Exhibit 99.1

EXECUTION COPY

AMENDED AND RESTATED RESTRUCTURING SUPPORT AGREEMENT

AMENDED AND RESTATED RESTRUCTURING SUPPORT AGREEMENT (this “Agreement”), dated as of December 26, 2011, among (i) Dynegy Inc. (“DI”), (ii) Dynegy Holdings, LLC (“DH”), on behalf of itself and certain of its subsidiaries (collectively, the “Company”)(1) and (iii) the undersigned, each as the beneficial owners (or advisors, nominees or investment managers for the beneficial owner(s)) of a portion of the outstanding Notes (as defined herein) issued by DH (the “Consenting Noteholders” and, together with DI and the Company, each referred to as a “Party” and collectively referred to as the “Parties”).

WHEREAS, prior to the date hereof, DH, DI and the Consenting Noteholders have discussed the possibility of consummating a financial restructuring of the Company’s indebtedness and other obligations as set forth in this Agreement and the accompanying Restructuring Term Sheet (as defined herein) (the “Restructuring”).

WHEREAS, it is anticipated that the Restructuring will be implemented through a solicitation of votes for a chapter 11 plan of reorganization of the Company, pursuant to sections 1125, 1126 and 1145 of the Bankruptcy Code, which chapter 11 plan shall contain in all material respects the same terms and conditions set forth in the Restructuring Term Sheet.

WHEREAS, on November 7, 2011 (the “Petition Date”), DH and certain of its subsidiaries each filed voluntary petitions for relief under chapter 11 of title 11 of the United States Code (the “Bankruptcy Code”) in the United States Bankruptcy Court for the Southern District of New York, Poughkeepsie Division (the “Bankruptcy Court”), and each thereby commenced chapter 11 bankruptcy cases that are jointly administered under Case No. 11-38111 (CGM) (the “Chapter 11 Cases”).

WHEREAS, this Agreement and the Restructuring Term Sheet, which is incorporated herein by reference and is made part of this Agreement, set forth the agreement among the Parties concerning their commitment, subject to the terms and conditions hereof and thereof, to implement the Restructuring.  In the event the terms and conditions as set forth in the Restructuring Term Sheet and this Agreement are inconsistent, the terms and conditions in the Restructuring Term Sheet shall govern.

WHEREAS, the Parties entered into a Restructuring Support Agreement dated as of November 7, 2011 (as amended pursuant to the First Amendment to the Restructuring Support Agreement, dated as of December 9, 2011 and the Second Amendment to the Restructuring Support Agreement, dated as of December 16, 2011, the “Original Agreement”).

WHEREAS, the Parties wish to amend and restate the Original Agreement in its entirety as set forth below.

NOW, THEREFORE, in consideration of the promises and mutual covenants and agreements set forth herein, and for other good and valuable consideration, the receipt and

(1)           Specifically, the term “Company” as used in this Agreement consists of the following entities, each of which would be a debtor under Chapter 11 of the Bankruptcy Code) on the terms and conditions contemplated in this Agreement:  Dynegy Holdings, LLC, Dynegy Northeast Generation, Inc., Hudson Power, L.L.C., Dynegy Danskammer, L.L.C. and Dynegy Roseton, L.L.C.

sufficiency of which are hereby acknowledged, each Party, intending to be legally bound, hereby agrees as follows:

1.             Definitions.  The following terms shall have the following definitions:

“Ad Hoc Bondholder Committee” means the Consenting Noteholders that are members of an ad hoc bondholder committee represented by Paul, Weiss, Rifkind, Wharton & Garrison LLP and Houlihan Lokey Capital, Inc.

“Agreement” has the meaning set forth in the preamble hereto.

“Alternative Plan” has the meaning set forth in Section 3(c) hereto.

“Ballot” means the ballot distributed with the Disclosure Statement for voting on the Plan.

“Bankruptcy Code” has the meaning set forth in the preamble hereto.

“Bankruptcy Court” has the meaning set forth in the preamble hereto.

 “Business Day” means any day other than Saturday, Sunday and any day that is a legal holiday or a day on which banking institutions in New York, New York are authorized by law or governmental action to close.

“Certificate of Designation” means that certain Certificate of Designation of Dynegy Inc., pursuant to Section 151 of the General Corporate Law of the State of Delaware, to be dated as of the Effective Date, governing the Series A Redeemable Convertible Preferred Stock, which shall be consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

“Chapter 11 Cases” has the meaning set forth in the preamble hereto.

“Confirmation Order” means the order entered by the Bankruptcy Court confirming the Plan, including all exhibits, appendices and related documents, each consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

“Consenting Noteholders” has the meaning set forth in the preamble hereto.

