrative interpretation thereof, including any judicial or administrative order, consent, decree or judgment, pertaining to pollution or protection of human health, the environment (including, without limitation, ambient air, surface water, groundwater, land surface or subsurface strata) or wildlife, including, without limitation, laws and regulations pertaining to the release or threatened release of chemicals, pollutants, contaminants, wastes, toxic substances, hazardous substances, petroleum or petroleum products, asbestos-containing materials or mold (collectively, “Hazardous Materials”) or to the manufacture, processing, distribution, use, treatment, storage, disposal, transport or handling of Hazardous Materials (collectively, “Environmental Laws”), (ii) the Company and its subsidiaries have all permits, authorizations and approvals required under any applicable Environmental Laws and are each in compliance with their requirements, (iii) there are no pending or, to the knowledge of the Company, threatened administrative, regulatory or judicial actions, suits, demands, demand letters, claims, liens, notices of noncompliance or violation, investigation or proceedings under any Environmental Law against the Company, or any of its subsidiaries, and (iv) to the knowledge of the Company, there are no events or circumstances that would reasonably be expected to form the basis of an order for clean-up or remediation, or an action, suit or proceeding by any private party or governmental body or agency, against or affecting the Company or any of its subsidiaries pertaining to Hazardous Materials or under any Environmental Laws.

     (u) Accurate Disclosure. The statements in the Statutory Prospectus under the heading “Description of Capital Stock,” insofar as they purport to constitute a summary of the terms of the Securities, and the statements in the Preliminary Prospectus and the Final Prospectus under the heading “Certain U.S. Federal Income and Estate Tax Considerations,” insofar as they purport to describe the provisions of the laws and documents referred to therein, are accurate in all material respects.

     (v) Absence of Manipulation. The Company has not taken, directly or indirectly, any action that is designed to or that has constituted or that would reasonably be expected to cause or result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Offered Securities.

     (w) Internal Controls and Compliance with the Sarbanes-Oxley Act. Except as set forth in the General Disclosure Package, the Company, its subsidiaries and the Company’s Board of Directors (the “Board”) are in compliance with Sarbanes-Oxley and all applicable Exchange Rules. The Company maintains a system of internal controls, including, but not limited to, disclosure controls and procedures, internal controls over accounting matters and financial reporting, an internal audit function and legal and regulatory compliance controls (collectively,

“Internal Controls”) that comply with the Securities Laws and are sufficient to provide reasonable assurances 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 U.S. General Accepted Accounting Principles and to maintain accountability for assets, (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. The Internal Controls are, or upon consummation of the offering of the Offered Securities will be, overseen by the Audit Committee (the “Audit Committee”) of the Board in accordance with Exchange Rules. The Company has not publicly disclosed or reported to the Audit Committee or the Board a material weakness, change in Internal Controls or fraud involving management or other employees who have a significant role in Internal Controls, any violation of, or failure to comply with, the Securities Laws, or any matter which, if determined adversely, would reasonably be expected to have a Material Adverse Effect. Within the next 90 days the Company does not reasonably expect to publicly disclose or report to the Audit Committee or the Board a material weakness, change in Internal Controls or fraud involving management or other employees who have a significant role in Internal Controls, any violation of, or failure to comply with, the Securities Laws, or any matter which, if determined adversely, would reasonably be expected to have a Material Adverse Effect. The Company is not aware of any significant deficiency that it reasonably expects to publicly disclose or report to the Audit Committee of the Board within the next 90 days.

     (x) Litigation. Except as disclosed in the General Disclosure Package, there are no legal or governmental proceedings pending to which the Company or any of its subsidiaries is a party or of which any property or assets of the Company or any of its subsidiaries is the subject that, if determined adversely to the Company or any of its subsidiaries, is reasonably likely to have a Material Adverse Effect, and to the knowledge of the Company, no such proceedings are threatened or contemplated by governmental authorities or threatened by others.

     (y) Financial Statements. The historical financial statements (including the related notes and schedules) included or incorporated by reference in the Registration Statement and the General Disclosure Package present fairly in all material respects the financial position of the Company and its consolidated subsidiaries as of the dates shown and their results of operations and cash flows for the periods shown, and such financial statements have been prepared in conformity with the generally accepted accounting principles in the United States applied on a consistent basis, except in each case as set forth or contemplated in the Registration Statement and the General Disclosure Package.

     (z) No Material Adverse Change in Business. Except as disclosed in the General Disclosure Package, since the end of the period covered by the latest audited financial statements included in the General Disclosure Package (i) there has been no change, nor any development or event involving a prospective change, in the condition (financial or otherwise), stockholders’ equity, results of operations, business or properties of the Company and its subsidiaries, taken as a whole, that is material and adverse, (ii) except as disclosed in or contemplated by the General Disclosure Package, there has been no dividend or distribution of any kind declared, paid or made by the Company or any of its subsidiaries on any class of their capital stock and (iii) except as disclosed in or contemplated by the General Disclosure Package, there has been no material adverse change in the capital stock, short-term indebtedness, long-term indebtedness, net current assets or net assets of the Company and any of its subsidiaries.

     (aa) 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, will not be an “investment company” as defined in the Investment Company Act of 1940, as amended (the “Investment Company Act”).

     (bb) 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.

     (cc) Independent Accountants. Deloitte & Touche LLP, who have certified certain financial statements of the Company, whose report is incorporated by reference into the General Disclosure Package, were independent registered public accountants as required by the Act and rules and regulations promulgated thereunder and the rules and regulations promulgated by the Public Company Accounting Oversight Board during the periods covered by the financial statements on which they reported contained in the General Disclosure Package.

     (dd) Independent Reserve Engineers. Ryder Scott Company, L.P. (“Ryder Scott”), whose reports are referenced in the General Disclosure Package (collectively, the “Reserve Reports”) was, as of the date of each of the Reserve Reports, and is, as of the date hereof, an independent reserve engineer with respect to the Company. No information has come to the attention of the Company or, to the Company’s knowledge, to Ryder Scott, that would reasonably be expected to cause Ryder Scott to withdraw its Reserve Reports.

