What changed in this filing

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Item 9A. Controls and Procedures

2026-03-04 compared with 2025-03-06 · 175 added, 142 removed, 322 unchanged (50% of the section changed)

1 unchanged sentence

Evaluation of Disclosure Controls and Procedures .

Ambac’s disclosure controls and procedures are designed to ensure that information required to be disclosed under the Securities Exchange Act of 1934, as amended, is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms, including without limitation that information required to be disclosed by Ambac in its SEC filings is accumulated and communicated to management, including the Chief Executive Officer (CEO) and Chief Financial Officer (CFO) as appropriate to allow for timely decisions regarding required disclosure.

Ambac’s Disclosure Committee assists the CEO and CFO in their responsibilities to design, establish, maintain and evaluate the effectiveness of disclosure controls and procedures.

Octave’s disclosure controls and procedures are designed to ensure that information required to be disclosed under the Securities Exchange Act of 1934, as amended, is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms, including without limitation that information required to be disclosed by Octave in its SEC filings is accumulated and communicated to management, including the Chief Executive Officer (CEO) and Chief Financial Officer (CFO) as appropriate to allow for timely decisions regarding required disclosure.

Octave’s Disclosure Committee assists the CEO and CFO in their responsibilities to design, establish, maintain and evaluate the effectiveness of disclosure controls and procedures.

The Disclosure Committee is responsible for, among other things, the oversight, maintenance and implementation of the disclosure controls and procedures, subject to the supervision and oversight of the CEO and CFO.

Ambac’s management, with the participation of its CEO and CFO, has evaluated the effectiveness of Ambac’s disclosure controls and procedures (as defined in rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934) as of December 31, 2024 and, the CEO and CFO have concluded that at that date Ambac’s disclosure controls and procedures were effective at the reasonable assurance level.

Octave’s management, with the participation of its CEO and CFO, has evaluated the effectiveness of Octave’s disclosure controls and procedures (as defined in Rules 13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934) as of December 31, 2025 and, the CEO and CFO have concluded that at that date Octave’s disclosure controls and procedures were effective at the reasonable assurance level.

Management’s Report on Internal Control Over Financial Reporting .

Management of Ambac is responsible for establishing and maintaining adequate internal control over financial reporting.

Ambac’s internal control over financial reporting is a process designed under the supervision of the CEO and CFO and overseen by Ambac’s Board of Directors to provide reasonable assurance regarding the reliability of financial reporting and the preparation of Ambac’s financial statements for external reporting purposes in accordance with U.S.

Management of Octave is responsible for establishing and maintaining adequate internal control over financial reporting.

Octave’s internal control over financial reporting is a process designed under the supervision of the CEO and CFO and overseen by Octave’s Board of Directors to provide reasonable assurance regarding the reliability of financial reporting and the preparation of Octave’s financial statements for external reporting purposes in accordance with U.S.

generally accepted accounting principles.

Ambac’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of assets of Ambac;

Octave’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of assets of Octave;

(ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with U.S.

generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of Ambac;

and (iii) provide reasonable assurance regarding the prevention or timely detection and remediation of unauthorized acquisition, use or disposition of Ambac’s assets that could have a material effect on the financial statements.

generally accepted accounting principles and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of Octave;

and (iii) provide reasonable assurance regarding the prevention or timely detection and remediation of unauthorized acquisition, use or disposition of Octave’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal controls over financial reporting may not prevent or detect misstatements.

1 unchanged sentence

inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Ambac management conducted an assessment of the effectiveness of Ambac’s internal control over financial reporting based on the criteria established in the Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

Ambac management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives.

Octave management conducted an assessment of the effectiveness of Octave’s internal control over financial reporting based on the criteria established in the Internal Control — Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

Octave management recognizes that any controls and procedures, no matter how well designed and operated, can provide only reasonable assurance of achieving their objectives.

Under guidelines established by the SEC, companies are permitted to exclude certain acquisitions from their first assessment of internal control over financial reporting following the date of acquisition.

Based on those guidelines, management’s assessment of the effectiveness of Ambac Financial Group Inc.’s internal control over financial reporting at December 31, 2024 excluded certain processes of Beat Capital Partners Limited which were not integrated into the Company’s existing internal control over financial reporting environment at December 31, 2024.

The excluded Beat Capital Partners Limited processes represented approximately 1% of the Company's total assets and approximately 17% of the Company’s total revenues, respectively.

