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, Q2 2025
Institutional positions in White Mountains Insurance Group Ltd as of Jun 30, 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
- 325
- +7 vs. Q1 2025
- Shares held
- 2.32M
- +12.3K (+0.5%) vs. Q1 2025
- Total value
- $4.17B
- −$275.8M (−6.2%) vs. Q1 2025
- New holders
- 33
- 103 more added
- Sold out
- 26
- 112 more reduced
4 institutions that held it in Q1 2025 haven't filed for Q2 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q1 2025: 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, Q2 2025
Shares, value and share of portfolio for each institution holding White Mountains Insurance Group Ltd; share changes are against Q1 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Vanguard Group Inc | 249,170 | $447.4M | 0.01% | −946−0.4% | Reduced |
| Morgan Stanley | 165,064 | $296.4M | 0.02% | −5,567−3.3% | Reduced |
| Dimensional Fund Advisors LP | 155,753 | $279.7M | 0.06% | −864−0.6% | Reduced |
| BlackRock, Inc. | 113,158 | $203.2M | 0.00% | −3,641−3.1% | Reduced |
| River Road Asset Management, LLC | 109,892 | $196.5M | 2.49% | +227+0.2% | Added |
| Fuller & Thaler Asset Management, Inc. | 100,984 | $181.3M | 0.66% | −9,108−8.3% | Reduced |
| Boston Partners | 89,394 | $160.5M | 0.18% | +4,158+4.9% | Added |
| Neuberger Berman Group LLC | 83,699 | $150.3M | 0.12% | +26,835+47.2% | Added |
| Wallace Capital Management Inc. | 79,036 | $141.9M | 19.34% | −895−1.1% | Reduced |
| Cooke & Bieler LP | 76,781 | $137.9M | 1.38% | +22,129+40.5% | Added |
| Fiduciary Management Inc | 71,478 | $128.4M | 1.23% | −317−0.4% | Reduced |
| London Co of Virginia | 68,770 | $123.5M | 0.70% | −388−0.6% | Reduced |
| T. Rowe Price Investment Management, Inc. | 62,941 | $113.0M | 0.07% | +475+0.8% | Added |
| State Street Corp | 57,241 | $102.8M | 0.00% | +2,297+4.2% | Added |
| Geode Capital Management, LLC | 42,529 | $76.4M | 0.01% | +343+0.8% | Added |
| Reinhart Partners, Inc. | 41,694 | $74.9M | 2.56% | −784−1.8% | Reduced |
| Bank of America Corp | 39,409 | $70.8M | 0.01% | −1,646−4.0% | Reduced |
| Lord, Abbett & Co. LLC | 32,227 | $57.9M | 0.19% | −624−1.9% | Reduced |
| Raymond James Financial Inc | 30,677 | $55.1M | 0.02% | −1,047−3.3% | Reduced |
| Norges Bank | 30,494 | $54.8M | 0.01% | −476−1.5% | Reduced |
| Allspring Global Investments Holdings, LLC | 29,585 | $53.0M | 0.09% | +4,728+19.0% | Added |
| Spears Abacus Advisors LLC | 28,347 | $50.9M | 1.03% | −321−1.1% | Reduced |
| Wellington Management Group LLP | 24,651 | $44.3M | 0.01% | −787−3.1% | Reduced |
| Charles Schwab Investment Management Inc | 24,183 | $43.4M | 0.01% | −523−2.1% | Reduced |
| Mraz, Amerine & Associates, Inc. | 21,576 | $38.7M | 6.21% | +548+2.6% | Added |
| Southeastern Asset Management IncSuperinvestorSoutheastern Asset Management (Longleaf) | 21,094 | $37.9M | 1.91% | +2,610+14.1% | Added |
