Exhibit 1.1

CONTINENTAL RESOURCES, INC.

(an Oklahoma corporation)

10,000,000 Shares of Common Stock

UNDERWRITING AGREEMENT

Dated: March 3, 2011

CONTINENTAL RESOURCES, INC.

(an Oklahoma corporation)

10,000,000 Shares of Common Stock

UNDERWRITING AGREEMENT

March 3, 2011

Merrill Lynch, Pierce, Fenner & Smith

    Incorporated

J.P. Morgan Securities LLC

as Representatives of the several Underwriters

listed in Schedule I hereto

c/o Merrill Lynch, Pierce, Fenner & Smith

    Incorporated

One Bryant Park

New York, New York 10036

J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Ladies and Gentlemen:

Continental Resources, Inc., an Oklahoma corporation (the “Company”), proposes to issue and sell to the several Underwriters listed in Schedule I hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), an aggregate of 9,170,000 shares (the “Company Underwritten Shares”) of common stock, par value of $0.01 per share, of the Company (the “Stock”), and the Harold G. Hamm Revocable Inter Vivos Trust, the Harold Hamm DST Trust and the Harold Hamm HJ Trust (each, a “Selling Shareholder” and together, the “Selling Shareholders”) propose to sell to the Underwriters an aggregate of 750,000, 48,000 and 32,000 shares of Stock, respectively (together, the “Selling Shareholder Shares”) and, at the option of the Underwriters, the Company proposes to issue and sell to the Underwriters up to an additional 1,500,000 shares of Stock (the “Option Shares”). The Company Underwritten Shares and the Option Shares are herein referred to as the “Company Shares.” The Company Underwritten Shares and the Selling Shareholder Shares are herein referred to as the “Underwritten Shares.” The Underwritten Shares and the Option Shares are herein referred to as the “Shares.”

Each representation, warranty, covenant, agreement, undertaking, acknowledgment and expressed understanding of the Harold G. Hamm Revocable Inter Vivos Trust in this Agreement shall be the joint and several representation, warranty, covenant, agreement, undertaking, acknowledgment and expressed understanding, as applicable, of the Harold G. Hamm Revocable Inter Vivos Trust (the “HGH Trust”) and Harold G. Hamm.

The Company and each of the Selling Shareholders, severally and not jointly, hereby confirm their agreement with the several Underwriters concerning the purchase and sale of the Shares, as follows:

1. Registration Statement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement on Form S-3 (File No. 333-168182) including a prospectus, relating to the Shares. Such registration statement, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement”; and as used herein, the term “Preliminary Prospectus” means each prospectus included in such registration statement (and any amendments thereto), any prospectus supplement relating to the Shares filed with the Commission pursuant to Rule 424(b) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the prospectus in the form first used (or made available upon the request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Shares. Any reference in this Agreement to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Prospectus, as the case may be, and any reference to “amend”, “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”) that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

At or prior to the Time of Sale (as defined below), the Company had prepared the following information (collectively with the pricing information set out on Annex A hereto, the “Time of Sale Information”): a Preliminary Prospectus dated March 1, 2011 and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Annex A hereto.

“Time of Sale” means 5:15 P.M., New York City time, on March 3, 2011.

2. Purchase of the Shares by the Underwriters. (a) The Company and each of the Selling Shareholders agree, severally and not jointly, to 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 at a purchase price per share of $65.45 (the “Purchase Price”) the number of Underwritten Shares set forth opposite such Underwriter’s name in Schedule I hereto.

In addition, the Company agrees to issue and sell the Option Shares to the several Underwriters as provided in this Agreement and the Underwriters, on the basis of the representations and warranties and agreements herein contained and subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from the Company the Option Shares at the Purchase Price less an amount per share equal to any dividends or distributions declared by the Company and payable on the Underwritten Shares but not payable on the Option Shares. If any Option Shares are to be purchased, the number of Option Shares to be purchased by each Underwriter shall be the number of Option Shares which bears the same ratio to the aggregate number of Option Shares being purchased as the number of Underwritten Shares set forth opposite the name of such Underwriter in Schedule I hereto (or such number increased as set forth in Section 12 hereof) bears to the aggregate number of Underwritten Shares purchased by the several Underwriters, subject, however, to such adjustments to eliminate any fractional Shares as the Representatives in their sole discretion shall make.

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The Underwriters may exercise the option to purchase the Option Shares at any time in whole, or from time to time in part, solely for the purpose of covering over-allotments made in connection with the offering of the Underwritten Shares, on or before the thirtieth day following the date of the Prospectus, by written notice from the Representatives to the Company. Such notice shall set forth the aggregate number of Option Shares as to which the option is being exercised and the date and time when the Option Shares are to be delivered and paid for which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date 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 12 hereof). Unless otherwise agreed by the Company, after the Closing Date, any such notice shall be given at least two business day prior to the date and time of delivery specified therein.

(b) The Company and the Selling Shareholders understand that the Underwriters intend to make a public offering of the Shares as soon after the effectiveness of this Agreement as in the judgment of the Representatives is advisable, and initially to offer the Shares on the terms set forth in the Prospectus. The Company and the Selling Shareholders acknowledge and agree 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 accounts specified to the Representatives by the Company, with respect to the Company Shares, and by each of the Selling Shareholders, with respect to the Selling Shareholder Shares, at the offices of Davis Polk & Wardwell LLP, 450 Lexington Avenue, New York, NY 10017 at 10:00 A.M. New York City time on March 9, 2011, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representatives, the Company and the Selling Shareholders may agree upon in writing or, in the case of the Option Shares, on the date and at the time and place specified by the Representatives in the written notice of the Underwriters’ election to purchase such Option Shares. The time and date of such payment for the Underwritten Shares is referred to herein as the “Closing Date” and the time and date for such payment for the Option Shares, if other than the Closing Date, is herein referred to as the “Additional Closing Date.”