“Disclosure Certificate” means a certificate substantially in the form of Exhibit B to this Agreement.

“Disclosure Statement” means the disclosure statement in respect of the Plan which shall be consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

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“Disclosure Statement Order” means the order entered by the Bankruptcy Court approving the solicitation of votes on the Plan, which shall be consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

“Effective Date” means the date on which all conditions to consummation of the Plan have been satisfied (or waived) and the Plan becomes effective.

“Engagement Letter” means that certain engagement letter, dated as of   October 7, 2011, by and between Paul, Weiss, Rifkind, Wharton & Garrison LLP and DI.

“Majority of the Consenting Noteholders” means the Consenting Noteholders (i) holding a majority of the aggregate principal amount of the Notes held by all Consenting Noteholders listed on Schedule 1 hereto (as of the date of any applicable action or consent) and (ii) constituting not less than two of the Consenting Noteholders listed on Schedule I hereto.

“New Secured Notes Indenture” shall mean that certain Indenture, to be dated as of the Effective Date, governing DI’s 11% New Secured Notes due 2018, which shall be consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

“Noteholder Claims” means all claims arising under or relating to the Notes, the Senior Notes Indenture and/or the Subordinated Notes Indenture and all agreements and instruments relating to the foregoing that remain unpaid and outstanding as of the Effective Date.

“Notes” means the Senior Notes and the Subordinated Notes.

“Parties” and “Party” have the meanings set forth in the preamble hereto.

“Person” means an individual, a partnership, a joint venture, a limited liability company, a corporation, a trust, an unincorporated organization, a group or any legal entity or association.

“Petition Date” has the meaning set forth in the preamble hereto.

 “Plan” means the chapter 11 plan of reorganization of the Company implementing the Restructuring and the Restructuring Term Sheet, which shall be consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders

“Plan Related Documents” means the Plan, the Disclosure Statement, the Solicitation Materials, the Confirmation Order, the New Secured Notes Indenture (and the related security documents) and the Certificate of Designation, and any other documents or agreements, whether or not filed with the Bankruptcy Court by the Company or at the direction of DI or the Company, that are necessary to implement the

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Plan and the Restructuring Term Sheet, including any management incentive plans and any appendices, amendments, modifications, supplements, exhibits and schedules relating to the Plan or Disclosure Statement; provided that each of the foregoing documents shall be consistent in all material respects with the Restructuring Term Sheet and otherwise in form and substance reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

“Restructuring Term Sheet” means that certain term sheet containing the material terms and provisions of the Restructuring agreed upon by the Parties hereto that are to be incorporated into the Plan and Plan Related Documents, a copy of which is attached hereto as Exhibit A.

“Senior Notes” means the 8.750% Senior Notes due 2012, the 7.50% Senior Unsecured Notes due 2015, the 8.375% Senior Unsecured Notes due 2016, the 7.125% Senior Debentures due 2018, the 7.75% Senior Unsecured Notes due 2019, and the 7.625% Senior Debentures due 2026, in each case issued by DH under the Senior Notes Indenture.

“Senior Notes Indenture” means that certain Indenture, dated as of September 26, 1996, restated as of March 23, 1998, and amended and restated as of March 14, 2001, between DH (f/k/a Dynegy Holdings Inc.) and Bank One Trust Company, National Association, as Trustee (as amended, restated and supplemented through the Petition Date).

“Solicitation Materials” means the Disclosure Statement and other solicitation materials in respect of the Plan as approved by the Bankruptcy Court pursuant to Section 1125(b) of the Bankruptcy Code.

“Subordinated Notes” means those certain Series B 8.316% Subordinated Capital Income Securities due 2027 in the initial aggregate principal amount of $200,000,000 issued by DH under the Subordinated Notes Indenture.

“Subordinated Notes Indenture” means that certain Subordinated Debenture Indenture between DH (f/k/a NGC Corporation) and First National Bank of Chicago, as Debenture Trustee, dated as of May 28, 1997 (as amended, restated and supplemented from time to time).

“Transfer” has the meaning set forth in Section 7 hereto.

“Termination Date” has the meaning set forth in Section 5 hereto.

“Termination Event” has the meaning set forth in Section 5 hereto.

2.             Consenting Noteholders’ Consent.  For purposes of this Agreement, unless otherwise specified, where this Agreement provides for the action, consent or approval of the Consenting Noteholders, collectively, such action, consent, or approval shall be upon the agreement of a Majority of the Consenting Noteholders.

