REGISTRATION RIGHTS AGREEMENT

Exhibit 4.1

EXECUTION COPY

REGISTRATION RIGHTS AGREEMENT

REGISTRATION RIGHTS AGREEMENT (this “Agreement”), dated as of May 18, 2007, by and among Continental Resources, Inc., an Oklahoma corporation (the “Company”), and the Revocable Inter Vivos Trust of Harold G. Hamm, the Harold Hamm DST Trust and the Harold Hamm HJ Trust (together, the “Principal Shareholders”).

WHEREAS, in connection with, and in consideration of, the transactions contemplated by the Company’s Registration Statement on Form S-1 (File No. 333-132257) initially filed with the SEC (as hereinafter defined) on March 7, 2006 and declared effective by the SEC under the Securities Act (as hereinafter defined) on May 14, 2007 (the “IPO Registration Statement”), the Principal Shareholders have requested, and the Company has agreed to provide, registration rights with respect to the Registrable Securities (as hereinafter defined), as set forth in this Agreement.

NOW, THEREFORE, for and in consideration of the mutual agreements contained herein and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged, the parties hereto, intending to be legally bound hereby, agree as follows:

Section 1. Definitions. As used in this Agreement, the following terms shall have the following meanings:

“Common Stock” shall mean the common stock, par value $.01 per share, of the Company.

“Demand Notice” shall have the meaning set forth in Section 3 hereof.

“Demand Registration” shall have the meaning set forth in Section 3 hereof.

“Demanding Qualified Holders” shall mean, with respect to any Demand Registration, the Qualified Holders delivering the relevant Demand Notice.

“Effectiveness Period” shall mean, with respect to any Shelf Registration Statement, the period from the date the Shelf Registration Statement is declared effective by the SEC until the earlier of:

(i) the sale of all of the Registrable Securities covered by such Shelf Registration Statement pursuant to such Shelf Registration Statement or pursuant to Rule 144 under the Securities Act or any similar provision then in effect; or

(ii) the time at which all of the Registrable Securities covered by the Shelf Registration Statement and not held by affiliates of the Company (as defined in Rule 144 under the Securities Act) are, in the opinion of counsel for the Company, eligible for sale pursuant to Rule 144(k) (or any successor or analogous rule) under the Securities Act.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended, and the rules and regulations of the SEC promulgated thereunder.

“Initial Public Offering” shall mean the underwritten registered initial public offering of equity securities of the Company pursuant to the IPO Registration Statement and completed as of the date hereof.

“Losses” shall have the meaning set forth in Section 8 hereof.

“Person” shall mean an individual, partnership, corporation, limited partnership, limited liability company, foreign limited liability company, trust, estate, corporation, custodian, trustee-executor, administrator, nominee or entity in a representative capacity.

“Piggyback Notice” shall have the meaning set forth in Section 4 hereof.

“Piggyback Registration” shall have the meaning as set forth in Section 4 hereof.

“Proceeding” shall mean an action, claim, suit, arbitration or proceeding (including, without limitation, an investigation or partial proceeding, such as a deposition), whether commenced or threatened.

“Prospectus” shall mean the prospectus included in any Registration Statement (including, without limitation, a prospectus that discloses information previously omitted from a prospectus filed as part of an effective Registration Statement in reliance upon Rules 430A, 430B or 430C promulgated under the Securities Act), as amended or supplemented by any prospectus supplement, with respect to the terms of the offering of any portion of the Registrable Securities covered by such Registration Statement, and all other amendments and supplements to the Prospectus, including post-effective amendments, and all material incorporated by reference or deemed to be incorporated by reference in such Prospectus.

“Qualified Holder” shall mean each of the Principal Shareholders and any other Person who becomes a Qualified Holder pursuant to Section 12(c), but only to the extent such Person continues to hold Registrable Securities.

“Registrable Securities” shall mean, subject to the next succeeding sentence, the shares of Common Stock held by the Principal Shareholders on the date of this Agreement, including any shares of Common Stock issued or distributed by way of dividend, stock split or other distribution in respect of such shares. As to any particular Registrable Securities, once issued, such securities shall cease to be Registrable Securities when (i) they are sold pursuant to an effective Registration Statement under the Securities Act, (ii) they are sold pursuant to Rule 144 (or any similar provision then in force under the Securities Act) and the transferee thereof does not receive “restricted securities” as defined in Rule 144, (iii) they shall have ceased to be outstanding, (iv) they have been sold in a private transaction in which the transferor’s rights under this Agreement are not assigned to the transferee of the securities, or (v) they become eligible for resale pursuant to Rule 144(k) (or any similar rule then in effect under the Securities Act). No Registrable Securities may be registered under more than one Registration Statement at any one time.

“Registration Statement” shall mean any registration statement of the Company under the Securities Act which permits the public offering of any of the Registrable Securities pursuant to the provisions of this Agreement, including the Prospectus, amendments and supplements to

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such registration statement, including post-effective amendments, all exhibits and all material incorporated by reference or deemed to be incorporated by reference in such registration statement.

“Rule 144” shall mean Rule 144 under the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the SEC.

“SEC” shall mean the Securities and Exchange Commission or any successor agency having jurisdiction under the Securities Act.

“Securities Act” shall mean the Securities Act of 1933, as amended, and the rules and regulations promulgated by the SEC thereunder.

“Shelf Registration Statement” shall mean a “shelf” Registration Statement pursuant to Rule 415 of the Securities Act.

“Suspension Notice” shall have the meaning set forth in Section 6(b).

“underwritten registration” or “underwritten offering” shall mean a registration in which securities of the Company are sold to an underwriter for reoffering to the public.

Section 2. Holders of Registrable Securities. A Person is deemed to be a holder of Registrable Securities whenever such Person owns Registrable Securities or holds an option, warrant or other right to purchase, or a security convertible into, Registrable Securities, whether or not such acquisition or conversion has actually been effected.

Section 3. Demand Registration.

(a) Requests for Registration. Commencing 180 days after the Initial Public Offering, a Qualified Holder shall have the right by delivering a written notice to the Company (the “Demand Notice”) to require the Company to register, pursuant to the terms of this Agreement under and in accordance with the provisions of the Securities Act, the number of Registrable Securities requested to be so registered pursuant to the terms of this Agreement (a “Demand Registration”). Following receipt of a Demand Notice for a Demand Registration, the Company shall use its reasonable best efforts to file a Registration Statement as promptly as practicable, but not later than 30 days, after such Demand Notice, and shall use its reasonable best efforts to cause such Registration Statement to be declared effective under the Securities Act as promptly as practicable after the filing thereof.

