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, Q4 2025
Institutional positions in White Mountains Insurance Group Ltd as of Dec 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
- 353
- +20 vs. Q3 2025
- Shares held
- 2.25M
- −77.3K (−3.3%) vs. Q3 2025
- Total value
- $4.67B
- +$782.8M (+20.1%) vs. Q3 2025
- New holders
- 55
- 104 more added
- Sold out
- 35
- 126 more reduced
5 institutions that held it in Q3 2025 haven't filed for Q4 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q3 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, Q4 2025
Shares, value and share of portfolio for each institution holding White Mountains Insurance Group Ltd; share changes are against Q3 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| TD Asset Management Inc | 1,000 | $2.08M | 0.00% | −166−14.2% | Reduced |
| Holocene Advisors, LP | 998 | $2.07M | 0.00% | +159+19.0% | Added |
| FMR LLC | 939 | $1.95M | 0.00% | +314+50.2% | Added |
| O'Shaughnessy Asset Management, LLC | 934 | $1.94M | 0.01% | −49−5.0% | Reduced |
| Brave Asset Management Inc | 924 | $1.92M | 0.45% | 00.0% | Unchanged |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 913 | $1.90M | 0.00% | +660+260.9% | Added |
| CI Private Wealth, LLC | 906 | $1.88M | 0.00% | +308+51.5% | Added |
| Sequoia Financial Advisors, LLC | 906 | $1.88M | 0.01% | +88+10.8% | Added |
| American Century Companies Inc | 895 | $1.86M | 0.00% | −1,347−60.1% | Reduced |
| Handelsbanken Fonder AB | 880 | $1.83M | 0.01% | −220−20.0% | Reduced |
| Harbor Capital Advisors, Inc. | 864 | $1.79M | 0.14% | +12+1.4% | Added |
| Millennium Management LLC | 856 | $1.78M | 0.00% | −78−8.4% | Reduced |
| Equitable Trust Co | 840 | $1.75M | 0.08% | +53+6.7% | Added |
| Main Street Financial Solutions, LLC | 835 | $1.74M | 0.13% | −426−33.8% | Reduced |
| Arrowstreet Capital, Limited Partnership | 811 | $1.69M | 0.00% | +811 | New |
| Alliancebernstein L.P. | 807 | $1.68M | 0.00% | −148−15.5% | Reduced |
| Regions Financial Corp | 792 | $1.65M | 0.01% | 00.0% | Unchanged |
| Public Employees Retirement System of Ohio | 776 | $1.61M | 0.01% | −38−4.7% | Reduced |
| Teachers Retirement System of the State of Kentucky | 767 | $1.59M | 0.01% | 00.0% | Unchanged |
| Park Avenue Securities LLC | 761 | $1.58M | 0.01% | +59+8.4% | Added |
| Truist Financial Corp | 736 | $1.53M | 0.00% | −437−37.3% | Reduced |
| Nisa Investment Advisors, LLC | 734 | $1.53M | 0.01% | 00.0% | Unchanged |
| Private Management Group Inc | 726 | $1.51M | 0.04% | +726 | New |
| Arizona State Retirement System | 718 | $1.49M | 0.01% | −44−5.8% | Reduced |
| Mercer Global Advisors Inc | 715 | $1.49M | 0.00% | +568+386.4% | Added |
| Squarepoint Ops LLC | 706 | $1.47M | 0.00% | +528+296.6% | Added |
| Captrust Financial Advisors | 705 | $1.47M | 0.00% | −2−0.3% | Reduced |
| Texas Yale Capital Corp. | 687 | $1.43M | 0.04% | +7+1.0% | Added |
| Ethic Inc. | 672 | $1.40M | 0.02% | −71−9.6% | Reduced |
| Brandes Investment Partners, LP | 665 | $1.38M | 0.01% | +51+8.3% | Added |
| Jump Financial, LLC | 658 | $1.37M | 0.02% | +658 | New |
| Wiley Bros.-Aintree Capital, LLC | 638 | $1.33M | 0.01% | +15+2.4% | Added |
| Robeco Institutional Asset Management B.V. | 623 | $1.29M | 0.00% | −16,616−96.4% | Reduced |
| Nelson, Van Denburg & Campbell Wealth Management Group, LLC | 617 | $1.28M | 0.04% | 00.0% | Unchanged |
| Summit Trail Advisors, LLC | 600 | $1.25M | 0.02% | −228−27.5% | Reduced |
| KLP Kapitalforvaltning AS | 595 | $1.24M | 0.00% | −10−1.7% | Reduced |
| AMG National Trust Bank | 595 | $1.24M | 0.03% | +18+3.1% | Added |
| Farther Finance Advisors, LLC | 570 | $1.18M | 0.01% | +94+19.7% | Added |
| Sendero Wealth Management, LLC | 562 | $1.17M | 0.13% | 00.0% | Unchanged |
| King Luther Capital Management Corp | 560 | $1.16M | 0.00% | 00.0% | Unchanged |
| Jain Global LLC | 559 | $1.16M | 0.01% | +260+87.0% | Added |
| Barclays PLC | 559 | $1.16M | 0.00% | −393−41.3% | Reduced |
| Manufacturers Life Insurance Company, The | 555 | $1.15M | 0.00% | +21+3.9% | Added |
| The PNC Financial Services Group, Inc. | 536 | $1.11M | 0.00% | +98+22.4% | Added |
| B.O.S.S. Retirement Advisors, LLC | 533 | $1.11M | 0.35% | 00.0% | Unchanged |
