What changed in this filing

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Item 9A. Controls and Procedures

2026-03-02 compared with 2025-02-27 · 48 added, 22 removed, 143 unchanged (33% of the section changed)

4 unchanged sentences

Based upon that evaluation, the Chief Executive Officer and Chief Financial Officer concluded that as of December 31, 2025, the Company's disclosure controls and procedures were effective to provide reasonable assurance that they would meet their objectives.

We completed the acquisition of TriMas Aerospace Germany on February 17, 2025, and have not yet included this acquisition in our assessment of the effectiveness of our internal control over financial reporting.

Accordingly, pursuant to the SEC's general guidance that an assessment of a recently acquired business may be omitted from the scope of an assessment in the year of acquisition, the scope of our assessment of the effectiveness of our disclosure controls and procedures does not include TriMas Aerospace Germany.

TriMas Aerospace Germany accounted for $43.5 million of total assets and $23.9 million of total net sales included within income from discontinued operations, net of income taxes, as of and for the year ended December 31, 2025.

Management's Annual Report on Internal Control Over Financial Reporting

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In order to ensure that the Company's internal control over financial reporting is effective, management regularly assesses such controls and did so most recently for its financial reporting as of December 31, 2025.

Management's assessment of internal control over financial reporting as of December 31, 2025 excludes internal control over financial reporting related to TriMas Aerospace Germany (acquired on February 17, 2025), which accounted for $43.5 million of total assets and $23.9 million of net sales included within income from discontinued operations, net of income taxes, as of and for the year ended December 31, 2025.

Management's assessment was based on criteria for effective internal control over financial reporting described in Internal Control—Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission.

7 unchanged sentences

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements and financial statement schedule as of and for the year ended December 31, 2025, of the Company and our report dated February 26, 2026, expressed an unqualified opinion on those financial statements and financial statement schedule.

As described in Annual Report on Internal Control over Financial Reporting , management excluded from its assessment the internal control over financial reporting at TriMas Aerospace Germany, which was acquired on February 17, 2025, and whose financial statements constitute $43.5 million of total assets and $23.9 million of total net sales included within income from discontinued operations, net of income taxes of the consolidated financial statement amounts as of and for the year ended December 31, 2025.

Accordingly, our audit did not include the internal control over financial reporting at TriMas Aerospace Germany.

Basis for Opinion

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Detroit, Michigan

February 27, 2025

March 2, 2026

Changes in disclosure controls and procedures

37 unchanged sentences

001-10716), unless otherwise noted.

2.1 Equity Purchase Agreement, dated November 4, 2025, among TriMas Corporation, TriMas Company LLC, Aero Products Group LLC, TriMas International Holdings LLC, Rieke Germany GmbH & Co.

KG, and Takeoff Buyer, Inc., incorporated by reference to Exhibit 2.1 to the Company’s Current Report on Form 8-K filed on November 5, 2025.**

3.1 Fourth Amended and Restated Certificate of Incorporation of TriMas Corporation, incorporated by reference to Exhibit 3.1 to the Company’s Quarterly Report on Form 10-Q filed on August 3, 2007.

13 unchanged sentences

10.9 2013 Form of Indemnification Agreement, incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on November 13, 2013.*

10.10 Offer Letter between TriMas Corporation and Thomas A.

Amato dated July 23, 2016, incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on October 27, 2016.

10.10 Second Replacement Revolving Facility Amendment, dated as of March 29, 2021, among TriMas Corporation, TriMas Company LLC, the subsidiary borrowers party thereto, JPMorgan Chase Bank, N.A., as administrative agent, and the other agents and Lenders party thereto, incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on March 30, 2021.**

10.12 Offer Letter between TriMas Corporation and Scott Mell dated March 15, 2021, incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on July 29, 2021.*

10.11 Executive Severance / Change in Control Policy, incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on August 11, 2021.*

1 unchanged sentence

10.13 Form of Restricted Stock Units Agreement (Three-Year Vest) - 2023 LTI - under the 2017 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on April 27, 2023.*

10.16 Form of Performance Stock Units Agreement - 2023 LTI - under the 2017 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q filed on April 27, 2023.*

10.17 Form of Restricted Stock Units Agreement (Three-Year Vest) - 2023 LTI - under the 2017 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on April 27, 2023.*

10.18 Form of Restricted Stock Units Agreement (Board of Directors) (One-Year Vest) - 2023 LTI - under the 2017 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.3 to the Company’s Quarterly Report on Form 10-Q filed on April 27, 2023.*

10.14 TriMas Corporation 2023 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on May 11, 2023.*

3 unchanged sentences

10.18 Form of Restricted Stock Units Agreement (Board of Directors) (One-Year Vest) - 2024 LTI - under the 2023 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.3 to the Company’s Quarterly Report on Form 10-Q filed on April 30, 2024.*

10.19 Eighth Amendment to the Credit Agreement, dated as of March 31, 2025, by and among TriMas Corporation, TriMas Company LLC, certain other subsidiaries of TriMas Corporation party thereto and JPMorgan Chase Bank, N.A., as Administrative Agent, and the various lenders from time to time thereto, incorporated by reference to Exhibit 10.1 to the Company’s Current Report on Form 8-K filed on April 1, 2025.**

