Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
360 institutional managers reported holding SIGI for the quarter ended Mar 31, 2026. Together they hold about 84% of shares outstanding; the top 10 hold 49%. 57 opened new positions; 51 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| BlackRock | 7.50M | 12.40% | $565.6M | unchanged | ≤2013 |
| Vanguard Group | 6.66M | 11.01% | $502.4M | unchanged | ≤2013 |
| AQR Capital | 3.94M | 6.51% | $296.9M | trimmed -3% | 2015 Q1 |
| FMR (Fidelity) | 2.50M | 4.13% | $188.6M | trimmed -49.3% | 2018 Q3 |
| State Street | 2.33M | 3.85% | $175.4M | trimmed -1.1% | ≤2013 |
| Geode Capital | 1.71M | 2.83% | $128.9M | added +2.9% | ≤2013 |
| First Trust Advisors LP | 1.38M | 2.29% | $104.2M | added +33.3% | 2013 Q3 |
| Dimensional Fund Advisors | 1.36M | 2.25% | $102.5M | added +3.4% | ≤2013 |
| American Century Companies INC | 1.27M | 2.10% | $95.6M | added +107.8% | 2020 Q1 |
| Nomura Asset Management International INC. | 1.20M | 1.98% | $90.3M | trimmed -11.4% | 2025 Q4 |
| Morgan Stanley | 1.12M | 1.85% | $84.6M | trimmed -2% | ≤2013 |
| Charles Schwab Investment Management | 893.8k | 1.48% | $67.4M | unchanged | ≤2013 |
| Northern Trust | 869.8k | 1.44% | $65.6M | unchanged | ≤2013 |
| Janus Henderson | 784.2k | 1.30% | $59.1M | unchanged | 2020 Q2 |
| Bank OF America CORP /DE/ | 759.1k | 1.25% | $57.3M | added +2.5% | ≤2013 |
| Frontier Capital Management CO LLC | 729.7k | 1.21% | $55.0M | added +18.6% | 2025 Q2 |
| Goldman Sachs | 603.0k | 1.00% | $45.5M | added +21.4% | ≤2013 |
| Franklin Resources | 555.3k | 0.92% | $41.9M | added +0.5% | 2019 Q4 |
| Jacobs Levy Equity Management, INC | 549.6k | 0.91% | $41.5M | trimmed -18.6% | 2024 Q3 |
| Raymond James Financial INC | 485.1k | 0.80% | $36.6M | added +14.8% | 2014 Q4 |
| Verition Fund Management | 484.0k | 0.80% | $36.5M | added +9.9% | 2023 Q3 |
| BNY Mellon | 482.9k | 0.80% | $36.4M | unchanged | ≤2013 |
| MFS Investment Management | 476.5k | 0.79% | $35.9M | trimmed -1.2% | 2020 Q3 |
| Qube Research & Technologies LTD | 468.7k | 0.78% | $35.3M | opened | 2026 Q1 |
| Vaughan Nelson Investment Management, L.p. | 464.2k | 0.77% | $35.0M | trimmed -56.9% | 2021 Q2 |
| Boston Trust Walden CORP | 425.5k | 0.70% | $32.1M | trimmed -10.7% | 2020 Q4 |
| Arrowstreet Capital | 420.1k | 0.69% | $31.7M | added +332.2% | 2025 Q3 |
| UBS | 392.4k | 0.65% | $29.6M | unchanged | ≤2013 |
| William Blair Investment Management, LLC | 370.4k | 0.61% | $27.9M | added +3.6% | 2025 Q1 |
| Systematic Financial Management LP | 329.5k | 0.55% | $24.9M | added +0.5% | ≤2013 |
| Nuveen | 324.7k | 0.54% | $24.5M | trimmed -14.2% | 2019 Q2 |
| Deutsche Bank AG\ | 305.1k | 0.50% | $23.0M | trimmed -19.8% | 2013 Q3 |
| MetLife Investment Management, LLC | 262.5k | 0.43% | $19.8M | trimmed -11.6% | 2017 Q4 |
| Principal Financial Group INC | 253.2k | 0.42% | $19.1M | added +92.2% | ≤2013 |
| Tributary Capital Management, LLC | 250.6k | 0.41% | $18.9M | trimmed -2.3% | ≤2013 |
| Invesco | 226.1k | 0.37% | $17.1M | added +1.7% | ≤2013 |
| Algert Global LLC | 212.7k | 0.35% | $16.0M | trimmed -5.7% | 2024 Q1 |
| Rhumbline Advisers | 197.1k | 0.33% | $14.9M | added +2.8% | ≤2013 |
| Voloridge Investment Management | 192.2k | 0.32% | $14.5M | trimmed -8.1% | 2024 Q2 |
| Kennedy Capital Management LLC | 186.9k | 0.31% | $14.1M | trimmed -1.5% | 2024 Q2 |
| ExodusPoint | 184.8k | 0.31% | $13.9M | opened | 2026 Q1 |
| Russell Investments Group, LTD. | 176.8k | 0.29% | $13.3M | trimmed -12% | 2016 Q4 |
| Healthcare OF Ontario Pension Plan Trust Fund | 173.9k | 0.29% | $13.1M | trimmed -4.6% | 2023 Q4 |
| Gillson Capital LP | 160.7k | 0.27% | $12.1M | added +107.4% | 2025 Q4 |
| Lighthouse Investment Partners, LLC | 158.6k | 0.26% | $12.0M | opened | 2025 Q3 |
| CalPERS | 157.1k | 0.26% | $11.8M | trimmed -2.2% | ≤2013 |
| Trexquant Investment LP | 151.1k | 0.25% | $11.4M | added +164.4% | 2024 Q4 |
| Citadel Advisors | 120.9k | 0.20% | $9.1M | added +145.5% | 2021 Q4 |
| Swiss National Bank | 119.4k | 0.20% | $9.0M | unchanged | ≤2013 |
| D. E. Shaw | 115.2k | 0.19% | $8.7M | trimmed -6% | 2023 Q2 |
Largest 50 of 360 shown; the full ranked, searchable register is at boothcheck.com/holders/SIGI. 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.