Based on its evaluations, Ambac's management have concluded that, as of December 31, 2024, our internal control over financial reporting was effective based on the criteria articulated in the 2013 Internal Control - Integrated Framework, excluding the above noted processes of Beat Capital Partners Limited.

The effectiveness of our internal control over financial reporting as of December 31, 2024 has been audited by KPMG LLP, an independent registered public accounting firm, as stated in their report, which expressed an unqualified opinion on the effectiveness of Ambac’s internal control over financial reporting.

Based on those guidelines, management’s assessment of the effectiveness of Octave Specialty Group Inc.’s internal control over financial reporting at December 31, 2025 excluded certain processes of ArmadaCorp.

Limited which were not integrated into the Company’s existing internal control over financial reporting environment at December 31, 2025.

The excluded ArmadaCorp processes represented approximately 2% of the Company's total assets and approximately 2% of the Company’s total revenues, respectively.

Based on its evaluations, Octave's management has concluded that, as of December 31, 2025, our internal control over financial reporting was effective based on the criteria articulated in the 2013 Internal Control - Integrated Framework, excluding the above noted processes of ArmadaCorp.

The effectiveness of our internal control over financial reporting as of December 31, 2025 has been audited by KPMG LLP, an independent registered public accounting firm, as stated in their report, which expressed an unqualified opinion on the effectiveness of Octave’s internal control over financial reporting.

Changes in Internal Control Over Financial Reporting .

Ambac expects to complete the assessment of the design of Beat's internal controls over financial reporting by July 31, 2025.

Octave expects to complete the assessment of the design of ArmadaCorp internal controls over financial reporting by October 31, 2026.

There were no changes in the Company’s internal control over financial reporting that occurred during the fourth quarter of 2025 that materially affected, or are reasonably likely to materially affect, the Company's internal control over financial reporting.

Management has formally incorporated Octave Ventures into Octave's program for internal control over financial reporting effective August 1, 2025.

Accordingly, Octave Ventures is included in the scope of management's control assessments beginning with the third quarter of 2025.

The Company completed the sale of AAC on September 29, 2025 (refer to Sale of AAC in the Overview section of Item 2.

Management’s Discussion and Analysis of Financial Condition and Results of Operations).

Subsequent to the Sale, AAC continued to perform certain services for the Company under a transition support agreement between the parties.

These services included certain accounting and information technology activities that supported the preparation of the Company's

Octave Specialty Group, Inc.

2025 Form 10-K

Unaudited Consolidated Financial Statements included in Part 1 of this Form 10-Q.

Effective January 1, 2025, Octave Specialty Group, Inc.

changed the general ledger and consolidation system and certain related processes used for a substantial portion of its continuing operations.

Additional entities comprising OSG's continuing operations will be converting onto the new general ledger system in 2025 and 2026.

As part of its implementation, the Company evaluated the impact of this new system on its internal control over financial reporting and made changes to controls and procedures where necessary.

Other Information

In the last fiscal quarter, none of our directors or executive officers adopted , terminated , or modified any Rule 10b5-1 trading arrangement, or any non-Rule 10b5-1 trading arrangement.

In the last fiscal quarter, none of our directors or executive officers adopted , terminated , or modified any contract, instruction or written plan for the purchase or sale of company securities intended to satisfy the affirmative defense conditions of Rule 10b5-1(c) and/or any non-Rule 10b5-1 trading arrangement.

No other matters require disclosure.

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

Directors, Executive Officers and Corporate Governance

Information relating to AFG’s executive officers and directors, including its audit committee and audit committee financial experts, will be in AFG’s definitive Proxy Statement for its 2025 Annual Meeting of Stockholders which will be filed within 120 days of the end of our fiscal year ended December 31, 2024 (the “2025 Proxy Statement”) and is incorporated herein by reference.

Ambac has a Code of Business Conduct and Ethics which promotes management’s commitment to integrity and expresses Ambac’s standards for ethical behavior by providing guidelines for handling business situations appropriately.

This code can be found on Ambac’s website at www.ambac.com on the “Environmental, Social & Governance” page under "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.

Ambac’s corporate governance guidelines and the charters for the committees of the Board of Directors are also available on our website under the “Governance Documents” page.

Information relating to OSG’s executive officers and directors, including its audit committee and audit committee financial experts, will be in OSG’s definitive Proxy Statement for its 2026 Annual Meeting of Stockholders which will be filed within 120 days of the end of our fiscal year ended December 31, 2025 (the “2026 Proxy Statement”) and is incorporated herein by reference.

