PROXY STATEMENT

GENERAL INFORMATION

INFORMATION ABOUT THE ANNUAL MEETING AND VOTING

Proxy Materials

Why did I receive these Proxy Materials?

Our Board of Directors has made these materials available to you on the internet, or, upon your request, has delivered printed proxy materials to you, in connection with the solicitation of proxies for use at Ambac’s 2013 Annual Meeting of Stockholders, which will take place on December 18, 2013 at 12:00 p.m. (Eastern). The meeting will be held via the internet at www.virtualshareholdermeeting.com/AMBC. As a stockholder, you are invited to attend the Annual Meeting and are requested to vote on the items of business described in this Proxy Statement. This Proxy Statement includes information that we are required to provide to you under SEC rules and that is designed to assist you in voting your shares.

Why did I receive a notice in the mail regarding the internet availability of proxy materials instead of a full set of proxy materials?

In accordance with rules adopted by the SEC, we may furnish proxy materials, including this Proxy Statement and our 2012 Annual Report to Stockholders, to our stockholders by providing access to such documents on the internet instead of mailing printed copies. Stockholders will not receive printed copies of the proxy materials unless they request them. Instead, the Internet Notice, which was mailed to our stockholders, will instruct you as to how you may access and review all of the proxy materials on the internet. The Internet Notice also instructs you as to how you may submit your proxy on the internet, by phone or by mail. If you would like to receive a paper or email copy of our proxy materials, you should follow the instructions for requesting such materials in the Internet Notice.

What is included in the proxy materials?

The proxy materials include:

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How can I access the proxy materials over the internet?

The Internet Notice, proxy card or voting instruction card will contain instructions on how to:

Our proxy materials are also available at www.proxyvote.com .

Choosing to receive your future proxy materials by email will save us the cost of printing and mailing documents to you, and will reduce the impact on the environment of printing and mailing these materials. If you choose to receive future proxy materials by email, you will receive an email next year with instructions containing a link to those materials and a link to the proxy voting site. Your election to receive proxy materials by email will remain in effect until you terminate it.

What information is contained in this Proxy Statement?

The information in this Proxy Statement relates to the proposals to be voted on at the Annual Meeting and details regarding the voting process, the compensation of our directors and certain of our executive officers, corporate governance, and certain other required information.

Why did I only receive one set of materials when there is more than one stockholder at my address?

If two or more stockholders share one address, each such stockholder may not receive a separate copy of our Annual Report, Proxy Statement or Internet Notice. Stockholders who do not receive a separate copy of our Annual Report, Proxy Statement or Internet Notice and want to receive a separate copy may request to receive a separate copy of, or additional copies of, our Annual Report, Proxy Statement or Internet Notice via the internet, phone or email, as outlined above. Stockholders who share an address and receive multiple copies of our Annual Report, Proxy Statement or Internet Notice may also request to receive a single copy by writing to our Investor Relations Department, Ambac Financial Group, Inc., One State Street Plaza, New York, New York 10004.

Voting Information

What items of business will be voted on at the Annual Meeting?

The items of business scheduled to be voted on at the Annual Meeting are:

We will also consider any other business that properly comes before the Annual Meeting.

Why is the Annual Meeting being held now?

Ambac historically held its annual meeting of stockholders in May of each year. However, following its filing a voluntary petition for relief under Chapter 11 of the United States Bankruptcy Code, an annual meeting was not held due to the expense of holding such a meeting and the uncertainties relating to the bankruptcy filing. On May 1, 2013, Ambac emerged from bankruptcy, and our directors were appointed as interim directors as part of that process (as described in more detail herein). We are holding this meeting because our directors believe that it is crucial that stockholders have input into who constitutes

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the Board that is overseeing our operations. In addition, the Board is seeking stockholder approval of Ambac’s 2013 Incentive Compensation Plan, which is designed to further align incentives for management with the interests of stockholders. As a result, the Board believes that it is in the best interests of Ambac and its stockholders to have the meeting as soon as possible and not wait for the normal meeting schedule to resume in 2014.

How does the Board of Directors recommend that I vote?

Our Board of Directors recommends that you vote your shares:

Other than the five items of business described in this Proxy Statement, we are not aware of any other business to be acted upon at the Annual Meeting. If you grant a proxy, the persons named as proxy holders, Stephen M. Ksenak and Sara Copland, or either of them, will have the discretion to vote your shares on any additional matters properly presented for a vote at the meeting.

What shares can I vote?

