Steven J. Demetriou - 17 Nov 2025 Form 4 Insider Report for Amentum Holdings, Inc. (AMTM)

Reporting relationship: Executive Chair, Director
Issuer ticker: AMTM
Reported as of: 17 Nov 2025
Net transaction value: -$366,985
SEC form: 4
Accepted by SEC: 19 Nov 2025, 17:25:09 UTC
Prior SEC filing: 10 Feb 2026
Next SEC filing: 06 Jan 2026
Source filing: View source filing
Reporting owner signature: /s/ Mark Esposito, Attorney-in-Fact

Key filing fact

Steven J. Demetriou filed Form 4 for Amentum Holdings, Inc. (AMTM) on 19 Nov 2025.

Key facts

This page summarizes Steven J. Demetriou's Form 4 filing for Amentum Holdings, Inc. (AMTM).
4 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 19 Nov 2025, 17:25.

Change

Previous filing in this sequence was filed on 10 Feb 2026.
Current net transaction value: -$366,985.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001173003 Primary reporting owner

DEMETRIOU STEVEN J.

Relationship: Executive Chair, Director
Address: C/O AMENTUM HOLDINGS, INC., 4800 WESTFIELDS BOULEVARD, SUITE 400, CHANTILLY
Signature: /s/ Mark Esposito, Attorney-in-Fact
Signature date: 19 Nov 2025

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

AMTM transaction

Common Stock

Options Exercise

Transaction value
Shares: +43,396
Change %: +6.4%
Price
Shares after: 726,198
Date: 17 Nov 2025
Ownership: Direct
Footnotes: F1

AMTM transaction

Common Stock

Tax liability

Transaction value: $366,985
Shares: -17,077
Change %: -2.4%
Price: $21.49
Shares after: 709,121
Date: 17 Nov 2025
Ownership: Direct
Footnotes: F2

AMTM transaction

Common Stock

Award

Transaction value: $0
Shares: +111,355
Change %: +16%
Price: $0.000000
Shares after: 820,476
Date: 17 Nov 2025
Ownership: Direct
Footnotes: F3

AMTM holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 23,550
Date: 17 Nov 2025
Ownership: By Spouse

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

AMTM transaction Derivative

Restricted Stock Units

Options Exercise

Transaction value: $0
Shares: -43,396
Change %: -100%
Price: $0.000000
Shares after: 0
Date: 17 Nov 2025
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 43,396
Exercise price
Footnotes: F1, F4, F5

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 5 footnotes

Footnote F1

Represents distribution of AMTM common stock upon vesting of restricted stock units.

Footnote F2

Represents number of shares of AMTM common stock tendered for tax withholding upon vesting of restricted stock units.

Footnote F3

The restricted stock units shall vest and be delivered on the first anniversary of November 17, 2025.

Footnote F4

Each restricted stock unit represents a contingent right to receive one share of AMTM common stock.

Footnote F5

The restricted stock units awarded vested on November 17, 2025.