Octave has a Code of Business Conduct and Ethics which promotes management’s commitment to integrity and expresses Octave’s standards for ethical behavior by providing guidelines for handling business situations appropriately.

This code can be found on Octave’s website at www.octavegroup.com on the “Sustainability” page under "Governance Documents." Octave 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.

Octave’s corporate governance guidelines and the charters for the committees of the Board of Directors are also available on our website under the “Governance Documents” page.

The reference to our website address does not constitute inclusion or incorporation by reference of the information contained on our website in this Annual Report on Form 10-K or other filings with the SEC and the information contained on our website is not part of this document.

Executive Compensation

Information relating to Ambac’s executive officer and director compensation will be in the 2025 Proxy Statement and is incorporated herein by reference.

Information relating to Octave’s executive officer and director compensation will be in the 2026 Proxy Statement and is incorporated herein by reference.

Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters

Information relating to security ownership of certain beneficial owners of AFG’s common stock and information relating to the security ownership of AFG’s management, as well as information related to equity compensation plans, will be in the 2025 Proxy Statement and is incorporated herein by reference.

Information relating to security ownership of certain beneficial owners of OSG’s common stock and information relating to the security ownership of OSG’s management, as well as information related to equity compensation plans, will be in the 2026 Proxy Statement and is incorporated herein by reference.

Certain Relationships and Related Transactions, and Director Independence

Information relating to Ambac with respect to certain relationships and related transactions and director independence will be in the 2025 Proxy Statement and is incorporated herein by reference.

Information relating to Octave with respect to certain relationships and related transactions and director independence will be in the 2026 Proxy Statement and is incorporated herein by reference.

Principal Accountant Fees and Services

9 unchanged sentences

Schedule III — Supplementary Insurance Information

Octave Specialty Group, Inc.

2025 Form 10-K

Incorporated by Reference

Exhibit Description Form Filing Date Exhibit Number Filed Herewith

(2) Plan of Acquisition/Reorganization:

2.1 Second Modified Fifth Amended Plan of Reorganization of Ambac Financial Group, Inc., effective as of May 1, 2013

10-K 03/03/14 99.3

(3) Articles of Incorporation and bylaws:

3.1 A m ended and Restated Certificate of Incorporation of Ambac Fina n cial Group, Inc.

3.2 Amended By-Laws of Ambac Financial Group, Inc.

3.1 Amended and Restated Certificate of Incorporation of Octave Specialty Group, Inc.

8-K 11/10/25 3.1

Ambac Financial Group, Inc.

2024 Form 10-K

Incorporated by Reference

Exhibit Description Form Filing Date Exhibit Number Filed Herewith

3.2 Amended and Restated By-Laws of Octave Specialty Group, Inc.

8-K 11/10/25 3.2

(4) Instruments defining the rights of security holders, including indentures:

2 unchanged sentences

8-A 05/01/13 4.1

4.3 Fiscal Agency Agreement, dated as of July 19, 2010, by and between the Segregated Account of Ambac Assurance Corporation and The Bank of New York Mellon, as fiscal agent

10-K 03/03/14 4.10

4.4 Form of Surplus Note due June 7, 2020 issued by the Segregated Account of Ambac Assurance Corporation.(included in Exhibit 4.

4.5 Fiscal Agency Agreement, dated as of June 7, 2010, by and between Ambac Assurance Corporation and The Bank of New York Mellon, as fiscal agent

8-K 06/08/10 10.3

4.6 Amendment dated as of October 3, 2014 to Fiscal Agency Agreement dated as of June 7, 2010 by and between Ambac Assurance Corporation and The Bank of New York Mellon, as fiscal agent

10-Q 11/09/15 4.1

4.7 Form of Warrant Agreement to be entered into at the closing of the sale of Ambac Assurance Corporation to funds managed by Oaktree Capital Management, L.P.

4.3 Warrant Agreement, by and between Ambac Financial Group, Inc.

and American Acorn Holdings, LLC, dated as of September 29, 2025.

