AMENTUM HOLDINGS INC AMTM
COM · Common Stock · CUSIP 023939101 · ISIN US0239391016
American energy and defense projects contractor
- SectorIndustrials
- IndustryServices-Business Services, NEC
- HeadquartersChantilly, VA
- Founded2020
- Websiteamentum.com
- FilingsSEC EDGAR
* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($4.4m this quarter). Holder counts are more reliable. Shares outstanding: 244.3m as of 2026-05-08, from the company's own SEC filing; the percentage can still exceed 100%: lent-out shares are counted by the lender and the buyer, and some reports overlap without saying so. Implied quarter-end price ≈ $25.00. Options: 19 managers hold calls ($134.1m notional), 15 hold puts ($43.0m).
Trends to Q1 2026
Institutional holders
Managers reporting a position, each quarter
Numbers
| Quarter | Holders |
|---|---|
| Q3 2024 | 493 |
| Q4 2024 | 452 |
| Q1 2025 | 420 |
| Q2 2025 | 462 |
| Q3 2025 | 462 |
| Q4 2025 | 483 |
| Q1 2026 | 486 |
Buyers vs sellers
Managers adding to or starting a position, vs cutting or selling out
Numbers
| Quarter | Bought or added | Cut or sold out |
|---|---|---|
| Q4 2024 | 209 | 340 |
| Q1 2025 | 179 | 245 |
| Q2 2025 | 338 | 163 |
| Q3 2025 | 178 | 248 |
| Q4 2025 | 198 | 215 |
| Q1 2026 | 212 | 210 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q2 2025 | $57.6m | $31.4m | 0.54 |
| Q3 2025 | $22.9m | $15.4m | 0.67 |
| Q4 2025 | $85.8m | $30.3m | 0.35 |
| Q1 2026 | $134.1m | $43.0m | 0.32 |
Biggest buyers
| DIMENSIONAL FUND ADVISORS LP | Added | +2.0m |
| Permian Investment Partners, LP | New | +1.6m |
| TORONTO DOMINION BANK | New | +1.6m |
| UBS Group AG | Added | +1.5m |
| BANK OF AMERICA CORP /DE/ | Added | +1.2m |
| SEGRA CAPITAL MANAGEMENT, LLC | Added | +1.0m |
| Troluce Capital Advisors LLC | New | +1.0m |
| Point72 Asset Management, L.P. | Added | +935.3k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | Added | +823.2k |
| MILLENNIUM MANAGEMENT LLC | Added | +569.9k |
Biggest sellers
| ExodusPoint Capital Management, LP | Sold out | -1.2m |
| FMR LLC | Reduced | -1.1m |
| AQR CAPITAL MANAGEMENT LLC | Reduced | -944.2k |
| FRONTIER CAPITAL MANAGEMENT CO LLC | Reduced | -842.8k |
| FIL Ltd | Reduced | -777.2k |
| Ruane, Cunniff & Goldfarb L.P. | Reduced | -771.1k |
| Legacy Advisors, LLC | Reduced | -750.0k |
| COOPER CREEK PARTNERS MANAGEMENT LLC | Reduced | -623.7k |
| THOMPSON SIEGEL & WALMSLEY LLC | Reduced | -395.9k |
| Invesco Ltd. | Reduced | -360.2k |
Biggest calls
| COOPER CREEK PARTNERS MANAGEMENT LLC | New | $40.7m1.6m shares |
| Caption Management, LLC | Added | $25.1m961.1k shares |
| Arvin Capital Management LP | Added | $15.6m596.5k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $13.1m503.8k shares |
| CITADEL ADVISORS LLC | Reduced | $6.4m244.0k shares |
| Twin Tree Management, LP | Added | $5.7m218.1k shares |
| SEGRA CAPITAL MANAGEMENT, LLC | New | $5.2m200.0k shares |
| GROUP ONE TRADING LLC | Added | $4.4m167.0k shares |
| JANE STREET GROUP, LLC | Added | $3.6m139.3k shares |
| Walleye Trading LLC | Added | $2.7m104.3k shares |
Biggest puts
| Caption Management, LLC | Added | $11.7m450.0k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $11.2m428.4k shares |
| CITADEL ADVISORS LLC | Added | $4.8m182.2k shares |
| Arvin Capital Management LP | New | $3.9m150.0k shares |
| Walleye Trading LLC | Added | $2.8m106.3k shares |
| JANE STREET GROUP, LLC | Added | $2.4m90.6k shares |
| NOMURA HOLDINGS INC | Unchanged | $1.2m47.0k shares |
| GROUP ONE TRADING LLC | Added | $1.2m46.0k shares |
| Lido Advisors, LLC | New | $1.1m41.5k shares |
| IMC-Chicago, LLC | Reduced | $972.8k37.3k shares |
Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.