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

(d) Each of the Company and the Selling Shareholders acknowledge and agree that the Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company and the Selling Shareholders 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, the Selling Shareholders or any other person. Additionally, neither the

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Representatives nor any other Underwriter is advising the Company, the Selling Shareholders or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company and the Selling Shareholders shall consult with their own advisors concerning such matters and shall be responsible for making their own independent investigation and appraisal of the transactions contemplated hereby, and the Underwriters shall have no responsibility or liability to the Company or the Selling Shareholders 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 or the Selling Shareholders.

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

(a) Preliminary Prospectus. No order preventing or suspending the use of any Preliminary Prospectus has been issued by the Commission, and each Preliminary Prospectus, at the time of filing thereof, 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 Representatives expressly for use in any Preliminary Prospectus.

(b) Time of Sale Information. The Time of Sale Information, at the Time of Sale 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 reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in such Time of Sale Information. No statement of material fact included in the Prospectus has been omitted from the Time of Sale Information and no statement of material fact included in the Time of Sale Information that is required to be included in the Prospectus has been omitted therefrom.

(c) Issuer Free Writing Prospectus. Other than the Registration Statement, the Preliminary Prospectus and the Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not 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 representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Annex A hereto, each electronic road show and any other written communications approved in writing in advance by the Representatives. Each such Issuer Free Writing Prospectus complied in all material respects with the Securities Act, has been or will be (within the time period specified in Rule 433) filed in accordance with the Securities Act (to the extent required thereby) and, when taken together with the Preliminary Prospectus accompanying, or delivered prior to delivery of, such Issuer Free Writing Prospectus, did not, and at the Closing Date and at 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

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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 Representatives expressly for use in any Issuer Free Writing Prospectus.

(d) Registration Statement and Prospectus. The Registration Statement is an “automatic shelf registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date hereof; and no notice of objection of the Commission to the use of such registration statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company. No order suspending the effectiveness of the Registration Statement has been issued by the Commission and no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Shares has been initiated or, to the knowledge of the Company, threatened by the Commission; as of the applicable effective date of the Registration Statement and any post-effective amendment thereto, the Registration Statement and any such post-effective amendment complied and will comply in all material respects with the Securities Act, and did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus will not contain any untrue statement of a material fact or omit to state a material fact 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 Representatives expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto.

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

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

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Statement, the Time of Sale Information and the Prospectus has been derived from the accounting records of the Company and its subsidiary and presents fairly in all material respects the information shown thereby; and the pro forma financial information and the related notes thereto included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus has been prepared in all material respects consistently with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and give effect to assumptions made on a reasonable basis as set forth in the Registration Statement, the Time of Sale Information and the Prospectus.

(g) No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus, except in each case as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, (i) there has not been any change in the capital stock, or material change in the long-term debt, of the Company or its subsidiary, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development involving a prospective material adverse change, in or affecting the business, properties, management, financial position, shareholders’ equity, results of operations or prospects of the Company and its subsidiary taken as a whole; (ii) neither the Company nor its subsidiary has entered into any transaction or agreement that is material to the Company and its subsidiary taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiary taken as a whole; and (iii) neither the Company nor its subsidiary has sustained any material loss or interference with its business from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority.

(h) Organization and Good Standing. Each of the Company and its subsidiary has been duly organized and is validly existing and in good standing under the laws of its jurisdiction of organization, is duly qualified to do business and is in good standing in each jurisdiction in which its ownership or lease of property or the conduct of its businesses requires such qualification, and has all power and authority necessary to own or hold its properties and to conduct the businesses in which it is engaged, except where the failure to be so qualified or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the business, properties, management, financial condition, shareholders’ equity, results of operations, cash flows or prospects of the Company and its subsidiary taken as a whole or on the transactions contemplated hereby (a “Material Adverse Effect”). The Company does not own or control, directly or indirectly, any corporation, association or other entity other than Banner Pipeline Company, L.L.C. (“Banner”), and Banner is the only subsidiary of the Company.

(i) Capitalization. The Company has an authorized capitalization as set forth in the Registration Statement, the Time of Sale Information and the Prospectus under the heading “Capitalization”; all the outstanding shares of capital stock of the Company (including the Selling Shareholder Shares) 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 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 its subsidiary, 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 Prospectus; and all the outstanding shares of capital stock or other

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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.

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

(l) The Shares. The Company 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 Registration Statement, the Time of Sale Information and the Prospectus; and the issuance of the Company Shares is not subject to any preemptive or similar rights.

(m) No Violation or Default. Neither the Company nor its subsidiary is (i) in violation of its charter or by-laws or similar organizational documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement, lease or other agreement or instrument to which the Company or its subsidiary is a party or by which the Company or its subsidiary is bound (including, without limitation, the Company’s Seventh Amended and Restated Credit Agreement among the Company, the lenders party thereto from time to time and Union Bank, N.A., as administrative agent, as issuing lender and as swing line lender, dated June 30, 2010, the Indenture dated as of September 23, 2009 among the Company, its subsidiary and Wilmington Trust FSB, as trustee, the Indenture dated as of April 5, 2010 among the Company, its subsidiary and Wilmington Trust FSB, as trustee and the Indenture dated as of September 16, 2010 among the Company, its subsidiary, and Wilmington Trust FSB, as trustee) or to which any of the property or assets of the Company or its subsidiary is subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (ii) and (iii) above, for any such default or violation that would not, individually or in the aggregate, have a Material Adverse Effect.