8-K 09/29/25 4.1

(10) Material contract and management compensation plans and arrangements:

(10) Material contracts and management compensation plans and arrangements:

10.1 Ambac Financial Group, Inc.'s Long-Term Incentive Compensation Plan

4 unchanged sentences

8-K 05/03/13 10.2

10.4 Form of Expense Sharing and Cost Allocation Agreement among Ambac Assurance Corporation, Ambac Financial Group, Inc.

and their respective subsidiaries and affiliates

10-K 03/01/23 10.5

10.4 Lease, dated as of March 1, 2011, by and between One State Street, LLC and Ambac Assurance Corporation

10-K 03/16/11 10.34

10.6 Settlement Agreement, dated as of June 7, 2010, by and among Ambac Assurance Corporation, Ambac Credit Products LLC, Ambac Financial Group, Inc.

and the parties listed on Schedule A thereto

10-Q 11/15/10 10.1

10.5 Ambac Financial Group, Inc.

3 unchanged sentences

10-K 02/29/16 10.27

10.9 Employment Agreement dated as of November 1, 2016 by and among Ambac Financial Group, Inc., Ambac Assurance Corporation and David Trick

10-Q 11/03/16 10.2

10.10 Amended and Restated Employment Agreement dated August 3, 2020 by and among Ambac Financial Group, Inc, Ambac Assurance Corporation and Claude LeBlanc.

10-Q 08/06/20 10.2

10.11 Employment Agreement dated as of January 4, 2017 by and among Ambac Financial Group, Inc., Ambac Assurance Corporation and Stephen Ksenak

8-K 01/06/17 10.1

10.12 Second Amended Plan of Rehabilitation of the Segregated Account of Ambac Assurance Corporation dated September 25, 2017, and effective as of February 12, 2018

10-K 02/28/18 10.38

10.13 Order Granting the Rehabilitator’s Motion to Further Amend the Plan of Rehabilitation and confirming the Second Amended Plan of Rehabilitation, as amended, Case No.

10-CV-1576 (Dane County, Wisconsin) dated January 22, 2018

10-K 02/28/18 10.39

Ambac Financial Group, Inc.

2024 Form 10-K

Incorporated by Reference

Exhibit Description Form Filing Date Exhibit Number Filed Herewith

10.14 Preferred Stock Repurchase and Support Agreement dated as of June 22, 2018, by and among Ambac Assurance Corporation (“AAC”), Ambac Financial Group, Inc.

and the holders of one or more series of the AAC’s outstanding Auction Market Preferred Shares

8-K 06/25/18 10.1

10.7 SUBLEASE dated as of January 30, 2019, between Advance Magazine Publishers Inc.

8 unchanged sentences

8-K 06/30/21 10.1

10.19 Settlement Agreement and Release dated as of October 6, 2022 by and among Bank of America Corporation and certain affiliates and Ambac Assurance Corporation (Portions of this exhibit have been omitted in reliance on Regulation S-K Item 601(b)(10)(iv))

10-K 03/01/23 10.34

10.20 Settlement Agreement and Release dated as of December 29, 2022 by and among Nomura Credit & Capital, Inc.

and Ambac Assurance Corporation.

(Portions of this exhibit have been omitted in reliance on Regulation S-K Item 601(b)(10)(iv))

10-K 03/01/23 10.35

10.21 Form of 2022 Restricted Stock Unit Award Agreement between Ambac Financial Group, Inc.

LeBlanc, Trick and Ksenak

10-Q 05/10/22 10.1

10.22 Form of 2022 Restricted Stock Unit Award Agreement between Ambac Financial Group, Inc.

Barranco, Eisman, McGinnis and Ms.

10-Q 05/10/22 10.2

10.23 Form of 2022 Performance Stock Unit Award Agreement between Ambac Financial Group, Inc.

LeBlanc, Trick and Ksenak

10-Q 05/10/22 10.3

10.24 Form of 2022 Performance Stock Unit Award Agreement between Ambac Financial Group, Inc.

Barranco, Eisman, McGinnis and Ms.

10-Q 05/10/22 10.4

10.25 Employment Agreement dated as of October 5, 2023, by and among Ambac Financial Group, Inc., Ambac Assurance Corporation and R.

8-K 10/06/23 10.1

10.11 Employment Agreement dated as of October 5, 2023, by and among Ambac Financial Group, Inc., Ambac Assurance Corporation and Daniel McGinnis

16 unchanged sentences

Def 14A 04/26/24 Appendix A

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

28 unchanged sentences

8-K 06/05/24 10.5

10.29 First Amendment to the Stock Purchase Agreement, by and between Ambac Financial Group, Inc.

and American Acorn Corporation, dated as of July 3, 2025.

8-K 07/07/25 2.1

10.30 Letter Agreement, by and between Ambac Financial Group, Inc.

and American Acorn Corporation, dated as of July 3, 2025.*

8-K 07/07/25 10.1

10.31 First Amendment dated as of June 10, 2025 to the Credit Agreement, by and between Ambac Financial Group, Cirrata V LLC, Cirrata Group, LLC, Cirrata V UK Ltd and UBS AG, dated as of August 1, 2024.

