Mar 31, 2026 filings. Quarterly 13F reports arrive up to 45 days after quarter end; this register is filed through May 29, 2026.
545 institutional managers reported holding SIRI for the quarter ended Mar 31, 2026. Together they hold about 73% of shares outstanding; the top 10 hold 52%. 111 opened new positions; 76 closed out. Complete ranked register from SEC 13F filings.
| manager | shares | % out | value (Mar 31, 2026 close) | change | held since |
|---|---|---|---|---|---|
| Berkshire Hathaway (focused) | 124.81M | 35.06% | $2.88B | unchanged | 2023 Q3 |
| Vanguard Group | 18.49M | 5.19% | $426.3M | added +0.8% | ≤2013 |
| BlackRock | 9.63M | 2.70% | $222.0M | trimmed -4.2% | ≤2013 |
| Dimensional Fund Advisors | 6.30M | 1.77% | $145.3M | added +262.1% | ≤2013 |
| Kontiki Capital Management (HK) LTD. (focused) | 5.70M | 1.60% | $131.4M | trimmed -4.5% | 2025 Q2 |
| Goldman Sachs | 3.91M | 1.10% | $90.2M | added +19.5% | ≤2013 |
| CPP Investment Board | 3.86M | 1.08% | $89.0M | added +105.9% | 2015 Q4 |
| Geode Capital | 3.71M | 1.04% | $85.5M | unchanged | ≤2013 |
| State Street | 3.55M | 1.00% | $81.8M | added +1.7% | ≤2013 |
| Citadel Advisors | 3.26M | 0.92% | $75.2M | added +312.7% | 2016 Q2 |
| LSV Asset Management | 3.22M | 0.90% | $74.3M | added +4.8% | 2024 Q4 |
| AQR Capital | 2.99M | 0.84% | $68.9M | added +106.1% | 2015 Q3 |
| Check Capital Management INC/CA (focused) | 2.94M | 0.83% | $67.9M | added +2% | 2024 Q3 |
| Gates Capital Management, INC. (focused) | 2.74M | 0.77% | $63.2M | opened | 2026 Q1 |
| Thompson Siegel & Walmsley LLC | 2.56M | 0.72% | $59.1M | added +10.9% | 2024 Q3 |
| Ameriprise Financial INC | 2.41M | 0.68% | $55.7M | added +1.7% | ≤2013 |
| BNY Mellon | 2.18M | 0.61% | $50.2M | added +7.8% | ≤2013 |
| Morgan Stanley | 2.16M | 0.61% | $49.7M | added +26% | ≤2013 |
| Seizert Capital Partners, LLC | 1.84M | 0.52% | $42.4M | trimmed -3.1% | 2024 Q3 |
| Hsbc Holdings PLC | 1.80M | 0.50% | $41.4M | trimmed -13.5% | ≤2013 |
| UBS | 1.80M | 0.50% | $41.4M | trimmed -15.7% | ≤2013 |
| Two Sigma | 1.78M | 0.50% | $41.0M | trimmed -29.4% | 2023 Q4 |
| Charles Schwab Investment Management | 1.74M | 0.49% | $40.1M | added +6.9% | ≤2013 |
| HRT Financial LP | 1.57M | 0.44% | $36.1M | added +3524.4% | 2023 Q4 |
| Private Management Group INC | 1.35M | 0.38% | $31.2M | unchanged | 2025 Q3 |
| Weitz Investment Management, INC. (focused) | 1.29M | 0.36% | $29.8M | trimmed -6.6% | 2024 Q3 |
| Gotham Asset Management | 1.24M | 0.35% | $28.6M | added +46.9% | 2021 Q3 |
| Tidal Investments LLC | 1.21M | 0.34% | $27.9M | trimmed -2% | 2021 Q1 |
| HBK Investments L P | 1.16M | 0.33% | $26.8M | trimmed -30.9% | 2024 Q2 |
| Wittenberg Investment Management, INC. | 1.11M | 0.31% | $25.5M | added +1.4% | 2024 Q2 |
| Northern Trust | 1.10M | 0.31% | $25.3M | added +4.4% | ≤2013 |
| Raymond James Financial INC | 953.3k | 0.27% | $22.0M | added +5.5% | 2025 Q1 |
| First Trust Advisors LP | 952.0k | 0.27% | $22.0M | added +154.6% | ≤2013 |
| Healthcare OF Ontario Pension Plan Trust Fund | 901.0k | 0.25% | $20.8M | opened | 2026 Q1 |
| Susquehanna International Group | 899.8k | 0.25% | $20.7M | trimmed -34.8% | 2019 Q1 |
| Penserra Capital Management LLC | 815.1k | 0.23% | $18.8M | added +112.9% | 2019 Q2 |
| Allianz Asset Management GmbH | 809.1k | 0.23% | $18.7M | added +68.4% | 2025 Q3 |
| BNP Paribas Financial Markets | 725.1k | 0.20% | $16.7M | added +70.3% | ≤2013 |
| Barclays PLC | 720.8k | 0.20% | $16.6M | added +25.2% | ≤2013 |
| Empyrean Capital Partners, LP | 692.8k | 0.20% | $16.0M | unchanged | 2024 Q3 |
| Prudential Financial INC | 691.2k | 0.19% | $15.9M | added +592.1% | ≤2013 |
| Bank OF America CORP /DE/ | 668.4k | 0.19% | $15.4M | trimmed -0.7% | ≤2013 |
| Hi-Line Capital Management, LLC (focused) | 667.7k | 0.19% | $15.4M | added +20.9% | 2024 Q3 |
| Panagora Asset Management INC | 650.2k | 0.18% | $15.0M | opened | 2026 Q1 |
| Jane Street | 609.5k | 0.17% | $14.1M | added +122.1% | 2014 Q2 |
| Bislett Management, LLC (focused) | 600.0k | 0.17% | $13.8M | unchanged | 2023 Q3 |
| S&co INC | 581.4k | 0.16% | $13.4M | trimmed -17.1% | 2024 Q3 |
| Capital Management CORP /VA | 530.5k | 0.15% | $12.2M | added +3.3% | 2024 Q4 |
| Millennium Management | 509.1k | 0.14% | $11.7M | added +108.8% | ≤2013 |
| PDT Partners | 475.2k | 0.13% | $11.0M | opened | 2026 Q1 |
Largest 50 of 545 shown; the full ranked, searchable register is at boothcheck.com/holders/SIRI. 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.