THIRDAMENDMENT TO CREDIT AGREEMENT

Exhibit 10.3

Execution Copy

THIRD AMENDMENT TO CREDIT AGREEMENT

This THIRD AMENDMENT TO CREDIT AGREEMENT (“Amendment”), dated as of September 30, 2008, is by and among PINNACLE GAS RESOURCES, INC., a Delaware corporation, the Lenders from time to time party hereto, and THE ROYAL BANK OF SCOTLAND plc, as Administrative Agent and as Issuer.

WHEREAS, the Borrower, the Lenders and the Administrative Agent are parties to that certain Credit Agreement (as amended by that certain Letter Regarding Waiver and Amendment to Credit Agreement dated March 9, 2007 and the Second Amendment to Credit Agreement dated as of July 29, 2008 and as further amended and supplemented from time to time, the “Credit Agreement); and

WHEREAS, the parties hereto desire to amend the Credit Agreement in certain respects as set forth herein;

NOW THEREFORE, in consideration of the premises and the mutual covenants, representations and warranties contained herein, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto hereby agree as follows:

AGREEMENT

Section 1.                                           Definitions.  Capitalized terms used herein but not defined herein shall have the meanings as given them in the Credit Agreement, unless the context otherwise requires.

Section 2.                                           Amendments.

(a)                                 Section 1.1.  Section 1.1 of the Credit Agreement is hereby amended as follows:

(i)                                    The definition of “Alternate Base Rate” is hereby amended and restated in its entirety as follows:

“Alternate Base Rate” means, on any date and with respect to all ABR Loans, a fluctuating rate of interest per annum (rounded upward, if necessary, to the next highest 1/16 of 1%) equal to the highest of the then determinable of

(a)                                 the Base Rate in effect on such day;

(b)                                the Federal Funds Effective Date in effect on such day plus ½ of 1%; and

(c)                                 the sum of 1.00% plus the one-month LIBO Rate as of 11:00 a.m. (London time) on such day.

Changes in the rate of interest on that portion of any Loans maintained as ABR Loans will take effect simultaneously with each change in the Alternate Base Rate.  The Administrative Agent will give notice promptly to the Borrower and the Lenders of changes in the Alternate Base Rate; provided that, the failure to give such notice shall not affect the Alternate Base Rate in effect after such change.”

(ii)                                 the definition of “Applicable Margin” is hereby amended and restated in its entirety as follows:

“Applicable Margin” means, for any day and with respect to all Loans maintained as Eurodollar Loans or ABR Loans, the applicable percentage set forth below corresponding to the Utilization Percentage Share:

If at any time the Borrower fails to deliver a Reserve Report or Probable and Possible Report pursuant to Section 2.8.2 or 2.8.3, then the “Applicable Margin” means the rate per annum set forth on the grid when the Utilization Percentage Share is at its highest level until such time as such Reserve Report and such Probable and Possible Report have been delivered.

(iii)                              The definition of Current Assets is hereby amended and restated in its entirety as follows:

“Current Assets” means, at any date, the current assets of the Borrower and its Consolidated Subsidiaries plus the aggregate Unused Commitments which would be available pursuant to Section 5.1, exclusive of the current portion of the mark-to-market value of assets constituting commodity derivative instruments as reflected on the Borrower’s consolidated balance sheet.

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(iv)                             The definition of Current Liabilities is hereby amended and restated in its entirety as follows:

“Current Liabilities” means, at any date, the current liabilities of the Borrower and its Consolidated Subsidiaries, exclusive of the current portion of the Loans and Letters of Credit hereunder and exclusive of the current portion of the mark-to-market value of liabilities constituting commodity derivative instruments as reflected on the Borrower’s consolidated balance sheet.

(b)                                Section 5.1.2.  Section 5.1.2 of the Credit Agreement is hereby amended and restated in its entirety as follows:

5.1.2                       the fact that, immediately before such requested Credit Extension, no Default shall have occurred and be continuing and that the making of any such Credit Extension will not cause a Default, including, for clarification, the fact that the making of such Credit Extension shall not cause, nor with the passage of time be expected to cause, a breach of the financial covenants included in 7.15.3, 7.15.4, or 7.15.5 as of the time of such Credit Extension and the fact that immediately before the making of such requested Credit Extension, ratio of the Borrower’s Current Assets to its Current Liabilities (as of the time of the request for such Credit Extension) is no less than 1.00 to 1.00.

Section 3.                                           Waiver.  The Administrative Agent and the Lenders hereby waive the requirement in Section 7.15.2 of the Credit Agreement that the Borrower not permit the ratio of its Current Assets to its Current Liabilities to be less than 1.00 to 1.00 for the fiscal quarter ending September 30, 2008.  The waiver in this Section 3 is effective only for the fiscal quarter ending September 30, 2008 and not any other fiscal quarter.

Section 4.                                           Conditions to Effectiveness.  This Amendment shall be deemed effective as of the date hereof following the satisfaction of the following conditions:

(a)                                 the Administrative Agent shall have received counterparts hereof duly executed by the Borrower, the Administrative Agent, and the Required Lenders; and

(b)                                the Administrative Agent shall have received an amendment fee in an amount equal to Thirty-Six Thousand Two Hundred Fifty Dollars ($36,250) for the account of the Administrative Agent.

