Amentum Holdings
AMTM
483 hedge funds and large institutions have $5.64B invested in Amentum Holdings in 2025 Q4 according to their latest regulatory filings, with 88 funds opening new positions, 132 increasing their positions, 159 reducing their positions, and 57 closing their positions.
143% more call options, than puts
Call options by funds: $73.7M | Put options by funds: $30.3M
54% more first-time investments, than exits
New positions opened: 88 | Existing positions closed: 57
22% more capital invested
Capital invested by funds: $4.63B → $5.64B (+$1.01B)
11% more funds holding in top 10
Funds holding in top 10: 9 → 10 (+1)
5% more funds holding
Funds holding: 462 → 483 (+21)
4.14% more ownership
Funds ownership: 79.49% → 83.63% (+4.1%)
17% less repeat investments, than reductions
Existing positions increased: 132 | Existing positions reduced: 159
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
LA
Legacy Advisors
Plymouth Meeting,
Pennsylvania
|
+$251M |
| 2 |
Focus Partners Wealth
Boston,
Massachusetts
|
+$70.6M |
| 3 |
CCPM
Cooper Creek Partners Management
New York
|
+$39.7M |
| 4 |
AQR Capital Management
Greenwich,
Connecticut
|
+$32.9M |
| 5 |
ECM
ExodusPoint Capital Management
New York
|
+$27.6M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
Kovitz Investment Group Partners
Chicago,
Illinois
|
-$72M |
| 2 |
FGP
Freestone Grove Partners
San Francisco,
California
|
-$49.1M |
| 3 |
State Street
Boston,
Massachusetts
|
-$45.3M |
| 4 |
DCM
Discovery Capital Management
South Norwalk,
Connecticut
|
-$27.3M |
| 5 |
TSW
Thompson Siegel & Walmsley
Richmond,
Virginia
|
-$20.7M |
AMTM Hedge Fund Activity: Q4 2025 in Review
483 of the 8,266 institutional investors tracked by Wall St. Rank reported a position in Amentum Holdings (AMTM) for Q4 2025, worth a combined $5.64B — up 22% from $4.63B a quarter earlier.
Buyers outnumbered sellers: 88 funds opened new AMTM positions and 57 closed out — a net gain of 31 holders — while 132 added to existing stakes and 159 trimmed.
The largest buyer was Legacy Advisors, opening a new position worth an estimated $251M. The largest seller was Kovitz Investment Group Partners, exiting entirely with an estimated $72M sold.
- 483 institutional investors held Amentum Holdings (AMTM) as of Q4 2025, up from 462 in Q3 2025.
- Funds reported $5.64B of Amentum Holdings stock for Q4 2025, up 22% quarter-over-quarter.
- 88 funds opened new Amentum Holdings positions in Q4 2025 and 57 closed out, a net change of +31 holders.
- The largest Amentum Holdings buyer in Q4 2025 was Legacy Advisors, an estimated $251M added.
- The largest Amentum Holdings seller in Q4 2025 was Kovitz Investment Group Partners, an estimated $72M sold.
Based on aggregated 13F filings for Q4 2025.