Exhibit 2.1

PURCHASE AND SALE AGREEMENT

This Purchase and Sale Agreement (this “Agreement”) is made and entered into this 28th day of November 2007, by and between Ambrose Energy I, Ltd., a Texas limited partnership, and each of the other persons, which are listed as a party Seller on the signature pages and which execute a counterpart of this Agreement, ( all of the foregoing described parties are referred to collectively as “Seller” or “Parties Seller” and individually as a “Party Seller,”), and Windsor Permian LLC, a Delaware limited liability company (“Buyer”). Buyer and Seller are collectively referred to herein as the “Parties”, and are sometimes referred to individually as a “Party.”

W I T N E S S E T H:

WHEREAS, Seller is willing to sell to Buyer, and Buyer is willing to purchase from Seller, all of Seller’s right, title, and interest in and to the Assets, all upon the terms and conditions hereinafter set forth:

NOW, THEREFORE, in consideration of the mutual benefits derived and to be derived from this Agreement by each party, Seller and Buyer hereby agree as follows:

ARTICLE I

Assets

Section 1.01 Agreement to Sell and Purchase. Subject to and in accordance with the terms and conditions of this Agreement, Seller agrees to sell and Buyer agrees to purchase the Assets from Seller.

Section 1.02 Assets. Subject to Section 1.03, the term “Assets” shall mean all of Seller’s right, title and interest in and to the following:

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Section 1.03 Excluded Assets. Notwithstanding the foregoing, the Assets shall not include, and there is excepted, reserved, and excluded from the sale, transfer, and assignment contemplated hereby the following (collectively, the “Excluded Assets”): (a) all trade credits and all accounts, accounts receivable, checks, funds, promissory notes, instruments and general intangibles (as such terms are defined in the Texas Uniform Commercial Code) attributable to the Assets with respect to any period of time prior to the Effective Time; (b) all claims and causes of action of Seller (i) arising from acts, omissions or events, or damage to or destruction of property, occurring prior to the Effective Time, (ii) arising under or with respect to any of the Contracts that are attributable to periods of time prior to the Effective Time (including claims for adjustments or refunds), or (iii) with respect to any of the other Excluded Assets; (c) all rights and interests of Seller (i) under any policy or agreement of insurance or indemnity, (ii) under any bond, or (iii) to any insurance or condemnation proceeds or awards arising, in each case, from acts, omissions or events, or damage to or destruction of property, occurring prior to the Effective Time; (d) all Hydrocarbons produced from or attributable to the Subject Interests with respect to all periods prior to the Effective Time, together with all proceeds from the sale of such Hydrocarbons; (e) all claims of Seller for refunds of or loss carry forwards with respect to (i) ad valorem, severance, production or any other taxes attributable to any period prior to the Effective Time, (ii) income, margin or franchise taxes, or (iii) any taxes attributable to the other Excluded Assets, and such other refunds, and rights thereto, for amounts paid in connection with the Assets and attributable to the period prior to the Effective Time, including refunds of amounts paid under any gas gathering or transportation agreement; (f) all amounts due or payable to Seller as adjustments to insurance premiums related to the Assets with respect to any period prior to the Effective Time; (g) all proceeds, income or revenues (and any security or other deposits made) attributable to (i) the Assets for any period prior to the Effective Time, or (ii) any other Excluded Assets; (h) all vehicles, personal computers and associated peripherals and all radio, telephone and other communication equipment; (i) all of Seller’s proprietary computer software, technology, patents, trade secrets, copyrights, names, trademarks, logos and other intellectual property; (j) all of Seller’s rights and interests in geological and geophysical data that cannot be transferred without the consent of, or payment to, any third party; (k) all documents and instruments of Seller that may be protected by an attorney-client privilege; (l) data and other information that cannot be disclosed or assigned to Buyer as a result of confidentiality or similar arrangements under agreements with persons unaffiliated with Seller; (m) all audit rights arising under any of the Contracts or otherwise with respect to any period prior to the Effective Time; (n) deleted; (o) all corporate, partnership, income tax and financial records of Seller; (p) all (i)

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agreements and correspondence between Seller and any advisor of Seller (the “Advisor”) relating to the transactions contemplated in this Agreement, (ii) lists of prospective purchasers for such transactions compiled by either Seller or the Advisor, (iii) bids submitted by other prospective purchasers of the Assets, (iv) analyses by Seller or the Advisor of any bids submitted by any prospective purchaser, (v) correspondence between or among Seller or Advisor, or either of their respective representatives, and any prospective purchaser other than Buyer, and (vi) correspondence between Seller or Advisor or any of their respective representatives with respect to any of the bids, the prospective purchasers, the engagement or activities of the Advisor, or the transactions contemplated in this Agreement; and (q) all of Duncan Chisholm’s and/or Ironwood Exploration LLC’s rights and interests in all seismic and geophysical data and information related to the Owens Area 3-D Seismic Project and acquired pursuant to that certain Letter Agreement dated July 14, 2000, among John L. Cox, Douglas H. Christensen and Duncan Chisholm.

ARTICLE II

Purchase Price

Section 2.01 Purchase Price. The total consideration for the purchase, sale, and conveyance of the Assets to Buyer is Buyer’s payment to Seller of the sum of One Hundred Seventy Million and No/100’s Dollars ($170,000,000.00) (the “Purchase Price”), as adjusted in accordance with the provisions of this Agreement; and the assumption of the Assumed Obligations.

Section 2.02 Allocated Value(s). The Purchase Price is allocated among the Assets by Buyer, as set forth in Exhibit F (the “Allocated Value(s)”). Seller and Buyer agree that the Allocated Value(s) shall be used to compute any adjustments to the Purchase Price pursuant to the provisions of Article IV. Any subsequent adjustments to the Purchase Price hereunder shall be reflected in the allocation hereunder consistent with Treasury Regulation § 1.1060-IT(f). For tax purposes, the Parties agree to report the transactions contemplated by this Agreement in a manner consistent with the terms of this Agreement, including the allocations set forth above as of the Closing Date, and that neither Party will take any position inconsistent therewith, including in any tax return, in any refund claim, in any litigation or arbitration or otherwise.

Section 2.03 Earnest Money Deposit. Concurrently with the execution of this Agreement by Buyer and Seller, Buyer shall deposit with Seller, by wire transfer of immediately available funds to an account designated by Seller, 10% of the Purchase Price or Seventeen Million Dollars ($17,000,000.00) as an earnest money deposit (the “Earnest Money Deposit”) to assure Buyer’s performance of its obligations under this Agreement. If Closing occurs, the Earnest Money Deposit, together with interest earned thereon, will be applied to the Adjusted Purchase Price. If Closing fails to occur, the Earnest Money Deposit shall be handled in accordance with Section 16.02 hereof.

