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, Q3 2025
Institutional positions in White Mountains Insurance Group Ltd as of Sep 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
- 338
- +17 vs. Q2 2025
- Shares held
- 2.33M
- +39.1K (+1.7%) vs. Q2 2025
- Total value
- $3.89B
- −$216.4M (−5.3%) vs. Q2 2025
- New holders
- 44
- 105 more added
- Sold out
- 27
- 103 more reduced
4 institutions that held it in Q2 2025 haven't filed for Q3 2025 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q2 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, Q3 2025
Shares, value and share of portfolio for each institution holding White Mountains Insurance Group Ltd; share changes are against Q2 2025.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Handelsbanken Fonder AB | 1,100 | $1.84M | 0.01% | +500+83.3% | Added |
| Cove Street Capital, LLC | 1,083 | $1.81M | 2.36% | +609+128.5% | Added |
| Autumn Glory Partners, LLC | 1,080 | $1.81M | 0.74% | 00.0% | Unchanged |
| O'Shaughnessy Asset Management, LLC | 983 | $1.64M | 0.01% | +44+4.7% | Added |
| Alliancebernstein L.P. | 955 | $1.60M | 0.00% | −172−15.3% | Reduced |
| Barclays PLC | 952 | $1.59M | 0.00% | −2,431−71.9% | Reduced |
| Millennium Management LLC | 934 | $1.56M | 0.00% | −458−32.9% | Reduced |
| Oddo BHF Asset Management SAS | 930 | $1.55M | 0.06% | −34−3.5% | Reduced |
| Brave Asset Management Inc | 924 | $1.54M | 0.38% | 00.0% | Unchanged |
| Magnetar Financial LLC | 881 | $1.47M | 0.01% | +881 | New |
| Harbor Capital Advisors, Inc. | 852 | $1.42M | 0.11% | −2,124−71.4% | Reduced |
| Holocene Advisors, LP | 839 | $1.40M | 0.00% | +839 | New |
| Summit Trail Advisors, LLC | 828 | $1.38M | 0.02% | +456+122.6% | Added |
| Sequoia Financial Advisors, LLC | 818 | $1.37M | 0.01% | −12−1.4% | Reduced |
| Public Employees Retirement System of Ohio | 814 | $1.36M | 0.00% | +4+0.5% | Added |
| Regency Capital Management Inc. | 811 | $1.36M | 0.64% | +811 | New |
| Regions Financial Corp | 792 | $1.32M | 0.01% | +134+20.4% | Added |
| Equitable Trust Co | 787 | $1.32M | 0.06% | 00.0% | Unchanged |
| Teachers Retirement System of the State of Kentucky | 767 | $1.28M | 0.01% | −441−36.5% | Reduced |
| Aquatic Capital Management LLC | 765 | $1.28M | 0.02% | +765 | New |
| Arizona State Retirement System | 762 | $1.27M | 0.01% | +11+1.5% | Added |
| Ethic Inc. | 743 | $1.24M | 0.02% | −37−4.7% | Reduced |
| Nisa Investment Advisors, LLC | 734 | $1.23M | 0.00% | +3+0.4% | Added |
| Captrust Financial Advisors | 707 | $1.18M | 0.00% | −52−6.9% | Reduced |
| Park Avenue Securities LLC | 702 | $1.17M | 0.01% | +65+10.2% | Added |
| Texas Yale Capital Corp. | 680 | $1.14M | 0.04% | +680 | New |
| Oak Thistle LLC | 657 | $1.10M | 0.17% | +657 | New |
| Qube Research & Technologies Ltd | 636 | $1.06M | 0.00% | −1,156−64.5% | Reduced |
| FMR LLC | 625 | $1.04M | 0.00% | +64+11.4% | Added |
| Wiley Bros.-Aintree Capital, LLC | 623 | $1.04M | 0.01% | −14−2.2% | Reduced |
| Midwest Professional Planners, LTD. | 622 | $1.04M | 0.25% | −6−1.0% | Reduced |
| Nelson, Van Denburg & Campbell Wealth Management Group, LLC | 617 | $1.03M | 0.03% | +617 | New |
| Brandes Investment Partners, LP | 614 | $1.03M | 0.01% | +44+7.7% | Added |
| Toroso Investments, LLC | 608 | $1.02M | 0.00% | +608 | New |
| KLP Kapitalforvaltning AS | 605 | $1.01M | 0.00% | +100+19.8% | Added |
| CI Private Wealth, LLC | 598 | $999.2K | 0.00% | −251−29.6% | Reduced |
| Chicago Partners Investment Group LLC | 516 | $981.1K | 0.03% | +5+1.0% | Added |
| AMG National Trust Bank | 577 | $964.5K | 0.02% | +2+0.3% | Added |
| Sendero Wealth Management, LLC | 562 | $939.4K | 0.11% | +143+34.1% | Added |
| King Luther Capital Management Corp | 560 | $936.1K | 0.00% | −40−6.7% | Reduced |
| CAPROCK Group, Inc. | 492 | $900.4K | 0.02% | +492 | New |
| Manufacturers Life Insurance Company, The | 534 | $892.6K | 0.00% | +10+1.9% | Added |
| B.O.S.S. Retirement Advisors, LLC | 533 | $890.9K | 0.21% | 00.0% | Unchanged |
| SRS Capital Advisors, Inc. | 508 | $850.6K | 0.01% | +327+180.7% | Added |
| Ensign Peak Advisors, Inc | 500 | $835.8K | 0.00% | −400−44.4% | Reduced |