Each Principal Shareholder shall be entitled to a maximum of one Demand Registration, which, if such Demand Registration has not been exercised, may be transferred to any of such Principal Shareholder’s successors or assigns who becomes a Qualified Holder pursuant to Section 12(c); provided, however, that no such succession or assignment shall have the effect of increasing the number of Demand Registrations to be performed by the Company for the benefit of the shares held by such Principal Shareholder. Notwithstanding any other provisions of this Section 3, in no event shall more than one Demand Registration occur during any six-month period (measured from the effective date of the Registration Statement to the date of the next Demand Notice) or within 120 days after the effective date of a Registration Statement filed by the Company; provided that no Demand Registration may be prohibited for such 120-day period more often than once in a 12-month period.

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No Demand Registration shall be deemed to have occurred for purposes of this Section 3(a) if the Registration Statement relating thereto does not become effective or is not maintained effective for the period required pursuant to this Section 3(a), in which case the Demanding Qualified Holders shall be entitled to an additional Demand Registration in lieu thereof.

Within ten (10) days after receipt by the Company of a Demand Notice, the Company shall give written notice (the “Notice”) of such Demand Notice to all holders of Registrable Securities and shall, subject to the provisions of Section 3(b) hereof, include in such registration all Registrable Securities with respect to which the Company received written requests for inclusion therein within ten (10) days after such Notice is given by the Company to such holders.

All requests made pursuant to this Section 3 will specify the amount of Registrable Securities to be registered and the intended methods of disposition thereof.

The Company shall be required to maintain the effectiveness of the Registration Statement with respect to any Demand Registration for a period of at least 180 days after the effective date thereof or such shorter period in which all Registrable Securities included in such Registration Statement have actually been sold; provided, however, that such period shall be extended for a period of time equal to the period the holders of Registrable Securities refrain from selling any securities included in such registration at the request of an underwriter of the Company or the Company pursuant to this Agreement.

(b) Priority on Demand Registration. If any of the Registrable Securities registered pursuant to a Demand Registration are to be sold in a firm commitment underwritten offering, and the managing underwriter or underwriters advise the holders of such securities in writing that in its view the total amount of securities proposed to be sold in such offering is such as to adversely affect the success of such offering (including, without limitation, securities proposed to be included by other holders of securities entitled to include securities in the Registration Statement pursuant to incidental or piggyback registration rights), then the amount of securities to be offered (i) for the account of Demanding Qualified Holders and (ii) for the account of all such other Persons (other than the Demanding Qualified Holders) shall be reduced to the extent necessary to reduce the total amount of securities to be included in such offering to the amount recommended by such managing underwriter or underwriters by first reducing, or eliminating if necessary, all securities of the Company requested to be included by such other Persons and then, if necessary, reducing the Registrable Securities requested to be included by the Demanding Qualified Holders, pro rata among such members on the basis of the percentage of the Registrable Securities requested to be included in such Registration Statement by such members. In connection with any Demand Registration to which the provisions of this subsection (b) apply, no securities other than Registrable Securities shall be covered by such Demand Registration except as provided in subsection 3(d)(ii) hereof, and such registration shall not reduce the number of available registrations with respect to the Qualified Holders under this Section 3 in the event that the Registration Statement excludes more than 25% of the aggregate number of Registrable Securities that the Demanding Qualified Holders requested be included.

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(c) Postponement of Demand Registration. The Company shall be entitled to postpone (but not more than once in any twelve month period), for a reasonable period of time not in excess of 90 days, the filing of a Registration Statement if the Company delivers to the Demanding Qualified Holders a certificate signed by both the principal executive officer and the principal financial officer of the Company certifying that, in the good faith judgment of the Board of Directors of the Company, such registration and offering would reasonably be expected to materially adversely affect or materially interfere with any bona fide material financing of the Company or any material transaction under consideration by the Company or would require disclosure of information that has not been disclosed to the public, the premature disclosure of which would materially adversely affect the Company. Such certificate shall contain a statement of the reasons for such postponement and an approximation of the anticipated delay. The Persons receiving such certificate shall keep the information contained in such certificate confidential subject to the same terms set forth in Section 6(q). If the Company shall so postpone the filing of a Registration Statement, the Demanding Qualified Holders shall have the right to withdraw the request for registration by giving written notice to the Company within 20 days of the anticipated termination date of the postponement period, as provided in the certificate delivered thereto, and in the event of such withdrawal, such request shall not be counted for purposes of the number of Demand Registrations to which the Demanding Qualified Holder is entitled pursuant to the terms of this Agreement.

(d) Registration of Other Securities. Whenever the Company shall effect a Demand Registration pursuant to this Section 3 in connection with an underwritten offering, no securities other than Registrable Securities shall be included among the securities covered by such Demand Registration unless (i) the managing underwriter of such offering shall have advised each holder of Registrable Securities requesting such registration in writing that it believes that the inclusion of such other securities would not adversely affect such offering or (ii) the inclusion of such other securities is approved by the affirmative vote of the holders of at least a majority of the Registrable Securities included in such Demand Registration by the Demanding Qualified Holders.

Section 4. Piggyback Registration.

(a) Right to Piggyback. If, at any time after the Initial Public Offering, the Company proposes to file a Registration Statement under the Securities Act with respect to an offering of Common Stock (other than a registration statement (i) on Form S-4, Form F-4, Form S-8 or any successor forms thereto or (ii) filed solely in connection with an exchange offer or any employee benefit or dividend reinvestment plan), whether or not for its own account, then, each such time, the Company shall give prompt written notice of such proposed filing at least fifteen (15) days before the anticipated filing date (the “Piggyback Notice”) to all of the holders of Registrable Securities. The Piggyback Notice shall offer such holders the opportunity to include in such registration statement the number of Registrable Securities as each such holder may request (a “Piggyback Registration”). Subject to Section 4(b) hereof, the Company shall include in each such Piggyback Registration all Registrable Securities with respect to which the Company has received written requests for inclusion therein within ten (10) days after notice has

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been given to the applicable holder. The eligible holders of Registrable Securities shall be permitted to withdraw all or part of the Registrable Securities from a Piggyback Registration at any time prior to the effective date of such Piggyback Registration. The Company shall not be required to maintain the effectiveness of the Registration Statement for a Piggyback Registration beyond the earlier to occur of (i) 120 days after the effective date thereof and (ii) consummation of the distribution by the holders of the Registrable Securities included in such Registration Statement.