Each share of Ambac common stock issued and outstanding as of the close of business on the Record Date for the 2013 Annual Meeting of Stockholders is entitled to be voted on all items being voted on at the Annual Meeting. You may vote all shares owned by you as of the Record Date, including (i) shares held directly in your name as the stockholder of record, and (ii) shares held for you as the beneficial owner in street name through a broker, bank, trustee, or other nominee. On the Record Date, we had 45,002,524 shares of common stock issued and outstanding.

How many votes am I entitled to per share?

Each holder of shares of common stock is entitled to one vote for each share of common stock held as of the Record Date. The voting rights of certain substantial holders (those owning 10% or more) of common stock are restricted. A substantial holder (including any group consisting of such holder and any other person with whom such holder or any affiliate or associate of such holder has any agreement, contract, arrangement or understanding with respect to acquiring, voting, holding or disposing of our common stock) will be entitled to vote only such number of shares that would equal (after giving effect to this restriction) one vote less than 10% of the votes entitled to be cast by all holders of outstanding common stock. This restriction does not apply if the acquisition or ownership of common stock has been approved, whether before or after such acquisition or first time of ownership, by the Wisconsin Insurance Commissioner. Our certificate of incorporation also restricts the right of certain transferees to vote certain of their shares to the extent that, as a result of such transfer (or any series of transfers of which such transfer is a part), either (i) any person or group of persons shall become a five-percent stockholder or (ii) the percentage stock ownership interest in our shares of any five-percent stockholder shall be increased.

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What is the difference between holding shares as a stockholder of record and as a beneficial owner?

Most Ambac stockholders hold their shares as a beneficial owner through a broker or other nominee rather than directly in their own name. If your shares are registered directly in your name with our transfer agent, Computershare Trust Company, N.A., you are considered, with respect to those shares, the stockholder of record. If your shares are held in an account at a brokerage firm, bank, broker-dealer, trust, or other similar organization, like the vast majority of our stockholders, you are considered the beneficial owner of shares held in street name.

How can I vote my shares at the Annual Meeting?

Shares held in your name as the stockholder of record or held beneficially in street name may be voted by you by internet at the Annual Meeting. Even if you plan to attend the Annual Meeting, we recommend that you also submit your proxy or voting instructions as described below so that your vote will be counted if you later decide not to attend the meeting.

How can I vote my shares without attending the Annual Meeting?

Whether you hold shares directly as the stockholder of record or beneficially in street name, you may direct how your shares are voted without attending the Annual Meeting. You can vote by proxy over the internet or by phone by following the instructions provided in the Internet Notice, or, if you requested to receive printed proxy materials, you can also vote by mail pursuant to instructions provided on the proxy card.

Can I change my vote or revoke my proxy?

You may change your vote at any time prior to the taking of the vote at the Annual Meeting. You may change your vote by (i) granting a new proxy bearing a later date (which automatically revokes the earlier proxy) using any of the methods described above (and until the applicable deadline for each method), (ii) providing a written notice of revocation to Ambac’s Corporate Secretary at Ambac Financial Group, Inc., One State Street Plaza, New York, New York 10004 (and you can send a copy via email to corporatesecretary@ambac.com), prior to your shares being voted, or (iii) attending the Annual Meeting and voting by internet. Attendance at the meeting will not cause your previously granted proxy to be revoked unless you specifically so request or vote by internet at the Annual Meeting.

Is my vote confidential?

Proxy instructions, ballots and voting tabulations that identify individual stockholders are handled in a manner that protects your voting privacy. Your vote will not be disclosed either within Ambac or to third parties, except:

How many shares must be present or represented to conduct business at the Annual Meeting?

The quorum requirement for holding the Annual Meeting and transacting business is that holders of a majority of the voting power of Ambac’s shares of common stock outstanding as of the Record Date must be present or represented by proxy. Both abstentions and broker non-votes (described below) are counted for the purpose of determining the presence of a quorum.

How are votes counted?

In the election of directors (Proposal Number 1), you may vote “FOR” all or some of the nominees or your vote may be “WITHHELD” with respect to one or more of the nominees.

For the other items of business, you may vote “FOR,” “AGAINST,” or “ABSTAIN.” If you elect to “ABSTAIN,” the abstention has the same effect as a vote “AGAINST.”

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If you provide specific instructions with regard to certain items, your shares will be voted as you instruct on such items. If no instructions are indicated, the shares will be voted as recommended by the Board of Directors.

What is the voting requirement to approve each of the proposals?