10-Q 08/07/25 10.3

10.32 Form of 2025 Performance Stock Unit Award Agreement between Ambac Financial Group, Inc.

LeBlanc, Trick, Ksenak, McGinnis and Ms.

10-Q 08/07/25 10.4

10.33 Form of 2025 Restricted Stock Unit Award Agreement between Ambac Financial Group, Inc.

LeBlanc, Trick, Ksenak, McGinnis and Ms.

10-Q 08/07/25 10.5

10.34 Investor Rights Agreement, by and between Ambac Financial Group, Inc.

and American Acorn Holdings, LLC, dated as of September 29, 2025.

8-K 09/29/25 10.1

10.35 Membership Interest Purchase Agreement, dated September 29, 2025, by and among Sirius Acquisitions Holding Company, Cirrata VI, LLC, Sirius Re Holdings, Inc., and Ambac Financial Group, Inc.

8-K 09/29/25 10.1

10.36 Commitment Letter, dated as of September 29, 2025, by and among Cirrata Group LLC, Cirrata V LLC, Cirrata V UK Limited, Cirrata VI, LLC, Truist Bank and Truist Securities, Inc.

8-K 09/29/25 10.2

10.37 Employment Agreement dated as of September 29, 2025 by and among Octave Specialty Group, Inc.

(formerly known as Ambac Financial Group, Inc.

and Claude LeBlanc.

8-K 09/29/25 10.1

Octave Specialty Group, Inc.

2025 Form 10-K

Incorporated by Reference

Exhibit Description Form Filing Date Exhibit Number Filed Herewith

10.38 Employment Agreement dated as of September 29, 2025 by and among Octave Specialty Group, Inc.

(formerly known as Ambac Financial Group, Inc.) and David Trick

8-K 09/29/25 10.2

10.39 Employment Agreement dated as of September 29, 2025 by and among Octave Specialty Group, Inc.

(formerly known as Ambac Financial Group, Inc.

8-K 09/29/25 10.3

10.40 Form of Restricted Stock Unit Agreement for Special RSU Award between Ambac Financial Group, Inc.

LeBlanc, Trick and Ms.

8-K 09/29/25 10.4

10.41 Form of Performance Stock Option Agreement for Special Performance-Based Stock Option Award between Ambac Financial Group, Inc.

LeBlanc, Trick and Ms.

8-K 09/29/25 10.5

10.42 Amendment No.

1 to 2024 Incentive Compensation Plan, dated as of September 26, 2025

8-K 09/29/25 10.6

10.43 Credit Agreement, dated as of October 31, 2025, by and among Cirrata Group LLC, Cirrata V LLC, Cirrata V UK Limited, Cirrata VI, LLC, ArmadaCorp Capital, LLC, ArmadaCare, LLC, Armada Administrators LLC, the several banks and other financial institutions and lenders from time to time party thereto, and Truist Bank*

8-K 11/03/25 10.1

10.44 Employment Agreement dated as of August 1 1 , 2025, by and among Ambac Financial Group, Inc.

and Lawrence Metz

(19) Insider Trading Policy

19.1 Ambac Insider Trading Policy

19.1 Octave Insider Trading Policy

(97) Recoupment Policy

97.1 Ambac Financial Group, Inc.

- Recoupment Policy 10-K 02/27/24 97.1

(99) Additional exhibits

99.1 Second Modified Fifth Amended Plan of Reorganization of Ambac Financial Group, Inc., effective as of May 1, 2013

97.1 Octave Specialty Group, Inc.

- Recoupment Policy

10-K 02/27/24 97.1

Other exhibits, filed or furnished, as indicated:

21.1 List of Subsidiaries of Ambac Financial Group, Inc.

21.1 List of Subsidiaries of Octave Specialty Group, Inc.

23.1 Consent of Independent Registered Public Accounting Firm

24.1 Power of Attorney for directors of Ambac Financial Group, Inc.

24.1 Power of Attorney for directors of Octave Specialty Group, Inc.

31.1 Certification of Chief Executive Officer Pursuant to Rules 13a-14(a) and 15d-14(a) Promulgated under the Securities Exchange Act of 1934, as amended

7 unchanged sentences

101.PRE XBRL Taxonomy Extension Presentation Linkbase Document.

Ambac Financial Group, Inc.