(b) Priority on Piggyback Registrations. The Company shall use reasonable efforts to cause the managing underwriter or underwriters of a proposed underwritten offering to permit holders of Registrable Securities requested to be included in the registration for such offering to include all such Registrable Securities on the same terms and conditions as any other shares of capital stock, if any, of the Company included therein. Notwithstanding the foregoing, if the managing underwriter or underwriters of such underwritten offering have informed the Company in writing that it is their good faith opinion that the total amount of securities that such holders, the Company and any other Persons having rights to participate in such registration, intend to include in such offering is such as to adversely affect the success of such offering, then the amount of securities to be offered (i) for the account of holders of Registrable Securities and (ii) for the account of all such other Persons (other than the Company and holders of Registrable Securities) shall be reduced to the extent necessary to reduce the total amount of securities to be included in such offering to the amount recommended by such managing underwriter or underwriters by first reducing, or eliminating if necessary, all securities of the Company requested to be included by such other Persons (other than the Company and holders of Registrable Securities) and then, if necessary, reducing the securities requested to be included by the holders of Registrable Securities requesting such registration pro rata among such holders on the basis of the percentage of the Registrable Securities requested to be included in such Registration Statement by such holders.

Section 5. Restrictions on Public Sale by Holders of Registrable Securities. Each holder of Registrable Securities agrees, in connection with the Initial Public Offering and any underwritten offering made pursuant to a Registration Statement filed pursuant to Section 3 or Section 4 hereof (whether or not such holder elected to include Registrable Securities in such Registration Statement), if requested (pursuant to a written notice) by the managing underwriter or underwriters in an underwritten offering, not to effect any public sale or distribution of any of the Company’s securities (except as part of such underwritten offering), including a sale pursuant to Rule 144, or to give any Demand Notice during the period commencing on the date of the request (which shall be no earlier than 14 days prior to the expected “pricing” of such offering) and continuing for not more than 90 days (with respect to any underwritten public offering made prior to the second anniversary of the Initial Public Offering and thereafter 60 days rather than 90) after the date of the Prospectus pursuant to which such public offering shall be made or such lesser period as is required by the managing underwriter, provided, however, that all officers and directors of the Company must be subject to similar restrictions.

Section 6. Registration Procedures. If and whenever the Company is required to use its reasonable best efforts to effect the registration of any Registrable Securities under the Securities Act as provided in Section 3 and Section 4 hereof, the Company shall effect such registration to permit the sale of such Registrable Securities in accordance with the intended method or methods of disposition thereof, and pursuant thereto the Company shall cooperate in the sale of the securities and shall, as expeditiously as possible:

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(a) Prepare and file with the SEC a Registration Statement or Registration Statements on such form which shall be available for the sale of the Registrable Securities by the holders thereof in accordance with the intended method or methods of distribution thereof, and use its reasonable best efforts to cause such Registration Statement to become effective and to remain effective as provided herein; provided, however, that before filing a Registration Statement or Prospectus or any amendments or supplements thereto (including documents that would be incorporated or deemed to be incorporated therein by reference), the Company shall furnish or otherwise make available to the holders of the Registrable Securities covered by such Registration Statement, their counsel and the managing underwriters, if any, copies of all such documents proposed to be filed. The Company shall not file any such Registration Statement or Prospectus or any amendments or supplements thereto (including such documents that, upon filing, would be incorporated or deemed to be incorporated by reference therein) with respect to a Demand Registration to which the holders of a majority of the Registrable Securities covered by such Registration Statement, their counsel, or the managing underwriters, if any, shall reasonably object, in writing, on a timely basis, unless, in the opinion of the Company, such filing is necessary to comply with applicable law.

(b) If such Registration Statement is a Shelf Registration Statement:

(i) Subject to any notice by the Company in accordance with this Section 6(b) of the existence of any fact or event of the kind described in Section 6(d)(vi), use its reasonable best efforts to keep the Shelf Registration Statement continuously effective during the Effectiveness Period; upon the occurrence of any event that would cause the Shelf Registration Statement or the Prospectus contained therein (A) to contain a material misstatement or omission or (B) not to be effective and usable for resale of the Registrable Securities covered thereby during the Effectiveness Period, the Company shall file promptly an appropriate amendment to the Shelf Registration Statement, a supplement to the Prospectus or a report filed with the SEC pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, in the case of clause (A) of this Section 6(b)(i), correcting any such misstatement or omission, and, in the case of either clause (A) or (B) of this Section 6(b)(i), use its reasonable best efforts to cause such amendment to be declared effective and the Shelf Registration Statement and the related Prospectus to become usable for their intended purposes as soon as practicable thereafter.

(ii) Notwithstanding Section 6(b)(i) hereof, the Company may suspend the effectiveness of the Shelf Registration Statement (each such period, a “Suspension Period”):

(A) if a majority of the Company’s board of directors, in good faith, determines that (1) the offer or sale of any shares of Common Stock would materially impede, delay or interfere with any proposed financing, offer or sale of securities, acquisition, merger, tender offer, business combination, corporate reorganization, consolidation or other significant

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transaction involving the Company, (2) after the advice of counsel, the sale of the shares of Common Stock covered by the Shelf Registration Statement would require disclosure of non-public material information not otherwise required to be disclosed under applicable law, and (3) either (x) the Company has a bona fide business purpose for preserving the confidentiality of the proposed transaction, (y) disclosure would have a material adverse effect on the Company or the Company’s ability to consummate the proposed transaction, or (z) the proposed transaction renders the Company unable to comply with requirements of the SEC; or

(B) if a majority of the Company’s board of directors, in good faith, determines that the Company is required by law, rule or regulation to supplement the Shelf Registration Statement or file a post-effective amendment to the Shelf Registration Statement in order to incorporate information into the Shelf Registration Statement for the purpose of (1) including in the Shelf Registration Statement any Prospectus required under Section 10(a)(3) of the Securities Act, (2) reflecting in the Prospectus included in the Shelf Registration Statement any facts or events arising after the effective date of the Shelf Registration Statement (or the most recent post-effective amendment) that, individually or in the aggregate, represents a fundamental change in the information set forth in the Prospectus, or (3) including in the Prospectus included in the Shelf Registration Statement any material information with respect to the plan of distribution not disclosed in the Shelf Registration Statement or any material change to such information.