The directors are elected by a plurality of the shares of common stock present or represented by proxy and entitled to vote on the election of directors. This means that the five individuals nominated for election to the Board who receive the most “FOR” votes among votes properly cast will be elected. Only “FOR” or “WITHHELD” votes are counted in determining whether a plurality has been cast in favor of a director nominee. A “WITHHELD” vote will have the same effect as a vote AGAINST the election of a director nominee. You cannot abstain in the election of directors and broker non-votes are not counted. Each holder of our common stock is entitled to one vote for each share held and does not have cumulative voting rights. A substantial holder (including any group consisting of such holder and any other person with whom such holder or any affiliate or associate of such holder has any agreement, contract, arrangement or understanding with respect to acquiring, voting, holding or disposing of our common stock) will be entitled to vote only such number of shares that would equal (after giving effect to this restriction) one vote less than 10% of the votes entitled to be cast by all holders of outstanding common stock. This restriction does not apply if the acquisition or ownership of common stock has been approved, whether before or after such acquisition or first time of ownership, by the Wisconsin Insurance Commissioner. Our certificate of incorporation also restricts the right of certain transferees to vote certain of their shares to the extent that, as a result of such transfer (or any series of transfers of which such transfer is a part), either (i) any person or group of persons shall become a five-percent stockholder or (ii) the percentage stock ownership interest in our shares of any five-percent stockholder shall be increased.

The approval of the remaining four proposals described below requires the affirmative “FOR” vote of the holders of a majority of the voting power of Ambac’s shares of common stock present or represented by proxy at the Annual Meeting and entitled to vote thereon, voting together as a single class:

If you hold shares beneficially in street name and do not vote your shares as described in this Proxy Statement, your shares may constitute “broker non-votes.” Broker non-votes occur on a matter when a broker is not permitted to vote on that matter without instructions from the beneficial owner and instructions are not given. These matters are referred to as “non-routine” matters. All of the matters scheduled to be voted on at the Annual Meeting are “non-routine,” except for the proposal to ratify the appointment of KPMG LLP as Ambac’s independent registered public accounting firm for the fiscal year ending December 31, 2013. In tabulating the voting result for any particular proposal, shares that constitute broker non-votes are not considered voting power present with respect to that proposal. Thus, broker non-votes will not affect the outcome of any matter being voted on at the meeting, assuming that a quorum is obtained. Abstentions are considered voting power present at the meeting and thus will have the same effect as votes against each of the matters scheduled to be voted on at the Annual Meeting (other than the election of directors).

Please note that the rules regarding how brokers may vote your shares have changed. Brokers may no longer vote your shares on the election of directors, certain executive compensation matters, or certain corporate governance matters in the absence of your specific instructions as to how to vote so we encourage you to provide instructions to your broker regarding the voting of your shares.

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Who will bear the cost of soliciting votes for the Annual Meeting?

Ambac pays the entire cost of preparing, assembling, printing, mailing, and distributing these proxy materials and soliciting votes. If you choose to access the proxy materials and/or vote over the internet, you are responsible for internet access charges you may incur. If you chose to vote by phone, you are responsible for any phone charges you may incur. In addition to the mailing of these proxy materials, the solicitation of proxies or votes may be made in person, by telephone, or by electronic communication by our directors, officers, and employees, who will not receive any additional compensation for such solicitation activities.

What happens if additional matters are presented at the Annual Meeting?

Other than the five items of business described in this Proxy Statement, we are not aware of any other business to be acted upon at the Annual Meeting. If you grant a proxy, the persons named as proxy holders, Stephen M. Ksenak or Sara Copland, will have the discretion to vote your shares on any additional matters properly presented for a vote at the meeting. If for any reason, any of the nominees is not available as a candidate for director, the persons named as proxy holders will vote your proxy for such other candidate or candidates as may be nominated by the Board of Directors.

Where can I find the voting results of the Annual Meeting?

We will announce preliminary voting results at the Annual Meeting and publish final voting results in the Annual Meeting of Stockholders section of our Investor Relations website at http://ir.ambac.com. We will also disclose the final voting results on a Current Report on Form 8-K filed with the SEC within four business days of the Annual Meeting.

Attending the Annual Meeting

How can I attend the Annual Meeting?

You are entitled to attend the Annual Meeting only if you were an Ambac stockholder as of the Record Date or you hold a valid proxy for the Annual Meeting. The meeting will begin promptly at 12:00 p.m. (Eastern). We encourage you to access the meeting online prior to its start time. Instructions on how to attend and participate via the internet are posted at www.proxyvote.com. Stockholders may vote and submit questions while attending the meeting on the internet.

