Who owns MAMMOTH ENERGY SERVICES, INC.?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of TUSK from SEC Form 13F filings across 94 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 94 institutions disclosed 26.0M shares of MAMMOTH ENERGY SERVICES, INC. worth $83.4M — about 54% of shares outstanding; the largest disclosed holder is WEXFORD CAPITAL LP. Source: SEC Form 13F filings, parsed by EvidInvest.
94
13F holders
$83.4M
value, 2026 filers
54%
of shares outstanding (26.0M sh)
30
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of TUSK's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | WEXFORD CAPITAL LP | 12.1M | $39.2M | 5.0% | 25.1% | -45.3% |
| 2 | ADAGE CAPITAL PARTNERS GP, L.L.C. | 4.6M | $14.9M | 0.0% | 9.5% | 0.0% |
| 3 | VANGUARD CAPITAL MANAGEMENT LLC | 1.1M | $3.4M | 0.0% | 2.2% | +29.4% |
| 4 | Peapod Lane Capital LLC | 807,804 | $2.6M | 1.8% | 1.7% | +34.7% |
| 5 | DIMENSIONAL FUND ADVISORS LP | 691,667 | $2.2M | 0.0% | 1.4% | +0.8% |
| 6 | JANE STREET GROUP, LLC | 506,662 | $1.6M | 0.0% | 1.1% | +2117.0% |
| 7 | CITADEL ADVISORS LLC | 452,163 | $1.5M | 0.0% | 0.9% | +36.5% |
| 8 | BlackRock, Inc. | 407,976 | $1.3M | 0.0% | 0.8% | -72.0% |
| 9 | MARSHALL WACE, LLPNEW | 395,583 | $1.3M | 0.0% | 0.8% | new |
| 10 | Johns Hopkins UniversityNEW | 387,359 | $1.3M | 0.1% | 0.8% | new |
| 11 | BRIDGEWAY CAPITAL MANAGEMENT, LLC | 332,313 | $1.1M | 0.0% | 0.7% | 0.0% |
| 12 | Russell Investments Group, Ltd. | 329,821 | $1.1M | 0.0% | 0.7% | +384.8% |
| 13 | GEODE CAPITAL MANAGEMENT, LLC | 306,028 | $995,730 | 0.0% | 0.6% | -49.9% |
| 14 | RENAISSANCE TECHNOLOGIES LLC | 292,280 | $949,910 | 0.0% | 0.6% | +26.0% |
| 15 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIPNEW | 290,096 | $942,812 | 0.0% | 0.6% | new |
| 16 | Empowered Funds, LLC | 241,313 | $784,267 | 0.0% | 0.5% | 0.0% |
| 17 | AQR CAPITAL MANAGEMENT LLC | 177,824 | $577,928 | 0.0% | 0.4% | +166.5% |
| 18 | VANGUARD FIDUCIARY TRUST CO | 161,791 | $525,821 | 0.0% | 0.3% | -4.9% |
| 19 | Round Rock Advisors LLCNEW | 152,841 | $496,733 | 0.1% | 0.3% | new |
| 20 | MORGAN STANLEY | 133,560 | $434,070 | 0.0% | 0.3% | -12.5% |
| 21 | Centiva Capital, LP | 130,870 | $425,328 | 0.0% | 0.3% | +17.8% |
| 22 | GSA CAPITAL PARTNERS LLP | 129,547 | $421 | 0.0% | 0.3% | +831.4% |
| 23 | MILLENNIUM MANAGEMENT LLCNEW | 124,186 | $403,604 | 0.0% | 0.3% | new |
| 24 | ACADIAN ASSET MANAGEMENT LLC | 122,050 | $396 | 0.0% | 0.3% | -40.2% |
| 25 | Marquette Asset Management, LLCNEW | 109,826 | $356,935 | 0.0% | 0.2% | new |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation · options positioning · supply chain. Research, not investment advice.