Amentum Holdings
AMTM
18.51
-0.26
-1.39%
Amentum Holdings
US · AMTM
#2202 by market cap
Listed 2024
18.51
-0.26
-1.39%
Live - 5344 symbols - heartbeat 372s ago
· 2026-10-08 08:30
Pre-market
18.48
-0.19%
After-hours
18.80
+1.57%
Overnight
18.65
+0.76%
- Market cap
- 4.53B
- P/E (TTM)i
- 22.27
- P/Bi
- 0.96
- EPSi
- 0.27
- Div yieldi
- 0.00%
- 52W posi
- 4%
Reader sentiment
Are you bullish or bearish on AMTM?
Anonymous reader poll. Unscientific, not investment advice.
✦ Quant Ownership Signal how this is computed
Accumulating
- The number of reporting institutions decreased by 1 in the most recent period (2026/Q3).
- Total institutional ownership rose 0.2 percentage points.
Institutional ownership
- Held by institutions
- 106.27% +0.22pp
- Institutions
- 544 -1
- As of
- 2026/Q3 vs. prior period
Ownership vs. money flow
DivergingInstitutions added shares last reporting period, and the stock has seen net outflows in main-fund flow over the last 20 trading sessions - the two are pointing in different directions.
Institutional ownership changes are reported quarterly with a lag; fund-flow data is daily. Treat this as a directional cross-check, not a precise timing signal.
Holder types
Mutual Fund57.19%
VC/PE Fund37.77%
Hedge Fund5.26%
Public Company2.88%
Private Company1.04%
Government Pension Fund0.89%
Individual/Insider0.74%
Sovereign Wealth Fund0.63%
Family Office/Trust0.52%
Top holders as of 2026-06-30
American Securities LLC
18.42% · 45.03M sh
Lindsay Goldberg LLC
18.42% · 45.03M sh
Invesco Ltd.
8.75% · 21.40M sh
BlackRock
7.32% · 17.91M sh
PRIMECAP Management Company
5.02% · 12.29M sh
Vanguard Portfolio Management, LLC
3.25% · 7.95M sh
Vanguard Capital Management, LLC
3.14% · 7.68M sh
FMR
2.30% · 5.62M sh
Dimensional Fund Advisors
2.26% · 5.54M sh
State Street Global Advisors
2.11% · 5.15M sh
Bar length is relative to the largest holder shown here, not to 100% of the company.
Insiders
50 filings tracked · 34 buys · 16 sells
| Name | Role | Stake |
|---|---|---|
| American Securities LLC | -- | 18.42% |
| Lindsay Goldberg LLC | -- | 18.42% |
| Steven Demetriou | Executive Chairperson | 0.30% |
| John Vollmer | Chairperson | 0.17% |
| John Heller | Chief Executive Officer | 0.09% |
| Jill Bruning | President of Engineering, Science & Technology | 0.07% |
| Stephen Arnette | Chief Operating Officer | 0.02% |
| Ralph Eberhart | Independent Director | 0.02% |
| Michele St. Mary | Chief Legal Officer & General Counsel | 0.01% |
| Darren Burton | Chief Human Resources Officer | 0.01% |
Insider transactions most recent Form 4 filings
| Date | Name | Role | Type | Shares | Price |
|---|---|---|---|---|---|
| 2026-08-13 | Christopher M. Thompson | Director | Other Disposition | -4,250 | -- |
| 2026-05-05 | John Heller | Chief Executive Officer | Derivative Exercise and Sale | -8,184 | $24.89 |
| 2026-05-05 | John Heller | Chief Executive Officer | Derivative Exercise and Retained | +9,961 | -- |
| 2026-05-05 | Jill Bruning | President of Engineering, Science & Technology | Derivative Exercise and Sale | -2,731 | $24.89 |
| 2026-05-05 | Jill Bruning | President of Engineering, Science & Technology | Derivative Exercise and Retained | +6,341 | -- |
| 2026-05-05 | Travis Johnson | Chief Financial Officer | Derivative Exercise and Sale | -4,097 | $24.89 |
| 2026-05-05 | Travis Johnson | Chief Financial Officer | Derivative Exercise and Retained | +9,512 | -- |
| 2026-05-05 | Stephen Arnette | Chief Operating Officer | Derivative Exercise and Sale | -3,314 | $24.89 |
| 2026-05-05 | Stephen Arnette | Chief Operating Officer | Derivative Exercise and Retained | +10,295 | -- |
| 2026-05-05 | Sean Mullen | Officer | Derivative Exercise and Sale | -2,762 | $24.89 |
| 2026-05-05 | Sean Mullen | Officer | Derivative Exercise and Retained | +6,310 | -- |
| 2026-03-03 | Jill Bruning | President of Engineering, Science & Technology | Other Disposition | -30,000 | -- |
| 2026-03-01 | Stephen Arnette | Chief Operating Officer | Derivative Exercise and Sale | -750 | $30.70 |
| 2026-03-01 | Stephen Arnette | Chief Operating Officer | Derivative Exercise and Retained | +2,058 | -- |
| 2026-02-16 | Michele St. Mary | Chief Legal Officer & General Counsel | Derivative Exercise and Sale | -2,308 | $30.05 |
| 2026-02-16 | Michele St. Mary | Chief Legal Officer & General Counsel | Derivative Exercise and Retained | +4,772 | -- |
| 2026-02-05 | Christopher M. Thompson | Director | Other Acquisition | +5,062 | -- |
| 2026-02-05 | Ralph Eberhart | Independent Director | Other Acquisition | +5,062 | -- |
| 2026-02-05 | Ralph Eberhart | Independent Director | Derivative Exercise and Retained | +11,564 | -- |
| 2026-02-05 | Sandra Rowland | Independent Director | Other Acquisition | +5,062 | -- |
Form 4 filings, most recent per company. "Other Derivative Acquisition" rows are mostly RSU/option vesting, not open-market buying - the Type column says which.
Quote time 2026-10-08 08:30:15 · For reference only, not investment advice and not tailored to your situation.