     (ee) Reserve Reports. The oil and gas reserve estimates of the Company and its subsidiaries as of December 31, 2008, 2007 and 2006 contained in the General Disclosure Package are based on estimates made in reserve reports prepared by an independent petroleum engineering firm as set forth in the General Disclosure Package, such reserve estimates fairly reflect the oil and gas reserves of the Company and its subsidiaries at the dates indicated in the General Disclosure Package and are in accordance with Commission guidelines applied on a consistent basis throughout the periods involved. The information underlying the estimates described above that was supplied to Ryder Scott for the purposes of preparing the reserve report and audit referred to above, including production and costs of operation, was true and correct in all material respects on the dates such estimates were made, and such information was supplied and was prepared in accordance with customary industry practices; other than normal production of the reserves, product price fluctuations, fluctuations of demand for such products, hurricanes, loop currents and other adverse weather conditions, unavailability or increased costs of rigs, equipment, supplies or personnel, the timing of third party operations and other factors disclosed in the General Disclosure Package, the Company is not aware of any facts or circumstances that would result in a material adverse change in the aggregate net reserves, or the present value of the future net cash flows therefrom as described in the General Disclosure Package and as reflected in the reserve reports; the estimates of such reserves and present value as described in the General Disclosure Package and reflected in the reserve reports referenced therein have been prepared in a manner that complies with the applicable requirements of the rules under the Act with respect to proved reserves.

     (ff) Taxes. The Company and its subsidiaries have filed all federal, state and local tax returns that are required to be filed through the date hereof or have requested extensions thereof (except in any case in which the failure so to file would not reasonably be expected to have a Material Adverse Effect); and, except as set forth in the General Disclosure Package, the Company and its subsidiaries have paid all taxes (including any assessments, fines or penalties) required to be paid by them, except for any such taxes, assessments, fines or penalties currently being contested in good faith or as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect.

     (gg) Insurance. The Company and each of its subsidiaries carry, or are covered by, insurance in such amounts and covering such risks as is adequate for the conduct of their respective businesses and the value of their respective properties and as is customary for companies engaged in similar businesses in similar industries.

     (hh) ERISA. The Company is in compliance in all material respects with all presently applicable provisions of the Employee Retirement Income Security Act of 1974, as amended, including the regulations and published interpretations thereunder (“ERISA”); no “reportable event” (as defined in ERISA) has occurred with respect to any “pension plan” (as defined in ERISA) for which the Company or any subsidiary would have any liability; neither the Company nor any subsidiary has incurred or expects to incur liability under (i) Title IV of ERISA with respect to termination of, or withdrawal from, any “pension plan” or (ii) Sections 412 or 4971 of the Internal Revenue Code of 1986, as amended, including the regulations and published interpretations thereunder (the “Code”); and each “pension plan” for which the Company or any subsidiary would have any liability that is intended to be qualified under Section 401(a) of the Code is so qualified in all material respects and nothing has occurred, whether by action or by failure to act, which would cause the loss of such qualification.

     (ii) Additional Obligations. Since the latest date as of which information is given in the General Disclosure Package through the date hereof, and except as may otherwise be disclosed in the General Disclosure Package, neither the Company nor any subsidiary has (i) issued or granted any securities (other than issuances of restricted stock or options under the Company’s equity plans), (ii) incurred any liability or obligation, direct or contingent, other than liabilities and obligations that were incurred in the ordinary course of business, (iii) entered into any transaction not in the ordinary course of business or (iv) declared or paid any dividend on its capital stock.

     (jj) Margin Rules. None of the transactions contemplated by this Agreement (including, without limitation, the use of the proceeds from the sale of the Offered Securities), will violate or result in a violation of Section 7 of the Exchange Act, or any regulation promulgated thereunder, including, without limitation, Regulations T, U and X of the Board of Governors of the Federal Reserve System.

     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 Underwriters, and each of the Underwriters agrees, severally and not jointly, to purchase from the Company, at a purchase price of $13 ###-###-#### per share, the respective number of shares of Firm Securities set forth opposite the names of the Underwriters in Schedule A hereto.

     The Company will deliver the Firm Securities to, or as instructed by, the Representatives for the accounts of the several Underwriters in a form reasonably acceptable to the Representatives against payment of the aggregate purchase price described in the preceding paragraph by the Underwriters 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 Akin Gump Strauss Hauer & Feld LLP, at 10:00 A.M., New York time, on June 10, 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”. For purposes of Rule 15c6-1 under the Exchange Act, the First Closing Date (if later than the otherwise applicable settlement date) shall be the settlement date for payment of funds and delivery of securities for all the Offered Securities sold pursuant to the offering. The Firm Securities so to be delivered or evidence of their issuance will be made available for checking at the above office 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 the Final Prospectus, the Underwriters may purchase all or less than all of the Optional Securities at the purchase price per Security to be paid for the Firm Securities. The Company agrees to sell to the Underwriters the number of shares of Optional Securities specified in such notice and the Underwriters agree, severally and not jointly, to purchase such Optional Securities, as applicable. Such Optional Securities shall be purchased for the account of each Underwriter in the same proportion as the number of shares of Firm Securities set forth opposite such Underwriter’s name bears to the number of shares of Firm Securities (subject to adjustment by the Representatives to eliminate fractions), and may be purchased by the Underwriters only for the purpose of covering over-allotments

made in connection with the sale of the Firm Securities. 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 an “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 but shall be not later than five full business days after written notice of election to purchase such Optional Securities is given. The Company will deliver the applicable Optional Securities being purchased on each Optional Closing Date to or as instructed by the Representatives for the accounts of the several Underwriters in a form reasonably acceptable to the Representatives against payment of the purchase price therefor 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 Akin Gump Strauss Hauer & Feld LLP. The Optional Securities being purchased on each Optional Closing Date or evidence of their issuance will be made available for checking at the office of Akin Gump Strauss Hauer & Feld LLP at a reasonable time in advance of such Optional Closing Date.

