Columbus Energy S-3ASR Automatic shelf registration

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Exhibit 1.1

$300,000,000

CIMAREX ENERGY CO.

[    ]% Senior Notes due 2017

Underwriting Agreement

        April [    ], 2007

J.P. Morgan Securities Inc.
    As Representative of the
    several Underwriters listed
    in Schedule 1 hereto
c/o J.P. Morgan Securities Inc.
270 Park Avenue
New York, New York 10017

Ladies and Gentlemen:

        Cimarex Energy Co., a Delaware corporation (the "Company"), proposes to issue and sell to the several Underwriters listed in Schedule 1 hereto (the "Underwriters"), for whom you are acting as representative (the "Representative"), $300,000,000 principal amount of its [    ]% Senior Notes due 2017 (the "Securities"). The Securities will be issued pursuant to an Indenture to be dated as of April [    ], 2007 (the "Indenture") among the Company, the subsidiary guarantors listed in Schedule 2 hereto (the "Subsidiary Guarantors") and U.S. Bank National Association, as trustee (the "Trustee"), and will be guaranteed on an unsecured senior basis by each of the Subsidiary Guarantors (the "Guarantees").

        The Company and the Subsidiary Guarantors hereby confirm their agreement with the several Underwriters concerning the purchase and sale of the Securities, as follows:

        1.     Registration Statement. The Company and the Subsidiary Guarantors have 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-[            ]), including a prospectus, relating to the Securities. Such registration statement, as amended at the time it becomes effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness ("Rule 430 Information"), is referred to herein as the "Registration Statement"; and as used herein, the term "Preliminary Prospectus" means each prospectus included in such registration statement (and any amendments thereto) before it becomes effective, any prospectus filed with the Commission pursuant to Rule 424(a) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term "Prospectus" means the prospectus in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Securities. If the Company and the Subsidiary Guarantors have filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the "Rule 462 Registration Statement"), then any reference herein to the term "Registration Statement" shall be deemed to include such Rule 462 Registration Statement. Any reference in this Agreement to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Prospectus, as the case may be and any reference to "amend", "amendment" or "supplement" with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission

thereunder (collectively, the "Exchange Act") that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

        At or prior to the time when sales of the Securities were first made (the "Time of Sale"), the following information shall have been prepared (collectively, the "Time of Sale Information"): the Preliminary Prospectus dated April [    ], 2007, and each "free-writing prospectus" (as defined pursuant to Rule 405 under the Securities Act) listed on Annex B hereto.

        2.     Purchase of the Securities by the Underwriters. (a) The Company agrees to issue and sell the Securities to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective principal amount of Securities set forth opposite such Underwriter's name in Schedule 1 hereto at a price equal to [    ]% of the principal amount thereof plus accrued interest, if any, from April [    ], 2007 to the Closing Date (as defined below). The Company will not be obligated to deliver any of the Securities except upon payment for all the Securities to be purchased as provided herein.

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

        (c)   Payment for and delivery of the Securities will be made at the offices of Simpson Thacher & Bartlett LLP, 425 Lexington Avenue, New York, New York, at 10:00 A.M., New York City time, on April [    ], 2007, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representative and the Company may agree upon in writing. The time and date of such payment and delivery is referred to herein as the "Closing Date".

        (d)   Payment for the Securities shall be made by wire transfer in immediately available funds to the account(s) specified by the Company to the Representative against delivery to the nominee of The Depository Trust Company, for the account of the Underwriters, of one or more global notes representing the Securities (collectively, the "Global Note"), with any transfer taxes payable in connection with the sale of the Securities duly paid by the Company. The Global Note will be made available for inspection by the Representative not later than 1:00 P.M., New York City time, on the business day prior to the Closing Date. The Global Note will have the Guarantees of the Subsidiary Guarantors annexed thereto.

        (e)   The Company and the Subsidiary Guarantors acknowledge and agree that the Underwriters are acting solely in the capacity of an arm's length contractual counterparty to the Company and the Subsidiary Guarantors with respect to the offering of Securities contemplated hereby (including in connection with determining the terms of the offering) and not as financial advisors or fiduciaries to, or agents of, the Company, any Subsidiary Guarantor or any other person. Additionally, neither the Representative nor any other Underwriter is advising the Company, any Subsidiary Guarantor or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company and the Subsidiary Guarantors 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 neither the Representative nor any other Underwriter shall have any responsibility or liability to the Company or the Subsidiary Guarantors with respect thereto. Any review by the Representative or any Underwriter of the Company, the Subsidiary Guarantors and the transactions contemplated hereby or other matters relating to such transactions will be performed solely

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for the benefit of the Representative or such Underwriter and shall not be on behalf of the Company, the Subsidiary Guarantors or any other person.

