AMBAC FINANCIAL GROUP INC

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

PROXY STATEMENT PURSUANT TO SECTION 14(A) OF

THE SECURITIES EXCHANGE ACT OF 1934

(AMENDMENT NO. ____)

Filed by the Registrantx Filed by a Party other than the Registrant¨

AMBAC FINANCIAL GROUP, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

2025 NOTICE OF ANNUAL

MEETING OF STOCKHOLDERS &

PROXY STATEMENT

Ambac Financial Group, Inc.One World Trade CenterNew York, NY 10007Tel: 212.658.7470

AMBAC FINANCIAL GROUP, INC.

NOTICE OF THE 2025 ANNUAL MEETING OF STOCKHOLDERS

• Stockholders can participate from any geographic location with Internet connectivity. We believe this format allows for maximum stockholder participation. Stockholders may view a live audio webcast of the Annual Meeting and submit questions digitally during the meeting at www.virtualshareholdermeeting.com/AMBC2025. Please refer to the General Information - participating in the Annual Meeting section of the Proxy Statement for more details.

This notice of Annual Meeting and Proxy Statement and form of proxy are being distributed and made available on or about April 11, 2025.

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PROXY STATEMENT SUMMARY

Below are the highlights of important information you will find in this Proxy Statement for Ambac Financial Group, Inc. ("Ambac" or the "Company") and its subsidiaries. As it is only a summary, please review the complete Proxy Statement before you vote.

Ambac Financial Group Fiscal Year 2024 Highlights

Performance Highlights:

The following events summarize our performance highlights for fiscal year 2024:

1 Cirrata EBITDA margin performance measure represents EBITDA as a percentage of net commissions.

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Performance Against Compensation Metrics

Performance Against 2024 Short Term Incentive Plan Metrics. For the 2024 fiscal year, we established the following goals for each of our Short Term Incentive Plan ("STIP") financial performance metrics and assigned weighting factors as follows:

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(1)Reductions in Net Par Outstanding as of December 31, 2024 under the STIP were measured against Net Par Outstanding as of January 1, 2024; however, the Compensation Committee exercised its discretion by taking into consideration that the agreement related to sale of Ambac Assurance Corporation ("AAC") limited management's ability to reduce net par outstanding pending the close. See the Compensation Discussion & Analysis, page 48, for additional discussion of how the Committee considered performance against the Net Par Outstanding metrics.

(2)Gross Operating Run Rate Expenses is measured by comparing actual gross operating run rate expenses for the fourth quarter of a fiscal year to performance goals established against budgeted amounts.

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Performance against 2021 - 2023 LTIP metrics. In 2021, the Compensation Committee establishedthe Long Term Incentive Plan ("LTIP") performance metrics to align management's goals with certain key drivers of shareholder value: risk reduction, and managing the event driven nature of Ambac's business. Performance stock unit ("PSU") awards granted in 2021 were measured based on performance with respect to (i) reductions in Watch List and Adversely Classified Credits ("WLACC") weighted at 75% at AACand (ii) achieving certain EBITDA goals at Xchange Benefits weighted at 25%. While the payout of PSUs granted in 2021 would not settle for a three year period and be subject to the relative Total Shareholder Return ("rTSR") modifier, the measurement period for determining the achievement of goals against the pre-set metrics was set at two years (based on stockholder feedback, this performance measurement period was changed from two years to three years in all subsequent periods). All Ambac LTIP awards for our executive officers are paid in Ambac common stock at the end of a settlement period.

(1) Linear interpolation between levels results in a proportionate amount of the Ambac LTIP Target Award becoming earned and vested.

The 2021 PSU awards paid out in early 2024, following the end of a three year settlement period at December 31, 2023. The following graph/charts shows the Company's actual performance over the two year measurement period running from January 1, 2021 through December 31, 2022, compared to the achievement levels set forth in the chart above.

In addition, the final 2021 LTIP performance stock unit award payout at the end of a three year settlement period was reduced as a result of the impact of the rTSR modifier which serves as an additional metric with respect to performance based LTIP award payouts. Watchlist & Adversely Classified Credit net par outstanding at AAC was reduced to $8.3 billion during the performance period and was driven by active de-risking totaling $2.9 billion, including Mets Queens ballpark, Puerto Rico, and certain reinsurance transactions. The Xchange EBITDA, based on 80% of the total Xchange EBITDA, at the end of the

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performance period was $12.9 million, which was $0.8 million below original projections with higher than projected expenses for both personnel and compliance costs. Ambac's rTSR lagged against our peers and resulted in a total shareholder return over the three year performance period of -5.2% and a ranking of 10 out of the 12 peer participants. As a result, after applying Ambac's rTSR modifier the LTIP performance multiple was reduced by 10%.

Response to 2024 Say on Pay Vote and Stockholder Outreach

At our 2024 annual meeting, our Say on Pay proposal received support from stockholders representing approximately 95% of the votes actually cast on this proposal, either in person or by proxy, at the meeting. We greatly appreciate the affirmative support of our stockholders with regard to our executive compensation program.

Key Features of Our Executive Compensation Program

Overall, our current executive compensation program heavily emphasizes performance and equity-based compensation to closely align management's incentives with stockholder interests, and includes other practices that we believe serve stockholder interests such as maintaining an executive stock ownership and retention policy, not providing tax “gross-up” payments, providing limited perquisites, maintaining a recoupment policy for incentive-based compensation and maintaining policies prohibiting the hedging or pledging our Company’s stock.

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CORPORATE SOCIAL RESPONSIBILITY AND SUSTAINABILITY

Ambac is committed to being a good corporate citizen and communicating our social responsibility efforts. Our Board of Directors, senior management team, and employees understand social responsibility is integral to our business operations and a means by which we can deliver greater value to our stakeholders. To that end, in 2024 Ambac published its second amended and updated Corporate Social Responsibility Report, which highlights our corporate culture and attention to sustainability factors in our everyday decision-making and long-term strategy. See the "Sustainability" section of Ambac's website, at https://ambac.com/sustainability/default.aspx.

Ambac's long-term success depends not only on how we execute against our strategic priorities but also how we manage our relationships with our stakeholders, the communities in which we work and our employees. For this reason, we take an integrated approach to sustained value creation and managing risk in and around our business. In 2024, Ambac updated its responses to the Global Reporting Initiative ("GRI") voluntary reporting framework and, with respect to certain investments, the "key performance indicators" promulgated by the Sustainability Accounting Standards Board ("SASB"). See the "Sustainability" section of Ambac's website, athttps://ambac.com/sustainability/default.aspx to review our GRI Content Index and SASB Content Index.

Business Model

Ambac Financial Group, Inc. operates two principal businesses:

•Insurance Distribution —Ambac's specialty property and casualty ("P&C") insurance distribution business includes Managing General Agents, Underwriters and other appointed and delegated underwriting businesses (collectively "MGAs" or "MGA/Us"), an insurance broker, and other distribution and underwriting businesses. Insurance Distribution includes Beat Capital Partners Limited, which was acquired on July 31, 2024. At December 31, 2024, Ambac's insurance distribution platform operates in the following lines of business: accident & health, specialty auto, other professional, marine & energy, niche specialty risks, property, reinsurance, professional director's & officers ("D&O") and other specialty lines.

•Specialty Property and Casualty Insurance — Ambac's Specialty Property & Casualty Insurance program business currently includes five carriers (collectively, “Everspan”). Everspan carriers have an A.M. Best rating of 'A-' (Excellent) which was affirmed on June 13, 2024.

Ambac has entered into an agreement to sell Ambac Assurance Corporation and its wholly owned subsidiaries, including Ambac Assurance UK Limited (“Ambac UK” or "AUK") and Ambac Financial Services LLC, pursuant to the stock purchase agreement, dated June 4, 2024 (the "Purchase Agreement"), with American Acorn Corporation ("Buyer"), a Delaware corporation owned by funds managed by Oaktree Capital Management, L.P. The assets and liabilities of AAC and its subsidiaries (collectively "the Discontinued Operation") that will be transferred in the sale are classified as held-for-sale, and their results presented as discontinued operations. Refer to Note 5. Discontinued Operation to the Consolidated Financial Statements included in Item 8 of Ambac's Annual Report on Form 10-K for the year ended December 31, 2024, for further information about the sale of AAC.

Our corporate initiatives are governed by our corporate Mission, Vision and Values.

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Corporate Governance

Our Board conducts an annual review of its governance practices, committee charters and governance policies to ensure that the Company’s practices are in line with current leading practices. We are committed to a corporate governance approach that aligns the interests of management, the Board of Directors and our stockholders. In furtherance of this approach, in the Fall of 2024 our investor relations department reached out to stockholders representing approximately 48% of our outstanding common stock to offer a meeting with the Chairman of the Board and our Chief Executive Officer. The purpose of the meetings was to solicit feedback from our stockholders on the AAC strategic plan and the sale to certain funds managed by Oaktree Capital Management. Our Chief Executive Officer provided a brief business update and participated in a discussion regarding the transaction, strategies and go-forward business plan. We received positive feedback our efforts and progress in advancing our strategic initiatives.