     4. Offering by Underwriters. It is understood that the several Underwriters propose to offer the Offered Securities for sale to the public as set forth in the Final Prospectus.

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

     (a) Filing of Prospectuses. The Company has filed or will file each Statutory Prospectus (including the Final Prospectus) pursuant to and in accordance with Rule 424(b) not later than the second business day following the earlier of the date it is first used or the execution and delivery of this Agreement. The Company has complied and will comply with Rule 433.

     (b) Filing of Amendments; Response to Commission Requests. The Company will promptly advise the Representatives of any proposal to amend or supplement the Registration Statement or any Statutory Prospectus at any time and will offer the Representatives a reasonable opportunity to comment on any such amendment or supplement; and the Company will also advise the Representatives promptly of (i) the filing of any such amendment or supplement, (ii) any request by the Commission or its staff for any amendment to the Registration Statement, for any supplement to any Statutory Prospectus or for any additional information, (iii) the institution by the Commission of any stop order proceedings in respect of the Registration Statement or the threatening of any proceeding for that purpose, and (iv) the receipt by the Company of any notification with respect to the suspension of the qualification of the Offered Securities in any jurisdiction or the institution or threatening of any proceedings for such purpose. The Company will use its reasonable best efforts to prevent the issuance of any such stop order or the suspension of any such qualification and, if issued, to obtain as soon as possible the withdrawal thereof.

     (c) Continued Compliance with Securities Laws. If, at any time when a prospectus relating to the Offered Securities is (or but for the exemption in Rule 172 would be) required to be delivered under the Act by any Underwriter or dealer, any event occurs as a result of which the Final Prospectus as then amended or supplemented would include an 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, or if it is necessary at any time to amend the Registration Statement or supplement the Final Prospectus to comply with the Act, the Company will promptly notify the Representatives of such event and will promptly prepare and file with the Commission and furnish, at its own expense, to the Underwriters and the dealers and any other dealers upon request of the Representatives, an amendment or supplement

which will correct such statement or omission or an amendment which will effect such compliance. Neither the Representatives’ consent to, nor the Underwriters’ delivery of, any such amendment or supplement shall constitute a waiver of any of the conditions set forth in Section 7 hereof.

     (d) Rule 158. As soon as practicable, but not later than 16 months, after the date of this Agreement, the Company will make generally available to its securityholders an earnings statement covering a period of at least 12 months beginning after the date of this Agreement and satisfying the provisions of Section 11(a) of the Act and Rule 158.

     (e) Furnishing of Prospectuses. The Company will furnish to the Representatives copies of the Registration Statement, including all exhibits, any Statutory Prospectus, the Final Prospectus and all amendments and supplements to such documents, in each case as soon as reasonably available and in such quantities as the Representatives reasonably request. The Company will pay the expenses of printing and distributing to the Underwriters all such documents.

     (f) Blue Sky Qualifications. The Company will arrange for the qualification of the Offered Securities for sale under the laws of such jurisdictions as the Representatives shall reasonably designate and will continue such qualifications in effect so long as required for the distribution; 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) Reporting Requirements. During the period of three years hereafter, the Company will furnish to the Representatives and, upon request, to each of the other Underwriters, as soon as practicable after the end of each fiscal year, a copy of its annual report to stockholders for such year; and the Company will furnish to the Representatives (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 stockholders, and (ii) from time to time, such other information concerning the Company or its outstanding securities to the extent relevant to the offering contemplated by this Agreement as the Representatives 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, it is not required to furnish such reports or statements to the Underwriters.

     (h) Payment of Expenses. The Company will pay all expenses incident to the performance of its obligations under this Agreement, including but not limited to any filing fees and other expenses incurred by it in connection with qualification of the Offered Securities for sale under the laws of such jurisdictions as the Representatives shall reasonably designate (including fees and disbursements of counsel to the Underwriters in respect of such qualifications) and the preparation and printing of memoranda relating thereto, any fees charged by investment rating agencies for the rating of the Offered Securities, costs and expenses relating to investor presentations or 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, fees and expenses incident to listing the Offered Securities on the New York Stock Exchange, NYSE Amex Equities, NASDAQ Stock Market and other national and foreign exchanges, fees and expenses in connection with the registration of the Offered Securities under the Exchange Act, and expenses incurred in distributing preliminary prospectuses and the Final Prospectus (including any amendments and supplements thereto) to the Underwriters and for expenses incurred for preparing, printing and distributing any Issuer Free Writing Prospectuses to investors or prospective investors.

     (i) Use of Proceeds. The Company will use the net proceeds received in connection with the offering of the Offered Securities in the manner described in the General Disclosure Package. Except as disclosed in the General Disclosure Package, 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 Underwriter.

     (j) Absence of Manipulation. The Company will not take, directly or indirectly, any action designed to or that would constitute or that might reasonably be expected to cause or result in, stabilization or manipulation of the price of any securities of the Company to facilitate the sale or resale of the Offered Securities.

