Amentum Holdings, Inc.
AMTM- Exchange
- NYSE
- Industry
- Services-Business Services, NEC
- SEC CIK
- 0002011286
No open-market purchases or sales by Amentum Holdings, Inc. insiders were filed in the last 90 days; 464 institutions reported holding it in 13F filings for Q2 2026, worth $4.34B in total; Soros Fund Management is the only superinvestor holding it.
13F holders, Q3 2025
Institutional positions in Amentum Holdings, Inc. as of Sep 30, 2025. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 462
- +7 vs. Q2 2025
- Shares held
- 193.4M
- −4.76M (−2.4%) vs. Q2 2025
- Total value
- $4.63B
- −$48.2M (−1.0%) vs. Q2 2025
- New holders
- 76
- 104 more added
- Sold out
- 69
- 179 more reduced
6 institutions that held it in Q2 2025 haven't filed for Q3 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q2 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting AMTM on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 464 | $4.34B |
| Q1 2026 | 486 | $5.28B |
| Q4 2025 | 483 | $5.64B |
| Q3 2025 | 462 | $4.63B |
| Q2 2025 | 461 | $4.73B |
| Q1 2025 | 418 | $3.49B |
| Q4 2024 | 451 | $3.48B |
| Q3 2024 | 492 | $3.23B |
| Q2 2024 | 0 | $0 |
| Q1 2024 | 0 | $0 |
| Q4 2023 | 0 | $0 |
| Q3 2023 | 0 | $0 |
| Q2 2023 | 0 | $0 |
| Q1 2023 | 0 | $0 |
| Q4 2022 | 0 | $0 |
| Q3 2022 | 0 | $0 |
| Q2 2022 | 0 | $0 |
| Q1 2022 | 0 | $0 |
| Q4 2021 | 0 | $0 |
| Q3 2021 | 0 | $0 |
| Q2 2021 | 0 | $0 |
| Q1 2021 | 0 | $0 |
Institutions, Q3 2025
Shares, value and share of portfolio for each institution holding Amentum Holdings, Inc.; share changes are against Q2 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Hotchkis & Wiley Capital Management LLC | 268,130 | $6.42M | 0.02% | +268,130 | New |
| UBS Asset Management Americas Inc | 277,897 | $6.66M | 0.00% | −152,645−35.5% | Reduced |
| Grizzlyrock Capital, LLC | 283,113 | $6.78M | 5.27% | +29,750+11.7% | Added |
| Russell Investments Group, Ltd. | 289,549 | $6.93M | 0.01% | −38,633−11.8% | Reduced |
| Rhumbline Advisers | 289,818 | $6.94M | 0.01% | +2,571+0.9% | Added |
| Jane Street Group, LLC | 301,261 | $7.22M | 0.01% | +301,261 | New |
| Swiss National Bank | 306,491 | $7.34M | 0.00% | +4,300+1.4% | Added |
| CenterBook Partners LP | 308,081 | $7.38M | 0.36% | +182,741+145.8% | Added |
| Comerica Bank | 312,639 | $7.49M | 0.03% | −49,223−13.6% | Reduced |
| Ameriprise Financial Inc | 355,946 | $8.52M | 0.00% | +13,084+3.8% | Added |
| Legal & General Group Plc | 388,289 | $9.30M | 0.00% | −16,384−4.0% | Reduced |
| Two Sigma Investments, LP | 399,123 | $9.56M | 0.01% | +385,394+2,807.2% | Added |
| Moore Capital Management, LP | 407,417 | $9.76M | 0.19% | −203,706−33.3% | Reduced |
| Aristotle Capital Boston, LLC | 409,143 | $9.80M | 0.51% | −13,833−3.3% | Reduced |
| Segra Capital Management, LLC | 417,025 | $9.99M | 11.55% | +417,025 | New |
| Hyperion Capital Advisors LP | 420,008 | $10.1M | 5.38% | +368,521+715.8% | Added |
| Ci Investments Inc. | 428,271 | $10.3M | 0.04% | −26,151−5.8% | Reduced |
| Royce & Associates LP | 454,500 | $10.9M | 0.11% | +119,500+35.7% | Added |
| Vident Advisory, LLC | 454,704 | $10.9M | 0.11% | +22,539+5.2% | Added |
| BW Gestao de Investimentos Ltda. | 511,477 | $12.2M | 0.93% | −203,588−28.5% | Reduced |