Upon the occurrence of any event described in clauses (A) and (B) of this Section 6(b)(ii), the Company shall give notice to each Demanding Qualified Holder with respect to such Shelf Registration Statement that the availability of the Shelf Registration is suspended and, upon actual receipt of any such notice, each such Demanding Qualified Holder agrees not to sell any Registrable Securities pursuant to the Shelf Registration Statement until such Demanding Qualified Holder’s receipt of copies of the supplemented or amended Prospectus provided for this Section 6(b). The Suspension Period shall not exceed 60 days in any 90-day period (except as a result of a review of any post-effective amendment by the SEC prior to declaring any post-effective amendment to the Shelf Registration Statement effective provided the Company has used its reasonable best efforts to cause such post-effective amendment to be declared effective); provided, that Suspension Periods shall not exceed an aggregate of 120 days in any 12-month period. The Company shall not be required to specify in the written notice to the Qualified Holders the nature of the event giving rise to the Suspension Period.

(c) Prepare and file with the SEC such amendments and post-effective amendments to each Registration Statement as may be necessary to keep such Registration Statement continuously effective during the period provided herein with respect to the disposition of all securities covered by such Registration Statement; and cause the related Prospectus to be supplemented by any Prospectus supplement as may be necessary to comply

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with the provisions of the Securities Act with respect to the disposition of the securities covered by such Registration Statement, and as so supplemented to be filed pursuant to Rule 424 (or any similar provisions then in force) under the Securities Act.

(d) Notify each selling holder of Registrable Securities, its counsel and the managing underwriters, if any, promptly, and (if requested by any such Person) confirm such notice in writing (which notice pursuant to clauses (ii) through (v) below shall be accompanied by an instruction to suspend the use of the Prospectus until the Company shall have remedied the basis for such suspension if the effectiveness of a Shelf Registration Statement has been suspended pursuant to Section 6(b)), (i) when a Prospectus or any Prospectus supplement or post-effective amendment has been filed, and, with respect to a Registration Statement or any post-effective amendment, when the same has become effective, (ii) of any request by the SEC or any other Federal or state governmental authority for amendments or supplements to a Registration Statement or related Prospectus or for additional information, (iii) of the issuance by the SEC of any stop order suspending the effectiveness of a Registration Statement or the initiation of any proceedings for that purpose, (iv) if at any time the representations and warranties of the Company contained in any agreement (including any underwriting agreement) contemplated by Section 6(p) below cease to be true and correct, (v) of the receipt by the Company of any notification with respect to the suspension of the qualification or exemption from qualification of any of the Registrable Securities for sale in any jurisdiction, or the initiation or threatening of any proceeding for such purpose, and (vi) of the happening of any event that makes any statement made in such Registration Statement or related Prospectus or any document incorporated or deemed to be incorporated therein by reference untrue in any material respect or that requires the making of any changes in such Registration Statement, Prospectus or documents so that, in the case of the Registration Statement, it will not contain any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein, not misleading, and that in the case of the Prospectus, it will not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading.

(e) Use its reasonable best efforts to obtain the withdrawal of any order suspending the effectiveness of a Registration Statement, or the lifting of any suspension of the qualification (or exemption from qualification) of any of the Registrable Securities for sale in any jurisdiction.

(f) If requested by the managing underwriters, if any, or the holders of a majority of the then outstanding Registrable Securities being sold in connection with an underwritten offering, promptly include in a Prospectus supplement or post-effective amendment such information as the managing underwriters, if any, and such holders may reasonably request in order to permit the intended method of distribution of such securities and make all required filings of such Prospectus supplement or such post-effective amendment as soon as practicable after the Company has received such request; provided, however, that the Company shall not be required to take any actions under this Section 6(f) that are not, in the opinion of counsel for the Company, in compliance with applicable law.

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(g) Furnish to each selling holder of Registrable Securities, its counsel and each managing underwriter, if any, without charge, at least one conformed copy of the Registration Statement, the Prospectus and Prospectus supplements, if applicable, and each post-effective amendment thereto, including financial statements (but excluding schedules, all documents incorporated or deemed to be incorporated therein by reference, and all exhibits, unless requested in writing by such holder, counsel or underwriter).

(h) Deliver to each selling holder of Registrable Securities, its counsel, and the underwriters, if any, without charge, as many copies of the Prospectus or Prospectuses (including each form of Prospectus) and each amendment or supplement thereto as such Persons may reasonably request in connection with the distribution of the Registrable Securities; and the Company, subject to the last paragraph of this Section 6, hereby consents to the use of such Prospectus and each amendment or supplement thereto by each of the selling holders of Registrable Securities and the underwriters, if any, in connection with the offering and sale of the Registrable Securities covered by such Prospectus and any such amendment or supplement thereto.

(i) Prior to any public offering of Registrable Securities, use its reasonable best efforts to register or qualify or cooperate with the selling holders of Registrable Securities, the underwriters, if any, and their respective counsel in connection with the registration or qualification (or exemption from such registration or qualification) of such Registrable Securities for offer and sale under the securities or “Blue Sky” laws of such jurisdictions within the United States or Canada as any seller or underwriter reasonably requests in writing and to keep each such registration or qualification (or exemption therefrom) effective during the period such Registration Statement is required to be kept effective and to take any other action that may be necessary or advisable to enable such holders of Registrable Securities to consummate the disposition of such Registrable Securities in such jurisdiction; provided, however, that the Company will not be required to (i) qualify generally to do business in any jurisdiction where it is not then so qualified or (ii) take any action that would subject it to general service of process in any such jurisdiction where it is not then so subject.

(j) Cooperate with the selling holders of Registrable Securities and the managing underwriters, if any, to facilitate the timely preparation and delivery of certificates (not bearing any legends) representing Registrable Securities to be sold after receiving written representations from each holder of such Registrable Securities that the Registrable Securities represented by the certificates so delivered by such holder will be transferred in accordance with the Registration Statement, and enable such Registrable Securities to be in such denominations and registered in such names as the managing underwriters, if any, or holders may request at least two (2) business days prior to any sale of Registrable Securities in a firm commitment public offering, but in any other such sale, within ten (10) business days prior to having to issue the securities.