        3.     Representations and Warranties of the Company and the Subsidiary Guarantors. The Company and the Subsidiary Guarantors, jointly and severally, represent and warrant to each Underwriter that:

        (a)   Preliminary Prospectus. No order preventing or suspending the use of any Preliminary Prospectus has been issued by the Commission, and each Preliminary Prospectus, 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 and the Subsidiary Guarantors make no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in the Preliminary Prospectus.

        (b)   Time of Sale Information. The Time of Sale Information, at the Time of Sale did not, and at the Closing Date 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 and the Subsidiary Guarantors make no representation and warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in such Time of Sale Information. No statement of material fact included in the 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. None of the Company or any Subsidiary Guarantor (including its agents and representatives, other than the Underwriters in their capacity as such) has prepared, made, used, 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 Securities (each such communication by the Company or any Subsidiary Guarantor or their respective agents and representatives (other than a communication referred to in clauses (i), (ii) and (iii) 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, (ii) the Preliminary Prospectus, (iii) the Prospectus, (iv) documents listed on Annex B hereto and (v) any electronic road show or other written communications, in each case approved in writing in advance by the Representative. Each such Issuer Free Writing Prospectus (i) complied in all material respects with the Securities Act, (ii) does not or will not conflict with information contained in the Registration Statement, any Preliminary Prospectus or the Prospectus, (iii) 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 (iv) when taken together with the Preliminary Prospectus filed prior to the first use of such Issuer Free Writing Prospectus and any other Issuer Free Writing Prospectus, did not, and at the Closing Date 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 and the Subsidiary Guarantors make no representation and warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in any Issuer Free Writing Prospectus.

        (d)   Registration Statement and 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

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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 Securities has been initiated or threatened by the Commission; as of the applicable effective date of the Registration Statement and any amendment thereto, the Registration Statement complied and will comply in all material respects with the Securities Act and the Trust Indenture Act of 1939, as amended, and the rules and regulations of the Commission thereunder (collectively, the "Trust Indenture 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, 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 and the Subsidiary Guarantors make no representation and warranty with respect to (i) that part of the Registration Statement that constitutes the Statement of Eligibility and Qualification (Form T-1) of the Trustee under the Trust Indenture Act or (ii) any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto.

        (e)   Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Prospectus and the Time of Sale Information, 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 required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the Registration Statement, the Prospectus or the Time of Sale Information, when such documents become effective or are filed with the Commission, as the case may be, will conform in all material respects to the requirements of the Securities Act or the Exchange Act, as applicable, and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

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

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information are reasonable and are 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, (i) there has not been any change in the capital stock or long-term debt of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock except, as of March 31, 2007, (A) pursuant to the exercise of 403,250 options or warrants or pursuant to issuance of common stock under the Company's stock incentive plans, (B) the purchase of 6,987 shares of common stock by the Company and (C) the borrowing of approximately $66 million aggregate principal amount under the Company's senior secured revolving credit facilities, with no material issuances of common stock or borrowings since March 31, 2007, or any material adverse change, or any development involving a prospective material adverse change, in or affecting the business, properties, management, financial position, results of operations of the Company and its subsidiaries taken as a whole; and (ii) neither the Company nor any of its subsidiaries 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, except in each case as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus.

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

        (i)    Capitalization. All the outstanding shares of capital stock or other equity interests of each subsidiary of the Company have been duly and validly authorized and issued, are fully paid and non-assessable (except as otherwise described in the Registration Statement, the Time of Sale Information and the Prospectus) and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party (except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus).

        (j)    Due Authorization. The Company and each Subsidiary Guarantor has full right, power and authority to execute and deliver this Agreement, the Securities and the Indenture (including each Guarantee set forth therein) (collectively, the "Transaction Documents") and to perform its respective obligations hereunder and thereunder; and all action required to be taken for the due and proper authorization, execution and delivery of each of the Transaction Documents and the consummation of the transactions contemplated thereby has been duly and validly taken.

