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 ($3.3m this quarter). Holder counts are more reliable. Shares outstanding: 244.5m as of 2026-08-07, 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 ≈ $19.84. Options: 15 managers hold calls ($49.7m notional), 12 hold puts ($22.2m).
Trends to Q2 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 |
| Q2 2026 | 460 |
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 |
| Q2 2026 | 200 | 232 |
Calls vs puts
Options held, notional value, last 4 quarters. P/C = puts ÷ calls
Numbers
| Quarter | Calls | Puts | P/C |
|---|---|---|---|
| Q3 2025 | $22.9m | $15.4m | 0.67 |
| Q4 2025 | $85.8m | $30.3m | 0.35 |
| Q1 2026 | $134.1m | $43.0m | 0.32 |
| Q2 2026 | $49.7m | $22.2m | 0.45 |
Biggest buyers
| Invesco Ltd. | Added | +3.5m |
| Troluce Capital Advisors LLC | Added | +2.6m |
| DIMENSIONAL FUND ADVISORS LP | Added | +1.8m |
| GOLDMAN SACHS GROUP INC | Added | +1.6m |
| MILLENNIUM MANAGEMENT LLC | Added | +1.5m |
| VAN ECK ASSOCIATES CORP | Added | +1.4m |
| Qube Research & Technologies Ltd | Added | +957.0k |
| VOYA INVESTMENT MANAGEMENT LLC | Added | +774.7k |
| THOMPSON SIEGEL & WALMSLEY LLC | Added | +756.1k |
| Verition Fund Management LLC | Added | +721.4k |
Biggest sellers
| Focus Partners Wealth | Reduced | -2.5m |
| Arvin Capital Management LP | Reduced | -1.7m |
| TORONTO DOMINION BANK | Sold out | -1.6m |
| BRIGHTLINE CAPITAL MANAGEMENT, LLC | Sold out | -1.4m |
| Ruane, Cunniff & Goldfarb L.P. | Reduced | -1.1m |
| Point72 Asset Management, L.P. | Reduced | -980.6k |
| COOPER CREEK PARTNERS MANAGEMENT LLC | Sold out | -929.3k |
| FRONTIER CAPITAL MANAGEMENT CO LLC | Reduced | -786.2k |
| Penn Capital Management Company, LLC | Sold out | -694.4k |
| FIL Ltd | Reduced | -650.8k |
Biggest calls
| Caption Management, LLC | Reduced | $10.3m500.0k shares |
| Arvin Capital Management LP | Reduced | $9.3m450.0k shares |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Reduced | $8.4m408.6k shares |
| SEGRA CAPITAL MANAGEMENT, LLC | Unchanged | $4.1m200.0k shares |
| Soviero Asset Management, LP | Added | $3.7m180.0k shares |
| JANE STREET GROUP, LLC | Reduced | $2.8m137.7k shares |
| GROUP ONE TRADING LLC | Reduced | $2.6m125.1k shares |
| IMC-Chicago, LLC | Added | $2.3m112.0k shares |
| CITADEL ADVISORS LLC | Reduced | $2.3m111.2k shares |
| NOMURA HOLDINGS INC | Unchanged | $971.5k47.0k shares |
Biggest puts
| SUSQUEHANNA INTERNATIONAL GROUP, LLP | Added | $10.7m516.5k shares |
| CITADEL ADVISORS LLC | Added | $4.0m192.4k shares |
| Caption Management, LLC | Reduced | $1.0m50.0k shares |
| NOMURA HOLDINGS INC | Unchanged | $971.5k47.0k shares |
| Lido Advisors, LLC | Unchanged | $857.8k41.5k shares |
| JANE STREET GROUP, LLC | Reduced | $797.9k38.6k shares |
| IMC-Chicago, LLC | Added | $775.1k37.5k shares |
| SIMPLEX TRADING, LLC | Added | $750.3k36.3k shares |
| GROUP ONE TRADING LLC | Reduced | $711.0k34.4k shares |
| Walleye Capital LLC | Added | $675.9k32.7k 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 since 1 Apr 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 |
|---|---|---|---|---|---|
| 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 | — | — |
| Q2 2026 | 0 | — | 0 | — | — |
| Q3 2026 | 0 | — | 0 | — | — |
None reported since 1 Apr 2026.