Consistent with our Board's proactive efforts in soliciting and responding to stockholder feedback and, following the recommendations of the Governance and Nominating Committee and the Compensation Committee, over the past several years we've implemented the following changes relating to ourcorporate governance practices andcompensation program in an effort to advance best practices and be responsive to stockholders:

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Our current slate of continuing directors is comprised of individuals with diverse skill sets which are necessary in light of the unique nature of Ambac’s business. Four of our director nominees self-identify as men, three self-identify as women, and one director nominee self-identifies as Hispanic.

Sustainability

In 2021, an internal management committee was established to focus on enhancement of relevant policies, procedures and disclosures to reflect Ambac’s approach to sustainability issues. To ensure that this is appropriately managed and communicated throughout the organization, we have designed the following governance structure:

•Board of Directors: Primary oversight of sustainability issues has been assigned to the Governance & Nominating Committee, which oversees strategy and public reporting.

•Executive Leadership Sponsors: Ambac's CEO, General Counsel and Chief Strategy Officer provide direction on sustainability strategy and public reporting.

•Management Committee: Senior leaders from Legal, Human Resources, Investor Relations, and Risk Management meet regularly to drive decision-making, accountability and ownership of reporting and policy initiatives.

•Employees: Ambac’s commitment to sustainability is firm-wide and includes input and participation from employees across the organization.

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Ambac published its second amended and updated Corporate Social Responsibility Report in 2024 and updated its responses to the GRI voluntary reporting framework and, with respect to certain investments, the "key performance indicators" promulgated by SASB." See the "Sustainability"section of Ambac's website.

Climate Change Risk

The Company considers climate risk as it may impact the exposures we insure and the investments we make. As such, the Company’s climate risk is monitored by its Enterprise Risk Management Committee for the primary purposes of both assessing the potential impact of climate change on the Company’s business operations and overseeing the implementation of controls to mitigate this risk to acceptable levels. Currently, climate change risk is not deemed a material risk to Ambac and, as the business continues to transform, climate change risk materiality will be monitored through its Enterprise Risk Management process, which takes input from various business units.

Data Security and Privacy

Ambac relies on digital technology to conduct its businesses and interact with internal and external parties. With this reliance on technology comes associated security risks. Wemaintain an information security program that is designed to protect and preserve the confidentiality, integrity and availability of information located on our systems.

Risk awareness is an important componentof Ambac’s cybersecurity program. We require cybersecurity awareness training for all of our employeesat the time of onboarding and on an annual basis. The training isdesigned to educate employees about cyber risk and help them identify and avoid potential threats. We also regularly test employee awareness through simulated phishing exercises. Ambac also engages third-party consultants to conduct penetration tests andperiodic risk assessments to identify any potential technical security vulnerabilities.

Given the ongoing proliferation ofcyber threats, we continue to mature our defense capabilities with enhanced monitoring of our computer systems for potential new threats. We also leverage the use of multi-factor authentication with the aim to provide an additional layer of defense against unauthorized access to our systems.

Ambac’s business operations also rely on the continuous availability of its computer systems. We maintain and test our business continuity plan and report results to senior management and our Board of Directors. The Board of Directors oversees the risk management process and engages with management on risk management issues, including cybersecurity risks.

We also maintain a cyber incident response plan that outlines the appropriate processes and procedures for incident management (including minimizing impact, investigating, and remediating root cause) and complying with applicable legal requirements (including timely and accurate reporting of any required cybersecurity or privacy incident).

Ambac and its subsidiaries are subject to numerous laws and regulations in a number of jurisdictions regarding its information systems, particularly with regard to certain personal information. We have implemented measures to prevent access to personal information on our system. Ambac's privacy policy is available on our website.

Workplace Culture

Ambac is committed to fostering, cultivating and preserving a culture of respect and teamwork. Our human capital is one of the most valuable assets we have. The collective sum of the individual differences, life experiences, knowledge, inventiveness, innovation, self-expression, unique capabilities and talent that our employees invest in their work represents a significant part of not only our culture, but our reputation and the company’s achievements as well.

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Training, Development and Well-Being of Employees

Developing employees professionally and personally strengthens the entire organization. Ambac is committed to the professional development and personal health of its employees through established policies and events which we believe have contributed to our low 6.5% voluntary turnover ratio.

•Ambac has a management development program that was instituted to identify certain rising employees to be appointed to a senior advisory team, the goal of which is to promote, retain, and incentivize talented individuals within the Company. Selected senior managers provide input and lead initiatives related to improving work environment/culture and corporate efficiencies, fostering better communication and team building.

•Professional development is encouraged for all employees with fee and tuition reimbursement.

•Ambac’s commitment to the health and safety of its employees was recognized by the International WELL Building Institute (IWBI) with the award of the WELL Health-Safety Rating following the successful completion of 15 core feature requirements in the following areas: Health Service Resources, Emergency Preparedness Programs, Air and Water Quality Management, Stakeholder Engagement and Communication, and Cleaning and Sanitation Procedures. The WELL Health-Safety Rating is an evidence based, third-party verified rating, focusing on operational policies, maintenance protocols, stakeholder engagement and emergency plans to address health and safety-related issues.

•Health and wellness training events are held regularly including financial wellness seminars.

Philanthropy

•Ambac supports many charities, both domestic and abroad and we have a paid time off employee volunteering program, promoting and providing opportunities for employees to volunteer for causes that benefit our communities.

•Since 2017 Ambac has supported, financially and via management board service, Self Help Africa, a leading international development charity, dedicated to ending hunger and poverty in rural Africa. Self Help Africa's work spans several areas across nine African countries including, among other things, agriculture and nutrition, micro finance, gender equality and climate change.

•For over 20 years, Ambac has supported, both financially and through volunteer work, The Children's Village. The Children’s Village was founded in 1851, and today, their mission remains to work in partnership with families to help society’s most vulnerable children so that they become educationally proficient, economically productive, and socially responsible members of their communities.

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AMBAC FINANCIAL GROUP, INC.

One World Trade Center

New York, New York 10007

PROXY STATEMENT

GENERAL INFORMATION

INFORMATION ABOUT THE ANNUAL MEETING AND VOTING

Proxy Materials

Why did I receive these Proxy Materials?

The Board of Directors of Ambac Financial Group, Inc. ("Ambac" or the "Company") 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 2025 Annual Meeting of Stockholders (the "Annual Meeting"), which will take place on May 28, 2025 at 11:00 a.m. (Eastern). The meeting will be conducted in a virtual format only. Stockholders can participate from any geographic location with Internet connectivity. We believe this format allows for maximum stockholder participation. Stockholders may view a live webcast of the Annual Meeting and submit questions digitally during the meeting at www.virtualshareholdermeeting.com/AMBC2025. Please refer to the Participating in the Annual Meeting section of the Proxy Statement for more details. As a stockholder, you are invited to participate in 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 2024 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 (collectively, “Proxy Materials”) include:

•Our Proxy Statement for the 2025 Annual Meeting of Stockholders;

•Our 2024 Annual Report to Stockholders, which includes our Annual Report on Form 10-K for the fiscal year ended December 31, 2024; and

•The proxy card or a voting instruction card for the Annual Meeting.

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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:

•View our Proxy Materials for the Annual Meeting on the internet and vote your shares; and

•Instruct us to send our future Proxy Materials to you electronically by email.

Our Proxy Materials are available atwww.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 Proxy Materials or Internet Notice. Stockholders who do not receive a separate copy of our Proxy Materials or Internet Notice and want to receive a separate copy may request to receive a separate copy of, or additional copies of, our Proxy Materials or Internet Notice via the internet, phone or email, as outlined above. Upon such request we shall furnish such copy, or additional copies, promptly. Stockholders who share an address and receive multiple copies of our Proxy Materials or Internet Notice may also request to receive a single copy by writing to our Investor Relations Department, Ambac Financial Group, Inc., One World Trade Center, New York, New York 10007.

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:

• The election of seven directors named in this proxy statement to our Board of Directors.

•To approve, on an advisory basis, the compensation of our named executive officers.

• The ratification of the appointment of KPMG LLP as Ambac’s independent registered public accounting firm for the fiscal year ending December 31, 2025.

•To vote, on an advisory basis, on the frequency of future advisory votes to approve executive compensation

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

How does the Board of Directors recommend that I vote?

Our Board of Directors recommends that you vote your shares:

ü "FOR” each of its nominees to the Board of Directors.

ü "FOR” the approval, on an advisory basis, of the compensation of our named executive officers.

ü "FOR” the ratification of the appointment of KPMG LLP as our independent registered public accounting firm for the 2025 fiscal year.

ü In favor of "EVERY YEAR" holding an advisory vote to approve executive compensation.

Other than the four 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 William J. White, or either of them, will have the discretion to vote your shares on any additional matters properly presented for a vote at the Annual Meeting.

