AGREEMENT AND AMENDMENT NO. 13

Exhibit 10.1

AGREEMENT AND AMENDMENT NO. 13

This AGREEMENT AND AMENDMENT NO. 13 (“Agreement”) dated as of February 3, 2016 (“Amendment No. 13 Effective Date”), is among Alta Mesa Holdings, LP, a Texas limited partnership (the “Borrower”), the affiliates of the Borrower party hereto (the “Guarantors”), the Lenders (as defined below), and Wells Fargo Bank, N.A., as administrative agent for such Lenders (in such capacity, the “Administrative Agent”) and as issuing lender (in such capacity, the “Issuing Lender”).

RECITALS

A. Reference is made to that certain Sixth Amended and Restated Credit Agreement dated as of May 13, 2010, among the Borrower, the lenders party thereto from time to time (the “Lenders”), the Administrative Agent, and the Issuing Lender, as heretofore amended (as so amended, the “Credit Agreement”).

B. The parties hereto wish to, subject to the terms and conditions of this Agreement, make certain amendments to the Credit Agreement as set forth herein.

NOW THEREFORE, in consideration of the benefits to be derived by the parties hereto and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

Section 1. Defined Terms; Other Provisions. As used in this Agreement, each of the terms defined in the opening paragraph and the Recitals above shall have the meanings assigned to such terms therein. Each term defined in the Credit Agreement and used herein without definition shall have the meaning assigned to such term in the Credit Agreement, unless expressly provided to the contrary. Article, Section, Schedule, and Exhibit references are to Articles and Sections of and Schedules and Exhibits to this Agreement, unless otherwise specified. The words “hereof”, “herein”, and “hereunder” and words of similar import when used in this Agreement shall refer to this Agreement as a whole and not to any particular provision of this Agreement. The term “including” means “including, without limitation,”. Paragraph headings have been inserted in this Agreement as a matter of convenience for reference only and it is agreed that such paragraph headings are not a part of this Agreement and shall not be used in the interpretation of any provision of this Agreement.

Section 2. Amendments to Credit Agreement.

  (a) Section 1.01 (Certain Defined Terms) of the Credit Agreement is hereby amended by adding the following new defined terms to appear where alphabetically appropriate:

“Amendment No. 13 Effective Date” means February 3, 2016.

“Available Funds” means the aggregate of all funds held in deposit accounts owned by, or held for the benefit of, the Borrower or any Restricted Subsidiary (other than amounts on deposit in or credited to (i) the Cash Collateral Account, (ii) any escrow accounts and third party cash pledges or deposits made in the ordinary course of business, and (iii) the Controlled Account).

“Bayou City JDA” means the Joint Development Agreement between BCE-STACK Development LLC and Oklahoma Energy Acquisitions, LP in such form and substance substantially similar to the draft thereof provided to the Administrative Agent on January 6, 2016 or such other form and substance reasonably acceptable to the Administrative Agent.

“Common Equity Issuance Proceeds” means (a) with respect to any issuance of common Equity Interests of the Borrower, all cash proceeds received by the Borrower from such equity issuance (other than from any other Loan Party or Subsidiary thereof) after payment of, or provision for, all underwriter fees and expenses, SEC and blue sky fees, printing costs, fees and expenses of accountants, lawyers and other professional advisors, brokerage commissions and other out-of-pocket fees and expenses actually incurred in connection with such equity issuance, and (b) with respect to existing Equity Interests, cash contributions made to the Borrower from the holders of its Equity Interests on account of common equity.

“Control Agreement” means a blocked account control agreement among the Borrower, the Administrative Agent, the Second Lien Agent, Wells Fargo Bank, N.A. as the depository bank, and, upon the incurrence of Third Lien Debt, an entity serving in the capacity as the “collateral trustee”, “collateral agent”, or “administrative agent”, or any similar role under the Third Lien Loan Documents, in such form reasonably acceptable to the parties thereto which agreement, among other things, restricts access to the covered account and the funds therein consistent with Section 6.25 below.

“Controlled Cash Collateral” means, as of any date of determination, the amount of readily and immediately available cash held in the Controlled Account and subject to the Control Agreement.

“Controlled Account” means a designated and blocked deposit account in the name of the Borrower with Wells Fargo Bank, N.A., as depositary bank, which is subject to the Control Agreement.

“Junior Debt Payoff” means the occurrence of each of the following: (a) the termination of all commitments or other obligations to extend credit under the Second Lien Credit Agreement, (b) the payment in full of all Second Lien Debt and all Third Lien Debt and (c) termination of the Intercreditor Agreement.

“Leverage Ratio” means, as of the last day of any fiscal quarter, the ratio of (a) all Debt (other than obligations under Hedge Contracts) of the Borrower and its Restricted Subsidiaries as of such day minus Controlled Cash Collateral as of such day to (b) Adjusted EBITDAX.

