# Amentum Holdings, Inc. Common Stock

Amentum Holdings, Inc. Common Stock is a security (CUSIP 023939101) tracked across SEC portfolio filings. 501 institutional managers reported $4.7B on Form 13F as of 2026-06-30; 31 registered fund positions totaling $360.6M via N-PORT as of 2026-05-31.

## Summary

- Issuer: Amentum Holdings, Inc.
- Class: Common Stock
- CUSIP: 023939101
- Asset category: EC
- 13F holders: 501
- 13F value: $4.7B
- 13F period: 2026-06-30
- N-PORT fund positions: 31
- N-PORT value: $360.6M
- N-PORT report: 2026-05-31

## Top institutional holders (Form 13F)

_Showing 15 of 501 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| [AMERICAN SECURITIES LLC](https://search.stillhousedata.com/firm/160648) | NEW YORK, NY | $1.2B | 45,026,743 |
| BlackRock, Inc. | New York, NY | $465.3M | 17,841,283 |
| [VANGUARD GROUP INC](https://search.stillhousedata.com/firm/105958) | Valley Forge, PA | $446.9M | 15,411,745 |
| [PRIMECAP MANAGEMENT CO/CA/](https://search.stillhousedata.com/firm/105516) | PASADENA, CA | $315.2M | 12,085,294 |
| FMR LLC | BOSTON, MA | $145.5M | 5,578,386 |
| STATE STREET CORP | BOSTON, MA | $132.5M | 5,079,041 |
| [FRONTIER CAPITAL MANAGEMENT CO LLC](https://search.stillhousedata.com/firm/106274) | Boston, MA | $128.6M | 4,930,210 |
| DIMENSIONAL FUND ADVISORS LP | AUSTIN, TX | $98.8M | 3,787,420 |
| Arvin Capital Management LP | AUSTIN, TX | $73.5M | 2,071,200 |
| [GEODE CAPITAL MANAGEMENT, LLC](https://search.stillhousedata.com/firm/115504) | BOSTON, MA | $73.4M | 2,814,415 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | CENTRAL, K3 | $72.6M | 2,785,134 |
| [Focus Partners Wealth](https://search.stillhousedata.com/firm/159289) | ST LOUIS, MO | $67.9M | 2,604,911 |
| BANK OF AMERICA CORP /DE/ | CHARLOTTE, NC | $62.7M | 2,405,041 |
| MORGAN STANLEY | NEW YORK, NY | $58.3M | 2,234,913 |
| [CHARLES SCHWAB INVESTMENT MANAGEMENT INC](https://search.stillhousedata.com/firm/106753) | SAN FRANCISCO, CA | $53.9M | 2,067,930 |

## Top fund holders (N-PORT)

_Showing 15 of 31 fund positions by value._

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [VANGUARD PRIMECAP CORE FUND](https://search.stillhousedata.com/fund/S000002581) | VANGUARD FENWAY FUNDS | $137.4M | 101.47% |
| [Invesco Small Cap Value Fund](https://search.stillhousedata.com/fund/S000027837) | AIM Sector Funds (Invesco Sector Funds) | $110.9M | 103.10% |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $44.7M | 5.49% |
| [Sequoia Fund Inc](https://search.stillhousedata.com/fund/S000012155) | Sequoia Fund Inc | $20.0M | 60.09% |
| [PRIMECAP Odyssey Growth Fund](https://search.stillhousedata.com/fund/S000005540) | PRIMECAP Odyssey Funds | $15.3M | 28.18% |
| [Ancora/Thelen Small-Mid Cap Fund](https://search.stillhousedata.com/fund/S000039307) | ANCORA TRUST | $12.0M | 564.00% |
| [Large Cap Index Master Portfolio](https://search.stillhousedata.com/fund/S000033023) | Master Investment Portfolio | $2.3M | 0.64% |
| [Nuveen Small/Mid Cap Value Fund](https://search.stillhousedata.com/fund/S000014609) | Nuveen Investment Trust | $2.3M | 205.77% |
| [VANGUARD BALANCED INDEX FUND](https://search.stillhousedata.com/fund/S000002560) | VANGUARD VALLEY FORGE FUNDS | $2.1M | 0.36% |
| [BNY Mellon Smallcap Stock Index Fund](https://search.stillhousedata.com/fund/S000000132) | BNY MELLON INDEX FUNDS, INC. | $2.0M | 23.71% |
| [VANGUARD INSTITUTIONAL TOTAL STOCK MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002855) | VANGUARD INSTITUTIONAL INDEX FUNDS | $1.8M | 0.61% |
| [NORTH SQUARE SMALL CAP VALUE FUND](https://search.stillhousedata.com/fund/S000091143) | Valued Advisers Trust | $1.6M | 76.81% |
| Gabelli Equity Trust Inc | Gabelli Equity Trust Inc | $1.5M | 8.58% |
| [AMG Frontier Small Cap Growth Fund](https://search.stillhousedata.com/fund/S000009910) | AMG Funds I | $1.3M | 136.57% |
| [The Gabelli Asset Fund](https://search.stillhousedata.com/fund/S000001087) | Gabelli Asset Fund | $1.3M | 8.31% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/023939101.md)
- [Search all SEC filings, advisers and people on Adviser Search](https://search.stillhousedata.com/)

---

Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.