3.             Commitment of Consenting Noteholders.  Subject to the terms and conditions of this Agreement and the terms and conditions set forth in the Restructuring Term Sheet, each

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Consenting Noteholder (severally and not jointly), on its behalf and on behalf of its controlled affiliates, agrees that:

(a)           so long as its vote has been properly solicited pursuant to sections 1125 and 1126 of the Bankruptcy Code, each Consenting Noteholder shall vote all Noteholder Claims, now or hereafter beneficially owned by such Consenting Noteholder or for which it now or hereafter serves as the nominee, investment manager or advisor for beneficial holders thereof, in favor of the Plan in accordance with the applicable procedures set forth in the Solicitation Materials, and timely return a duly executed Ballot in connection therewith;

(b)           it shall not withdraw or revoke its tender, consent or vote with respect to the Plan, except as otherwise expressly permitted pursuant to the Agreement; and

(c)           following the commencement of the Chapter 11 Cases, it shall not (i) object to the Plan, Disclosure Statement or the consummation of the Restructuring Term Sheet or Plan, or any efforts to obtain acceptance of, and to confirm and implement, the Plan; (ii) initiate any legal proceedings that are inconsistent with or that would delay, prevent, frustrate or impede the approval, confirmation or consummation of the Restructuring, the Disclosure Statement or the Plan or the transactions outlined therein or in the Restructuring Term Sheet or otherwise commence any proceedings to oppose any of the Plan Related Documents, or take any other action that is barred by this Agreement; (iii) vote for, consent to, support or participate in the formulation of any other restructuring or settlement of the Company’s claims, any other transaction involving the Company or DI, any of their assets, any of their stock, or any plan of reorganization (with the sole exception of the Plan) or liquidation under applicable bankruptcy or insolvency laws, whether domestic or foreign, in respect of the Company; (iv) directly or indirectly seek, solicit, support, formulate, entertain, encourage or engage in discussions, or enter into any agreements relating to, any restructuring, plan of reorganization, proposal or offer of dissolution, winding up, liquidation, reorganization, merger, transaction, sale, disposition or restructuring of the Company (or any of its assets or stock) other than the Plan or as otherwise set forth in the Restructuring Term Sheet (collectively, (iii) and (iv), an “Alternative Plan”); (v) engage in or otherwise participate in any negotiations regarding any Alternative Plan, enter into any letter of intent, memorandum of understanding, agreement in principle or other agreement relating to any Alternative Plan; (vi) solicit, encourage, or direct any Person, including, without limitation the indenture trustee of the Senior Notes Indenture and the indenture trustee of the Subordinated Notes Indenture, to undertake any action set forth in clauses (i) through (v) of this subsection (c); or (vii) permit any of its, or its controlled affiliates’, officers, directors, managers, employees, partners, representatives and agents to undertake any action set forth in clauses (i) through (vi) of this subsection (c).

Notwithstanding the foregoing, nothing in this Agreement shall be construed to prohibit any Consenting Noteholder or DI from appearing as a party-in-interest in any matter to be adjudicated in the Chapter 11 Cases so long as such appearance and the positions advocated in connection therewith are consistent with this Agreement and otherwise in furtherance of the

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Restructuring and are not for the purpose of, and could not reasonably be expected to have the effect of, hindering, delaying or preventing the consummation of the Restructuring.

4.             Commitment of the Company and DI.  Subject to DH’s fiduciary duties as debtor in possession and subject to DI’s fiduciary duties under applicable law, the Company and DI each agrees to use its reasonable best efforts to (i) support and complete the Restructuring and all transactions contemplated under the Restructuring Term Sheet, the Plan and all other Plan Related Documents; (ii) take any and all necessary and appropriate actions in furtherance of the Restructuring and the transactions contemplated under the Restructuring Term Sheet, the Plan and all other Plan Related Documents; (iii) complete the Restructuring and all transactions contemplated under the Restructuring Term Sheet, the Plan and all other Plan Related Documents within the time-frame outlined in this Agreement, including, without limitation, taking all steps necessary and desirable to obtain the Confirmation Order on or before June 15, 2012 and achieve the Effective Date on or prior to August 1, 2012; (iv) obtain any and all required governmental, regulatory and/or third-party approvals for the Restructuring; and (v) take no actions inconsistent with this Agreement, the Restructuring Term Sheet, or the confirmation and consummation of the Plan.

