Underwriting Agreement

EXECUTION COPY

J.P. MORGAN SECURITIES INC.

UNDERWRITING AGREEMENT

PETROQUEST ENERGY, INC.

1,300,000 Shares of Series B Preferred Stock

Underwriting Agreement

September 19, 2007

J.P. Morgan Securities Inc.
 As Representative of the
 several Underwriters listed
 in Schedule 1 hereto
277 Park Avenue
New York, New York 10172

Ladies and Gentlemen:

          PetroQuest Energy, Inc., a Delaware corporation (the “Company”), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representative (the “Representative”), an aggregate of 1,300,000 shares of 6.875% Series B cumulative convertible perpetual preferred stock (the “Series B Preferred Stock”), par value $0.001 per share, of the Company (the “Underwritten Shares”) and, at the option of the Underwriters, up to an additional 195,000 shares of Series B Preferred Stock of the Company (the “Option Shares”). The Underwritten Shares and the Option Shares are herein referred to as the “Shares”. The shares of Series B Preferred Stock to be outstanding after giving effect to the sale of the Shares are herein referred to as the “Stock”. The Shares will be convertible into shares (the “Underlying Securities”) of common stock of the Company, par value $0.001 per share (the “Common Stock”). The terms of the Shares will be set forth in a certificate of designations to be filed with the Secretary of State of the State of Delaware on or prior to the Closing Date (as hereinafter defined).

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

          1. Registration Statement. The Company meets the requirements for use of Form S-3 under the Securities Act of 1933, as amended, and the rules and regulations of the Securities and Exchange Commission (the “Commission”) thereunder (collectively, the “Securities Act”), and has prepared and filed with the Commission a registration statement (File

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No. 333-131955) on Form S-3 including a prospectus (the “Basic Prospectus”), relating to securities to be issued from time to time by the Company, including the Shares and the Underlying Securities. Such registration statement, as amended at the time it was declared effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement”; and as used herein, the term “Preliminary Prospectus” means the Basic Prospectus included in the Registration Statement at the time of its effectiveness, together with the preliminary prospectus supplement dated September 19, 2007 filed with the Commission that omits Rule 430 Information, and the term “Final Prospectus” means the Basic Prospectus together with the final prospectus supplement in accordance with Rules 415 and 424(b) in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Shares. If the Company has filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement. Any reference in this Agreement to the Registration Statement, the Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of the Preliminary Prospectus or the Final Prospectus, as the case may be, and any reference to “amend”, “amendment” or “supplement” with respect to the Registration Statement, Preliminary Prospectus or the Final Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”), that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Final Prospectus.

          At or prior to the time when sales of the Shares were first made (the “Time of Sale”), the Company had prepared the following information (collectively with the pricing information set forth on Annex B, the “Time of Sale Information”): the Preliminary Prospectus dated September 19, 2007, and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act), if any, listed on Annex B hereto.

          2. Purchase of the Shares by the Underwriters. (a) The Company agrees to issue and sell the Underwritten Shares to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective number of Underwritten Shares set forth opposite such Underwriter’s name in Schedule 1 hereto at a price per share (the “Purchase Price”) of $47.50. The public offering price of the Shares is not in excess of the price recommended by Johnson Rice & Company, acting as a “qualified independent underwriter” within the meaning of Rule 2720 of the Rules of Conduct of the National Association of Securities Dealers, Inc.

          In addition, the Company agrees to issue and sell the Option Shares solely to cover over-allotment shares to the several Underwriters as provided in this Agreement, and the Underwriters, on the basis of the representations, warranties and agreements set forth herein and

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subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from the Company the Option Shares at the Purchase Price.

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

          The Underwriters may exercise the option to purchase the Option Shares at any time in whole or in part (but not more than once), on or before the thirtieth day following the date of this Agreement, by written notice from the Representative to the Company. Such notice shall set forth the aggregate number of Option Shares as to which the option is being exercised and the date and time when the Option Shares are to be delivered and paid for which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date nor later than the tenth full business day (as hereinafter defined) after the date of such notice (unless such time and date are postponed in accordance with the provisions of Section 10 hereof). Any such notice shall be given at least two business days prior to the date and time of delivery specified therein.

