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 |
|---|---|---|---|---|---|
| Change Path, LLC | 150 | $250.7K | 0.01% | +2+1.4% | Added |
| Sterling Capital Management LLC | 154 | $257.4K | 0.00% | −13−7.8% | Reduced |
| Evelyn Partners Asset Management Ltd | 154 | $257.4K | 0.06% | 00.0% | Unchanged |
| Prudential Financial Inc | 156 | $260.8K | 0.00% | +6+4.0% | Added |
| Zacks Investment Management | 157 | $262.4K | 0.00% | +9+6.1% | Added |
| Mount Yale Investment Advisors, LLC | 157 | $262.4K | 0.02% | +81+106.6% | Added |
| Vestmark Advisory Solutions, Inc. | 157 | $262.4K | 0.01% | +157 | New |
| TCG Advisory Services, LLC | 160 | $267.4K | 0.01% | +160 | New |
| Marex Group plc | 163 | $272.5K | 0.00% | +163 | New |
| Keybank National Association | 167 | $279.1K | 0.00% | +9+5.7% | Added |
| GWM Advisors LLC | 170 | $284.2K | 0.00% | 00.0% | Unchanged |
| Frank, Rimerman Advisors LLC | 177 | $295.9K | 0.02% | 00.0% | Unchanged |
| Squarepoint Ops LLC | 178 | $297.5K | 0.00% | −101−36.2% | Reduced |
| One Wealth Advisors, LLC | 183 | $305.9K | 0.04% | −32−14.9% | Reduced |
| GAMMA Investing LLC | 183 | $305.9K | 0.02% | +1+0.5% | Added |
| Savant Capital, LLC | 183 | $305.9K | 0.00% | −4−2.1% | Reduced |
| Inceptionr LLC | 185 | $309.2K | 0.07% | +185 | New |
| We Are One Seven, LLC | 187 | $312.6K | 0.01% | +12+6.9% | Added |
| Susquehanna Portfolio Strategies, LLC | 187 | $312.6K | 0.00% | +187 | New |
| Atria Investments LLC | 187 | $312.7K | 0.00% | −82−30.5% | Reduced |
| Vise Technologies, Inc. | 190 | $317.6K | 0.01% | −6−3.1% | Reduced |
| Riverwater Partners LLC | 190 | $317.6K | 0.13% | +48+33.8% | Added |
| SG Americas Securities, LLC | 191 | $319.0K | 0.00% | +191 | New |
| Two Sigma Securities, LLC | 194 | $324.3K | 0.05% | +24+14.1% | Added |
| Folger Nolan Fleming Douglas Capital Management, Inc | 199 | $332.6K | 0.03% | 00.0% | Unchanged |
| Neville Rodie & Shaw Inc | 200 | $334.0K | 0.02% | 00.0% | Unchanged |
| SummitTX Capital, L.P. | 200 | $334.3K | 0.01% | −99−33.1% | Reduced |
| Evercore Wealth Management, LLC | 200 | $334.3K | 0.00% | 00.0% | Unchanged |
| Sage Investment Counsel LLC | 200 | $334.3K | 0.37% | 00.0% | Unchanged |
| Bank of Nova Scotia | 202 | $337.6K | 0.00% | +6+3.1% | Added |
| Hudson Value Partners, LLC | 206 | $344.3K | 0.11% | 00.0% | Unchanged |
| Voya Investment Management LLC | 208 | $347.7K | 0.00% | −71−25.4% | Reduced |
| National Wealth Management Group, LLC | 208 | $347.7K | 0.13% | +208 | New |
| Ritholtz Wealth Management | 208 | $347.7K | 0.01% | −6−2.8% | Reduced |
| Bryn Mawr Trust Co | 209 | $349.3K | 0.01% | +69+49.3% | Added |
| Principal Securities, Inc. | 210 | $351.0K | 0.01% | +10+5.0% | Added |
| Private Advisor Group, LLC | 211 | $352.7K | 0.00% | 00.0% | Unchanged |
| Mariner, LLC | 214 | $357.4K | 0.00% | −528−71.2% | Reduced |
| Venturi Wealth Management, LLC | 214 | $357.7K | 0.02% | +1+0.5% | Added |
| Rockefeller Capital Management L.P. | 220 | $367.8K | 0.00% | +220 | New |
| Wedbush Securities Inc | 224 | $374.0K | 0.01% | +13+6.2% | Added |
| Athena Investment Management | 229 | $382.8K | 0.20% | 00.0% | Unchanged |
| Deutsche Bank AG | 234 | $391.1K | 0.00% | +24+11.4% | Added |
| Wealth Enhancement Advisory Services, LLC | 210 | $400.1K | 0.00% | −21−9.1% | Reduced |
| JustInvest LLC | 240 | $401.2K | 0.00% | +7+3.0% | Added |
| David Loasby | 213 | $405.8K | 0.03% | +213 | New |
| State of Wisconsin Investment Board | 249 | $416.2K | 0.00% | +7+2.9% | Added |
| Zurcher Kantonalbank (Zurich Cantonalbank) | 253 | $422.9K | 0.00% | 00.0% | Unchanged |
| Envestnet Portfolio Solutions, Inc. | 254 | $424.6K | 0.00% | −73−22.3% | Reduced |