“Permitted Exchange/Payment of Senior Unsecured Notes” means (a) one or more exchanges of outstanding Senior Unsecured Notes solely for Third Lien Debt and the payment of interest accrued on the Senior Unsecured Notes tendered in such exchange through the settlement date of such exchange, and (b) one or more repurchases of Senior Unsecured Notes through the open market, privately negotiated transactions or a tender offer but effected solely with Permitted Proceeds and the payment of interest accrued on the Senior Unsecured Notes repurchased through the settlement date of such repurchase; provided that, in each case under clause (a) and clause (b) above, each such transaction shall not constitute a Permitted Exchange/Payment of Senior Unsecured Notes unless each of the following conditions are satisfied as to such transaction: (i) the tendered or repurchased Senior Unsecured Notes must be retired concurrently with, or immediately after, such exchange or repurchase, (ii) the net Interest Expense for all obligations of the Borrower and its Subsidiaries for the 12-month period after the consummation of such transaction, after giving pro forma effect to such transaction, must

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be no greater than the net Interest Expense for all obligations of the Borrower and its Subsidiaries for such period had such transaction not occurred and, at least three Business Days prior to effecting such transaction the Borrower shall have delivered to the Administrative Agent an officer’s certificate executed by a Responsible Officer of the Borrower certifying a calculation of such net Interest Expense before and after giving effect to such transaction in such detail acceptable to the Administrative Agent, (iii) the exchange rate or purchase price, as applicable, for such transaction shall be acceptable to the Administrative Agent, and (iv) no Default has occurred or is continuing at the time of such exchange or repurchase.

“Permitted Proceeds” means Common Equity Issuance Proceeds in an aggregate amount not in excess of $50,000,000.

“Third Lien Debt” means Additional Subordinated Debt that is secured by a third priority Lien as of the time of inception.

“Third Lien Loan Documents” means the agreements and instruments governing the Third Lien Debt, the promissory notes executed and delivered pursuant to such agreements and instruments, and each other agreement, instrument, or document executed by the Borrower or any other Loan Party or any of their Responsible Officers in connection with the Third Lien Debt.

  (b) Section 1.01 (Certain Defined Terms) of the Credit Agreement is hereby amended by replacing the defined terms “Additional Subordinated Debt”, “First Lien Cap Certificate”, “Intercreditor Agreement”, “Loan Documents,” “Material Disposition”, “Refinancing Debt”, “Restricted Payment”, and “Triggering Event” in their entirety with the following corresponding terms:

“Additional Subordinated Debt” means any term (and not “revolving”) indebtedness of the Borrower for borrowed money, including any such Debt evidenced by bonds, debentures, notes or other similar instruments, or any redeemable preferred equity of the Borrower (but excluding the Second Lien Debt), in any event, issued after the Effective Date and only to the extent such Debt complies with all of the following requirements:

(a) the agreements and instruments governing such Debt shall not contain (i) any affirmative or negative covenant (including financial covenants) that is materially more restrictive than those set forth in this Agreement; provided that the inclusion of any covenant that is customary with respect to such type of Debt and that is not found in this Agreement shall not be deemed to be more restrictive for purposes of this clause (a)(i), (ii) any restriction on the ability of the Borrower or any of its Restricted Subsidiaries to amend, modify, restate or otherwise supplement this Agreement or the other Loan Documents except as provided in the Intercreditor Agreement, (iii) any restrictions on the ability of any Subsidiary of the Borrower to guarantee the Obligations (as such Obligations may be amended, supplemented, modified, or amended and restated but not increased), provided that a requirement that any such Subsidiary also guarantee such Debt shall not be deemed to be a violation of this clause (ii), (iv) any restrictions on the ability of any Subsidiary or the Borrower to pledge assets as collateral security for the Obligations (as such Obligations may be amended, supplemented, modified, or amended and restated but not increased) other than, with respect to such Debt that is secured, any such restrictions which are otherwise satisfactory to the Administrative Agent and the Required Lenders; provided that, in any event, (x) a requirement that such Debt be secured in compliance with clause (b) below shall not be deemed to be a violation of this

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clause (iv) and (y) a requirement that such Debt be secured by the same assets that serve as collateral security for the Obligations shall not be deemed to be a violation of this clause (iv), (v) any cap or restrictions on the ability of any Subsidiary or the Borrower to incur Debt under this Agreement or any other Loan Document, except as provided in an applicable intercreditor agreement; and (vi) a scheduled maturity date that is earlier than the later of (x) October 13, 2018 and (y) the date 180 days after the Maturity Date in effect at the time such Debt is incurred, or (vii) any amortization or other scheduled principal payments or, except as permitted by the Intercreditor Agreement, any mandatory principal payments, other than at the scheduled maturity thereof;

(b) if such Debt is secured, the Liens securing such Debt covers the same assets which serve as collateral for the Obligations pursuant to the Loan Documents and are subordinated to the Liens securing the Obligations pursuant to an intercreditor agreement the terms of which are satisfactory to the Administrative Agent and the Required Lenders;

(c) if such Debt is preferred equity, such Debt shall not be secured and shall not, by its terms (or by the terms of any security or instrument into which it is convertible or for which it is exchangeable or exercisable), or upon the happening of any event, (i) mature (excluding any maturity as the result of an optional redemption by the Borrower) or be mandatorily redeemable, pursuant to a sinking fund obligation or otherwise, or be redeemable at the option of the holder thereof, in whole or in part, on or prior to the later of (x) October 13, 2018 and (y) the first anniversary of the Maturity Date in effect at the time such Debt is incurred, (ii) be convertible into or exchangeable or exercisable (unless at the sole option of the Borrower) for (A) debt securities or other Debt or (B) any Equity Interests with terms set forth in the immediately preceding clause (ii), in each case at any time on or prior to the first anniversary of the Maturity Date in effect at the time such Debt is incurred, or (iii) contain any repurchase or payment obligation which may come into effect prior to the first anniversary of the Maturity Date in effect at the time such Debt is incurred;

(d) the incurrence of such Debt shall not result in an increase in the Borrower’s Interest Expense;

(e) on the date of incurrence of such Debt, immediately before and after giving effect to such incurrence and any concurrent repayment of Debt with the proceeds thereof, the Borrower is in compliance, on a pro forma basis, with Sections 6.17, 6.18 and 6.19 of this Agreement; and

(f) no Default or Event of Default exists on the date of incurrence of such Debt or will occur immediately after, and as a result of, the issuance of such Debt.

