Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
342 institutional managers reported holding MRCY for the quarter ended Mar 31, 2026. Reported positions total over 95% of shares outstanding; the top 10 hold 55%. 49 opened new positions; 46 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 8.92M | 15.01% | $651.1M | added +3.6% | ≤2013 |
| Vanguard Group | 5.75M | 9.68% | $419.7M | added +2% | ≤2013 |
| JANA Partners (focused) | 4.11M | 6.91% | $299.8M | trimmed -17.2% | 2021 Q4 |
| State Street | 3.87M | 6.51% | $282.2M | added +12.9% | ≤2013 |
| Invesco | 2.44M | 4.11% | $178.2M | added +27.8% | ≤2013 |
| Conestoga Capital Advisors, LLC | 1.92M | 3.23% | $140.0M | trimmed -11.8% | 2018 Q2 |
| T. Rowe Price Investment Management, INC. | 1.58M | 2.66% | $115.3M | added +501.3% | 2025 Q2 |
| Geode Capital | 1.53M | 2.57% | $111.4M | added +11.5% | ≤2013 |
| Dimensional Fund Advisors | 1.23M | 2.07% | $89.6M | trimmed -16.8% | ≤2013 |
| Goldman Sachs | 1.20M | 2.02% | $87.7M | added +3.9% | ≤2013 |
| First Trust Advisors LP | 1.16M | 1.95% | $84.7M | trimmed -9.3% | 2015 Q3 |
| T. Rowe Price | 1.03M | 1.73% | $75.1M | added +18.5% | 2017 Q1 |
| Ameriprise Financial INC | 991.8k | 1.67% | $72.4M | trimmed -23.1% | ≤2013 |
| Fisher Investments | 980.4k | 1.65% | $71.6M | added +13.9% | 2024 Q4 |
| Neuberger Berman Group LLC | 910.4k | 1.53% | $66.5M | trimmed -11.6% | ≤2013 |
| FMR (Fidelity) | 903.7k | 1.52% | $66.0M | trimmed -21.6% | 2017 Q4 |
| Mirae Asset Global Etfs Holdings LTD. | 862.4k | 1.45% | $62.9M | added +43.8% | 2024 Q2 |
| VAN ECK Associates CORP | 851.1k | 1.43% | $62.1M | added +17.3% | 2023 Q1 |
| Raymond James Financial INC | 794.0k | 1.34% | $58.0M | added +12.1% | 2017 Q1 |
| Wellington Management | 755.5k | 1.27% | $55.1M | opened | 2026 Q1 |
| Jennison Associates LLC | 688.1k | 1.16% | $50.2M | added +52.9% | 2025 Q3 |
| Morgan Stanley | 671.3k | 1.13% | $49.0M | trimmed -8.1% | 2013 Q4 |
| Loomis Sayles & CO L P | 645.9k | 1.09% | $47.1M | trimmed -24.2% | 2018 Q4 |
| Bamco INC /NY/ | 645.1k | 1.09% | $47.1M | trimmed -22.8% | 2015 Q1 |
| Lord, Abbett & CO. LLC | 642.5k | 1.08% | $46.9M | added +4.3% | 2025 Q2 |
| Charles Schwab Investment Management | 636.0k | 1.07% | $46.4M | unchanged | ≤2013 |
| Voya Investment Management LLC | 609.3k | 1.02% | $44.5M | added +19.2% | ≤2013 |
| Emerald Advisers, LLC | 595.3k | 1.00% | $43.5M | added +12.1% | 2025 Q2 |
| Kennedy Capital Management LLC | 589.2k | 0.99% | $43.0M | trimmed -12.1% | 2024 Q3 |
| American Century Companies INC | 582.9k | 0.98% | $42.5M | added +144% | 2015 Q1 |
| Snyder Capital Management L P | 580.7k | 0.98% | $42.4M | trimmed -22.4% | 2018 Q2 |
| Allspring Global Investments Holdings, LLC | 573.5k | 0.96% | $41.9M | trimmed -23.9% | 2025 Q2 |
| Northern Trust | 548.1k | 0.92% | $40.0M | added +5.8% | ≤2013 |
| Royal Bank OF Canada | 532.7k | 0.90% | $38.9M | trimmed -17.3% | ≤2013 |
| Franklin Resources | 453.6k | 0.76% | $33.1M | added +117.6% | 2025 Q2 |
| Bessemer Group INC | 449.7k | 0.76% | $32.8M | added +12.6% | 2020 Q2 |
| Oberweis Asset Management INC/ | 391.0k | 0.66% | $28.5M | trimmed -5.6% | 2025 Q1 |
| Emerald Mutual Fund Advisers Trust | 375.5k | 0.63% | $27.4M | added +11.7% | 2025 Q2 |
| SEI Investments CO | 371.0k | 0.62% | $27.1M | trimmed -1.9% | 2014 Q4 |
| Artisan Partners | 354.3k | 0.60% | $25.9M | opened | 2026 Q1 |
| UBS | 349.2k | 0.59% | $25.5M | trimmed -4.8% | ≤2013 |
| William Blair Investment Management, LLC | 327.3k | 0.55% | $23.9M | trimmed -66.7% | 2016 Q1 |
| BNY Mellon | 314.4k | 0.53% | $22.9M | trimmed -2.5% | ≤2013 |
| Silvercrest Asset Management Group LLC | 310.2k | 0.52% | $22.6M | added +2.6% | 2025 Q2 |
| MetLife Investment Management, LLC | 295.7k | 0.50% | $21.6M | added +10.2% | 2017 Q4 |
| Bank OF America CORP /DE/ | 294.9k | 0.50% | $21.5M | added +19.5% | ≤2013 |
| Driehaus Capital Management LLC | 294.6k | 0.50% | $21.5M | trimmed -3.3% | 2025 Q2 |
| Nomura Asset Management International INC. | 294.4k | 0.49% | $21.5M | added +64.8% | 2025 Q3 |
| Citadel Advisors | 292.9k | 0.49% | $21.4M | added +180.6% | 2017 Q4 |
| Fifth Third Bancorp | 267.1k | 0.45% | $19.5M | added +22232.9% | 2015 Q1 |
Largest 50 of 342 shown; the full ranked, searchable register is at boothcheck.com/holders/MRCY. Related filers are grouped using the filings' own included-manager declarations. Historically, several managers opening new positions in the same quarter said almost nothing about the quarter that followed (59,118 cases since 2013). A filed record, not a forecast. Nothing here is investment advice.