Mammoth Energy Services
TUSK · NASDAQ
$2.69−$0.01 (−0.37%)TodayMarket closed ·
Prev close $2.70
Who owns TUSK
Largest institutional holders, from their latest 13F filings
The 10 largest institutions hold 57.0% of TUSK’s shares.
- Wexford Capital LP25.1%
- Davidson (Charles E)13.4%
- Adage Capital Management, L.P.9.5%
- Vanguard Capital Management, LLC2.2%
- Next 6 largest institutions6.8%
- All other shareholders43.0%
| Holder | Shares | % of shares |
|---|---|---|
| Wexford Capital LP | 12.07M | 25.06% |
| Davidson (Charles E) | 6.47M | 13.43% |
| Adage Capital Management, L.P. | 4.58M | 9.50% |
| Vanguard Capital Management, LLC | 1.06M | 2.20% |
| Peapod Lane Capital LLC | 807.80K | 1.68% |
| Dimensional Fund Advisors, L.P. | 691.67K | 1.44% |
| Jane Street Capital, L.L.C. | 506.66K | 1.05% |
| Citadel Advisors LLC | 452.16K | 0.94% |
| Layton (Mark E) | 418.99K | 0.87% |
| Marshall Wace LLP | 395.58K | 0.82% |
Largest mutual fund holders
| Holder | Shares | % of shares |
|---|---|---|
| Vanguard Total Stock Market Index Fund | 767.90K | 1.59% |
| Vanguard Extended Market Index Fund | 280.49K | 0.58% |
| EA Bridgeway Omni Small-Cap Value ETF | 257.00K | 0.53% |
| DFA US Small Cap Portfolio | 156.44K | 0.32% |
| DFA Dimensional US Small Cap ETF | 154.80K | 0.32% |
Insider trades
Form 4 filings by officers, directors and large holders
Over the last 6 months, insiders bought $10.52M (6 trades) of TUSK on the open market, with no sales.
| Insider | Type | Shares | Value |
|---|---|---|---|
| Plaumann Mark Lawrence | Buy | 5.00K | $15.00K |
| Lancaster Phillip | Other | 68.15K | — |
| Jacobi Paul M. | Other | 3.21K | — |
| Amron Arthur H | Other | 10.33K | — |
| Amron Arthur H | Other | 19.12K | — |
| DAVIDSON CHARLES E | Buy | 4.02M | $10.47M |
| DAVIDSON CHARLES E | Other | 6.35M | — |
| DAVIDSON CHARLES E | Other | 1.07M | — |
| DAVIDSON CHARLES E | Other | 4.07M | — |
| DAVIDSON CHARLES E | Other | 2.40M | — |
Short interest
Settled Sep 30, 2026
- Shares short
- 110.52K
- Days to cover
- 1.18
- % of shares outstanding
- 0.23%
- Average daily volume
- 93.68K
- Change since last report
- +24.4%
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