Exhibit 10.12

MASTER ASSIGNMENT, AGREEMENT AND AMENDMENT NO. 3
TO CREDIT AGREEMENT

This MASTER ASSIGNMENT, AGREEMENT AND AMENDMENT NO. 3 TO CREDIT AGREEMENT (this “Agreement”) dated as of November 18, 2011 (“Effective Date”) is among Jones Energy Holdings, LLC, a Delaware limited liability company (the “Borrower”), the undersigned subsidiaries of the Borrower as guarantors (the “Guarantors”), the Lenders (as defined below), Wells Fargo Bank, N.A. (“Wells Fargo”), in its capacity as administrative agent for the Lenders (in such capacity, the “Administrative Agent”) and in its individual capacity as a Lender, Union Bank, N.A. (in its individual capacity as a Lender, “UB”), Capital One, National Association (in its individual capacity as a Lender, “Capital One”), Toronto Dominion (New York) LLC (in its individual capacity as a Lender, “TD”), Credit Agricole Corporate and Investment Bank (in its individual capacity as a Lender, “Credit Agricole”), Compass Bank (in its individual capacity as a Lender, “Compass”), Comerica Bank (in its individual capacity as a Lender, “Comerica”, and together with Wells Fargo, UB, Capital One, TD, Credit Agricole, and Compass, the “Existing Lenders”), and JPMorgan Chase Bank, N.A. (the “New Lender”). All the Existing Lenders (other than Comerica) are sometimes herein referred to as “Assignors” and Comerica and the New Lender are sometimes herein referred to as “Assignees”).

RECITALS

A. The Borrower is party to that certain Credit Agreement dated as of December 31, 2009 among the Borrower, the financial institutions party thereto from time to time, as lenders (the “Lenders”) and the Administrative Agent, as heretofore amended, including by that certain Agreement and Amendment No. 1 dated as of September 15, 2010 (“Amendment No. 1”) and that by certain Master Assignment, Agreement and Amendment No. 2 dated as of April 14, 2011 (“Amendment No. 2”; and such Credit Agreement, as heretofore amended, the “Credit Agreement”).

B. The Borrower has requested that the Lenders (i) agree to increase the Borrowing Base under the Credit Agreement, (ii) consent to an increase in the Second Lien Notes, (iii) agree to increase their Maximum Credit Amounts and (iv) waive the prior written notice required under Section 3.04(b) of the Credit Agreement with regard to the Borrower’s prepayment of Borrowings in the amount of $30,000,000 in connection with the increase in the Second Lien Notes.

C. To provide for part of the increase in the Borrowing Base, the New Lender has agreed to become party to the Credit Agreement pursuant to the terms hereof, and the Assignors wish to assign certain percentages of their rights and obligations under the Credit Agreement as Lenders to the Assignees pursuant to the terms hereof.

D. After the assignment and assumption of the rights and obligations as set forth herein have been made effective, the parties hereto wish to, subject to the terms and conditions of this Agreement, (i) increase the Borrowing Base and (ii) amend the Credit Agreement as provided 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:

Section 1. Defined Terms. 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. Unless otherwise specifically defined herein, each term defined in the Credit Agreement and used herein without definition shall have the meaning assigned to such term in the Credit Agreement.

Section 2. Other Definitional Provisions. 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 3. Master Assignment.

(a) Assignments. For an agreed consideration, each Assignor hereby irrevocably and severally sells and assigns to the Assignees, without recourse and without representation or warranty other than as expressly provided herein, and the Assignees hereby irrevocably and severally purchase and assume from each Assignor, subject to the terms hereof and of the Credit Agreement, (i) such percentage in and to all of such Assignor’s respective rights and obligations in its capacity as a Lender under the Credit Agreement (including, without limitation, such percentage interest in the Advances owing to such Assignor and such Assignor’s risk participation and funded participation in Letter of Credit Obligations existing as of the date hereof (prior to the effectiveness of this Agreement)) that would result in the Assignors and the Assignees having the respective Maximum Credit Amounts set forth on Schedule A attached hereto, and (ii) to the extent permitted to be assigned under applicable law, all claims, suits, causes of action and any other right of such Assignor (in its capacity as a Lender) against any Person, whether known or unknown, arising under or in connection with the Credit Agreement, any other Loan Document or the loan transactions governed thereby or in any way based on or related to any of the foregoing, including, but not limited to, contract claims, tort claims, malpractice claims, statutory claims and all other claims at law or in equity related to the rights and obligations sold and assigned pursuant to clause (i) above. Each such sale and assignment is without recourse to any Assignor and, except as expressly provided in this Agreement, without representation or warranty by any Assignor. After giving effect to the sales and assignments pursuant to this Section 3, the increase in the Borrowing Base set forth in Section 4 below and the increase in the Maximum Credit Amounts effected under Section 6 below, each Lender’s (including the Assignees’) Maximum Credit Amount will be as set forth next to its name on Annex I attached hereto.