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

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(o) No Consents Required. No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of this Agreement, the issuance and sale of the Company Shares by the Company, the sale of the Selling Shareholder Shares by the Selling Shareholders and the consummation by the Company of the transactions contemplated hereby, except for the registration of the Shares under the Securities Act and such consents, approvals, authorizations, orders and registrations or qualifications as may be required by the Financial Industry Regulatory Authority, Inc. (“FINRA”) and under applicable state securities laws in connection with the purchase and distribution of the Shares by the Underwriters and any consent, approval, authorization, order, registration or qualification that either has been, or prior to the Closing Date will have been, obtained or made, or which if not obtained or made, would not, individually or in the aggregate, have a Material Adverse Effect.

(p) Legal Proceedings. Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, there are no legal, governmental or regulatory investigations, actions, suits or proceedings pending to which the Company or its subsidiary is or may be a party or to which any property of the Company or its subsidiary is or may be the subject that, individually or in the aggregate, if determined adversely to the Company or its subsidiary, could reasonably be expected to have a Material Adverse Effect or materially and adversely affect the ability of the Company to perform its obligations under this Agreement; to the knowledge of the Company, no such investigations, actions, suits or proceedings are threatened or contemplated by any governmental or regulatory authority or others; 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 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 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 Prospectus.

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

(r) Title to Real and Personal Property. The Company has good and marketable title to all real and other property owned by it, in each case free and clear of all liens, encumbrances and defects except those (i) described in the Registration Statement, the Time of Sale Information and the Prospectus or (ii) that would not, individually or in the aggregate, have a Material Adverse Effect. Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, each of the Company and its subsidiary holds all leased real and other property under valid and enforceable leases, with such exceptions as would not have a Material Adverse Effect.

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

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

(u) Taxes. The Company and its subsidiary have paid all federal, state, local and foreign taxes and filed all tax returns required to be paid or filed through the date hereof; and except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, or as would not, individually or in the aggregate, have a Material Adverse Effect, there is no tax deficiency that has been, or could reasonably be expected to be, asserted against the Company or its subsidiary or any of their respective properties or assets.

(v) Licenses and Permits. The Company and its subsidiary possess all licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in the Registration Statement, the Time of Sale Information and the Prospectus, except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect; and except as described in the Registration Statement, the Time of Sale Information and the Prospectus, or as would not, individually or in the aggregate, have a Material Adverse Effect, neither the Company nor its subsidiary has received notice of any revocation or modification of any such license, certificate, permit or authorization or has any reason to believe that any such license, certificate, permit or authorization will not be renewed in the ordinary course.

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

(x) Compliance With Environmental Laws. (i) The Company and its subsidiary (x) are in compliance with any and all applicable federal, state, local and foreign laws (including common law), rules, regulations, requirements, decisions and orders relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “Environmental Laws”); (y) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under applicable Environmental Laws (collectively “Environmental Permits”) to conduct their respective businesses; and (z) except as described in the Registration Statement, the Time of Sale Information and the Prospectus, have not received any notice or claim relating to Environmental Laws, including, without limitation, any notice or claim of any actual or potential liability for the investigation or remediation of any hazardous or toxic substances or wastes, pollutants or contaminants, and (ii) there are no costs or liabilities (whether accrued, contingent, absolute, determined, determinable or otherwise) associated with Environmental Laws or Environmental Permits, including, without limitation, any capital or operating expenditures required for cleanup, closure of properties or compliance with Environmental Laws or Environmental

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Permits, any related constraints on operating activities and any potential liabilities to third parties, of or relating to the Company or its subsidiary, except in the case of each of (i) and (ii) above, for any such failure to comply, or failure to receive required Environmental Permits, or cost or liability, as would not, individually or in the aggregate, have a Material Adverse Effect.

(y) 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 any transactions effected pursuant to a statutory or administrative exemption and transactions which, individually or in the aggregate, would not have a Material Adverse Effect; and no such plan is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA.

(z) Disclosure Controls. The Company and its subsidiary maintain an effective system of “disclosure controls and procedures” (as defined in Rule 13a-15(e) of the Exchange Act) that is designed to ensure that information required to be disclosed by the Company in reports that it files or submits under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including controls and procedures designed to provide reasonable assurance that such information is accumulated and communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure.

(aa) Accounting Controls. The Company and its subsidiary maintain a system of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of, the Company’s principal executive and principal financial officers, and effected by the Company’s board of directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, including those policies and procedures that (i) pertain to the maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets of the Company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance with authorizations of management and directors of the Company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the Company’s assets that could have a material effect on the Company’s financial statements. Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, there are no material weaknesses in the Company’s internal control over financial reporting.

(bb) Insurance. The Company and its subsidiary have insurance covering their respective properties, operations, personnel and businesses, which insurance is in amounts and insures against such losses and risks as the Company considers adequate to protect the Company and its subsidiary and their respective businesses and is reasonably customary for companies engaged in similar businesses in similar industries; and neither the Company nor its subsidiary 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 at reasonable cost from similar insurers as may be necessary to continue its business.

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(cc) No Restrictions on Subsidiary. 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.

(dd) No Broker’s Fees. Neither the Company nor its subsidiary 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 its subsidiary or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Shares.

