MERCURY SYSTEMS INC MRCY
CIK 0001049521 · CUSIP 589378108
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 | BlackRock, Inc. CIK 2012383 · View history | $656.13M 8,477,158 shares | 0.01% | +228.19K(+2.8%)Added | SEC filing ↗ Nov 12, 2025 | ▾ |
| 02 | JANA Partners Management, LP CIK 1998597 · View history | $461.26M 5,959,481 shares | 22.33% | -793.93K(-11.8%)Reduced | SEC filing ↗ Nov 14, 2025 | ▾ |
| 03 | VANGUARD GROUP INC CIK 102909 · View history | $443.58M 5,731,033 shares | 0.01% | +221.09K(+4.0%)Added | SEC filing ↗ Nov 7, 2025 | ▾ |
| 04 | STATE STREET CORP CIK 93751 · View history | $236.48M 3,055,358 shares | 0.01% | -191.22K(-5.9%)Reduced | SEC filing ↗ Nov 14, 2025 | ▾ |
| 05 | WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC CIK 1644956 · View history | $192.57M 2,487,957 shares | 0.50% | -2.21M(-47.0%)Reduced | SEC filing ↗ Nov 12, 2025 | ▾ |
| 06 | Conestoga Capital Advisors, LLC CIK 1163744 · View history | $176.46M 2,279,909 shares | 2.83% | -279.03K(-10.9%)Reduced | SEC filing ↗ Oct 24, 2025 | ▾ |
| 07 | DIMENSIONAL FUND ADVISORS LP CIK 354204 · View history | $134.96M 1,743,814 shares | 0.03% | -87.56K(-4.8%)Reduced | SEC filing ↗ Nov 12, 2025 | ▾ |
| 08 | FIRST TRUST ADVISORS LP CIK 1125816 · View history | $118.64M 1,532,822 shares | 0.09% | +751.81K(+96.3%)Added | SEC filing ↗ Nov 12, 2025 | ▾ |
| 09 | Invesco Ltd. CIK 914208 · View history | $118.22M 1,527,443 shares | 0.02% | +943.74K(+161.7%)Added | SEC filing ↗ Nov 13, 2025 | ▾ |
| 10 | T. Rowe Price Investment Management, Inc. CIK 1897612 · View history | $117.78M 1,521,669 shares | 0.07% | +552.85K(+57.1%)Added | SEC filing ↗ Nov 14, 2025 | ▾ |
| 11 | FMR LLC CIK 315066 · View history | $114.82M 1,483,473 shares | 0.01% | +314.38K(+26.9%)Added | SEC filing ↗ Nov 13, 2025 | ▾ |
| 12 | GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history | $102.30M 1,321,485 shares | 0.01% | +56.48K(+4.5%)Added | SEC filing ↗ Nov 12, 2025 | ▾ |
| 13 | BAMCO INC /NY/ CIK 1017918 · View history | $100.25M 1,295,284 shares | 0.27% | +60.48K(+4.9%)Added | SEC filing ↗ Nov 14, 2025 | ▾ |
| 14 | GOLDMAN SACHS GROUP INC CIK 886982 · View history | $95.93M 1,239,435 shares | 0.01% | +182.52K(+17.3%)Added | SEC filing ↗ Nov 14, 2025 | ▾ |
| 15 | NEUBERGER BERMAN GROUP LLC CIK 1465109 · View history | $80.90M 1,046,469 shares | 0.06% | -9.95K(-0.9%)Reduced | SEC filing ↗ Nov 12, 2025 | ▾ |
| 16 | LOOMIS SAYLES & CO L P CIK 312348 · View history | $68.47M 884,615 shares | 0.08% | -108.00K(-10.9%)Reduced | SEC filing ↗ Nov 13, 2025 | ▾ |
| 17 | MORGAN STANLEY CIK 895421 · Amended · View history | $67.83M 876,397 shares | 0.00% | -51.77K(-5.6%)Reduced | SEC filing ↗ May 27, 2026 | ▾ |
| 18 | Fisher Asset Management, LLC CIK 850529 · View history | $67.75M 875,279 shares | 0.02% | +153.95K(+21.3%)Added | SEC filing ↗ Nov 12, 2025 | ▾ |
| 19 | PRICE T ROWE ASSOCIATES INC /MD/ CIK 80255 · View history | $67.03M 866,077 shares | 0.01% | +822.09K(+1868.9%)Added | SEC filing ↗ Nov 14, 2025 | ▾ |
| 20 | SNYDER CAPITAL MANAGEMENT L P CIK 1050477 · View history | $60.48M 781,404 shares | 1.14% | -176.50K(-18.4%)Reduced | SEC filing ↗ Nov 12, 2025 | ▾ |
Showing 20 / 326 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 326 reporting institutions.
This page includes 20 of 326 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 326 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":"589378108","quarter":"2025Q3","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.