5.             Termination.  This Agreement may be terminated by the mutual consent of the Company, DI and a Majority of the Consenting Noteholders and by any of (i) the Company, (ii) DI or (iii) a Majority of the Consenting Noteholders, upon the occurrence of any of the following events (each a “Termination Event”); provided, however that neither the Company nor DI may terminate this Agreement upon the occurrence of a Termination Event pursuant to clause (i)(I) below and the Consenting Noteholders may not terminate this Agreement upon the occurrence of a Termination Event pursuant to clause (i)(II) below:

(a)           a Termination Event shall have occurred under Section 6 of this Agreement;

(b)           at any time after December 26, 2011, any amendment, restatement, supplement or other modification is made to any Plan Related Document that is inconsistent in any material respect with the Restructuring Term Sheet and the Plan Related Documents approved by each Consenting Noteholder as of December 26, 2011, without the prior consent of the Company, DI and a Majority of the Consenting Noteholders;

(c)           the occurrence of any event, fact or circumstance which has had or would reasonably be expected to have (individually or in the aggregate) (i) a material adverse effect on the business, assets, financial condition, liabilities or results of operations of DI or the Company taken as a whole; or (ii) is or would reasonably be expect to impair in any material respect the ability of DI or the Company to consummate the transactions contemplated by, or to perform its obligations under, this Agreement or the Restructuring Term Sheet;

(d)           the Bankruptcy Court shall have failed to enter the Disclosure Statement Order by March 15, 2012;

(e)           the Bankruptcy Court shall have failed to enter the Confirmation Order by June 15, 2012;

(f)            the Effective Date has not occurred by August 1, 2012;

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(g)           the appointment of a trustee, receiver, examiner with expanded powers, responsible person or responsible officer in the Chapter 11 Cases;

(h)           any court of competent jurisdiction or other competent governmental or regulatory authority shall have issued an order making illegal or otherwise restricting, preventing or prohibiting the Restructuring in a manner that cannot reasonably be remedied by DI, the Company or the Consenting Noteholders;

(i)            the occurrence of a material breach of this Agreement by any of the Parties of any of its obligations under this Agreement, and any such breach is either unable to be cured or is not cured by five (5) days after receipt of written notice (I) from a Majority of the Consenting Noteholders, in the case of a breach by the Company or DI, or (II) from DH or DI, in the case of a breach by a Consenting Noteholder; or

(j)            the termination of the Engagement Letter by the Company or DI.

The date on which this Agreement is terminated in accordance with the provisions of this Section 5 shall be referred to as the “Termination Date” and the provisions of this Agreement and the Restructuring Term Sheet shall terminate, except as otherwise provided in this Agreement, unless, in the case of this Section 5, within five (5) Business Days each of DI, DH and a Majority of the Consenting Noteholders waive, in writing, the occurrence of or amend or modify any of the events set forth in clauses (a) through (h) of this Section 5.  In the event of the termination of this Agreement pursuant to this Section 5, written notice thereof shall forthwith be given to the other party specifying the provision hereof pursuant to which such termination is made, and this Agreement shall be terminated and become void and have no effect and there shall be no liability hereunder on the part of any Party, except that Sections 11, 12, 19-27, and 29 shall survive any termination of this Agreement. Nothing in this Section 5 shall relieve any Party of liability for any breach of this Agreement.

6.             Withdrawal Rights of Individual Consenting Noteholders.  In addition to the Termination Events set forth in Section 5, in the event that (i) any examiner concludes or finds that any member of the Company’s board of directors was more likely than not (or words of similar import or meaning) to have committed acts of fraud, willful misconduct, breach of fiduciary duty or any other acts which would likely make them unable to satisfy the standard set forth in section 1129(a)(5)(A)(ii) of the Bankruptcy Code, (ii) the Bankruptcy Court shall have failed to enter the Disclosure Statement Order by March 15, 2012 or (iii) any amendment, supplement or other modification is made to any Plan Related Document that is inconsistent in any material respect with the Plan Related Documents approved by each Consenting Noteholder as of December 26, 2011, any Consenting Noteholder may, in its individual capacity, terminate its obligations under this Agreement upon two (2) Business Days’ prior notice to DI, the Company and the other Consenting Noteholders; provided further, however, that any termination by a Consenting Noteholder of its obligations under this Agreement pursuant to this Section 6 shall not constitute a Termination Event or affect the obligations or any other Consenting Noteholder under this Agreement, unless a Majority of the Consenting Noteholders terminates its obligations under this Agreement, in which case, a Termination Event and the Termination Date under Section 5 shall be deemed to have immediately occurred without any further notice to DI or the Company.