        (k)   The Indenture. The Indenture has been duly authorized by the Company and each of the Subsidiary Guarantors and has been duly qualified under the Trust Indenture Act and, when duly executed and delivered in accordance with its terms by each of the parties thereto, will constitute a valid and legally binding agreement of the Company and each of the Subsidiary Guarantors enforceable against the Company and each of the Subsidiary Guarantors in accordance with its terms, except as

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enforceability may be limited by applicable bankruptcy, insolvency or similar laws affecting the enforcement of creditors' rights generally or by equitable principles relating to enforceability, regardless of whether such enforceability is considered in a proceeding at law or in equity (collectively, the "Enforceability Exceptions").

        (l)    The Securities. The Securities have been duly authorized by the Company and, when duly executed, authenticated, issued and delivered as provided in the Indenture and paid for as provided herein, will be duly and validly issued and outstanding and will constitute valid and legally binding obligations of the Company enforceable against the Company in accordance with their terms, subject to the Enforceability Exceptions, and will be entitled to the benefits of the Indenture.

        (m)  The Guarantees. The Guarantees have been duly authorized by each of the Subsidiary Guarantors and, when duly executed, authenticated, issued and delivered as provided in the Indenture and paid for as provided herein, will be valid and legally binding obligations of each of the Subsidiary Guarantors enforceable against each of the Subsidiary Guarantors in accordance with their terms, subject to the Enforceability Exceptions, and will be entitled to the benefits of the Indenture.

        (n)   Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company and each of the Subsidiary Guarantors.

        (o)   Descriptions of the Transaction Documents. Each Transaction Document conforms in all material respects to the description thereof contained in the Registration Statement, the Time of Sale Information and the Prospectus.

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

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

        (r)   No Consents Required. No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority (including without limitation

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the Federal Energy Regulatory Commission) is required for the execution, delivery and performance by the Company and each of the Subsidiary Guarantors of each of the Transaction Documents to which it is a party, the issuance and sale of the Securities, the execution and delivery of the Guarantees and compliance by the Company and the Subsidiary Guarantors with the terms thereof and the consummation of the transactions contemplated by the Transaction Documents, except for the registration of the Securities and the Guarantees under the Securities Act, the qualification of the Indenture under the Trust Indenture Act and such consents, approvals, authorizations, orders and registrations or qualifications as may be required under applicable state securities laws in connection with the purchase and distribution of the Securities by the Underwriters.

        (s)   Legal Proceedings. Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, there are no actions, suits or proceedings pending or legal, governmental or regulatory investigations to which the Company or any of its subsidiaries is a party or, to the Company's knowledge, to which any property of the Company or any of its subsidiaries is the subject that, if determined adversely to the Company or any of its subsidiaries, would have a Material Adverse Effect; no such investigations, actions, suits or proceedings are threatened (which threat has been communicated to the Company or such subsidiary) or, to the Company's knowledge, contemplated by any governmental or regulatory authority or by others.

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

        (u)   Title to Real and Personal Property. Except as described in the Registration Statement, the Time of Sale Information and the Prospectus, the Company and its subsidiaries have good and indefeasible title in fee simple to all items of real property, and good title to all items of personal property, or in either case have valid rights to lease or otherwise use, all items of such real or personal property that are material to the respective businesses of the Company and its subsidiaries, in each case free and clear of all liens, encumbrances, claims and defects and imperfections of title except those that (i) do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries or (ii) would not have a Material Adverse Effect.

        (v)   Title to Intellectual Property. The Company and its subsidiaries own or possess adequate rights to use all material patents, patent applications, trademarks, service marks, trade names, trademark registrations, service mark registrations, copyrights, licenses and know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures) necessary for the conduct of their respective businesses; and the conduct of their respective businesses will not conflict in any respect with any such rights of others, and the Company and its subsidiaries have not received any notice of any claim of infringement or conflict with any such rights of others, except as in each case would not have a Material Adverse Effect.

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

        (x)   Investment Company Act. Neither the Company nor any of the Subsidiary Guarantors is and, after giving effect to the offering and sale of the Securities and the application of the proceeds thereof as described in the Registration Statement, the Time of Sale Information and the Prospectus, none of them will be an "investment company" or an entity "controlled" by an "investment company" within

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the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder (collectively, the "Investment Company Act").

        (y)   Taxes. The Company and its subsidiaries have filed all material tax returns required to be filed through the date hereof and have paid all taxes due thereon except those being contested in good faith, those for which reserves have been provided in accordance with GAAP or those currently payable without penalty or interest; and except as otherwise disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, there is no tax deficiency that has been, or could reasonably be expected to be, determined adversely against the Company or any of its subsidiaries or any of their respective properties or assets which would have a Material Adverse Effect.