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

          (c) Payment for the Shares shall be made by wire transfer in immediately available funds to the account specified by the Company to the Representative in the case of the Underwritten Shares, at the offices of Cravath, Swaine & Moore LLP, 825 Eighth Avenue, New York, New York at 10:00 A.M. New York City time on September 25, 2007, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representative and the Company may agree upon in writing or, in the case of the Option Shares, on the date and at the time and place specified by the Representative in the written notice of the Underwriters’ election to purchase such Option Shares. The time and date of such payment for the Underwritten Shares is referred to herein as the “Closing Date” and the time and date for such payment for the Option Shares, if other than the Closing Date, is herein referred to as the “Additional Closing Date”.

          Payment for the Shares to be purchased on the Closing Date or the Additional Closing Date, as the case may be, shall be made against delivery to the Representative for the respective accounts of the several Underwriters of the Shares to be purchased on such date through the facilities of The Depository Trust Company (the “DTC”) in book-entry form registered in such names and in such denominations as the Representative shall request in writing not later than two

 

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full business days prior to the Closing Date or the Additional Closing Date, as the case may be, with any transfer taxes payable in connection with the sale of the Shares duly paid by the Company.

          (d) The Company acknowledges and agrees that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of Shares contemplated hereby (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person. Additionally, neither the Representative nor any other Underwriter is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company shall consult with its own advisors concerning such matters and shall be responsible for making its own independent investigation and appraisal of the transactions contemplated hereby, and the Underwriters shall have no responsibility or liability to the Company with respect thereto. Any review by the Underwriters of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Underwriters and shall not be on behalf of the Company.

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

(a) Preliminary Prospectus. No order preventing or suspending the use of the Preliminary Prospectus has been issued by the Commission, and the Preliminary Prospectus, as of its date, complied in all material respects with the Securities Act and did not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in the Preliminary Prospectus.

(b) Time of Sale Information. The Time of Sale Information, at the Time of Sale did not, and at the Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in such Time of Sale Information. No statement of material fact included in the Time of Sale Information that is required to be included in the Final Prospectus has been omitted therefrom.

(c) Issuer Free Writing Prospectus. Other than the Preliminary Prospectus and the Final Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not made, used, prepared, authorized, approved or referred to and will not prepare, make, use, authorize, approve or refer to any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Shares (each such communication by the Company or its agents and

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representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rules 134 and 168 under the Securities Act or (ii) the documents listed on Annex B hereto and other written communications approved in writing in advance by the Representative. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act has been filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with the Preliminary Prospectus filed prior to the first use of such Issuer Free Writing Prospectus, did not, and at the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in any Issuer Free Writing Prospectus.

(d) Registration Statement and Final Prospectus. The Registration Statement has been declared effective by the Commission. No order suspending the effectiveness of the Registration Statement has been issued by the Commission and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering has been initiated or, to the knowledge of the Company, threatened by the Commission; as of the applicable effective date of the Registration Statement and any amendment thereto, the Registration Statement complied and will comply in all material respects with the Securities Act, and did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading; and as of the date of the Final Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Final Prospectus will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided that the Company makes no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in the Registration Statement and the Final Prospectus and any amendment or supplement thereto.

(e) Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Final Prospectus or the Time of Sale Information, when they became effective or were filed with the Commission, as the case may be, conformed in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and none of such documents 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, in the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the Registration Statement, the Final Prospectus or the Time of Sale Information, when such documents become effective or are filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and will not contain any untrue statement of a material fact or

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omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(f) Financial Statements. The financial statements included, or incorporated by reference, in the Registration Statement, the Time of Sale Information and the Final Prospectus 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, except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, such financial statements have been prepared in conformity with the generally accepted accounting principles in the United States applied on a consistent basis and the supporting schedules included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Final Prospectus present fairly in all material respects the information required to be stated therein; and the other financial information included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Final Prospectus has been derived from the accounting records of the Company and its subsidiaries and presents fairly in all material respects the information shown thereby (except as otherwise stated therein).

