Mercury Systems Inc
Ownership
Ownership Structure
Who owns Mercury Systems Inc (MRCY)? This page shows the largest institutions and funds, the ownership structure and the latest insider transactions. 92.3% of the shares are freely tradable; institutional investors hold 113.3%.
Largest Shareholders
Institutions
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| BlackRock Inc | 14.83 | 8,920,325 | +3.6 | 03/31/2026 |
| Jana Partners Management LP | 6.58 | 3,958,849 | -3.6 | 06/30/2026 |
| State Street Corp | 6.43 | 3,865,719 | +12.9 | 03/31/2026 |
| Vanguard Portfolio Management, LLC | 4.84 | 2,910,904 | +0.0 | 03/31/2026 |
| Amvescap Plc. | 4.06 | 2,441,578 | +27.8 | 03/31/2026 |
| Vanguard Capital Management, LLC | 4.00 | 2,403,818 | +0.0 | 03/31/2026 |
| T. Rowe Price Investment Management,Inc. | 2.63 | 1,579,832 | -12.5 | 03/31/2026 |
Funds
| Name | Stake (%) | Shares | Change (%) | Date |
|---|---|---|---|---|
| iShares Core S&P Small-Cap ETF | 5.36 | 3,220,761 | +0.0 | 08/31/2026 |
| Vanguard MStar Total Stk Mkt Idx Invest | 2.86 | 1,722,349 | +0.3 | 07/31/2026 |
| First Trust RBA Amer Indl RenaisTM ETF | 2.68 | 1,611,497 | +0.1 | 08/31/2026 |
Largest reported positions according to regulatory filings; stake as a percentage of shares outstanding, change versus the previous filing. Source: fundamentals data.
Insider holdings
| Person | Role | Shares | Value | As of | Type |
|---|---|---|---|---|---|
| Ballhaus William L | Chairman, President & CEO | 361,822 | 30,863,444 $ | Aug 26, 2026 | direct |
| Farnsworth David E. | EVP, CFO | 117,967 | 10,062,585 $ | Aug 20, 2026 | direct |
| Kupinsky Stuart | EVP, CLO & Corp Sec | 56,352 | 4,806,826 $ | Aug 21, 2026 | direct |
| Nearhos Barry R | Director | 31,494 | 2,686,438 $ | Jul 16, 2026 | direct |
| Ratner Steven | EVP, CHRO | 19,275 | 1,644,158 $ | Aug 21, 2026 | both |
| Munro Douglas | SVP, CAO | 12,982 | 1,107,365 $ | Aug 20, 2026 | direct |
Holdings as of each person's most recent SEC Form 4 filing — excluding options and RSUs, which are not shares yet. Holdings may have changed between two filings.
Insiders
Insider Transactions
| Date | Person | Role | Type | Shares | Price | Value |
|---|---|---|---|---|---|---|
| Sep 3, 2026 | Ratner Steven | EVP, CHRO | Sell | 4,000 | 84.51 | 338,030 |
| Aug 26, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 10,814 | 89.74 | 970,492 |
| Aug 26, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 38,276 | 88.91 | 3,403,234 |
| Aug 26, 2026 | Ballhaus William L | Chairman, President & CEO | Other | 68,476 | 43.00 | 2,944,468 |
| Aug 25, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 3,448 | 87.99 | 303,400 |
| Aug 25, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 107,628 | 87.09 | 9,373,215 |
| Aug 25, 2026 | Ballhaus William L | Chairman, President & CEO | Other | 153,676 | 43.00 | 6,608,068 |
| Aug 24, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 2,738 | 90.60 | 248,063 |
| Aug 24, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 105,471 | 89.47 | 9,436,807 |