(k) Use its reasonable best efforts to cause the Registrable Securities covered by the Registration Statement to be registered with or exempted from registration or qualification or approved by such other governmental agencies or authorities within the United States or Canada, except as may be required solely as a consequence of the nature of such selling holder’s business, in which case the Company will cooperate in all reasonable respects with the filing of

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such Registration Statement and the granting of such approvals, as may be necessary to enable the seller or sellers thereof or the underwriters, if any, to consummate the disposition of such Registrable Securities.

(l) Upon the occurrence of any event contemplated by Section 6(d)(vi) above, prepare a supplement or post-effective amendment to the Registration Statement or a supplement to the related Prospectus or any document incorporated or deemed to be incorporated therein by reference, or file any other required document so that, as thereafter delivered to the purchasers of the Registrable Securities being sold thereunder, such Prospectus will not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading.

(m) Prior to the effective date of the Registration Statement relating to the Registrable Securities, provide a CUSIP number for the Registrable Securities.

(n) Provide and cause to be maintained a transfer agent and registrar for all Registrable Securities covered by such Registration Statement from and after a date not later than the effective date of such Registration Statement.

(o) Use its reasonable best efforts to cause all shares of Registrable Securities covered by such Registration Statement to be authorized to be listed on the New York Stock Exchange or listed on another national securities exchange or quoted on the Nasdaq National Market if shares of the particular class of Registrable Securities are at that time listed on such exchange or quoted on the Nasdaq National Market, as the case may be.

(p) Enter into such agreements (including an underwriting agreement in form, scope and substance as is customary in underwritten offerings) and take all such other actions reasonably requested by the holders of a majority of the Registrable Securities being sold in connection therewith (including those reasonably requested by the managing underwriters, if any) to expedite or facilitate the disposition of such Registrable Securities, and in such connection, whether or not an underwriting agreement is entered into and whether or not the registration is an underwritten registration, (i) make such representations and warranties to the holders of such Registrable Securities and the underwriters, if any, with respect to the business of the Company and its subsidiaries, and the Registration Statement, Prospectus and documents, if any, incorporated or deemed to be incorporated by reference therein, in each case, in form, substance and scope as are customarily made by issuers to underwriters in underwritten offerings, and, if true, confirm the same if and when requested, (ii) use its reasonable best efforts to furnish to the selling holders of such Registrable Securities opinions of counsel to the Company and updates thereof (which counsel and opinions (in form, scope and substance) shall be reasonably satisfactory to the managing underwriters, if any, and counsels to the selling holders of the Registrable Securities), addressed to each selling holder of Registrable Securities and each of the underwriters, if any, covering the matters customarily covered in opinions requested in underwritten offerings and such other matters as may be reasonably requested by such counsel and underwriters, (iii) use its reasonable best efforts to obtain “cold comfort” letters and updates thereof from the independent certified public accountants of the Company (and, if necessary, any other independent certified public accountants of any subsidiary of the Company

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or of any business acquired by the Company for which financial statements and financial data are, or are required to be, included in the Registration Statement) who have certified the financial statements included in such Registration Statement, addressed to each selling holder of Registrable Securities (unless such accountants shall be prohibited from so addressing such letters by applicable standards of the accounting profession) and each of the underwriters, if any, such letters to be in customary form and covering matters of the type customarily covered in “cold comfort” letters in connection with underwritten offerings, (iv) if an underwriting agreement is entered into, the same shall contain indemnification provisions and procedures substantially to the effect set forth in Section 8 hereof with respect to all parties to be indemnified pursuant to said Section and (v) deliver such documents and certificates as may be reasonably requested by the holders of a majority of the Registrable Securities being sold, their counsel and the managing underwriters, if any, to evidence the continued validity of the representations and warranties made pursuant to clause (i) of this Section 6(p) and to evidence compliance with any customary conditions contained in the underwriting agreement or other agreement entered into by the Company. The above shall be done at each closing under such underwriting or similar agreement, or as and to the extent required thereunder.

(q) Make available for inspection by a representative of the selling holders of Registrable Securities, any underwriter participating in any such disposition of Registrable Securities, if any, and any attorneys or accountants retained by such selling holders or underwriter, at the offices where normally kept, during reasonable business hours, all financial and other records, pertinent corporate documents and properties of the Company and its subsidiaries, and cause the officers, directors and employees of the Company and its subsidiaries to supply all information in each case reasonably requested by any such representative, underwriter, attorney or accountant in connection with such Registration Statement; provided, however, that any information that is not generally publicly available at the time of delivery of such information shall be kept confidential by such Persons unless (i) disclosure of such information is required by court or administrative order, (ii) disclosure of such information, in the opinion of counsel to such Person, is required by law, or (iii) such information becomes generally available to the public other than as a result of a disclosure or failure to safeguard by such Person. In the case of a proposed disclosure pursuant to (i) or (ii) above, such Person shall be required to give the Company written notice of the proposed disclosure prior to such disclosure and, if requested by the Company, assist the Company in seeking to prevent or limit the proposed disclosure. Without limiting the foregoing, no such information shall be used by such Person as the basis for any market transactions in securities of the Company or its subsidiaries in violation of law.

(r) Comply with all applicable rules and regulations of the SEC and make available to its security holders earning statements satisfying the provisions of Section 11(a) of the Securities Act and Rule 158 thereunder, or any similar rule promulgated under the Securities Act, no later than forty-five (45) days after the end of any twelve (12) month period (or ninety (90) days after the end of any twelve (12) month period if such period is a fiscal year) (i) commencing at the end of any fiscal quarter in which Registrable Securities are sold to underwriters in a firm commitment or best efforts underwritten offering and (ii) if not sold to underwriters in such an offering, commencing on the first day of the first fiscal quarter of the Company after the effective date of a Registration Statement, which statements shall cover one of said twelve (12) month periods.

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(s) Cause its officers to use their reasonable best efforts to support the marketing of the Registrable Securities covered by the Registration Statement (including, without limitation, participation in “road shows”) taking into account the Company’s business needs.

The Company may require each seller of Registrable Securities as to which any registration is being effected to furnish to the Company in writing such information required in connection with such registration regarding such seller and the distribution of such Registrable Securities as the Company may, from time to time, reasonably request in writing and the Company may exclude from such registration the Registrable Securities of any seller who unreasonably fails to furnish such information within a reasonable time after receiving such request.