(g) No Material Adverse Change. Except as disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, since the date of the latest audited financial statements included in the Registration Statement, the Time of Sale Information and the Final Prospectus there has not been any change in the capital stock or long-term debt of the Company or any of its subsidiaries, nor material adverse change, nor any development or event involving a prospective material adverse change, in the condition (financial or other), business, properties or results of operations of the Company and its subsidiaries taken as a whole, and, except as disclosed in or contemplated by the Registration Statement, the Time of Sale Information and the Final Prospectus, there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock other than dividends or distributions deemed to occur upon the exercise or exchange of stock options, warrants, or other convertible securities of such capital stock represents a portion of the exercise or exchange price thereof or made in lieu of withholding taxes in connection with any such exercise or exchange.

          (h) Organization and Good Standing. The Company and each of its subsidiaries has been duly incorporated or organized and is an existing corporation or limited liability company in good standing under the laws of the jurisdiction of its incorporation or organization, with power and authority (corporate and other) to own its properties and conduct its business as described in the Registration Statement, the Time of Sale Information and the Final Prospectus, except where the failure to have such power or authority would not individually or in the aggregate have a material adverse effect on the condition (financial or other), business, properties or results of operations of the Company and its subsidiaries taken as a whole (“Material Adverse Effect”); and the Company and each of its subsidiaries is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification, except where the failure to so qualify or to be in good standing would not result in a Material Adverse Effect.

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

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

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

          (l) The Underlying Securities. Upon issuance and delivery of the Shares in accordance with the Agreement, the Shares will be convertible at the option of the holder thereof into shares of the Underlying Securities in accordance with the terms of Shares; the Underlying Securities reserved for issuance upon conversion of the Shares have been duly authorized and reserved and, when issued upon conversion of the Shares in accordance with the terms of the Shares, will be validly issued, fully paid and non-assessable, and the issuance of the Underlying Securities will not be subject to any preemptive or similar rights.

          (m) No Violation or Default. Neither the Company nor any of its subsidiaries is in violation of its respective charter or by-laws (or other comparable organizational documents) or in default in the performance of any obligation, agreement, covenant or condition contained in any indenture, loan agreement, mortgage, 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 or their respective property is bound, the effect of which would have a Material Adverse Effect

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(n) No Conflicts. The execution, delivery and performance of this Agreement and the issuance and sale of the Shares and the Underlying Securities and compliance with the terms and provisions thereof will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, any statute, any rule, regulation or order of any governmental agency or body or any court having jurisdiction over the Company or any subsidiary of the Company or any of their properties, or any agreement or instrument to which the Company or any such subsidiary is a party or by which the Company or any such subsidiary is bound, other than the Second Amended and Restated Credit Agreement dated November 18, 2005, as amended, among the Company, its subsidiaries and lenders party thereto, or to which any of the properties of the Company or any such subsidiary is subject the effect of which would have a Material Adverse Effect, or the charter or by-laws (or other comparable organizational documents) of the Company or any such subsidiary, and the Company has full power and authority to authorize, issue and sell the Shares and Underlying Securities as contemplated by this Agreement.

(o) No Consents Required. No consent, approval, authorization, or order of, or filing with, any governmental agency or body or any court is required for the consummation of the transactions contemplated by this Agreement in connection with the issuance and sale of the Shares by the Company, except for registration or qualification of the Shares under applicable securities or “Blue Sky” laws of the various states, as may be required by the New York Stock Exchange (the “Exchange”) and such as have already been obtained.

(p) Legal Proceedings. Except as disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, there are no pending legal, governmental or regulatory investigations, actions, suits or proceedings against or affecting the Company, any of its subsidiaries or any of their respective properties that, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement; and no such legal, governmental or regulatory investigations, actions, suits or proceedings are, to the Company’s knowledge, threatened or contemplated; and (i) there are no current or pending legal, governmental or regulatory actions, suits or proceedings that are required under the Securities Act to be described in the Registration Statement that are not so described in the Registration Statement, the Time of Sale Information and the Final Prospectus and (ii) there are no statutes, regulations or contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement or described in the Registration Statement or the Final Prospectus that are not so filed as exhibits to the Registration Statement or described in the Registration Statement, the Time of Sale Information and the Final Prospectus.