Section 2.04 1031 Exchange. Seller, in lieu of the sale of the Assets to Buyer for the cash consideration provided herein, shall have the right at any time prior to Closing to assign all or a portion of its rights under this Agreement to a qualified intermediary, in order to accomplish the transaction in a manner that will comply, either in whole or in part with the requirements of a

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like-kind exchange pursuant to §1031 of the Internal Revenue Code of 1986, as amended. In the event Seller does assign its rights under this Agreement pursuant to this Article 2.04, Seller agrees to notify Buyer in writing of such assignment not less than seven (7) days before Closing. If Seller assigns its rights under this Agreement, Buyer agrees to (i) consent to Seller’s assignment of its rights in this Agreement, and (ii) deposit at Closing with the qualified escrow or qualified trust account the Purchase Price, as adjusted pursuant to this Agreement, i.e. subject to the Purchase Price Adjustments on the Pre-Closing Statement, in immediately available funds pursuant to wire transfer instructions to be provided by Seller to Buyer, before the Closing Date. Seller indemnifies Buyer for any cost, claim or liability arising from any assignment by Seller pursuant to the provisions of this Section.

ARTICLE III

Effective Time

If the transactions contemplated hereby are consummated in accordance with the terms and provisions hereof, the ownership of the Assets shall be transferred from Seller to Buyer on the Closing Date, but effective for all purposes as of 7:00 a.m. local time at the location of the Assets on November 1, 2007 (the “Effective Time”), which shall be consummated by assignments in the forms of the Assignment, Bill of Sale, and Conveyance attached hereto as Exhibit G, (the “Assignments”), containing a special warranty of title from Seller to Buyer as to the Leases and Wells being conveyed thereby in the form stated therein, subject to Permitted Encumbrances and the terms of this Agreement. Buyer shall be entitled to be paid, or credited for, any and all revenues or other amounts realized from or accruing to the Assets subsequent to the Effective Time and shall be responsible for all expenses for the development and operation of the Assets subsequent to the Effective Time. Seller shall be entitled to retain any and all revenues and other amounts realized from and accruing to the Assets prior to the Effective time, and shall be responsible for all expenses for the development and operations of the Assets incurred prior to the Effective Time.

ARTICLE IV

Title and Environmental Matters

Section 4.01 Examination Period.

After the execution of this Agreement until 5:00 p.m., local time in Midland, Texas on December 7, 2007 (the “Examination Period”), at Buyer’s sole cost and risk, Seller

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Section 4.02 Title Matters.

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Section 4.03 Title Review. At its sole cost and expense, Buyer shall commence and diligently pursue such examination of title to the Assets as Buyer desires and may continue such examination through the Closing Date, as defined in Section 10.01, below.

Section 4.04 Determination of Title Defects and the Defect Values.

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Any Title Defect that is not identified in the Title Defect Notice shall thereafter be forever waived and expressly assumed by Buyer, except for any Title Defect that constitutes a breach of Seller’s special warranty of title contained in the form of Assignment attached hereto as Exhibit G. Closing shall occur notwithstanding the Title Defects identified by Buyer, subject to Section 10.03.

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Section 4.05 Suspense Funds Held by Seller. Seller agrees to convey to Buyer and Buyer agrees to receive all suspense held by Seller, if any, as of the Effective Time, for the benefit of royalty, overriding royalty and working interest owners attributable to the Leases or Wells, except and excluding minimum suspense funds and suspense accounts with a negative balance, the amount of such funds to be adjusted with respect to the suspense funds received and disbursed by Seller. Buyer will defend, indemnify and hold Seller harmless from and against any future liability associated with such funds.

Section 4.05A Preferential Rights to Purchase and Consents. Seller shall use its reasonable efforts, but without any obligation to incur any cost or expense in connection therewith (other than de minimis amounts), to comply with all preferential right to purchase provisions relative to any Asset prior to the Closing. Prior to the Closing, Seller shall notify Buyer of the existence of any preferential purchase rights, if any preferential purchase rights are exercised or if the requisite period has elapsed without said rights having been exercised. If a third party who has been offered an interest in any Asset pursuant to a preferential right to purchase elects prior to the Closing to purchase all or part of such Asset pursuant to the aforesaid offer, the interest or part thereof so affected will be eliminated from the Assets and the Purchase Price shall be reduced by the Allocated Value of such Asset. Otherwise, the interest offered as aforesaid shall be conveyed to Buyer at the Closing subject to any preferential right to purchase of any third party for which notice has been given but the time period for response by the holder of such preferential right extends beyond the Closing and Buyer shall assume all duties, obligations and liabilities arising from such preferential right to purchase. Without limiting the foregoing, if any such third party elects to purchase all or a part of an interest in any Asset subject to a preferential right to purchase after the Closing Date, Buyer shall be obligated to convey said interest to such third party and shall be entitled to the consideration for the sale of such interest or part thereof.

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Seller shall use all reasonable efforts to obtain all necessary consents from third parties to assign the Assets prior to Closing (other than governmental approvals that are customarily obtained after Closing) and Buyer shall assist Seller with such efforts.

Section 4.06 Environmental Matters.

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Section 4.07 Limitation of Remedies for Title and Environmental Defects. Notwithstanding anything to the contrary contained in Article IV hereof, (a) if the Defect Value of a given Title Defect or the Remediation Value Adjustment of a given Environmental Defect does not exceed $25,000, as determined pursuant to Article IV or Article XV hereof, then no adjustment to the Purchase Price shall be made for such Title Defect or Environmental Defect and no such Title Defect or Environmental Defect shall be counted toward the Aggregate Deductible, (b) if the aggregate net adjustment to the Purchase Price determined in accordance with this Agreement for all Title Defects and Environmental Defects does not exceed 2% of the Purchase Price (the “Aggregate Deductible”), then no adjustment to the Purchase Price shall be made therefor, and (c) if the aggregate net adjustment to the Purchase Price determined in accordance with this Agreement for all Title Defects and Environmental Defects does exceed the Aggregate Deductible, then the Purchase Price shall only be adjusted by the amount of such excess. If Seller elects to retain any Assets related to an Environment Defect under Section 4.06, the Environmental Defect Value with respect to all such Environmental Defects shall not be counted towards the Aggregate Deductible.

ARTICLE V

Representations and Warranties of Seller

Section 5.01 Representations and Warranties. Seller represents and warrants to Buyer that:

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(1) any damage, destruction, or loss to or of the Assets whether or not covered by insurance, that has had, or would reasonably be expected to have, a material adverse effect on the Assets taken as a whole;

(2) any sale or other disposition of the Assets other than sales of Hydrocarbons in the ordinary course of business and a supplement to the TCW Net Profits Interest;

(3) the creation of any encumbrances on the Assets, except for the Excluded Assets, the TCW Net Profits Interest and liens which are to be released at Closing pursuant to Section 10.07;

(4) execution, amendment, waiver, or termination of any provision of any material Contract, agreement or instrument related to the Assets, other than the TCW Net Profits Interest;

(5) any election not to participate in any operation proposed to be conducted with respect to the Assets under any joint operating agreement;

(6) the incurrence of any expenses or other obligations relating to the Assets other than in the ordinary course of business consistent with past practices; or

(7) failure to pay cash calls for operation in which Seller elected to participate with respect to the Assets.