Do Directors Attend the Annual Meeting?

Ambac encourages directors to attend Ambac’s Annual Meeting of Stockholders. We did not hold an annual meeting in 2012, but expect that each of our Board members will attend the 2013 Annual Meeting.

How can I find out if I am a stockholder of record entitled to vote?

For a period of at least ten days before the Annual Meeting, a complete list of stockholders of record entitled to vote at the Annual Meeting will be available during ordinary business hours at our principal executive offices at One State Street Plaza, New York, New York 10004, Attention: Corporate Secretary, for inspection by stockholders of record for proper purposes.

Other Questions related to the Meeting or Ambac

Who will serve as inspector of elections?

The inspectors of election will be representatives from Broadridge Financial Solutions, Inc.

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How can I contact Ambac’s transfer agent?

Contact our transfer agent by either writing to Computershare Trust Company, N.A., PO Box 43006, Providence, RI 02940-3006, or 250 Royall Street, Canton, MA 02021, or by telephoning 1-800-662-7232 or via the web at www.computershare.com/investor.

Whom Should I Call If I Have Any Questions?

If you have any questions about the Annual Meeting or voting, please contact Stephen M. Ksenak, Corporate Secretary, at (212) 658-7470 or at corporatesecretary@ambac.com. If you have any questions about your ownership of Ambac common stock, please contact Michael Fitzgerald, Managing Director, Investor Relations, at (212) 658-7470 or at mfitzgerald@ambac.com.

How can a stockholder communicate directly with our Board?

Stockholders and other interested parties may communicate with Ambac’s Board by writing to Ambac’s Corporate Secretary at Ambac Financial Group, Inc., One State Street Plaza, New York, New York 10004 or by sending an e-mail to Ambac’s Corporate Secretary at corporatesecretary@ambac.com. Ambac’s Corporate Secretary will then forward your questions or comments directly to the Board.

Please note that material that is directly or indirectly hostile or threatening, illegal or otherwise unsuitable will not be forwarded. Any communication that is relevant to Ambac’s business and is not forwarded will be retained for one year and will be made available to the independent directors on request. The independent directors grant the Corporate Secretary discretion to decide what correspondence shall be shared with Ambac management and specifically instruct that any personal employee complaints be forwarded to our Human Resources Department.

What is the deadline to propose actions for consideration at next year’s Annual Meeting of Stockholders or to nominate individuals to serve as directors?

Stockholder Proposals : Stockholders may present proper proposals for inclusion in our proxy statement and for consideration at the next annual meeting of stockholders by submitting their proposals in writing to Ambac’s Corporate Secretary in a timely manner. For a stockholder proposal to be considered for inclusion in our proxy statement for our 2014 Annual Meeting of Stockholders, the proposal must be delivered to or mailed and received at our offices not less than 60 days nor more than 90 days prior to the meeting; provided, that if less than 70 days’ notice of the meeting is given to stockholders, notice by a stockholder must be received not later than the close of business on the 10 ^th day following the day on which such notice of the meeting date was mailed or public disclosure was made. Each such notice shall set forth as to each proposal: (i) a brief description of the proposal and the reasons for making such proposal at the annual meeting, (ii) the name and address, as they appear on our books, of the stockholder making such proposal, (iii) the class and number of shares of common stock which are beneficially owned by such stockholder and (iv) any material interest of the stockholder in such proposal. The presiding officer of an annual meeting shall, if the facts warrant, determine and declare to the meeting that a proposal was not properly brought before the meeting and, if so determined, such proposal will not be presented. Notwithstanding the foregoing, a stockholder seeking to have a proposal included in a proxy statement shall comply with the requirements of Regulation 14A under the Securities Exchange Act of 1934, as amended (including, but not limited to, Rule 14a-8 or its successor provision).

Nomination of Director Candidates : You may propose director candidates for consideration by our Governance and Nominating Committee for our 2014 Annual Meeting of Stockholders. For a director nomination to be considered for inclusion in our proxy statement for our 2014 Annual Meeting of Stockholders, the proposal must be delivered to or mailed and received at our offices not less than 60 days nor more than 90 days prior to the meeting; provided, that if less than 70 days’ notice of the meeting is given to stockholders, notice by a stockholder must be received not later than the close of business on the 10 ^th day following the day on which such notice of the meeting date was mailed or public disclosure was made. Any such recommendations should include (i) the name, residence and business address of the nominating stockholder, (ii) a representation that the stockholder is a record holder or beneficial