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

(r) Title to Real and Personal Property. Except as disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, the Company and its subsidiaries have

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good and marketable title to all real properties and all other properties and assets owned by them, in each case free from liens, encumbrances and defects that would materially affect the value thereof or materially interfere with the use made or to be made thereof by them; and except as disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, the Company and its subsidiaries hold any leased real or personal property under valid and enforceable leases with no exceptions that would materially interfere with the use made or to be made thereof by them.

          (s) Title to Intellectual Property. The Company and its subsidiaries own, possess or can acquire on reasonable terms, adequate trademarks, trade names and other rights to inventions, know-how, patents, copyrights, confidential information and other intellectual property (collectively, “intellectual property rights”) necessary to conduct the business now operated by them, or presently employed by them, and have not received any notice of infringement of or conflict with asserted rights of others with respect to any intellectual property rights that, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect.

          (t) No Undisclosed Relationships. No relationship, direct or indirect, exists between or among the Company or any of its subsidiaries, on the one hand, and the directors, officers, stockholders, customers or suppliers of the Company or any of its subsidiaries, on the other, that is required by the Securities Act to be described in the Registration Statement and the Final Prospectus and that is not so described in such documents and in the Time of Sale Information.

          (u) Investment Company Act. The Company is not an open-end investment company, unit investment trust or face-amount certificate company that is or is required to be registered under Section 8 of the United States Investment Company Act of 1940 (the “Investment Company Act”); and the Company is not and, after giving effect to the offering and sale of the Shares and the application of the proceeds thereof as described in the Registration Statement, the Time of Sale Information and the Final Prospectus, will not be an “investment company” as defined in the Investment Company Act.

          (v) Taxes. The Company and its subsidiaries have paid all material federal, state, local and foreign taxes except as may be contested in good faith and by appropriate proceedings and filed or have properly requested extensions of all tax returns required to be filed through the date hereof; and except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, there is no tax deficiency that has been, or could reasonably be expected to be, asserted against the Company or any of its subsidiaries or any of their respective properties or assets and that would have a Material Adverse Effect.

          (w) Licenses and Permits. The Company and its subsidiaries possess adequate certificates, authorities or permits issued by appropriate governmental agencies or bodies necessary to conduct the business now operated by them and have not received any notice of proceedings relating to the revocation or modification of any such certificate, authority or permit that, if determined adversely to the Company or any of its subsidiaries, would have a Material Adverse Effect.

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          (x) No Labor Disputes. No labor dispute with the employees of the Company or any subsidiary exists or, to the knowledge of the Company, is imminent that might have a Material Adverse Effect.

(y) Compliance With Environmental Laws. Except as disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, neither the Company nor any of its subsidiaries is in violation of any statute, any rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “environmental laws”), owns or operates any real property contaminated with any substance that is subject to any environmental laws, is liable for any off-site disposal or contamination pursuant to any environmental laws, or is subject to any claim relating to any environmental laws, which violation, contamination, liability or claim would individually or in the aggregate have a Material Adverse Effect; and the Company are not aware of any pending investigation which might lead to such a claim.

(z) Compliance With ERISA. Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company or any of its affiliates for employees or former employees of the Company and its affiliates has been maintained in compliance in all material respects with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Internal Revenue Code of 1986, as amended (the “Code”); no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any such plan excluding transactions effected pursuant to a statutory or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “accumulated funding deficiency” as defined in Section 412 of the Code has been incurred, whether or not waived, and the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued under such plan determined using reasonable actuarial assumptions.