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Section 5.02 Seller’s Representations and Warranties Exclusive. All representations and warranties of Seller contained in this Agreement (including those in Article V) and in the Assignment and the other documents delivered in connection herewith, are exclusive, and are given in lieu of all other representations and warranties, express, implied or statutory.

ARTICLE VI

Representations and Warranties of Buyer

Section 6.01 Representations and Warranties. Buyer represents and warrants to Seller that:

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Section 6.02 Buyer’s Representations and Warranties Exclusive. All representations and warranties of Buyer contained in this Agreement (including those in Article VI), and the documents delivered in connection herewith, are exclusive, and are given in lieu of all other representations and warranties, express, implied or statutory.

ARTICLE VII

Operation of the Assets After the Closing

Seller does not warrant or guarantee that Buyer or WEG will become the operator of the Assets or any portion thereof, as such matter will be controlled by the applicable joint operating agreement(s) and governmental regulations.

ARTICLE VIII

Conditions to Obligations of Seller

Except as may be waived in writing by Seller, all of the obligations of Seller to consummate the transactions provided for herein are subject to and conditioned upon, at the option of Seller, the fulfillment by Buyer, on or prior to the Closing Date, of each of the following conditions:

Section 8.01 Representations. The representations and warranties of Buyer in this Agreement shall be true and correct in all material respects at and as of the Closing Date as though made on and as of such date, except that those representations and warranties which address matters only as of a particular date shall remain true and correct as of such date.

Section 8.02 Performance. Buyer shall have performed or complied with all of its material obligations, covenants and agreements contained in this Agreement to be performed or complied with by it at or prior to the Closing Date.

Section 8.03 Pending Matters. No suit, action, bankruptcy or other proceeding by or before any court or Governmental Authority shall be pending or threatened that seeks to, or could reasonably result in a judicial order, judgment or decree that would, restrain, prohibit, invalidate, or collect damages arising out of the transactions contemplated by this Agreement or which, in the reasonable judgment of Seller, makes it inadvisable to proceed with the transactions contemplated hereby.

Section 8.04 Bonds. Buyer shall have acquired and posted at or before Closing, any and all bonds required by any and all other applicable Governmental Authority to own and operate the Assets.

Section 8.05 Closing Deliveries. Seller shall have received the Purchase Price referred to in Section 2.01, above, subject to the adjustments thereto provided for in Section 10.03, below

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in this Agreement, in the amount set forth in the Pre-Closing Statement determined pursuant to Section 10.04 of this Agreement, and all other documents and certificates, duly executed in a form reasonably acceptable to Seller, required to be delivered by Buyer in Section 10.08 below.

ARTICLE IX

Conditions to Obligations of Buyer

Except as may be waived by Buyer, all of the obligations of Buyer to consummate the transactions provided for herein are subject to and conditioned upon, at the option of Buyer, to the fulfillment by Seller, on or prior to the Closing Date, of each of the following conditions:

Section 9.01 Representations. The representations and warranties of Seller in this Agreement shall be true and correct in all material respects at and as of the Closing Date as though made on and as of such date, except that those representations and warranties which address matters only as of a particular date shall remain true and correct as of such date.

Section 9.02 Performance. Seller shall have performed or complied with all of its material obligations, covenants and agreements contained in this Agreement to be performed or complied with by it at or prior to the Closing Date.

Section 9.03 Pending Matters. No suit, action, bankruptcy or other proceeding by or before any court or Governmental Authority, shall be pending or threatened that seeks to, or could reasonably result in a judicial order, judgment or decree that would, restrain, prohibit, invalidate, enjoin, or collect damages arriving out of the transactions contemplated by this Agreement, or which in the reasonable judgment of Buyer, makes it inadvisable to proceed with the transactions contemplated by this Agreement.

Section 9.04 Closing Deliveries. Buyer shall have received all documents and certificates, duly executed, in form acceptable to Buyer, which are required to be delivered at Closing by Seller pursuant to Section 10.07, below.

ARTICLE X

The Closing

Section 10.01 Time and Place of the Closing. If the conditions referred to in Articles VIII and IX of this Agreement have been satisfied or waived in writing, the transactions contemplated by this Agreement (the “Closing”) shall take place at the offices of ExL in Midland, Texas on December 19, 2007, or as such date may be extended pursuant to Section 10.02 (the “Closing Date”).

Section 10.02 Extension. The Closing Date may be extended by mutual written agreement of the Parties.

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Section 10.03 Adjustments to Purchase Price. The Purchase Price shall be adjusted on the Closing Date in the following manner, pursuant to the procedure for doing so set forth in Section 10.04, below:

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Section 10.04 Pre-Closing Allocations/Statement.

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Section 10.05 Post-Closing Adjustments to Purchase Price.

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Section 10.06 Ad Valorem and Other Taxes. All unpaid ad valorem, property and similar taxes and assessments based upon or measured by the value of the Subject Interests and attributable to the period prior to the Effective Time will be paid by the Seller and all unpaid ad valorem, property and similar taxes and assessments based upon or measured by the value of the Subject Interests and attributable to the period after the Effective Time will be paid by the Buyer. All sales, use or other similar taxes (other than taxes on gross income, net income or gross receipts) and duties, levies, recording fees or other governmental charges incurred by or imposed with respect to the property transfers undertaken pursuant to this Agreement shall be the responsibility of, and shall be paid by, Buyer.

Section 10.07 Actions of Seller at the Closing. At the Closing, Seller shall execute (where applicable) and deliver to Buyer the following, all of which shall in form and content reasonably satisfactory to Buyer:

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Section 10.08 Actions of Buyer at the Closing. At the Closing, Buyer shall execute (where applicable) and deliver to Exl Petroleum, LP, for the benefit of the Parties Seller, the following, all of which shall be in form and content reasonably satisfactory to Seller:

Section 10.09 Recordation; Further Assurances.

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ARTICLE XI

Risk of Loss

Title, possession and risk of loss with respect to the Assets shall pass from Seller to Buyer at 10:00 o’clock a.m. (CST) on the Closing Date, but effective as of the Effective Time, provided Buyer and Seller have performed their respective obligations under this Agreement and all conditions to the Closing have been fully satisfied or waived by the applicable Party.

ARTICLE XII

Covenants of Seller

Section 12.01 Consummation of Agreement. Seller shall use reasonable good faith efforts to cause the consummation by Seller of the transactions contemplated by this Agreement in accordance with the terms and conditions of this Agreement.

Section 12.02 Access. Prior to the Closing Date, Seller shall permit Buyer and its authorized representatives full access to, and make available for, inspection, all of the Assets which are being conveyed pursuant to this Agreement, including, specifically, all of the Records, whether electronic or paper, maintained by Seller on the Wells, Leases and Subject Interests, and will permit Buyer and its authorized representatives to inspect and make copies, at Buyer’s expense, of all documents, records, and information with respect to the Assets as Buyer and its representatives may reasonably request, all for the sole purpose of permitting Buyer to become familiar with the Assets provided that, all such access and information shall be during normal business hours.