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holder of our voting shares and a statement of the number of such shares, (iii) a representation that the stockholder intends to be present or appear by proxy at the meeting to nominate the individuals specified in the notice, if the nominations are to be made at a meeting of stockholders, (iv) information regarding each nominee such as would be required to be included in a proxy statement or is otherwise required, in each case pursuant to Regulation 14A under the Securities Exchange Act of 1934, as amended, (v) a description of all arrangements or understandings between and among the stockholder and each and every nominee and (vi) the written consent of each nominee to serve as a director, if elected. In the case of a nomination that does not conform to such requirements, the presiding officer of the meeting shall, if the facts warrant, determine and declare at the meeting that such nomination was not made in accordance with the foregoing procedures and, if so determined, the defective nomination shall be disregarded.

INCORPORATION BY REFERENCE

To the extent that this Proxy Statement has been or will be specifically incorporated by reference into any other filing of Ambac under the Securities Act of 1933, as amended, or the Securities Exchange Act of 1934, as amended (“Exchange Act”), the sections of this Proxy Statement titled “Report of the Audit Committee of the Board of Directors” (to the extent permitted by the rules of the U.S. Securities and Exchange Commission (“SEC”)) shall not be deemed to be so incorporated, unless specifically provided otherwise in such filing.

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DIRECTORS, EXECUTIVE OFFICERS, AND CORPORATE GOVERNANCE

Emergence from Bankruptcy; Reconstituted Board of Directors

On November 8, 2010, Ambac filed a voluntary petition for relief under Chapter 11 of the United States Bankruptcy Code (“Bankruptcy Code”) in the United States Bankruptcy Court for the Southern District of New York (“Bankruptcy Court”). Ambac, as debtor and debtor-in-possession, filed a Fifth Amended Plan of Reorganization on March 12, 2012, which was confirmed by order of the Bankruptcy Court on March 14, 2012 and modified in accordance with orders entered by the Bankruptcy Court on April 29, 2013 (such Fifth Amended Plan of Reorganization, as so modified, the “Reorganization Plan”). On May 1, 2013 (the “Effective Date”), the Reorganization Plan became effective and Ambac emerged from bankruptcy.

Pursuant to the Reorganization Plan, on May 1, 2013, Messrs. Michael A. Callen, Paul R. DeRosa, Philip N. Duff, Thomas C. Theobald, Henry D.G. Wallace and David W. Wallis and Mses. Jill M. Considine and Laura S. Unger departed from the Board (“Pre-Emergence Board”). The Reorganization Plan provided for three directors to be appointed by the official committee of unsecured creditors (“Creditors’ Committee”) and one director to be appointed by a group of unaffiliated holders of certain senior debt securities of Ambac (the “Informal Group”) commencing on the Effective Date. Messrs. Victor Mandel and Nader Tavakoli were appointed by the Creditors’ Committee and Mr. Jeffrey S. Stein was appointed by the Informal Group. In addition, Mr. Eugene M. Bullis was appointed to the Board on May 31, 2013 as the last of the three directors nominated by the Creditors’ Committee. Ms. Diana N. Adams, our Chief Executive Officer, continued to serve on the Board after our emergence from bankruptcy. Further, in accordance with the Reorganization Plan, our certificate of incorporation and by-laws were amended and restated in their entirety.

On July 12, 2012, we entered into a Consultant Agreement with the Official Committee of Unsecured Creditors of Ambac Financial Group, Inc. (the “Official Committee”) and Messrs. Nader Tavakoli, Victor Mandel and Jeffrey S. Stein to promote an efficient transition between the Pre-Emergence Board and the current Board and to effectuate an orderly emergence from Chapter 11 on the Effective Date. Under this agreement, Messrs. Nader Tavakoli, Victor Mandel and Jeffrey S. Stein (i) reviewed and analyzed our business, assets, liabilities, operations, cash flows, properties, financial condition and prospects of our operations and strategic issues, (ii) attended informational sessions with management and members of the Pre-Emergence Board from time to time, (iii) attended meetings with members of the Pre-Emergence Board to discuss business and other company issues, and (iv) advised the Official Committee on information learned during their observations and interactions with management and the Pre-Emergence Board. As a result, Messrs. Nader Tavakoli, Victor Mandel and Jeffrey S. Stein obtained significant institutional knowledge with respect to Ambac and all aspects of its business.