     (k) Restriction on Sale of Securities by Company. For the period specified below (the “Lock-Up Period”), the Company will not, directly or indirectly, take any of the following actions with respect to its Securities or any securities convertible into or exchangeable or exercisable for any of its Securities (“Lock-Up Securities”): (i) offer, sell, issue, contract to sell, pledge or otherwise dispose of Lock-Up Securities, (ii) offer, sell, issue, contract to sell, contract to purchase or grant any option, right or warrant to purchase Lock-Up Securities, (iii) enter into any swap, hedge or any other agreement that transfers, in whole or in part, the economic consequences of ownership of Securities, (iv) establish or increase a put equivalent position or liquidate or decrease a call equivalent position in Lock-Up Securities within the meaning of Section 16 of the Exchange Act or (v) file with the Commission a registration statement under the Act relating to Lock-Up Securities, or publicly disclose the intention to take any such action, without the prior written consent of Credit Suisse Securities (USA) LLC (“Credit Suisse”), except (a) the sale by the Company of the Offered Securities hereunder, (b) issuance of Lock-Up Securities pursuant to the exercise by directors, employees or consultants (or their estates or other permitted successors in interest) of stock options or other equity awards outstanding on the date hereof, (c) grants of stock options, restricted stock or other equity awards pursuant to the terms of a plan in effect on the date hereof covering directors, employees or consultants, and (d) the issuance of shares of Securities or other rights to acquire Securities that the Company may issue in connection with acquisitions, provided that the aggregate number of shares of Securities so issued, or issuable upon exercise, exchange or conversion of any rights to acquire Securities, under clause (d) shall not exceed 5% of the outstanding Securities on the date hereof. The initial Lock-Up Period will commence on the date hereof and continue for 60 days after the date hereof or such earlier date that Credit Suisse consents to in writing.

     (l) Restriction on Sale of Securities by Officers and Directors. The Company has caused each officer and director of the Company to furnish to the Representatives, on or prior to the date of this Agreement, a letter or letters, in form and substance satisfactory to the Underwriters, pursuant to which each such person shall agree not to (i) offer, sell, contract to sell, pledge or otherwise dispose of, directly or indirectly, any Lock-Up Securities, (ii) enter into a transaction which would have the same effect, or enter into any swap, hedge or other arrangement that transfers, in whole or in part, any of the economic consequences of ownership of Lock-Up Securities, whether any such aforementioned transaction is to be settled by delivery of the Securities or such other securities, in cash or otherwise, or (iii) publicly disclose the intention to make any such offer, sale, pledge or disposition, or to enter into any such transaction, swap, hedge or other arrangement, without, in each case, the prior written consent of Credit Suisse, during the Lock-Up Period (the “Lock-Up Agreements”), except for Securities acquired in the open market and transfers to family members or a trust, so long as such parties agree to be locked-up for the remainder of the Lock-Up Period. Notwithstanding anything herein to the contrary, the restrictions in this Section 5(l) do not apply to any transactions effected pursuant to a trading plan entered into by any officer or director pursuant to Rule 10b5-1 under the Exchange Act prior to the date hereof and shall not prevent any officer or director from entering into one or more new 10b5-1 trading plans or renewing or amending one or more existing 10b5-1 trading plans as long as there are no sales of the Securities under such new, amended or renewed plans during the Lock-Up Period. Additionally, the restrictions in this Section 5(l) shall not apply to any withholding by the

Company of Securities for the purpose of satisfying tax liabilities of the undersigned associated with the vesting or exercise of awards of the undersigned granted pursuant to an equity plan of the Company existing as of the date hereof.

     6. Free Writing Prospectuses. (a) Issuer Free Writing Prospectuses. The Company represents and agrees that, unless it obtains the prior consent of the Representatives, and each Underwriter represents and agrees that, unless it obtains the prior consent of the Company and the Representatives, it has not made and will not make any offer relating to the Offered Securities that would constitute an Issuer Free Writing Prospectus, or that would otherwise constitute a “free writing prospectus,” as defined in Rule 405, required to be filed with the Commission. Any such free writing prospectus included on Schedule B or consented to by the Company and the Representatives is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company represents that it has treated and agrees that it will treat each Permitted Free Writing Prospectus as an “issuer free writing prospectus,” as defined in Rule 433, and has complied and will comply with the requirements of Rules 164 and 433 applicable to any Permitted Free Writing Prospectus, including timely Commission filing where required, legending and record keeping.

     (b) Term Sheets. The Company will prepare a final term sheet relating to the Offered Securities in the form of final term sheet attached to Schedule B hereto, and otherwise in a form consented to by the Representatives, and will file such final term sheet within the period required by Rule 433(d)(5)(ii) following the date such final terms have been established for the Offered Securities. Any such final term sheet is an Issuer Free Writing Prospectus and a Permitted Free Writing Prospectus for purposes of this Agreement. The Company also consents to the use by any Underwriter of a free writing prospectus substantially in the form of the final term sheet attached to Schedule B hereto or that contains only (i)(x) information describing the preliminary terms of the Offered Securities or their offering or (y) information that describes the final terms of the Offered Securities or their offering and that is included in the final term sheet of the Company contemplated in the first sentence of this subsection or (ii) other information that is not “issuer information,” as defined in Rule 433, it being understood that any such free writing prospectus referred to in clause (i) or (ii) above shall not be an Issuer Free Writing Prospectus for purposes of this Agreement.

     7. Conditions of the Obligations of the Underwriters. The obligations of the several Underwriters to purchase and pay for the Firm Securities on the First Closing Date and the Optional Securities to be purchased 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 Company officers made pursuant to the provisions hereof, to the performance by the Company of their respective obligations hereunder and to the following additional conditions precedent:

     (a) Accountants’ Comfort Letter. The Representatives shall have received letters, dated, respectively, the date hereof and each Closing Date, of Deloitte & Touche LLP 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 C hereto (except that, in any letter dated a Closing Date, the specified date referred to in Schedule C hereto shall be a date no more than three days prior to such Closing Date).

     (b) Reserve Engineer’s Letters. The Representatives shall have received letters dated, respectively, the date hereof and the Closing Date, of Ryder Scott (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 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 Representatives.

     (c) Filing of Prospectus. The Final Prospectus shall have been filed with the Commission in accordance with the Rules and Regulations and Section 5(a) hereof. No stop order

suspending the effectiveness of the Registration Statement or of any part thereof shall have been issued and no proceedings for that purpose shall have been instituted or, to the knowledge of the Company or any Underwriter, shall be contemplated by the Commission.