7.             Transfer of Noteholder Claims.  Notwithstanding anything to the contrary in this Agreement, each of the Consenting Noteholders agrees that (A) unless and until any individual Consenting Noteholder terminates its obligations under this Agreement pursuant to Section 6,

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and (B) thereafter, solely with respect to those Consenting Noteholders who have not previously terminated their obligations under this Agreement pursuant to Section 6, and only for so long as this Agreement has not been terminated in accordance with its terms pursuant to Section 5, it shall not sell, assign, transfer, convey, pledge, hypothecate or otherwise dispose of, directly or indirectly (each such transfer, a “Transfer”), all or any of its Noteholder Claims (or any right related thereto and including any voting rights associated with such Noteholder Claims) unless the transferee thereof (a) agrees in an enforceable writing to assume and be bound by this Agreement and the Restructuring Term Sheet, and to assume the rights and obligations of the Consenting Noteholder under this Agreement and (b) promptly delivers such writing to the Company (each such transferee becoming, upon the Transfer, a Consenting Noteholder hereunder).  The Company shall promptly acknowledge any such Transfer in writing and provide a copy of that acknowledgement to the transferor.  By its acknowledgement of the relevant Transfer, the Company shall be deemed to have acknowledged that its obligations to the Consenting Noteholder hereunder shall be deemed to constitute obligations in favor of the relevant transferee.  Any Transfer of any Noteholder Claim by a Consenting Noteholder that does not comply with the procedure set forth in the first sentence of this Section 7 shall be deemed void ab initio.  This Agreement shall in no way be construed to preclude the Consenting Noteholders from acquiring additional Noteholder Claims, provided that any such additional Noteholder Claims shall automatically be deemed to be subject to the terms of this Agreement, and provided further that the Consenting Noteholders agree to furnish to the Company, DI and advisors to the Ad Hoc Bondholder Committee prompt notice within five (5) Business Days of the acquisition of any additional Notes.

8.             Effectiveness.  This Agreement shall become effective and binding upon each of the undersigned persons as of the date when (i) the Parties have executed and delivered signed copies of this Agreement and (ii) holders (or advisors, nominees, or investment managers for beneficial holder(s)) which represent no less than $1.8 billion in the aggregate of the outstanding Notes have executed this Agreement.  This Agreement is not and shall not be deemed to be a solicitation of votes for the acceptance of the Plan (or any other plan of reorganization) for the purposes of sections 1125 and 1126 of the Bankruptcy Code or otherwise.

9.             Ownership of Claims.  Each of the Consenting Noteholder represents and warrants (severally and not jointly) that:

(a)                                  as of the date of this Agreement, it is the beneficial owner of the principal amount of the Noteholder Claims, or is the nominee, investment manager or advisor for beneficial holders of the Noteholder Claims, as such Consenting Noteholder has disclosed to the Company and advisors to the Ad Hoc Bondholder Committee in a Disclosure Certificate which shall be provided to the Company and advisors to the Ad Hoc Bondholder Committee within ten (10) Business Days of the execution of this Agreement; provided, however, that the information contained therein shall be maintained as confidential by the Company and the Company’s financial advisors and legal counsel, except to the extent otherwise required by law or any rule or regulation of any exchange or regulatory authority; provided, further, however that subject to the disclosure obligations set forth in Section 28 of this Agreement, DI and the Company may disclose the aggregate amount of Noteholder Claims held by all Consenting Noteholders party to this Agreement; and

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(b)                                 other than pursuant to this Agreement, such Noteholder Claims, are free and clear of any pledge, lien, security interest, charge, claim, equity, option, proxy, voting restriction, right of first refusal or other limitation on disposition or encumbrances of any kind, that might adversely affect in any way such Consenting Noteholder’s performance of its obligations contained in this Agreement at the time such obligations are required to be performed.

10.           Representations.

(a)                            Each Party represents to each other Party that, as of the date of this Agreement:

(i) It has all requisite corporate, partnership, limited liability company or similar authority to enter into this Agreement and carry out the transactions contemplated hereby and perform its obligations hereunder, and the execution, delivery and performance of such Party’s obligations hereunder have been duly authorized by all necessary corporate, partnership, limited liability, or similar action on its part;

(ii) The execution, delivery and performance of this Agreement by such Party does not and shall not (x) violate any provision of law, rule or regulation applicable to it or any of its subsidiaries or its organizational documents or those of any of its subsidiaries or (y) conflict with, result in a breach of or constitute (with due notice or lapse of time or both) a default under any material contractual obligations to which it or any of its subsidiaries is a party or under its organizational documents;

(iii) The execution, delivery and performance by it of this Agreement does not and shall not require any registration or filing with, consent or approval of, or notice to, or other action to, with or by, any federal, state or other governmental authority or regulatory body, except such filing as may be necessary and/or required for disclosure by the Securities and Exchange Commission or pursuant to state securities or “blue sky” laws, and the approval by the Bankruptcy Court of the Company’s authority to enter into and implement this Agreement;

(iv) Subject to the provisions of sections 1125 and 1126 of the Bankruptcy Code, this Agreement is the legally valid and binding obligation of such Party, enforceable against it in accordance with its terms, except as enforcement may be limited by bankruptcy, insolvency, reorganization, moratorium or other similar laws, both foreign and domestic, relating to or limiting creditors’ rights generally or by equitable principles relating to enforceability.