(ee) No Registration Rights. Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, no person has the right to require the Company or its subsidiary to register any securities for sale under the Securities Act by reason of the filing of the Registration Statement with the Commission or the issuance and sale of the Company Shares to be sold by the Company hereunder or, to the knowledge of the Company, the sale of the Selling Shareholder Shares to be sold by the Selling Shareholders hereunder.

(ff) 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.

(gg) 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 Prospectus has been made or reaffirmed without a reasonable basis or has been disclosed other than in good faith.

(hh) 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 Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(ii) 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 with any applicable provision of the Sarbanes-Oxley Act of 2002 and any applicable rules and regulations promulgated in connection therewith, including Section 402 relating to loans and Sections 302 and 906 relating to certifications.

(jj) Reserve Data. (i) The oil and natural gas reserve estimates of the Company and its subsidiary as of December 31, 2008, 2009 and 2010 contained or incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus are derived from reports that have been prepared by, or have been audited by, Ryder Scott Company, LP, as set forth and to the extent indicated therein, and (ii) such estimates fairly reflect the oil and natural gas reserves of the Company and its subsidiary, as applicable, at the dates indicated therein and are in accordance, in all material respects, with Commission guidelines for each applicable year applied on a consistent basis throughout the years involved.

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(kk) Independent Petroleum Engineers. Ryder Scott Company, LP have represented to the Company that they are, and the Company believes them to be, independent petroleum engineers with respect to the Company and its subsidiary and for the periods set forth in the Registration Statement, the Time of Sale Information and the Prospectus.

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

(mm) Foreign Corrupt Practices Act. None of the Company, its subsidiary or, to the knowledge of the Company, any director, officer, agent, employee, affiliate or other person acting on behalf of the Company or its subsidiary is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA and the Company and, to the knowledge of the Company, its affiliates have conducted their businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

(nn) No Conflict with Money Laundering Laws. The operations of the Company and its subsidiary are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all applicable 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 its subsidiary with respect to the Money Laundering Laws is pending or, to the best knowledge of the Company, threatened.

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

4. Representations and Warranties of the Selling Shareholders. The Selling Shareholders, severally and not jointly, represent and warrant with respect to itself (and not with respect to any other Selling Shareholder) to each Underwriter and the Company that:

(a) Required Consents; Authority. All consents, approvals, authorizations and orders necessary for the execution and delivery by the Selling Shareholders of this Agreement, and for the sale

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and delivery of the Selling Shareholder Shares to be sold by the Selling Shareholders hereunder, have been obtained; and the Selling Shareholders have full right, power and authority to enter into this Agreement and to sell, assign, transfer and deliver the Selling Shareholder Shares to be sold by the Selling Shareholders hereunder; this Agreement has been duly executed and delivered by the Selling Shareholders. Harold G. Hamm is the sole trustee and beneficiary of the HGH Trust, controls the HGH Trust and has full power and authority to cause the HGH Trust to enter into this Agreement. Bert H. Mackie is a trustee of each of the Harold Hamm DST Trust and the Harold Hamm HJ Trust, controls the Harold Hamm DST Trust and the Harold Hamm HJ Trust and has full power and authority to cause the Harold Hamm DST Trust and the Harold Hamm HJ Trust to enter into this Agreement.

(b) Organization and Good Standing. Immediately prior to the closing of the purchase and sale of the Underwritten Shares on the Closing Date, the HGH Trust, the Harold Hamm DST Trust and the Harold Hamm HJ Trust will have good and valid title to 72.6%, 5.2% and 3.5%, respectively, of the issued and outstanding shares of Stock, and immediately after such purchase and sale (assuming no exercise of the Underwriters’ option to purchase the Option Shares), the HGH Trust, the Harold Hamm DST Trust and the Harold Hamm HJ Trust will have good and valid title to 68.5%, 4.9% and 3.3%, respectively, of the issued and outstanding shares of Stock.

(c) No Conflicts. The execution, delivery and performance by the Selling Shareholders of this Agreement, the sale of the Selling Shareholder Shares to be sold by the Selling Shareholders and the consummation by the Selling Shareholders of the transactions herein and therein contemplated will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any material property or assets of the Selling Shareholders pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Selling Shareholders are a party or by which the Selling Shareholders are bound or to which any of the property or assets of the Selling Shareholders are subject or (ii) result in the material violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory agency.

(d) Title to Shares. The Selling Shareholders have good and valid title to the Selling Shareholder Shares to be sold at the Closing Date by the Selling Shareholders hereunder, free and clear of all liens, encumbrances, equities or adverse claims; the Selling Shareholders will have, immediately prior to the Closing Date good and valid title to the Selling Shareholder Shares to be sold at the Closing Date by the Selling Shareholders, free and clear of all liens, encumbrances, equities or adverse claims; and, upon delivery of the certificates representing such Selling Shareholder Shares and payment therefor pursuant hereto, good and valid title to such Selling Shareholder Shares, free and clear of all liens, encumbrances, equities or adverse claims, will pass to the several Underwriters.

(e) No Stabilization. The Selling Shareholders have not taken and 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.

(f) Preliminary Prospectus. No Preliminary Prospectus, at the time of filing thereof, contained any untrue statement of a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) or omitted to state a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) which is 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.

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(g) Time of Sale Information. The Time of Sale Information, at the Time of Sale 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 concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) or omit to state a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) which is necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. No statement of material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) which is included in the Prospectus has been omitted from the Time of Sale Information and no statement of material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) which is included in the Time of Sale Information and which is required to be included in the Prospectus has been omitted therefrom.