2024 Form 10-K

Incorporated by Reference

Exhibit Description Form Filing Date Exhibit Number Filed Herewith

101.DEF XBRL Taxonomy Extension Definition Linkbase Document.

1 unchanged sentence

++ Furnished herewith.

Ambac Financial Group, Inc.

* Certain schedules and other similar attachments to such agreement have been omitted pursuant to Item 601(a)(5) of Regulation S-K.

The Company will furnish a copy of such omitted documents to the SEC upon request.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

16 unchanged sentences

Total $ 269,848 $ 276,191 $ 293,708

(1) Excluded from the estimated fair value amount are equity securities with a carrying value of $ 20,618 as of December 31, 2024, that do not have readily determinable fair values and are carried on the balance sheet at cost, less impairment, and adjusted to fair value when observable price changes in identical or similar investments from the same issuer occur, as permitted under the Investments — Equity Securities Topic of the ASC, and an equity method investment of $ 177 as of December 31, 2024.

(1) Excluded from the estimated fair value amount are equity securities with a carrying value of $ 17,517 as of December 31, 2025, that do not have readily determinable fair values and are carried on the balance sheet at cost, less impairment, and adjusted to fair value when observable price changes in identical or similar investments from the same issuer occur, as permitted under the Investments — Equity Securities Topic of the ASC.

See the Report of Independent Registered Public Accounting Firm.

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

11 unchanged sentences

Investment in subsidiaries 645,507 679,150

Investment income due and accrued 269 545

Deferred tax asset 1,497 1,497

Other assets 8,750 21,476

17 unchanged sentences

( 33,473 ) ( 28,339 )

Total Ambac Financial Group, Inc.

Total Octave Specialty Group, Inc.

stockholders’ equity 715,790 798,364

2 unchanged sentences

See the Report of Independent Registered Public Accounting Firm.

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

14 unchanged sentences

Net income (loss) of subsidiaries ( 15,020 ) ( 29,770 ) ( 13,158 )

Net income (loss) from continuing operations

( 98,404 ) ( 59,282 ) ( 24,551 )

Net income (loss) from discontinued operations ( 163,288 ) ( 497,167 ) 28,183

Net income (loss) $ ( 261,692 ) $ ( 556,449 ) $ 3,632

10 unchanged sentences

Total other comprehensive income (loss) 196,918 ( 28,390 ) 92,797

Total comprehensive income (loss) attributable to Ambac Financial Group, Inc.

Total comprehensive income (loss) attributable to Octave Specialty Group, Inc.

$ ( 64,774 ) $ ( 584,839 ) $ 96,429

1 unchanged sentence

See the Report of Independent Registered Public Accounting Firm.

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

11 unchanged sentences

Cost of shares repurchased ( 4,510 ) ( 4,510 )

Changes to redeemable NCI 2,504 — — — — 2,504 —

Cost of warrants acquired 172 — — 172 — — —

Issuance of common stock 2 — 2 — — — —

Purchase of Ambac Assurance auction market preferred shares 1,131 — — — — 1,131 —

Changes to NCI 4,797 — — — — 4,797 —

Balance at December 31, 2023 1,361,658 — 467 291,761 ( 160,046 ) 1,246,048 ( 16,573 )

Total comprehensive income (loss) 96,430 — 92,797 3,633 —

Total Comprehensive net income (loss) ( 584,839 ) — ( 28,390 ) ( 556,449 ) —

Stock-based compensation 8,995 8,995

2 unchanged sentences

Changes to NCI ( 4,278 ) 1,044 ( 5,322 )

Issuance of common stock 29,229 22 29,207 — —

Balance at December 31, 2024 798,364 — 489 331,007 ( 188,436 ) 683,642 ( 28,339 )

4 unchanged sentences

Changes to NCI ( 6,031 ) 12,146 ( 18,177 ) —

Issuance of common stock 29,229 — 22 29,207 — — —

Issuance of warrants in connection with sale of AAC 17,000 — — 17,000 — — —

Balance at December 31, 2025 $ 715,790 $ — $ 489 $ 369,860 $ 8,483 $ 370,431 $ ( 33,473 )

1 unchanged sentence

See the Report of Independent Registered Public Accounting Firm.