Section 12.03 Notice of Material Change. Seller shall give prompt notice in writing to Buyer of the occurrence or non-occurrence of any event which would likely cause any representation or warranty made by Seller herein to be untrue or inaccurate in any material respect, or any covenant, condition or agreement contained herein not to be complied with or satisfied in any material respect (provided however, that any such disclosure shall not in any way be deemed to amend, modify or in any way affect the representations, warranties and covenants made by any Party in or pursuant to this Agreement).

Section 12.04 No Negotiation with Others. Seller shall not solicit or participate in negotiations with (and will prevent any affiliate, shareholder, member, director, officer, manager, employee or other representative or agent of Seller from negotiating with, soliciting or participating in negotiations with) any third party with respect to the sale of the Assets until close of business on the Closing Date. Seller shall notify Buyer promptly upon becoming aware of any activity proscribed by this Section 12.04.

Section 12.05 Cooperation. Seller shall cooperate with Buyer, without being obligated to incur any unreimbursable expense (a) in the notification of all applicable governmental regulatory agencies, oil and gas purchasers and third party operators of the transactions contemplated hereby and shall cooperate with Buyer in obtaining the issuance by each such

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authority of such permits, licenses, and authorizations as may be necessary for Buyer to own and operate the Wells and Leases following the consummation of the transactions contemplated by this Agreement, (b) to execute, acknowledge and deliver to Buyer such further documentation as needed after Closing as may be reasonably requested in order to more effectively assure that all the respective rights, titles and privileges intended to be assigned, delivered or inuring to the benefit of Buyer in consummation of the transactions contemplated herein are properly conveyed to Buyer, and (c) in obtaining financial information related to the Assets necessary for Buyer to produce auditable historical financial statements on the Assets.

Section 12.06 Operation of the Assets.

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ARTICLE XIII

Covenants of Buyer

13.01 Consummation. Buyer shall use its reasonable good faith efforts to cause the consummation by Buyer of the transactions contemplated by this Agreement in accordance with the terms and conditions of the Agreement.

13.02 Notice of Material Change. Buyer shall give prompt notice in writing to Seller of the occurrence or non-occurrence of any event which would likely cause any representation or warranty made by Buyer herein to be untrue or inaccurate or any covenant, condition or agreement contained herein, not to be complied with or satisfied (provided however, that any such disclosure shall not in any way be deemed to amend, modify or in any affect the representations, warranties and covenants made by any part in or pursuant to this Agreement).

13.03 Confidentiality. Seller has previously provided to Buyer and will continue to provide to Buyer certain information, in oral, written and/or electronic format, pertaining to and for Buyer’s sole purpose of evaluating the Assets for purchase by Buyer (the “Confidential Information”). Buyer acknowledges and agrees that the Confidential Information constitutes valuable assets of Seller and that Seller desires and requires that the Confidential Information remain confidential and proprietary.

The Confidential Information will be kept confidential and shall not, unless in the opinion of counsel for Buyer disclosure is required by law or with the prior written consent of Seller, be disclosed by the Buyer or any of its directors, officers, employees, agents, representatives,

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affiliates, subsidiaries, related companies, or any other party related to or controlled by Buyer, in any manner whatsoever, in whole or in part, to third parties not described below and shall not be used by Buyer, or any of its directors, officers, employees, agents, representatives, affiliates, subsidiaries, related companies, or any other party related to or controlled by Buyer, other than in connection with the transaction described in this Agreement. Moreover, Buyer agrees that the Confidential Information will be revealed only to its lenders, officers, directors, employees, agents, representatives, affiliates, subsidiaries and related companies who need to know the Confidential Information for the purpose of evaluating the transaction described in this Agreement, all of whom will be informed by Buyer of the confidential nature of the Confidential Information and all of whom will be required by Buyer to refrain from using any Confidential Information for their own use.

The terms of this Agreement shall not apply to any Confidential Information which (a) is or becomes generally available to the public, other than as a result of a disclosure by Buyer, or (b) is or becomes available to Buyer on a nonconfidential basis from a source which is not known to Buyer to be prohibited from disclosing such information to Buyer by a legal, contractual or fiduciary obligation to Seller.

All Confidential Information which comes into Buyer’s possession and control or acknowledged to be the property of Seller will be promptly surrendered to Seller upon the termination of this Agreement pursuant to Section 16.01. Additionally, Buyer will likewise promptly destroy all electronic Confidential Information and all copies, summaries and notes regarding any Confidential Information which are made by Buyer in connection with this Agreement and will subsequently represent to Seller that such has been destroyed. After the termination of this Agreement, Buyer shall make no further use of any Confidential Information. This will apply regardless of the reasons for or circumstances surrounding such expiration or termination.

The provisions of this Section 13.03 shall terminate and be of no further force and effect upon Closing.

ARTICLE XIV

Good Will

The Parties agree that the portion of the Purchase Price to be allocated to good will for purposes of this transaction is One Hundred and No One Hundredths Dollars ($100.00), and no further amount will be allocated or claimed with respect thereto by any Party hereto. The Parties acknowledge and agree to the tax consequences of this allocation and agree to report the tax consequences arising therefrom in accordance with the allocation of only One Hundred and No One Hundredths Dollars ($100.00) to this Section and the restrictions contained herein.

ARTICLE XV

Arbitration

If any matter is required to be arbitrated pursuant to the terms and conditions of this Agreement, such arbitration shall be conducted in the manner set forth in this Article:

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Section 15.01 Selection of Arbitrator. The Parties shall jointly select a mutually acceptable person as the sole arbitrator under this Agreement (“Arbitrator”). The Arbitrator shall be selected by the Parties, (acting reasonably and in good faith) within ten (10) days following the receipt of the notice of any demand made for arbitration pursuant to the terms of this Agreement by any Party hereto, and shall be a person who is independent, impartial, and knowledgeable in the subject matter and substantive laws as to the subject of the arbitration. Each Party shall bear its own costs and expenses incurred in connection with any such proceeding, and one-half (1/2) of the costs and expenses of the Arbitrator. If the Parties are unable to select a Arbitrator pursuant to the foregoing procedure, then they shall submit the matter to the American Arbitration Association (“AAA”) and ask that the AAA designate an Arbitrator who satisfies the foregoing qualifications within ten (10) days after such request is made by them to AAA.

Section 15.02 Place of Hearing. Any arbitration hearing shall be held at a place in Dallas, Texas, acceptable to the Arbitrator.