Board of Directors

The Board oversees the business of Ambac and monitors the performance of management. Addressing issues following Ambac’s emergence from Chapter 11 and the challenges confronting our principal operating subsidiary, Ambac Assurance Corporation, a financial guarantee insurance company (“Ambac Assurance”), requires a high level of focus, time commitment and engagement from the directors. The Board usually meets 5 times per year in regularly scheduled meetings, but will meet more often, if necessary. On and following the Effective Date and as of October 31, 2013, the Board met 9 times. Outside of formal meetings, directors frequently engage with management concerning Ambac’s business and strategies.

Four of our current independent directors (Messrs. Bullis, Mandel, Stein and Tavakoli), as well as Ms. Adams, our Chief Executive Officer, also serve as directors of Ambac Assurance.

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Diana N. Adams has been a Director, President and Chief Executive Officer of Ambac and Ambac Assurance since July 2011. From August 2010 until June 2011, Ms. Adams served as the Chief Administrative Officer for Ambac, with executive responsibility for Ambac’s human resources, technology and corporate administration departments. In addition, from June 2008 to June 2011, Ms. Adams served as a Senior Managing Director with executive responsibility for Ambac’s International business and for the Structured Finance business which she wound down in 2009 and she was also responsible for overseeing human resources and administration from May 2009 to June 2010. Ms. Adams served as a director of Ambac Assurance UK Limited, Ambac’s international financial guarantee subsidiary, from September 2008 to December 2008 and thereafter was Chairman of the Board through August 2010. Prior to that, Ms. Adams had been Managing Director of Emerging Markets, Structured Insurance and Student Loans. Ms. Adams joined Ambac in 2000 as the head of Emerging Markets following the winding down of the international joint venture between Ambac and MBIA, where she had worked. From 1993-1999, Ms. Adams worked at JP Morgan first in the Capital Markets division and then in the Structured Products division. From 1990-1993 Ms. Adams worked for Mitsubishi Bank in Leveraged and Acquisition Finance. From 1988-1990 Ms. Adams worked at Merrill Lynch in the Investment Banking division.

Eugene M. Bullis has been a director since May 31, 2013. Since December 2010, Mr. Bullis has served on the Board of Governors of The Doctors Company, an insurance interexchange that is the nation’s second largest provider of professional liability insurance for physicians. From 2007 to 2010, Mr. Bullis served as an Executive Vice President and Chief Financial Officer of The Hanover Insurance Group, Inc. (THG). Prior to joining THG, Mr. Bullis served as Executive Vice President and Chief Financial Officer at Conseco, Inc., from 2002 to 2007. Previously, Mr. Bullis served in a number of senior financial officer roles in technology-related businesses, including Chief Financial Officer of Wang Laboratories, Inc. Mr. Bullis began his career with a predecessor firm of what is now Ernst & Young LLP, where he advanced to audit partner with a concentration in services to insurance company clients.

Victor Mandel has been Co-Chair and a Director since May 1, 2013. Mr. Mandel has over twenty-five years of experience in investments, corporate strategy and corporate governance. Mr. Mandel’s career includes serving as Chief Operating Officer at The Corporate Library (now GMI Ratings) where he designed and developed corporate governance best practices; serving as Chief Financial Officer of Circle.com (NASDAQ:CIRC); and serving as Executive Vice President, Finance and Development, Snyder Communications, Inc. (NYSE:SNC). Mr. Mandel served as Vice President in the Investment Research department at Goldman Sachs & Co. where he spent almost a decade advising institutional investors. Mr. Mandel previously served as a member of the Board of Directors, and on the audit committees, of Comsys IT Partners, Inc. (NASDAQ: CITP), Broadpoint Gleacher Securities Group, Inc. (now Gleacher and Co., Inc., NASDAQ: GLCH), and XLHealth Corp (now a United Healthcare company). Mr. Mandel also served on the Board of Directors of the Children’s National Medical Center in Washington, DC. Mr. Mandel holds an MBA in Finance from the Wharton School of Business at the University of Pennsylvania and an A.B. in Computer Science from Harvard University, and is a Chartered Financial Analyst (CFA) charter holder.