(h) Issuer Free Writing Prospectus. Other than the Registration Statement, the Preliminary Prospectus and the Prospectus, the Selling Shareholders (including their agents and representatives, other than the Underwriters in their capacity as such) have not made, used, prepared, authorized, approved or referred to and will not prepare, make, use, authorize, approve or refer to any Issuer Free Writing Prospectus, other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Annex A hereto, each electronic road show and any other written communications approved in writing in advance by the Company and the Representatives.

(i) Registration Statement and Prospectus. As of the applicable effective date of the Registration Statement and any amendment thereto, the Registration Statement did not and will not contain any untrue statement of a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) or omit to state a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) which is required to be stated therein or necessary in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus will not contain any untrue statement of a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) or omit to state a material fact concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) which is 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.

(j) Material Information. As of the date hereof and as of the Closing Date, the sale of the Selling Shareholder Shares by the Selling Shareholders is not and will not be prompted by any material information concerning the Company which is not set forth in the Registration Statement, the Time of Sale Information or the Prospectus.

(k) Shares. The Selling Shareholders specifically agree that the obligations of the Selling Shareholders hereunder shall not be terminated by operation of law, whether by dissolution of the Selling Shareholders or the death or incapacity of Harold G. Hamm or any beneficiary or trustee of the Selling Shareholders or by the occurrence of any other event. If the Selling Shareholders shall be dissolved or Harold G. Hamm or any trustee or beneficiary of the Selling Shareholders should die or become incapacitated or if any other such event should occur before the delivery of the Selling Shareholder Shares hereunder, certificates representing such Selling Shareholder Shares shall be delivered by or on behalf of the Selling Shareholders in accordance with the terms and conditions of this Agreement, and actions taken pursuant thereto shall be as valid as if such dissolution, death, incapacity or other event had not occurred.

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

(a) Required Filings. The Company will file the final Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act, will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; will file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus until the expiration of the Prospectus Delivery Period; and will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, on the business day next succeeding the date of this Agreement in such quantities as the Representatives may reasonably request. The Company will pay the registration fee for this offering within the time period required by Rule 456(b)(1) under the Securities Act (without giving effect to the proviso therein) and in any event prior to the Closing Date.

(b) Delivery of Copies. The Company will deliver, without charge, (i) to the Representatives, three signed copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith; 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 Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein, except to the extent available on the Commission’s Electronic Data Gathering, Analysis, and Retrieval system (“EDGAR”), and each Issuer Free Writing Prospectus) as the Representatives may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Shares as in the opinion of counsel for the Underwriters a prospectus relating to the Shares is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Shares by any Underwriter or dealer.

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

(d) Notice to the Representatives. The Company will advise the Representatives promptly, and confirm such advice in writing, (i) when any amendment to the Registration Statement has been filed or becomes effective prior to the later of (A) the Closing Date or (B) the expiration of the Prospectus Delivery Period; (ii) when any supplement to the Prospectus or any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed; (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information prior to the later of (A) the Closing Date or (B) the expiration of the Prospectus Delivery Period; (iv) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus or the 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

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Period as a result of which the 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 Prospectus, the Time of Sale Information or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; (vi) 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 best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus or the Prospectus or suspending any such qualification of the Shares and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

(e) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state 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 Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with law, the Company will immediately notify the Underwriters thereof and forthwith prepare and, subject to subsection (c) above, file with the Commission and furnish to the Underwriters and to such dealers as the Representatives may designate, such amendments or supplements to the Prospectus as may be necessary so that the statements in the Prospectus as so amended or supplemented will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with law and (2) if at any time prior to the Closing Date or the Additional Closing Date, as the case may be, (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 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 subsection (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representatives may designate, such amendments or supplements to the 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 Representatives shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Shares; provided that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

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

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(h) Clear Market. For a period of 60 days after the date of the Prospectus, the Company will not (i) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase or otherwise transfer or dispose of, directly or indirectly, any shares of Stock or any securities convertible into or exercisable or exchangeable for Stock or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Stock, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise, without the prior written consent of the Representatives, other than (A) the Shares to be sold hereunder, (B) any options or other securities issued pursuant to transactions relating to existing director or employee stock option plans that are disclosed in the Prospectus or any shares of Stock of the Company issued upon the exercise of outstanding options or other securities granted under such existing director or employee stock option plans that are disclosed in the Prospectus, provided that such newly granted options and/or securities shall not vest during the 60-day restricted period, and (C) shares of Stock of the Company to be issued to one or more counterparties in connection with the consummation of a strategic partnership, joint venture, collaboration, merger or the acquisition or license of any assets, business products or technology, provided that in the case of issuances pursuant to this clause (C), the total aggregate number of shares of Stock issued shall not exceed five percent (5%) of the total shares of Stock outstanding immediately following the Closing Date and any recipients of such shares shall execute a lock-up agreement in substantially the form set forth in Annex C 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 restricted period, the restrictions imposed by this Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event, except that such extension will not apply if (x) the Company certifies to the Representatives and the Representatives confirm in writing their acknowledgement that the shares of Stock of the Company are “actively traded securities” (as defined in Regulation M under the Exchange Act) and the Company meets the applicable requirements of paragraph (a)(1) of Rule 139 under the Securities Act, in the manner contemplated by NASD Conduct Rule 2711(f)(4), and (y) the Representatives confirm in writing their acknowledgment that the provisions of NASD Conduct Rule 2711(f)(4) do not restrict the publishing or distribution of any research reports relating to the Company published or distributed by any of the Underwriters during the 15 days before or after the last day of the 60-day restricted period (before giving effect to such extension).

