THIRD AMENDMENT TO THE CREDIT AGREEMENT dated as of October 20, 2015 among ENERGEN CORPORATION, as Borrower, WELLS FARGO BANK, NATIONAL ASSOCIATION, as Administrative Agent, THE GUARANTOR SIGNATORY HERETO, and THE LENDERS SIGNATORY HERETO THIRD AMENDMENT TO CREDIT AGREEMENT

This THIRD AMENDMENT TO THE CREDIT AGREEMENT (this “Third Amendment”), dated as of October 20, 2015 (the “Third Amendment Effective Date”), is among ENERGEN CORPORATION, a corporation formed under the laws of the State of Alabama (“Borrower”); the undersigned guarantor (the “Guarantor”, and together with Borrower, the “Credit Parties”); each of the Lenders party hereto; and WELLS FARGO BANK, NATIONAL ASSOCIATION, as administrative agent for the Lenders (in such capacity, together with its successors in such capacity, “Administrative Agent”).

A.    Borrower, Administrative Agent and the Lenders are parties to that certain Credit Agreement dated as of September 2, 2014 (as heretofore amended, modified, supplemented or restated, the “Credit Agreement”), pursuant to which the Lenders have, subject to the terms and conditions set forth therein, made certain credit available to and on behalf of Borrower.

B.    The parties hereto desire to enter into this Third Amendment to amend Section 2.07(e) of the Credit Agreement as set forth herein, to be effective as of the Third Amendment Effective Date.

C.    The Lenders party hereto also desire to complete the October 1, 2015 Scheduled Redetermination as set forth herein.

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

Section 1.Defined Terms. Each capitalized term which is defined in the Credit Agreement, but which is not defined in this Third Amendment, shall have the meaning ascribed to such term in the Credit Agreement (as amended hereby). Unless otherwise indicated, all section references in this Third Amendment refer to the Credit Agreement.

Section 2.    Amendment to Section 2.07(e). In reliance on the representations, warranties, covenants and agreements contained in this Third Amendment, and subject to the satisfaction of the conditions precedent set forth in Section 4 hereof, Section 2.07(e) of the Credit Agreement is hereby amended, effective as of the Third Amendment Effective Date, to replace the reference to “October 1, 2015” appearing in clause (y) of the third sentence of Section 2.07(e), with “April 1, 2016”.

Section 3.    Borrowing Base Redetermination; Reduction of Aggregate Commitment.

3.1    Subject to the satisfaction of the conditions precedent set forth in Section 4 hereof, Administrative Agent and the Lenders hereby agree that for the period from and including the Third Amendment Effective Date to but excluding the next Redetermination Date, the amount of the

Borrowing Base shall be equal to $1,400,000,000 (the “October 2015 Redetermination”). Administrative Agent, the Lenders and Borrower agree that the foregoing constitutes the October 1, 2015 Scheduled Redetermination and that this Third Amendment shall constitute the New Borrowing Base Notice with respect to such Scheduled Redetermination. Notwithstanding the foregoing, the Borrowing Base may be subject to further redeterminations and adjustments from time to time pursuant to Section 2.07 or Section 8.12(c).

3.2    Concurrently with the October 2015 Redetermination, the Aggregate Commitment shall be reduced (ratably among the Lenders in accordance with each Lender’s Applicable Percentage) pursuant to Section 2.06(b)(iii), so that the Aggregate Commitment equals $1,400,000,000 (and Annex I is hereby deemed amended to reflect the reduction to each Lender’s Commitment and the Aggregate Commitment).

Section 4.    Conditions Precedent. The effectiveness of this Third Amendment is subject to the following:

4.1    Administrative Agent shall have received counterparts of this Third Amendment from the Credit Parties and the Required Lenders.

4.2    Administrative Agent shall have received such other documents as Administrative Agent or special counsel to Administrative Agent may reasonably request.

Administrative Agent shall notify Borrower and the Lenders of the effectiveness of this Third Amendment, and such notice shall be conclusive and binding.

Section 5.    Representations and Warranties; Etc. Each Credit Party hereby affirms: (a) that as of the date hereof, the representations and warranties of Borrower and Guarantor set forth in each Loan Document are true and correct in all material respects (or, if qualified by materiality or Material Adverse Effect, in all respects), except to the extent any such representations and warranties are expressly limited to an earlier date, in which case, on and as of the date hereof, such representations and warranties continue to be true and correct in all material respects (or, if qualified by materiality or Material Adverse Effect, in all respects) as of such specified earlier date and (b) that as of the date hereof, no Default or Event of Default has occurred and is continuing or would result from this Third Amendment.

