# EDGAR Filing Document

**Accession Number:** 0001778333
**File Stem:** 0001628280-26-006828
**Filing Date:** 2026-2
**Character Count:** 10559
**Document Hash:** 5c830544f5bdd9d04bd64e3ec3cb420f
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001628280-26-006828.hdr.sgml**: 20260210

**ACCESSION NUMBER**: 0001628280-26-006828

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 4

**CONFORMED PERIOD OF REPORT**: 20260206

**FILED AS OF DATE**: 20260210

**DATE AS OF CHANGE**: 20260210

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Loughran Barbara
- **CENTRAL INDEX KEY:** 0001778333

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-42176
- **FILM NUMBER:** 26615991

**MAIL ADDRESS:**
- **STREET 1:** 2500 COLUMBIA AVENUE
- **CITY:** LANCASTER
- **STATE:** PA
- **ZIP:** 17603
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Amentum Holdings, Inc.
- **CENTRAL INDEX KEY:** 0002011286
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-BUSINESS SERVICES, NEC [7389]
- **ORGANIZATION NAME:** 07 Trade & Services
- **EIN:** 990622272
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1002

**BUSINESS ADDRESS:**
- **STREET 1:** 4800 WESTFIELDS BOULEVARD
- **STREET 2:** SUITE 400
- **CITY:** CHANTILLY
- **STATE:** VA
- **ZIP:** 20151
- **BUSINESS PHONE:** 7035790410

**MAIL ADDRESS:**
- **STREET 1:** 4800 WESTFIELDS BOULEVARD
- **STREET 2:** SUITE 400
- **CITY:** CHANTILLY
- **STATE:** VA
- **ZIP:** 20151

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** Amazon Holdco Inc.
- **DATE OF NAME CHANGE:** 20240208

## Ex-24

![](amtm-powerofattorneytoam001.jpg)

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;POWER OF ATTORNEY Know all by these presents, that the undersigned hereby constitutes and appoints Michele T. St. Mary, Indira Lall, and Mark Esposito, that such person signing individually, as the undersigned's true and lawful attorneys-in-fact, solely in connection with the undersigned's ownership, acquisition or disposition of common stock of Amentum Holdings, Inc., to: (1) execute for and on behalf of the undersigned any filings related to the undersigned's ownership, acquisition or disposition solely of common stock of Amentum Holdings, Inc. on Schedule 13D or Forms 3, 4, 5 or 144 in accordance with Sections 13(d) and 16(a) of the Securities Exchange Act of 1934 and the rules and regulations thereunder and Rule 144 of the Securities Act of 1933; (2) do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete and execute any such filings on Schedule 13D or Forms 3, 4, 5 or 144, or other form or report, or any amendment or amendments thereto, and timely file such form with the SEC solely in connection with the undersigned's ownership, acquisition or disposition of common stock of Amentum Holdings, Inc.; and (3) take any other action of any type in connection with the foregoing which, in the opinion of such attorneys-in-fact, may be of benefit to, in the best interest of, or legally required by, the undersigned, solely in connection with the undersigned's ownership, acquisition or disposition of Amentum Holdings, Inc., it being understood that the documents executed by such attorneys-in-fact on behalf of the undersigned pursuant to this Power of Attorney shall be in such form and shall contain such terms and conditions as such attorneys-in-fact may approve in such attorneys-in-fact's discretion. The undersigned hereby grants to such attorneys-in-fact, any such person signing individually, solely in connection with the undersigned's ownership, acquisition or disposition of common stock of Amentum Holdings, Inc., full power and authority to do and perform any and every act and thing requisite, necessary, or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, hereby ratifying and confirming that all such attorneys-in-fact, shall lawfully do or cause to be done by virtue of this Power of Attorney and the rights and powers herein granted. The undersigned acknowledges that none of the foregoing attorneys-in-fact, in serving in such capacity at the request of the undersigned, is assuming any of the undersigned's responsibilities to comply with Sections 13(d) or 16(a) of the Securities Exchange Act of 1934, Rule 144 of the Securities Act of 1933 or any other rule or regulation of the SEC. With respect to the internal relationship between the undersigned and each attorney-in-fact, the undersigned undertakes to indemnify and hold harmless each attorney-in-fact from and against all costs, expenses, claims, obligations, any damage and any liability of whatever kind incurred by, or asserted against, such attorney-in- fact under or in connection with the agreed upon exercise of any rights granted under this Power of Attorney. This Power of Attorney shall remain in full force and effect until the undersigned is no longer required to file Schedule 13D or Forms 3, 4, 5 and 144 with respect to the undersigned's holdings of and transactions in Amentum Holdings, Inc., unless earlier revoked by the undersigned in a signed writing delivered to the foregoing attorneys-in-fact. [signature page follows]

------

![](amtm-powerofattorneytoam002.jpg)

[Signature Page to Power of Attorney] IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be executed as of this 22nd day of January, 2026. Barbara L. Loughran Signature: /s/ Barbara L. Loughran Print Name: Barbara L. Loughran Title: Director

------

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

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] 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**<sup>*</sup><br>Loughran Barbara<br><sub>(Last) (First) (Middle)</sub><br>C/O AMENTUM HOLDINGS, INC.<br>4800 WESTFIELDS BOULEVARD, SUITE 400<br><sub>(Street)</sub><br>CHANTILLY, VA 20151<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-02-06 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [ ] 10% Owner<br>[ ] Officer (give title below) [ ] Other (specify below)<br>_ _ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Amentum Holdings, Inc. [ AMTM ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2026-02-06 |  | A |  | 5062<sup>(1)</sup> | A | $0 | 9662 | D |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

---

### Footnotes:

(1) The restricted stock units shall vest on the date of the next annual meeting of stockholders of the Issuer.

**Signature:** /s/ Indira Lall, Attorney-in-fact  
**Date:** 2026-02-10

### Remarks:

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.**