     (d) 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), stockholders’ equity, results of operations, business or properties 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 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 of the Company (other than an announcement with positive implications of a possible upgrading, and no implication of a possible downgrading, of such rating) or any announcement that the Company has been placed on negative outlook; (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 any setting of minimum or maximum prices for trading on such exchange; (v) or 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 impractical or inadvisable to market the Offered Securities or to enforce contracts for the sale of the Offered Securities.

     (e) Opinion of Counsel for Company. The Representatives shall have received an opinion, dated such Closing Date, of Baker Botts L.L.P., counsel for the Company, substantially in the form of Schedule D hereto.

     (f) Opinion of Counsel for Underwriters. The Representatives shall have received from Akin Gump Strauss Hauer & Feld LLP, counsel for the Underwriters, such opinion or opinions, dated such Closing Date, with respect to such matters as the Representatives may require, and the Company shall have furnished to such counsel such documents as they may reasonably request for the purpose of enabling them to pass upon such matters.

     (g) Officer’s Certificate. The Representatives shall have received certificates, 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; the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to such Closing Date; no stop order suspending the effectiveness of the Registration Statement has been issued and no proceedings for that purpose have been instituted or, to the best of their knowledge after reasonable investigation, are contemplated by the Commission; and, subsequent to the date of the most recent financial statements in the General Disclosure Package, 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 or as described in such certificate.

     (h) Lock-Up Agreements. The Representatives shall have received the Lock-Up Agreements described in Section 5(l) on or prior to the date of this Agreement, each of which shall be in full force and effect.

     (i) Good Standing. The Representatives shall have received on and as of each Closing Date evidence of the good standing of the Company and its subsidiaries in their respective jurisdictions of organization and their good standing in such other jurisdictions as the Representatives may reasonably request, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

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

     8. Indemnification and Contribution. (a) Indemnification of Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its partners, members, directors, officers, employees, agents, affiliates and each person, if any, who controls such Underwriter within the meaning of Section 15 of the 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 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 any part of the Registration Statement at any time, any Statutory Prospectus as of any time, the Final Prospectus or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or alleged omission of a material fact required to be stated therein or necessary to make the statements therein (with respect to any Statutory Prospectus or the Final Prospectus, in light of the circumstance in 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 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 Underwriter through the Representatives specifically 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 Company. Each Underwriter will severally and not jointly indemnify and hold harmless the Company, each of its directors and each of its officers who signs a Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Act or Section 20 of the Exchange Act (each, an “Underwriter Indemnified Party”), against any losses, claims, damages or liabilities to which such Underwriter Indemnified Party may become subject, under the 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 any part of the Registration Statement at any time, any Statutory Prospectus as of any time, the Final Prospectus, or any Issuer Free Writing Prospectus, or arise out of or are based upon the omission or the alleged omission of a material fact required to be stated therein or necessary to make the statements therein (with respect to any Statutory Prospectus or the Final Prospectus, in light of the circumstance in 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 Underwriter through the Representatives

specifically for use therein, and will reimburse any legal or other expenses reasonably incurred by such Underwriter Indemnified Party in connection with investigating or defending against any such loss, claim, damage, liability, action, litigation, investigation or proceeding whatsoever (whether or not such Underwriter 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 Underwriter consists of the following information in each Statutory Prospectus and the Final Prospectus furnished on behalf of each Underwriter: (A) (i) the concession figure appearing in the fourth paragraph; and (ii) the information contained in the fourteenth paragraph relating to stabilizing transactions, syndicate short positions, syndicate covering transactions and penalty bids, in each case under the heading “Underwriting” and (B) the delivery date of the securities on the cover page of the Final Prospectus.

     (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; but 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 by such failure. 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 reasonably 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 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. It is understood and agreed that the indemnifying party shall not be liable for the fees and expenses of more than one separate counsel in any one action or series of related actions in the same jurisdiction representing the indemnified parties who are parties to such action. 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 (i) includes 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 a failure to act by or on behalf of an 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), (b) or (c) 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), (b) or (c) above (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 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 Underwriters 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 Underwriters 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 underwriting discounts and commissions received by the Underwriters. 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 Underwriters 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 Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Offered Securities underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages which 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 Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this subsection (d) to contribute are several in proportion to their respective underwriting obligations and not joint. The Company and the Underwriters 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 Underwriters 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 Underwriters. If any Underwriter or Underwriters default in their obligations to purchase Offered Securities hereunder on either the First Closing Date or any Optional Closing Date and the number of shares of Offered Securities that such defaulting Underwriter or Underwriters agreed but failed to purchase does not exceed 10% of the total number of shares of Offered Securities that the Underwriters 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 Underwriters, but if no such arrangements are made by such Closing Date, the non-defaulting Underwriters shall be obligated severally, in proportion to their respective commitments hereunder, to purchase the Offered Securities that such defaulting Underwriters agreed but failed to purchase on such Closing Date. If any Underwriter or Underwriters so default and the number of shares 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 Underwriters 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 Underwriter 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 will not terminate as to the Firm Securities or any Optional Securities purchased prior to such termination). As used in this Agreement, the term “Underwriter” includes any person substituted for an Underwriter under this Section. Nothing herein will relieve a defaulting Underwriter from liability for its default.

     10. Survival of Certain Representations and Obligations. The respective indemnities, agreements, representations, warranties and other statements of the Company or their respective officers and of the several Underwriters 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 Underwriter, 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 the purchase of the Offered Securities by the Underwriters is not consummated for any reason other than solely because of the termination of this Agreement pursuant to Section 9 hereof, the Company will reimburse the Underwriters for all out-of-pocket expenses (including fees and disbursements of counsel) reasonably incurred by them in connection with the offering of the Offered Securities, and the respective obligations of the Company and the Underwriters pursuant to Section 8 hereof shall remain in effect. In addition, 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.

