POWER SOLUTIONS INTERNATIONAL, INC. PSIX
CIK 0001137091 · CUSIP 73933G202
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 | GAGNON SECURITIES LLC CIK 1125725 · View history | $13.28M 525,291 shares | 2.92% | -324.86K(-38.2%)Reduced | SEC filing ↗ May 9, 2025 | ▾ |
| 02 | Gagnon Advisors, LLC CIK 1599466 · View history | $8.18M 323,484 shares | 5.77% | -146.68K(-31.2%)Reduced | SEC filing ↗ May 12, 2025 | ▾ |
| 03 | Portolan Capital Management, LLC CIK 1350290 · View history | $7.49M 296,442 shares | 0.57% | -44.84K(-13.1%)Reduced | SEC filing ↗ May 15, 2025 | ▾ |
| 04 | VANGUARD GROUP INC CIK 102909 · View history | $6.94M 274,693 shares | 0.00% | +274.69KNew | SEC filing ↗ May 9, 2025 | ▾ |
| 05 | MARSHALL WACE, LLP CIK 1318757 · View history | $6.65M 263,124 shares | 0.01% | +191.54K(+267.6%)Added | SEC filing ↗ May 15, 2025 | ▾ |
| 06 | S SQUARED TECHNOLOGY, LLC CIK 1322924 · View history | $4.12M 163,034 shares | 2.11% | -130.00K(-44.4%)Reduced | SEC filing ↗ May 16, 2025 | ▾ |
| 07 | SUSQUEHANNA INTERNATIONAL GROUP, LLP CIK 1446194 · View history | $2.72M 107,427 shares | 0.00% | +107.43KNew | SEC filing ↗ May 14, 2025 | ▾ |
| 08 | CITADEL ADVISORS LLC CIK 1423053 · View history | $2.67M 105,774 shares | 0.00% | +93.46K(+759.1%)Added | SEC filing ↗ May 15, 2025 | ▾ |
| 09 | BlackRock, Inc. CIK 2012383 · View history | $2.45M 96,947 shares | 0.00% | +95.42K(+6248.9%)Added | SEC filing ↗ May 2, 2025 | ▾ |
| 10 | O'SHAUGHNESSY ASSET MANAGEMENT, LLC CIK 1423442 · View history | $2.04M 80,570 shares | 0.02% | +7.70K(+10.6%)Added | SEC filing ↗ May 13, 2025 | ▾ |
| 11 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $1.93M 76,349 shares | 0.00% | +76.35KNew | SEC filing ↗ May 13, 2025 | ▾ |
| 12 | MILLENNIUM MANAGEMENT LLC CIK 1273087 · View history | $1.47M 58,200 shares | 0.00% | +58.20KNew | SEC filing ↗ May 15, 2025 | ▾ |
| 13 | TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history | $1.37M 54,261 shares | 0.00% | +54.26KNew | SEC filing ↗ May 15, 2025 | ▾ |
| 14 | NAVELLIER & ASSOCIATES INC CIK 872163 · View history | $1.10M 39,666 shares | 0.15% | +39.67KNew | SEC filing ↗ May 6, 2025 | ▾ |
| 15 | Valiant Capital Management, L.P. CIK 1452689 · View history | $1.10M 43,605 shares | 0.12% | +8.15K(+23.0%)Added | SEC filing ↗ May 15, 2025 | ▾ |
| 16 | Independent Advisor Alliance CIK 1696899 · View history | $1.09M 42,940 shares | 0.04% | +42.94KNew | SEC filing ↗ May 12, 2025 | ▾ |
| 17 | RITHOLTZ WEALTH MANAGEMENT CIK 1698218 · View history | $1.01M 39,855 shares | 0.03% | +39.85KNew | SEC filing ↗ Apr 17, 2025 | ▾ |
| 18 | CORSAIR CAPITAL MANAGEMENT, L.P. CIK 1276470 · Amended · View history | $929.47K 36,767 shares | 0.24% | +20.77K(+129.8%)Added | SEC filing ↗ Apr 21, 2026 | ▾ |
| 19 | BURNEY CO/ CIK 940445 · View history | $856.74K 33,890 shares | 0.03% | +33.89KNew | SEC filing ↗ May 6, 2025 | ▾ |
| 20 | CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · Amended · View history | $782.29K 30,945 shares | 0.00% | +30.95KNew | SEC filing ↗ Sep 15, 2025 | ▾ |
Showing 20 / 67 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 67 reporting institutions.
This page includes 20 of 67 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 67 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":"73933G202","quarter":"2025Q1","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.