| Public Sector Pension Investment Board | 597,976 | $14.3M | 0.05% | +83,804+16.3% | Added |
| Voss Capital, LLC | 625,000 | $15.0M | 0.86% | −775,000−55.4% | Reduced |
| Millennium Management LLC | 640,799 | $15.3M | 0.01% | −4,025,416−86.3% | Reduced |
| New York State Common Retirement Fund | 659,080 | $15.8M | 0.02% | −34,697−5.0% | Reduced |
| Principal Financial Group Inc | 735,755 | $17.6M | 0.01% | −8,762−1.2% | Reduced |
| Nuveen, LLC | 751,304 | $18.0M | 0.00% | +234,730+45.4% | Added |
| Van Eck Associates Corp | 765,677 | $18.3M | 0.02% | −2,302,481−75.0% | Reduced |
| Bank of America Corp | 798,437 | $19.1M | 0.00% | −69,828−8.0% | Reduced |
| Cacti Asset Management LLC | 857,092 | $19.3M | 1.31% | +8,146+1.0% | Added |
| Goldman Sachs Group Inc | 811,931 | $19.4M | 0.00% | +573,684+240.8% | Added |
| Avenir Corp | 862,453 | $20.7M | 2.15% | −32,899−3.7% | Reduced |
| Bank of New York Mellon Corp | 866,263 | $20.7M | 0.00% | −1,943−0.2% | Reduced |
| Northern Trust Corp | 942,945 | $22.6M | 0.00% | +1,912+0.2% | Added |
| Penn Capital Management Co Inc | 960,607 | $23.1M | 1.77% | −42,865−4.3% | Reduced |
| Loomis Sayles & Co L P | 1,064,079 | $25.5M | 0.03% | +4,870+0.5% | Added |
| Voya Investment Management LLC | 1,084,969 | $26.0M | 0.03% | +433,397+66.5% | Added |
| Verition Fund Management LLC | 1,135,626 | $27.2M | 0.16% | +1,043,145+1,128.0% | Added |
| Discovery Capital Management, LLC | 1,139,112 | $27.3M | 1.50% | −1,160,018−50.5% | Reduced |
| Brightline Capital Management, LLC | 1,200,000 | $28.7M | 11.78% | +200,000+20.0% | Added |
| 683 Capital Management, LLC | 1,275,000 | $30.5M | 2.77% | −355,000−21.8% | Reduced |
| Dimensional Fund Advisors LP | 1,306,051 | $31.3M | 0.01% | −28,701−2.2% | Reduced |
| Point72 Asset Management, L.P. | 1,380,992 | $33.1M | 0.07% | +1,030,364+293.9% | Added |
| FIL Ltd | 1,559,024 | $37.3M | 0.03% | −508,181−24.6% | Reduced |
| Arvin Capital Management LP | 1,636,492 | $39.2M | 9.07% | −502,942−23.5% | Reduced |
| Thrivent Financial for Lutherans | 1,805,411 | $43.2M | 0.09% | +118,306+7.0% | Added |
| Morgan Stanley | 1,806,417 | $43.3M | 0.00% | −370,805−17.0% | Reduced |
| Charles Schwab Investment Management Inc | 1,842,171 | $44.1M | 0.01% | +97,158+5.6% | Added |
| Freestone Grove Partners LP | 2,051,859 | $49.1M | 0.37% | 00.0% | Unchanged |
| Mirae Asset Global ETFs Holdings Ltd. | 2,081,611 | $49.9M | 0.08% | +701,859+50.9% | Added |
| Ruane, Cunniff & Goldfarb L.P. | 2,423,748 | $58.0M | 0.96% | −17,995−0.7% | Reduced |
| Geode Capital Management, LLC | 2,654,184 | $63.6M | 0.00% | +141,023+5.6% | Added |
| Thompson Siegel & Walmsley LLC | 2,730,298 | $65.4M | 1.06% | −56,615−2.0% | Reduced |
| Kovitz Investment Group Partners, LLC | 3,007,750 | $72.0M | 0.28% | +7,080+0.2% | Added |
| Frontier Capital Management Co LLC | 5,202,680 | $124.6M | 1.12% | −258,063−4.7% | Reduced |
| FMR LLC | 6,235,249 | $149.3M | 0.01% | +1,661,319+36.3% | Added |
| State Street Corp | 6,833,376 | $163.7M | 0.01% | −244,873−3.5% | Reduced |
| Primecap Management Co | 11,918,586 | $285.5M | 0.22% | −112,070−0.9% | Reduced |
