# MERCURY SYS INC COM

MERCURY SYS INC COM is a security (CUSIP 589378108) tracked across SEC portfolio filings. 386 institutional managers reported $4.8B on Form 13F as of 2026-06-30; 40 registered fund positions totaling $360.7M via N-PORT as of 2026-05-31.

## Summary

- Issuer: MERCURY SYS INC
- Class: COM
- CUSIP: 589378108
- Asset category: EC
- 13F holders: 386
- 13F value: $4.8B
- 13F period: 2026-06-30
- N-PORT fund positions: 40
- N-PORT value: $360.7M
- N-PORT report: 2026-05-31

## Top institutional holders (Form 13F)

_Showing 15 of 386 managers by value._

| Manager | Location | Value | Shares |
| --- | --- | --- | --- |
| BlackRock, Inc. | New York, NY | $1.1B | 9,370,902 |
| STATE STREET CORP | BOSTON, MA | $418.0M | 3,418,290 |
| [VANGUARD GROUP INC](https://search.stillhousedata.com/firm/105958) | Valley Forge, PA | $411.2M | 5,632,049 |
| Conestoga Capital Advisors, LLC | WAYNE, PA | $181.9M | 1,487,191 |
| [Fisher Asset Management, LLC](https://search.stillhousedata.com/firm/107342) | PLANO, TX | $115.5M | 944,069 |
| [GEODE CAPITAL MANAGEMENT, LLC](https://search.stillhousedata.com/firm/115504) | BOSTON, MA | $111.3M | 1,525,716 |
| DIMENSIONAL FUND ADVISORS LP | AUSTIN, TX | $89.5M | 1,227,975 |
| GOLDMAN SACHS GROUP INC | NEW YORK, NY | $87.6M | 1,201,112 |
| FIRST TRUST ADVISORS LP | Wheaton, IL | $84.6M | 1,160,775 |
| [EMERALD ADVISERS, LLC](https://search.stillhousedata.com/firm/107496) | LEOLA, PA | $78.1M | 638,682 |
| [SEGALL BRYANT & HAMILL, LLC](https://search.stillhousedata.com/firm/106505) | CHICAGO, IL | $68.2M | 934,824 |
| NEUBERGER BERMAN GROUP LLC | NEW YORK, NY | $66.3M | 910,418 |
| FMR LLC | BOSTON, MA | $65.9M | 903,668 |
| MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. | CENTRAL, K3 | $62.7M | 859,447 |
| RAYMOND JAMES FINANCIAL INC | ST. PETERSBURG, FL | $56.3M | 794,029 |

## Top fund holders (N-PORT)

_Showing 15 of 40 fund positions by value._

| Fund | Registrant | Value | % of fund |
| --- | --- | --- | --- |
| [Select Fund](https://search.stillhousedata.com/fund/S000006194) | American Century Mutual Funds, Inc. | $49.5M | 77.47% |
| [T. Rowe Price New Horizons Fund, Inc.](https://search.stillhousedata.com/fund/S000002106) | T. ROWE PRICE NEW HORIZONS FUND, INC. | $46.2M | 36.16% |
| [VANGUARD EXTENDED MARKET INDEX FUND](https://search.stillhousedata.com/fund/S000002841) | VANGUARD INDEX FUNDS | $43.0M | 5.27% |
| [T. Rowe Price Small-Cap Stock Fund, Inc.](https://search.stillhousedata.com/fund/S000002120) | T. ROWE PRICE SMALL-CAP STOCK FUND, INC. | $31.8M | 39.44% |
| [VANGUARD RUSSELL 2000 INDEX FUND](https://search.stillhousedata.com/fund/S000030003) | VANGUARD SCOTTSDALE FUNDS | $31.2M | 17.81% |
| [LORD ABBETT DEVELOPING GROWTH FUND INC](https://search.stillhousedata.com/fund/S000006834) | LORD ABBETT DEVELOPING GROWTH FUND, INC. | $25.7M | 115.60% |
| [T. Rowe Price Small-Cap Value Fund, Inc.](https://search.stillhousedata.com/fund/S000002121) | T. ROWE PRICE SMALL-CAP VALUE FUND, INC. | $21.6M | 23.46% |
| [PGIM Jennison Small Company Fund](https://search.stillhousedata.com/fund/S000004629) | Prudential Jennison Small Co Fund, Inc. | $17.8M | 55.95% |
| [Emerald Growth Fund](https://search.stillhousedata.com/fund/S000036390) | FINANCIAL INVESTORS TRUST | $17.8M | 126.22% |
| [T. Rowe Price Institutional Small-Cap Stock Fund](https://search.stillhousedata.com/fund/S000002094) | T. Rowe Price Equity Funds, Inc. | $17.3M | 39.99% |
| [CONESTOGA SMID CAP FUND](https://search.stillhousedata.com/fund/S000043859) | Conestoga Funds | $14.5M | 291.59% |
| [U.S. MICRO CAP PORTFOLIO](https://search.stillhousedata.com/fund/S000000948) | DFA INVESTMENT DIMENSIONS GROUP INC | $7.2M | 9.60% |
| [Master Small Cap Index Series](https://search.stillhousedata.com/fund/S000002716) | Quantitative Master Series LLC | $6.2M | 12.93% |
| [Optimum Small-Mid Cap Growth Fund](https://search.stillhousedata.com/fund/S000002424) | Optimum Fund Trust | $3.2M | 42.78% |
| [Columbia Variable Portfolio - Small Company Growth Fund](https://search.stillhousedata.com/fund/S000010658) | COLUMBIA FUNDS VARIABLE INSURANCE TRUST | $2.9M | 135.47% |

## More

- [This page as markdown (for LLM agents)](https://search.stillhousedata.com/security/589378108.md)
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Source: public SEC filing data via Adviser Search (https://search.stillhousedata.com).
Agents: this data is also queryable via MCP tools and read-only SQL — see https://search.stillhousedata.com/llms.txt.