| Brown Advisory Inc | 20,854 | $37.4M | 0.05% | −1,222−5.5% | Reduced |
| Select Equity Group, L.P. | 17,872 | $32.1M | 0.14% | −10,127−36.2% | Reduced |
| Robeco Institutional Asset Management B.V. | 17,822 | $32.0M | 0.05% | −1,332−7.0% | Reduced |
| Victory Capital Management Inc | 17,640 | $31.7M | 0.02% | +1,549+9.6% | Added |
| Envestnet Asset Management Inc | 17,511 | $31.4M | 0.01% | +242+1.4% | Added |
| Northern Trust Corp | 17,405 | $31.3M | 0.00% | −817−4.5% | Reduced |
| Elkhorn Partners Limited Partnership | 14,900 | $26.8M | 19.45% | −50.0% | Reduced |
| WCM Investment Management, LLC | 13,097 | $23.4M | 0.05% | −148−1.1% | Reduced |
| UBS Asset Management Americas Inc | 12,276 | $22.0M | 0.00% | +989+8.8% | Added |
| Speece Thorson Capital Group Inc | 11,383 | $20.4M | 4.16% | +224+2.0% | Added |
| Horizon Kinetics Asset Management LLC | 10,971 | $19.7M | 0.23% | −374−3.3% | Reduced |
| Bank of New York Mellon Corp | 10,860 | $19.5M | 0.00% | −1,710−13.6% | Reduced |
| California Public Employees Retirement System | 10,394 | $18.7M | 0.01% | −1,141−9.9% | Reduced |
| Wells Fargo & Company | 9,587 | $17.2M | 0.00% | +237+2.5% | Added |
| Thompson Siegel & Walmsley LLC | 8,305 | $14.9M | 0.25% | −12−0.1% | Reduced |
| GW&K Investment Management, LLC | 8,272 | $14.9M | 0.13% | −195−2.3% | Reduced |
| AQR Capital Management LLC | 8,084 | $14.4M | 0.01% | −408−4.8% | Reduced |
| Edgestream Partners, L.P. | 7,809 | $14.0M | 0.39% | +4,269+120.6% | Added |
| Perpetual Ltd | 7,727 | $13.9M | 0.16% | 00.0% | Unchanged |
| Goldman Sachs Group Inc | 6,885 | $12.4M | 0.00% | +2,626+61.7% | Added |
| Hotchkis & Wiley Capital Management LLC | 6,869 | $12.3M | 0.04% | −24−0.3% | Reduced |
| Royce & Associates LP | 6,603 | $11.9M | 0.12% | −4,985−43.0% | Reduced |
| American Century Companies Inc | 6,365 | $11.4M | 0.01% | −671−9.5% | Reduced |
| Jane Street Group, LLC | 6,071 | $10.9M | 0.02% | +5,493+950.3% | Added |
| First Trust Advisors LP | 5,672 | $10.2M | 0.01% | −17,255−75.3% | Reduced |
| Bradley Foster & Sargent Inc | 5,522 | $9.92M | 0.16% | +5,522 | New |
| Phocas Financial Corp. | 5,392 | $9.68M | 1.39% | +10.0% | Added |
| Williams Jones Wealth Management, LLC. | 5,193 | $9.33M | 0.11% | 00.0% | Unchanged |
| HRT Financial LP | 5,087 | $9.13M | 0.04% | +5,087 | New |
| UBS Group AG | 5,012 | $9.00M | 0.00% | +1,494+42.5% | Added |
| Swiss National Bank | 4,946 | $8.88M | 0.01% | 00.0% | Unchanged |
| SEI Investments Co | 4,905 | $8.81M | 0.01% | +805+19.6% | Added |
| Legal & General Group Plc | 4,309 | $7.74M | 0.00% | +179+4.3% | Added |
| Quantinno Capital Management LP | 4,290 | $7.70M | 0.03% | −316−6.9% | Reduced |
| Rhumbline Advisers | 4,280 | $7.69M | 0.01% | −192−4.3% | Reduced |
| Prospector Partners LLC | 4,076 | $7.32M | 0.85% | +221+5.7% | Added |