        (z)   Licenses and Permits. The Company and its subsidiaries 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, neither the Company nor any of its subsidiaries 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, except for such licenses, certificates, permits and other authorizations which would have a Material Adverse Effect.

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

        (bb) Compliance With Environmental Laws. Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, (i) the Company and its subsidiaries (x) are, and, to the knowledge of the Company, at all prior times were, in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, requirements, decisions and orders relating to the protection of human health or safety, the environment, natural resources, 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 to conduct their respective businesses; and (z) have not received written notice of any actual or potential liability under or relating to any Environmental Laws, including for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, and (ii) there are no liabilities associated with Environmental Laws of or relating to the Company or its subsidiaries, except in the case of each of (i) and (ii) above, for any such failure to comply, or failure to receive required permits, licenses or approvals, or liability, as would not, individually or in the aggregate, have a Material Adverse Effect; and (iii) except as described in the Time of Sale Information and Prospectus, (x) there are no proceedings that are pending, or that are known by the Company to be contemplated, against the Company or any of its subsidiaries under any Environmental Laws in which a governmental entity is also a party, other than such proceedings regarding which it is reasonably believed no monetary sanctions of $100,000 or more will be imposed and (y) the Company does not anticipate that it or any of its subsidiaries will make capital expenditures relating to any Environmental Laws as would, individually or in the aggregate, have a Material Adverse Effect.

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        (cc)   Compliance With ERISA. (i) Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended ("ERISA"), for which the Company or any member of its "Controlled group" (defined as any organization which is a member of a controlled group of corporations within the meaning of Section 414 of the Internal Revenue Code of 1986, as amended (the "Code")) would have any liability (each, a "Plan") has been maintained in material compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including but not limited to ERISA and the Code; (ii) other than one transaction that has been fully corrected, no prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any Plan excluding transactions effected pursuant to a statutory or administrative exemption; (iii) for each Plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no "accumulated funding deficiency" as defined in Section 412 of the Code, whether or not waived, has occurred or is reasonably expected to occur; (iv) the fair market value of the assets of each Plan exceeds the present value of all benefits accrued under such Plan (determined based on those assumptions used to fund such Plan); (v) no "reportable event" (within the meaning of Section 4043(c) of ERISA) has occurred or is reasonably expected to occur; and (vi) neither the Company nor any member of the Controlled Group has incurred, nor reasonably expects to incur, any liability under Title IV of ERISA (other than contributions to the Plan or premiums to the PBGC, in the ordinary course and without default) in respect of a Plan (including a "multiemployer plan", within the meaning of Section 4001(a)(3) of ERISA).

        (dd)   Disclosure Controls. The Company and its subsidiaries maintain an effective system of "disclosure controls and procedures" (as defined in Rule 13a-15(e) of the Exchange Act) that 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 ensure that such information is accumulated and communicated to the Company's management as appropriate to allow timely decisions regarding required disclosure. The Company and its subsidiaries have carried out evaluations of the effectiveness of their disclosure controls and procedures as required by Rule 13a-15 of the Exchange Act.

        (ee)   Accounting Controls. The Company and its subsidiaries maintain systems of "internal control over financial reporting" (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of, their respective principal executive and principal financial officers, or persons performing similar functions, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles, including, but not limited to internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management's authorization; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management's authorization; and (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as disclosed in the Registration Statement, the Time of Sale Information and the Prospectus, there are no material weaknesses in the Company's internal controls.

        (ff)    Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses in such amounts and covering such losses and risks as are adequate to protect the Company and its subsidiaries and their respective businesses; and neither the Company nor any of its subsidiaries has (i) received notice from any insurer or agent of such insurer that capital 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

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as and when such coverage expires or to obtain similar coverage at reasonable cost from similar insurers.

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

        (hh)   Solvency. On and immediately after the Closing Date, the Company (after giving effect to the issuance of the Securities and the other transactions related thereto as described in the Registration Statement, the Time of Sale Information and the Prospectus) will be Solvent. As used in this paragraph, the term "Solvent" means, with respect to a particular date, that on such date (i) the present fair market value (or present fair saleable value) of the assets of the Company is not less than the total amount required to pay the liabilities of the Company on its total existing debts and liabilities (including contingent liabilities) as they become absolute and matured; (ii) the Company is able to realize upon its assets and pay its debts and other liabilities, contingent obligations and commitments as they mature and become due in the normal course of business; (iii) assuming consummation of the issuance of the Securities as contemplated by this Agreement, the Registration Statement, the Time of Sale Information and the Prospectus, the Company is not incurring debts or liabilities beyond its ability to pay as such debts and liabilities mature; and (iv) the Company is not engaged in any business or transaction, and does not propose to engage in any business or transaction, for which its property would constitute unreasonably small capital after giving due consideration to the prevailing practice in the industry in which the Company is engaged.