(b)           Each Consenting Noteholder represents to the Company that such Consenting Noteholder, in entering into this Agreement and undertaking its obligations hereunder, is acting independently and is not acting, directly or indirectly, through contract, arrangement, understanding, relationship or otherwise with any other holder of Notes.

11.           Entire Agreement.  This Agreement, including the exhibits, schedules and annexes hereto constitutes the entire agreement of the Parties with respect to the subject matter of this Agreement, and supersedes all other prior negotiations, agreements and understandings, whether written or oral, among the Parties with respect to the subject matter of this Agreement.

12.           Waiver.  This Agreement and the Restructuring Term Sheet are part of a proposed settlement of a dispute among the Parties. If the transactions contemplated by this Agreement are

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or are not consummated, or following the occurrence of the Termination Date, if applicable, nothing shall be construed by this Agreement as a waiver by any Party of any or all of such Party’s rights and the Parties expressly reserve any and all of their respective rights.  Pursuant to Federal Rule of Evidence 408 and any other applicable rules of evidence, this Agreement and all negotiations relating hereto shall not be admissible into evidence in any proceeding other than a proceeding to enforce its terms.

13.           Service on Committee.  Notwithstanding anything in this Agreement to the contrary, if any Consenting Noteholder is appointed to, and serves on, an official committee of unsecured creditors in the Chapter 11 Cases, then the terms of this Agreement shall not be construed to limit such Consenting Noteholder’s exercise of fiduciary duties in its role as a member of such committee, and any exercise of such fiduciary duties shall not be deemed to constitute a breach of the terms of this Agreement; provided, however, that service as a member of any such committee shall not relieve such Consenting Noteholder in its non-committee capacity of its obligations to affirmatively support, and vote for, the Plan, on the terms and conditions set forth in this Agreement.

14.           Company Fiduciary Duties.  Notwithstanding anything to the contrary in this Agreement, nothing in this Agreement shall require the Company or its subsidiaries or any of its or their respective directors or officers (in such person’s capacity as a director or officer) to take any action, or to refrain from taking any action, to the extent that taking such action or refraining from taking such action would be inconsistent with such person’s fiduciary obligations under applicable law.

15.           Cooperation and Support.  The Parties shall cooperate with each other in good faith and shall coordinate their activities (to the extent possible and subject to the terms of this Agreement) in respect of (i) all matters relating to their rights hereunder in respect of the Company or otherwise in connection with their relationship with the Company, and (ii) the consummation of the Restructuring.  Furthermore, subject to the terms of this Agreement, each of the Parties shall take such action as reasonably may be necessary to carry out the purposes and intent of this Agreement, including making and filing any required regulatory filings and voting any claims or securities of the Company in favor of the Restructuring in connection therewith, and shall refrain from taking any action that would frustrate the purposes and intent of this Agreement.  In addition, DI and the Company will use its reasonable best efforts to provide draft copies of all Plan Related Documents to counsel to the Consenting Noteholders prior to filing such pleadings and/or documents.

16.           Suspension of Litigation.  The Parties shall continue, until such time as a Termination Date occurs, their stipulated suspension of the prosecution of the Consenting Noteholders’ complaint and postponement of any time period to respond in the Supreme Court of the State of New York, County of New York, captioned Avenue Investments, L.P. et al v. Dynegy Inc., Dynegy Holdings, LLC, Dynegy Gas Investments, LLC, Clint C. Freeland, Kevin T. Howell and Robert C. Flexon (Index No. 652599/11).  The Consenting Noteholders further agree that the Plan shall include a release of all claims of the Consenting Noteholders related to the subject matter of such litigation and a covenant not to sue.

17.           Representation by Counsel.  Each Party hereto acknowledges that it has been represented by counsel (or had the opportunity to and waived its right to do so) in connection with this Agreement and the transactions contemplated by this Agreement. Accordingly, any rule

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of law or any legal decision that would provide any Party hereto with a defense to the enforcement of the terms of this Agreement against such Party based upon lack of legal counsel shall have no application and is expressly waived.  The provisions of this Agreement shall be interpreted in a reasonable manner to effect the intent of the Parties hereto.  None of the Parties hereto shall have any term or provision construed against such Party solely by reason of such Party having drafted the same.