     11. Notices. All communications hereunder will be in writing and, if sent to the Underwriters, will be mailed, delivered or telegraphed and confirmed to the Representatives, c/o Credit Suisse Securities (USA) LLC, Eleven Madison Avenue, New York, N.Y. 10010-3629, Attention: LCD-IBD, or, if sent to the Company, will be mailed, delivered or telegraphed and confirmed to it at One BriarLake Plaza, Suite 2000, 2000 West Sam Houston Parkway South, Houston, TX 77042, Attention: General Counsel; provided, however, that any notice to an Underwriter pursuant to Section 8 will be mailed, delivered or telegraphed and confirmed to such Underwriter.

     12. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and controlling persons referred to in Section 8, and no other person will have any right or obligation hereunder.

     13. Representation of Underwriters. The Representatives will act for the several Underwriters in connection with this financing, and any action under this Agreement taken by the Representatives will be binding upon all the Underwriters.

     14. 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.

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

     (a) No Other Relationship. The Representatives have been retained solely to act as an underwriter in connection with the sale of Offered Securities and no fiduciary, advisory or agency relationship between the Company and the Representatives has been created in respect of any of the transactions contemplated by this Agreement or the Final Prospectus, irrespective of whether the Representatives have advised or are advising the Company on other matters;

     (b) Arms’-Length Negotiations. The price of the Offered Securities set forth in this Agreement was established by the Company following discussions and arms’-length negotiations with the Representatives 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 the Representatives and their affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company and that the Representatives have no obligation to disclose such interests and transactions to the Company by virtue of any fiduciary, advisory or agency relationship; and

     (d) Waiver. The Company waives, to the fullest extent permitted by law, any claims it may have against the Representatives for breach of fiduciary duty or alleged breach of fiduciary duty and agrees that the Representatives shall have no 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 stockholders, employees or creditors of the Company.

     16. 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.

[Signature Pages to Follow]

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

[Signature Page to Underwriting Agreement]

[Signature Page to Underwriting Agreement]

SCHEDULE A

		Number of
Underwriter		Firm Securities
Credit Suisse Securities (USA) LLC			4,023,000
J.P. Morgan Securities Inc.			1,340,999
Merrill Lynch, Pierce, Fenner & Smith Incorporated			1,340,999
Wachovia Capital Markets, LLC			766,000
Citigroup Global Markets Inc.			361,286
Jefferies & Company, Inc.			361,286
Howard Weil Incorporated			361,286
Tudor, Pickering, Holt & Co. Securities, Inc.			361,286
Calyon Securities (USA) Inc.			361,286
Capital One Southcoast, Inc.			361,286
Natixis Bleichroeder Inc.			361,286
Total			10,000,000

SCHEDULE B

1.

General Use Free Writing Prospectuses (included in the General Disclosure Package)

     “General Use Issuer Free Writing Prospectus” includes each of the following documents:

	1.		Final term sheet, dated June 4, 2009, a copy of which is attached hereto, filed by the Company on June 5, 2009.
	2.		Free Writing Prospectus filed by the Company on June 3, 2009.

2.

Other Information Included in the General Disclosure Package

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

     None.

10,000,000 Shares of Common Stock
Par Value $0.0001 Per Share

     This term sheet to the preliminary prospectus supplement dated June 2, 2009 should be read together with the preliminary prospectus supplement before making a decision in connection with an investment in the securities. The information in this term sheet supersedes the information in the preliminary prospectus supplement to the extent that it is inconsistent therewith. Terms used but not defined herein have the meaning ascribed to them in the preliminary prospectus supplement.

Issuer:		Mariner Energy, Inc.
Size:		10,000,000 shares (11,500,000 shares including over-allotment option) (the “Equity Offering”)
Price to Public:		$14.50 per share
Gross Spread:		$0 ###-###-#### per share
Net Proceeds to Mariner (Before Expenses):		$138,852,635 ($159,680,530 including over-allotment option)
Last reported sale price (June 4, 2009):		$14.65 per share
Pricing Date/Closing Date:		June 4, 2009 / June 10, 2009
Joint Book-Running Managers:		Credit Suisse Securities (USA) LLC J.P. Morgan Securities Inc. Merrill Lynch, Pierce, Fenner & Smith Incorporated
Senior Co-Managers:		Wachovia Capital Markets, LLC
Co-Managers:		Citigroup Global Markets Inc. Jefferies & Company, Inc. Howard Weil Incorporated Tudor, Pickering, Holt & Co. Securities, Inc. Calyon Securities (USA) Inc. Capital One Southcoast, Inc. Natixis Bleichroeder Inc.

Concurrent Offering of Notes

     On June 4, 2009, we priced a separate public offering (the “Notes Offering”) of $300,000,000 aggregate principal amount of 11.75% Senior Notes due 2016 (the “Senior Notes”). The net proceeds of the Notes Offering, after deducting the underwriting discounts and commissions, will be $285,540,000. The Senior Notes were sold at 97.093% of their face amount and therefore carry original issue discount. As of March 31, 2009, after giving effect to the Notes Offering and the Equity Offering and the application of the estimated proceeds therefrom, we had $216.8 million of borrowings outstanding under our bank credit facility. The closing of the Notes Offering is not conditioned upon the completion of the Equity Offering.

     The issuer has filed a registration statement (including a base prospectus) with the SEC for the Notes Offering and the Equity Offering to which this communication relates. Before you invest, you should read the applicable prospectus supplements and the base prospectus in the registration statement and other documents the issuer has filed with the SEC for more complete information about the issuer, the Notes Offering and the Equity Offering. You may get these documents for free by visiting EDGAR on the SEC Web site at www.sec.gov. Alternatively, the prospectus supplement and the accompanying

prospectus may be obtained if you request it by contacting Credit Suisse Securities (USA) LLC, Prospectus Department, One Madison Avenue, New York, NY 10010 or by calling ###-###-####; J.P. Morgan Securities Inc., 4 Chase Metrotech Center, CS Level, Brooklyn, NY 11245, Attn: Chase Distribution and Support Service, Northeast Statement Processing, or by calling ###-###-####, or by faxing to ###-###-####; or Merrill Lynch & Co., Attn: Prospectus Department, 4 World Financial Center, New York, NY 10080, or by calling ###-###-####.