Each holder of Registrable Securities agrees if such holder has Registrable Securities covered by such Registration Statement that, upon receipt of any notice from the Company of the happening of any event of the kind described in Section 6(d)(ii), 6(d)(iii), 6(d)(v) or 6(d)(vi) hereof, such holder will forthwith discontinue disposition of such Registrable Securities covered by such Registration Statement or Prospectus until such holder’s receipt of the copies of the supplemented or amended Prospectus contemplated by Section 6(l) hereof, or until it is advised in writing by the Company that the use of the applicable Prospectus may be resumed, and has received copies of any additional or supplemental filings that are incorporated or deemed to be incorporated by reference in such Prospectus; provided, however that the Company shall extend the time periods under Section 3 with respect to the length of time that the effectiveness of a Registration Statement must be maintained by the amount of time the holder is required to discontinue disposition of such securities.

Section 7. Registration Expenses. All reasonable fees and expenses incident to the performance of or compliance with this Agreement by the Company (including, without limitation, (i) all registration and filing fees (including, without limitation, fees and expenses (A) with respect to filings required to be made with the National Association of Securities Dealers, Inc. and (B) of compliance with securities or Blue Sky laws, including, without limitation, any fees and disbursements of counsel for the underwriters in connection with Blue Sky qualifications of the Registrable Securities pursuant to Section 6(i)), (ii) printing expenses (including, without limitation, expenses of printing certificates for Registrable Securities in a form eligible for deposit with The Depository Trust Company and of printing Prospectuses if the printing of Prospectuses is requested by the managing underwriters, if any, or by the holders of a majority of the Registrable Securities included in any Registration Statement), (iii) messenger, telephone and delivery expenses of the Company, (iv) fees and disbursements of counsel for the Company, (v) expenses of the Company incurred in connection with any road show, (vi) fees and disbursements of all independent certified public accountants referred to in Section 6(p)(iii) hereof (including, without limitation, the expenses of any “cold comfort” letters required by this Agreement) and any other persons, including special experts retained by the Company, and (vii) fees and disbursements of one counsel for the Qualified Holders whose Registrable Securities are included in a Registration Statement, which counsel shall be selected by the holders of a majority of the Registrable Securities held by the Qualified Holders included in such Registration Statement) shall be borne by the Company whether or not any Registration Statement is filed or becomes effective. In addition, the Company shall pay its internal expenses

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(including, without limitation, all salaries and expenses of its officers and employees performing legal or accounting duties), the expense of any annual audit, the fees and expenses incurred in connection with the listing of the securities to be registered on any securities exchange on which similar securities issued by the Company are then listed and rating agency fees and the fees and expenses of any Person, including special experts, retained by the Company.

The Company shall not be required to pay (i) fees and disbursements of any counsel retained by any holder of Registrable Securities or by any underwriter (except as set forth in clauses 7(i)(B) and 7(vii)), (ii) any underwriter’s fees (including discounts, commissions or fees of underwriters, selling brokers, dealer managers or similar securities industry professionals) relating to the distribution of the Registrable Securities, or (iii) any other expenses of the holders of Registrable Securities not specifically required to be paid by the Company pursuant to the first paragraph of this Section 7.

Section 8. Indemnification.

(a) Indemnification by the Company. The Company shall, without limitation as to time, indemnify and hold harmless, to the fullest extent permitted by law, each holder of Registrable Securities whose Registrable Securities are covered by a Registration Statement or Prospectus, the officers, directors, partners, members, managers, stockholders, accountants, attorneys, agents and employees of each of them, each Person who controls each such holder (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) and the officers, directors, partners, members, managers, stockholders, accountants, attorneys, agents and employees of each such controlling person, each underwriter, if any, and each Person who controls (within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act) such underwriter, from and against any and all losses, claims, damages, liabilities, costs (including, without limitation, costs of preparation and reasonable attorneys’ fees and any legal or other fees or expenses incurred by such party in connection with any investigation or Proceeding), expenses, judgments, fines, penalties, charges and amounts paid in settlement (collectively, “Losses”), as incurred, arising out of or based upon any untrue statement of a material fact contained in any Prospectus, Prospectus supplement, offering circular, or other document (including any related Registration Statement, notification, or the like) incident to any such registration, qualification, or compliance, or based on any omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, or any violation by the Company of the Securities Act or any rule or regulation thereunder applicable to the Company and relating to action or inaction required of the Company in connection with any such registration, qualification, or compliance, and will reimburse each such holder, each of its officers, directors, partners, members, managers, stockholders, accountants, attorneys, agents and employees and each person controlling such holder, each such underwriter, and each person who controls any such underwriter, for any legal and any other expenses reasonably incurred in connection with investigating and defending or settling any such claim, loss, damage, liability, or action, provided that the Company will not be liable in any such case to the extent that any such claim, loss, damage, liability, or expense arises out of or is based on any untrue statement or omission by such holder or underwriter, but only to the extent, that such untrue statement or omission is made in such Registration Statement, Prospectus, Prospectus supplement, offering circular, or other document in reliance upon and in conformity with written information furnished to the Company by such holder. It is agreed that the

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indemnity agreement contained in this Section 8(a) shall not apply to amounts paid in settlement of any such loss, claim, damage, liability, or action if such settlement is effected without the consent of the Company (which consent shall not be unreasonably withheld).

(b) Indemnification by Holder of Registrable Securities. In connection with any Registration Statement in which a holder of Registrable Securities is participating, such holder of Registrable Securities shall furnish to the Company in writing such information as the Company reasonably requests for use in connection with any Registration Statement or Prospectus and agrees to indemnify, to the fullest extent permitted by law, severally and not jointly, the Company, its directors, officers, accountants, attorneys, agents and employees, each Person who controls the Company (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the directors, officers, partners, members, managers, stockholders, accountants, attorneys, agents or employees of such controlling persons, and each underwriter, if any, and each person who controls such underwriter (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act), from and against all Losses arising out of or based on any untrue statement of a material fact contained in any such Registration Statement, Prospectus, Prospectus supplement, offering circular, or other document, or any omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and will reimburse the Company and such directors, officers, partners, members, managers, stockholders, accountants, attorneys, employees, agents, persons, underwriters, or control persons for any legal or any other expenses reasonably incurred in connection with investigating or defending any such claim, loss, damage, liability, or action, in each case to the extent, but only to the extent, that such untrue statement or omission is made in such Registration Statement, Prospectus, Prospectus supplement, offering circular, or other document in reliance upon and in conformity with written information furnished to the Company by such holder specifically for use in connection with the preparation of such Registration Statement, Prospectus, Prospectus supplement, offering circular or other document; provided, however, that the obligations of such holder hereunder shall not apply to amounts paid in settlement of any such claims, losses, damages, or liabilities (or actions in respect thereof) if such settlement is effected without the consent of such holder (which consent shall not be unreasonably withheld); and provided, further, that the liability of each selling holder of Registrable Securities hereunder shall be limited to the net proceeds received by such selling holder from the sale of Registrable Securities covered by such Registration Statement. In addition, insofar as the foregoing indemnity relates to any such untrue statement or omission made in the preliminary Prospectus but eliminated or remedied in the amended Prospectus on file with the SEC at the time the Registration Statement becomes effective or in the final Prospectus filed pursuant to applicable rules of the SEC or in any supplement or addendum thereto and such new Prospectus is delivered to the underwriter, the indemnity agreement herein shall not inure to the benefit of such underwriter, any controlling person of such underwriter and their respective Representatives, if a copy of the final Prospectus filed pursuant to such rules, together with all supplements and addenda thereto was not furnished to the Person asserting the loss, liability, claim or damage at or prior to the time such furnishing is required by the Securities Act.