“First Lien Cap Certificate” means a certificate executed by a Responsible Officer of the Borrower, in form and with detail satisfactory to the Administrative Agent which certificate shall set forth a detailed calculation of the “First Lien Cap” as defined in the Intercreditor Agreement, including (a) the total net present value (discounted at 9% per annum) of the PDP Reserves, PDNP Reserves and PUD Reserves, calculated separately, and attributable to the Borrower’s and its Restricted Subsidiaries’ Oil and Gas Properties, as such values are reflected in such Engineering Report, (b) a calculation of such net present value after taking into account the PDNP Reserve and PUD Reserve limitation set forth in the Intercreditor Agreement, and (c) the aggregate outstanding principal amount of the Second Lien Debt and Third Lien Debt on the date of such certification.

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“Intercreditor Agreement” means, as applicable, (a) until the incurrence of the Third Lien Debt, that certain Intercreditor Agreement dated as of the Amendment No. 11 Effective Date among the Borrower, the Administrative Agent, and the Second Lien Agent, and (b) from and after the incurrence of the Third Lien Debt, an intercreditor agreement applicable to the Obligations, the Second Lien Debt and the Third Lien Debt which amends and restates that certain Intercreditor Agreement dated as of the Amendment No. 11 Effective Date among the Borrower, the Administrative Agent, the Second Lien Agent and an entity serving in the capacity as the “collateral trustee”, “collateral agent”, or “administrative agent”, or any similar role under the Third Lien Loan Documents, in form and substance reasonably satisfactory to the Administrative Agent and the Required Lenders, as the same may from time to time be amended, modified, supplemented or restated as permitted herein.

“Loan Documents” means this Agreement, the Notes, the Letter of Credit Documents, the Guaranties, the Security Instruments, the Intercreditor Agreement, the Fee Letters, the Control Agreement and each other agreement, instrument, or document executed by the Borrower or any of its Restricted Subsidiaries or any of their officers at any time in connection with this Agreement or any other Loan Document.

“Material Disposition” means “Material Disposition” as defined in the Second Lien Credit Agreement or such other Disposition, if any, that triggers a mandatory prepayment of principal and associated interest and fees under the Second Lien Credit Agreement or any Third Lien Loan Document.

“Refinancing Debt” means Senior Unsecured Notes but only to the extent the proceeds thereof refinance (a) the Second Lien Debt, (b) the Third Lien Debt, (c) Senior Unsecured Notes outstanding on the Amendment No. 11 Effective Date, or (d) Refinancing Debt which refinanced the Debt described in the foregoing clause (a), (b) or (c).

“Triggering Event” means (a) the Disposition of Oil and Gas Properties of the Borrower or any Restricted Subsidiary that have a positive value in the most recently delivered Engineering Report or in the Engineering Report evaluated for the then effective Borrowing Base or the Disposition of the Equity Interests issued by any Restricted Subsidiary that owns such Oil and Gas Properties and (b) the novation, assignment, unwinding, termination, or amendment of a hedge position or Hedge Contract considered by the Administrative Agent in determining the then effective Borrowing Base to the extent such hedge position or Hedge Contract is not immediately replaced by a new hedge position or new Hedge Contract (or in the case of an amendment, an amended hedge position or amended Hedge Contract) which would result in an equal or greater value to the Borrowing Base (as determined by the Administrative Agent in its sole discretion).

(c) Section 1.01 (Certain Defined Terms) of the Credit Agreement is hereby further amended by replacing clause (d) in the definition of “Change in Control” with the following:

(d) any “change in control” (as set forth in the Second Lien Credit Agreement, any document governing any Additional Subordinated Debt or in the indenture governing the Senior Unsecured Notes) occurs that obligates the Borrower or any other Loan Party to repurchase, redeem or repay all or any part of the Debt provided for therein.

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(d) Each reference to “Second Lien Debt Payoff” found in Section 2.02 (Borrowing Base) of the Credit Agreement, Section 2.06 (Repayment of Advances; Mandatory Prepayment of Advances) of the Credit Agreement, and Section 3.02 (Conditions Precedent to All Borrowings) is replaced with a reference to “Junior Debt Payoff”.

(e) Section 2.02(e) (Mandatory Reductions in the Borrowing Base) of the Credit Agreement is hereby amended by replacing clause (ii), (iii) and clause (iv) in their entirety with the following corresponding clause (ii), (iii) and clause (iv):

(ii) Effective immediately upon the issuance of any Additional Subordinated Debt (other than Senior Unsecured Notes and Additional Subordinated Debt to the extent the proceeds thereof are applied to effect the Permitted Exchange/Payment of Senior Unsecured Notes) by the Borrower or any Restricted Subsidiary, the Borrowing Base shall automatically reduce on the effective date of such issuance by an amount equal to 25% of (A) the principal amount of such Additional Subordinated Debt minus (B) the principal amount of Second Lien Debt repaid with the proceeds of such Additional Subordinated Debt (other than repayments of any increases in principal of Second Lien Debt effected after the Amendment No. 11 Effective Date and any interest accrued on such increased principal amount).