(b) Representations and Warranties of Assignors. Each Assignor (i) represents and warrants that (A) it is the legal and beneficial owner of the interests that it is assigning under clause (a) above, (B) such interests are free and clear of any lien, encumbrance or other adverse claim and (C) it has full power and authority, and has taken all action necessary, to execute and deliver this Agreement and to consummate the transactions contemplated hereby; and (ii) assumes no responsibility with respect to (A) any statements, warranties or representations made in or in connection with the Credit Agreement or any other Loan Document, (B) the execution, legality, validity, enforceability, genuineness, sufficiency or value of the Loan Documents or any collateral thereunder, (C) the financial condition of the Borrower, its Subsidiaries or Affiliates or any other Person obligated in respect of any Loan Document or (D) the performance or observance by the Borrower, its Subsidiaries or Affiliates or any other Person of any of its obligations under any Loan Document.

(c) Representations and Warranties of Assignee. Each Assignee (i) represents and warrants that (A) it has full power and authority, and has taken all action necessary, to execute and deliver this Agreement and to consummate the transactions contemplated hereby and to become a Lender under the Credit Agreement, (B) it meets all the requirements to be an assignee under Section 12.04 of the Credit Agreement (subject to such consents, if any, as may be required under Section 12.04 of the Credit Agreement), (C) from and after the Effective Date, it shall be bound by the provisions of the Credit

Agreement as a Lender thereunder and, to the extent of the interests assigned to it hereunder, shall have the obligations of a Lender thereunder, (D) it is sophisticated with respect to decisions to acquire assets of the type represented by the interests assigned to it hereunder and either it, or the person exercising discretion in making its decision to acquire the interests assigned to it hereunder, is experienced in acquiring assets of such type, (E) it has received a copy of the Credit Agreement, and has received or has been accorded the opportunity to receive copies of the most recent financial statements delivered pursuant to Section 8.01 thereof, as applicable, and such other documents and information as it deems appropriate to make its own credit analysis and decision to enter into this Agreement and to purchase the interests assigned to it hereunder, and (F) it has, independently and without reliance upon the Administrative Agent or any Assignor and based on such documents and information as it has deemed appropriate, made its own credit analysis and decision to enter into this Agreement and to purchase the interests assigned to it hereunder; and (ii) agrees that (A) it will, independently and without reliance on the Administrative Agent or any Assignor or any other Assignee, and based on such documents and information as it shall deem appropriate at the time, continue to make its own credit decisions in taking or not taking action under the Loan Documents, and (B) it will perform in accordance with their terms all of the obligations which by the terms of the Loan Documents are required to be performed by it as a Lender.

(d) Payments. From and after the Effective Date, the Administrative Agent shall make all payments in respect of the interests assigned hereunder (including payments of principal, interest, fees and other amounts) to the relevant Assignors for amounts which have accrued to but excluding the Effective Date and to the relevant Assignees for amounts which have accrued from and after the Effective Date. To the extent necessary, the Assignors and the Assignees shall make all appropriate adjustments in payments by the Administrative Agent for periods prior to the Effective Date or with respect to the making of the assignments contemplated hereby directly between themselves.

(e) Consents. The Borrower, the Administrative Agent and the Issuing Bank hereby consent to the assignments made under this Section 3 to the New Lender.

Section 4. Increase in the Borrowing Base. Subject to the terms of this Agreement, as of the Effective Date, the Borrowing Base shall be increased to $400,000,000 and such Borrowing Base shall remain in effect at that level until the effective date of the next Borrowing Base redetermination made in accordance with the terms of the Credit Agreement, as amended hereby. The parties hereto acknowledge and agree that the Borrowing Base redetermination set forth in this Section 4 shall be and be deemed to be the Scheduled Redetermination scheduled for November 1, 2011 as provided in Section 2.07(b) of the Credit Agreement. Each Existing Lender’s and the New Lender’s Applicable Percentage of the resulting Borrowing Base, after giving effect to the assignments made pursuant to Section 3 above and the increase in the Borrowing Base set forth in this Section 4, is set forth in Annex II attached hereto.

Section 5. Consent to Second Lien Increase; Consent to Intercreditor Amendment.