18.           Independent Due Diligence and Decision-Making.  Each Consenting Noteholder hereby confirms that its decision to execute this Agreement has been based upon its independent investigation of the operations, businesses, financial and other conditions and prospects of the Company and DI.

19.           Counterparts.  This Agreement may be executed in one or more counterparts, each of which, when so executed, shall constitute the same instrument and the counterparts may be delivered by facsimile transmission or by electronic mail in portable document format (.pdf).

20.           Amendments.  Except as otherwise provided in this Agreement, this Agreement may not be modified, amended or supplemented without prior written consent of each of DI, the Company and a Majority of the Consenting Noteholders; provided that neither Section 6 nor any economic or other material term of the Restructuring Term Sheet shall be modified, amended or supplemented in a manner that is adverse to any Consenting Noteholder without prior written consent of such Consenting Noteholder.

21.           Headings.  The headings of the sections, paragraphs and subsections of this Agreement are inserted for convenience only and shall not affect the interpretation of this Agreement.

22.           Relationship Among Parties.  Notwithstanding anything in this Agreement to the contrary, the duties and obligations of the Consenting Noteholders under this Agreement shall be several, not joint.  No Party hereto shall have any responsibility for any trading of Noteholder Claims by any other entity by virtue of this Agreement.  No prior history, pattern or practice of sharing confidences among or between Parties hereto shall in any way affect or negate this understanding and agreement.

23.           Specific Performance.  It is understood and agreed by the Parties that money damages would be an insufficient remedy for any breach of this Agreement by any Party and each non-breaching Party shall be entitled to specific performance and injunctive or other equitable relief as a remedy of any such breach, including, without limitation, an order of the Bankruptcy Court or other court of competent jurisdiction requiring any Party to comply promptly with any of its obligations hereunder; provided, however, that each Party agrees to waive any requirement for the securing or posting of a bond in connection with such remedy.

24.           Governing Law.  This Agreement shall be governed by, and construed in accordance with, the laws of the State of New York, without regard to such state’s choice of law provisions which would require the application of the law of any other jurisdiction. By its execution and delivery of this Agreement, each of the Parties irrevocably and unconditionally agrees for itself that the Bankruptcy Court shall have exclusive jurisdiction of all matters arising out of or in connection with this Agreement, and each of the Parties irrevocably accepts and

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submits itself to the exclusive jurisdiction of such court, generally and unconditionally, with respect to such matters.

25.           Notices.  All notices, requests and other communications hereunder must be in writing and will be deemed to have been duly given only if delivered personally, by !email, courier, by facsimile transmission or mailed (first class postage prepaid) to the parties at the following addresses, emails or facsimile numbers:

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26.           No Third-Party Beneficiaries. The terms and provisions of this Agreement are intended solely for the benefit of the Parties hereto and their respective successors and permitted assigns, and it is not the intention of the Parties to confer third-party beneficiary rights upon any other Person.

27.           Successors and Assigns.  Except as otherwise provided in this Agreement, this Agreement is intended to bind and inure to the benefit of each of the Parties and each of their respective successors, assigns, heirs, executors, administrators and representatives.

28.           Public Disclosure. Without limiting the prohibition on disclosure of the Disclosure Certificate contained in this Agreement, the Consenting Noteholders hereby consent to the disclosure by DI or the Company in the Plan, Disclosure Statement, the other Plan Related Documents and any filings by the Company with the Bankruptcy Court or the Securities and Exchange Commission or as required by law or regulation of the execution and contents of this Agreement; provided, however, that except as required by law or any rule or regulation of any securities exchange or any governmental agency, neither DI nor the Company shall use the name of any Consenting Noteholder or its controlled affiliates, officers, directors, managers, stockholders, members, employees, partners, representatives and agents in any press release or filing with the Securities and Exchange Commission without the Consenting Noteholder’s prior consent.  Each of DI and the Company, on the one hand, and the Ad Hoc Bondholder Committee, on the other hand, shall (a) consult with each other before issuing any press release or otherwise making any public statement with respect to the transactions contemplated by this Agreement, (b) provide to the other for review a copy of any such press release or public statement and (c) not issue any such press release or make any such public statement prior to such consultation and review and the receipt of the prior consent of the other Party, unless required by applicable law or regulations of any applicable stock exchange or governmental authority, in which case, the Party required to issue the press release or make the public statement shall, prior to issuing such press release or making such public statement, use its commercially reasonable efforts to allow the other Party reasonable time to comment on such release or statement to the extent practicable; provided, that no Party need consult with any other Party with respect to any press release or public statement relating to the termination of this Agreement.