Major shareholders (over 5%)
Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.
| Holder | Stake |
|---|---|
ASP Manager Corp.
13D · may seek influence
new · filed 2024-12-23
Stated purposeThe information set forth or incorporated by reference in Items 3, 5 and 6 is hereby incorporated by reference in this Item 4. Director Nominees Benjamin Dickson, a managing director of American Securities LLC, and Connor Wentzell, a principal of American Securities LLC, are nominees of the Sponsor Stockholders (as defined below) to the Issuer's board of directors (the "Board") pursuant to the Stockholders Agreement (as defined below). Alan Goldberg, the co-founder and chief executive officer of Goldberg Lindsay & Co. LLC, an affiliate of LG (as defined below), and Russell Triedman, a managing partner of Goldberg Lindsay & Co. LLC, are also nominees of the Sponsor Stockholders on the Board pursuant to the Stockholders Agreement. General The Reporting Persons acquired the secur… Full filing |
18.0% |
GOLDBERG ALAN E
13D · may seek influence
new · filed 2024-12-23
Stated purposeThe information set forth or incorporated by reference in Items 3, 5 and 6 is hereby incorporated by reference in this Item 4. Director Nominees Mr. Goldberg, the co-founder and chief executive officer of Goldberg Lindsay & Co. LLC, an affiliate of the Reporting Persons, and Russell Triedman, a managing partner of Goldberg Lindsay & Co. LLC, are nominees of the Sponsor Stockholders (as defined below) to the Issuer's board of directors (the "Board") pursuant to the Stockholders Agreement (as defined below). Benjamin Dickson, a managing director of American Securities LLC, an affiliate of AS (as defined below), and Connor Wentzell, a principal of American Securities LLC, are also nominees of the Sponsor Stockholders on the Board pursuant to the Stockholders Agreement. General The Report… Full filing |
18.0% |
| Invesco Ltd. 13G · institution +1.0 pts · filed 2026-05-07 | 10.1% |
| BlackRock, Inc. 13G · institution filed 2025-02-05 | 6.9% |
| PRIMECAP MANAGEMENT CO/CA/ 13G · institution new · filed 2026-08-06 | 5.0% |
Fell to 5% or below in the last year: VANGUARD GROUP INC (0.0%, 2026-03-26)
Insider purchases and sales in Q1 2026
Shares bought or sold by the company's own officers, directors and 10% owners, in the open market or privately, as they reported to the SEC on Form 4 (due within two business days of the trade). Grants, option exercises, shares withheld for tax and gifts aren't included.
Officers and directors buying vs selling
Number of people, by quarter (10% owners not included)
Numbers
| Quarter | Buying | Bought | Selling | Sold | Sold under a plan |
|---|---|---|---|---|---|
| Q2 2024 | 0 | — | 0 | — | — |
| Q3 2024 | 0 | — | 0 | — | — |
| Q4 2024 | 0 | — | 0 | — | — |
| Q1 2025 | 2 | $2.2m | 0 | — | — |
| Q2 2025 | 0 | — | 0 | — | — |
| Q3 2025 | 0 | — | 0 | — | — |
| Q4 2025 | 0 | — | 0 | — | — |
| Q1 2026 | 0 | — | 0 | — | — |
None reported in Q1 2026.
Holders, Q1 2026
| Manager | Shares | Change |
|---|---|---|
| AMERICAN SECURITIES LLC 29.88% of their portfolio | 45.0m $1.2bn | Unchanged |
| Invesco Ltd. 0.05% of their portfolio | 21.5m $560.0m | Reduced -360.2k |
| BlackRock, Inc. 0.01% of their portfolio | 17.8m $465.3m | Added +382.2k |
| PRIMECAP MANAGEMENT CO/CA/ 0.25% of their portfolio | 12.1m $315.2m | Reduced -41.6k |
| Legacy Advisors, LLC 1.07% of their portfolio | 9.1m $9.1m | Reduced -750.0k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.01% of their portfolio | 7.9m $204.8m | First filing |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 6.7m $173.5m | First filing |
| FMR LLC 0.01% of their portfolio | 5.6m $145.5m | Reduced -1.1m |
| STATE STREET CORP 0.00% of their portfolio | 5.1m $132.5m | Added +17.4k |
| FRONTIER CAPITAL MANAGEMENT CO LLC 1.32% of their portfolio | 4.9m $128.6m | Reduced -842.8k |