| Invesco Ltd. | 3,646 | $6.55M | 0.00% | −374−9.3% | Reduced |
| Brandywine Global Investment Management, LLC | 3,526 | $6.33M | 0.04% | −100−2.8% | Reduced |
| Ameriprise Financial Inc | 3,482 | $6.25M | 0.00% | −50−1.4% | Reduced |
| Nuveen, LLC | 3,458 | $6.21M | 0.00% | −4,312−55.5% | Reduced |
| Barclays PLC | 3,383 | $6.07M | 0.00% | +88+2.7% | Added |
| Lee Danner & Bass Inc | 3,148 | $5.65M | 0.44% | 00.0% | Unchanged |
| Harbor Capital Advisors, Inc. | 2,976 | $5.34M | 0.22% | −82−2.7% | Reduced |
| Creative Planning | 2,842 | $5.10M | 0.00% | +152+5.7% | Added |
| MML Investors Services, LLC | 2,734 | $4.91M | 0.01% | +160+6.2% | Added |
| State Board of Administration of Florida Retirement System | 2,613 | $4.69M | 0.01% | −379−12.7% | Reduced |
| New York State Common Retirement Fund | 2,519 | $4.52M | 0.01% | −204−7.5% | Reduced |
| D. E. Shaw & Co., Inc. | 2,436 | $4.37M | 0.00% | +78+3.3% | Added |
| California State Teachers Retirement System | 2,372 | $4.26M | 0.00% | 00.0% | Unchanged |
| JPMorgan Chase & Co | 2,323 | $4.17M | 0.00% | +337+17.0% | Added |
| Royal Bank of Canada | 2,190 | $3.93M | 0.00% | +908+70.8% | Added |
| Davenport & Co LLC | 2,173 | $3.90M | 0.02% | 00.0% | Unchanged |
| Forum Financial Management, LP | 2,016 | $3.62M | 0.06% | +353+21.2% | Added |
| LPL Financial LLC | 1,985 | $3.56M | 0.00% | +115+6.1% | Added |
| Cerity Partners LLC | 1,900 | $3.41M | 0.01% | +4+0.2% | Added |
| Parsons Capital Management Inc | 1,892 | $3.40M | 0.21% | +384+25.5% | Added |
| Qube Research & Technologies Ltd | 1,792 | $3.22M | 0.00% | +517+40.5% | Added |
| Price T Rowe Associates Inc | 1,751 | $3.15M | 0.00% | +79+4.7% | Added |
| TD Asset Management Inc | 1,618 | $2.91M | 0.00% | +26+1.6% | Added |
| Colony Group, LLC | 1,596 | $2.87M | 0.01% | +249+18.5% | Added |
| STRS Ohio | 1,575 | $2.83M | 0.01% | +430+37.6% | Added |
| HighTower Advisors, LLC | 1,464 | $2.63M | 0.00% | −2−0.1% | Reduced |
| Millennium Management LLC | 1,392 | $2.50M | 0.00% | +436+45.6% | Added |
| Oppenheimer Asset Management Inc. | 1,363 | $2.45M | 0.03% | +28+2.1% | Added |
| Citigroup Inc | 1,362 | $2.45M | 0.00% | +494+56.9% | Added |
| Stifel Financial Corp | 1,344 | $2.41M | 0.00% | −61−4.3% | Reduced |
| Agf Management Ltd | 1,332 | $2.39M | 0.01% | +56+4.4% | Added |
| Main Street Financial Solutions, LLC | 1,293 | $2.32M | 0.17% | +32+2.5% | Added |
| Truist Financial Corp | 1,240 | $2.23M | 0.00% | −129−9.4% | Reduced |
| Teachers Retirement System of the State of Kentucky | 1,208 | $2.17M | 0.02% | 00.0% | Unchanged |
| Northern Oak Wealth Management Inc | 1,176 | $2.11M | 0.27% | 00.0% | Unchanged |
| Citadel Advisors LLC | 1,171 | $2.10M | 0.00% | −5−0.4% | Reduced |
| Pecaut & Co. | 1,167 | $2.10M | 0.70% | 00.0% | Unchanged |
| Leuthold Group, LLC | 1,165 | $2.09M | 0.25% | −23−1.9% | Reduced |