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

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

(k) Exchange Listing. The Company will use its best efforts to list, subject to notice of issuance, the Shares on the New York Stock Exchange.

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(l) Reports. During the period of five years hereafter, the Company will furnish to the Representatives, as soon as they are available, copies of all reports or other communications (financial or other) furnished to holders of the Shares, and copies of any reports and financial statements furnished to or filed with the Commission or any national securities exchange or automatic quotation system; provided the Company will be deemed to have furnished such reports and financial statements to the Representatives to the extent they are filed on EDGAR.

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

6. Further Agreements of the Selling Shareholders. Each Selling Shareholder, severally and not jointly, covenants and agrees with each Underwriter that:

(a) Clear Market. For a period of 60 days after the date of the Prospectus, the Selling Shareholders will not (i) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any shares of Stock or any securities convertible into or exercisable or exchangeable for Stock (including without limitation, Stock which may be deemed to be beneficially owned by the Selling Shareholders in accordance with the rules and regulations of the Commission and securities which may be issued upon exercise of a stock option or warrant) or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Stock, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Stock or such other securities, in cash or otherwise or (iii) make any demand for or exercise any right with respect to, the registration of any shares of Stock or any security convertible into or exercisable or exchangeable for Stock without the prior written consent of the Representatives, in each case other than (A) the Shares to be sold by the Selling Shareholders hereunder, (B) transfers of shares of Stock as a bona fide gift or gifts, provided, that in the case of any transfer or distribution pursuant to this clause (B), no filing by any party (donor, donee, transferor or transferee) under Section 16(a) of the Exchange Act shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on a Form 5 made after the expiration of the 60-day restricted period) and (C) the entry into any new, or the renewal or amendment of any existing, Rule 10b5-1 trading plan, provided that in connection with any such entry, renewal or amendment referred to in this clause (C), no shares of Stock shall be scheduled for sale thereunder during the 60-day restricted period and no public announcement or filing under the Exchange Act regarding such entry, renewal or amendment shall be required of or voluntarily made by or on behalf of the Selling Shareholders or the Company. 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 restricted period, the restrictions imposed by this Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event, except that such extension will not apply if (x) the Company certifies to the Representatives and the Representatives confirm in writing their acknowledgement that the shares of Stock of the Company are “actively traded securities” (as defined in Regulation M under the Exchange Act) and the Company meets the applicable requirements of paragraph (a)(1) of Rule 139 under the Securities Act, in the manner contemplated by NASD Conduct Rule 2711(f)(4), and (y) the Representatives confirm in writing their acknowledgment that the provisions of NASD Conduct Rule

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2711(f)(4) do not restrict the publishing or distribution of any research reports relating to the Company published or distributed by any of the Underwriters during the 15 days before or after the last day of the 60-day restricted period (before giving effect to such extension).

(b) Tax Form. The Selling Shareholders will deliver to the Representatives prior to or at the Closing Date a properly completed and executed United States Treasury Department Form W-9 (or other applicable form or statement specified by the Treasury Department regulations in lieu thereof) in order to facilitate the Underwriters’ documentation of their compliance with the reporting and withholding provisions of the Tax Equity and Fiscal Responsibility Act of 1982 with respect to the transactions herein contemplated.

7. 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 contains no “issuer information” (as defined in Rule 433(h)(2) under the Securities Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Annex A or prepared pursuant to Section 3(c) or Section 5(c) above (including any electronic road show), or (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing (each such free writing prospectus referred to in clauses (i) or (iii), an “Underwriter Free Writing Prospectus”). The Company represents that it has treated and agrees that it will treat each free writing prospectus referred to in clauses (ii) and (iii) above as an “issuer free writing prospectus,” as defined in Rule 433, and has complied and will comply with the requirements of Rule 433 applicable to any “issuer free writing prospectus,” including timely filing with the Commission where required, legending and record keeping.

(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 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.

8. 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 and the Selling Shareholders of their respective 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 each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 5(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Representatives.

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(b) Representations and Warranties. The respective representations and warranties of the Company and the Selling Shareholders 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 and the Selling Shareholders 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 its subsidiary 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 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 its subsidiary (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 Representatives makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Time of Sale Information and the Prospectus.

(e) Officer’s Certificate. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, in form and substance reasonably satisfactory to the Representatives, (A) a certificate of the chief financial officer or chief accounting officer of the Company and one additional senior executive officer of the Company who is satisfactory to the Representatives (i) confirming that such officers have carefully reviewed the Registration Statement, the Time of Sale Information and the Prospectus and, to the knowledge of such officers, the representations of the Company set forth in Sections 3(b) and 3(d) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date or the Additional Closing Date, as the case may be, and (iii) to the effect set forth in subsections (a), (b) and (c) above and (B) a certificate of the trustee of each Selling Shareholder (i) confirming that the representations of the Selling Shareholders set forth in Sections 4(f), 4(g), 4(h), 4(i) and 4(j) hereof are true and correct and (ii) confirming that the other representations and warranties of the Selling Shareholders in this agreement are true and correct and that the Selling Shareholders have complied with all agreements and satisfied all conditions on their part to be performed or satisfied hereunder at or prior to such Closing Date.

(f) Comfort Letters. On the date of this Agreement and on the Closing Date or the Additional Closing Date, as the case may be, Grant Thornton LLP shall have furnished to the Representatives, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or

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incorporated by reference in the Registration Statement, the Time of Sale Information and the Prospectus; provided, that the letter delivered on the Closing Date or the Additional Closing Date, as the case may be, shall use a “cut-off” date no more than three business days prior to such Closing Date or such Additional Closing Date, as the case may be.