        (ii)     No Restrictions on Subsidiaries. Except as provided for in the senior secured revolving credit facilities and the indenture governing the 2012 Notes, no subsidiary of the Company is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary's capital stock, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary's properties or assets to the Company or any other subsidiary of the Company.

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

        (kk)   No Stabilization. Neither the Company nor any Subsidiary Guarantor has 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 Securities.

        (ll)     Margin Rules. Neither the issuance, sale and delivery of the Securities nor the application of the proceeds thereof by the Company as described in the Registration Statement, the Time of Sale Information and the Prospectus will violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

        (mm)   Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included or incorporated by reference 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.

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

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

        (pp)   Reserve Report Data. The oil and gas reserve estimates of the Company and its subsidiaries for the fiscal years ended December 31, 2006, 2005 and 2004 contained in the Registration Statement, the Time of Sale Information and the Prospectus are derived from the books and records of the Company and its subsidiaries, with respect to which the petroleum engineering firms have reviewed the proved reserve estimates associated with at least 80% of the discounted future net cash flows before income taxes for such years, all as set forth in the reports prepared by the petroleum engineering firms; and such reserve estimates fairly reflect, in all material respects, the oil and gas reserves of the Company and its subsidiaries at the dates indicated therein and are in accordance with the Commission guidelines applicable thereto applied on a consistent basis throughout the periods involved.

        (qq)   Independent Reserve Engineering Firms. Ryder Scott Company, L.P. and DeGolyer and MacNaughton who have certified the oil and gas reserve estimates of the Company and its subsidiaries, are each an independent reserve engineer with respect to the Company for the periods set forth in the Registration Statement, the Time of Sale Information and the Prospectus.

        (rr)    Public Utility Holding Company Act/Federal Power Act. Neither the Company nor any of its subsidiaries is subject to regulation as a "public utility company", "holding company" (or similar designation) or a "subsidiary company" of a holding company or an "affiliate" thereof by any governmental or regulatory authority, including under the Public Utility Holding Company Act of 2005 or the Federal Power Act, as amended, or any applicable state utility laws.

        4.     Further Agreements of the Company and the Subsidiary Guarantors. The Company and each of the Subsidiary Guarantors, jointly and severally, covenants and agrees with each Underwriter that:

        (a)   Required Filings. The Company and the Subsidiary Guarantors 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 (including the Term Sheet in the form of Annex C hereto) to the extent required by Rule 433 under the Securities Act; and will file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Securities; and the Company 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 Representative may reasonably request. The Company will pay the registration fees for the offering of the Securities within the time period required by Rule 456(b)(1)(i) 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 Representative, two signed copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and documents incorporated by reference therein; and (ii) to each Underwriter (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith

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(except to the extent available on the Commission's EDGAR Website) and (B) during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein) and each Issuer Free Writing Prospectus as the Representative 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 Securities as in the opinion of counsel for the Underwriters a prospectus relating to the Securities 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 Securities by any Underwriter or dealer.

        (c)   Amendments or Supplements; Issuer Free Writing Prospectuses. Before making, 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 Representative and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not make, 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 Representative reasonably objects.

        (d)   Notice to the Representative. The Company will advise the Representative promptly, and confirm such advice in writing, (i) when the Registration Statement has become effective; (ii) when any amendment to the Registration Statement has been filed or becomes effective; (iii) when any supplement to the Prospectus or any amendment to the Prospectus or any Issuer Free Writing Prospectus has been filed; (iv) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (v) of the issuance by the Commission of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus or the Prospectus or the initiation or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (vi) of the occurrence of any event within the Prospectus Delivery Period as a result of which the Prospectus, the 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; (vii) 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 (viii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Securities for offer and sale in any jurisdiction or the initiation or threatening of any proceeding for such purpose; and the Company will use its reasonable 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 Securities and, if any such order is issued, will obtain as soon as possible the withdrawal thereof.