Holders, Q2 2026
| Manager | Shares | Change |
|---|---|---|
| AMERICAN SECURITIES LLC 24.79% of their portfolio | 45.0m $930.7m | Unchanged |
| Invesco Ltd. 0.04% of their portfolio | 25.0m $515.8m | Added +3.5m |
| BlackRock, Inc. 0.01% of their portfolio | 17.9m $370.1m | Added +65.7k |
| PRIMECAP MANAGEMENT CO/CA/ 0.15% of their portfolio | 12.3m $253.9m | Added +200.2k |
| Legacy Advisors, LLC 0.85% of their portfolio | 9.1m $9.1m | Added +1.4k |
| VANGUARD PORTFOLIO MANAGEMENT LLC 0.01% of their portfolio | 7.9m $164.3m | Added +95.4k |
| VANGUARD CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 6.7m $138.7m | Added +61.1k |
| FMR LLC 0.01% of their portfolio | 5.7m $117.4m | Added +100.8k |
| DIMENSIONAL FUND ADVISORS LP 0.02% of their portfolio | 5.5m $114.5m | Added +1.8m |
| STATE STREET CORP 0.00% of their portfolio | 5.2m $106.5m | Added +72.7k |
| FRONTIER CAPITAL MANAGEMENT CO LLC 0.80% of their portfolio | 4.1m $85.7m | Reduced -786.2k |
| Troluce Capital Advisors LLC 27.60% of their portfolio | 3.6m $73.7m | Added +2.6m |
| GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio | 2.7m $56.2m | Reduced -97.9k |
| GOLDMAN SACHS GROUP INC 0.01% of their portfolio | 2.7m $56.1m | Added +1.6m |
| MORGAN STANLEY 0.00% of their portfolio | 2.7m $55.0m | Added +427.4k |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.06% of their portfolio | 2.3m $47.9m | Reduced -466.6k |
| THOMPSON SIEGEL & WALMSLEY LLC 0.85% of their portfolio | 2.3m $47.2m | Added +756.1k |
| MILLENNIUM MANAGEMENT LLC 0.03% of their portfolio | 2.1m $44.0m | Added +1.5m |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.01% of their portfolio | 2.1m $43.8m | Added +52.2k |
| Thrivent Financial for Lutherans 0.07% of their portfolio | 2.1m $43.5m | Added +5.3k |
| BANK OF AMERICA CORP /DE/ 0.00% of their portfolio | 2.0m $42.2m | Reduced -362.1k |
| SEGRA CAPITAL MANAGEMENT, LLC 9.68% of their portfolio | 2.0m $42.1m | Added +425.2k |
| Verition Fund Management LLC 0.29% of their portfolio | 2.0m $41.7m | Added +721.4k |
| VAN ECK ASSOCIATES CORP 0.03% of their portfolio | 2.0m $41.1m | Added +1.4m |
| VOYA INVESTMENT MANAGEMENT LLC 0.04% of their portfolio | 2.0m $40.8m | Added +774.7k |
| UBS Group AG 0.01% of their portfolio | 1.5m $31.9m | Reduced -165.6k |
| NORGES BANK 0.00% of their portfolio | 1.5m $31.3m | Not comparable |
| Permian Investment Partners, LP 3.36% of their portfolio | 1.4m $29.6m | Reduced -134.0k |
| 683 Capital Management, LLC 2.09% of their portfolio | 1.1m $22.7m | Added +325.0k |
| LOOMIS SAYLES & CO L P 0.03% of their portfolio | 1.0m $21.5m | Reduced -38.8k |
| Qube Research & Technologies Ltd 0.02% of their portfolio | 1.0m $21.4m | Added +957.0k |
| NORTHERN TRUST CORP 0.00% of their portfolio | 1.0m $21.3m | Added +45.8k |
| VANGUARD FIDUCIARY TRUST CO 0.00% of their portfolio | 968.5k $20.0m | Added +21.0k |