(g) Reserve Letters. On the date of this Agreement and on the Closing Date or the Additional Closing Date, as the case may be, Ryder Scott Company, LP shall have furnished to the Representatives, at the request of the Company, reserve report confirmation letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, containing statements and information of the type customarily included in such letters to underwriters with respect to the reserve and other operational information contained in the Registration Statement, the Time of Sale Information and the Prospectus.

(h) Opinion of Counsel for the Company and the Selling Shareholders. (i) Conner & Winters, LLP, Oklahoma counsel for the Company and the Selling Shareholders, shall have furnished to the Representatives, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, to the effect set forth in Annex B-1 hereto and (ii) Latham & Watkins LLP, special counsel for the Company and the Selling Shareholders, shall have furnished to the Representatives, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, to the effect set forth in Annex B-2 hereto.

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

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

(k) Good Standing. The Representatives shall have received on and as of a date within one business day preceding the Closing Date or the Additional Closing Date, as the case may be, satisfactory evidence of the good standing of the Company and Banner, in their respective jurisdictions of organization and their good standing as foreign entities in such other jurisdictions as the Representatives may reasonably request, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

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

(m) Lock-up Agreements. The “lock-up” agreement substantially in the form of Annex C hereto, between you and Harold G. Hamm 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 in full force and effect on the Closing Date or the Additional Closing Date, as the case may be.

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

9. Indemnification and Contribution.

(a) Indemnification of the Underwriters by the Company. 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 (each, an “Underwriter Indemnified Person”), from and against any and all losses, claims, damages and liabilities (including, without limitation, legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, 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, or any untrue statement or alleged untrue statement of a material fact contained in the 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 Representatives expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (c) below.

(b) Indemnification of the Underwriters by the Selling Shareholders. Each Selling Shareholder, severally and not jointly, agrees to indemnify and hold harmless each Underwriter Indemnified Person to the same extent as the indemnity set forth in subsection (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 concerning or relating to the Selling Shareholders (or any trustee or beneficiary thereof) in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information.

(c) Indemnification of the Company and the Selling Shareholders. 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 and the Selling Shareholders to the same extent as the indemnity set forth in subsection (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

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such Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any 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 Prospectus furnished on behalf of each Underwriter: the information in the first paragraph under the heading “Underwriting—Commissions and Discounts,” the information in the second, third and fourth paragraphs under the heading “Underwriting—Price Stabilization, Short Positions” and the information under the heading “Underwriting—Electronic Offer, Sale and Distribution of Shares.”

(d) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to subsections (a), (b) or (c) 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 subsections (a), (b) or (c) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under subsections (a), (b) or (c) above. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person (who shall not, without the consent of the Indemnified Person, be counsel to the Indemnifying Person) to represent the Indemnified Person in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary 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. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing jointly by the Representatives, 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 and any such separate firm for the Selling Shareholders shall be designated in writing by the Selling Shareholders. 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 subsection, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance

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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.

(e) Contribution. If the indemnification provided for in subsections (a), (b) and (c) 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 subsection, 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 and the Selling Shareholders on the one hand and the Underwriters on the other from the offering of the Shares or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company and the Selling Shareholders on the one hand and the Underwriters on the other in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company and the Selling Shareholders on the one hand and the Underwriters on the other shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company and the Selling Shareholders 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 Prospectus, bear to the aggregate offering price of the Shares. The relative fault of the Company and the Selling Shareholders on the one hand and the Underwriters on the other shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company and the Selling Shareholders or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(f) Limitation on Liability. The Company, the Selling Shareholders and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 9 were determined by pro rata allocation (even if the Company and the Selling Shareholders or 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 subsection (e) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in subsection (e) 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 9, in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the Shares exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to this Section 9 are several in proportion to their respective purchase obligations hereunder and not joint.

(g) Non-Exclusive Remedies. The remedies provided for in this Section 9 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.

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

11. Termination. This Agreement may be terminated in the absolute discretion of the Representatives, by notice to the Company and the Selling Shareholders, 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, FINRA, The Nasdaq Stock Market, Inc. or The NASDAQ Stock Market LLC; (ii) trading of any securities issued or guaranteed by the Company shall have been suspended on any exchange or in any over-the-counter market; (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York State authorities; (iv) there shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, in the judgment of the Representatives, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Shares on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Time of Sale Information and the Prospectus; or (v) the representation in Section 3(b) is incorrect in any respect.

12. 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 and the Selling Shareholders 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 and the Selling Shareholders 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 and the Selling Shareholders 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, counsel for the Selling Shareholders or counsel for the Underwriters may be necessary in the Registration Statement and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “Underwriter” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule I hereto that, pursuant to this Section 12, 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, the Company and the Selling Shareholders as provided in subsection (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 and the Selling Shareholders 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.

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(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, the Company and the Selling Shareholders as provided in subsection (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 and the Selling Shareholders shall not exercise the right described in subsection (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 12 shall be without liability on the part of the Company and the Selling Shareholders, except that the Company will continue to be liable for the payment of expenses as set forth in Section 13 hereof and except that the provisions of Section 9 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, the Selling Shareholders or any non-defaulting Underwriter for damages caused by its default.

13. 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 Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the costs of reproducing and distributing the Underwriting Agreement; (iv) the fees and expenses of the Company’s counsel and independent accountants; (v) 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 Representatives may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related fees and expenses of counsel for the Underwriters); (vi) the cost of preparing stock certificates; (vii) the costs and charges of any transfer agent and any registrar; (viii) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, FINRA; and (ix) all expenses and application fees related to the listing of the Shares on the New York Stock Exchange.