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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 2025 Annual Meeting of Stockholders is entitled to be voted with respect to all items on which stockholders may vote 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 51,091,190 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 of common stock are restricted. A 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 our 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 relevant Insurance Commissioners of the states of domicile of the insurance companies controlled by Ambac. 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 a transfer of shares (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 (including a group of persons treated as a five-percent stockholder) shall be increased.

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 Inc., you are considered, with respect to those shares, thestockholder 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 thebeneficial owner of shares held instreet 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 in person at the Annual Meeting or by proxy. Even if you plan to participate in the virtual 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 participate in the virtual Annual Meeting. 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.

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 participating in the virtual 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. If you hold shares through a bank or broker, please refer to your proxy card or other information forwarded by your bank or broker to see which voting options are available to you.

•You may submit your proxy by using the internet. The address of the website for submitting your proxy via the Internet is www.proxyvote.com for both registered holders and beneficial owners of our common stock holding in street name. Internet proxy submission is available 24 hours a day and will be accessible until 11:59 p.m. Eastern Time on May 27, 2025. Easy-to-follow instructions allow you to submit your proxy and confirm that your instructions have been properly recorded.

•You may submit your proxy by calling. The phone number for submitting your proxy by phone is 1-800-690-6903. Submitting your proxy by phone is available 24 hours a day and will be accessible until 11:59 p.m. Eastern Time on

May 27, 2025.

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•You may submit your proxy by mail. As a result of implementing “Notice and Access,” you may request to receive printed copies of Proxy Materials by mail or electronically by email by following the instructions provided in the Internet Notice. You may submit your request in writing to our Corporate Secretary at Ambac Financial Group, Inc., One World Trade Center, New York, New York 10007 (or you can send an email to corporatesecretary@ambac.com). Once you receive your Proxy Materials, simply mark your proxy card, date and sign it, and return it in the postage-paid envelope.

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 (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 World Trade Center, New York, New York 10007 (and you can send a copy via email to corporatesecretary@ambac.com), prior to your shares being voted, or (iii) participating in the virtual Annual Meeting and casting a vote. Participation in the meeting will not cause your previously granted proxy to be revoked unless you specifically so request or cast a vote at the virtual 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 to parties other than Ambac, except:

•As necessary to meet applicable legal requirements;

•To allow for the tabulation and certification of votes; or

•To facilitate a proxy solicitation.

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

The presence, in person or by proxy, of the holders of a majority of the voting power of Ambac’s shares of common stock outstanding as of the Record Date will constitute a quorum. Both abstentions and broker non-votes (described below) are counted for the purpose of determining the presence of a quorum.

How may I vote in the election of directors, and how many votes must the nominees receive to be elected?

With respect to the election of directors, you may:

•vote “FOR" each of the seven nominees for director;

•vote “AGAINST” each of the seven nominees for director; or

•“ABSTAIN” from voting on each of the seven nominees for director.

Our directors are elected by a majority of votes cast unless the election is contested, in which case directors are elected by a plurality of votes cast. A majority of votes cast means that the number of shares voted “FOR” a director exceeds the number of votes cast “AGAINST” a director; abstentions are not counted as votes cast either “FOR” or “AGAINST." If an incumbent director in an uncontested election does not receive a majority of votes cast FOR such incumbent’s election, the director is required to submit a letter of resignation to the Board of Directors for consideration by the Governance and Nominating Committee. The Governance and Nominating Committee is required to promptly assess the appropriateness of such nominee continuing to serve as a director and recommend to the Board the action to be taken with respect to the tendered resignation. The Board is required to determine whether to accept or reject the resignation, or what other action should be taken, within 90 days of the date of the certification of election results. Each holder of our common stock is entitled to one vote for each share held as of the Record Date. There are no cumulative voting rights associated with any of Ambac's common stock.

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How may I vote for the non-binding advisory resolution regarding executive compensation, and how many votes must this proposal receive to pass?

•vote “FOR” the approval of the non-binding resolution regarding executive compensation;

•vote “AGAINST” the approval of the non-binding resolution regarding executive compensation; or

•"ABSTAIN” from voting on the proposal.

In accordance with applicable law, this vote is “advisory,” meaning it will serve as a recommendation to our Board of Directors, but will not be binding. However, our Board of Directors and the Compensation Committee thereof will consider the outcome of the vote when making future compensation decisions for our executive officers.

How may I vote for the proposal to ratify the appointment of our independent registered public accounting firm, and how many votes must this proposal receive to pass?

•vote “FOR” the ratification of the accounting firm;

•vote “AGAINST” the ratification of the accounting firm; or

•“ABSTAIN” from voting on the proposal.

In order to pass, the number of votes cast FOR this proposal must exceed the number votes cast AGAINST this proposal by holders of our common stock who are present in person, or represented by proxy at the Annual Meeting and entitled to vote on this matter. Abstentions are not counted as either votes cast “FOR” or “AGAINST” this proposal.

How may I vote for the non-binding advisory resolution regarding the frequency of future advisory votes to approve executive compensation, and how many votes must this proposal receive to pass?

•vote to hold an advisory vote on executive compensation "EVERY YEAR;"

•vote to hold an advisory vote on executive compensation "EVERY 2 YEARS;" or

•vote to hold an advisory vote on executive compensation "EVERY 3 YEARS."

In accordance with applicable law, this vote is “advisory,” meaning it will serve as a recommendation to our Board of Directors, but will not be binding. However, our Board of Directors and the Governance and Nominating Committee thereof will consider the outcome of the vote when making future decisions about the frequency of future advisory votes to approve executive compensation.

What are broker non-votes, and how are broker non-votes and abstentions counted when tabulating votes?

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, 2025. In tabulating the voting result for any “non-routine” 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 “non-routine” matter being voted on at the Annual Meeting, assuming that a quorum is obtained. Likewise, abstentions are not counted as either votes cast “FOR” or “AGAINST” and will not affect the outcome of any matter being voted on at the Annual Meeting. We do not expect there to be any broker non-votes with respect to the proposal to ratify the appointment of KPMG LLP as Ambac’s independent registered public accounting firm for the fiscal year ending December 31, 2025 because the proposal is considered “routine.”

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Brokers may not 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.

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

Ambac pays the entire cost of preparing, assembling, printing, mailing, and distributing the 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 choose 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. In addition, Ambachas engaged D.F. King & Co., Inc. (“D.F. King”) to assist in the proxy solicitation process. D.F. King will be paid a fee of approximately $15,000, plus additional fees for additional services at D.F. King’s reasonable and customary rates, plus reimbursements for costs and expenses incurred by D.F. King.

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

Other than the four 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 William J. White, will have the discretion to vote your shares on any additional matters properly presented for a vote at the Annual Meeting. If for any reason, any of the nominees for director included in this Proxy Statement 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 following the date on which the Annual Meeting concludes.

Participating in the Annual Meeting

How can I participate in the Annual Meeting?

We are conducting a virtual Annual Meeting so our stockholders can participate from any geographic location with Internet connectivity. Participation opportunities are reasonably comparable to those provided at in-person meetings.We have structured our virtual meeting to provide stockholders the same rights as if the meeting were held in person, including the ability to vote shares electronically during the meeting and ask questions in accordance with the rules of conduct for the meeting.

•To participate in the Annual Meeting, including to vote at the meeting, you must access the meeting website at www.virtualshareholdermeeting.com/AMBC2025 and enter the 16-digit control number found on the Notice of Internet Availability of Proxy Materials or on the proxy card or voting instruction form provided to you with this Proxy Statement.

•Whether or not you plan to participate in the virtual Annual Meeting, it is important that your shares be represented and voted. We encourage you to access www.proxyvote.com or call 1-800-690-6903 and vote in advance of the Annual Meeting.

•Stockholders are able to submit questions for the Annual Meeting’s question and answer session during the meeting through www.virtualshareholdermeeting.com/AMBC2025. We will respond as practical to questions during the meeting. Additional information regarding the rules and procedures for participating in the Annual Meeting will be set forth in our meeting rules of conduct, which stockholders can view during the meeting at the meeting website or during the ten days prior to the meeting at www.proxyvote.com.

•We encourage you to access the Annual Meeting before it begins. Online check-in will be available at www.virtualshareholdermeeting.com/AMBC2025 approximately 15 minutes before the meeting starts on May 28, 2025. If you have difficulty accessing the meeting, please call the support lines available on the meeting platform. We will have technicians available to assist you.

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Do directors attend the Annual Meeting?

It is currently expected that all of our continuing directors will participate in the virtual Annual Meeting of Stockholders. All seven of our directors who were on the Board last year participated in the virtual 2024 Annual Meeting of Stockholders.

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

A complete list of stockholders of record entitled to vote at the Annual Meeting will be available for inspection by stockholders of record for a period of at least ten days before the Annual Meeting during ordinary business hours at our principal executive offices at One World Trade Center, New York, New York 10007.

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.

How can I contact Ambac’s transfer agent?

