White Mountains Insurance Group Ltd
WTM- Exchange
- NYSE
- Industry
- Fire, Marine & Casualty Insurance
- SEC CIK
- 0000776867
No open-market purchases or sales by White Mountains Insurance Group Ltd insiders were filed in the last 90 days; 356 institutions reported holding it in 13F filings for Q2 2026, worth $4.57B in total; Southeastern Asset Management (Longleaf) is the only superinvestor holding it.
13F holders, Q1 2025
Institutional positions in White Mountains Insurance Group Ltd as of Mar 31, 2025. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 322
- 0 vs. Q4 2024
- Shares held
- 2.31M
- +39.7K (+1.7%) vs. Q4 2024
- Total value
- $4.44B
- +$28.3M (+0.6%) vs. Q4 2024
- New holders
- 27
- 102 more added
- Sold out
- 27
- 107 more reduced
3 institutions that held it in Q4 2024 haven't filed for Q1 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2024: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting WTM on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 356 | $4.57B |
| Q1 2026 | 368 | $4.86B |
| Q4 2025 | 353 | $4.67B |
| Q3 2025 | 338 | $3.89B |
| Q2 2025 | 325 | $4.17B |
| Q1 2025 | 322 | $4.44B |
| Q4 2024 | 325 | $4.43B |
| Q3 2024 | 304 | $3.78B |
| Q2 2024 | 306 | $4.14B |
| Q1 2024 | 303 | $4.06B |
| Q4 2023 | 295 | $3.42B |
| Q3 2023 | 272 | $3.40B |
| Q2 2023 | 258 | $3.13B |
| Q1 2023 | 262 | $3.09B |
| Q4 2022 | 265 | $3.20B |
| Q3 2022 | 251 | $2.98B |
| Q2 2022 | 259 | $3.32B |
| Q1 2022 | 244 | $3.09B |
| Q4 2021 | 243 | $2.71B |
| Q3 2021 | 232 | $2.86B |
| Q2 2021 | 233 | $3.11B |
| Q1 2021 | 245 | $3.02B |
Institutions, Q1 2025
Shares, value and share of portfolio for each institution holding White Mountains Insurance Group Ltd; share changes are against Q4 2024.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Mariner, LLC | 720 | $1.39M | 0.00% | −105−12.7% | Reduced |
| Nisa Investment Advisors, LLC | 730 | $1.41M | 0.01% | −370−33.6% | Reduced |
| Arizona State Retirement System | 737 | $1.42M | 0.01% | −9−1.2% | Reduced |
| Sanctuary Advisors, LLC | 756 | $1.46M | 0.01% | −93−11.0% | Reduced |
| Nebula Research & Development LLC | 762 | $1.47M | 0.14% | +762 | New |
| Public Employees Retirement System of Ohio | 794 | $1.53M | 0.01% | −96−10.8% | Reduced |
| Schonfeld Strategic Advisors LLC | 800 | $1.54M | 0.01% | +100+14.3% | Added |
| Mitsubishi UFJ Trust & Banking Corp | 808 | $1.56M | 0.00% | −408−33.6% | Reduced |
| Sequoia Financial Advisors, LLC | 826 | $1.59M | 0.01% | −91−9.9% | Reduced |
| Citigroup Inc | 868 | $1.67M | 0.00% | +108+14.2% | Added |
| Susquehanna International Group, LLP | 873 | $1.68M | 0.00% | +382+77.8% | Added |
| Police & Firemen's Retirement System of New Jersey | 884 | $1.70M | 0.02% | −24−2.6% | Reduced |
| Captrust Financial Advisors | 889 | $1.71M | 0.00% | +292+48.9% | Added |
| Brave Asset Management Inc | 924 | $1.78M | 0.56% | 00.0% | Unchanged |
| Millennium Management LLC | 956 | $1.84M | 0.00% | −1,445−60.2% | Reduced |
| Oddo BHF Asset Management SAS | 990 | $1.91M | 0.08% | −9−0.9% | Reduced |
| Ensign Peak Advisors, Inc | 1,000 | $1.93M | 0.00% | 00.0% | Unchanged |
| Verition Fund Management LLC | 1,014 | $1.95M | 0.01% | +359+54.8% | Added |
