Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
348 institutional managers reported holding OPEN for the quarter ended Mar 31, 2026. Together they hold about 49% of shares outstanding; the top 10 hold 34%. 68 opened new positions; 74 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| Vanguard Group | 111.74M | 11.65% | $522.9M | added +1.3% | 2021 Q1 |
| Morgan Stanley | 102.77M | 10.71% | $481.0M | added +99.2% | 2020 Q4 |
| BlackRock | 18.64M | 1.94% | $87.2M | added +4.1% | 2021 Q1 |
| Jane Street | 14.72M | 1.53% | $68.9M | added +6.1% | 2020 Q4 |
| American Century Companies INC | 14.20M | 1.48% | $66.5M | trimmed -1% | 2025 Q3 |
| Lennar CORP /New/ (focused) | 13.53M | 1.41% | $63.3M | trimmed -28% | 2025 Q4 |
| Geode Capital | 12.33M | 1.28% | $57.7M | added +6.2% | 2020 Q4 |
| Renaissance Technologies | 11.81M | 1.23% | $55.3M | trimmed -70% | 2022 Q2 |
| D. E. Shaw | 11.23M | 1.17% | $52.6M | added +74.2% | 2023 Q3 |
| Charles Schwab Investment Management | 11.23M | 1.17% | $52.6M | trimmed -3.9% | 2021 Q1 |
| Millennium Management | 10.84M | 1.13% | $50.7M | added +123% | 2020 Q4 |
| Qube Research & Technologies LTD | 10.16M | 1.06% | $47.5M | added +682.9% | 2025 Q2 |
| Dimensional Fund Advisors | 9.07M | 0.95% | $42.5M | added +96.7% | 2023 Q1 |
| UBS | 8.69M | 0.91% | $40.7M | added +25% | 2020 Q4 |
| Citadel Advisors | 8.04M | 0.84% | $37.6M | added +5.4% | 2021 Q1 |
| Two Sigma | 6.77M | 0.71% | $31.7M | added +65.9% | 2022 Q4 |
| State Street | 5.98M | 0.62% | $28.0M | trimmed -3.4% | 2021 Q1 |
| Marex Group plc | 4.93M | 0.51% | $23.1M | trimmed -15.2% | 2022 Q4 |
| Voloridge Investment Management | 4.31M | 0.45% | $20.2M | added +2.7% | 2025 Q3 |
| Trexquant Investment LP | 4.07M | 0.42% | $19.0M | added +126.9% | 2025 Q3 |
| Goldman Sachs | 3.95M | 0.41% | $18.5M | added +151.3% | 2021 Q1 |
| Hennessy Advisors INC | 3.73M | 0.39% | $17.5M | trimmed -9.5% | 2025 Q3 |
| Susquehanna International Group | 3.34M | 0.35% | $15.6M | added +3391.8% | 2020 Q4 |
| Invesco | 3.06M | 0.32% | $14.3M | trimmed -17.7% | 2021 Q2 |
| IEQ Capital, LLC | 2.94M | 0.31% | $13.8M | unchanged | 2021 Q2 |
| Amundi | 2.60M | 0.27% | $12.1M | added +4666.2% | 2025 Q4 |
| Northern Trust | 2.53M | 0.26% | $11.8M | added +31% | 2021 Q1 |
| Graham Capital Management, L.p. | 2.47M | 0.26% | $11.6M | trimmed -10.6% | 2025 Q4 |
| CPP Investment Board | 2.31M | 0.24% | $10.8M | added +305.7% | 2025 Q3 |
| Capital Fund Management S.a. | 2.25M | 0.23% | $10.5M | opened | 2026 Q1 |
| LPL Financial LLC | 2.08M | 0.22% | $9.7M | added +18.4% | 2020 Q4 |
| Kestra Private Wealth Services, LLC | 2.04M | 0.21% | $9.5M | added +24.6% | 2025 Q1 |
| BNP Paribas Financial Markets | 1.89M | 0.20% | $8.8M | trimmed -69.4% | 2024 Q4 |
| Swiss National Bank | 1.79M | 0.19% | $8.4M | unchanged | 2021 Q2 |
| Alpine Fox Capital LLC (focused) | 1.67M | 0.17% | $7.8M | added +6580.8% | 2025 Q4 |
| Brevan Howard Capital Management LP | 1.65M | 0.17% | $7.7M | added +4932% | 2024 Q4 |
| Prentice Capital Management, LP (focused) | 1.60M | 0.17% | $7.5M | added +189.9% | 2025 Q4 |
| Marshall Wace | 1.58M | 0.16% | $7.4M | opened | 2024 Q2 |
| Bank OF America CORP /DE/ | 1.48M | 0.15% | $6.9M | trimmed -8.1% | 2020 Q4 |
| GF Fund Management CO. LTD. | 1.30M | 0.14% | $6.1M | trimmed -1.3% | 2025 Q3 |
| Squarepoint Ops LLC | 1.18M | 0.12% | $5.5M | added +1486.5% | 2024 Q3 |
| IMC-Chicago, LLC | 1.03M | 0.11% | $4.8M | opened | 2024 Q2 |
| California State Teachers Retirement System | 1.00M | 0.10% | $4.7M | added +23.8% | 2021 Q2 |
| CAZ Investments LP (focused) | 872.5k | 0.09% | $4.1M | unchanged | 2021 Q2 |
| Susquehanna Portfolio Strategies, LLC | 712.6k | 0.07% | $3.3M | unchanged | 2025 Q3 |
| Legal & General Group PLC | 664.2k | 0.07% | $3.1M | trimmed -18.5% | 2021 Q2 |
| Alight Capital Management LP | 650.0k | 0.07% | $3.0M | added +225% | 2025 Q3 |
| Tudor Investment | 640.8k | 0.07% | $3.0M | trimmed -31.4% | 2024 Q4 |
| Intact Investment Management INC. | 615.8k | 0.06% | $2.9M | added +253% | 2025 Q4 |
| Fora Capital, LLC | 589.4k | 0.06% | $2.8M | trimmed -46.2% | 2025 Q3 |
Largest 50 of 348 shown; the full ranked, searchable register is at boothcheck.com/holders/OPEN. 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.