Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
356 institutional managers reported holding MMS for the quarter ended Mar 31, 2026. Reported positions total over 95% of shares outstanding; the top 10 hold 62%. 52 opened new positions; 72 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| FMR (Fidelity) | 8.18M | 14.98% | $524.4M | unchanged | ≤2013 |
| BlackRock | 7.52M | 13.78% | $482.2M | trimmed -12.8% | ≤2013 |
| Vanguard Group | 6.39M | 11.71% | $409.7M | added +2.4% | ≤2013 |
| State Street | 2.46M | 4.50% | $157.7M | trimmed -1.2% | ≤2013 |
| Dimensional Fund Advisors | 2.11M | 3.86% | $135.1M | added +7.2% | ≤2013 |
| Fuller & Thaler Asset Management, INC. | 2.08M | 3.81% | $133.5M | added +31.2% | 2016 Q3 |
| Mackenzie Financial CORP | 1.58M | 2.89% | $101.2M | trimmed -16.1% | 2015 Q4 |
| Geode Capital | 1.50M | 2.74% | $96.0M | added +1.1% | ≤2013 |
| Van Berkom & Associates INC. | 1.17M | 2.15% | $75.2M | added +3.7% | ≤2013 |
| Allianz Asset Management GmbH | 894.9k | 1.64% | $57.4M | added +47.2% | 2021 Q1 |
| Reinhart Partners, LLC. | 855.1k | 1.57% | $54.8M | added +17.9% | 2019 Q4 |
| River Road Asset Management, LLC | 826.2k | 1.51% | $53.0M | unchanged | 2025 Q2 |
| UBS | 802.3k | 1.47% | $51.4M | added +11.9% | ≤2013 |
| Sio Capital Management, LLC | 768.8k | 1.41% | $49.3M | added +53.7% | 2024 Q3 |
| Charles Schwab Investment Management | 716.9k | 1.31% | $46.0M | trimmed -2.4% | ≤2013 |
| Stephens Investment Management Group LLC | 716.4k | 1.31% | $45.9M | unchanged | 2013 Q3 |
| Northern Trust | 693.0k | 1.27% | $44.4M | trimmed -0.8% | ≤2013 |
| Boston Partners | 669.1k | 1.23% | $42.9M | trimmed -24% | 2025 Q1 |
| Federated Hermes, INC. | 609.9k | 1.12% | $39.1M | added +3.2% | ≤2013 |
| Bank OF America CORP /DE/ | 563.5k | 1.03% | $36.1M | trimmed -19.6% | ≤2013 |
| BNY Mellon | 518.7k | 0.95% | $33.3M | unchanged | ≤2013 |
| Jupiter Asset Management LTD | 484.4k | 0.89% | $31.1M | opened | 2026 Q1 |
| Goldman Sachs | 480.6k | 0.88% | $30.8M | trimmed -17.7% | ≤2013 |
| Walleye Capital LLC | 428.6k | 0.79% | $27.5M | added +115.7% | 2024 Q1 |
| Qube Research & Technologies LTD | 398.1k | 0.73% | $25.5M | added +14.9% | 2023 Q2 |
| Royce & Associates | 372.5k | 0.68% | $23.9M | added +234.4% | 2025 Q4 |
| Morgan Stanley | 354.4k | 0.65% | $22.7M | trimmed -23.7% | ≤2013 |
| Fort Washington Investment Advisors INC /OH/ | 350.3k | 0.64% | $22.5M | added +1.9% | 2017 Q4 |
| Nuveen | 339.1k | 0.62% | $21.7M | trimmed -36.5% | 2019 Q1 |
| William Blair Investment Management, LLC | 324.2k | 0.59% | $20.8M | added +3.4% | 2022 Q1 |
| Lord, Abbett & CO. LLC | 309.7k | 0.57% | $19.9M | opened | 2026 Q1 |
| AQR Capital | 294.5k | 0.54% | $18.9M | trimmed -30.6% | ≤2013 |
| Wellington Management | 290.6k | 0.53% | $18.6M | trimmed -19.7% | 2024 Q1 |
| LSV Asset Management | 284.7k | 0.52% | $18.3M | added +74% | 2025 Q1 |
| Deutsche Bank AG\ | 270.7k | 0.50% | $17.4M | added +2% | ≤2013 |
| Public Employees Retirement Association OF Colorado | 270.6k | 0.50% | $17.4M | unchanged | ≤2013 |
| Principal Financial Group INC | 226.4k | 0.41% | $14.5M | added +28.8% | ≤2013 |
| Rice Hall James & Associates, LLC | 222.9k | 0.41% | $14.3M | added +4.2% | 2014 Q3 |
| Victory Capital Management INC | 221.4k | 0.41% | $14.2M | added +188.3% | 2015 Q3 |
| Point72 | 203.1k | 0.37% | $13.0M | trimmed -72.1% | 2025 Q1 |
| Invesco | 181.9k | 0.33% | $11.7M | added +16.8% | ≤2013 |
| Rhumbline Advisers | 176.3k | 0.32% | $11.3M | added +2.1% | ≤2013 |
| ExodusPoint | 171.3k | 0.31% | $11.0M | opened | 2025 Q3 |
| Barclays PLC | 170.2k | 0.31% | $10.9M | trimmed -34.2% | ≤2013 |
| D. E. Shaw | 158.9k | 0.29% | $10.2M | added +22.8% | 2018 Q1 |
| Allspring Global Investments Holdings, LLC | 154.0k | 0.28% | $9.9M | trimmed -63% | 2021 Q4 |
| BNP Paribas Financial Markets | 151.0k | 0.28% | $9.7M | trimmed -52.2% | 2014 Q2 |
| Clark Capital Management Group, INC. | 144.2k | 0.26% | $9.2M | trimmed -11.1% | 2025 Q1 |
| Public Sector Pension Investment Board | 141.3k | 0.26% | $9.1M | added +25.4% | 2025 Q1 |
| Russell Investments Group, LTD. | 137.1k | 0.25% | $8.8M | trimmed -15.7% | 2016 Q4 |
Largest 50 of 356 shown; the full ranked, searchable register is at boothcheck.com/holders/MMS. 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.