Amentum Holdings, Inc. - Director's Dealing 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: Amentum Holdings, Inc. (AMTM)
CIK: 0002011286
Period of Report: 2025-11-06

Reporting Person: Heller John E. (Director, Chief Executive Officer)

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-11-06	Common Stock	M	39617	—	Acquired	131411	Direct
2025-11-06	Common Stock	F	17868	$21.79	Disposed	113543	Direct

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-11-06	Restricted Stock Units	$	M	39617	Disposed		Common Stock (39617)	Direct

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.