| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| ASP Manager Corp. | 18% | $974,005,730 | 43,893,904 | ASP Manager Corp. | 17 Dec 2024 | |||
| GOLDBERG ALAN E | 18% | $974,005,730 | 43,893,904 | Alan E. Goldberg | 17 Dec 2024 | |||
| Invesco Ltd. | 9.1% | +29% | $529,698,198 | +$117,971,114 | 22,116,835 | +29% | Invesco Ltd. | 30 Sep 2025 |
| BlackRock, Inc. | 6.9% | $372,220,408 | 16,774,241 | BlackRock, Inc. | 31 Dec 2024 | |||
| VANGUARD GROUP INC | 6.8% | $367,076,899 | 16,542,447 | The Vanguard Group | 31 Dec 2024 |
As of 31 Dec 2025, 470 institutional investors reported holding 193,912,627 shares of Amentum Holdings, Inc. - Common Stock (AMTM). This represents 80% of the company’s total 243,042,143 outstanding shares.
The largest institutional shareholders of Amentum Holdings, Inc. - Common Stock (AMTM) together control 66% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| AMERICAN SECURITIES LLC | 19% | 45,026,743 | 0% | 100% | $1,305,775,547 |
| Invesco Ltd. | 9% | 21,834,003 | -1.3% | 0.1% | $633,186,097 |
| BlackRock, Inc. | 7.2% | 17,459,099 | -3% | 0.01% | $506,313,859 |
| VANGUARD GROUP INC | 6.3% | 15,411,745 | -0.92% | 0.01% | $446,940,605 |
| PRIMECAP MANAGEMENT CO/CA/ | 5% | 12,126,927 | +1.7% | 0.27% | $351,680,883 |
| FMR LLC | 2.8% | 6,707,304 | +7.6% | 0.01% | $194,511,815 |
| FRONTIER CAPITAL MANAGEMENT CO LLC | 2.4% | 5,772,976 | +11% | 1.8% | $167,416,293 |
| STATE STREET CORP | 2.1% | 5,061,620 | -26% | 0% | $146,786,980 |
| Focus Partners Wealth | 1.1% | 2,794,417 | +8468% | 0.09% | $81,038,102 |
| GEODE CAPITAL MANAGEMENT, LLC | 1.1% | 2,659,364 | +0.2% | 0% | $77,145,389 |
| Ruane, Cunniff & Goldfarb L.P. | 0.99% | 2,394,129 | -1.2% | 1.1% | $69,429,741 |
| NORGES BANK | 0.94% | 2,294,097 | 0.01% | $66,528,813 | |
| MORGAN STANLEY | 0.85% | 2,075,352 | +15% | 0% | $60,185,252 |
| Thrivent Financial for Lutherans | 0.85% | 2,069,104 | +15% | 0.11% | $60,004,000 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | 0.81% | 1,961,927 | -5.7% | 0.09% | $56,895,904 |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | 0.8% | 1,952,002 | +6% | 0.01% | $56,608,065 |
| THOMPSON SIEGEL & WALMSLEY LLC | 0.79% | 1,921,809 | -30% | 0.94% | $55,732,000 |
| DIMENSIONAL FUND ADVISORS LP | 0.75% | 1,832,926 | +40% | 0.01% | $53,156,787 |
| Arvin Capital Management LP | 0.67% | 1,636,492 | 0% | 10% | $47,458,268 |
| COOPER CREEK PARTNERS MANAGEMENT LLC | 0.64% | 1,553,074 | 2.1% | $45,039,000 | |
| AQR CAPITAL MANAGEMENT LLC | 0.6% | 1,452,049 | +779% | 0.02% | $42,109,421 |
| FIL Ltd | 0.59% | 1,429,384 | -8.3% | 0.03% | $41,452,136 |
| BRIGHTLINE CAPITAL MANAGEMENT, LLC | 0.57% | 1,392,000 | +16% | 16% | $40,368,000 |
| ExodusPoint Capital Management, LP | 0.49% | 1,184,186 | +1015% | 0.38% | $34,341,394 |
| BANK OF AMERICA CORP /DE/ | 0.48% | 1,157,427 | +45% | 0% | $33,565,383 |
| Period | Reported Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2025 Q4 | 193,912,627 | $5,624,733,468 | +$52,603,559 | $29.00 | 470 |
| 2025 Q3 | 193,408,261 | $4,630,898,069 | -$164,115,779 | $23.95 | 458 |
| 2025 Q2 | 200,286,307 | $4,728,932,149 | +$283,438,102 | $23.61 | 449 |
| 2025 Q1 | 189,918,108 | $3,456,762,603 | +$424,243,410 | $18.20 | 410 |
| 2024 Q4 | 180,057,223 | $3,789,816,275 | +$1,468,894,480 | $21.03 | 445 |
| 2024 Q3 | 99,712,565 | $3,204,357,186 | +$2,913,258,016 | $32.25 | 480 |