Section 15.03 Rules of Arbitration. The Arbitrator shall settle any disputes in accordance with procedures and rules mutually agreed upon by the Parties and failing such agreement, in accordance with the rules or procedures for non-administered arbitration set forth in the Commercial Arbitration Rules of the AAA in effect at the time of the arbitration. The Arbitrator shall resolve the dispute in accordance with the governing law selected by the Parties in Section 19.10 below, and shall be instructed by the Parties to resolve such dispute as soon as reasonably practicable, in light of the circumstances, utilizing the terms and provisions of this Agreement with respect to Title and Environmental Matters as guidance and direction for such decisions, and to conduct such arbitration in the time and manner provided for in Section 15.04, below. The decision and award of the Arbitrator shall be binding upon the Parties and final and nonappealable to the maximum extent permitted by applicable law, and judgment thereon may be entered in a court of competent jurisdiction and enforced by any Party as a final judgment of such court. Seller and Buyer, respectively, shall bear their own legal fees and other costs incurred in presenting their respective cases to the Arbitrator.

Section 15.04 Time of the Arbitration Procedure. The arbitration shall commence within ten (10) days after the Arbitrator is selected as set forth in Section 15.01, above, unless the Parties and the Arbitrator shall agree to some other commencement date. The hearing shall not last more than two (2) days with each Party being allowed the maximum of one (1) day for presentation of their evidence. In fulfilling its duties hereunder, the Arbitrator shall be bound by the terms of this Agreement. In fulfilling any of its arbitration duties, the Arbitrator may also consider such other matters which, in the opinion of the Arbitrator, are necessary or helpful to make a proper evaluation of the matter disputed. Additionally, the Arbitrator may consult with and engage, as a part of the Arbitrator’s expenses, disinterested third parties, including, without limitation, petroleum engineers, geologists, attorneys, and consultants to advise the Arbitrator or to the resolution of the subject matter of the arbitration. If any Arbitrator selected hereunder should die, resign or be unable to perform his duties hereunder, a replacement Arbitrator shall be mutually selected by the Parties or, absent mutual agreement, by the AAA in the foregoing manner. The aforesaid procedure shall be followed from time to time as necessary.

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Section 15.05 Decision. The Arbitrator shall be instructed to use his reasonable best efforts to deliver his final decision within ten (10) days of the conclusion of the arbitration hearing.

ARTICLE XVI

Termination

Section 16.01 Right of Termination. This Agreement may be terminated at any time at or prior to the Closing:

Section 16.02 Effect of Termination. In the event of the termination of this Agreement by Seller pursuant to Section 16.01(c) hereof due to Buyer’s failure to meet a condition of Closing, Seller may terminate this Agreement and retain the Earnest Money Deposit and any accrued interest thereon as its sole remedy. In the event Buyer terminates this Agreement pursuant to Section 16.01(d) hereof due to Seller’s failure to meet a condition of Closing, Buyer may pursue its rights and remedies against Seller for Seller’s breach of this Agreement and receive back the Earnest Money Deposit, with accrued interest. In the event of the termination of this Agreement pursuant to either Section 16.01 (a), (b), (e) or (f) hereof, the termination shall be without penalty and the Parties shall have no further obligations to, nor rights against, one another, except that Seller shall return the Earnest Money Deposit to Buyer, with accrued interest. Notwithstanding the preceding sentence, in the event of the termination of this

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Agreement for any reason, such termination shall not relieve Buyer of its indemnity obligations under Section 4.06, its confidentiality obligations under Section 13.03 or its obligations under Section 16.03.

Section 16.03 Return of Documentation. Upon termination of this Agreement, Buyer shall promptly return to Seller all title, geological data, reports, contracts, and maps and other information furnished by Seller to Buyer and destroy or return all copies thereof.

ARTICLE XVII

Assumption and Indemnification

Section 17.01 Seller’s Retained Obligations. Provided that the Closing occurs, Seller shall retain the following: (a) all Claims and Liabilities of Seller for the payment or improper payment of royalties, rentals and other similar payments by Seller under the Leases relating to the Subject Interests accruing during the period prior to the Effective Time (to the extent Buyer has provided Seller with written notice claiming indemnification therefor within one (1) year of the Closing pursuant to Section 17.07, and not thereafter); (b) all Liability of Seller to third parties for personal injury or death to the extent occurring prior to the Effective Time as a result of the operation of the Assets by Seller or its affiliates; (c) ad valorem, property, severance and similar taxes attributable to the period of time prior to the Effective Time retained by Seller under Section 10.06; and (d) Liability for any contamination or condition that is the result of any off-site disposal by Seller or its affiliates of any wastes, pollutants, contaminants, hazardous material or other material or substances on, in or below any properties not included in the Assets prior to the Effective Time, for which, and to the extent, that remediation of such contamination or condition is required by any Environmental Law (collectively, the “Retained Obligations”).

Section 17.02 Buyer’s Assumed Obligations. Provided that the Closing occurs, Buyer hereby assumes all duties, obligations, Claims and Liabilities of every kind and character with respect to the Assets or the ownership or operation thereof (other than the Retained Obligations), whether attributable to periods before or after the Effective Time, including, without limitation, those arising out of (a) the terms of the Surface Agreements, Contracts, Leases or Subject Interests comprising part of the Assets, (b) Gas Imbalances, (c) suspense accounts, (d) ad valorem, property, severance and other similar taxes or assessments based upon or measured by the ownership of the Assets or the production therefrom, (e) the condition of the Assets, regardless of whether such condition arose before or after the Effective Time, (f) obligations to properly plug and abandon or re-plug or re-abandon or remove wells, flowlines, gathering lines and other facilities, equipment or other personal property or fixtures comprising part of the Assets, (g) obligations to restore the surface of the Assets and obligations to bring the Assets into compliance with applicable Environmental Laws (including conducting any remediation activities that may be required on or otherwise in connection with activities on the Assets), regardless of whether such obligations or conditions or events giving rise to such obligations, arose, occurred or accrued before or after the Effective Time, (h) any other duty, obligation, event, condition or liability assumed by Buyer under the terms of this Agreement, (i) alleged Title Defects and Environmental Defects that are deemed to constitute Assumed Obligations under Article IV, and (j) the obligations and liabilities described in Section 17.01(a) to the extent Buyer does not provide Seller with written notice claiming indemnification therefor within one (1) year of the Closing (collectively, the “Assumed Obligations”).

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Section 17.03 Definition of Claims and Liabilities. The term “Claims” means any and all direct or indirect, demands, claims, notices of violation, notices of probable violation, filings, investigations, administrative proceedings, actions, causes of action, suits, other legal proceedings, judgments, assessments, damages, deficiencies, taxes, penalties, fines, obligations, responsibilities, liabilities, payments, charges, costs, and expenses (including costs and expenses of operating the Assets) of any kind or character (whether or not asserted prior to Closing, and whether known or unknown, fixed or unfixed, conditional or unconditional, based on negligence, strict liability or otherwise, choate or inchoate, liquidated or unliquidated, secured or unsecured, accrued, absolute, contingent, or other legal theory), including penalties and interest on any amount payable as a result of any of the foregoing, any legal or other costs and expenses incurred in connection with investigating or defending any Claim, and all amounts paid in settlement of Claims. Without limiting the generality of the foregoing, the term “Claims” specifically includes any and all Claims arising from, attributable to or incurred in connection with any (a) breach of contract, (b) loss or damage to property, injury to or death of persons, and other tortuous injury and (c) violations of applicable laws, rules, regulations, orders, including Environmental Laws, or any other legal right or duty actionable at law or equity. The term, “Liability or Liabilities” shall mean collectively, all damages, (including consequential and punitive damages), including those for personal injury, death, or damage or destruction to personal or real property (both surface and subsurface), costs for remediation, restoration, or clean up of contamination, whether the injury, death, or damage occurred or occurs on or off any of the Subject Interests by migration, disposal, or otherwise; losses; fines; penalties, expenses; costs to remove or modify Facilities on or under the Subject Interests; plugging liabilities for all Wells; attorneys’ fees; court and other costs incurred in defending a Claim; liens; and judgments; in each instance, whether these damages and other costs are foreseeable or unforeseeable.

