Mammoth Energy Services, Inc.
TUSK- Exchange
- Nasdaq
- Industry
- Oil & Gas Field Services, NEC
- SEC CIK
- 0001679268
In the last 90 days, Mammoth Energy Services, Inc. insiders filed 1 open-market purchase and 0 sales; 93 institutions reported holding it in 13F filings for Q2 2026, worth $84.7M in total; no superinvestor holds it.
Key figures
- Insider buysLast 90 days, $15.0K in total
- 1
- Insider sellsOpen market, last 90 days
- 0
- 13F holdersQ2 2026, +4 vs. previous quarter
- 93
- 13F valueReported value at the end of Q2 2026
- $84.7M
- Superinvestors holdingAt the end of Q2 2026
- 0
Price chart
Superinvestors holding TUSK, Q2 2026
No superinvestor reported holding TUSK at the end of Q2 2026.
Latest insider trades
Open-market purchases and sales by Mammoth Energy Services, Inc. insiders from Form 4, newest first.
| Filed (ET) | Trade date | Filing delay | Insider | Transaction | Shares | Avg price | Value | Holding change | Flags |
|---|---|---|---|---|---|---|---|---|---|
| Sep 17, 2026 (view filing)4:50 PM ET | Sep 16 | 1 day | Plaumann Mark LawrenceDirector | PPurchase | +5.00K | $3.00 | +$15.0K | New position5.00K after | |
| Jun 22, 2026 (view filing)4:26 PM ET | Jun 17 | 5 days | Davidson Charles E and 3 othersChief Business Officer | PPurchase | +4.02M | $2.60 | +$10.5M | +60.9%10.6M after | |
| Jun 15, 2026 (view filing) | Jun 11-12 | 4 days | Amron Arthur HDirector | PPurchase | +4.50K | $3.25 | +$14.6K | +7.2%67.1K after | 2 lots |
| May 28, 2026 (view filing) | May 26-28 | 2 days | Amron Arthur HDirector | PPurchase | +5.50K | $3.25 | +$17.9K | +9.6%62.6K after | 2 lots |
| Dec 15, 2025 (view filing) | Dec 11 | 4 days | Amron Arthur HDirector | PPurchase | +10.0K | $1.89 | +$18.9K | +21.2%57.1K after | |
| May 27, 2025 (view filing) | May 22 | 5 days | Smith Arthur LDirector | SSale | −20.0K | $2.51 | −$50.2K | −13.3%130.0K after | |
| May 21, 2025 (view filing) | May 19-20 | 2 days | Smith Arthur LDirector | SSale | −65.0K | $2.51 | −$162.8K | −30.2%150.0K after | 2 lots |
| Dec 16, 2024 (view filing) | Dec 12 | 4 days | Amron Arthur HDirector | PPurchase | +1.00K | $2.97 | +$2.97K | +2.2%47.1K after | |
| Nov 26, 2024 (view filing) | Nov 22-25 | 4 days | Booker Corey J.Director | SSale | −25.0K | $3.45 | −$86.3K | −16.6%125.5K after | 2 lots |
| Nov 22, 2024 (view filing) | Nov 20-21 | 2 days | Booker Corey J.Director | SSale | −11.7K | $3.23 | −$37.9K | −7.2%150.5K after | 2 lots |
Top 10 13F holders, Q2 2026
The largest institutional positions in Mammoth Energy Services, Inc. at the end of Q2 2026; share changes are against Q1 2026.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Wexford Capital LP | 12,071,823 | $39.2M | 5.38% | −9,996,389−45.3% | Reduced |
| Adage Capital Partners GP, L.L.C. | 4,575,000 | $14.9M | 0.02% | 00.0% | Unchanged |
| Vanguard Capital Management LLC | 1,059,603 | $3.44M | 0.00% | +240,483+29.4% | Added |
| Peapod Lane Capital LLC | 807,804 | $2.63M | 1.77% | +207,999+34.7% | Added |
| Dimensional Fund Advisors LP | 691,667 | $2.25M | 0.00% | +5,468+0.8% | Added |
| Jane Street Group, LLC | 506,662 | $1.65M | 0.00% | +483,808+2,117.0% | Added |
| Citadel Advisors LLC | 452,163 | $1.47M | 0.00% | +120,796+36.5% | Added |
| BlackRock, Inc. | 407,976 | $1.33M | 0.00% | −1,046,863−72.0% | Reduced |
| Marshall Wace, LLP | 395,583 | $1.29M | 0.00% | +395,583 | New |
| Johns Hopkins University | 387,359 | $1.26M | 0.08% | +387,359 | New |