(iii) if a Triggering Event occurs which results in the aggregate amount of all Triggering Events (including such Triggering Event) effected during the six month period between scheduled redeterminations of the Borrowing Base to exceed 5% of the Borrowing Base then in effect, then effective immediately upon the occurrence of such Triggering Event and each subsequent Triggering Event until the next scheduled redetermination of the Borrowing Base occurs, the Borrowing Base shall automatically reduce on the date such Triggering Event and such subsequent Triggering Event is effected by an amount equal to (A) in the case of a Disposition of Oil and Gas Properties (or any Restricted Subsidiary that owns Oil and Gas Properties), the value, if any, assigned such Oil and Gas Properties under the then effective Borrowing Base, as reasonably determined by the Administrative Agent, and (B) in the case of a hedge position or Hedge Contract that has been novated, assigned, unwound, terminated, or amended, the value, if any, assigned such hedge position or Hedge Contract under the then effective Borrowing Base, as reasonably determined by the Administrative Agent;

(iv) [Reserved.]

(f) Section 4.17 (Liens; Titles, Leases, Etc.) of the Credit Agreement is hereby amended by replacing the parenthetical found therein with the following:

(other than this Agreement, the Security Instruments, the Second Lien Loan Documents and the Third Lien Loan Documents)

(g) Article IV (Representations and Warranties) of the Credit Agreement is hereby amended by adding a new Section 4.22 to the end thereof:

Section 4.22 Draws From the Controlled Account. Each request for a withdrawal of funds from such Controlled Account made by the Borrower shall be deemed to constitute a representation and warranty by the Borrower under this Section 4.22 that the Borrower is in compliance with Section 6.25 as to such withdrawal of funds.

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(h) Section 5.06(p) (Notices Under Other Loan Agreements) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

(p) Notices and Etc. Under Other Loan Agreements. Promptly after the furnishing thereof, copies of any statement, report or notice furnished to any Person pursuant to the terms of any indenture, loan or credit or other similar agreement (including any Second Lien Loan Document and any Third Lien Loan Document) relating to Debt of the Borrower or its Restricted Subsidiaries in an aggregate principal amount in excess of $5,000,000, other than this Agreement and not otherwise required to be furnished to the Lenders pursuant to any other provision of this Section 5.06;

(i) Section 5.08 (Agreement to Pledge) of the Credit Agreement is hereby amended by replacing clause (iii) therein in its entirety with the following:

Section 5.08 Agreement to Pledge. The Borrower shall, and shall cause each Restricted Subsidiary to, grant to the Administrative Agent an Acceptable Security Interest in any Property of the Borrower or any Restricted Subsidiary now owned or hereafter acquired promptly after receipt of a written request from the Administrative Agent; provided that (a) in no event shall the Administrative Agent be permitted to request or the Borrower be required to grant an Acceptable Security Interest in any Oil and Gas Properties that exceeds 90% (by value) (or such greater percentage if required under any Second Lien Loan Document or any Third Lien Loan Document) of all of the Borrower’s and its Restricted Subsidiaries’ Proven Reserves and Oil and Gas Properties, and (b) the Borrower shall cause the Administrative Agent to, at all times and without any requirement of a written request from the Administrative Agent, have an Acceptable Security Interest in at least 90% (by value) (or such greater percentage if required under any Second Lien Loan Document or any Third Lien Loan Document) of all of the Borrower’s and its Restricted Subsidiaries’ Proven Reserves and Oil and Gas Properties.

(a) Section 6.01 (Liens, etc.) of the Credit Agreement is hereby amended by replacing clause (b) in its entirety with the following:

(b) Liens securing the Second Lien Debt and Liens securing the Third Lien Debt so long as (i) the creation, incurrence, assumption or existence of such Liens is permitted under the Intercreditor Agreement, (ii) before and after giving effect to the creation, incurrence, assumption or existence of any such Lien, the Borrower is in compliance with Section 6.24, and (iii) such Second Lien Debt and such Third Lien Debt is permitted under Section 6.02 below;

(b) Section 6.02 (Debts, Guaranties, and Other Obligations) of the Credit Agreement is hereby amended by replacing clauses (i) and (k) therein in their entirety with the following corresponding clauses (i) and (k):

(i) the Initial Second Lien Debt;

(k) Additional Subordinated Debt of the Borrower (other than Senior Unsecured Notes) and the guaranties given by Restricted Subsidiaries with respect thereto (other than guaranties of Additional Subordinated Debt in the form of preferred equity); provided that, 100% of the proceeds of such Additional Subordinated Debt are applied to effect a Permitted Exchange/Payment of Senior Unsecured Notes;

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(c) Section 6.03 (Agreements Restricting Liens and Distributions) of the Credit Agreement is hereby amended by replacing the parenthetical found therein with the following:

(other than this Agreement and the Security Instruments, the Second Lien Loan Documents, the Third Lien Loan Documents and the Senior Unsecured Notes)

(d) Section 6.04 (Merger or Consolidation; Asset Sales; Hedge Terminations) of the Credit Agreement is hereby amended by replacing clause (b)(iv) therein in its entirety with the following:

