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

Role
Executive Chair, Director
Signature
/s/ Mark Esposito, Attorney-in-Fact
Stock symbol
AMTM
Transactions as of
Nov 17, 2025
Transactions value $
-$366,985
Form type
4
Date filed
11/19/2025, 05:25 PM
Previous filing
Nov 10, 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
DEMETRIOU STEVEN J. Executive Chair, Director C/O AMENTUM HOLDINGS, INC., 4800 WESTFIELDS BOULEVARD, SUITE 400, CHANTILLY /s/ Mark Esposito, Attorney-in-Fact 2025-11-19 0001173003

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction AMTM Common Stock Options Exercise +43.4K +6.36% 726K Nov 17, 2025 Direct F1
transaction AMTM Common Stock Tax liability -$367K -17.1K -2.35% $21.49 709K Nov 17, 2025 Direct F2
transaction AMTM Common Stock Award $0 +111K +15.7% $0.00 820K Nov 17, 2025 Direct F3
holding AMTM Common Stock 23.6K Nov 17, 2025 By Spouse

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction AMTM Restricted Stock Units Options Exercise $0 -43.4K -100% $0.00 0 Nov 17, 2025 Common Stock 43.4K Direct F1, F4, F5
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Represents distribution of AMTM common stock upon vesting of restricted stock units.
F2 Represents number of shares of AMTM common stock tendered for tax withholding upon vesting of restricted stock units.
F3 The restricted stock units shall vest and be delivered on the first anniversary of November 17, 2025.
F4 Each restricted stock unit represents a contingent right to receive one share of AMTM common stock.
F5 The restricted stock units awarded vested on November 17, 2025.