        (e)   Time of Sale Information. If at any time prior to the Closing Date (i) any event shall occur or condition shall exist as a result of which the Time of Sale Information as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary in order to 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 Section 4(c) hereof, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representative may designate, such amendments or supplements to the Time of Sale Information as may be necessary so that the statements in the Time of Sale Information as so

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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)    Ongoing Compliance. If during the Prospectus Delivery Period (i) any event shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact 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 Section 4(c) hereof, file with the Commission and furnish to the Underwriters and to such dealers as the Representative 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.

        (g)   Blue Sky Compliance. The Company will qualify the Securities for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Representative shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Securities;provided that neither the Company nor any of the Subsidiary Guarantors shall 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.

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

        (i)    Clear Market. During the period from the date hereof through and including the date that is 90 days after the date hereof, the Company and each of the Subsidiary Guarantors will not, without the prior written consent of the Representative, offer, sell, contract to sell or otherwise dispose of any debt securities issued or guaranteed by the Company or any of the Subsidiary Guarantors and having a tenor of more than one year.

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

        (k)   No Stabilization. Neither the Company nor any of the Subsidiary Guarantors will 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 Securities.

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

        5.     Certain Representations and 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 or any Subsidiary Guarantor and not incorporated by reference into the Registration Statement and any press release issued by the Company or any Subsidiary Guarantor) other than (i) a free writing prospectus that, solely as a result

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of use by such Underwriter, would not trigger an obligation to file such free writing prospectus with the Commission pursuant to Rule 433, (ii) any Issuer Free Writing Prospectus listed on Annex B or prepared pursuant to Section 3(c) or Section 4(c) hereof (including any electronic roadshow), 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"). Notwithstanding the foregoing, the Underwriters may use a term sheet substantially in the form of Annex C hereto without the consent of the Company.

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

        6.     Conditions of Underwriters' Obligations. The obligation of each Underwriter to purchase Securities on the Closing Date as provided herein is subject to the performance by the Company and each of the Subsidiary Guarantors 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 a Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 4(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Representative.

        (b)   Representations and Warranties. The representations and warranties of the Company and the Subsidiary Guarantors contained herein shall be true and correct on the date hereof and on and as of the Closing Date; and the statements of the Company and the Subsidiary Guarantors and their respective officers made in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date.

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

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

        (e)   Officers' Certificate. The Representative shall have received on and as of the Closing Date a certificate of two executive officers of the Company and of each Subsidiary Guarantor who have specific knowledge of the Company's or such Subsidiary Guarantor's financial matters and are satisfactory to the Representative (i) confirming that such officers have carefully reviewed the

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Registration Statement, the Time of Sale Information and the Prospectus and, to the knowledge of such officers, the representations set forth in Sections 3(b) and 3(d) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company and the Subsidiary Guarantors in this Agreement are true and correct and that the Company and the Subsidiary Guarantors have complied with all agreements and satisfied all conditions on their part to be performed or satisfied hereunder at or prior to the Closing Date and (iii) to the effect set forth in Sections 6(a), 6(c) and 6(d) hereof.

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

        (g)   Opinion and 10b-5 Statement of Counsel for the Company and the Subsidiary Guarantors. Holme Roberts & Owen LLP, counsel for the Company and the Subsidiary Guarantors, shall have furnished to the Representative, at the request of the Company, their written opinion and 10b-5 Statement, dated the Closing Date and addressed to the Underwriters, in the form set forth in Annex A hereto.

        (h)   Opinion and 10b-5 Statement of Counsel for the Underwriters. The Representative shall have received on and as of the Closing Date an opinion and 10b-5 Statement of Simpson Thacher & Bartlett LLP, counsel for the Underwriters, with respect to such matters as the Representative may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

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

        (j)    Good Standing. The Representative shall have received on the Closing Date satisfactory evidence of the good standing of the Company and the Subsidiary Guarantors in their respective jurisdictions of organization and their good standing in such other jurisdictions as the Representative may reasonably request, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions dated as of a date reasonably acceptable to the Representative.

        (k)   Reserve Report Confirmation Letters. On the date of this Agreement and on the Closing Date, Ryder Scott Company, L.P. and DeGolyer and MacNaughton shall have furnished to the Representative, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representative, containing statements and information with respect to the estimated oil and gas reserves of the Company and its subsidiaries as reported in letters to the Company.

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

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        (m)  Call Notice. The Company shall issue a call notice (the "Call Notice") for all of its outstanding 9.60% Senior Notes due March 15, 2012 (the "2012 Notes") within 1 business day of the date of this Agreement.