| Vanguard Group Inc | 15,554,691 | $372.5M | 0.01% | −979,134−5.9% | Reduced |
| BlackRock, Inc. | 17,990,449 | $430.9M | 0.01% | −1,004,634−5.3% | Reduced |
| Invesco Ltd. | 22,116,835 | $529.7M | 0.08% | +2,539,594+13.0% | Added |
| American Securities LLC | 45,026,743 | $1.08B | 100.00% | 00.0% | Unchanged |
| Franklin Resources Inc | 9,035 | – | – | +9,035 | New |
| Kopernik Global Investors, LLC | 0 | $0 | 0.00% | −636,226−100.0% | Sold out |
| Engine Capital Management, LP | 0 | $0 | 0.00% | −635,255−100.0% | Sold out |
| Loews Corp | 0 | $0 | 0.00% | −470,000−100.0% | Sold out |
| Arosa Capital Management LP | 0 | $0 | 0.00% | −252,500−100.0% | Sold out |
| Y-Intercept (Hong Kong) Ltd | 0 | $0 | 0.00% | −198,726−100.0% | Sold out |
| Nomura Holdings Inc | 0 | $0 | 0.00% | −108,212−100.0% | Sold out |
| RFG Advisory, LLC | 0 | $0 | 0.00% | −102,171−100.0% | Sold out |
| Marshall Wace, LLP | 0 | $0 | 0.00% | −74,831−100.0% | Sold out |
| Marex Group plc | 0 | $0 | 0.00% | −50,000−100.0% | Sold out |
| Fortress Investment Group LLC | 0 | $0 | 0.00% | −38,106−100.0% | Sold out |
| Highland Capital Management Fund Advisors, L.P. | 0 | $0 | 0.00% | −35,263−100.0% | Sold out |
| Oak Thistle LLC | 0 | $0 | 0.00% | −28,230−100.0% | Sold out |
| Proficio Capital Partners LLC | 0 | $0 | 0.00% | −26,031−100.0% | Sold out |
| Marco Investment Management LLC | 0 | $0 | 0.00% | −25,157−100.0% | Sold out |
| Wesbanco Bank Inc | 0 | $0 | 0.00% | −24,466−100.0% | Sold out |
| Sandia Investment Management LP | 0 | $0 | 0.00% | −22,505−100.0% | Sold out |
| Phoenix Holdings Ltd. | 0 | $0 | 0.00% | −18,932−100.0% | Sold out |
| Axq Capital, LP | 0 | $0 | 0.00% | −15,609−100.0% | Sold out |
| Rock Creek Group, LP | 0 | $0 | 0.00% | −15,000−100.0% | Sold out |
| Aristeia Capital LLC | 0 | $0 | 0.00% | −13,568−100.0% | Sold out |
| Worldquant Millennium Advisors LLC | 0 | $0 | 0.00% | −13,358−100.0% | Sold out |
| Whalen Wealth Management Inc. | 0 | $0 | 0.00% | −11,616−100.0% | Sold out |
| United Capital Financial Advisers, LLC | 0 | $0 | 0.00% | −11,228−100.0% | Sold out |
| Mesirow Financial Investment Management, Inc. | 0 | $0 | 0.00% | −10,515−100.0% | Sold out |
| Diametric Capital, LP | 0 | $0 | 0.00% | −10,343−100.0% | Sold out |
| Everett Harris & Co | 0 | $0 | 0.00% | −10,085−100.0% | Sold out |
| Janney Montgomery Scott LLC | 0 | $0 | 0.00% | −10,014−100.0% | Sold out |
| Lingohr & Partner Asset Management GmbH | 0 | $0 | 0.00% | −10,000−100.0% | Sold out |
| Kentucky Retirement Systems | 0 | $0 | 0.00% | −9,971−100.0% | Sold out |
| Utah Retirement Systems | 0 | $0 | 0.00% | −9,183−100.0% | Sold out |
| Cantor Fitzgerald, L. P. | 0 | $0 | 0.00% | −9,087−100.0% | Sold out |
| Ethic Inc. | 0 | $0 | 0.00% | −9,149−100.0% | Sold out |
| Intact Investment Management Inc. | 0 | $0 | 0.00% | −7,319−100.0% | Sold out |
| American National Bank | 0 | $0 | 0.00% | −6,788−100.0% | Sold out |
| Glenmede Investment Management, LP | 0 | $0 | 0.00% | −4,325−100.0% | Sold out |
| Caldwell Trust Co | 0 | $0 | 0.00% | −1,954−100.0% | Sold out |
| Riggs Asset Managment Co. Inc. | 0 | $0 | 0.00% | −1,931−100.0% | Sold out |
| Ofi Invest Asset Management | 0 | $0 | 0.00% | −2,051−100.0% | Sold out |