Contact our transfer agent by either writing to Computershare Inc., PO Box 505000, Louisville, KY 40233, or 462 South 4th Street, Suite 1600, Louisville, KY 40202, by telephoning 1-800-662-7232 or via the web atwww.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 William J. White, Corporate Secretary, at (212) 658-7456 or by email at corporatesecretary@ambac.com. If you have any questions about your investment in Ambac common stock, please contact Ambac's Investor Relations department at (212) 208-3177 or by email at ir@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 World Trade Center, New York, New York 10007 or by sending an email 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 to our Board. 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 our 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?

For Stockholder Proposals that are to be included in our Proxy Statement under Rule 14a-8. Pursuant to Rule 14a-8 under the Securities Exchange Act of 1934, as amended (“Exchange Act”), if a stockholder wants Ambac to include a proposal in our proxy statement and form of proxy for presentation at our 2026 Annual Meeting of Stockholders (other than a proposal relating to the nomination of a specific individual for election to our Board of Directors), the proposal must be received by us at our principal executive offices at One World Trade Center, New York, New York 10007, not later than December 12, 2025. The proposal must be sent to the attention of our Corporate Secretary, and must comply with the requirements of Regulation 14A under the Exchange Act (including, but not limited to, Rule 14a-8 or its successor provision).

Other Proposals and Nominations. Our by-laws govern the submission of nominations for director or other business proposals that a stockholder wishes to have considered at a meeting of stockholders, but which are not included in our proxy statement for that meeting. Under our by-laws, nominations for director or other business proposals to be addressed at our next annual meeting in 2025 may be made by a stockholder entitled to vote who has delivered a notice to the Corporate Secretary of Ambac Financial Group, Inc. no earlier than the close of business on February 27, 2026, and not later than March 27, 2026, except if the date of our next annual meeting is not within 30 days before or after the anniversary of our 2025 Annual Meeting of Stockholders, such notice must be delivered no earlier than the 90 th day before our 2026 Annual Meeting of Stockholders and no later than the later of the 60 th day before our 2026 Annual Meeting of Stockholders and the

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15 th day following the day on which public announcement of the date of our 2026 Annual Meeting of Stockholders is first made by the Company. The notice must set forth and describe the information required by Article II of our by-laws.

These advance notice and information requirements are in addition to, and separate from, the requirements that a stockholder must meet in order to have a proposal included in our proxy statement under the rules of the SEC. A proxy granted by a stockholder will give discretionary authority to the proxies to vote on any matters introduced pursuant to the above-referenced by-law provisions, subject to applicable rules of the SEC.

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 Exchange Act, the sections of this Proxy Statement entitled “Report of the Audit Committee” (to the extent permitted by the rules of the 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

Board of Directors

The Board oversees the business of Ambac and monitors the performance of management. Addressing the issues and the challenges associated with our legacy financial guarantee insurance business, as well as overseeing Ambac's new businesses in specialty property and casualty insurance and insurance distribution, requires a high level of focus, time commitment and engagement from our directors. The Board meets approximately five times per year in regularly scheduled meetings, but will meet more often, if necessary. The Board met eighteen times in 2024. Outside of formal meetings, directors frequently engage with management concerning Ambac’s business and strategies. In 2024, each director attended at least 97% of the total number of meetings of the Board and any committees on which he or she served. All of our current directors also serve as directors of AAC, which involves different work streams and considerations than their directorships at AFG.

Directors

The names of our continuing directors, and their ages, positions, and biographies as of the date of this proxy statement are set forth below. There are no family relationships among any of our directors or executive officers.

Our current slate of continuing directors and director nominees is currently comprised of individuals with diverse skill sets, which are necessary in light of the unique nature of Ambac’s business. Three of our director nominees self-identify as women; four of our director nominees self-identify as men; and one of our director nominees self-identifies as Hispanic.

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Ian D. Haft

Mr. Haft has been a director since March 28, 2016. In 2024, he was appointed Chief Financial Officer of ZATV Inc., after it acquired Electric Monster Media, Inc, where Mr. Haft had served as Chief Financial Officer and a member of the board of directors since 2021. Both companies operate in the digital media space. Mr. Haft is also Chief Executive Officer of Surgis Capital LLC, an investment manager and consulting firm he founded in 2018. From 2009 until 2017, Mr. Haft was a founding partner and Vice President and Secretary of Cornwall Capital Management LP (“Cornwall”), an investment manager. At Cornwall, Mr. Haft previously held the positions of Chief Financial Officer (until November 2011) and Chief Operating Officer and Chief Compliance Officer (until the end of 2015). Mr. Haft was also a member of Cornwall GP, LLC, the general partner of Cornwall Master LP. Prior to joining Cornwall, Mr. Haft was a Principal at GenNx360 Capital Partners, a private equity fund, from 2008 to 2009. From 2002 to 2008, Mr. Haft was a Senior Associate and then Vice President (from 2004) at ACI Capital Co., LLC, where he focused on middle market leveraged buyouts and growth equity investments on behalf of two private equity funds. Mr. Haft began his career at The Boston Consulting Group in 1993 and was also employed by Merrill Lynch & Co. and The Blackstone Group prior to joining ACI Capital in 2002. Mr. Haft served as member of the board of directors of Keweenaw Land Association from 2018 until 2021. Mr. Haft graduated magna cum laude with a BA in economics and mathematics from Dartmouth College in 1993 and he received his JD and MBA from Columbia University in 2000. Mr. Haft has extensive experience working with companies of all sizes and identifying, understanding and utilizing areas of value creation.

Mr. Haft has over twenty years of experience working in alternative asset management, investment banking and management consulting and has served on the boards of three public companies and nine private companies. Through this experience, he has developed strong capabilities in business strategy, strategic analysis of industries and companies, mergers and acquisitions, valuation, debt and equity financing, derivatives and hedging, financial controls and regulatory compliance. Mr. Haft’s background and experience make him well-qualified to serve on our Board of Directors and its Strategy Committee, and to chair the Audit Committee.

Lisa G. Iglesias

Ms. Iglesias has been a director since August 4, 2021. She is currently the Executive Vice President, General Counsel of Unum Group, an insurance company, a position she has held since January 2015. As the General Counsel of Unum Group, Ms. Iglesias has overall responsibility for the legal affairs of Unum, and heads a team of lawyers handling transactions, finance and investments, SEC reporting, corporate governance, regulatory matters and relationships, compliance and complex litigation. She also oversees Unum Group’s Internal Audit, Aviation and Information Security functions. Prior to joining Unum Group, Ms. Iglesias served as Senior Vice President, General Counsel and Secretary of WellCare Health Plans, Inc., a managed care company, from February 2012 to December 2014, having first joined WellCare in February 2010 as Vice President, Securities and Assistant General Counsel. Prior to that, she served as General Counsel and Corporate Secretary for Nordstrom, Inc., a fashion specialty retailer, from 2007 to 2008, and as General Counsel and Secretary of Spherion Corporation, a recruiting and staffing company, from 1999 to 2007. Earlier in her career Ms. Iglesias was an SEC and Mergers & Acquisitions attorney with the law firm of Greenberg Traurig from 1994 to 1998 and a tax CPA with KPMG Peat Marwick from 1989 to 1991. Ms. Iglesias serves on the board of the Public Education Foundation of Chattanooga, Tennessee. Ms. Iglesias received her bachelor’s and master’s degrees in accounting from the University of South Florida, and her law degree from the University of Miami. Honors and awards include receiving the 2025 Legends in Law Award, and being named in Latino Leaders magazineas one of the Top Latinos in Corporate America in 2022 and 2020 and one of the Top Latino Lawyers in 2018. In 2014 Ms. Iglesias was named one of the Top Women Legal officers in Corporate Counsel magazine.

Ms. Iglesias has over twenty-five years of experiencein finance and investments, risk management, corporate governance, regulatory matters, compliance, privacy, government affairs and litigation. Ms. Iglesias’ legal, finance and risk management experience make her well-qualified to serve on our Board of Directors and its Audit Committee, and to chair the Governance and Nominating Committee.

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Joan Lamm-Tennant

Ms. Lamm-Tennant has been a director since March 1, 2018. She is the independent Chair of the Boards of Directors of Equitable Holdings, Inc. and AllianceBernstein Holdings L.P. Ms. Lamm-Tennant was the Founder of Blue Marble Microinsurance, and from January 2016 to June 2020 served as its Chief Executive Officer. Blue Marble Microinsurance is a corporation formed by a consortium of eight insurance entities for the purpose of developing service ventures enabling the insurers to enter the micro-insurance market. Previously, Ms. Lamm-Tennant was the Global Chief Economist and Risk Strategist of Guy Carpenter & Company, LLC, the reinsurance and risk advisory operating company of Marsh & McLennan Companies. Prior to joining Guy Carpenter in 2007, Ms. Lamm-Tennant was the founding President of General Reinsurance Capital Consultants. She was an Adjunct Professor at the Wharton School, University of Pennsylvania from September 2005 to May 2016 and held the Laurence and Susan Hirsch Chair in International Business. Ms. Lamm-Tennant was a tenured Professor at Villanova from September 1989 to May 2000 and was awarded the Thomas Labrecque Chair Professorship in Business in 1999. She currently serves on the Board of Equitable Holdings, Inc., AllianceBernstein Holdings L.P., and Element Fleet Management Corp. Ms. Lamm-Tennant is the Executive Expert on Resilience and Sustainability for the International Insurance Society and author / commentator on environment, social and governance matters. She holds a Ph.D. in Finance and Investments from the University of Texas, Austin; an M.B.A. in Finance from St. Mary's University, San Antonio, Texas and a B.B.A. with Honors in Accounting from St. Mary's University, San Antonio, Texas.