Section 17.04 Application of Indemnities. All indemnities set forth in this Agreement extend to the affiliates, partners, directors, employees, agents, representatives, members, shareholders, subsidiaries, heirs, successors and assigns of the indemnified party. The indemnities set forth in this Agreement do not extend to any part of an indemnified Claim that is the result of the gross negligence, willful misconduct or fraud of the indemnified party.

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Section 17.05 Buyer’s Indemnity. PROVIDED THAT THE CLOSING OCCURS, BUYER SHALL INDEMNIFY, DEFEND AND HOLD SELLER HARMLESS FROM AND AGAINST ANY AND ALL CLAIMS AND LIABILITIES CAUSED BY, RESULTING FROM OR INCIDENTAL TO THE ASSUMED OBLIGATIONS, AND ANY CLAIMS AND LIABILITIES CAUSED BY, RESULTING FROM OR ATTRIBUTABLE TO (A) ANY INACCURACY OF ANY REPRESENTATION OR WARRANTY OF BUYER SET FORTH IN THIS AGREEMENT, (B) ANY BREACH OF, OR FAILURE TO PERFORM OR SATISFY, ANY OF THE COVENANTS AND OBLIGATIONS OF BUYER HEREUNDER, AND (C) ANY MATTER ARISING OR RESULTING FROM BUYER’S OWNERSHIP AND OPERATION OF THE ASSETS AFTER THE EFFECTIVE TIME.

Subject 17.06 Seller’s Indemnity. SUBJECT TO SECTION 17.08, SELLER SHALL INDEMNIFY, DEFEND AND HOLD BUYER HARMLESS FROM AND AGAINST ANY AND ALL CLAIMS AND LIABILITIES CAUSED BY, RESULTING FROM OR INCIDENTAL TO THE RETAINED OBLIGATIONS, AND ANY CLAIMS AND LIABILITIES CAUSED BY OR RESULTING FROM (A) ANY INACCURACY OF ANY REPRESENTATION OR WARRANTY OF SELLER SET FORTH IN THIS AGREEMENT THAT SURVIVES THE CLOSING, EXCEPT FOR THOSE WHICH ARE WAIVED BY OR DEEMED WAIVED BY BUYER PURSUANT TO THE TERMS IF THIS AGREEMENT OR WHICH CONSTITUTE PERMITTED ENCUMBRANCES AND/OR ASSUMED OBLIGATIONS, (B) ANY BREACH OF, OR FAILURE TO PERFORM OR SATISFY, ANY OF THE COVENANTS AND OBLIGATIONS OF SELLER HEREUNDER WHICH ARE TO BE PERFORMED AFTER THE CLOSING.

Section 17.07 Notices and Defense of Indemnified Claims. Each Party shall immediately notify the other Party of any Claim of which it becomes aware and for which it is

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entitled to indemnification from the other Party under this Agreement. The indemnifying Party shall be obligated to defend, at the indemnifying Party’s sole expense, any litigation or other administrative or adversarial proceeding against the indemnified Party relating to any Claim for which the indemnifying Party has agreed to indemnify and hold the indemnified Party harmless under this Agreement. However, the indemnified Party shall have the right to participate with the indemnifying Party in the defense of any such Claim and may retain its own separate counsel to do so at its own sole cost and expense.

Section 17.08 Indemnity Limits. Notwithstanding anything to the contrary contained herein, (a) Seller’s indemnification obligation under Section 17.06 shall only apply if Buyer has provided Seller with written notice claiming indemnification within six (6) months after the Closing, and (b) Buyer shall bear sole responsibility for the aggregate costs associated with all Claims and Liabilities for which Seller has indemnified Buyer up to a deductible percentage of two percent (2%) of the Purchase Price. By the prior sentence, it is the intent that Seller shall only be obligated to provide indemnity to the extent such Claims and Liabilities exceed the deductible percentage of two percent (2%) of the Purchase Price. In no event shall Seller be required to indemnify Buyer for any amount or to pay any other amount in connection with or with respect to the transactions contemplated in this Agreement exceeding in the aggregate twenty percent (20%) of the Purchase Price.

Section 17.09 Survival. The representations and warranties of Seller set forth in Sections 5.01(a) through 5.01(f) shall survive the Closing indefinitely. The representations of Seller set forth in Sections 5.01(g) through 5.01(s) shall survive the Closing for a period of one (1) year after Closing. All other representations, warranties, covenants and agreements contained in this Agreement shall survive the Closing indefinitely; provided however that (i) any covenants and agreements of Seller or Buyer that are to be performed prior to or at the Closing shall terminate upon the Closing, and (ii) nothing herein shall extend the one (1) year period after Closing in which Buyer may send written notice claiming indemnification under Section 17.07 and Buyer thereafter expressly waives all other rights to make any claim against Seller in accordance with Section 17.07. The obligations and covenants of Buyer under this Agreement that survive the Closing shall be deemed covenants running with the land.

Section 17.10 Exclusive Remedy. The terms and provisions of this Article XVII, and Article IV, as applicable, and Article VII shall be the sole and exclusive remedy of each of the Parties indemnified hereunder with respect to the representations, warranties, covenants and agreements of the Parties set forth in this Agreement and the other documents executed and delivered hereunder.

Section 17.11 Defenses and Counterclaims. Each Party that is required to assume any obligation or liability of the other Party pursuant to this Agreement or that is required to defend, indemnify or hold the other Party harmless hereunder shall, notwithstanding any other provision hereof to the contrary, be entitled to the use and benefit of all defenses (legal and equitable) and counterclaims of such other Party in defense of third party Claims arising out of any such assumption or indemnification.