(c) Conduct of Indemnification Proceedings. If any Person shall be entitled to indemnity hereunder (an “indemnified party”), such indemnified party shall give prompt notice to the party from which such indemnity is sought (the “indemnifying party”) of any claim or of the commencement of any Proceeding with respect to which such indemnified party seeks

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indemnification or contribution pursuant hereto; provided, however, that the delay or failure to so notify the indemnifying party shall not relieve the indemnifying party from any obligation or liability except to the extent that the indemnifying party has been prejudiced by such delay or failure. The indemnifying party shall have the right, exercisable by giving written notice to an indemnified party promptly after the receipt of written notice from such indemnified party of such claim or Proceeding, to, unless in the indemnified party’s reasonable judgment a conflict of interest between such indemnified and indemnifying parties may exist in respect of such claim, assume, at the indemnifying party’s expense, the defense of any such claim or Proceeding, with counsel reasonably satisfactory to such indemnified party; provided, however, that an indemnified party shall have the right to employ separate counsel in any such claim or Proceeding and to participate in the defense thereof, but the fees and expenses of such counsel shall be at the expense of such indemnified party unless: (i) the indemnifying party agrees to pay such fees and expenses; or (ii) the indemnifying party fails promptly to assume the defense of such claim or Proceeding or fails to employ counsel reasonably satisfactory to such indemnified party; in which case the indemnified party shall have the right to employ counsel and to assume the defense of such claim or proceeding; provided, however, that the indemnifying party shall not, in connection with any one such claim or Proceeding or separate but substantially similar or related claims or Proceedings in the same jurisdiction, arising out of the same general allegations or circumstances, be liable for the fees and expenses of more than one firm of attorneys (together with appropriate local counsel) at any time for all of the indemnified parties, or for fees and expenses that are not reasonable. Whether or not such defense is assumed by the indemnifying party, such indemnified party will not be subject to any liability for any settlement made without its consent (but such consent will not be unreasonably withheld). The indemnifying party shall not consent to entry of any judgment or enter into any settlement that does not include as an unconditional term thereof the giving by the claimant or plaintiff to such indemnified party of a release, in form and substance reasonably satisfactory to the indemnified party, from all liability in respect of such claim or litigation for which such indemnified party would be entitled to indemnification hereunder.

(d) Contribution. If the indemnification provided for in this Section 8 is unavailable to an indemnified party in respect of any Losses (other than in accordance with its terms), then each applicable indemnifying party, in lieu of indemnifying such indemnified party, shall contribute to the amount paid or payable by such indemnified party as a result of such Losses, in such proportion as is appropriate to reflect the relative fault of the indemnifying party, on the one hand, and such indemnified party, on the other hand, in connection with the actions, statements or omissions that resulted in such Losses as well as any other relevant equitable considerations. The relative fault of such indemnifying party, on the one hand, and indemnified party, on the other hand, shall be determined by reference to, among other things, whether any action in question, including any untrue or alleged untrue statement of a material fact or omission or alleged omission to state a material fact, has been taken by, or relates to information supplied by, such indemnifying party or indemnified party, and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent any such action, statement or omission.

The parties hereto agree that it would not be just and equitable if contribution pursuant to this Section 8(d) were determined by pro rata allocation or by any other method of allocation that does not take account of the equitable considerations referred to in the

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immediately preceding paragraph. Notwithstanding the provisions of this Section 8(d), an indemnifying party that is a selling holder of Registrable Securities shall not be required to contribute any amount in excess of the amount by which the net proceeds from the sale of the Registrable Securities sold by such indemnifying party exceeds the amount of any damages that such indemnifying party 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.

(e) Notwithstanding the foregoing, to the extent that the provisions on indemnification and contribution contained in the underwriting agreement entered into in connection with the underwritten public offering are in conflict with the foregoing provisions, the provisions in the underwriting agreement shall control.

Section 9. Rule 144. After the Initial Public Offering, the Company shall file the reports required to be filed by it under the Securities Act and the Exchange Act, and will take such further action as any holder of Registrable Securities may reasonably request, all to the extent required from time to time to enable such holder to sell Registrable Securities without registration under the Securities Act within the limitations of the exemption provided by Rule 144. Upon the request of any holder of Registrable Securities, the Company shall deliver to such holder a written statement as to whether it has complied with such requirements.

Section 10. Underwritten Registrations. If any Demand Registration is an underwritten offering, the Company shall have the right to select the investment banker or investment bankers and managers to administer the offering, subject to approval by the holders of a majority of the Registrable Securities covered by such Demand Registration, not to be unreasonably withheld. The Company shall have the right to select the investment banker or investment bankers and managers to administer any Piggyback Registration.

No Person may participate in any underwritten registration hereunder unless such Person (i) agrees to sell the Registrable Securities it desires to have covered by the Demand Registration on the basis provided in any underwriting arrangements in customary form and (ii) completes and executes all questionnaires, powers of attorney, custody agreements, indemnities, underwriting agreements and other documents required under the terms of such underwriting arrangements, provided that such Person shall not be required to make any representations or warranties other than those related to title and ownership of shares and as to the accuracy and completeness of statements made in a Registration Statement, Prospectus, offering circular, or other document in reliance upon and in conformity with written information furnished to the Company or the managing underwriter by such Person.

