MAMMOTH ENERGY SERVICES, INC. TUSK
CIK 0001679268 · CUSIP 56155L108
Quarter-end disclosures, not live holdings.
Top 20 institutions
Weight means this stock's share of the manager's own portfolio.
| # | Manager | Value | Manager weight | Change vs prior | Source | |
|---|---|---|---|---|---|---|
| 01 | WEXFORD CAPITAL LP CIK 1048462 · View history | $39.23M 12,071,823 shares | 5.38% | -10.00M(-45.3%)Reduced | SEC filing ↗ Aug 14, 2026 | ▾ |
| 02 | ADAGE CAPITAL PARTNERS GP, L.L.C. CIK 1165408 · View history | $14.87M 4,575,000 shares | 0.02% | 0(0.0%)Unchanged | SEC filing ↗ Aug 14, 2026 | ▾ |
| 03 | VANGUARD CAPITAL MANAGEMENT LLC CIK 2100119 · View history | $3.44M 1,059,603 shares | 0.00% | +240.48K(+29.4%)Added | SEC filing ↗ Aug 13, 2026 | ▾ |
| 04 | Peapod Lane Capital LLC CIK 2050979 · View history | $2.63M 807,804 shares | 1.77% | +208.00K(+34.7%)Added | SEC filing ↗ Jul 27, 2026 | ▾ |
| 05 | DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history | $2.25M 691,667 shares | 0.00% | +5.47K(+0.8%)Added | SEC filing ↗ Aug 11, 2026 | ▾ |
| 06 | JANE STREET GROUP, LLC CIK 1595888 · View history | $1.65M 506,662 shares | 0.00% | +483.81K(+2117.0%)Added | SEC filing ↗ Aug 14, 2026 | ▾ |
| 07 | CITADEL ADVISORS LLC CIK 1423053 · Amended · View history | $1.47M 452,163 shares | 0.00% | +120.80K(+36.5%)Added | SEC filing ↗ Sep 2, 2026 | ▾ |
| 08 | BlackRock, Inc. CIK 2012383 · View history | $1.33M 407,976 shares | 0.00% | -1.05M(-72.0%)Reduced | SEC filing ↗ Aug 7, 2026 | ▾ |
| 09 | MARSHALL WACE, LLP CIK 1318757 · View history | $1.29M 395,583 shares | 0.00% | +395.58KNew | SEC filing ↗ Aug 13, 2026 | ▾ |
| 10 | Johns Hopkins University CIK 1764756 · View history | $1.26M 387,359 shares | 0.08% | +387.36KNew | SEC filing ↗ Aug 14, 2026 | ▾ |
| 11 | BRIDGEWAY CAPITAL MANAGEMENT, LLC CIK 1107261 · View history | $1.08M 332,313 shares | 0.02% | 0(0.0%)Unchanged | SEC filing ↗ Aug 14, 2026 | ▾ |
| 12 | Russell Investments Group, Ltd. CIK 1692234 · View history | $1.07M 329,821 shares | 0.00% | +261.79K(+384.8%)Added | SEC filing ↗ Aug 6, 2026 | ▾ |
| 13 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $995.73K 306,028 shares | 0.00% | -304.90K(-49.9%)Reduced | SEC filing ↗ Aug 12, 2026 | ▾ |
| 14 | RENAISSANCE TECHNOLOGIES LLC CIK 1037389 · View history | $949.91K 292,280 shares | 0.00% | +60.31K(+26.0%)Added | SEC filing ↗ Aug 13, 2026 | ▾ |
| 15 | ARROWSTREET CAPITAL, LIMITED PARTNERSHIP CIK 1164508 · View history | $942.81K 290,096 shares | 0.00% | +290.10KNew | SEC filing ↗ Aug 13, 2026 | ▾ |
| 16 | Empowered Funds, LLC CIK 1592828 · View history | $784.27K 241,313 shares | 0.00% | 0(0.0%)Unchanged | SEC filing ↗ Aug 17, 2026 | ▾ |
| 17 | AQR CAPITAL MANAGEMENT LLC CIK 1167557 · View history | $577.93K 177,824 shares | 0.00% | +111.09K(+166.5%)Added | SEC filing ↗ Aug 14, 2026 | ▾ |
| 18 | VANGUARD FIDUCIARY TRUST CO CIK 933478 · View history | $525.82K 161,791 shares | 0.00% | -8.34K(-4.9%)Reduced | SEC filing ↗ Aug 13, 2026 | ▾ |
| 19 | Round Rock Advisors LLC CIK 1846991 · View history | $496.73K 152,841 shares | 0.06% | +152.84KNew | SEC filing ↗ Aug 12, 2026 | ▾ |
| 20 | MORGAN STANLEY CIK 895421 · View history | $434.07K 133,560 shares | 0.00% | -19.16K(-12.5%)Reduced | SEC filing ↗ Aug 13, 2026 | ▾ |
Showing 20 / 93 institutions. The complete set is available through the API.
Coverage & totals by quarter
Reporting institutions by quarter
Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.
Explore all 93 reporting institutions.
This page includes 20 of 93 reporting institutions. Sign in to look up the full history beyond 3 years, use advanced screening & filtering, download CSV, and get the complete set through the Akkru API.
- Download CSV
- Earlier quarters
- Advanced screening & filtering
- API & AI access
+ New accounts get free API credits to explore data beyond ownership filings.
For AI agents & developers
The initial HTML of this page carries its exact data as script#research-data (JSON): values, units, scope, preview limits and SEC sources. Read it directly, no script or API key needed; script#research-access says what needs an account. This page lists 20 of 93 reporting institutions; totals use the complete disclosed data.
Without an account: the last 3 years, with the row caps stated on the page. A free account opens all history on file on these pages and the CSV of what a page shows. Rows beyond the caps and bulk retrieval go through the authenticated API / MCP.
MCP https://api.akkrudata.ai/mcp
get_institutional_security_holders
{"cusip":"56155L108","quarter":"2026Q2","type":"positions","page_size":100}Connect to MCP with OAuth and follow the returned pagination. Credits and usage limits depend on the account.
- MCP endpoint
- https://api.akkrudata.ai/mcp
- API / MCP documentation
- /documents
- llms.txt
- /llms.txt
Sources, coverage & how to read this data
Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.