Section 5.                                           Representations and Warranties.  The Borrower hereby represents and warrants that after giving effect hereto:

(a)                                 the representations and warranties of the Borrower and each Subsidiary contained in the Loan Documents are true and correct in all material respects on and as of the date hereof, other than those representations and warranties that expressly relate solely to a specific earlier date, which shall remain correct in all material respects as of such earlier date;

(b)                                the execution, delivery and performance by the Borrower and each Subsidiary of this Amendment has been duly authorized by all necessary corporate action

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required on their part and this Amendment, along with the Credit Agreement as amended hereby and other Loan Documents, constitutes the legal, valid and binding obligation of each Obligor party thereto enforceable against them in accordance with its terms, except as its enforceability may be affected by the effect of bankruptcy, insolvency, reorganization, moratorium or other similar laws now or hereafter in effect relating to or affecting the rights or remedies of creditors generally;

(c)                                 neither the execution, delivery and performance of this Amendment by the Borrower and each Subsidiary, the performance by them of the Credit Agreement nor the consummation of the transactions contemplated hereby does or shall contravene, result in a breach of, or violate (i) any provision of the Borrower or any Subsidiary’s certificate or articles of incorporation or bylaws or other similar documents, or agreements, (ii) any law or regulation, or any order or decree of any court or government instrumentality, or (iii) any indenture, mortgage, deed of trust, lease, agreement or other instrument to which the Borrower or any of its Subsidiaries is a party or by which the Borrower or any of its Subsidiaries or any of their property is bound, except in any such case to the extent such conflict or breach has been waived herein or by a written waiver document, a copy of which has been delivered to Administrative Agent on or before the date hereof;

(d)                                no Material Adverse Effect has occurred and is continuing; and

(e)                                 no Default or Event of Default has occurred and is continuing.

Section 6.                                           Ratification.

(a)                                 This Amendment shall be deemed to be an amendment to the Credit Agreement, and the Credit Agreement, as hereby amended, and all Obligations in connection therewith, are hereby ratified, approved and confirmed in each and every respect.  On and after the effectiveness of this Amendment in accordance with Section 4 above, each reference in the Credit Agreement to “this Agreement”, “hereunder”, “hereof” or words of like import, referring to the Credit Agreement, and each reference in each other Loan Document to “the Credit Agreement”, “thereunder”, “thereof” or words of like import referring to the Credit Agreement, shall mean and be a reference to the Credit Agreement as amended or otherwise modified by this Amendment.  This Amendment is a Loan Document.

(b)                                The Borrower and each of its Subsidiaries hereby ratifies, approves and confirms in every respect all the terms, provisions, conditions and obligations of each of the Security Documents, including without limitation all Mortgages, Pledge and Security Agreements, and Guaranties, to which it is a party.

Section 7.                                           Costs and Expenses.  As provided in Section 9.4 of the Credit Agreement, the Borrower agrees to reimburse Administrative Agent for all fees, costs, and expenses, including the reasonable fees, costs, and expenses of counsel or other advisors for advice, assistance, or other representation in connection with this Amendment.

Section 8.                                           GOVERNING LAW. THIS AGREEMENT HAS BEEN NEGOTIATED, IS BEING EXECUTED AND DELIVERED, AND WILL BE PERFORMED IN WHOLE OR IN PART, IN THE STATE OF NEW YORK, AND THE

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SUBSTANTIVE LAWS OF SUCH STATE AND THE APPLICABLE FEDERAL LAWS OF THE UNITED STATES OF AMERICA SHALL GOVERN THE VALIDITY, CONSTRUCTION, ENFORCEMENT AND INTERPRETATION OF THE LOAN DOCUMENTS, EXCEPT TO THE EXTENT THE LAWS OF ANY JURISDICTION WHERE COLLATERAL IS LOCATED REQUIRE APPLICATION OF SUCH LAWS WITH RESPECT TO SUCH COLLATERAL.

Section 9.                                           Severability.  Any provision of this Amendment that is prohibited or unenforceable in any jurisdiction shall, as to such provision and such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions of this Amendment or affecting the validity or enforceability of such provision in any other jurisdiction.

Section 10.                                     Counterparts.  This Amendment may be executed in any number of counterparts, all of which taken together shall constitute one and the same instrument, and any party hereto may execute this Amendment by signing one or more counterparts.  Any signature hereto delivered by a party by facsimile transmission shall be deemed to be an original signature hereto.

Section 11.                                     No Waiver.  Except as expressly set forth in this Amendment, the execution, delivery and effectiveness of this Amendment shall not operate as a waiver of any default of the Borrower or any other Obligor or any right, power or remedy of the Administrative Agent or the other Secured Parties under any of the Loan Documents, nor constitute a waiver of any provision of any of the Loan Documents.

Section 12.                                     Successors and Assigns.  This Amendment shall be binding upon the Borrower and its successors and permitted assigns and shall inure, together with all rights and remedies of each Lender hereunder, to the benefit of each Lender and the respective successors, transferees and assigns.

Section 13.                                     Entire Agreement.  THIS AMENDMENT, THE CREDIT AGREEMENT AND THE OTHER LOAN DOCUMENTS CONSTITUTE THE ENTIRE AGREEMENT BETWEEN THE PARTIES HERETO WITH RESPECT TO THE SUBJECT HEREOF AND SHALL SUPERSEDE ANY PRIOR AGREEMENT BETWEEN THE PARTIES HERETO, WHETHER WRITTEN OR ORAL, RELATING TO THE SUBJECT HEREOF.  FURTHERMORE, IN THIS REGARD, THIS AGREEMENT REPRESENTS THE FINAL AGREEMENT AMONG THE PARTIES THERETO AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT ORAL AGREEMENTS OF SUCH PARTIES.

THERE ARE NO UNWRITTEN ORAL AGREEMENTS AMONG SUCH PARTIES.

[Signature Pages Follow]

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be duly executed and delivered by their respective duly authorized officers as of the date hereof.