| CACTI ASSET MANAGEMENT LLC 0.91% of their portfolio | 881.7k $18.2m | Unchanged |
| Bank of New York Mellon Corp 0.00% of their portfolio | 878.1k $18.2m | Reduced -30.5k |
| Russell Investments Group, Ltd. 0.02% of their portfolio | 840.6k $17.4m | Added +126.8k |
| AVENIR CORP 2.04% of their portfolio | 811.7k $16.8m | Reduced -29.4k |
| WELLS FARGO & COMPANY/MN 0.00% of their portfolio | 750.2k $15.5m | Added +113.5k |
| PRINCIPAL FINANCIAL GROUP INC 0.01% of their portfolio | 742.4k $15.3m | Reduced -2.3k |
| Ancora Advisors LLC 0.29% of their portfolio | 715.7k $14.8m | Added +12.5k |
| ROYCE & ASSOCIATES LP 0.12% of their portfolio | 697.4k $14.4m | Added +147.6k |
| HRT FINANCIAL LP 0.03% of their portfolio | 671.8k $13.9m | New |
| CITADEL ADVISORS LLC 0.01% of their portfolio | 670.7k $13.9m | Added +590.0k |
| Point72 Asset Management, L.P. 0.02% of their portfolio | 650.0k $13.4m | Reduced -980.6k |
| AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio | 601.9k $12.4m | Added +94.1k |
| FIRST TRUST ADVISORS LP 0.01% of their portfolio | 547.9k $11.3m | Added +319.8k |
| Ruane, Cunniff & Goldfarb L.P. 0.17% of their portfolio | 537.2k $11.1m | Reduced -1.1m |
| Public Sector Pension Investment Board 0.03% of their portfolio | 528.8k $10.9m | Reduced -21.0k |
| Loews Corp 0.08% of their portfolio | 500.0k $10.3m | New |
| FIRST NATIONAL BANK OF OMAHA 0.27% of their portfolio | 476.0k $9.7m | Added +228.0k |
| SHAPIRO CAPITAL MANAGEMENT LLC 0.60% of their portfolio | 476.0k $9.8m | New |
| AWH Capital, L.P. 3.37% of their portfolio | 470.5k $9.7m | Added +235.2k |
| Nuveen, LLC 0.00% of their portfolio | 421.5k $8.7m | Reduced -450.3k |
| Arvin Capital Management LP 1.61% of their portfolio | 416.7k $8.6m | Reduced -1.7m |
| HOTCHKIS & WILEY CAPITAL MANAGEMENT LLC 0.02% of their portfolio | 402.1k $8.3m | Added +68.3k |
| SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC 0.15% of their portfolio | 394.4k $8.2m | Added +176.6k |
| BOOTHBAY FUND MANAGEMENT, LLC 0.15% of their portfolio | 388.0k $8.0m | Added +301.8k |
| De Lisle Partners LLP 0.85% of their portfolio | 374.8k $7.7m | Reduced -5.0k |
| Vident Advisory, LLC 0.06% of their portfolio | 372.9k $7.7m | Reduced -15.9k |
| Mawer Investment Management Ltd. 0.05% of their portfolio | 369.6k $7.6m | Added +35.8k |
| MOORE CAPITAL MANAGEMENT, LP 0.17% of their portfolio | 365.1k $7.5m | Reduced -508.5k |
| Legal & General Group Plc 0.00% of their portfolio | 349.0k $7.2m | Added +14.2k |
| JANE STREET GROUP, LLC 0.00% of their portfolio | 343.7k $7.1m | Added +151.7k |
| SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.01% of their portfolio | 332.5k $6.9m | Added +2.4k |
| CenterBook Partners LP 0.33% of their portfolio | 328.8k $6.8m | Added +185.1k |
| AMERIPRISE FINANCIAL INC 0.00% of their portfolio | 319.5k $6.6m | Reduced -10.3k |
| GRIZZLYROCK CAPITAL, LLC 4.60% of their portfolio | 318.4k $6.6m | Added +29.2k |