| DIMENSIONAL FUND ADVISORS LP 0.02% of their portfolio | 3.8m $98.8m | Added +2.0m |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 2.8m $73.4m | Added +155.1k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.10% of their portfolio | 2.8m $72.6m | Added +823.2k |
| Focus Partners Wealth 0.08% of their portfolio | 2.6m $67.9m | Reduced -189.5k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 2.4m $62.7m | Added +1.2m |
| MORGAN STANLEY 0.00% of their portfolio | 2.2m $58.3m | Added +159.6k |
| Thrivent Financial for Lutherans 0.10% of their portfolio | 2.1m $54.8m | Added +31.4k |
| Arvin Capital Management LP 12.62% of their portfolio | 2.1m $54.0m | Added +434.7k |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio | 2.1m $53.9m | Added +115.9k |
| UBS Group AG 0.01% of their portfolio | 1.7m $44.6m | Added +1.5m |
| Point72 Asset Management, L.P. 0.07% of their portfolio | 1.6m $42.5m | Added +935.3k |
| Ruane, Cunniff & Goldfarb L.P. 0.70% of their portfolio | 1.6m $42.3m | Reduced -771.1k |
| SEGRA CAPITAL MANAGEMENT, LLC 32.74% of their portfolio | 1.6m $42.1m | Added +1.0m |
| Permian Investment Partners, LP 4.52% of their portfolio | 1.6m $40.9m | New |
| TORONTO DOMINION BANK 0.08% of their portfolio | 1.6m $40.8m | New |
| THOMPSON SIEGEL & WALMSLEY LLC 0.70% of their portfolio | 1.5m $39.8m | Reduced -395.9k |
| BRIGHTLINE CAPITAL MANAGEMENT, LLC 10.77% of their portfolio | 1.4m $36.4m | Added +4.0k |
| Verition Fund Management LLC 0.33% of their portfolio | 1.3m $33.9m | Added +432.8k |
| VOYA INVESTMENT MANAGEMENT LLC 0.03% of their portfolio | 1.2m $31.3m | Added +52.0k |
| GOLDMAN SACHS GROUP INC 0.00% of their portfolio | 1.1m $29.5m | Added +487.3k |
| LOOMIS SAYLES & CO L P 0.04% of their portfolio | 1.1m $28.2m | Reduced -37.6k |
| Troluce Capital Advisors LLC 2.76% of their portfolio | 1.0m $26.1m | New |
| NORTHERN TRUST CORP 0.00% of their portfolio | 984.1k $25.7m | Added +31.1k |
| VANGUARD FIDUCIARY TRUST CO 0.01% of their portfolio | 947.5k $24.7m | First filing |
| COOPER CREEK PARTNERS MANAGEMENT LLC 1.17% of their portfolio | 929.3k $24.2m | Reduced -623.7k |
| Bank of New York Mellon Corp 0.00% of their portfolio | 908.6k $23.7m | Reduced -13.5k |
| TWO SIGMA INVESTMENTS, LP 0.02% of their portfolio | 900.2k $23.5m | Added +262.2k |
| CACTI ASSET MANAGEMENT LLC 1.39% of their portfolio | 881.7k $23.0m | Unchanged |
| MOORE CAPITAL MANAGEMENT, LP 0.83% of their portfolio | 873.6k $22.8m | Added +398.3k |
| Nuveen, LLC 0.01% of their portfolio | 871.8k $22.7m | Added +58.0k |
| AVENIR CORP 2.67% of their portfolio | 841.1k $21.9m | Reduced -9.8k |
| 683 Capital Management, LLC 1.87% of their portfolio | 775.0k $20.2m | Reduced -60.0k |
| PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio | 744.7k $19.4m | Added +16.3k |
| Russell Investments Group, Ltd. 0.02% of their portfolio | 713.8k $18.6m | Added +276.8k |
| Ancora Advisors LLC 0.39% of their portfolio | 703.1k $18.3m | Added +300.8k |
| Penn Capital Management Company, LLC 1.41% of their portfolio | 694.4k $18.2m | Reduced -49.6k |
| FIL Ltd 0.01% of their portfolio | 652.2k $17.0m | Reduced -777.2k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 636.7k $16.6m | Added +171.9k |
| MILLENNIUM MANAGEMENT LLC 0.01% of their portfolio | 631.1k $16.5m | Added +569.9k |
| Public Sector Pension Investment Board 0.04% of their portfolio | 549.8k $14.3m | Added +19.2k |
| ROYCE & ASSOCIATES LP 0.14% of their portfolio | 549.8k $14.3m | Added +54.5k |
| VAN ECK ASSOCIATES CORP 0.01% of their portfolio | 547.6k $14.3m | Added +16.6k |
| Gotham Asset Management, LLC 0.04% of their portfolio | 521.0k $13.6m | Reduced -114.4k |
| AQR CAPITAL MANAGEMENT LLC 0.01% of their portfolio | 507.8k $13.2m | Reduced -944.2k |
| NEW YORK STATE COMMON RETIREMENT FUND 0.02% of their portfolio | 502.5k $13.1m | Reduced -32.7k |