(iv) if no Event of Default then exists or would result therefrom, (A) the Disposition of Property which does not constitute Proven Reserves and does not constitute Collateral or is not otherwise required under this Agreement to be Collateral; and (B) the Disposition of Oil and Gas Properties which do not constitute Proven Reserves and are Disposed of pursuant to the Bayou City JDA under which such applicable third party is obligated to provide the necessary fundings to drill, complete or equip wells pertaining to such Oil and Gas Properties (it being understood and agreed that the Administrative Agent may, pursuant to Section 8.08(b) below, provide lien releases applicable to such Oil and Gas Properties in advance of actual Disposition thereof under the Bayou City JDA);

(e) Section 6.05 (Restricted Payments) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

Section 6.05 Restricted Payments. The Borrower shall not, nor shall it permit any of its Restricted Subsidiaries to, make any Restricted Payments, except that if no Default or Event of Default has occurred both before and after giving effect to the making of such Restricted Payment, (a) the Restricted Subsidiaries may make Restricted Payments to the Borrower, (b) to the extent permitted under the Second Lien Credit Agreement and the Third Lien Loan Documents, the Borrower may make Restricted Payments to its Equity Interest holders in an amount equal to the income tax liabilities of such Person attributable to the earnings of the Borrower, (c) in addition to the foregoing permitted distribution for tax liabilities, the Borrower may make Restricted Payments to AMIH on account of Equity Interests for purposes of AMIH paying interest it owes under the Highbridge Note Purchase Agreement so long as (i) the aggregate amount of all such Restricted Payments under this clause (c) shall not to exceed the aggregate amount of cash contribution made by AMIH to Borrower on account of Equity Interests since the Amendment No. 7 Effective Date, (ii) before and after giving effect to such Restricted Payment, Availability is equal to or greater than 20% of the Borrowing Base then in effect, and (iii) such Restricted Payments are permitted under the Second Lien Credit Agreement and the Third Lien Loan Documents and (d) the Borrower may make Restricted Payments to the Ellis Entities (as defined in the Agreement Regarding Special Distributions) pursuant to the Agreement Regarding Special Distributions in an aggregate amount not to exceed $516,487.99.

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(f) Section 6.17 (Current Ratio) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

Section 6.17 Current Ratio. The Borrower shall not permit the ratio of, as of the last day of each fiscal quarter of the Borrower, beginning with the fiscal quarter ending June 30, 2010, the Borrower’s and its consolidated Restricted Subsidiaries’ (it being understood that no amounts of the Unrestricted Subsidiaries of the Borrower shall be taken into account in calculating this ratio) (a) consolidated current assets to (b) consolidated current liabilities, to be less than 1.00 to 1.00. For purposes of this calculation (i) “current assets” shall include, as of the date of calculation, the Unused Commitment Amount (but only to the extent the Borrower is able to borrow under this Agreement and be pro forma compliance with its financial covenants herein) but shall exclude any asset representing a valuation account arising from the application of SFAS 133 or 143, and (ii) “current liabilities” shall exclude, as of the date of calculation, the current portion of long–term Debt existing under this Agreement, the Second Lien Credit Agreement or any Third Lien Loan Document, and any liabilities representing a valuation account arising from the application of SFAS 133 and 143.

(g) Section 6.18 (Leverage Ratio) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

Section 6.18 Leverage Ratio. The Borrower shall not permit Leverage Ratio to exceed (a) 4.00 to 1.00 as of the end of each fiscal quarter ending December 31, 2015 and March 31, 2016, (b) 4.50 to 1.00 as of the end of each fiscal quarter ending June 30, 2016 and September 30, 2016 and (c) 4.00 to 1.00 as of the end of each fiscal quarter ending on or after December 31, 2016.

(h) Section 6.23 (Additional Subordinated Debt) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

Section 6.23 Additional Subordinated Debt. The Borrower shall not, nor shall it permit any of its Restricted Subsidiaries to (a) make any payments on account of principal (whether by redemption, purchase, retirement, defeasance, set-off or otherwise), interest, premiums and fees in respect of any Senior Unsecured Notes or any other Additional Subordinated Debt prior to the scheduled maturity thereof in any manner, or make any payment in violation of any subordination term applicable thereto, except that, as to Senior Unsecured Notes, the Borrower may effect the Permitted Exchange/Payment of Senior Unsecured Notes or (b) amend, supplement or otherwise modify the terms of the Third Lien Debt if such amendment, supplement or modification would violate the Intercreditor Agreement.

(i) Section 6.24 (Additional Liens) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

Section 6.24 Additional Liens. No Loan Party shall, nor shall any Loan Party permit any of its Subsidiaries to, grant a Lien on any Property to secure any Debt under the Second Lien Loan Documents (except for such Liens which were permitted to be granted on or before the Amendment No. 11 Effective Date) or any Additional Subordinated Debt without first (a) giving fifteen days’ prior written notice to the Administrative Agent thereof and (b) granting to the Administrative Agent to secure the Obligations an Acceptable Security Interest in the same Property pursuant to Security Instruments in form and substance satisfactory to the Administrative Agent. In connection therewith, each Loan Party shall, or shall cause its Subsidiaries to, execute and deliver such other additional closing documents, certificates and legal opinions as may reasonably be requested by the Administrative Agent.

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(j) Article VI (Negative Covenants) of the Credit Agreement is hereby amended by adding a new Section 6.25 to the end thereof:

Section 6.25 Controlled Account; Withdrawals; Sweeps.