(a) Under Section 7.01(b) of the Intercreditor Agreement, the Second Lien Term Loan Documents may not be amended to, among other things, result in the aggregate principal amount of Debt issued thereunder exceeding $40,000,000. Pursuant to Amendment No. 1, the Lenders consented to the increase in the aggregate principal amount of Debt issued under the Second Lien Term Loan Agreement from $40,000,000 to $55,000,000. Furthermore, pursuant to Amendment No. 2, the Lenders consented to the increase in the aggregate principal amount of Debt issued under the Second Lien Term Loan Agreement from $55,000,000 to $90,000,000. The Lenders hereby consent to (a) the further increase in the aggregate principal amount of Debt issued under the Second Lien Term Loan Agreement from $90,000,000 to $120,000,000 (the “Second Lien Increase”), provided that, the Second Lien Increase shall be effected pursuant to the terms of the Second Lien Amendment in substantially the same form as attached hereto as Exhibit A, and (b) the payment by the Borrower of fees (which may be paid in the form

of original issue discount) in connection with the Second Lien Increase which are acceptable to the Arranger. The consents by the Lenders described in this Section 5(a) are limited to the Second Lien Increase as described herein.

(b) Each party hereto hereby (i) acknowledges that it has received a copy of the Intercreditor Amendment (as defined Section 9 below), and (ii) consents to the amendments to the Intercreditor Agreement to be effected thereby. Each Lender (including the New Lender) authorizes the Administrative Agent to execute and deliver the Intercreditor Amendment.

Section 6. Amendment to Credit Agreement. For the purpose of increasing the aggregate Maximum Credit Amounts and to include the New Lender’s Maximum Credit Amount, the Credit Agreement is hereby further amended by deleting Annex I (List of Maximum Credit Amounts) attached thereto and replacing it with the Annex I (List of Maximum Credit Amounts) attached hereto.

Section 7. Limited Waiver. Under Section 3.04(b) of the Credit Agreement, the Borrower is required to notify the Administrative Agent in advance of any prepayment of Borrowings under the Credit Agreement. The Lenders hereby waive the required notice with regard to the Borrower’s prepayment of Borrowings in the amount of $30,000,000, to be made with the proceeds of the Second Lien Increase on the date of such Second Lien Increase. The waiver by the Lenders described in this Section 7 is limited to the required notice of prepayment described herein and shall not be construed to be a consent to or a permanent waiver of Section 3.04(b) of the Credit Agreement (other than as to the required notice as set forth above) or any other terms, provisions, covenants, warranties or agreements contained in the Credit Agreement or any other Loan Document.

Section 8. Credit Parties Representations and Warranties. Each Credit Party 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 Effective Date as if made on as 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) after giving effect to this Agreement, no Default has occurred and is continuing; (c) the execution, delivery and performance of this Agreement are within the limited liability company, limited partnership, or corporate power and authority of such Credit Party and have been duly authorized by appropriate limited liability company, limited partnership or corporate action and proceedings; (d) this Agreement constitutes the legal, valid, and binding obligation of such Credit Party 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; (f) the Liens under the Security Instruments are valid and subsisting and secure the Indebtedness (as such Indebtedness may be increased as a result of the transactions contemplated hereby); and (g) no authorization or approval or other action by, and no notice to or filing with, any Governmental Authority or other Person (other than those that have been, or on the Effective Date will be, duly obtained or made and that are, or on the Effective Date will be, in full force and effect) is required for the incurrence of the Second Lien Increase or for the due execution, delivery and/or performance of Second Lien Loan Documents in connection with the Second Lien Increase, in each case by the parties thereto.

Section 9. Conditions to Effectiveness. This Agreement shall become effective on the Effective Date and enforceable against the parties hereto upon the occurrence of the following conditions precedent:

(a) The Administrative Agent shall have received:

(i) 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, the Administrative Agent, the Existing Lenders and the New Lender;

(ii) a copy of the fully executed Agreement and Amendment No. 3 to Second Lien Term Loan Agreement (“Second Lien Amendment”) which provides for the Second Lien Increase and the incurrence thereof, in substantially the same form as attached hereto as Exhibit A;

(iii) a copy of the fully executed Amendment No. 1 to Intercreditor Agreement (“Intercreditor Amendment”) in substantially the same form as attached hereto as Exhibit B;

(iv) executed original Notes, if any, requested by the Lenders made by the Borrower payable to such requesting Lenders in the amount of such Lenders’ respective Maximum Credit Amounts after giving effect to the transactions contemplated hereby;

(v) executed and notarized new Mortgages, and/or amendments or supplements to existing Mortgages, covering additional Oil and Gas Properties of the Borrower and its Subsidiaries, in form and substance reasonably satisfactory to the Administrative Agent, to the extent necessary to (A) cause the Administrative Agent to have a first priority, perfected Lien (subject only to Liens permitted under Section 9.03 of the Credit Agreement) on at least 80% of the Engineered Value of the Oil and Gas Properties evaluated in the Reserve Reports most recently delivered to the Administrative Agent, and (B) increase any maximum amounts referenced in any existing Mortgages to account for the increase in the aggregate Maximum Credit Amounts effected hereby;

(vi) a certificate, dated as of the Effective Date, duly executed and delivered by the Borrower’s and each Guarantor’s Secretary or Assistant Secretary as to (A) no change in the officers’ incumbency delivered at the original closing date for the Credit Agreement, (B) no change in authorizing resolutions delivered at such closing date and (C) no change in organizational documents delivered at such closing date or, if any such changes have occurred, attaching new incumbency certificates, authorizing resolutions and/or organizational documents, as they case may be;

(vii) certificates of existence and good standing for the Borrower in its state of organization, which certificates shall be dated a date not sooner than 30 days prior to Effective Date; and

(viii) such other information, documents, governmental certificates, agreements, and lien searches as the Administrative Agent or any Existing Lender or the New Lender may reasonably request.