| CI INVESTMENTS INC. 0.05% of their portfolio | 420.1k $11.0m | Reduced -5.5k |
| Vident Advisory, LLC 0.09% of their portfolio | 388.9k $10.1m | Added +6.3k |
| De Lisle Partners LLP 1.18% of their portfolio | 379.8k $9.9m | New |
| Aristotle Capital Boston, LLC 0.56% of their portfolio | 345.0k $9.0m | Reduced -13.9k |
| Legal & General Group Plc 0.00% of their portfolio | 334.9k $8.7m | Reduced -33.7k |
| HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC 0.03% of their portfolio | 333.8k $8.7m | Added +65.4k |
| Mawer Investment Management Ltd. 0.06% of their portfolio | 333.8k $8.7m | New |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio | 330.0k $8.6m | New |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 329.7k $8.6m | Reduced -8.9k |
| Rovida Investment Management Ltd 1.03% of their portfolio | 315.0k $8.2m | New |
| Swiss National Bank 0.00% of their portfolio | 313.4k $8.2m | Added +1.6k |
| Hyperion Capital Advisors LP 3.81% of their portfolio | 303.6k $7.9m | Reduced -188.3k |
| RHUMBLINE ADVISERS 0.01% of their portfolio | 300.3k $7.8m | Added +8.9k |
| EXCHANGE TRADED CONCEPTS, LLC 0.06% of their portfolio | 295.0k $7.7m | Reduced -15.5k |
| SEI INVESTMENTS CO 0.01% of their portfolio | 294.7k $7.7m | Added +77.6k |
| GRIZZLYROCK CAPITAL, LLC 5.97% of their portfolio | 289.1k $7.5m | Added +4.0k |
| California Public Employees Retirement System 0.00% of their portfolio | 277.1k $7.2m | Reduced -1.6k |
| SG Americas Securities, LLC 0.01% of their portfolio | 274.6k $7.2m | Reduced -70.7k |
| FIFTH THIRD BANCORP 0.01% of their portfolio | 273.3k $7.1m | Added +270.7k |
| FIRST NATIONAL BANK OF OMAHA 0.19% of their portfolio | 248.0k $6.3m | Added +70.3k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 248.0k $6.5m | Reduced -5.1k |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 245.8k $6.4m | Added +77.8k |
| Soviero Asset Management, LP 3.51% of their portfolio | 240.0k $6.3m | Added +62.0k |
| AWH Capital, L.P. 5.57% of their portfolio | 235.2k $6.1m | Unchanged |
| ROYAL BANK OF CANADA 0.00% of their portfolio | 231.7k $6.0m | Reduced -34.8k |
| FIRST TRUST ADVISORS LP 0.00% of their portfolio | 228.1k $5.9m | Reduced -149.7k |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC 0.21% of their portfolio | 217.8k $5.7m | Reduced -2.2k |
| Hudson Value Partners, LLC 1.59% of their portfolio | 203.9k $5.3m | Added +15.9k |
| JANE STREET GROUP, LLC 0.01% of their portfolio | 192.0k $5.0m | Added +181.2k |
| Telos Capital Management, Inc. 0.47% of their portfolio | 189.9k $5.0m | Added +2.4k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio | 184.6k $4.8m | Added +34.6k |
| Hel Ved Capital Management Ltd 0.81% of their portfolio | 178.5k $4.7m | New |
| North Growth Management Ltd. 0.69% of their portfolio | 172.0k $4.5m | Added +74.0k |
| OpenArc Corporate Advisory, LLC 0.06% of their portfolio | 170.4k $4.4m | Reduced -30.0k |
| OPPENHEIMER & CO INC 0.05% of their portfolio | 168.9k $4.4m | New |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio | 165.3k $4.3m | Reduced -728 |
| WEDGE CAPITAL MANAGEMENT L L P/NC 0.08% of their portfolio | 164.7k $4.3m | New |
| Quantinno Capital Management LP 0.01% of their portfolio | 145.6k $3.8m | Added +67.6k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 145.3k $3.8m | Added +15.8k |
| CenterBook Partners LP 0.20% of their portfolio | 143.7k $3.7m | Reduced -78.5k |
| PRUDENTIAL FINANCIAL INC 0.00% of their portfolio | 140.4k $3.7m | Reduced -2.0k |
| VANGUARD ASSET MANAGEMENT, Ltd 0.00% of their portfolio | 127.8k $3.3m | First filing |
| BESSEMER GROUP INC 0.01% of their portfolio | 126.0k $3.3m | Added +124.2k |
| Holocene Advisors, LP 0.01% of their portfolio | 123.2k $3.2m | Added +43.9k |
| South Dakota Investment Council 0.06% of their portfolio | 123.0k $3.2m | Unchanged |