| Aug 24, 2026 | Ballhaus William L | Chairman, President & CEO | Other | 11,348 | 43.00 | 487,964 |
| Aug 24, 2026 | Ballhaus William L | Chairman, President & CEO | Other | 140,650 | 42.00 | 5,907,300 |
| Aug 21, 2026 | Ratner Steven | EVP, CHRO | Sell | 356 | 91.36 | 32,524 |
| Aug 21, 2026 | Kupinsky Stuart | EVP, CLO & Corp Sec | Sell | 1,000 | 95.23 | 95,230 |
| Aug 21, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 204 | 93.51 | 19,076 |
| Aug 21, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 64,796 | 92.40 | 5,987,410 |
| Aug 21, 2026 | Ballhaus William L | Chairman, President & CEO | Other | 92,850 | 42.00 | 3,899,700 |
| Aug 20, 2026 | Munro Douglas | SVP, CAO | Sell | 109 | 97.67 | 10,646 |
| Aug 20, 2026 | Ratner Steven | EVP, CHRO | Sell | 1,026 | 97.67 | 100,213 |
| Aug 20, 2026 | Farnsworth David E. | EVP, CFO | Sell | 6,612 | 97.67 | 645,817 |
| Aug 20, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 22,010 | 97.67 | 2,149,792 |
| Aug 19, 2026 | Munro Douglas | SVP, CAO | Sell | 548 | 100.31 | 54,968 |
| Aug 19, 2026 | Ratner Steven | EVP, CHRO | Sell | 2,187 | 100.31 | 219,369 |
| Aug 19, 2026 | Kupinsky Stuart | EVP, CLO & Corp Sec | Sell | 1,308 | 100.31 | 131,200 |
| Aug 19, 2026 | Farnsworth David E. | EVP, CFO | Sell | 8,155 | 100.31 | 817,995 |
| Aug 19, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 26,802 | 100.31 | 2,688,401 |
| Aug 18, 2026 | Munro Douglas | SVP, CAO | Sell | 494 | 111.36 | 55,011 |
| Aug 18, 2026 | Ratner Steven | EVP, CHRO | Sell | 1,971 | 111.36 | 219,486 |
| Aug 18, 2026 | Kupinsky Stuart | EVP, CLO & Corp Sec | Sell | 1,178 | 111.36 | 131,179 |
| Aug 18, 2026 | Farnsworth David E. | EVP, CFO | Sell | 7,347 | 111.36 | 818,145 |
| Aug 18, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 24,144 | 111.36 | 2,688,620 |
| Aug 17, 2026 | Munro Douglas | SVP, CAO | Sell | 404 | 109.95 | 44,420 |
| Aug 17, 2026 | Ratner Steven | EVP, CHRO | Sell | 1,084 | 109.95 | 119,187 |
| Aug 17, 2026 | Kupinsky Stuart | EVP, CLO & Corp Sec | Sell | 1,195 | 109.95 | 131,391 |
| Aug 17, 2026 | Farnsworth David E. | EVP, CFO | Sell | 1,345 | 109.95 | 147,884 |
| Aug 17, 2026 | Ballhaus William L | Chairman, President & CEO | Sell | 3,536 | 109.95 | 388,786 |
| Aug 14, 2026 | Ratner Steven | EVP, CHRO | Other | 2,695 | 0.00 | – |
| Aug 14, 2026 | Kupinsky Stuart | EVP, CLO & Corp Sec | Other | 6,977 | 0.00 | – |
| Aug 14, 2026 | Farnsworth David E. | EVP, CFO | Other | 16,275 | 0.00 | – |
| Aug 14, 2026 | Ballhaus William L | Chairman, President & CEO | Other | 70,287 | 0.00 | – |
| Jul 16, 2026 | Nearhos Barry R | Director | Other | 170 | 0.00 | – |
Reportable transactions by officers and major shareholders from SEC Form 4 filings. "Other" includes things like stock grants and option exercises without a buy/sell character. View all insider transactions →
Data as of: September 18, 2026 · Source: fundamental data & SEC filings (annual and quarterly reports, 10-K/10-Q)
Note: pure fact-based analysis, not investment advice and not a solicitation to buy or sell. All figures without guarantee.