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ARTICLE XVIII

Disclaimers; Casualty Loss and Condemnation

Section 18.01 Disclaimers of Representations and Warranties. The express representations and warranties of Seller contained in this Agreement are exclusive and are in lieu of all other representations and warranties, express, implied or statutory. BUYER ACKNOWLEDGES THAT SELLER HAS NOT MADE, AND SELLER HEREBY EXPRESSLY DISCLAIMS AND NEGATES, AND BUYER HEREBY EXPRESSLY WAIVES, ANY REPRESENTATION OR WARRANTY, EXPRESS, IMPLIED, AT COMMON LAW, BY STATUTE OR OTHERWISE, RELATING TO (a) PRODUCTION RATES, RECOMPLETION OPPORTUNITIES, DECLINE RATES, GAS BALANCING INFORMATION OR THE QUALITY, QUANTITY OR VOLUME OF THE RESERVES OF HYDROCARBONS, IF ANY, ATTRIBUTABLE TO THE ASSETS AND (b) THE ACCURACY, COMPLETENESS OR MATERIALITY OF ANY INFORMATION, DATA OR OTHER MATERIALS (WRITTEN OR ORAL) NOW, HERETOFORE OR HEREAFTER FURNISHED TO BUYER BY OR ON BEHALF OF SELLER. NOTWITHSTANDING ANYTHING TO THE CONTRARY IN THIS AGREEMENT, SELLER EXPRESSLY DISCLAIMS AND NEGATES, AND BUYER HEREBY WAIVES, AS TO PERSONAL PROPERTY, EQUIPMENT, INVENTORY, MACHINERY AND FIXTURES CONSTITUTING A PART OF THE ASSETS (i) ANY IMPLIED OR EXPRESS WARRANTY OF MERCHANTABILITY, (ii) ANY IMPLIED OR EXPRESS WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE, (iii) ANY IMPLIED OR EXPRESS WARRANTY OF CONFORMITY TO MODELS OR SAMPLES OF MATERIALS, (iv) ANY RIGHTS OF PURCHASERS UNDER APPROPRIATE STATUTES TO CLAIM DIMINUTION OF CONSIDERATION OR RETURN OF THE PURCHASE PRICE, (v) ANY IMPLIED OR EXPRESS WARRANTY OF FREEDOM FROM DEFECTS, WHETHER KNOWN OR UNKNOWN, AND (vi) ANY AND ALL IMPLIED WARRANTIES EXISTING UNDER APPLICABLE LAWS, RULES, STATUTES, REGULATIONS, ORDERS OR DECREES, IT BEING THE EXPRESS INTENTION OF BUYER AND SELLER THAT THE ASSETS, INCLUDING ALL PERSONAL PROPERTY, EQUIPMENT, INVENTORY, MACHINERY AND FIXTURES INCLUDED IN THE ASSETS, SHALL BE CONVEYED TO BUYER, AND BUYER SHALL ACCEPT SAME, AS IS, WHERE IS, WITH ALL FAULTS AND IN THEIR PRESENT CONDITION AND STATE OF REPAIR, AND BUYER REPRESENTS TO SELLER THAT BUYER HAS MADE OR CAUSED TO BE MADE SUCH INSPECTIONS WITH RESPECT TO SUCH ASSETS AS BUYER DEEMS APPROPRIATE. SELLER AND BUYER AGREE THAT, TO THE EXTENT REQUIRED BY APPLICABLE LAW TO BE EFFECTIVE, THE DISCLAIMERS OF CERTAIN WARRANTIES CONTAINED IN THIS SECTION ARE “CONSPICUOUS” DISCLAIMERS FOR THE PURPOSES OF ANY APPLICABLE LAWS, RULES, STATUTES, REGULATIONS, ORDERS OR DECREES RULE OR ORDER.

Section 18.02 NORM. BUYER ACKNOWLEDGES THAT IT HAS BEEN INFORMED THAT OIL AND GAS PRODUCING FORMATIONS CAN CONTAIN NATURALLY OCCURRING RADIOACTIVE MATERIAL (“NORM”). SCALE FORMATION OR SLUDGE DEPOSITS CAN CONCENTRATE LOW LEVELS OF NORM ON EQUIPMENT AND OTHER ASSETS. THE ASSETS SUBJECT TO THIS

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AGREEMENT MAY HAVE LEVELS OF NORM ABOVE BACKGROUND LEVELS, AND A HEALTH HAZARD MAY EXIST IN CONNECTION WITH THE ASSETS BY REASON THEREOF. THEREFORE, BUYER MAY NEED TO FOLLOW SAFETY PROCEDURES WHEN HANDLING THE EQUIPMENT AND OTHER ASSETS.

Section 18.03 Casualty Loss; Condemnation.

Section 18.04 Deceptive Trade Practice Act. BUYER EXPRESSLY WAIVES THE PROVISIONS OF CHAPTER XVII, SUBCHAPTER E, SECTIONS 17.41 THROUGH 17.63, INCLUSIVE (OTHER THAN SECTION 17.555, WHICH IS NOT WAIVED), VERNON’S TEXAS CODE ANNOTATED BUSINESS AND COMMERCE CODE (THE “DECEPTIVE TRADE PRACTICES ACT”).

ARTICLE XIX

Miscellaneous

Section 19.01 Names. As soon as reasonably possible after the Closing, but in no event later than forty five (45) days after the Closing, Buyer shall remove the names of Seller and its affiliates, and all variations thereof, from all of the Assets and make the requisite filings with, and provide the requisite notices to, the appropriate Governmental Authorities to place the title or other indicia or responsibility of ownership in a name other than the name of the Seller or any of its affiliates, or any variations thereof.

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Section 19.02 Expenses. Each Party shall be solely responsible for all expenses, including due diligence expenses, attorney, and accounting fees, incurred by it in connection with this transaction, and neither Party shall be entitled to any reimbursement for any such expenses from the other Party, unless the other Party materially breaches the terms and conditions of this Agreement.

Section 19.03 Document Retention. As used in this Section 19.03, the term “Documents” shall mean all files, documents, books, records and other data delivered to Buyer by Seller pursuant to the provisions of this Agreement (other than those that Seller has retained either the original or a copy of), including financial and tax accounting records; land, title and division order files; contracts; engineering and well files; and books and records related to the operation of the Assets prior to the Closing Date. Buyer shall retain and preserve the Documents for a period of no less than five (5) years following the Closing Date (or for such longer period as may be required by law or governmental regulation), and shall allow Seller or its representatives to inspect the Documents at reasonable times and upon reasonable notice during regular business hours during such time period. Seller shall have the right during such period to make copies of any of the Documents at its expense.

Section 19.04 Entire Agreement. This Agreement, the documents to be executed and delivered hereunder, and the Exhibits, Schedules and Appendices attached hereto constitute the entire agreement between the Parties pertaining to the subject matter hereof and supersede all prior agreements, understandings, negotiations and discussions, whether oral or written, of the Parties pertaining to the subject matter hereof. No supplement, amendment, alteration, modification or waiver of this Agreement shall be binding unless executed in writing by each of the Parties and specifically referencing this Agreement.

Section 19.05 Waiver. Any waiver must be in writing executed by the waiving Party and no waiver of any provision of this Agreement shall be deemed or shall constitute a waiver of any other provision hereof (whether or not similar), nor shall such waiver constitute a continuing waiver unless otherwise expressly provided.

Section 19.06 Publicity. Seller and Buyer shall consult with each other with regard to all publicity and other releases concerning this Agreement and the transactions contemplated hereby and, except as required by applicable law or the applicable rules or regulations of any Governmental Authority or stock exchange, neither Party shall issue any such publicity or other release without the prior written consent of the other Party hereto, such consent not to be unreasonably withheld.