(aa) Disclosure Controls. The Company maintains disclosure controls and procedures (as defined in Rule 13a-15(e) of the Exchange Act) designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported in accordance with the Exchange Act and the rules and regulations thereunder. The Company has carried out evaluations, under the supervision and with the participation of the Company’s management, of the effectiveness of the design and operation of the Company’s disclosure controls and procedures in accordance with Rule 13a-15 of the Exchange Act.

          (bb) Accounting Controls. The Company and its subsidiaries maintain systems of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply in all material respects with the requirements of the Exchange Act and have been designed by, or under the supervision of, their respective principal executive and principal financial officers, or persons performing similar functions, to provide reasonable assurance regarding the reliability of

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financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles in the United States, including, but not limited to internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles in the United States and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as disclosed in the Registration Statement, the Time of Sale Information and the Final Prospectus, there are no material weaknesses in the Company’s internal controls.

          (cc) Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, including business interruption insurance, which insurance is in amounts and insures against such losses and risks as are adequate to protect the Company and its subsidiaries and their respective businesses and are customary for the businesses in which they are engaged; and neither the Company nor any of its subsidiaries has (i) received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance or (ii) any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business.

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

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

          (ff) Compliance with OFAC. None of the Company, any of its subsidiaries or, to the knowledge of the Company, any director, officer, agent, employee or Affiliate of the Company or any of its subsidiaries is currently subject to any U.S. sanctions administered by the Office of

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Foreign Assets Control of the U.S. Department of the Treasury (“OFAC”); and the Company will not directly or indirectly use the proceeds of the offering of the Shares hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiary, joint venture partner or other person or entity, for the purpose of financing the activities of any person currently subject to any U.S. sanctions administered by OFAC.

          (gg) No Restrictions on Subsidiaries. The entities listed on Schedule 2 hereto are the only subsidiaries, direct or indirect, of the Company; and except as disclosed in the Registration Statement, the Time of Sale Information or the Final Prospectus, 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.

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

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

          (kk) Margin Rules. Neither the Company nor any of its subsidiaries nor any agent thereof acting on the behalf of them has taken, and none of them will take, any action that might cause this Agreement or the issuance or sale of the Shares to violate Regulation T, Regulation U or Regulation X of the Board of Governors of the Federal Reserve System.

          (ll) Forward-Looking Statements. No forward-looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) contained in the Registration Statement, the Time of Sale Information and the Final Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

          (mm) Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included in the Registration Statement, the Time of Sale Information and the Final Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

          (nn) Sarbanes-Oxley Act. There is and has been no failure on the part of the Company or any of the Company’s directors or officers, in their capacities as such, to comply in all material respects with any provision of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated in connection therewith (the “Sarbanes-Oxley Act”), including Section 402 related to loans and Sections 302 and 906 related to certifications.

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          (oo) Status under the Securities Act. The Company is not an ineligible issuer as defined under the Securities Act, in each case at the times specified in the Securities Act in connection with the offering of the Shares.

          (pp) DTC. The Company will assist the Representative in arranging for the Securities to be eligible for clearance and settlement through the DTC.

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

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

          (b) Delivery of Copies. The Company will deliver, without charge, (i) to the Representative, two copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and documents incorporated by reference therein; and (ii) to each Underwriter (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto (without exhibits) and (B) during the Prospectus Delivery Period (as defined below), as many copies of the Final Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein) and the Issuer Free Writing Prospectus as the Representative may reasonably request; provided that the availability of the Registration Statement and each amendment thereto on EDGAR shall constitute delivery so long as the EDGAR copy is substantially identical except as permitted by Regulation S-T. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Shares as in the reasonable opinion of counsel for the Underwriters a prospectus relating to the Shares is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Shares by any Underwriter or dealer.

          (c) Amendments or Supplements, Issuer Free Writing Prospectuses. Before preparing, using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement or the Final Prospectus, whether before or after the time that the Registration Statement becomes effective, the Company will furnish to the Representative and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not prepare, use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus

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or file any such proposed amendment or supplement to which the Representative reasonably objects.