(a) The Borrower shall not request that any Advances be made hereunder on or after the Amendment No. 13 Effective Date or accept the proceeds of any such Advance unless the proceeds of such Advances are deposited into the Controlled Account; provided that from the Amendment No. 13 Effective Date until the date the Control Agreement is entered into and subject to the other terms and conditions set forth herein, the Borrower may request that Advances in an amount not to exceed $15,000,000 in the aggregate be made hereunder and the Borrower may accept the proceeds of such Advances. The Borrower shall not request that the Administrative Agent direct a withdrawal from the Controlled Account unless (i) on and as of each date on which any funds are withdrawn from the Controlled Account (A) all representations and warranties contained above in Article IV and all representations and warranties contained in the Security Instruments, the Guaranties, and each of the other Loan Documents are true and correct in all material respects (except that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof) on and as of the date of such withdrawal and to the application of such funds, as though made on and as of such date (except in the case of representations and warranties which are made solely as of an earlier date or time, which representations and warranties shall be true and correct in all material respects as of such earlier date or time, except that such materiality qualifier shall not be applicable to any representations and warranties that already are qualified or modified by materiality in the text thereof); (B) no Default has occurred and is continuing or would result from the application of such funds; (C) for the avoidance of doubt, such funds will be used only to the extent the proceeds of any Advance could be used under this Agreement, and (D) the Borrower would be in pro forma compliance with Section 6.17 and Section 6.18 as of the most recent fiscal quarter end for which financial statements have been delivered to the Administrative Agent after giving effect to such withdrawal of funds; (ii) the Borrower has delivered to the Administrative Agent an officer’s certificate executed by a Responsible Officer of the Borrower certifying that the Borrower would be in compliance under this Section 6.25 and (iii) the amount of each withdrawal from the Controlled Account is not less than $5,000,000.

(b) On the 1^st day and the 15^th day of each calendar month, if Available Funds in accounts held by, or for the benefit of the Borrower or any Restricted Subsidiary, exceeds $25,000,000 (excluding any outstanding checks and electronic funds transfers) then on each immediately following Business Day the Borrower shall, or shall cause its Restricted Subsidiaries to, transfer funds from such accounts to the Controlled Account in the amount of such excess.

(c) From time to time, if a Borrowing Base Deficiency exists, then notwithstanding other terms provided in this Agreement permitting the Borrower to remedy such deficiency over a period of time or by providing additional Collateral, the Borrower shall immediately apply funds then in the Controlled Account to make a prepayment of the Advances, and if the Advances have been repaid in full, make deposits

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into the Cash Collateral Account to provide cash collateral for the Letter of Credit Exposure, in an aggregate amount equal to the lesser of (i) the funds then in the Controlled Account and (ii) the amount necessary to cure the Borrowing Base Deficiency. Each prepayment pursuant to this Section 6.25(c) shall be accompanied by accrued interest on the amount prepaid to the date of such prepayment and amounts, if any, required to be paid pursuant to Section 2.12 as a result of such prepayment being made on such date. Each prepayment under this Section 6.25(c) shall be applied to the Advances as determined by the Administrative Agent except that, with respect to a specific Borrowing Base Deficiency, if the Borrower elects to cure such Borrowing Base Deficiency with five monthly installments as permitted under Section 2.05(b) then the prepayments under this Section 6.25(c) shall be applied as prepayments of such remaining monthly installments on a pro rata basis. To effectuate the payments and Cash Collateral deposit required under this clause (c), the Borrower hereby authorizes Wells Fargo, as a depository bank, to initiate debit entries to the Controlled Account to debit such required amount from such account. The Borrower represents that the Borrower is and will be the owner of all funds in such Controlled Account. Borrower, for itself and its Subsidiaries, acknowledges that (x) such debit entries may cause an overdraft of such accounts which may result in Wells Fargo’s refusal to honor items drawn on such accounts until adequate deposits are made to such account, (y) Wells Fargo is under no duty or obligation to initiate any debit entry for any purpose, and (z) if a debit is not made the payment may be late or past due.

(k) Section 7.01 (Events of Default) of the Credit Agreement is hereby amended by replacing clause (l), (m) and (o) therein in its entirety with the following clause (l), (m) and (o):

(l) Controlled Account. any of the provisions of the Control Agreement shall, for any reason cease to be valid, binding and enforceable in accordance with its terms or the Controlled Account or any funds therein are subject to any Lien or other rights of a Person other than (i) the Lien in favor of the Administrative Agent and the Second Lien Administrative Agent, (ii) the Liens permitted under Section 6.01(b), (iii) Lien in favor of the depository bank in accordance with the terms of the Control Agreement, and (iv) the rights of the Borrower to the funds held therein subject to the restrictions in Section 6.25 and the terms thereof;

(m) Third Lien Loan Documents. Any “event of default”, however denominated, under any Third Lien Loan Document shall have occurred;

(o) Intercreditor Agreement. Until the Junior Debt Payoff has occurred, unless such Debt was paid in violation of the terms of this Agreement or the Intercreditor Agreement, any of the provisions of the Intercreditor Agreement shall, for any reason cease to be valid and binding or otherwise cease to be in full force and effect and valid, binding and enforceable in accordance with its terms against any Loan Party or any holder of any Second Lien Debt or Third Lien Debt, as applicable, or shall be repudiated in writing by any such Person.