Section 19.07 Construction. The captions in this Agreement are for convenience only and shall not be considered a part of or affect the construction or interpretation of any provision of this Agreement.

Section 19.08 No Third Party Beneficiaries. Except as provided in Sections 17.08 and 17.09, nothing in this Agreement shall provide any benefit to any third party or entitle any third party to any claim, cause of action, remedy or right of any kind, it being the intent of the Parties that this Agreement shall otherwise not be construed as a third party beneficiary contract.

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Section 19.09 Assignment. Except as provided in Section 2.04, neither Party may assign or delegate any of its rights or duties under this Agreement without the prior written consent of the other Party; provided, however, Buyer may without the consent of Seller assign all or a portion of its rights under this Agreement (a) to Gulfport Energy Corporation, or (b) to any affiliated entity (provided that an assignment to an affiliate of Buyer shall not relieve Buyer of its obligations hereunder). This Agreement shall be binding upon and inure to the benefit of the Parties hereto and their respective permitted successors, assigns and legal representatives.

Section 19.10 Governing Law; Venue; Jury Waiver. THIS AGREEMENT, THE OTHER DOCUMENTS DELIVERED PURSUANT HERETO, AND THE LEGAL RELATIONS BETWEEN THE PARTIES SHALL BE GOVERNED AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF TEXAS, EXCLUDING ANY CONFLICTS OF LAW, RULE OR PRINCIPLE THAT MIGHT REFER CONSTRUCTION OF THIS AGREEMENT AND SUCH OTHER DOCUMENTS TO THE LAWS OF ANOTHER JURISDICTION. ALL OF THE PARTIES HERETO CONSENT TO THE EXERCISE OF JURISDICTION IN PERSONAM BY THE COURTS OF THE STATE OF TEXAS FOR ANY ACTION ARISING OUT OF THIS AGREEMENT OR THE OTHER DOCUMENTS EXECUTED PURSUANT TO OR IN CONNECTION WITH THIS AGREEMENT. ALL ACTIONS OR PROCEEDINGS WITH RESPECT TO, ARISING DIRECTLY OR INDIRECTLY IN CONNECTION WITH, OUT OF, RELATED TO, OR FROM THIS AGREEMENT OR THE OTHER DOCUMENTS EXECUTED PURSUANT TO OR IN CONNECTION WITH THIS AGREEMENT SHALL BE EXCLUSIVELY LITIGATED IN COURTS HAVING SITES IN DALLAS, DALLAS COUNTY, TEXAS. EACH PARTY HERETO WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY ACTION, SUIT OR PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT.

Section 19.11 Notices. Any notice, communication, request, instruction or other document required or permitted hereunder (including notices of Title Defects or Environmental Defects) shall be given in writing and delivered in person or sent by U.S. Mail postage prepaid, return receipt requested, or by reliable overnight courier service, or facsimile transmission to the addresses of Seller and Buyer set forth below. Any such notice shall be effective and deemed given only upon receipt.

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Either Party may, by written notice so delivered to the other Party, change its address for notice purposes hereunder.

Section 19.12 Severability. If any term or other provision of this Agreement is invalid, illegal or incapable of being enforced by any rule of law or public policy, all other conditions and provisions of this Agreement shall nevertheless remain in full force and effect and the Parties shall negotiate in good faith to modify this Agreement so as to effect their original intent as closely as possible in an acceptable manner to the end that the transactions contemplated hereby are fulfilled to the extent possible.

Section 19.13 Interpretation. This Agreement shall be deemed and considered for all purposes to have been jointly prepared by the Parties, and shall not be construed against any one Party (nor shall any inference or presumption be made) on the basis of who drafted this Agreement or any particular provision hereof, who supplied the form of Agreement, or any other event of the negotiation, drafting or execution of this Agreement. Each Party agrees that this Agreement has been purposefully drawn and correctly reflects its understanding of the transaction that it contemplates. In construing this Agreement, the following principles will apply.

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Section 19.14 Time of the Essence. Time shall be of the essence with respect to all time periods and notice periods set forth in this Agreement.

Section 19.15 Facsimile; Counterpart Execution. This Agreement may be executed by facsimile and in any number of counterparts, and each counterpart hereof shall be effective as to each party that executes the same whether or not all of such parties execute the same counterpart. If counterparts of this Agreement are executed, the signature pages from various counterparts may be combined into one composite instrument for all purposes. All counterparts together shall constitute only one Agreement, but each counterpart shall be considered an original.

Section 19.16 Enforcement of the Agreement. The Parties agree that they will be irreparably damaged if any of the provisions of this Agreement are not fully performed by the other Party hereto, in accordance with their specific terms, or are otherwise breached. It is accordingly agreed that the Parties shall be entitled to obtain equitable relief in the form of an injunction or injunctions to prevent breach of this Agreement and to enforce specifically the terms and provisions hereof, this being in addition to, and cumulative of, any other remedy to which they may then be entitled to seek, whether at law or in equity.

Section 19.17 Prevailing Party. Should either the Buyer or the Seller employ an attorney or attorneys to enforce any of the terms and conditions hereof, or to protect any right, title or interest created or evidenced hereto, in any state or federal court, the non-prevailing party in any action pursued in courts of competent jurisdiction shall pay to the prevailing party all reasonable costs, damages and expenses, including reasonable attorneys’ fees, expended or incurred by the prevailing party.

Section 19.18 Several Not Joint; Obligations and Rights of Parties. The obligations of Parties Seller with respect to the Assets are several (and not joint and several) with respect to the working interests owned by each Party Seller in the Assets. Without limitation of the foregoing, any representation, warranty, indemnity or covenant made by Seller or the Parties Seller or any Party Seller herein or pursuant hereto, with respect to the Assets is only made by each Party Seller as to itself only or its interest in such Assets, as applicable.

Section 19.19 Seller’s Representative. All the Parties Seller hereby appoint ExL Petroleum LP to serve as their exclusive representative and agent (“Sellers’ Representative”) under this Agreement for the limited purpose of (i) exercising and performing, on their behalf, those rights and duties that are expressly designated herein as a right or duty of Seller, (ii) giving and receiving of notices and requests under this Agreement, (ii) making of adjustments to the

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Purchase Price, (iii) receiving of the Earnest Money Deposit, the Purchase Price and any other payments due the Parties Seller under this Agreement, and (iv) the allocating, and distributing of the Earnest Money Deposit, the Purchase Price and any other payments due the Parties Seller among the various Parties Seller. Buyer may act, and shall be fully protected in acting, in reliance upon any and all acts and things done and performed by or agreements made by the Sellers’ Representative with respect to the foregoing described matters on behalf of the Parties Seller as fully and effectively as though each had done, performed, made or executed the same

[SIGNATURE PAGES TO FOLLOW]

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IN WITNESS WHEREOF, Seller and Buyer have executed and delivered this Agreement as of the date first set forth above.

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