          (d) Notice to the Representative. The Company will advise the Representative promptly, and confirm such advice in writing, (i) during the Prospectus Delivery Period when any amendment to the Registration Statement has been filed or becomes effective; (ii) when any supplement to the Final Prospectus or any Issuer Free Writing Prospectus or any amendment to the Final Prospectus has been filed; (iii) during the Prospectus Delivery Period of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Final Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (iv) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of the Preliminary Prospectus or the Final Prospectus or the initiation or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (v) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Final Prospectus, the Time of Sale Information or any Issuer Free Writing Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein, in the light of the circumstances existing when the Final Prospectus, the Time of Sale Information or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; (vi) during the Prospectus Delivery Period of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act; and (vii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Shares for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and the Company will use its commercially reasonable efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus or the Final Prospectus or suspending any such qualification of the Shares and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

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

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make the statements therein, in the light of the circumstances, not misleading or (ii) it is necessary to amend or supplement the Time of Sale Information to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representative may designate, such amendments or supplements to the Time of Sale Information as may be necessary so that the statements in the Time of Sale Information as so amended or supplemented will not, in the light of the circumstances, be misleading or so that the Time of Sale Information will comply with law.

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

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

          (h) Clear Market. For a period of 60 days after the date of the initial public offering of the Shares, the Company will not (i) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise, without the prior written consent of the Representative, other than the Shares to be sold hereunder and any shares of Common Stock of the Company or any Securities convertible or exchangeable into Common Stock (i) issued pursuant to existing equity incentive plans or issued upon the exercise of incentive awards granted under existing equity incentive plans or (ii) issued in connection with acquisitions of the Company, provided that the aggregate market value of all such shares issued in connection with this clause (ii) does not exceed 5% of the market capitalization of the Company as of 4:30 pm (New York City time) on the Closing Date and the recipients agree in writing to be bound by restrictions contained in the “lock-up” agreements, each substantially in the form of Exhibit A hereto. Notwithstanding the foregoing, if (1) during the last 17 days of the 60-day restricted period, the Company issues an earnings release or material news or a material event relating to the Company occurs; or (2) prior to the expiration of the 60-day restricted period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the 60-day period, the restrictions imposed by this Agreement shall continue to apply until the

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expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event, except that such extension will not apply if (A) at the end of the 60-day restricted period, the shares of Common Stock are “actively traded securities” (as defined in Regulation M) and (B) the Company meets the applicable requirements of paragraph (a)(1)(d) Rule 139 under the Securities Act.

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

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

          (k) Underlying Securities. The Company will reserve and keep available at all times, free of pre-emptive rights, shares of Common Stock for the purpose of enabling the Company to satisfy all obligations to issue the Underlying Securities upon conversion of the Shares. The Company will use its best efforts to list the Underlying Securities on the Exchange.

          (l) Reports. So long as the Shares are outstanding, the Company will furnish to the Representative, as soon as they are available, copies of all reports or other communications (financial or other) furnished to holders of the Shares, and copies of any reports and financial statements furnished to or filed with the Commission or any national securities exchange or automatic quotation system; provided that the availability of the Registration Statement and each amendment thereto on EDGAR shall constitute delivery so long as the EDGAR copy is substantially identical except as permitted by Regulation S-T.

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

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

          (a) It has not and will not use, authorize use of, refer to, or participate in the planning for use of, any “free writing prospectus”, as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that solely as a result of such use by such Underwriter would not trigger an obligation to file such free writing prospectus with the commission pursuant to Rule 433, (ii) any Issuer Free Writing Prospectus listed on Annex B or prepared pursuant to Section 3(c) or Section 4(c) above, or (iii) any free writing prospectus prepared by such Underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”).

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          (b) It has not and will not distribute any Underwriter Free Writing Prospectus referred to in clause (a)(i) in a manner reasonably designed to lead to its broad unrestricted dissemination.

          (c) It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Shares unless such terms have previously been included in a free writing prospectus filed with the Commission; provided that Underwriters may use a term sheet substantially in the form of Annex C hereto without the consent of the Company; provided further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet.