| O'Shaughnessy Asset Management, LLC | 1,057 | $2.04M | 0.02% | −8−0.8% | Reduced |
| State of New Jersey Common Pension Fund D | 1,073 | $2.07M | 0.01% | −45−4.0% | Reduced |
| Autumn Glory Partners, LLC | 1,080 | $2.08M | 1.05% | 00.0% | Unchanged |
| Janus Henderson Group PLC | 1,123 | $2.14M | 0.00% | −1,293−53.5% | Reduced |
| First Manhattan Co | 1,115 | $2.15M | 0.01% | 00.0% | Unchanged |
| Treasurer of the State of North Carolina | 1,126 | $2.17M | 0.01% | +30+2.7% | Added |
| STRS Ohio | 1,145 | $2.21M | 0.01% | −356−23.7% | Reduced |
| Alliancebernstein L.P. | 1,155 | $2.22M | 0.00% | −15−1.3% | Reduced |
| Pecaut & Co. | 1,167 | $2.25M | 0.76% | 00.0% | Unchanged |
| Citadel Advisors LLC | 1,176 | $2.26M | 0.00% | +1,176 | New |
| Northern Oak Wealth Management Inc | 1,176 | $2.27M | 0.29% | 00.0% | Unchanged |
| Leuthold Group, LLC | 1,188 | $2.29M | 0.30% | −84−6.6% | Reduced |
| Teachers Retirement System of the State of Kentucky | 1,208 | $2.33M | 0.02% | +128+11.9% | Added |
| Main Street Financial Solutions, LLC | 1,261 | $2.43M | 0.21% | +252+25.0% | Added |
| Qube Research & Technologies Ltd | 1,275 | $2.46M | 0.00% | +207+19.4% | Added |
| Agf Management Ltd | 1,276 | $2.46M | 0.01% | −42−3.2% | Reduced |
| Royal Bank of Canada | 1,282 | $2.47M | 0.00% | −86−6.3% | Reduced |
| Oppenheimer Asset Management Inc. | 1,335 | $2.57M | 0.03% | −212−13.7% | Reduced |
| Colony Group, LLC | 1,347 | $2.59M | 0.01% | −41−3.0% | Reduced |
| Truist Financial Corp | 1,369 | $2.64M | 0.00% | +17+1.3% | Added |
| Stifel Financial Corp | 1,405 | $2.71M | 0.00% | −106−7.0% | Reduced |
| HighTower Advisors, LLC | 1,466 | $2.82M | 0.00% | −97−6.2% | Reduced |
| Dark Forest Capital Management LP | 1,491 | $2.87M | 0.13% | +772+107.4% | Added |
| Parsons Capital Management Inc | 1,508 | $2.90M | 0.16% | −15−1.0% | Reduced |
| TD Asset Management Inc | 1,592 | $3.07M | 0.00% | +212+15.4% | Added |
| Forum Financial Management, LP | 1,663 | $3.20M | 0.05% | +289+21.0% | Added |
| Price T Rowe Associates Inc | 1,672 | $3.22M | 0.00% | +106+6.8% | Added |
| LPL Financial LLC | 1,870 | $3.60M | 0.00% | +107+6.1% | Added |
| Cerity Partners LLC | 1,896 | $3.65M | 0.01% | +48+2.6% | Added |
| JPMorgan Chase & Co | 1,986 | $3.82M | 0.00% | −791−28.5% | Reduced |
| Davenport & Co LLC | 2,173 | $4.18M | 0.02% | −25−1.1% | Reduced |
| D. E. Shaw & Co., Inc. | 2,358 | $4.54M | 0.01% | −361−13.3% | Reduced |
| California State Teachers Retirement System | 2,372 | $4.57M | 0.01% | −26−1.1% | Reduced |
| MML Investors Services, LLC | 2,574 | $4.96M | 0.02% | +232+9.9% | Added |
| Creative Planning | 2,690 | $5.18M | 0.00% | +427+18.9% | Added |
| New York State Common Retirement Fund | 2,723 | $5.24M | 0.01% | 00.0% | Unchanged |
| State Board of Administration of Florida Retirement System | 2,992 | $5.76M | 0.01% | +620+26.1% | Added |
| Harbor Capital Advisors, Inc. | 3,058 | $5.89M | 0.27% | +627+25.8% | Added |
| Lee Danner & Bass Inc | 3,148 | $6.06M | 0.49% | −132−4.0% | Reduced |
| Barclays PLC | 3,295 | $6.35M | 0.00% | +1,153+53.8% | Added |
| UBS Group AG | 3,518 | $6.77M | 0.00% | −788−18.3% | Reduced |
| Ameriprise Financial Inc | 3,532 | $6.80M | 0.00% | +255+7.8% | Added |