| Parker Investment Management, LLC | 500 | $835.8K | 0.11% | 00.0% | Unchanged |
| Sanctuary Advisors, LLC | 495 | $827.5K | 0.00% | +65+15.1% | Added |
| Farther Finance Advisors, LLC | 476 | $795.7K | 0.01% | +8+1.7% | Added |
| Janney Montgomery Scott LLC | 462 | $772.0K | 0.00% | +16+3.6% | Added |
| Resona Asset Management Co.,Ltd. | 452 | $755.5K | 0.00% | −35−7.2% | Reduced |
| Legacy Advisors, LLC | 450 | $752.2K | 0.09% | +450 | New |
| The PNC Financial Services Group, Inc. | 438 | $732.1K | 0.00% | +4+0.9% | Added |
| Advisor Group Holdings, Inc. | 413 | $730.9K | 0.00% | +23+5.9% | Added |
| Bank of Montreal | 432 | $722.1K | 0.00% | 00.0% | Unchanged |
| Tower Research Capital LLC (TRC) | 420 | $702.0K | 0.02% | +230+121.1% | Added |
| ExodusPoint Capital Management, LP | 401 | $670.3K | 0.01% | +45+12.6% | Added |
| Franklin Resources Inc | 396 | $661.9K | 0.00% | −38−8.8% | Reduced |
| Walleye Capital LLC | 396 | $661.9K | 0.01% | +96+32.0% | Added |
| RSM US Wealth Management LLC | 396 | $661.9K | 0.01% | +223+128.9% | Added |
| Hengehold Capital Management LLC | 394 | $658.6K | 0.06% | −99−20.1% | Reduced |
| Pathstone Holdings, LLC | 392 | $655.2K | 0.00% | +8+2.1% | Added |
| Kathleen S. Wright Associates Inc. | 340 | $646.8K | 0.24% | −40−10.5% | Reduced |
| Klingenstein Fields & Co LP | 380 | $635.2K | 0.02% | 00.0% | Unchanged |
| Roundview Capital LLC | 373 | $623.6K | 0.04% | −2−0.5% | Reduced |
| QRG Capital Management, Inc. | 369 | $616.8K | 0.01% | −13−3.4% | Reduced |
| Capstone Investment Advisors, LLC | 368 | $615.1K | 0.01% | +368 | New |
| Cetera Investment Advisers | 364 | $608.7K | 0.00% | +103+39.5% | Added |
| Glenmede Investment Management, LP | 362 | $605.1K | 0.00% | −12−3.2% | Reduced |
| American Capital Advisory, LLC | 357 | $596.7K | 0.28% | 00.0% | Unchanged |
| Public Employees Retirement Association of Colorado | 353 | $590.0K | 0.00% | 00.0% | Unchanged |
| Russell Investments Group, Ltd. | 351 | $586.7K | 0.00% | +234+200.0% | Added |
| Pictet Asset Management Holding SA | 350 | $585.0K | 0.00% | 00.0% | Unchanged |
| Global Retirement Partners, LLC | 343 | $573.3K | 0.01% | +15+4.6% | Added |
| Bryant Woods Investment Advisors, LLC | 340 | $568.3K | 0.22% | 00.0% | Unchanged |
| Teacher Retirement System of Texas | 337 | $563.3K | 0.00% | −54−13.8% | Reduced |
| Lummis Asset Management, LP | 325 | $543.2K | 0.36% | 00.0% | Unchanged |
| Farringdon Capital, Ltd. | 310 | $518.2K | 0.13% | +310 | New |
| Virtu Financial LLC | 309 | $516.0K | 0.03% | +309 | New |
| Legacy Wealth Asset Management, LLC | 308 | $514.8K | 0.13% | +2+0.7% | Added |
| Shotwell Rutter Baer Inc | 270 | $512.0K | 0.33% | 00.0% | Unchanged |
| Commonwealth Equity Services, LLC | 300 | $502.0K | 0.00% | −24−7.4% | Reduced |
| Jain Global LLC | 299 | $499.8K | 0.01% | −1−0.3% | Reduced |
| Brown Miller Wealth Management, LLC | 298 | $498.8K | 0.14% | 00.0% | Unchanged |
| Balyasny Asset Management LLC | 298 | $498.1K | 0.00% | +298 | New |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 292 | $488.1K | 0.00% | +62+27.0% | Added |
| Cresset Asset Management, LLC | 284 | $474.7K | 0.00% | +2+0.7% | Added |
| Essex Savings Bank | 284 | $474.7K | 0.11% | 00.0% | Unchanged |
| Citadel Advisors LLC | 281 | $469.7K | 0.00% | −890−76.0% | Reduced |
| Highlander Partners, L.P. | 280 | $468.0K | 0.16% | 00.0% | Unchanged |
| Envestnet Portfolio Solutions, Inc. | 254 | $424.6K | 0.00% | −73−22.3% | Reduced |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 253 | $422.9K | 0.00% | 00.0% | Unchanged |
| State of Wisconsin Investment Board | 249 | $416.2K | 0.00% | +7+2.9% | Added |
| David Loasby | 213 | $405.8K | 0.03% | +213 | New |
| JustInvest LLC | 240 | $401.2K | 0.00% | +7+3.0% | Added |
| Wealth Enhancement Advisory Services, LLC | 210 | $400.1K | 0.00% | −21−9.1% | Reduced |
| Deutsche Bank AG | 234 | $391.1K | 0.00% | +24+11.4% | Added |
| Athena Investment Management | 229 | $382.8K | 0.20% | 00.0% | Unchanged |
| Wedbush Securities Inc | 224 | $374.0K | 0.01% | +13+6.2% | Added |
| Rockefeller Capital Management L.P. | 220 | $367.8K | 0.00% | +220 | New |
| Venturi Wealth Management, LLC | 214 | $357.7K | 0.02% | +1+0.5% | Added |