          (d) It will, pursuant to reasonable procedures developed in good faith, retain copies of each free writing prospectus used or referred to by it, in accordance with Rule 433 under the Securities Act.

          (e) It is not subject to any pending proceeding under Section 8A of the Securities Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated during the Prospectus Delivery Period).

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

          (a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose, pursuant to Rule 401(g)(2) or pursuant to Section 8A under the Securities Act shall be pending before or threatened by the Commission; the Prospectus and the Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Representative.

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

          (c) No Downgrade. Subsequent to the execution and delivery of this Agreement, (i) no downgrading shall have occurred in the rating accorded any securities or preferred stock of or guaranteed by the Company or any of its subsidiaries by any “nationally recognized statistical rating organization”, as such term is defined by the Commission for purposes of Rule 436(g)(2) under the Securities Act and (ii) no such organization shall have publicly announced that it has

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under surveillance or review, or has changed its outlook with respect to, its rating of any securities or preferred stock of or guaranteed by the Company or any of its subsidiaries (other than an announcement with positive implications of a possible upgrading).

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

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

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

          (g) Opinion of Counsel for the Company. Porter & Hedges, L.L.P., counsel for the Company, Pray Walker Jackman Williamson & Marlar, P.C., special Oklahoma counsel for the company and Daniel G. Fournerat, general counsel of the Company shall have furnished to the Representative, at the request of the Company, their written opinion or opinions, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representative, to the effect set forth in Annex A hereto.

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          (h) Opinion of Counsel for the Underwriters. The Representative shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion of Cravath, Swaine & Moore LLP, counsel for the Underwriters, with respect to such matters as the Representative may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

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

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

          (k) Exchange Listing. An application for the listing of the Underlying Securities shall have been submitted to the Exchange.

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

          (m) DTC. The Securities shall be eligible for clearance and settlement through DTC.

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

          All opinions, letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

          7. Indemnification and Contribution.

          (a) Indemnification of the Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, directors and officers and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, legal fees and other expenses incurred in connection with any suit,

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action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, (ii) or any untrue statement or alleged untrue statement of a material fact contained in the Final Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information (including any Time of Sale Information that has subsequently been amended), or caused by any omission or alleged omission to state therein a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (b) below.

          The Company also agrees to indemnify and hold harmless, Johnson Rice & Company L.L.C., its affiliates, directors and officers and each person, if any, who controls Johnson Rice & Company L.L.C. within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities incurred as a result of Johnson Rice & Company L.L.C.’s participation as a “qualified independent underwriter” within the meaning of the Rules of Conduct of the National Association of Securities Dealers, Inc. in connection with the offering of the Shares; provided, however, that the company shall not be liable in any such case to the extent that such losses, claims, damages or liabilities results from the gross negligence or willful misconduct of Johnson Rice & Company L.L.C.

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

          (c) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against

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any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “Indemnified Person”) shall promptly notify the person against whom such indemnification may be sought (the “Indemnifying Person”) in writing; provided that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under this Section 7 except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under this Section 7. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person (who shall not, without the consent of the Indemnified Person, be counsel to the Indemnifying Person) to represent the Indemnified Person in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary or (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceeding in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be paid or reimbursed as they are incurred ; provided, however that if indemnity may be sought pursuant to the second paragraph of Section 7(a) above in respect of such proceeding, then in addition to such separate firm of the Underwriters, their affiliates and such control persons of the Underwriters the indemnifying party shall be liable for the fees and expenses of not more than one separate firm (in addition to any local counsel) for Johnson Rice & Company in its capacity as a “qualified independent underwriter”, its affiliates and all persons, if any, who control Johnson Rice & Company within the meaning of either Section 15 of the Securities Act or Section 20 of the Exchange Act. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by J.P. Morgan Securities Inc. and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such

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Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