Jeffrey S. Stein has been a director since May 1, 2013. Mr. Stein is Co-Founder and Managing Partner of Power Capital Partners LLC, a private equity firm founded in 2011. Mr. Stein is an investment professional with over 20 years of experience in the high yield, distressed debt and special situations asset class who has substantial experience investing in the financial services industry. Previously Mr. Stein was Co-Founder and Principal of Durham Asset Management LLC, a global event-driven distressed debt and special situations asset management firm which had approximately $1.5 billion in total assets under management. From January 2003 through December 2009 Mr. Stein served as the

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Co-Director of Research at Durham responsible for the identification, evaluation and management of investments for the various Durham portfolios. From July 1997 to December 2002 Mr. Stein was a Director at The Delaware Bay Company, Inc., a boutique research and investment banking firm focused on the distressed debt and special situations asset class. From September 1991 to August 1995 Mr. Stein was an Associate at Shearson Lehman Brothers in the Capital Preservation & Restructuring Group. Mr. Stein currently serves as a director on the Boards of Dynegy Inc. (NYSE: DYN), Granite Ridge Holdings, LLC, and US Power Generating Company. Mr. Stein previously served as a director on the Board of KGen Power Corporation. Mr. Stein received a B.A. in Economics from Brandeis University and an M.B.A. with Honors in Finance and Accounting from New York University.

Nader Tavakoli has been Co-Chair and a Director since May 1, 2013. Mr. Tavakoli is Chairman and Chief Executive Officer of EagleRock Capital Management, a private investment partnership based in New York City. Prior to founding EagleRock in 2002, Mr. Tavakoli managed substantial investment portfolios with Odyssey Partners, a New York based private investment partnership. During his nearly 25 year investment career, Mr. Tavakoli has made substantial investments across numerous industries, including significant investments in financial services companies. Mr. Tavakoli began his professional career as an attorney with the New York City law firm of Milbank, Tweed, Hadley and McCloy, where he primarily represented institutional clients in banking, litigation and corporate restructuring matters. Mr. Tavakoli is a director of Magnachip Semiconductor Corp., a Korean based manufacturer of analogue and mixed signal semiconductors (NYSE: MX). Mr. Tavakoli serves on Magnachip’s audit and compensation committees. Mr. Tavakoli also serves on the board of MF Global Holdings Ltd., formerly engaged in securities brokerage, trading and clearance. Until its recent sale to AT&T, Mr. Tavakoli was a director of Nextwave Wireless Inc., a provider of broadband spectrum. Mr. Tavakoli is a Governance Leadership Fellow of the National Association of Corporate Directors. Mr. Tavakoli is the immediate past Chair of the Montclair State University Foundation Board and currently chairs that board’s investment committee. In addition, Mr. Tavakoli is actively involved with a number of other not-for-profit and philanthropic organizations. Mr. Tavakoli holds a B.A. in History from Montclair State University, where he was selected Valedictorian, and a Juris Doctor from the Rutgers Law School, where he was an editor of the Rutgers Law Review

Board Leadership Structure

The Board does not have a policy on whether or not the roles of Chief Executive Officer and Board Chair should be separate and, if they are to be separate, whether the Chair should be selected from the non-employee Directors, an employee or an outsider. The Board believes that it should be free to make this choice any way that it deems best for Ambac at any given point in time. While the Board has no fixed policy with respect to combining or separating the offices of Board Chair and Chief Executive Officer, those two positions have been held by separate individuals for the last several years, with the position of Co-Chairs of the Board currently being filled by Victor Mandel and Nader Tavakoli and the position of Chief Executive Officer by Diana N. Adams. The Company believes this is the appropriate leadership structure for it at this time.

Each of our directors, other than Ms. Adams, is independent (see “Director Independence” below), and the Board believes that the independent directors provide effective oversight of management.

Board Committees

The current members of each of the committees of the Board, as well as the current Chairman of each of the committees of the Board, are identified in the following paragraphs. Each of the standing committees operates under a written charter adopted by the Board. The Board has adopted a written charter for each of our standing committees which are available in the Corporate Governance section of our Investor Relations website: http://ir.ambac.com. A copy of the each charter is also available to stockholders free of charge on request to our Corporate Secretary, at corporatesecretary@ambac.com.

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Audit Committee

The Audit Committee is currently comprised of Messrs. Eugene M. Bullis (Chairman), Victor Mandel, Jeffrey S. Stein and Nader Tavakoli. The main function of our Audit Committee is to oversee our accounting and financial reporting processes. The Audit Committee’s responsibilities include:

Our Board has determined that each of the directors serving on our Audit Committee is independent within the meaning of the rules of the SEC and the Listing Rules of NASDAQ. The Board of Directors has determined that, based on each member’s professional qualifications and experience, each of the members of the Audit Committee qualifies as an audit committee financial expert as defined under the rules of the SEC. Following the Effective Date and as of October 31, 2013, the Audit Committee met 3 times.