10.20 Form of Performance Stock Units Agreement - 2025 LTI - under the 2023 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on April 29, 2025.*

10.21 Form of Restricted Stock Units Agreement (Three-Year Ratable Vest) - 2025 LTI - under the 2023 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.3 to the Company’s Quarterly Report on Form 10-Q filed on April 29, 2025.*

10.22 Form of Restricted Stock Units Agreement (One-Year Cliff Vest) - 2025 LTI - under the 2023 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.4 to the Company’s Quarterly Report on Form 10-Q filed on April 29, 2025.*

10.23 Form of Restricted Stock Units Agreement (Two-Year Ratable Vest) - 2025 LTI - under the 2023 Equity and Incentive Compensation Plan, incorporated by reference to Exhibit 10.5 to the Company’s Quarterly Report on Form 10-Q filed on April 29, 2025.*

10.24 Transition and Separation Agreement between TriMas Corporation and Thomas A.

Amato dated January 4, 2025, incorporated by reference to Exhibit 10.6 to the Company’s Quarterly Report on Form 10-Q filed on April 29, 2025.*

10.25 Form of February 2025 Executive Retention Award letter agreement, incorporated by reference to Exhibit 10.7 to the Company’s Quarterly Report on Form 10-Q filed on April 29, 2025.*

10.26 Restricted Stock Units Agreement (Interim CFO) (One-Year Cliff Vest) under the 2023 Equity and Incentive Compensation Plan, dated as of March 20, 2025, by and between TriMas Corporation and Teresa M.

Finley, incorporated by reference to Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q filed on July 29, 2025.*

10.27 Offer Letter between TriMas Corporation and Thomas Snyder dated as of June 3, 2025, incorporated by reference to Exhibit 10.2 to the Company’s Quarterly Report on Form 10-Q filed on July 29, 2025.*

10.28 Restricted Stock Units Inducement Award Agreement (Three-Year Ratable Vest), dated as of June 24, 2025, by and between TriMas Corporation and Thomas Snyder, incorporated by reference to Exhibit 4.4 to the Company’s Registration Statement on Form S-8 (SEC File No.

333-288286) filed on June 24, 2025.*

10.29 Non-Qualified Stock Option Inducement Award Agreement (Five-Year Ratable Vest), dated as of June 24, 2025, by and between TriMas Corporation and Thomas Snyder, incorporated by reference to Exhibit 4.5 to the Company’s Registration Statement on Form S-8 (SEC File No.

333-288286) filed on June 24, 2025.*

10.30 Severance Agreement between TriMas Corporation and Thomas J.

Snyder dated as of June 23, 2025, incorporated by reference to Exhibit 10.5 to the Company’s Quarterly Report on Form 10-Q filed on July 29, 2025.*

10.31 Indemnification Agreement between TriMas Corporation and Thomas J.

Snyder dated as of June 23, 2025, incorporated by reference to Exhibit 10.6 to the Company’s Quarterly Report on Form 10-Q filed on July 29, 2025.*

10.32 Offer Letter between TriMas Corporation and Paul Swart dated November 30, 2025.*

10.33 Severance Agreement between TriMas Corporation and Paul Swart dated as of December 15, 2025.*

10.34 Indemnification Agreement between TriMas Corporation and Paul Swart dated as of December 15, 2025*

10.35 Ninth Amendment to the Credit Agreement, dated as of December 29, 2025, by and among TriMas Corporation, TriMas Company LLC and JPMorgan Chase Bank, N.A., as Administrative Agent, and the various lenders from time to time thereto.

19.1 Federal Securities Law Compliance Program.

18 unchanged sentences

TRIMAS CORPORATION

/s/ THOMAS A.

February 27, 2025 Name:

/s/ THOMAS J.

March 2, 2026 Name:

President and Chief Executive Officer

1 unchanged sentence

Name Title Date

/s/ THOMAS A.

AMATO President and Chief Executive Officer February 27, 2025

Amato (Principal Executive Officer) and Director

MELL Chief Financial Officer February 27, 2025

Mell (Principal Financial Officer and Principal Accounting Officer)

/s/ THOMAS J.

SNYDER President and Chief Executive Officer March 2, 2026

Snyder (Principal Executive Officer) and Director

SWART Chief Financial Officer March 2, 2026

Swart (Principal Financial Officer and Principal Accounting Officer)

/s/ HERBERT K.

PARKER Chairman of the Board of Directors February 27, 2025

BOEHNE Director February 27, 2025

PARKER Chairman of the Board of Directors March 2, 2026

BOEHNE Director March 2, 2026

/s/ JEFFREY A.

FIELKOW Director February 27, 2025

FIELKOW Director March 2, 2026

/s/ TERESA M.

FINLEY Director February 27, 2025

/s/ JEFFREY M.

GREENE Director February 27, 2025

STANAGE Director February 27, 2025

FINLEY Director March 2, 2026

SEDAGHAT Director March 2, 2026

/s/ ADRIANNE W.

SHAPIRA Director March 2, 2026

STANAGE Director March 2, 2026

/s/ DANIEL P.

TREDWELL Director February 27, 2025

TREDWELL Director March 2, 2026

PURSUANT TO ITEM 15(a)(2)

12 unchanged sentences

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