(b) The Administrative Agent shall have received evidence satisfactory to it that conditions precedent and all other actions necessary for the Second Lien Increase to be funded under the Second

Lien Credit Agreement, as amended by the Second Lien Amendment, have been met or have occurred (other than the consents and agreements provided under this Agreement).

(c) The Administrative Agent shall have received such title information as the Administrative Agent may reasonably require setting forth the status of title to at least 80% of the Engineered Value of the Oil and Gas Properties evaluated in the Reserve Reports most recently delivered to the Administrative Agent.

(d) The representations and warranties in this Agreement shall be true and correct in all material respects.

(e) The New Lender shall have received all documentation and other information that is required by regulatory authorities under applicable “know your customer” and anti-money-laundering rules and regulations, including, without limitation, the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)).

(f) The Borrower shall have paid all fees required to be paid on the closing of this Agreement as separately agreed among the Borrower, the Arranger, the Administrative Agent and the Second Lien Administrative Agent.

Section 10. Acknowledgments and Agreements.

(a) The Borrower acknowledges that on the date hereof all outstanding Indebtedness is payable in accordance with its terms and the Borrower waives any defense, offset, counterclaim or recoupment with respect thereto.

(b) The Administrative Agent, the Issuing Bank, and the Lenders hereby expressly reserve all of their rights, remedies, and claims under the Loan Documents, as amended hereby. Except as expressly set forth herein, this Agreement shall not constitute a waiver or relinquishment of (i) any Default or Event of Default under any of the Loan Documents, as amended hereby, (ii) any of the agreements, terms or conditions contained in any of the Loan Documents, as amended hereby, (iii) any rights or remedies of the Administrative Agent, the Issuing Bank, or any Lender with respect to the Loan Documents, as amended hereby, or (iv) the rights of the Administrative Agent, the Issuing Bank, or any Lender to collect the full amounts owing to them under the Loan Documents, as amended hereby.

(c) The Borrower, each Guarantor, the Administrative Agent, the Issuing Bank and each Lender do hereby adopt, ratify, and confirm the Credit Agreement, as amended hereby, and acknowledge and agree that the Credit Agreement, as amended hereby, is and remains in full force and effect, and the Borrower and each Guarantor acknowledge and agree that their respective liabilities and obligations under the Credit Agreement, as amended hereby, the Guarantee and Collateral Agreement and the other Loan Documents are not impaired in any respect by this Agreement.

(d) From and after the Effective Date, all references to the Credit Agreement in the Loan Documents shall mean the Credit Agreement, as amended by this Agreement. This Agreement is a Loan Document for the purposes of the provisions of the other Loan Documents.

Section 11. Reaffirmation of the Guaranty. Each Guarantor hereby ratifies, confirms, acknowledges and agrees that its obligations under the Guarantee and Collateral Agreement 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 Obligations (as defined in the Guarantee and Collateral Agreement), as such 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 the Guarantee and Collateral Agreement 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.

Section 12. 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 or PDF electronic mail signature, and all such signatures shall be effective as originals.

Section 13. 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 14. 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 15. 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 16. 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.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be executed by their respective officers thereunto duly authorized as of the day and year first above written.

BORROWER:	JONES ENERGY HOLDINGS, LLC


	By:
	Name:	Craig Fleming
	Title:	Senior Vice President and Chief Financial Officer


GUARANTORS:	JELGP, LLC
	J/M CRUSADER ACQUISITION SUB LLC
	NOSLEY PROPERTIES, LLC
	CRUSADER HOLDINGS, LLC
	CRUSADER ENERGY GROUP, LLC
	CRUSADER MANAGEMENT, LLC
	HAWK ENERGY FUND I, LLC
	KNIGHT ENERGY GROUP, LLC
	KNIGHT ENERGY GROUP II, LLC
	KNIGHT ENERGY MANAGEMENT, LLC
	RCH UPLAND ACQUISITION, LLC


	Each by:
	Name:			Craig Fleming
	Title:			Senior Vice President and Chief Financial Officer

	JONES ENERGY, LTD.

	By: JELGP, LLC, its general partner


			By:
			Name:		Craig Fleming
			Title:		Senior Vice President and Chief Financial Officer

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