     Any disclaimer or other notice that may appear below is not applicable to this communication and should be disregarded. Such disclaimer or notice was automatically generated as a result of this communication being sent by Bloomberg or another email system.

SCHEDULE C
FORM OF AUDITOR’S LETTER

     The Representatives shall have received letters, dated, respectively, the date hereof and the First Closing Date, of Deloitte & Touche LLP 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 Registration Statements and the General Disclosure Package comply as to form in all material respects with the applicable accounting requirements of the Securities Laws;

     (ii) with respect to the period covered by the unaudited quarterly consolidated financial statements included in the Registration Statement and the General Disclosure Package, 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 Registration Statement and the General Disclosure Package, 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 stockholders, 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 Registration Statement and the General Disclosure Package; and on the basis thereof, nothing came to their attention which caused them to believe that:

     (A) the unaudited financial statements included in the Registration Statement or the General Disclosure Package 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 General Disclosure Package, at April 30, 2009, there were any increases in the short-term debt or long-term debt of the Company and its consolidated subsidiaries, or any change in stockholders’ equity or the consolidated capital stock of the Company and its consolidated subsidiaries or any decreases in the net current assets or net assets of the Company and its consolidated subsidiaries, as compared with the amounts shown on the latest balance sheet included in the General Disclosure Package; or for the period from the day after the date of the most recent unaudited quarterly consolidated financial statements for such entities included in the General Disclosure Package to April 30, 2009, there were any decreases, as compared with the corresponding period in the preceding year, in consolidated net sales, or net operating income, or in the total or per share amounts of consolidated net income or in the ratio of earnings to fixed charges of the Company and its consolidated subsidiaries, except for such changes, increases or decreases set forth in such letter which the General Disclosure Package discloses 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 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 stockholders’ equity or the consolidated capital stock of the Company and its consolidated subsidiaries or any decreases in the net current assets or net assets 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 General Disclosure Package; or for the period from the day after the date of the most recent unaudited quarterly financial statements for such entities included in the General Disclosure Package to such specified date, there were any decreases, as compared with the corresponding period in the preceding year, in net sales, or net operating income, or in the total or per share amounts of consolidated net income or in the ratio of earnings to fixed charges of the Company and its consolidated subsidiaries 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, increase, or decrease, except for such changes, increases or decreases set forth in such letter which the General Disclosure Package discloses 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 Registration Statement, each Issuer Free Writing Prospectus (other than any Issuer Free Writing Prospectus that is an “electronic road show,” as defined in Rule 433(h)) and the General Disclosure Package (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.

     All financial statements and schedules included in material incorporated by reference into the Registration Statement or the General Disclosure Package shall be deemed included in the Registration Statement or the General Disclosure Package for purposes of this Schedule.

SCHEDULE D
FORM OF OPINION OF COUNSEL FOR THE COMPANY

     (i) Good Standing of the Company. The Company has been duly incorporated and is existing and in good standing under the General Corporation Law of the State of Delaware, as amended, with corporate power and authority to own its properties and conduct its business as described in the General Disclosure Package, each in all material respects; and the Company is duly qualified to do business as a foreign corporation in good standing in each jurisdictions set forth opposite its name on Exhibit A hereto;

     (ii) Subsidiaries. Each subsidiary of the Company has been duly formed and is existing and in good standing under the General Corporation Law of the State of Delaware or the Delaware LLC Act, as applicable, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package, each in all material respects; and each subsidiary is duly qualified to do business as a foreign corporation or limited liability company, as applicable, in good standing in each of the jurisdictions set forth opposite its name on Exhibit A hereto; all of the issued and outstanding shares and limited liability company interests, as applicable, of the subsidiaries are owned directly or indirectly by the Company, free from liens, encumbrances equities or claims (A) in respect of which a financing statement under the Uniform Commercial Code of the States of Delaware, Louisiana or Texas naming the such subsidiary as a debtor is on file as of a recent date in the office of the Secretary of State of the States of Delaware, Louisiana or Texas or (B) otherwise known to us, without independent investigation, in each case, other than liens in connection with the Amended and Restated Credit Agreement, dated as of March 2, 2006, as amended, among the Company and Mariner Energy Resources, Inc., as borrowers, the lenders party thereto from time to time and Union Bank of California, N.A, as administrative agent and issuing lender;

     (iii) Offered Securities; Capitalization. The Offered Securities delivered on such Closing Date have been duly authorized and, when issued and delivered to the Underwriters against payment therefor in accordance with the terms of this Agreement, will be validly issued, fully paid and nonassessable, conform in all material respects to the information in the General Disclosure Package and to the description of such Offered Securities contained in the Final Prospectus; the authorized equity capitalization of the Company is as set forth in the General Disclosure Package; all of the outstanding shares of capital stock of the Company have been duly authorized and validly issued and are fully paid and non-assessable; the stockholders of the Company have no preemptive rights with respect to the Securities under the Company’s Second Amended and Restated Certificate of Incorporation, as amended, and Fourth Amended and Restated Bylaws, the General Corporation Law of the State of Delaware or, to the knowledge of such counsel without independent investigation, any other agreement or instrument to which the Company or any stockholder is a party; and none of the Securities outstanding prior to the issuance of the Offered Securities has been issued in violation of any preemptive or similar rights under the Company’s Second Amended and Restated Certificate of Incorporation, as amended, and Fourth Amended and Restated Bylaws, the General Corporation Law of the State of Delaware or, to the knowledge of such counsel without independent investigation, any other agreement or instrument to which the Company or any stockholder is a party;