(a) Section 7.06 (Application of Proceeds) of the Credit Agreement is hereby amended by replacing it in its entirety with the following:

Section 7.06 Application of Proceeds. From and during the continuance of any Event of Default, any monies or Property actually received by the Administrative Agent pursuant to this Agreement or any other Loan Document shall be applied as determined

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by the Administrative Agent; provided that, if directed by the Required Lenders, or if the Obligations have been accelerated pursuant to Section 7.02 or Section 7.03, or the Administrative Agent or any Lender has exercised any rights or remedies under this Agreement or any other Loan Document, or any other agreement with the Borrower or any of its Restricted Subsidiaries that secures any of the Obligations, all payments received on account of the Obligations and all net proceeds from the enforcement of the Obligations shall be applied by the Administrative Agent as follows:

First, to payment of that portion of the Obligations constituting fees, indemnities, expenses and other amounts, including attorney fees, payable to the Administrative Agent in its capacity as such and the Issuing Lender in its capacity as such, ratably among the Administrative Agent and the Issuing Lender in proportion to the respective amounts described in this clause First payable to them;

Second, to payment of that portion of the Obligations constituting fees, indemnities and other amounts (other than principal and interest) payable to the Lenders under the Loan Documents, including attorney fees, ratably among the Lenders in proportion to the respective amounts described in this clause Second payable to them;

Third, to payment of that portion of the Obligations constituting accrued and unpaid interest on the Advances and Reimbursement Obligations, ratably among the Lenders in proportion to the respective amounts described in this clause Third payable to them;

Fourth, to payment of that portion of the Obligations constituting unpaid principal of the Advances, Reimbursement Obligations and payment obligations then owing under Hedge Contracts and Banking Services Obligations, ratably among the Lenders, the Issuing Lender, the Swap Counterparties and the holders of the Banking Service Obligations in proportion to the respective amounts described in this clause Fourth payable to them;

Fifth, to the Administrative Agent for the account of the Issuing Lender, to cash collateralize any Letter of Credit Obligations then outstanding;

Sixth, to the Second Lien Agent or the applicable administrative agent or secured party for the Third Lien Debt, if any, as required under the Intercreditor Agreement;

Last, the balance, if any, after all of the Obligations have been indefeasibly paid in full, to the Borrower or as otherwise required by applicable Legal Requirement.

Notwithstanding the foregoing, Banking Services Obligations and Obligations arising under Hedge Contracts shall be excluded from the application described above if the Administrative Agent has not received written notice thereof, together with such supporting documentation as the Administrative Agent may request, from the applicable holder of such Obligation, as the case may be. Each holder of such Obligation not a party to this Agreement that has given the notice contemplated by the preceding sentence shall, by such notice, be deemed to have acknowledged and accepted the appointment of the Administrative Agent pursuant to the terms of Article VIII for itself and its Affiliates as if a “Lender” party hereto.

Notwithstanding anything herein to the contrary, this Section 7.06 may not be amended, waived or otherwise modified in a manner that would alter the pro rata sharing of payments or order of application required hereunder without the written consent of each Lender directly and adversely affected thereby.

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(b) Exhibit B – Compliance Certificate attached to the Credit Agreement is hereby replaced in its entirety with Exhibit B – Compliance Certificate attached hereto.

Section 3. Representations and Warranties. Each of the Guarantors and the Borrower hereby represents and warrants that: (a) after giving effect to this Agreement, the representations and warranties contained in the Credit Agreement, as amended hereby, and the representations and warranties contained in the other Loan Documents are true and correct in all material respects (except that such materiality qualifier shall not be applicable to any representation or warranty that already is qualified or modified by materiality in the text thereof) on and as of the Amendment No. 13 Effective Date as if made on and as of such date except to the extent that any such representation or warranty expressly relates solely to an earlier date, in which case such representation or warranty is true and correct in all material respects (except that such materiality qualifier shall not be applicable to any representation or warranty that already is qualified or modified by materiality in the text thereof) as of such earlier date; (b) no Default has occurred which is continuing; (c) the execution, delivery and performance of this Agreement are within the corporate, limited liability company, or partnership power and authority of such Person and have been duly authorized by appropriate corporate and governing action and proceedings; (d) this Agreement constitutes the legal, valid, and binding obligation of such Person enforceable in accordance with its terms, except as limited by applicable bankruptcy, insolvency, reorganization, moratorium, or similar laws affecting the rights of creditors generally and general principles of equity; (e) there are no governmental or other third party consents, licenses and approvals required in connection with the execution, delivery, performance, validity and enforceability of this Agreement; and (f) the Liens under the Security Instruments are valid and subsisting and secure the Borrower’s and the Guarantors’ obligations under the Loan Documents.