| Qube Research & Technologies Ltd | 532 | $1.11M | 0.00% | −104−16.4% | Reduced |
| Oak Thistle LLC | 530 | $1.10M | 0.15% | −127−19.3% | Reduced |
| Edgestream Partners, L.P. | 529 | $1.10M | 0.03% | −842−61.4% | Reduced |
| Chicago Partners Investment Group LLC | 523 | $1.08M | 0.03% | +7+1.4% | Added |
| CAPROCK Group, Inc. | 509 | $1.06M | 0.02% | +17+3.5% | Added |
| Prospector Partners LLC | 490 | $1.02M | 2.18% | −3,293−87.0% | Reduced |
| Entropy Technologies, LP | 490 | $1.02M | 0.06% | +490 | New |
| Janney Montgomery Scott LLC | 482 | $1.00M | 0.00% | +20+4.3% | Added |
| Sanctuary Advisors, LLC | 475 | $987.2K | 0.01% | −20−4.0% | Reduced |
| Parker Investment Management, LLC | 475 | $987.1K | 0.14% | −25−5.0% | Reduced |
| Pathstone Holdings, LLC | 455 | $945.5K | 0.00% | +63+16.1% | Added |
| Legacy Advisors, LLC | 450 | $935.1K | 0.10% | 00.0% | Unchanged |
| Resona Asset Management Co.,Ltd. | 443 | $920.6K | 0.00% | −9−2.0% | Reduced |
| Bank of Montreal | 431 | $895.6K | 0.00% | −1−0.2% | Reduced |
| Advisor Group Holdings, Inc. | 410 | $852.0K | 0.00% | −3−0.7% | Reduced |
| Mariner, LLC | 402 | $835.4K | 0.00% | +188+87.9% | Added |
| Franklin Resources Inc | 400 | $831.2K | 0.00% | +4+1.0% | Added |
| Pictet Asset Management Holding SA | 400 | $831.2K | 0.00% | +50+14.3% | Added |
| Russell Investments Group, Ltd. | 397 | $825.5K | 0.00% | +46+13.1% | Added |
| Midwest Professional Planners, LTD. | 388 | $806.3K | 0.19% | −234−37.6% | Reduced |
| Global Retirement Partners, LLC | 388 | $806.3K | 0.01% | +45+13.1% | Added |
| Klingenstein Fields & Co LP | 380 | $789.7K | 0.03% | 00.0% | Unchanged |
| Cetera Investment Advisers | 364 | $756.7K | 0.00% | 00.0% | Unchanged |
| RSM US Wealth Management LLC | 364 | $756.6K | 0.01% | −32−8.1% | Reduced |
| Quadrature Capital Ltd | 360 | $748.1K | 0.01% | +360 | New |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 359 | $746.0K | 0.00% | +67+22.9% | Added |
| Roundview Capital LLC | 358 | $744.1K | 0.05% | −15−4.0% | Reduced |
| Glenmede Trust Co NA | 354 | $735.6K | 0.00% | +354 | New |
| Public Employees Retirement Association of Colorado | 353 | $734.0K | 0.00% | 00.0% | Unchanged |
| American Capital Advisory, LLC | 342 | $710.7K | 0.31% | −15−4.2% | Reduced |
| Bryant Woods Investment Advisors, LLC | 340 | $706.5K | 0.27% | 00.0% | Unchanged |
| Lecap Asset Management Ltd | 340 | $706.5K | 0.28% | +340 | New |
| Lummis Asset Management, LP | 325 | $675.4K | 0.42% | 00.0% | Unchanged |
| Vestmark Advisory Solutions, Inc. | 321 | $667.0K | 0.01% | +164+104.5% | Added |
| Legacy Wealth Asset Management, LLC | 313 | $650.4K | 0.16% | +5+1.6% | Added |
| Rockefeller Capital Management L.P. | 300 | $623.5K | 0.00% | +80+36.4% | Added |
| Brown Miller Wealth Management, LLC | 298 | $620.2K | 0.17% | 00.0% | Unchanged |
| Greenland Capital Management LP | 290 | $602.6K | 0.09% | +290 | New |
| SRS Capital Advisors, Inc. | 281 | $584.8K | 0.02% | −227−44.7% | Reduced |
| Highlander Partners, L.P. | 280 | $581.8K | 0.21% | 00.0% | Unchanged |
| Cresset Asset Management, LLC | 279 | $579.8K | 0.00% | −5−1.8% | Reduced |
| Essex Savings Bank | 275 | $571.5K | 0.12% | −9−3.2% | Reduced |
| Commonwealth Equity Services, LLC | 271 | $563.4K | 0.00% | −29−9.7% | Reduced |
| Envestnet Portfolio Solutions, Inc. | 261 | $542.4K | 0.00% | +7+2.8% | Added |
| JustInvest LLC | 253 | $525.7K | 0.01% | +13+5.4% | Added |
| Voya Investment Management LLC | 243 | $505.0K | 0.00% | +35+16.8% | Added |
| Shotwell Rutter Baer Inc | 242 | $502.0K | 0.30% | −28−10.4% | Reduced |
| Deutsche Bank AG | 237 | $492.5K | 0.00% | +3+1.3% | Added |
| Wedbush Securities Inc | 229 | $476.0K | 0.01% | +5+2.2% | Added |
| Athena Investment Management | 229 | $475.9K | 0.24% | 00.0% | Unchanged |
| XTX Topco Ltd | 229 | $475.9K | 0.01% | +229 | New |
| David Loasby | 230 | $474.0K | 0.03% | +17+8.0% | Added |
| Hengehold Capital Management LLC | 227 | $471.7K | 0.04% | −167−42.4% | Reduced |
| Wealth Enhancement Advisory Services, LLC | 227 | $464.7K | 0.00% | +17+8.1% | Added |
| Mount Yale Investment Advisors, LLC | 223 | $463.4K | 0.02% | +66+42.0% | Added |