Sean Thomas Mullen - Nov 6, 2025 Form 4 Insider Report for Amentum Holdings, Inc. (AMTM)

Role
Chief Growth Officer
Signature
/s/ Mark Esposito, Attorney-in-Fact
Stock symbol
AMTM
Transactions as of
Nov 6, 2025
Transactions value $
-$35,322
Form type
4
Date filed
11/10/2025, 04:44 PM
Previous filing
Dec 23, 2024
Next filing
Nov 19, 2025
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Mullen Sean Thomas Chief Growth Officer C/O AMENTUM HOLDINGS, INC., 4800 WESTFIELDS BOULEVARD, SUITE 400, CHANTILLY /s/ Mark Esposito, Attorney-in-Fact 2025-11-10 0002034388

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction AMTM Common Stock Options Exercise +4.84K 4.84K Nov 6, 2025 Direct F1
transaction AMTM Common Stock Tax liability -$35.3K -1.62K -33.51% $21.79 3.22K Nov 6, 2025 Direct F2

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 -4.84K -33.33% $0.00 9.68K Nov 6, 2025 Common Stock 4.84K Direct F1, F3, F4
* 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 Each restricted stock unit represents a contingent right to receive one share of AMTM common stock.
F4 The restricted stock units awarded vested on November 6, 2025.