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

5 unchanged sentences

Net income (loss) $ ( 261,692 ) $ ( 556,449 ) $ 3,632

Loss from discontinued operations 163,288 497,167 —

Net income (loss) from continuing operations $ (98,404) $ (59,282) $ 3,632

Adjustments to reconcile net income loss to net cash used in operating activities:

Net (income) loss of subsidiaries 526,937 ( 15,027 ) ( 541,773 )

Amortization of bond premium and discount — — ( 7,378 )

Net investment gains (losses), including impairments 498 ( 55 ) 13,664

Equity in undistributed net (income) loss of subsidiaries 15,020 29,770 ( 15,027 )

Increase (decrease) in current income taxes payable 1,613 ( 1,970 ) ( 1,674 )

9 unchanged sentences

Change in other investments 3,146 ( 1,749 ) ( 2,715 )

Proceeds from sale, net of cash transferred 407,300 — —

Other, net ( 7,115 ) — —

Net cash provided by (used in) investing activities 428,285 94,500 16,166

2 unchanged sentences

Cost of shares acquired ( 29,942 ) ( 11,699 ) ( 4,510 )

Issuance of warrants 17,000 — —

Net cash (used in) financing activities ( 397,546 ) ( 82,516 ) ( 20,560 )

6 unchanged sentences

Non-cash financing activity:

Ambac common stock issued as partial consideration to acquire Beat $ 29,229 $ — $ —

Octave common stock issued as partial consideration to acquire Octave Ventures $ — $ 29,229 $ —

The condensed financial statements should be read in conjunction with the consolidated financial statements and notes thereto and the following notes.

See the Report of Independent Registered Public Accounting Firm.

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

3 unchanged sentences

(Dollar Amounts in Thousands)

The condensed financial information of Ambac Financial Group, Inc.

(“AFG” or the “Registrant”) as of December 31, 2024 and 2023, and for the three years in the period ended December 31, 2024, should be read in conjunction with the consolidated financial statements of AFG Financial Group, Inc.

The condensed financial information of Octave Specialty Group, Inc.

(“OSG” or the “Registrant”) as of December 31, 2025 and 2024, and for the three years in the period ended December 31, 2025, should be read in conjunction with the consolidated financial statements of Octave Specialty Group, Inc.

and Subsidiaries and the notes thereto included in this Annual Report on Form 10-K for the year ended December 31, 2025.

Investments in subsidiaries are accounted for using the equity method of accounting.

AFG, headquartered in New York City, is an insurance holding company incorporated in the state of Delaware on April 29, 1991.

AFG files a consolidated U.S.

OSG, headquartered in New York City, is an insurance holding company incorporated in the state of Delaware on April 29, 1991.

OSG files a consolidated U.S.

federal income tax return with its 80% or greater owned U.S.

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Beat's US subsidiaries file separate U.S.

Federal income tax returns as they are not directly owned by AFG for tax purposes.

AFG and its subsidiaries also file separate or combined income tax returns in various states, local and foreign jurisdictions.

federal income tax returns as they are not directly owned by OSG for tax purposes.

OSG and its subsidiaries also file separate or combined income tax returns in various states, local and foreign jurisdictions.

As of December 31, 2025, the Company has $ 1,690,842 of NOLs, which if not utilized will begin expiring in 2030, and $ 118,910 of NOLs that carryforward indefinitely.

Discontinued Operations

On June 4, 2024, AFG entered into a stock purchase agreement (the "Purchase Agreement") with American Acorn Corporation (the “Buyer”), a Delaware corporation owned by funds managed by Oaktree Capital Management, L.P., pursuant to which and subject to the conditions set forth therein, AFG will sell all of the issued and outstanding shares of common stock of AAC owned by AFG to the Buyer for aggregate consideration of $ 420,000 in cash, and will issue to the Buyer a warrant to purchase AFG common stock representing 9.9 % of the fully diluted shares of AFG’s common stock as of March 31, 2024, pro forma for the issuance of the Warrant (the "AAC Sale").

The terms of the AAC Sale as contemplated by the Purchase Agreement provide that, at the closing of the AAC Sale (the “Closing”), Buyer will acquire complete ownership of the common stock of AAC and all of its wholly owned subsidiaries, including Ambac UK.

For further information, see Note 5.

Discontinued Operation included in Part II, Item 8 of this Form 10-K .

Ambac Financial Group, Inc.

On September 29, 2025, the Company completed the sale of AAC pursuant to the June 4, 2024, stock purchase agreement (the "Purchase Agreement") with American Acorn Corporation (the “Buyer”), a Delaware corporation owned by funds managed by Oaktree Capital Management, L.P., pursuant to which OSG sold all of the issued and outstanding shares of common stock of AAC, a wholly-owned subsidiary of OSG, to Buyer for $ 420,000 in cash (the "Sale").