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

        7.     Indemnification and Contribution.

        (a)   Indemnification of the Underwriters. The Company and each of the Subsidiary Guarantors, jointly and severally, agree to indemnify and hold harmless each Underwriter, its affiliates, directors and officers and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, legal fees and other expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading, (ii) or any untrue statement or alleged untrue statement of a material fact contained in the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information, or caused by any omission or alleged omission to state therein a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading, in each case except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use therein.

        (b)   Indemnification of the Company and the Subsidiary Guarantors. Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, each of the Subsidiary Guarantors, each of their respective directors, each of their respective officers who signed the Registration Statement and each person, if any, who controls the Company or any of the Subsidiary Guarantors within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act to the same extent as the indemnity set forth in Section 7(a) above, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representative expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus or any Time of Sale Information, it being understood and agreed that the only such information consists of the following information in the Preliminary Prospectus and the Prospectus: (i) the third paragraph under the caption "Underwriting", which paragraph relates to selling arrangements; (ii) third and fourth sentences of the fifth paragraph under the caption "Underwriting" in the Prospectus, which sentences relate to market-making; and (iii) the sixth paragraph under the caption "Underwriting," which paragraph relates to stabilizing transactions.

        (c)   Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either Section 7(a) or 7(b) above, such person (the "Indemnified Person") shall promptly notify the person against whom such indemnification may be sought (the "Indemnifying Person") in writing;providedthat the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under Section 7(a) or 7(b) except to the

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extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; andprovided,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 Section 7(a) or 7(b). 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 and any others entitled to indemnification pursuant to Section 7 that the Indemnifying Party may designate in such proceeding and shall pay the fees and expenses of counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. 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 reimbursed as they are incurred. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by J.P. Morgan Securities Inc. and any such separate firm for the Company, the Subsidiary Guarantors, their respective directors, their respective officers who signed the Registration Statement and any control persons of the Company or any of the Subsidiary Guarantors shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there is a final judgment for the plaintiff, the Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

        (d)   Contribution. If the indemnification provided for in Sections 7(a) and 7(b) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company and the Subsidiary Guarantors on the one hand and the Underwriters on the other from the offering of the Securities or (ii) if the allocation

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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 Subsidiary Guarantors 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 Subsidiary Guarantors on the one hand and the Underwriters on the other shall be deemed to be in the respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Securities 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 Securities. The relative fault of the Company and the Subsidiary Guarantors on the one hand and the Underwriters on the other shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or any Subsidiary Guarantor or by the Underwriters and the parties' relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

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

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

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

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

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

        (b)   If, after giving effect to any arrangements for the purchase of the Securities of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in Section 10(a) above, the aggregate principal amount of such Securities that remains unpurchased does not exceed one-eleventh of the aggregate principal amount of all the Securities, then the Company shall have the right to require each non-defaulting Underwriter to purchase the principal amount of Securities that such Underwriter agreed to purchase hereunder plus such Underwriter'spro ratashare (based on the principal amount of Securities that such Underwriter agreed to purchase hereunder) of the Securities of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

        (c)   If, after giving effect to any arrangements for the purchase of the Securities of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters and the Company as provided in Section 10(a) above, the aggregate principal amount of such Securities that remains unpurchased exceeds one-eleventh of the aggregate principal amount of all the Securities, or if the Company shall not exercise the right described in Section 10(b) above, then this Agreement shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 10 shall be without liability on the part of the Company or the Subsidiary Guarantors, except that the Company and each of the Subsidiary Guarantors will continue to be liable for the payment of expenses as set forth in Section 11 hereof and except that the provisions of Section 7 hereof shall not terminate and shall remain in effect.

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

        11.   Payment of Expenses. (a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company and each of the Subsidiary Guarantors will, jointly and severally, 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 Securities 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 each of the Transaction Documents; (iv) the fees and expenses of counsel for the Company and the Subsidiary Guarantors;

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(v) the fees and expenses of the Company's independent accountants; (vi) the fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Securities under the laws of such jurisdictions as the Representative may designate and the preparation, printing and distribution of a Blue Sky Memorandum (including the related fees and expenses of counsel for the Underwriters); (vii) any fees charged by rating agencies for rating the Securities; (viii) the fees and expenses of the Trustee and any paying agent (including related fees and expenses of any counsel to such parties); (ix) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, the National Association of Securities Dealers, Inc.; and (x) all expenses incurred by the Company in connection with any "road show" presentation to potential investors; provided, that except as provided in Section 7 and this Section 11, the Underwriters shall pay their own costs and expenses, including the costs and expenses of their counsel, any transfer taxes on the Securities that they sell and the expenses of advertising any offering of the Securities made by the Underwriters.