Section 6.    Miscellaneous.

6.1    Confirmation and Effect. The provisions of the Credit Agreement (as amended by this Third Amendment) shall remain in full force and effect in accordance with its terms following the effectiveness of this Third Amendment. Each reference in the Credit Agreement to “this Agreement”, “hereunder”, “hereof’, “herein”, or words of like import shall mean and be a reference to the Credit Agreement as amended hereby, and each reference to the Credit Agreement in any other document, instrument or agreement executed and/or delivered in connection with the Credit Agreement shall mean and be a reference to the Credit Agreement as amended hereby. The execution, delivery and effectiveness of this Third Amendment shall not, except as expressly provided herein,

operate as a waiver of any right, power or remedy of any Lender or the Administrative Agent under any of the Loan Documents, nor constitute a waiver of any provision of any of the Loan Documents.

6.2    Ratification and Affirmation of Credit Parties. Each of the Credit Parties hereby expressly (a) acknowledges the terms of this Third Amendment, (b) ratifies and affirms its obligations under the Guaranty Agreement and the other Loan Documents to which it is a party, (c) acknowledges, renews and extends its continued liability under the Guaranty Agreement and the other Loan Documents to which it is a party (in each case, as amended hereby), and (d) acknowledges and confirms that the amendments contemplated hereby shall not limit or impair any Liens securing the Indebtedness, each of which are hereby ratified, affirmed and extended to secure the Indebtedness after giving effect to this Third Amendment.

6.3    Counterparts. This Third Amendment may be executed by one or more of the parties hereto in any number of separate counterparts, and all of such counterparts taken together shall be deemed to constitute one and the same instrument. Delivery of this Third Amendment by facsimile or electronic (e.g. pdf) transmission shall be effective as delivery of a manually executed original counterpart hereof.

6.4    No Oral Agreement. This written Third Amendment, the Credit Agreement and the other Loan Documents executed in connection herewith and therewith represent the final agreement between the parties and may not be contradicted by evidence of prior, contemporaneous, or unwritten oral agreements of the parties. There are no subsequent oral agreements between the parties.

6.5    Governing Law. This Third Amendment (including, but not limited to, the validity and enforceability hereof) shall be governed by, and construed in accordance with, the laws of the State of New York.

6.6    Severability. Any provision of this Third Amendment which is prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions hereof, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision in any other jurisdiction.

6.7    Loan Document. This Third Amendment shall constitute a “Loan Document” for all purposes under the other Loan Documents.

IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment to be duly executed effective as of the date first written above.

BORROWER:         ENERGEN CORPORATION

By:    /S/ CHARLES W. PORTER, JR.    

Name:    Charles W. Porter, Jr.

GUARANTOR:                ENERGEN RESOURCES CORPORATION

By:    /S/ CHARLES W. PORTER, JR.    

Name:    Charles W. Porter, Jr.

By:    /S/ LILA JORDAN    

By:    /S/ MICHAEL CLAYBORNE    

By:    /S/ DOROTHY MARCHAND    

By:    /S/ JO LINDA PAPADAKIS    

By:    /S/ WILLIAM A. PHILIPP    

By:    /S/ MARK OBERREUTER    

By:    /S/ DARLA MAHONEY    

By:    /S/ RICHARD ANTL    

By:    /S/ LEON MO    

By:    /S/ JONATHAN LUCHANSKY    

By:    /S/ JAMES D. WEINSTEIN    

By:    /S/ NICHOLAS T. HANFORD    

By:    /S/ RYAN AMAN    

By:    /S/ MELISSA GUZMANN    

By:    /S/ ASULV TVELT    

By:    /S/ JOE HYKLE    

By:    /S/ EVANS SWANN    

By:    /S/ RAYAN KARIM    

By:    /S/ JOHN KRENGER    

By:    /S/ DOREEN BARR    

By:    /S/ WARREN VAN HEYST    

By:    /S/ LARRY HAYES    

By:    /S/ JOSEPH KEENER    

By:    /S/ MAY HUANG    

By:    /S/ MATTHEW T. MEYERS