Section 11. Limitation on Subsequent Registration Rights. The Company represents and warrants that it has not granted to any Person the right to request or require the Company to register any securities issued by the Company. From and after the date of this Agreement, the Company shall not, without the prior written consent of the holders of at least a majority of the then outstanding Registrable Securities, enter into any agreement with any holder or prospective holder of any securities of the Company giving such holder or prospective holder any registration rights the terms of which would reduce the amount of Registrable Securities the holders can include in any registration filed pursuant to Section 3 or Section 4 hereof, unless such rights are subordinate to those of the holders of Registrable Securities.

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Section 12. Miscellaneous.

(a) Amendments and Waivers. The provisions of this Agreement, including the provisions of this sentence, may not be amended, modified or supplemented, and waivers or consents to departures from the provisions hereof may not be given, unless the Company has obtained the written consent of holders of at least a majority of the then outstanding Registrable Securities; provided, however, that in no event shall the obligations of any holder of Registrable Securities be materially increased or the rights of any holder of Registrable Securities be adversely affected (without similarly adversely affecting the rights of all holders of Registrable Securities), except upon the written consent of such holder. Notwithstanding the foregoing, a waiver or consent to depart from the provisions hereof with respect to a matter that relates exclusively to the rights of holders of Registrable Securities whose securities are being sold pursuant to a Registration Statement and that does not directly or indirectly affect the rights of other holders of Registrable Securities may be given by holders of at least a majority of the Registrable Securities being sold by such holders pursuant to such Registration Statement.

(b) Notices. All notices required to be given hereunder shall be in writing and shall be deemed to be duly given if personally delivered, telecopied and confirmed, or mailed by certified mail, return receipt requested, or overnight delivery service with proof of receipt maintained, at the following address (or any other address that any such party may designate by written notice to the other parties):

if to the Company:

Mark E. Monroe

President and Chief Operating Officer

302 N. Independence

Enid, Oklahoma 73701

Fax: (580)  ###-###-####

and a copy to:

David P. Oelman

Vinson & Elkins L.L.P.

2300 First City Tower

1001 Fannin Street

Houston, Texas 77002

Fax: (713)  ###-###-####

If to any holder of Registrable Securities, at such Person’s address as set forth on the records of the Company. Any such notice shall, if delivered personally, be deemed received upon delivery; shall, if delivered by telecopy, be deemed received on the first business day following confirmation; shall, if delivered by overnight delivery service, be deemed received the first business day after being sent; and shall, if delivered by mail, be deemed received upon the earlier of actual receipt thereof or five business days after the date of deposit in the United States mail.

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(c) Successors and Assigns; Status. This Agreement shall inure to the benefit of and be binding upon the successors and assigns of each of the parties, including subsequent holders of Registrable Securities; provided, however, that such successor or assign shall not be entitled to such rights unless the successor or assign shall have executed and delivered to the Company an Addendum Agreement substantially in the form of Exhibit A hereto promptly following the acquisition of such Registrable Securities, in which event such successor or assign shall be deemed a Qualified Holder for purposes of this Agreement. Nothing expressed or mentioned in this Agreement is intended or shall be construed to give any Person other than the parties hereto and their respective permitted successors and assigns any legal or equitable right, remedy or claim under, in or in respect of this Agreement or any provision herein contained.

(d) Counterparts. This Agreement may be executed in two or more counterparts, each of which shall be deemed an original, but all of which together shall constitute one and the same instrument.

(e) Headings. The section and paragraph headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation of this Agreement.

(f) Governing Law. This agreement shall be governed by and construed in accordance with the laws of the State of Oklahoma.

(g) Severability. If any term, provision, covenant or restriction of this Agreement is held by a court of competent jurisdiction to be invalid, illegal, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions set forth herein shall remain in full force and effect and shall in no way be affected, impaired or invalidated, and the parties hereto shall use their best efforts to find and employ an alternative means to achieve the same or substantially the same result as that contemplated by such term, provision, covenant or restriction. It is hereby stipulated and declared to be the intention of the parties that they would have executed the remaining terms, provisions, covenants and restrictions without including any of such that may be hereafter declared invalid, illegal, void or unenforceable.

(h) Entire Agreement. This Agreement is intended by the parties as a final expression of their agreement, and is intended to be a complete and exclusive statement of the agreement and understanding of the parties hereto in respect of the subject matter contained herein. There are no restrictions, promises, warranties or undertakings, other than those set forth or referred to herein, with respect to the registration rights granted by the Company with respect to Registrable Securities. This Agreement supersedes all prior agreements and understandings between the parties with respect to such subject matter.

(i) Securities Held by the Company or its subsidiaries. Whenever the consent or approval of holders of a specified percentage of Registrable Securities is required hereunder, Registrable Securities held by the Company or its subsidiaries shall not be counted in determining whether such consent or approval was given by the holders of such required percentage.

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(j) Termination. This Agreement shall terminate when no Registrable Securities remain outstanding; provided that Sections 7 and 8 shall survive any termination hereof.

(k) Specific Performance. The parties hereto recognize and agree that money damages may be insufficient to compensate the holders of any Registrable Securities for breaches by the Company of the terms hereof and, consequently, that the equitable remedy of specific performance of the terms hereof will be available in the event of any such breach.

[signature pages follow]

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IN WITNESS WHEREOF, the parties hereto have caused this Registration Rights Agreement to be duly executed as of the date first above written.

Signature Page to Registration Rights Agreement

EXHIBIT A

ADDENDUM AGREEMENT

This Addendum Agreement is made this      day of             , 20    , by and between                      (the “New Shareholder”) and Continental Resources, Inc. (the “Company”), pursuant to a Registration Rights Agreement dated as of             , 2006 (the “Agreement”), by and among the Company and the Principal Shareholders. Capitalized terms used but not otherwise defined herein shall have the meanings given to such terms in the Agreement.

WITNESSETH:

WHEREAS, the New Shareholder has acquired Registrable Securities directly or indirectly from a Qualified Holder; and

WHEREAS, the Agreement requires that all persons desiring registration rights must enter into an Addendum Agreement binding the New Shareholder to the Agreement to the same extent as if it were an original party thereto;

NOW, THEREFORE, in consideration of the mutual promises of the parties, the New Shareholder acknowledges that it has received and read the Agreement and that the New Shareholder shall be bound by, and shall have the benefit of, all of the terms and conditions set out in the Agreement to the same extent as if it were an original party to the Agreement and shall be deemed to be a Qualified Holder thereunder.

Exhibit A-1

AGREED TO on behalf of the Company pursuant to Section 12(c) of the Agreement.