Ms. Lamm-Tennant has over forty years of finance, and risk management experience in the insurance industry. She served as a risk strategist for Marsh & McLennan and formalized the enterprise wide risk oversight function resulting in the appointment of a Chief Risk Officer and a dedicated Board Risk Committee. Her expertise in emerging market strategy, enterprise risk modeling, implementation of risk-based decision processes and high value strategies resulting in capital efficiencies and profitable growth make her well-qualified to serve on our Board of Directors and its Compensation Committee and Governance and Nominating Committee, and to chair the Strategy Committee.

Claude LeBlanc

Mr. LeBlanc is a director, President and Chief Executive Officer of Ambac. He has held these positions since joining Ambac in January 2017. In the last eight years, Mr. LeBlanc has led Ambac through a holistic transformation, winding down its legacy financial guarantee business and reshaping Ambac into a specialty property and casualty insurance platform. Previously, Mr. LeBlanc was the Chief Financial Officer and Chief Restructuring Officer of Syncora Holdings Ltd. from 2010 through 2016, and from 2006 to 2009 he held the position of Executive Vice President. During this period, Mr. LeBlanc led the successful global restructuring of Syncora. Prior to joining Syncora, Mr. LeBlanc served as Senior Vice President of Corporate Development and Strategy and as a member of the Executive Management Group for XL Capital Ltd. He began his career at PricewaterhouseCoopers, where he advised on mergers and acquisitions, corporate restructurings, and transaction advisory. Mr. LeBlanc holds a BA in Economics from York University, a BComm from the University of Windsor and an MBA from the Schulich School of Business. He is a Chartered Accountant and Certified Public Accountant. Mr. LeBlanc is a member of the Schulich School of Business Dean’s Global Council; the Dean’s Strategic Council; and the Tech MBA Advisory Council. He previously served on the Board of Maiden Holdings, Ltd. until May 2021.

Mr. LeBlanc has more than thirty years of experience in the financial services sector and during that period has held a number of executive leadership roles overseeing strategy, capital management, corporate development, and risk management. Mr. LeBlanc’s extensive property and casualty and financial guarantee insurance experience makes him a valued officer and member of our Board of Directors.

Kristi A. Matus

Ms. Matus has been a director since June 22, 2023. She is the Chair of the Board of Directors of Cerence, Inc. From October 2020 until July 2022, she was the Chief Financial Officer and Chief Operating Officer of Buckle Agency LLC, a digital financial services company which provides insurance products and solutions for the rapidly growing ride-share and delivery segment and is a strategic partner for MGAs. Ms. Matus was an Executive Advisor for Thomas H. Lee Partners L.P. from 2017 to 2020, advising the senior team within the healthcare IT portfolio on strategy, talent, and team integration prior to an acquisition. From 2014 to 2016, Ms. Matus served as Executive Vice President and Chief Financial & Administrative Officer of athenahealth, Inc. (“athenahealth”), a company partnering with healthcare organizations across the care continuum to drive clinical and financial results through technology, insight, and expertise. Prior to joining athenahealth, Ms. Matus served as

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Executive Vice President and Head of Government Services of Aetna, Inc. (“Aetna”) managing the Medicare, Medicaid, public and labor and Federal employee health plans. Prior to Aetna, she held several senior leadership roles at United Services Automobile Association (“USAA”), including Executive Vice President and Chief Financial Officer. She began her career at Thrivent, where she held various financial and operational roles for over a decade.

Ms. Matus has over thirty years of experience in finance, risk management and corporate governance in the insurance and technology industry. Ms. Matus’ leadership skills developed through her roles at Buckle, athenahealth, Aetna and USAA make her well-qualified to serve on our Board of Directors and to chair its Compensation Committee and serve on the Audit Committee.

Michael D. Price

Mr. Price has been a director since June 22, 2023. Mr. Price served as President and Chief Executive Officer of Platinum Underwriters Holdings, Ltd. from 2005 until its acquisition by RenaissanceRe Holdings Ltd in 2015. Platinum Underwriters Holdings provided property and casualty reinsurance coverages to insurance and select reinsurers worldwide. Prior to that, he served briefly as Platinum’s Chief Operating Officer, and was President of Platinum US from 2002 until 2005. Mr. Price was Chief Underwriting Officer of Platinum’s predecessor, the former reinsurance segment of The St. Paul Companies, Inc. Prior thereto, Mr. Price was Chief Operating Officer of Associated Aviation Underwriters Incorporated, a subsidiary of Global Aerospace Underwriting Managers Ltd., a leading global MGU of aviation insurance and risk management solutions. Earlier in his career, he held progressively senior roles within other companies in the property and casualty insurance industry. Mr. Price is a Fellow of the Casualty Actuarial Society and holds the Financial Risk Manager designation of the Global Association of Risk Professionals. Mr. Price was a member of the Board of Directors of The Hanover Insurance Group, Inc. from July 2017 until May 2020.

Mr. Price has over thirty-five years of experience in experience in finance and risk management in the insurance industry. Mr. Price’s C-Suite leadership experience as a Chief Executive Officer of a publicly traded company, as well as his knowledge of the insurance and reinsurance industries, make him well-qualified to serve on our Board of Directors and its Audit Committee, Compensation Committee and Strategy Committee.

Jeffrey S. Stein

Mr. Stein has been Chairman of the Board since January 1, 2015 and has served as a director since May 1, 2013. Mr. Stein is Founder and Managing Partner of Stein Advisors LLC, a financial advisory firm that provides consulting services to public and private companies and institutional investors. Mr. Stein provides the perspective of a successful investment professional with over thirty years of experience in both the debt and equity asset classes and has substantial experience investing in the financial services industry. Previously, Mr. Stein was a Co-Founder and Principal of Durham Asset Management LLC, a global event-driven distressed debt and special situations equity asset management firm. From January 2003 through December 2009, Mr. Stein served as 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 served as Co-Director of Research at The Delaware Bay Company, Inc., a boutique research and investment banking firm focused on the distressed debt and special situations equity asset classes. From September 1991 to August 1995, Mr. Stein was an Associate and Assistant Vice President at Shearson Lehman Brothers in the Capital Preservation & Restructuring Group. Mr. Stein previously served as a director on the Boards of Vertex Energy, Inc., Rite Aid Corporation, Troika Media Group, Inc., Aearo Technologies LLC, GWG Holdings, Inc., Intelsat Connect Finance S.A., NMC Health plc, Westmoreland Coal Company, and Dynegy Inc. and as a board observer on the Board of TORM plc. 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.

Mr. Stein is an accomplished corporate executive and director, including leadership and committee positions, of both public and private companies, who has substantial experience investing in the financial services industry. Mr. Stein has served as an Executive Chairman, Chief Executive Officer, Chief Restructuring Officer, and Liquidating Trustee and as a director on audit, compensation, corporate governance, finance, restructuring and risk committees (including as chairman of those committees). In his capacity as a corporate executive and director, Mr. Stein has specifically focused on capital allocation, operating and financial performance, capital structure optimization, asset acquisitions and dispositions, corporate strategy,

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risk management and investor communications. As a result, Mr. Stein has a wealth of knowledge with respect to the financial, institutional and risk management issues currently facing Ambac. His breadth of experience makes Mr. Stein well qualified to be Chairman of our Board, and to serve on the Governance and Nominating Committee.

Board Leadership Structure

The Company currently has a separate Chief Executive Officer and independent Board Chair. These two positions have been held by separate individuals for the last several years, with the position of Chair of the Board currently being filled by Mr. Stein and the position Chief Executive Officer by Mr. LeBlanc. The Board believes that this structure is appropriate for Ambac at this time because it encourages the free and open dialogue of competing views while providing for strong checks and balances. In addition, six out of seven of our directors are independent, and the Board believes that the independent directors provide effective oversight of management. See “Director Independence.” The Board has no fixed policy with respect to combining or separating the offices of Board Chair and Chief Executive Officer, and it believes it should be free to make this choice in the manner that it deems best for Ambac and its stockholders at any given point in time.

Board Committees

The current members of each of the committees of the Board, as well as the current Chair 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, which is available in the Corporate Governance section of our Investor Relations website: https://ambac.com/investor-relations/governance/governance-documents/default.aspx. A copy of each charter is also available to stockholders free of charge on request to our Corporate Secretary, at corporatesecretary@ambac.com.