| Edgestream Partners, L.P. | 3,540 | $6.82M | 0.23% | +3,540 | New |
| Brandywine Global Investment Management, LLC | 3,626 | $6.98M | 0.05% | −293−7.5% | Reduced |
| Prospector Partners LLC | 3,855 | $7.42M | 0.85% | 00.0% | Unchanged |
| Invesco Ltd. | 4,020 | $7.74M | 0.00% | −329−7.6% | Reduced |
| SEI Investments Co | 4,100 | $7.90M | 0.01% | +883+27.4% | Added |
| Legal & General Group Plc | 4,130 | $7.95M | 0.00% | +81+2.0% | Added |
| Goldman Sachs Group Inc | 4,259 | $8.20M | 0.00% | +1,504+54.6% | Added |
| Rhumbline Advisers | 4,472 | $8.61M | 0.01% | −77−1.7% | Reduced |
| Quantinno Capital Management LP | 4,606 | $8.87M | 0.06% | +2,562+125.3% | Added |
| Swiss National Bank | 4,946 | $9.53M | 0.01% | −100−2.0% | Reduced |
| Williams Jones Wealth Management, LLC. | 5,193 | $10.0M | 0.13% | 00.0% | Unchanged |
| Phocas Financial Corp. | 5,391 | $10.4M | 1.59% | −311−5.5% | Reduced |
| Alaska Permanent Fund Corp | 5,902 | $10.4M | 0.15% | 00.0% | Unchanged |
| Hotchkis & Wiley Capital Management LLC | 6,893 | $13.3M | 0.04% | −473−6.4% | Reduced |
| American Century Companies Inc | 7,036 | $13.6M | 0.01% | +1,661+30.9% | Added |
| Perpetual Ltd | 7,727 | $14.9M | 0.18% | −1,900−19.7% | Reduced |
| Nuveen, LLC | 7,770 | $15.0M | 0.00% | +7,770 | New |
| Thompson Siegel & Walmsley LLC | 8,317 | $16.0M | 0.27% | −1,929−18.8% | Reduced |
| AQR Capital Management LLC | 8,492 | $16.2M | 0.02% | −1,648−16.3% | Reduced |
| GW&K Investment Management, LLC | 8,467 | $16.3M | 0.15% | +56+0.7% | Added |
| Wells Fargo & Company | 9,350 | $18.0M | 0.00% | −196−2.1% | Reduced |
| Speece Thorson Capital Group Inc | 11,159 | $21.5M | 4.43% | −181−1.6% | Reduced |
| UBS Asset Management Americas Inc | 11,287 | $21.7M | 0.01% | +1,183+11.7% | Added |
| Horizon Kinetics Asset Management LLC | 11,345 | $21.8M | 0.25% | +1,256+12.4% | Added |
| California Public Employees Retirement System | 11,535 | $22.2M | 0.02% | −906−7.3% | Reduced |
| Royce & Associates LP | 11,588 | $22.3M | 0.24% | −718−5.8% | Reduced |
| Bank of New York Mellon Corp | 12,570 | $24.2M | 0.00% | −30−0.2% | Reduced |
| WCM Investment Management, LLC | 13,245 | $25.2M | 0.06% | +1,594+13.7% | Added |
| Elkhorn Partners Limited Partnership | 14,905 | $28.7M | 18.81% | −175−1.2% | Reduced |
| Victory Capital Management Inc | 16,091 | $31.0M | 0.03% | +4,543+39.3% | Added |
| Envestnet Asset Management Inc | 17,269 | $33.3M | 0.01% | +855+5.2% | Added |
| Northern Trust Corp | 18,222 | $35.1M | 0.01% | +151+0.8% | Added |
| Southeastern Asset Management IncSuperinvestorSoutheastern Asset Management (Longleaf) | 18,484 | $35.6M | 1.90% | −760−3.9% | Reduced |
| Robeco Institutional Asset Management B.V. | 19,154 | $36.9M | 0.07% | −263−1.4% | Reduced |
| Mraz, Amerine & Associates, Inc. | 21,028 | $40.0M | 6.87% | −41−0.2% | Reduced |
| Brown Advisory Inc | 22,076 | $42.5M | 0.06% | −345−1.5% | Reduced |
| First Trust Advisors LP | 22,927 | $44.2M | 0.04% | +2,709+13.4% | Added |
| Allspring Global Investments Holdings, LLC | 24,857 | $47.3M | 0.08% | +1,621+7.0% | Added |
| Charles Schwab Investment Management Inc | 24,706 | $47.6M | 0.01% | −657−2.6% | Reduced |
| Wellington Management Group LLP | 25,438 | $49.0M | 0.01% | −24,488−49.0% | Reduced |