29.           Interpretation.  This Agreement is the product of negotiations among the Parties, and the enforcement or interpretation of this Agreement is to be interpreted in a neutral manner; and any presumption with regard to interpretation for or against any Party by reason of that Party having drafted or caused to be drafted this Agreement or any portion of this Agreement, shall not be effective in regard to the interpretation of this Agreement.

30.           Completion of Plan Related Documents.  The Parties agree that certain Plan Related Documents (which for purposes of this Section 30 shall not include, among other things, (i) the Confirmation Order, (ii) New Secured Notes Indenture (other than the description of the notes in connection therewith), and (iii) those appendices, amendments, modifications, supplements, exhibits and schedules to the Plan or Disclosure Statement that DI, DH and a

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Majority of the Consenting Noteholders agree may be filed later) as of December 26, 2011, reflect the material economic terms set forth in the Restructuring Term Sheet.  The Parties further agree that additional modifications may be necessary to the contractual terms of certain of the Plan Related Documents to fully reflect the intent of the Parties and each Party shall work in good faith to negotiate any such modification requested by another Party such that the final form and substance of all Plan Related Documents are reasonably acceptable to DI, the Company and a Majority of the Consenting Noteholders.

31.           Subordinated Notes.  The Parties have agreed that the Plan Related Documents shall be modified to provide (i) that holders of Subordinated Notes shall receive an allowed claim of $0.35 for each $1.00 of principal amount of Subordinated Notes, which allowed claim will receive the same recovery as allowed claims held by holders of Senior Notes and (ii) that the aggregate principal amount of the DI 11% New Secured Notes due 2018 issued pursuant to the New Secured Notes Indenture shall be increased by $15,000,000.   The Parties further agree that the Plan Related Documents may be further modified to provide holders of Subordinated Notes with an option to have their Subordinated Notes reinstated, subject to the existing contractual subordination rights of, inter alia, holders of the Senior Notes, or to have an allowed claim treated as set forth in the first sentence of this Section 31.  Each holder of Subordinated Notes shall (x) elect the treatment set forth in clause (i) of the first sentence of this Section 31 and (y) have the benefit of any other treatment election option provided to holders of Subordinated Notes under the Plan Related Documents except that they shall not elect any reinstatement option so long as they have the option to receive the treatment set forth in clause (i) of the first sentence of this Section 31.

32.           Fees and Expenses.  Within ten (10) Business Days of demand, DI shall pay all reasonable and documented fees and expenses of the advisors to the Ad Hoc Bondholder Committee and of each of the Consenting Noteholders.

[REST OF PAGE INTENTIONALLY LEFT BLANK]

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IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed on the date first written above.

SCHEDULE I

Consenting Noteholders:

AEGON USA Investment Management, LLC

Avenue Capital Group

Caspian Capital L.P.

Franklin Advisors, Inc.

Loomis, Sayles & Company, L.P.

Notice Information:

AEGON USA Investment Management, LLC
230 West Monroe, Suite 1450
Chicago, IL 60606
Fax: (800) 454-2664
Attn: Jim Schaeffer
Email: jschaeffer@aegonusa.com

Avenue Capital Group
399 Park Avenue, 6th Floor
New York, NY 10022
Fax: 212-850-7506
Attn: Stephen Burnazian and Matthew Kimble
Email: sburnazian@avenuecapital.com; mkimble@avenuecapital.com

Caspian Capital L.P.
767 Fifth Avenue, 45th Floor
New York, NY 10153
Fax: (212) 826-6980
Attn: Adam S. Cohen, Greg Saiontz
Email: adam@caspianlp.com; greg@caspianlp.com

Franklin Advisors, Inc.
One Franklin Templeton Investments
Fax: (916) 463-1902
Attn: Ed Perks
Email: perksed@frk.com

Loomis, Sayles & Company, L.P.
One Financial Center
Boston, MA 02111
Attn:  Thomas Day
Email: tday@loomissayles.com

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Exhibit A to the Amended and Restated Restructuring Support Agreement

Restructuring Term Sheet

DATED 12/27/2011

Dynegy Restructuring Proposal

(1)  Individual holders shall have the option to apply any recovery received to satisfy outstanding principal or interest, as such allocation is determined by the holder in its sole discretion.

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Exhibit B to the Amended and Restated Restructuring Support Agreement

Form of Disclosure Certificate

The undersigned hereby certifies, in his or her capacity as an officer of the Consenting Noteholder identified below and not in his or her individual or personal capacity, that the Consenting Noteholder or its affiliate is the legal owner, beneficial owner and/or investment advisor or manager for the Noteholder Claims set forth on Schedule I.