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

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

        13.   Survival. The respective indemnities, rights of contribution, representations, warranties and agreements of the Company, the Subsidiary Guarantors and the Underwriters contained in this Agreement or made by or on behalf of the Company, the Subsidiary Guarantors or the Underwriters pursuant to this Agreement or any certificate delivered pursuant hereto shall survive the delivery of and payment for the Securities 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 Subsidiary Guarantors or the Underwriters.

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

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

        (b)   Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to the Representative c/o J.P. Morgan Securities Inc., 270 Park Avenue, New York, New York 10017 (fax: 212-270-1063); Attention: Lawrence Landry. Notices to the Company and the Subsidiary Guarantors shall be given to them at 1700 Lincoln Street, Suite 1800, Denver, Colorado 80203 (fax: 303-295-3494); Attention: Chief Financial Officer, with

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a copy to Thomas A. Richardson, Holme Roberts & Owen LLP, 1700 Lincoln Street, Suite 4100, Denver, Colorado 80203-4541.

        (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.

Very truly yours,
CIMAREX ENERGY CO.
By:	Name: Title:
GUARANTORS:
BROCK GAS SYSTEMS & EQUIPMENT, INC.
By:	Name: Title:
CIMAREX CALIFORNIA PIPELINE LLC
By:	Name: Title:
CIMAREX ENERGY CO. OF COLORADO
By:	Name: Title:
CIMAREX TEXAS LLC
By:	Name: Title:
CIMAREX TEXAS L.P.
By:	Name: Title:

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COLUMBUS ENERGY CORP.
By:	Name: Title:
COLUMBUS ENERGY L.P.
By:	Name: Title:
COLUMBUS GAS SERVICES, INC.
By:	Name: Title:
COLUMBUS TEXAS, INC.
By:	Name: Title:
CONMAG ENERGY CORPORATION
By:	Name: Title:
HUNTER GAS GATHERING, INC.
By:	Name: Title:
KEY PRODUCTION COMPANY, INC.
By:	Name: Title:

23

KEY PRODUCTION TEXAS L.P.
By:	Name: Title:
KEY TEXAS LLC
By:	Name: Title:
MAGNUM HUNTER PRODUCTION, INC.
By:	Name: Title:
OKLAHOMA GAS PROCESSING, INC.
By:	Name: Title:
PEC (DELAWARE), INC.
By:	Name: Title:
PINTAIL ENERGY, INC.
By:	Name: Title:
PRIZE ENERGY RESOURCES, L.P.
By:	Name: Title:

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PRIZE OPERATING COMPANY
By:	Name: Title:
TRAPMAR PROPERTIES, INC.
By:	Name: Title:

Accepted: April [    ], 2007
J.P. MORGAN SECURITIES INC.
For itself and on behalf of the several Underwriters listed in Schedule 1 hereto.
By	Authorized Signatory

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Schedule 1

Underwriter		Principal Amount
J.P. Morgan Securities Inc.		$
Lehman Brothers Inc.
Deutsche Bank Securities Inc.
Merrill Lynch, Pierce, Fenner & Smith                       Incorporated
Calyon Securities (USA) Inc.
Raymond James & Associates, Inc.
UBS Securities LLC
	Total	$	300,000,000

Schedule 2

LIST OF SUBSIDIARY GUARANTORS

Brock Gas Systems & Equipment, Inc.
Cimarex California Pipeline LLC
Cimarex Energy Co. of Colorado
Cimarex Texas LLC
Cimarex Texas L.P.
Columbus Energy Corp.
Columbus Energy L.P.
Columbus Gas Services, Inc.
Columbus Texas, Inc.
Conmag Energy Corporation
Hunter Gas Gathering, Inc.
Key Production Company, Inc.
Key Production Texas, L.P.
Key Texas LLC
Magnum Hunter Production, Inc.
Oklahoma Gas Processing, Inc.
PEC (Delaware), Inc.
Pintail Energy, Inc.
Prize Energy Resources, L.P.
Prize Operating Company
Trapmar Properties, Inc.

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$300,000,000 CIMAREX ENERGY CO. [ ]% Senior Notes due 2017 Underwriting Agreement
LIST OF SUBSIDIARY GUARANTORS