Audit Committee

The Audit Committee is currently comprised of Messrs. Haft (Chairman) and Price and Mses. Iglesias and Matus. The main function of our Audit Committee is to oversee our accounting and financial reporting processes. The Audit Committee’s responsibilities include:

• Appointing, compensating, retaining, and overseeing the work performed by our independent registered public accounting firm's engagement.

• Approving the audit, non-audit and tax services to be performed by our independent registered public accounting firm.

• Evaluating the experience, performance, qualifications, and independence of our independent registered public accounting firm.

•Reviewing the activities and organizational structure of the internal audit function, as well as the qualifications of its personnel.

• Reviewing the integrity of our financial statements and our compliance with legal and regulatory requirements as they relate to financial statements or accounting matters.

• Reviewing with management the design, operation and effectiveness of our internal controls over financial reporting and our critical accounting policies.

• Reviewing with management our annual audited financial statements, quarterly financial statements, earnings releases and any other material press releases related to accounting or financial matters announcements.

•Reviewing with management our major financial risk exposures and the steps that management has taken to monitor and control such exposures.

• Reviewing and approving the Audit Committee report for inclusion in our annual proxy statement.

• Reviewing our Regulation FD Policy.

• Establishing procedures for the confidential and anonymous receipt, retention and treatment of complaints regarding accounting, internal accounting controls or auditing matters.

Our Board has determined that each of the directors serving on our Audit Committee is independent within the meaning of the Listing Rules of New York Stock Exchange ("NYSE"). The Board of Directors has determined that, based on each member’s professional qualifications and experience, each of the members of the Audit Committee are financially literate and that Messrs. Haft, and Price and Mses. Iglesias, and Matus qualify as "audit committee financial experts" as defined under the rules and regulations of the SEC. The Audit Committee regularly meets in executive session with both our independent

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registered public accounting firm, and internal audit, without Ambac management present. The Audit Committee metfive times in 2024.

Compensation Committee

The Compensation Committee is currently comprised of Mses. Lamm-Tennant and Matus (Chair) and Messrs. Haft and Price. The purpose of our Compensation Committee is to assist the Board in overseeing our compensation program. The Compensation Committee’s responsibilities include:

• Reviewing the overall compensation principles governing the compensation and benefits of our executive officers and other employees.

• Evaluating the performance of our Chief Executive Officer.

• Reviewing the procedures for the evaluation of our executive officers, other than our Chief Executive Officer.

• Reviewing and approving the selection of our peer companies to use as a reference in determining competitive compensation packages.

• Determining all executive officer compensation (including but not limited to salary, bonus, incentive compensation, equity awards, benefits and perquisites).

• Reviewing and approving the terms of any employment agreements and severance arrangements, change-in-control agreements, and any special or supplemental compensation and benefits for our executive officers and individuals who formerly served as executive officers.

• Acting as the administering committee for our stock and bonus plans and for any equity compensation arrangements that may be adopted by Ambac from time to time.

• Reviewing and discussing with management the annual Compensation Discussion and Analysis (CD&A) disclosure, and based on this review and discussion, making a recommendation to include the CD&A disclosure in our annual proxy statement.

• Preparing the annual Compensation Committee Report for inclusion in our annual proxy statement.

Each member of our Compensation Committee is 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 within the meaning of the Listing Rules of NYSE. The Compensation Committee met eleven times in 2024.

In 2024, the Compensation Committee directly engaged Meridian Compensation Partners, LLC, a nationally recognized independent compensation consulting firm ("Meridian"), to assist it with benchmarking and compensation analyses, as well as to provide information and advice on executive compensation practices and determinations, including information on award design for both our Short Term Incentive Plan (“STIP”) and Long Term Incentive Plan (“LTIP”).

Our Chief Executive Officer will attend meetings of the Compensation Committee (other than executive sessions) and express his view on the Company’s overall compensation philosophy. Following year-end, the Chief Executive Officer makes recommendations to the Compensation Committee as to the total compensation package (salary, and STIP and LTIP awards) to be paid to each of our executive officers.

Our Executive Vice President and Chief Strategy Officer serves as management’s main liaison with the Compensation Committee and assists the Compensation Committee Chair in setting the agenda and gathering the requested supporting material for each Compensation Committee meeting. Our Corporate Secretary serves as secretary to the Compensation Committee.

Governance and Nominating Committee

The Governance and Nominating Committee is currently comprised of Mses. Iglesias (Chair) and Lamm-Tennant and Mr. Stein. 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 based on 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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• Evaluating the composition, size, organization, and governance of our Board of Directors and its committees, determining future requirements, and making recommendations regarding future planning, the appointment of directors to our committees, and the selection of chairs of these committees.

• Periodically reviewing the standards for director independence and providing the Board with an assessment of which directors should be deemed independent.

• Determining the criteria for Board membership.

• Overseeing policies and practices relating to environmental, social, and governance matters relevant to the Company.

• Overseeing the process for the self-evaluation of the Board and its committees.

• Reviewing and recommending to our Board of Directors the compensation of our non-employee directors.

• Reviewing plans for the succession of our executive officers.

• Reviewing and approving related party transactions according to our Related Party Transaction Policy.

• Administering a procedure to consider stockholder recommendations for director nominees.

• Evaluating and recommending candidates for election or re-election to our Board of Directors, including nominees recommended by stockholders.

• Reviewing periodically Ambac’s Code of Business Conduct and Ethics and compliance therewith.

Our Board of Directors has determined that each of the directors serving on our Governance and Nominating Committee is independent within the meaning of the Listing Rules of NYSE. The Governance and Nominating Committee met five times in 2024.

Strategy Committee

The Strategy Committee is currently comprised of Ms. Lamm-Tennant (Chair) and Messrs. Haft and Price, and its responsibilities include:

•Reviewing and making recommendations to the Board regarding strategic plans and initiatives, including potential material investments in joint ventures, mergers, acquisitions and other business combinations.

•Reviewing, evaluating and making recommendations to the Board regarding solicited or unsolicited strategic transactions, opportunities and alternatives involving the Company or the interest of the Company in any direct or indirect subsidiary.

The Strategy Committee met six times in 2024.

Board’s Role in Risk Oversight

Among other things, the Board is responsible for understanding the risks to which Ambac is exposed, overseeing management's strategy to manage these 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 Board and to the relevant committees of the Board depending on the nature of the risk, as described below.

The Audit Committee oversees the management of risk associated with the integrity of our financial statements and our compliance with legal and regulatory requirements. In addition, the Audit Committee reviews policies and procedures 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, our internal auditors, and our independent registered public accounting firm Ambac's critical 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 risk primarily associated with (i) our ability to attract, motivate and retain high-quality and talented employees, particularly executives; and (ii) compensation structures that might lead to undue risk taking.

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The Governance and Nominating Committee oversees the management of risk primarily associated with our ability to attract, motivate and retain high-quality directors, our corporate governance and sustainability programs and practices and our compliance therewith. Additionally, the Governance and Nominating Committee establishes a framework for the Board and each of its committees to conduct an annual self-evaluation process and ensures that risk management effectiveness is a part of this evaluation. The Governance and Nominating Committee also performs oversight of the business ethics and compliance program by conducting an annual review and assessment of our Code of Business Conduct and Ethics.

The Strategy Committee oversees the management of risk and risk appetite primarily with respect to strategic plans and initiatives.

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 none of Messrs. Haft, Price or Stein, or Mses. Iglesias, Lamm-Tennant or Matus has a 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 each of them is an independent director as defined in the Listing Rules of NYSE. In determining the independence of our directors, the Board of Directors has adopted the independence standards specified by applicable laws and regulations of the SEC and the Listing Rules of NYSE.

Compensation Committee Interlocks and Insider Participation

None of the current members of the Compensation Committee has been an officer or employee of Ambac. In 2024, each of Messrs. Haft, Price, and Stein, and Mses. Lamm-Tennant and Matus served as members of the Compensation Committee. None of our executive officers serves on the board of directors or compensation committee of a company that has an executive officer that serves on our Board of Directors or the Compensation Committee.

Consideration of Director Nominees

Stockholder Recommendations and Nominees

The Governance and Nominating Committee considers properly submitted recommendations for candidates to the Board of Directors from stockholders. In evaluating such recommendations, the Governance and Nominating Committee seeks to achieve a balance of experience, knowledge, expertise, and capability on the Board of Directors and to address the membership criteria set forth under “Director Selection Process and Qualifications” below. There are no differences in the manner in which the Governance and Nominating Committee evaluates nominees for director based on whether the nominee is recommended by a stockholder or otherwise. Any stockholder recommendations for consideration by the Governance and Nominating Committee should be sent, together with the information required by Article II of our by-laws, c/o: Ambac Financial Group, Inc., Attn: Corporate Secretary, One World Trade Center, New York, New York 10007. Stockholder nominations for directors that a stockholder wishes to have considered at a meeting of stockholders should be made in accordance with the provisions of our by-laws, as described under “Other Questions related to the Meeting or Ambac-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?” above.