The Buyer also made an additional payment to OSG in an amount of $ 4,300 .

In the Sale, Buyer acquired complete common equity ownership of AAC and all of its wholly owned subsidiaries, including Ambac Assurance UK Limited.

In connection with and pursuant to the Purchase Agreement, OSG issued to Buyer a warrant exercisable for 5,092,707 shares of common stock, par value $ 0.01 , of OSG.

Refer to Note 5.

Discontinued Operations of the Notes to the Consolidated Financial Statements under Part II, Item 8 in this Annual Report on Form 10-K for further details on the sale of AAC.

For all periods leading up to the Sale, AAC's results of operations and OSG's loss on sale are reported within Net income (loss) from discontinued operations before tax on the Consolidated Statement of Comprehensive Income (Loss).

Discontinued Operations of the Notes to the Consolidated Financial Statements under Part II, Item 8 of this Annual Report on Form 10-K for additional information.

Acquisition of ArmadaCorp

On October 31, 2025, the Company closed on the acquisition of ArmadaCorp for a purchase price of $ 250,000 .

The Company purchased all of the issued and outstanding limited liability company interests in ArmadaCorp from Sirius Re Holdings, Inc.

and Sirius Acquisitions Holding Company, funded in part by $ 120,000 of loans obtained under new credit facilities.

Refer to Note 4.

Business Combination in Part II, Item 8 in this Annual Report on Form 10-K for further details on the acquisition of ArmadaCorp.

ArmadaCorp includes an MGA/U that focuses on supplemental health and benefit products for C-suite executives and other key talent.

ArmadaCorp creates and distributes supplemental benefit solutions and insurance products.

ArmadaCorp's differentiated product offering in the A&H market provides both line of business and product diversification to the Company, while also increasing exposure to non-correlated A&H business lines.

ArmadaCorp also provides clients with tools to navigate the healthcare system, including services that help match individuals with physicians suited to their personal needs, and maintains a provider of third-party administration services for insurance carriers that distribute the benefit products and handle claims.

Effective September 1, 2025, OSG's wholly owned subsidiary, Octave Partners LLC ("Octave Partners"), exercised its option to convert its $ 3,500 convertible note investment in Pivix Specialty Insurance Services ("Pivix"), an excess and surplus lines MGA/U, into common stock.

As a result, Octave Partners now has an approximately 74 % controlling stake in Pivix when combined with its previous 17 % minority equity interest and includes Pivix in its consolidated financial statements.

Immaterial Correction of Prior Period Error

As disclosed in Note 2.

Basis of Presentation, the Company identified an immaterial prior period error in the Consolidated Stockholders’ Equity statement related to the redeemable non-controlling interest associated with the redemption value adjustment recorded under ASC 810-10.

In Schedule II, Condensed Financial Information of Registrant (Parent Company Only) Condensed Balance Sheet, the investment in subsidiaries balance and retained earnings as of December 31, 2024 were corrected by $ 58,542 to reflect the correction to redeemable non controlling interest, which impacted Total assets and Total liabilities and stockholders equity.

Octave Specialty Group, Inc.

2025 Form 10-K

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

AND SUBSIDIARIES

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Form 10-K Summary .

Ambac Financial Group, Inc.

Octave Specialty Group, Inc.

2025 Form 10-K

Pursuant to the requirements of Section 13 or 15(d) of the Securities Exchange Act of 1934, the Registrant has caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

AMBAC FINANCIAL GROUP, INC.

OCTAVE SPECIALTY GROUP, INC.

March 4, 2026 By:

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David Trick (Principal Financial Officer)

/S/ ROBERT B.

EISMAN Senior Managing Director and Chief Accounting Officer March 6, 2025

Eisman (Principal Accounting Officer)

/S/ CRISTINA AHN Chief Accounting Officer March 4, 2026

Cristina Ahn (Principal Accounting Officer)

HAFT* Director March 4, 2026

6 unchanged sentences

PRICE* Director March 4, 2026

/S/ STEPHEN M.

KSENAK Attorney-in-fact March 6, 2025

Ambac Financial Group, Inc.

/S/ LAWRENCE F.

METZ Attorney-in-fact March 4, 2026

Octave Specialty Group, Inc.

2025 Form 10-K

Compared sentence by sentence after normalising whitespace, quotation marks, case and digits, so re-formatting and restated figures do not read as changed language. Wording changes appear as one removal and one addition. The current filing and the prior one are authoritative.

What changed 10-K

Item 9A. Controls and Procedures