| Highlander Partners, L.P. | 280 | $468.0K | 0.16% | 00.0% | Unchanged |
| Citadel Advisors LLC | 281 | $469.7K | 0.00% | −890−76.0% | Reduced |
| Essex Savings Bank | 284 | $474.7K | 0.11% | 00.0% | Unchanged |
| Cresset Asset Management, LLC | 284 | $474.7K | 0.00% | +2+0.7% | Added |
| Universal- Beteiligungs- und Servicegesellschaft mbH | 292 | $488.1K | 0.00% | +62+27.0% | Added |
| Balyasny Asset Management LLC | 298 | $498.1K | 0.00% | +298 | New |
| Brown Miller Wealth Management, LLC | 298 | $498.8K | 0.14% | 00.0% | Unchanged |
| Jain Global LLC | 299 | $499.8K | 0.01% | −1−0.3% | Reduced |
| Commonwealth Equity Services, LLC | 300 | $502.0K | 0.00% | −24−7.4% | Reduced |
| Shotwell Rutter Baer Inc | 270 | $512.0K | 0.33% | 00.0% | Unchanged |
| Legacy Wealth Asset Management, LLC | 308 | $514.8K | 0.13% | +2+0.7% | Added |
| Virtu Financial LLC | 309 | $516.0K | 0.03% | +309 | New |
| Farringdon Capital, Ltd. | 310 | $518.2K | 0.13% | +310 | New |
| Lummis Asset Management, LP | 325 | $543.2K | 0.36% | 00.0% | Unchanged |
| Teacher Retirement System of Texas | 337 | $563.3K | 0.00% | −54−13.8% | Reduced |
| Bryant Woods Investment Advisors, LLC | 340 | $568.3K | 0.22% | 00.0% | Unchanged |
| Global Retirement Partners, LLC | 343 | $573.3K | 0.01% | +15+4.6% | Added |
| Pictet Asset Management Holding SA | 350 | $585.0K | 0.00% | 00.0% | Unchanged |
| Russell Investments Group, Ltd. | 351 | $586.7K | 0.00% | +234+200.0% | Added |
| Public Employees Retirement Association of Colorado | 353 | $590.0K | 0.00% | 00.0% | Unchanged |
| American Capital Advisory, LLC | 357 | $596.7K | 0.28% | 00.0% | Unchanged |
| Glenmede Investment Management, LP | 362 | $605.1K | 0.00% | −12−3.2% | Reduced |
| Cetera Investment Advisers | 364 | $608.7K | 0.00% | +103+39.5% | Added |
| Capstone Investment Advisors, LLC | 368 | $615.1K | 0.01% | +368 | New |
| QRG Capital Management, Inc. | 369 | $616.8K | 0.01% | −13−3.4% | Reduced |
| Roundview Capital LLC | 373 | $623.6K | 0.04% | −2−0.5% | Reduced |
| Klingenstein Fields & Co LP | 380 | $635.2K | 0.02% | 00.0% | Unchanged |
| Kathleen S. Wright Associates Inc. | 340 | $646.8K | 0.24% | −40−10.5% | Reduced |
| Pathstone Holdings, LLC | 392 | $655.2K | 0.00% | +8+2.1% | Added |
| Hengehold Capital Management LLC | 394 | $658.6K | 0.06% | −99−20.1% | Reduced |
| 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 |
| ExodusPoint Capital Management, LP | 401 | $670.3K | 0.01% | +45+12.6% | Added |
| Tower Research Capital LLC (TRC) | 420 | $702.0K | 0.02% | +230+121.1% | Added |
| Bank of Montreal | 432 | $722.1K | 0.00% | 00.0% | Unchanged |
| Advisor Group Holdings, Inc. | 413 | $730.9K | 0.00% | +23+5.9% | Added |
| The PNC Financial Services Group, Inc. | 438 | $732.1K | 0.00% | +4+0.9% | Added |
| Legacy Advisors, LLC | 450 | $752.2K | 0.09% | +450 | New |
| Resona Asset Management Co.,Ltd. | 452 | $755.5K | 0.00% | −35−7.2% | Reduced |
| Janney Montgomery Scott LLC | 462 | $772.0K | 0.00% | +16+3.6% | Added |
| Farther Finance Advisors, LLC | 476 | $795.7K | 0.01% | +8+1.7% | Added |
| Sanctuary Advisors, LLC | 495 | $827.5K | 0.00% | +65+15.1% | 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 |
| SRS Capital Advisors, Inc. | 508 | $850.6K | 0.01% | +327+180.7% | Added |
| B.O.S.S. Retirement Advisors, LLC | 533 | $890.9K | 0.21% | 00.0% | Unchanged |
| Manufacturers Life Insurance Company, The | 534 | $892.6K | 0.00% | +10+1.9% | Added |
| CAPROCK Group, Inc. | 492 | $900.4K | 0.02% | +492 | New |
| King Luther Capital Management Corp | 560 | $936.1K | 0.00% | −40−6.7% | Reduced |
| Sendero Wealth Management, LLC | 562 | $939.4K | 0.11% | +143+34.1% | Added |