Director Selection Process and Qualifications

Our Governance and Nominating Committee will evaluate and recommend candidates for membership on the Board of Directors consistent with our Corporate Governance Guidelines regarding the selection of director nominees. Pursuant to these guidelines, the Governance and Nominating Committee screens candidates and evaluates the qualifications of the persons nominated by or recommended by our stockholders for membership to our Board. The Governance and Nominating

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Committee also considers each candidate's time commitments, including memberships on other public company boards and board committees.

In evaluating non-incumbent candidates for the Board, the Governance and Nominating Committee reviews the composition of the Board as a whole, as well as the committees, and assesses the appropriate knowledge, experience, skills, expertise and gender and ethnic diversity in the context of the current make-up and perceived needs of the Board at the time of consideration. It also reviews the composition of the Board to ensure that it contains at least the minimum number of independent directors required by applicable law and stock exchange listing requirements. Candidates also are evaluated in light of other factors, such as those relating to service on other boards of directors and other professional commitments. We believe that it is important to have a Board that is reflective of the core values and diversity of our key constituents including our employees, clients and partners, and stockholder base.

The Governance and Nominating Committee uses a variety of methods for identifying and evaluating nominees for directors. The Committee considers the current directors who have expressed an interest in and that continue to satisfy the criteria for serving on the Board as set forth in our Corporate Governance Guidelines. Other nominees who may be proposed by current directors, members of management or by stockholders are also considered. The Committee may, at Ambac’s expense, engage search firms, consultants and other advisors to identify, screen and/or evaluate candidates in order to ensure that the Committee has a pool of qualified candidates with diverse experiences.

The Governance and Nominating Committee recommends director nominees who are ultimately approved by the full Board of Directors.

Executive Sessions

Executive sessions of independent directors are held in connection with each regularly scheduled meeting of the Board of Directors and at other times as appropriate. The Board of Directors’ policy is to hold executive sessions without the presence of management, including the Chief Executive Officer.

Outside Advisors

Our Board of Directors and each of its committees may retain outside advisors and consultants of their choosing at our expense. The Board of Directors and its committees need not obtain management’s consent to retain outside advisors.

Board Effectiveness

The Governance and Nominating Committee conducted the Board's annual self-evaluation process in 2024. The effectiveness of the Board as a whole, and each of its individual committees, was assessed against the roles and responsibilities set forth in Ambac's Corporate Governance Guidelines, the relevant committee charters, and best practices. Matters considered as part of the evaluation included:

•the effectiveness of discussion and debate at Board and committee meetings;

•the effectiveness of Board and committee processes and in interacting with management;

•the quality and timeliness of Board and committee agendas, and preparation of reference materials to inform the Board and committees and support effective decision making; and

•the composition of the Board and each committee, focusing on the blend of skills, experience, independence and knowledge of the group.

This self-evaluation process was managed by the Board Chair, who is also a member of the Governance and Nominating Committee.

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Corporate Governance Guidelines

The Corporate Governance Guidelines reflect the Board's commitment to monitor the effectiveness of policy and decision making at both the Board and management levels, with a view to enhancing long term stockholder value. The Corporate Governance Guidelines address, among other things, such topics as the role of directors; goals and development of long term strategy; size of the Board; other public company Board memberships; Board membership criteria; term limits; Board meeting procedures; and retirement policy. Ambac’s Corporate Governance Guidelines can be found in the Corporate Governance section of Ambac’s Investor Relations website at https://ambac.com/investor-relations/governance/governance-documents/default.aspx.

Code of Business Conduct and Ethics

Ambac has a Code of Business Conduct and Ethics which reflects the Board's commitment to maintaining strong standards of integrity for handling business situations appropriately and effectively. The Code of Business Conduct and Ethics can be found in the Corporate Governance section of Ambac’s Investor Relations website at https://ambac.com/investor-relations/governance/governance-documents. Ambac will disclose on its website any amendment to, or waiver from, a provision of its Code of Business Conduct and Ethics that applies to its Chief Executive Officer, Chief Financial Officer or Chief Accounting Officer. Charters for Ambac's Audit Committee, Governance and Nominating Committee, Strategy Committee and Compensation Committee are also available in the Corporate Governance section of Ambac’s Investor Relations website at https://ambac.com/investor-relations/governance/governance-documents.

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Board Compensation Arrangements for Non-Employee Directors

Ambac's director compensation program is designed to enable continued attraction and retention of highly qualified non-employee directors by ensuring that director compensation is reflective of the time, effort, expertise, and accountability required of board membership. The program is structured to recognize the unique nature of our business and the level of experience and oversight needed at the Board level, particularly with respect to overseeing Ambac's expansion into specialty property and casualty insurance and insurance distribution. It is essential that our Board members not only understand the risks that the Company faces and the steps that management is taking to manage those risks, but to also have a deep understanding of the appropriate level of risk for the Company as it pursues its strategy for the specialty property and casualty insurance and insurance distribution businesses. Additionally, it is critical that our non-employee director compensation program is appropriately designed to attract and retain Board members that are highly capable and well-suited to help us effectively achieve our goals.

The amount and composition of total compensation paid to our non-employee directors is considered in light of competitive compensation levels for directors in the financial services industry. The Governance and Nominating Committee uses this information to provide a general review of market pay levels and practices and to ensure that it makes informed decisions regarding our non-employee director compensation program. In 2023, the Governance and Nominating Committee reviewed the non-employee director compensation program that was put in place for the 2024 fiscal year, including comparisons to director compensation programs at other similarly situated companies. The Governance and Nominating Committee concluded that no changes were appropriate for the 2024 fiscal year. This conclusion was based on the Committee’s views that the Company continued to face many of the same risks and issues as it had faced in recent years and was in the early stage of new business. The Committee further noted that the workload of the directors remained similar to that of recent years in overseeing the activities of the Company and the complexity of the issues faced by the Company, including the management of litigation and other risks confronting the legacy financial guarantee business, pursuit of strategic initiatives for the legacy financial guarantee insurance business, and the continued development of the specialty property and casualty insurance and insurance distribution businesses through acquisitions and organic development. The Committee will review the compensation program for non-employee directors on an annual basis to assess whether such compensation is appropriate in light of directors’ time commitments and contributions as well as the complexity of the business.

Director Compensation Program Components

The annual compensation for non-employee directors generally consists of both a cash and equity component. The compensation components are designed to compensate members for their service on the Board of Directors and its committees, to create an incentive for continued service on the Board, and to align the interests of directors and stockholders. In furtherance of such alignment, a significant portion of each non-employee director’s annual compensation is at-risk and granted in the form of restricted stock units on the first business day of each calendar quarter. These quarterly grants vest on the one year anniversary of the grant date, subject to accelerated vesting under certain circumstances. Restricted stock units granted that have vested will not settle and convert into shares of common stock until the director resigns from, or otherwise ceases to be a member of, the Board of Directors of Ambac or certain other circumstances occur, such as a change in control.

Upon a non-employee director’s first appointment or election to our Board of Directors, such non-employee director will receive a one-time off-cycle pro-rata grant of restricted stock units, based on his or her expected time of service on the Board of Directors prior to the next quarterly restricted stock unit grant.

Mandatory Director Shareholding Requirements

To further align the interests of our Board of Directors with our stockholders, our Non-Employee Director Stock Ownership Policy requires each non-employee director to acquire and hold shares of our common stock equal to the lesser of $800,000 in value or 40,000 shares or within five years of becoming a director. This requirement may be satisfied by restricted stock unit holdings and other share acquisitions. All of our directors currently meet the ownership requirements, other than Ms. Matus who only joined the Ambac Board of Directors in 2023.

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Compensation for Non-Employee Directors

Our non-employee director compensation is paid as follows:

•An annual cash retainer of $100,000, paid in monthly installments, and four quarterly grants of $50,000 of stock-based compensation, comprised of restricted stock units of Ambac (rounded up to the nearest whole unit), with one year vesting from the grant date, as permitted under Ambac’s 2024 Incentive Compensation Plan; and

•The Chairman of the Board received an additional annual fee of $125,000; the Audit Committee Chair received an additional annual fee of $35,000; the Compensation Committee Chair received an additional annual fee of $25,000; and the chairs of each of the Governance and Nominating Committee and the Strategy Committee received an additional annual fee of $15,000.

In addition, Ambac reimburses its directors for reasonable out-of-pocket expenses in connection with their Board service, including attendance at Board of Directors and committee meetings.

The following table summarizes compensation paid to non-employee directors during 2024.

(1) Fees earned or paid in cash include an annual cash retainer and chairman or committee chair fees.

(2) The value of the restricted stock units (“RSUs”) received in 2024 and reported in the table above is based on the grant date fair value of awards computed in accordance with FASB ASC Topic 718. The grant date fair values of the quarterly RSUs granted to each non-employee director on January 1, 2024, April 1, 2024, July 1, 2024 and October 1, 2024 were $51,862, $51,101, $46,274 and $50,411, respectively. The number of RSUs granted on each grant date is set forth in the table below and was calculated based on an average closing price of Ambac common stock on the NYSE for the immediately preceding twenty trading days prior to the grant date:

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COMMON STOCK OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table shows the amount of our common stock beneficially owned as of the record date, April 3, 2025, by those known to us to beneficially own more than 5% of our common stock, by our directors and named executive officers individually and by our directors and executive officers as a group.