(b) If (i) this Agreement is terminated pursuant to clauses (ii) or (v) of Section 11, (ii) the Company or the Selling Shareholders for any reason fail 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 clauses (i), (iii) or (iv) of Section 11), 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.

14. 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 9 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.

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15. Survival. The respective indemnities, rights of contribution, representations, warranties and agreements of the Company, the Selling Shareholders 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, the Selling Shareholders or the Underwriters.

16. 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.

17. Miscellaneous. (a) Authority of the Representatives. Any action by the Underwriters hereunder may be taken by the Representatives on behalf of the Underwriters, and any such action taken by the Representatives shall be binding upon the Underwriters.

(b) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to the Representatives c/o Merrill Lynch, Pierce, Fenner & Smith Incorporated, One Bryant Park, New York, New York 10036, attention of Syndicate Department (fax: (646) 855-3073) and ECM Legal (fax: (212) 230-8730) and J.P. Morgan Securities LLC, 383 Madison Avenue, New York, New York 10179, attention of Equity Syndicate Desk (fax: (212) 622-8358), with a copy to Davis Polk & Wardwell LLP, 450 Lexington Avenue, New York, New York 10017, (fax: (212) 701-5800); Attention: Joseph A. Hall. Notices to the Company shall be given to it at 302 N. Independence, Suite 1500, Enid, Oklahoma 73701, (fax: (580) 548-5253); Attention: John Hart, with a copy to Latham & Watkins LLP, 717 Texas Avenue, 16th Floor, Houston, Texas 77002, (fax: (713) 546-5401); Attention: Sean T. Wheeler, Esq. and to Conner & Winters, LLP, 4000 One Williams Center, Tulsa, Oklahoma 74172, (fax: (918) 586-8313); Attention: Robert Melgaard. Notices to the Selling Shareholders shall be given to the Selling Shareholders, in care of the Company at the address and fax number stated above, with a copy to Latham & Watkins LLP, 717 Texas Avenue, 16th Floor, Houston, Texas 77002, (fax: (713) 546-5401); Attention: Sean T. Wheeler, Esq.

(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.

Schedule I

Annex A

Time of Sale Information

1. Specify each free writing prospectus: None

2. The price to public of the Shares is $68.00 per Share

3. Number of Underwritten Shares: 10,000,000

A-1

Annex C

[Form of Lock-Up Agreement]

            , 2011

Merrill Lynch, Pierce, Fenner & Smith

    Incorporated

One Bryant Park

New York, New York 10036

J.P. Morgan Securities LLC

383 Madison Avenue

New York, New York 10179

Ladies and Gentlemen:

The undersigned understands that you, as Representatives of the several Underwriters, propose to enter into an Underwriting Agreement (the “Underwriting Agreement”) with Continental Resources, Inc., an Oklahoma corporation (the “Company”) and the selling shareholders named therein, providing for the public offering (the “Public Offering”) by the several Underwriters named in Schedule I thereto (the “Underwriters”), of common stock, par value $0.01 per share (the “Common Stock”) of the Company. Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Underwriting Agreement.

In consideration of the Underwriters’ agreement to purchase and make the Public Offering of the Common Stock, and for other good and valuable consideration receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of the Representatives on behalf of the Underwriters, the undersigned will not, during the period ending 60 days after the date of the final prospectus relating to the Public Offering (the “Prospectus”), (1) offer, pledge, announce the intention to sell, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (including without limitation, Common Stock which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of a stock option or warrant) or (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Common Stock, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise. In addition, the undersigned agrees that, without the prior written consent of the Representatives on behalf of the

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Underwriters, the undersigned will not, during the period ending 60 days after the date of the Prospectus, make any demand for or exercise any right with respect to, the registration of any shares of Common Stock or any security convertible into or exercisable or exchangeable for Common Stock. The foregoing shall not apply to (a) transfers of shares of Common Stock as a bona fide gift or gifts, provided, that in the case of any transfer or distribution pursuant to this clause (a), no filing by any party (donor, donee, transferor or transferee) under Section 16(a) of the Exchange Act shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on a Form 5 made after the expiration of the 60-day restricted period) and (b) the entry into any new, or the renewal or amendment of any existing, Rule 10b5-1 trading plan, provided that in connection with any such entry, renewal or amendment referred to in this clause (b), no shares of Common Stock shall be scheduled for sale thereunder during such 60-day restricted period and no public announcement or filing under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) regarding such entry, renewal or amendment shall be required of or voluntarily made by or on behalf of the undersigned or the Company. 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 restricted period, the restrictions imposed by this Letter Agreement shall continue to apply until the expiration of the 18-day period beginning on the issuance of the earnings release or the occurrence of the material news or material event, except that such extension will not apply if (x) the Company certifies to the Representatives and the Representatives confirm in writing their acknowledgement that the shares of Common Stock of the Company are “actively traded securities” (as defined in Regulation M under the Exchange Act) and the Company meets the applicable requirements of paragraph (a)(1) of Rule 139 under the Securities Act of 1933, as amended, in the manner contemplated by NASD Conduct Rule 2711(f)(4), and (y) the Representatives confirm in writing their acknowledgment that the provisions of NASD Conduct Rule 2711(f)(4) do not restrict the publishing or distribution of any research reports relating to the Company published or distributed by any of the Underwriters during the 15 days before or after the last day of the 60-day restricted period (before giving effect to such extension).

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

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

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

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

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