     (iv) Registration Rights. To the knowledge of such counsel, other than as described in Schedule E to this Agreement, there are no contracts, agreements or understandings between the Company and any person granting such person registration rights, and any person to whom the Company has granted registration rights has agreed not to or is not entitled to exercise such rights until after the expiration of the Lock-Up Period;

     (v) 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, will not be an “investment company” as defined in the

Investment Company Act;

     (vi) Absence of Further Requirements. No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority of the United States of America or the States of Texas, New York or Delaware is required for the consummation of the transactions contemplated by this Agreement in connection with the offering, issuance and sale of the Offered Securities by the Company, except such as have been obtained or made and such as may be required under state securities laws;

     (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 compliance with the terms and provisions hereof (a) will not conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, any agreement filed or incorporated by reference as an exhibit to the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2008, as amended, or the Registration Statement; (b) will not result in any violation of the provisions of the certificate of incorporation, by-laws, certificate of formation or limited liability company agreement (as applicable) of the Company or any of its subsidiaries or (c) will not result in any violation of any order, rule or regulation known to such counsel of any court or governmental agency or body under the federal laws of the United States of America, the General Corporation Law of the State of Delaware and the Delaware LLC Act, in each case having jurisdiction over the Company or its subsidiaries or any of their properties or assets, except with respect to clauses (a) and (c), as would not reasonably be expected to have a Material Adverse Effect;

     (viii) Power and Authority. The Company has full corporate or limited liability company power and authority to enter into this Agreement and to issue and sell the Offered Securities;

     (ix) Compliance with Registration Requirements; Effectiveness. The Registration Statement is an “automatic shelf registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date of the Agreement, the Final Prospectus was filed with the Commission pursuant to the subparagraph of Rule 424(b) specified in such opinion on the date specified therein, and, to the knowledge of such counsel, no stop order suspending the effectiveness of the Registration Statement or any part thereof has been issued and no notice of objection of the Commission to the use of such registration statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company and no proceeding for that purpose or pursuant to Section 8A of the Act against the Company or in connection with the offering is pending or threatened by the Commission;

     (x) Accurate Disclosure. Insofar as it relates to matters of law or legal conclusions, the discussion in the Preliminary Prospectus and the Final Prospectus under the heading “Certain U.S. Federal Income and Estate Tax Considerations,” is accurate in all material respects as of the date hereof and the statements in the General Disclosure Package, insofar as they purport to constitute a summary of the terms of the Offered Securities, fairly summarize in all material respects the portions of the documents addressed thereby;

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

     (xii) Compliance as to Form. The documents incorporated by reference in the Registration Statement, the General Disclosure Package and the Final Prospectus or any further amendment or supplement thereto made by the Company prior to such Closing Date (other than the financial statements and related schedules therein (including the notes thereto and the auditors’ reports thereon), the financial, statistical and reserve information therein, and exhibits thereto, as to which such counsel need not express an opinion), when they were filed with the Commission,

appeared on their face to have complied as to form in all material respects with the requirements of the Exchange Act and the rules and regulations of the Commission thereunder;

     (xiii) Regulation T, U and X. Neither the issuance, sale and delivery of the Offered Securities nor the application of the proceeds thereof by the Company as described in the Final Prospectus will 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.

     Such counsel shall also state that such counsel has participated in conferences with officers and other representatives of the Company, representatives of the independent public accountants of the Company and your representatives at which the contents of the Registration Statement, the General Disclosure Package and the Final Prospectus and any amendment and supplement thereto and related matters were discussed and, although such counsel has not independently verified, is not passing upon and does not assume responsibility for the accuracy, completeness or fairness of the Registration Statement, the General Disclosure Package, the Final Prospectus and any amendment or supplement thereto (except as expressly provided in paragraph x above), on the basis of the foregoing, no facts have come to the attention of such counsel to cause such counsel to believe that the (i) Registration Statement, at the time of its effective date (including the information, if any, deemed pursuant to Rule 430A, 430B or 430C to be part of the Registration Statement at the time of effectiveness), contained any 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, (ii) the General Disclosure Package, at the Applicable Time, 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, or (iii) the Final Prospectus or any amendment or supplement thereto as of their date and the Closing Date contains any 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, except that such counsel need not express an opinion with respect to the financial statements and related schedules (including the notes thereto and the auditors’ reports thereon), financial, reserve and statistical information contained in or omitted from the Final Prospectus or the Preliminary Prospectus.

     In rendering such opinion, such counsel may (A) rely in respect of matters of fact upon certificates of officers and employees of the Company and its subsidiaries and upon information obtained from public officials, (B) assume that all documents submitted to them as originals are authentic, that all copies submitted to them conform to the originals thereof, and that the signatures on all documents examined by them are genuine, (C) with respect to opinions as to the due qualification or registration of the Company and its subsidiaries, state that such opinions are solely based upon certificates of foreign qualification or registration provided by the Secretary of State of the applicable state, (D) state that they express no opinion with respect to any permits to own or operate any real or personal property, (E) state that they express no opinion with respect to the title of the Company or any subsidiary to any of their respective real or personal property nor with respect to the accuracy or descriptions of real or personal property, and (F) state that they express no opinion with respect to state or local taxes or tax statutes to which the Company or any subsidiary may be subject.

     In rendering such opinion, such counsel may state that its opinion is limited to matters governed by the federal laws of the United States of America, the laws of the State of New York, the General Corporation Law of the State of Delaware and the Delaware LLC Act and that such counsel is not admitted in the State of Delaware.

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

SCHEDULE E
REGISTRATION RIGHTS AGREEMENTS

1. Exchange and Registration Rights Agreement, dated as of April 24, 2006, among Mariner Energy, Inc., the guarantors party thereto and the initial purchasers party thereto.

2. Registration Rights Agreement among Mariner Energy, Inc. and each of the investors identified therein, dated March 11, 2005.