[Form 4/A] Amentum Holdings, Inc. Amended Insider Trading Activity

Rhea-AI Filing Summary

Amentum Holdings, Inc. reports updated insider holdings for a director and executive chair on an amended Form 4. The insider is shown as beneficially owning 837,668 shares of Amentum common stock directly and 23,550 shares indirectly through a spouse. A footnote explains that the amounts reflect a non-reportable transfer arising from a pro-rata in-kind distribution of shares by Jacobs Solutions Inc. to its shareholders for no consideration on May 30, 2025, rather than an open-market trade or other purchase or sale.

Insider Trade Summary

2 transactions reported

Mixed 2 txns

Insider DEMETRIOU STEVEN J.

Role Executive Chair

Type	Security	Shares	Price	Value
holding	Common Stock	--	--	--
holding	Common Stock	--	--	--

Holdings After Transaction: Common Stock — 837,668 shares (Direct); Common Stock — 23,550 shares (Indirect, By Spouse)

Footnotes (1)

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Form 4 Insider Transactions: What Each Field Means →

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

DEMETRIOU STEVEN J.

(Last) (First) (Middle)

C/O AMENTUM HOLDINGS, INC.

4800 WESTFIELDS BOULEVARD, SUITE 400

(Street)

CHANTILLY VA 20151

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
Amentum Holdings, Inc. [ AMTM ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Executive Chair

3. Date of Earliest Transaction (Month/Day/Year)
11/06/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)
11/10/2025

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock								837,668(1)	D
Common Stock								23,550	I	By Spouse

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. Reflects a non-reportable transaction for shares transferred from the pro-rata distribution in-kind by Jacobs Solutions Inc. to its shareholders for no consideration on May 30, 2025.

Remarks:

	/s/ Indira Lall, Attorney-in-fact	02/10/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

How many Amentum (AMTM) shares are beneficially owned according to this Form 4/A?

The insider is reported as beneficially owning 837,668 Amentum common shares directly and an additional 23,550 shares indirectly through a spouse. These figures summarize the director and executive chair’s reported holdings after the referenced non-reportable transfer.

What is the nature of the indirect ownership reported in the Amentum (AMTM) Form 4/A?

The Form 4/A lists 23,550 Amentum common shares as indirectly owned, with the nature of indirect beneficial ownership described as “By Spouse.” This indicates the shares are held by the spouse but counted toward the reporting person’s beneficial ownership.

What transaction explanation is provided in this Amentum (AMTM) Form 4/A filing?

The explanation states the reported holdings reflect a non-reportable transfer from a pro-rata in-kind distribution by Jacobs Solutions Inc. to its shareholders for no consideration on May 30, 2025. This clarifies the change arose from a distribution, not a conventional trade.

What roles does the reporting person hold at Amentum (AMTM) in this Form 4/A?

The reporting person is identified as both a Director and an Officer of Amentum Holdings, Inc., with the specific officer title disclosed as Executive Chair. These roles explain why their beneficial ownership in Amentum common stock must be reported.

What type of SEC document is this for Amentum (AMTM), and what does it amend?

This is an amended Form 4/A, which updates a prior Form 4 insider ownership report. It revises the disclosure of the director and executive chair’s Amentum common stock holdings, incorporating the explanation of the non-reportable distribution-related transfer.

Does this Amentum (AMTM) Form 4/A describe derivative securities positions?

The filing includes a standard table for derivative securities but does not list specific derivative transactions or holdings in the provided excerpt. Instead, the detailed disclosure focuses on non-derivative Amentum common stock beneficially owned directly and indirectly.