| Swiss National Bank 0.00% of their portfolio | 318.1k $6.6m | Added +4.7k |
| Rovida Investment Management Ltd 0.44% of their portfolio | 315.0k $6.5m | Unchanged |
| Aristotle Capital Boston, LLC 0.43% of their portfolio | 307.8k $6.4m | Reduced -37.1k |
| EXCHANGE TRADED CONCEPTS, LLC 0.03% of their portfolio | 305.3k $6.3m | Added +10.3k |
| TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio | 284.3k $5.9m | Reduced -615.9k |
| RHUMBLINE ADVISERS 0.00% of their portfolio | 284.1k $5.9m | Reduced -16.2k |
| FIFTH THIRD BANCORP 0.01% of their portfolio | 281.8k $5.8m | Added +8.5k |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio | 273.6k $1.1m | Added +232.7k |
| California Public Employees Retirement System 0.00% of their portfolio | 266.4k $5.5m | Reduced -10.7k |
| SG Americas Securities, LLC 0.00% of their portfolio | 263.0k $5.4m | Reduced -11.6k |
| Hudson Value Partners, LLC 1.30% of their portfolio | 250.2k $5.2m | Added +46.3k |
| UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio | 249.7k $5.2m | Added +1.8k |
| CSM Advisors, LLC 0.11% of their portfolio | 243.8k $5.0m | Added +162.6k |
| ExodusPoint Capital Management, LP 0.04% of their portfolio | 226.3k $4.7m | New |
| RAYMOND JAMES FINANCIAL INC 0.00% of their portfolio | 224.4k $4.6m | Reduced -21.4k |
| Hel Ved Capital Management Ltd 0.62% of their portfolio | 214.0k $4.4m | Added +35.5k |
| D. E. Shaw & Co., Inc. 0.00% of their portfolio | 191.5k $4.0m | Added +125.3k |
| SEI INVESTMENTS CO 0.00% of their portfolio | 190.1k $3.9m | Reduced -104.6k |
| WEDGE CAPITAL MANAGEMENT L L P/NC 0.06% of their portfolio | 187.8k $3.9m | Added +23.2k |
| Verbena Value LP 0.64% of their portfolio | 186.2k $3.8m | New |
| Telos Capital Management, Inc. 0.34% of their portfolio | 185.6k $3.8m | Reduced -4.3k |
| CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio | 183.2k $3.8m | Reduced -1.3k |
| North Growth Management Ltd. 0.46% of their portfolio | 173.0k $3.6m | Added +1.0k |
| OpenArc Corporate Advisory, LLC 0.04% of their portfolio | 170.3k $3.5m | Reduced -61 |
| Brevan Howard Capital Management LP 0.05% of their portfolio | 167.4k $3.5m | Added +90.2k |
| NEW YORK STATE TEACHERS RETIREMENT SYSTEM 0.01% of their portfolio | 162.0k $3.3m | Reduced -3.3k |
| Atom Investors LP 0.30% of their portfolio | 160.9k $3.3m | Added +138.1k |
| Gotham Asset Management, LLC 0.01% of their portfolio | 156.1k $3.2m | Reduced -364.9k |
| PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio | 152.1k $3.1m | Added +6.8k |
| BARCLAYS PLC 0.00% of their portfolio | 151.8k $3.1m | Added +105.0k |
| Soviero Asset Management, LP 1.50% of their portfolio | 150.0k $3.1m | Reduced -90.0k |
| OPPENHEIMER & CO INC 0.03% of their portfolio | 143.0k $3.0m | Reduced -25.9k |
| Bryn Mawr Trust Advisors, LLC 0.13% of their portfolio | 141.4k $2.9m | Added +24.6k |