          (d) Contribution. If the indemnification provided for in paragraphs (a) and (b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and the Underwriters or Johnson Rice & Company L.L.C. in its capacity as a “qualified independent underwriter”, as the case may be, on the other, from the offering of the Shares or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company, on the one hand, and the Underwriters or Johnson Rice & Company L.L.C. in its capacity as a “qualified independent underwriter”, as the case may be, on the other, in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company, on the one hand, and the Underwriters or Johnson Rice & Company L.L.C. in its capacity as a “qualified independent underwriter”, as the case may be, on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Shares and the total underwriting discounts and commissions received by the Underwriters in connection therewith, in each case as set forth in the table on the cover of the Final Prospectus, or the fee to be received by Johnson Rice & Company L.L.C. in its capacity as a “qualified independent underwriter”, as the case may be, bear to the aggregate offering price of the Shares. The relative fault of the Company, on the one hand, and the Underwriters or Johnson Rice & Company L.L.C. in its capacity as a “qualified independent underwriter”, as the case may be, on the other, shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters or Johnson Rice & Company L.L.C. in its capacity as a “qualified independent underwriter”, if any, as the case may be, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

          (e) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 7 were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (d) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (d) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of this Section 7, in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such

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Underwriter with respect to the offering of the Shares exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to this Section 7 are several in proportion to their respective purchase obligations hereunder and not joint.

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

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

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

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

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includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule 1 hereto that, pursuant to this Section 10, purchases Shares that a defaulting Underwriter agreed but failed to purchase.

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

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

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

          11. Payment of Expenses. (a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the authorization, issuance, sale, preparation and delivery of the Shares and any taxes payable in that connection; (ii) the costs incident to the preparation, printing and filing under the Securities Act of the Registration Statement, the Preliminary Prospectus, any Issuer Free Writing Prospectus, any Time of Sale Information and the Final Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the fees and expenses of the Company’s counsel and independent accountants; (iv) the fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Shares under the laws of such jurisdictions as the Representative may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related fees and expenses of counsel for the Underwriters); (v) the cost of preparing stock certificates; (vi) the costs and charges of any transfer agent and any registrar; (vii) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, the National Association of Securities Dealers, Inc.

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(including the fees and expenses of Johnson Rice & Company acting as “qualified independent underwriter” within the meaning of the aforementioned Rule 2720 of The Rules of Conduct; (viii) all expenses incurred by the Company in connection with any “road show” presentation to potential investors and (ix) all expenses and application fees incurred in connection with the application for the approval of the Securities for book-entry transfer by DTC.

          (b) If (i) this Agreement is terminated pursuant to Sections 9(ii), (ii) the Company for any reason fails to tender the Shares for delivery to the Underwriters or (iii) the Underwriters decline to purchase the Shares for any reason permitted under this Agreement (other than section 6(h) or any subsection of Section 6 where the failure to satisfy the applicable conditions was solely attributable to an Underwriter), the Company agrees to reimburse the Underwriters for all out-of-pocket costs and expenses (including the fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

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

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

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

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

          (b) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to the Representative c/o J.P. Morgan Securities Inc., 277 Park Avenue, New York, New York 10172 (fax: (212)  ###-###-####); Attention: Equity Syndicate Desk. Notices to the Company shall be given to it at 400

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East Kaliste Saloom Road, Suite 6000 , Lafayette, Louisiana 70508 (fax: (337)  ###-###-####); Attention: Daniel G. Fournerat, Executive Vice President and General Counsel.

          (c) Governing Law. This Agreement shall be governed by and construed in accordance with the laws of the State of New York.

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

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

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

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

Accepted: September     , 2007

J.P. MORGAN SECURITIES INC.

For itself and on behalf of the several Underwriters listed in Schedule 1 hereto.

By		/s/ Paul O’Hern                       Authorized Signatory

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Schedule 1

Underwriter		Number of Shares
J.P. Morgan Securities Inc.			910,000
Howard Weil Incorporated			156,000
Johnson Rice & Company L.L.C.			156,000
Coker & Palmer, Inc.			78,000
Total			1,300,000

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Schedule 2

Subsidiaries

PetroQuest Energy, L.L.C.

PetroQuest Oil & Gas, L.L.C.

Pittrans, Inc.

Sea Harvester Energy Development Co., L.L.C.

TDC Energy LLC