The percentage of shares outstanding provided in the table is based on 51,091,190 shares of our common stock, par value $0.01 per share, outstanding as of April 3, 2025. Beneficial ownership is determined in accordance with the rules of the SEC and generally includes voting or investment power with respect to securities. The SEC’s rules generally attribute beneficial ownership of securities to each person who possesses, either solely or shared with others, the voting power or investment power, which includes the power to dispose of those securities. Under these rules, one or more persons may be a deemed beneficial owner of the same securities and a person may be deemed a beneficial owner of securities to which such person has no economic interest.

Except as otherwise indicated in the footnotes to this table, each of the beneficial owners listed has, to our knowledge, sole voting and investment power with respect to the indicated shares of Common Stock. Unless otherwise indicated, the address for each beneficial owner who is also a director or executive officer is c/o Ambac Financial Group, Inc., One World Trade Center, New York, New York 10007.

• Beneficial ownership representing less than 1% is denoted with an asterisk (*).

(1)The share ownership listed in the table includes shares of our common stock that are subject to issuance in the future with respect to RSUs, in the following aggregate amounts: Mr. Haft, 119,140 shares; Ms. Iglesias, 54,996 shares; Ms. Lamm-Tennant, 94,209 shares; Ms. Matus, 26,398 shares; Mr. Price, 26,398 shares; and Mr. Stein, 155,026 shares. The RSUs granted to each of our non-executive directors shall not settle and convert into shares of common stock until such director resigns from, or otherwise ceases to be a member of, the Board of Directors of the Company. Each RSU represents a contingent right to receive one share of the Company’s common stock. RSUs granted to our directors and named executive officers that vest more than 60 days after the Record Date for voting at the Annual Meeting have not been included in the table above in accordance with SEC rules.

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(2)In computing the number of shares of common stock beneficially owned by a person and the percentage ownership of that person, we deemed as outstanding shares of common stock subject to options, RSUs or warrants held by that person that are currently exercisable or exercisable within 60 days of the Record Date. We did not deem these shares outstanding, however, for the purpose of computing the percentage ownership of any other person. Each holder of common stock as of the record date is entitled to one vote per share of common stock on all matters submitted to our stockholders for a vote.

(3)According to the Schedule 13G/A filed on April 3, 2025, BlackRock Inc. beneficially owned 4,002,154 shares of our Common Stock. BlackRock Inc. reported sole voting power with respect to 3,908,064 shares and sole dispositive power with respect to 4,002,154 shares. The address of BlackRock Inc. is 50 Hudson Yards, New York, New York 10001.

(4)According to the Schedule 13G/A filed on January 30, 2025, The Vanguard Group beneficially owned 3,216,048 shares of our Common Stock. The Vanguard Group reported shared voting power with respect to 31,516 shares, sole dispositive power with respect to 3,135,010 shares, and shared dispositive power with respect to 81,038 shares. The address of The Vanguard Group is 100 Vanguard Blvd., Malvern, Pennsylvania 19355.

(5)According to the Schedule 13G filed on February 9, 2024, Dimensional Fund Advisors LP beneficially owned 2,603,679 shares of our Common Stock. Dimensional Fund Advisors LP reported sole power to vote or direct the vote with respect to 2,551,011 shares, and sole dispositive power with respect to 2,603,679 shares. The address of Dimensional Fund Advisors LP is 6300 Bee Cave Road, Building One, Austin, TX 78746.

(6)See Note 1 to the Consolidated Financial Statements in Part II, Item 8 of the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 for description of the limitations on voting and transfer of Ambac’s common stock pursuant to Ambac’s Amended and Restated Certificate of Incorporation. Ambac has determined that the holdings described above do not violate the restrictions set forth in its Amended and Restated Certificate of Incorporation.

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EXECUTIVE COMPENSATION

Executive Officers

The names of our executive officers and their ages, positions, and biographies as of April 25, 2024 are set forth below. Our executive officers are appointed by, and serve at the discretion of, our Board.

Claude LeBlanc was appointed President and Chief Executive Officer of Ambac effective January 1, 2017. See full biography under “Board of Directors - Directors” above.

David Barranco has served as Senior Managing Director of Ambac since February 2012. Mr. Barranco is the head of Risk Management, a position he has held since October 2016. Mr. Barranco has executive responsibility for risk remediation, credit risk management, surveillance and other related risk management responsibilities across AAC's insured portfolio. Previously, he was head of the Restructuring Group and had responsibility for corporate development and strategy. Since September 2011, Mr. Barranco has served as Executive Director of Ambac Assurance UK Limited, Ambac’s London-based financial guarantee subsidiary. Mr. Barranco joined Ambac in 1999.

Robert B. Eisman has served as the Chief Accounting Officer, Controller, and a Senior Managing Director of Ambac since January 2010. Mr. Eisman is responsible for establishing Ambac’s U.S. GAAP and Ambac Assurance Corporation's U.S. statutory accounting policies and managing their respective financial reporting in compliance with SEC and U.S. insurance regulatory requirements. He is also responsible for enterprise-wide budgeting and providing accounting services to Ambac’s subsidiaries, including Ambac Assurance UK Limited. Mr. Eisman joined Ambac in 1995 from KPMG LLP where he was an Audit Manager in the Financial Services group with a specialization in insurance companies.

Stephen M. Ksenak has served as Senior Managing Director and General Counsel of Ambac since July 2011. Mr. Ksenak has executive responsibility for managing Ambac’s legal affairs. Prior to joining Ambac as Vice President and Assistant General Counsel in 2002, Mr. Ksenak practiced law at King & Spalding LLP.

Daniel McGinnis has served as Chief Operating Officer and Senior Managing Director of Ambac since December 2021. Heoversees key business areas for both Ambac’s legacy Financial Guarantee and new Specialty Property and Casualty Insurance and Insurance Distribution businesses, including Operations, Technology and Human Resources. Mr. McGinnis brings over 25 years of experience as a senior insurance industry professional, having previously worked as Chief Underwriting Officer and Chief Operating Officer of CapSpecialty, Inc. Previous to CapSpecialty, Mr. McGinnis was Division Executive of the Small Business Division at American International Group (AIG). Previous to AIG, he was with American Reinsurance Company and Marsh USA, where he was Vice President of Finite Risk Underwriting and Vice President of Marsh Risk Finance, respectively.

R. Sharon Smith has served as Executive Vice President and Chief Strategy Officer since February 2023. Previously Ms. Smith served as Chief of Staff and Senior Managing Director of Ambac from May 2017 until February 2023. Ms. Smith has executive responsibility for Ambac's Corporate Services Group which encompasses certain key functions within the Company including, Strategy, Human Resources, Corporate Communications and Model Governance and Analytics. Ms. Smith joined Ambac from Syncora Guarantee Inc., ("Syncora"), where she served in numerous capacities during her tenure, including as Associate General Counsel and Head of Investor Relations. Ms. Smith was also General Counsel and Chief Compliance Officer for Camberlink LLC (a wholly owned subsidiary of Syncora). Earlier in her career, Ms. Smith was Vice President and Assistant General Counsel of the Corporate Securities Department of New York Life Investment Management

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LLC, and an attorney for Clifford Chance; Skadden, Arps, Slate, Meagher & Flom LLP and Weil, Gotshal & Manges LLP. Ms. Smith currently serves on the Board of Embrace Partners, Inc.

David Trick was named Executive Vice President of Ambac in November 2016. He has served as Chief Financial Officer of Ambac since January 2010 and as a Senior Managing Director from January 2010 until his appointment as Executive Vice President. Mr. Trick was interim President and Chief Executive Officer of AAC from January 2015 until March 2016. As Chief Financial Officer, Mr. Trick has executive responsibility for managing Ambac’s financial affairs, including financial reporting, asset and liability management, investment management, financial planning, tax strategy, capital resources, operations, capital markets and liquidity and investor relations. In addition, since May 2006, he has served as Treasurer of Ambac. Since September 2015, Mr. Trick has served as an Executive Director of Ambac Assurance UK Limited. Mr. Trick joined Ambac in 2005 from The Bank of New York Mellon, where he was a senior banker responsible for delivering strategic solutions to insurance industry clients with regard to a broad range of treasury, credit, and capital markets products.

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Compensation Discussion and Analysis

WE ASK THAT YOU VOTE TO APPROVE OUR 2025 SAY ON PAY PROPOSAL

At our 2025 Annual Meeting, our stockholders will again have an opportunity to cast an advisory say on pay vote on the compensation paid to our named executive officers. We ask that our stockholders vote to approve executive officer compensation. Please see “Proposal No. 2—Advisory Vote to Approve Named Executive Officer Compensation.”

This Compensation Discussion and Analysis (“CD&A”) describes our executive compensation program and decisions relating to the fiscal year 2024 compensation of our named executive officers (“NEOs”) identified in the table below.

Our Named Executive Officers

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