Compensation Committee

The Compensation Committee is currently comprised of Messrs. Eugene M. Bullis, Victor Mandel, Jeffrey S. Stein and Nader Tavakoli (Chairman). The purpose of our Compensation Committee is to assist the Board in overseeing our compensation programs. The Compensation Committee’s responsibilities include:

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Each member of our Compensation Committee is an “outside” director as defined in Section 162(m) of the Internal Revenue Code of 1986, as amended, and a “non-employee” director within the meaning of Rule 16b-3 of the Exchange Act. Our Board of Directors has determined that each of the directors serving on our Compensation Committee is independent as defined in the Listing Rules of NASDAQ. Following the Effective Date and as of October 31, 2013, the Compensation Committee met 6 times.

Governance and Nominating Committee

The Governance and Nominating Committee is currently comprised of Messrs. Victor Mandel (Chairman), Jeffrey S. Stein and Nader Tavakoli. Our Governance and Nominating Committee’s purpose is to assist our Board of Directors in identifying individuals qualified to become members of our Board of Directors consistent with criteria set by our Board of Directors, to oversee the evaluation of the Board of Directors and management, and to develop and update our corporate governance principles. The Governance and Nominating Committee’s responsibilities include:

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Each member of the Committee is a non-employee member of our Board of Directors. Our Board of Directors has determined that each of the directors serving on our Governance and Nominating Committee is independent as defined in the Listing Rules of NASDAQ. Following the Effective Date and as of October 31, 2013, the Governance and Nominating Committee met 5 times.

Strategy and Risk Policy Committee

The Strategy and Risk Policy Committee is currently comprised of Messrs. Victor Mandel, Jeffrey S. Stein (Chairman) and Nader Tavakoli. The charter for the Strategy and Risk Policy Committee was adopted in May 2013. The Strategy and Risk Policy Committee’s responsibilities include:

Following the Effective Date and as of October 31, 2013, the Strategy and Risk Policy Committee met 2 times.

Board’s Role in Risk Oversight

Among other things, the Board is responsible for understanding the risks to which we are exposed, approving management’s strategy to manage these risks, establishing policies that monitor and manage defined risks and measuring management’s performance against the strategy.

Our management team is responsible for managing the risks to which Ambac is exposed and reports on such matters to the applicable Board committees.

The Audit Committee oversees the management of risks associated with the integrity of our financial statements and our compliance with legal and regulatory requirements. In addition, the Audit Committee discusses policies with respect to risk assessment and risk management, including major financial risk exposure and the steps management has taken to monitor and control such exposures. The Audit Committee reviews with management, internal auditors, and external auditors the accounting policies, the system of internal controls over financial reporting and the quality and appropriateness of disclosure and content in the financial statements and other external financial communications.

The Compensation Committee oversees the management of risks primarily associated with our ability to attract, motivate and retain quality talent, particularly executive talent, compensation structures that might lead to undue risk taking, and disclosure of our executive compensation philosophies, strategies and activities.

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The Governance and Nominating Committee oversees the management of risks primarily associated with our ability to attract, motivate and retain quality directors, our corporate governance programs and practices and our compliance therewith. Additionally, the Governance and Nominating Committee evaluates the performance of the Board, its committees and management annually and considers risk management effectiveness as part of their evaluation. The Governance and Nominating Committee also performs oversight of the business ethics and compliance program, and reviews compliance with our Code of Business Conduct.

The Strategy and Risk Policy Committee oversees the management of risks primarily with respect to strategic plans and initiatives, oversight of our capital structure, financing and treasury matters and oversight of management’s process for the identification, evaluation and mitigation of our financial and commercial-related risks.

The full Board also receives quarterly updates from Board committees, and the Board provides guidance to individual committee activities as appropriate.

Director Independence

The Governance and Nominating Committee annually reviews the relationships that each director has with Ambac. In conducting this review, the Committee considers all relevant facts and circumstances, including any consulting, legal, accounting, charitable and familial relationships and such other criteria as the Governance and Nominating Committee may determine from time to time. Following such annual review, the Committee reports its conclusions to the full Board, and only those directors whom the Board affirmatively determines to have no material relationship with Ambac and otherwise satisfy the criteria for director independence established by the committee are considered independent directors.

Based on the review and recommendation of the Governance and Nominating Committee, the Board has determined that each of the director nominees standing for election, except Diana N. Adams, our Chief Executive Officer, has no relationship that, in the opinion of the Board of Directors, would interfere with the exercise of independent judgment in carrying out the responsibilities of a director and is an independent director as defined in the Listing Rules of NASDAQ. In determining the independence of our directors, the Board of Directors has adopted independence standards specified by applicable laws and regulations of the SEC and the Listing Rules of NASDAQ.