Section 4. Conditions to Effectiveness. This Agreement shall become effective on the Amendment No. 13 Effective Date and enforceable against the parties hereto upon the occurrence of the following conditions precedent:

(a) the Administrative Agent shall have received multiple original counterparts, as requested by the Administrative Agent, of this Agreement, duly and validly executed and delivered by duly authorized officers of the Borrower, the Guarantors and the requisite Lenders;

(b) the Administrative Agent shall have received copy of the Agreement and Amendment No. 1 to the Second Lien Credit Agreement (“Second Lien Amendment”) which, among other things, amends the corresponding provisions therein as those of the Credit Agreement amended pursuant to this Agreement, in form and substance reasonably satisfactory to the Administrative Agent;

(c) the Administrative Agent shall have received copies, certified as of the date of this Agreement by a Responsible Officer of the Borrower of the resolutions of the board of directors of the General Partner, as general partner of the Borrower, approving this Agreement, the Second Lien Amendment and the Control Agreement and the execution and delivery of each such agreement by the Borrower; and

(d) the Borrower shall have paid (i) all reasonable fees and expenses of the Administrative Agent’s outside legal counsel and other consultants pursuant to all invoices presented for payment prior to the Amendment No. 13 Effective Date and (ii) the fees required under Section 5(f) below.

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Section 5. Acknowledgments and Agreements.

(a) The Borrower and each Guarantor acknowledges that on the date hereof all outstanding Obligations are payable in accordance with their terms and the Borrower and each Guarantor hereby waives any defense, offset, counterclaim or recoupment with respect thereto.

(b) The Administrative Agent and the Lenders hereby expressly reserve all of their rights, remedies, and claims under the Loan Documents. Nothing in this Agreement shall constitute a waiver or relinquishment of (i) any Default or Event of Default under any of the Loan Documents, (ii) any of the agreements, terms or conditions contained in any of the Loan Documents, (iii) any rights or remedies of the Administrative Agent or any Lender with respect to the Loan Documents, or (iv) the rights of the Administrative Agent or any Lender to collect the full amounts owing to them under the Loan Documents.

(c) Each of the parties hereto hereby adopt, ratify, and confirm the Credit Agreement, as amended hereby, and acknowledges and agrees that the Credit Agreement, as amended hereby, is and remains in full force and effect, and the Borrower and the Guarantors acknowledge and agree that their respective liabilities and obligations under the Credit Agreement, as amended hereby, the Security Agreement, and the Guaranties, are not impaired in any respect by this Agreement.

(d) From and after the Amendment No. 13 Effective Date, all references to the Credit Agreement and the Loan Documents shall mean such Credit Agreement and such Loan Documents as amended by this Agreement.

(e) This Agreement is a Loan Document for the purposes of the provisions of the other Loan Documents. Without limiting the foregoing, any breach of representations, warranties, and covenants under this Agreement shall be a Default or Event of Default, as applicable, under the Credit Agreement.

(f) The Borrower hereby agrees to pay to the Administrative Agent, for the account of each Lender executing this Agreement and delivering a facsimile, e-mail or original of its signature pages hereto to the Administrative Agent (or its counsel) by 10:00 am, Houston, Texas time on Monday, February 3, 2016 (or such later time as to any Lender as may be agreed by the Borrower in its sole discretion), an amendment fee for each such Lender equal to 0.05% times such Lender’s Pro Rata share of the Borrowing Base in effect on the date hereof. Each such amendment fee as to each such Lender executing this Agreement (i) is payable in U.S. dollars in immediately available funds, (ii) is not refundable under any circumstances, (iii) will not be subject to counterclaim, defense, setoff or otherwise affected, (iv) is deemed fully earned by such Lender once its signature page is delivered as provided above and the Amendment No. 13 Effective Date has occurred, and (v) is due and payable on the Amendment No. 13 Effective Date.

Section 6. Reaffirmation of the Guaranty. Each Guarantor hereby ratifies, confirms, acknowledges and agrees that its obligations under its respective Guaranty are in full force and effect and that such Guarantor continues to unconditionally and irrevocably guarantee the full and punctual payment, when due, whether at stated maturity or earlier by acceleration or otherwise, of all of the Guaranteed Obligations (as defined in the Guaranties), as such Guaranteed Obligations may have been amended by this Agreement, and its execution and delivery of this Agreement does not indicate or establish an approval or consent requirement by such Guarantor under its respective Guaranty in connection with the execution and delivery of amendments, consents or waivers to the Credit Agreement, the Notes or any of the other Loan Documents.

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Section 7. Counterparts. This Agreement may be signed in any number of counterparts, each of which shall be an original and all of which, taken together, constitute a single instrument. This Agreement may be executed by facsimile signature or other similar electronic means and all such signatures shall be effective as originals.

Section 8. Successors and Assigns. This Agreement shall be binding upon and inure to the benefit of the parties hereto and their respective successors and assigns permitted pursuant to the Credit Agreement.

Section 9. Invalidity. In the event that any one or more of the provisions contained in this Agreement shall for any reason be held invalid, illegal or unenforceable in any respect, such invalidity, illegality or unenforceability shall not affect any other provision of this Agreement.

Section 10. Governing Law. This Agreement shall be deemed to be a contract made under and shall be governed by and construed in accordance with the laws of the State of Texas.

Section 11. Entire Agreement. THIS AGREEMENT, THE CREDIT AGREEMENT, AS AMENDED BY THIS AGREEMENT, THE NOTES, AND THE OTHER LOAN DOCUMENTS CONSTITUTE THE ENTIRE UNDERSTANDING AMONG THE PARTIES HERETO WITH RESPECT TO THE SUBJECT MATTER HEREOF AND SUPERSEDE ANY PRIOR AGREEMENTS, WRITTEN OR ORAL, WITH RESPECT THERETO.

THERE ARE NO UNWRITTEN ORAL AGREEMENTS AMONG THE PARTIES.

[The remainder of this page has been left blank intentionally.]

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EXECUTED effective as of the date first above written.

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