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 |
|---|---|---|---|---|---|
| Venturi Wealth Management, LLC | 221 | $459.2K | 0.02% | +7+3.3% | Added |
| Principal Securities, Inc. | 216 | $448.9K | 0.01% | +6+2.9% | Added |
| Private Advisor Group, LLC | 213 | $442.6K | 0.00% | +2+0.9% | Added |
| Atria Investments LLC | 209 | $434.4K | 0.00% | +22+11.8% | Added |
| Bryn Mawr Trust Co | 209 | $434.3K | 0.01% | 00.0% | Unchanged |
| Hudson Value Partners, LLC | 206 | $428.2K | 0.13% | 00.0% | Unchanged |
| Toroso Investments, LLC | 204 | $423.9K | 0.00% | −404−66.4% | Reduced |
| We Are One Seven, LLC | 204 | $423.9K | 0.01% | +17+9.1% | Added |
| Cambridge Investment Research Advisors, Inc. | 200 | $416.0K | 0.00% | +200 | New |
| Ensign Peak Advisors, Inc | 200 | $415.6K | 0.00% | −300−60.0% | Reduced |
| Evercore Wealth Management, LLC | 200 | $415.6K | 0.01% | 00.0% | Unchanged |
| Sage Investment Counsel LLC | 200 | $415.6K | 0.46% | 00.0% | Unchanged |
| Folger Nolan Fleming Douglas Capital Management, Inc | 199 | $413.5K | 0.04% | 00.0% | Unchanged |
| GAMMA Investing LLC | 199 | $413.5K | 0.02% | +16+8.7% | Added |
| GWM Advisors LLC | 196 | $407.3K | 0.00% | +26+15.3% | Added |
| Ritholtz Wealth Management | 195 | $405.2K | 0.01% | −13−6.3% | Reduced |
| Riverwater Partners LLC | 190 | $394.8K | 0.15% | 00.0% | Unchanged |
| Bank of Nova Scotia | 189 | $392.7K | 0.00% | −13−6.4% | Reduced |
| Savant Capital, LLC | 180 | $374.0K | 0.00% | −3−1.6% | Reduced |
| Frank, Rimerman Advisors LLC | 178 | $369.9K | 0.02% | +1+0.6% | Added |
| Keybank National Association | 176 | $365.7K | 0.00% | +9+5.4% | Added |
| Kestra Advisory Services, LLC | 171 | $356.2K | 0.00% | +22+14.8% | Added |
| M&T Bank Corp | 166 | $345.0K | 0.00% | +166 | New |
| Two Sigma Securities, LLC | 160 | $332.5K | 0.05% | −34−17.5% | Reduced |
| Zacks Investment Management | 157 | $326.3K | 0.00% | 00.0% | Unchanged |
| Evelyn Partners Asset Management Ltd | 154 | $320.0K | 0.08% | 00.0% | Unchanged |
| Connable Office Inc | 152 | $315.9K | 0.03% | +23+17.8% | Added |
| Moneta Group Investment Advisors LLC | 150 | $311.7K | 0.00% | 00.0% | Unchanged |
| Change Path, LLC | 150 | $311.7K | 0.01% | 00.0% | Unchanged |
| Douglass Winthrop Advisors, LLC | 150 | $311.7K | 0.01% | 00.0% | Unchanged |
| TCG Advisory Services, LLC | 146 | $303.4K | 0.01% | −14−8.8% | Reduced |
| Sterling Capital Management LLC | 146 | $303.4K | 0.00% | −8−5.2% | Reduced |
| Evergreen Capital Management LLC | 143 | $297.2K | 0.01% | −3−2.1% | Reduced |
| Chapman Investment Management, LLC | 143 | $297.2K | 0.22% | 00.0% | Unchanged |
| Syon Capital LLC | 140 | $290.9K | 0.01% | +140 | New |
| State of Wisconsin Investment Board | 138 | $286.8K | 0.00% | −111−44.6% | Reduced |
| Crossmark Global Holdings, Inc. | 137 | $284.7K | 0.00% | +137 | New |
| Utah Retirement Systems | 134 | $278.5K | 0.00% | 00.0% | Unchanged |
| State of Wyoming | 134 | $278.5K | 0.03% | +58+76.3% | Added |
| HRT Financial LP | 133 | $276.0K | 0.00% | −3,454−96.3% | Reduced |
| Susquehanna International Group, LLP | 132 | $274.3K | 0.00% | −7,228−98.2% | Reduced |
| HB Wealth Management, LLC | 130 | $270.1K | 0.00% | +4+3.2% | Added |
| AlphaGrep UK Ltd | 129 | $268.1K | 0.09% | +129 | New |
| Quadrant Capital Group LLC | 128 | $266.0K | 0.01% | −5−3.8% | Reduced |
| Amalgamated Bank | 127 | $264.0K | 0.00% | +2+1.6% | Added |
| Pinnacle Associates Ltd | 127 | $263.9K | 0.00% | 00.0% | Unchanged |
| Columbia Asset Management | 125 | $259.8K | 0.05% | 00.0% | Unchanged |
| CIBC Asset Management Inc | 124 | $257.7K | 0.00% | +124 | New |
| US Bancorp | 124 | $257.7K | 0.00% | +1+0.8% | Added |
| Xponance, Inc. | 123 | $255.6K | 0.00% | +3+2.5% | Added |
| NewEdge Wealth, LLC | 122 | $253.5K | 0.00% | +5+4.3% | Added |
| Merit Financial Group, LLC | 121 | $251.5K | 0.00% | +1+0.8% | Added |
| State of Alaska, Department of Revenue | 119 | $247.0K | 0.00% | +2+1.7% | Added |
| Swiss Life Asset Management Ltd | 117 | $243.1K | 0.00% | +117 | New |
| Johnson Investment Counsel Inc | 115 | $239.0K | 0.00% | +115 | New |
| Equity Investment Corp | 113 | $234.8K | 0.00% | +113 | New |
| Storgate, LLC | 113 | $234.8K | 0.19% | +113 | New |
| Kera Capital Partners, Inc. | 114 | $233.1K | 0.03% | +114 | New |
| Jefferies Financial Group Inc. | 112 | $232.7K | 0.00% | +112 | New |
| One Wealth Advisors, LLC | 111 | $230.7K | 0.03% | −72−39.3% | Reduced |
| Great Lakes Advisors, LLC | 110 | $228.6K | 0.00% | +110 | New |
| Sagespring Wealth Partners, LLC | 105 | $218.3K | 0.00% | −27−20.5% | Reduced |
| Ballentine Partners, LLC | 105 | $218.2K | 0.00% | +105 | New |
| Perigon Wealth Management, LLC | 102 | $212.0K | 0.00% | +102 | New |
| Citadel Investment Advisory, Inc. | 100 | $208.0K | 0.09% | 00.0% | Unchanged |
| Vise Technologies, Inc. | 100 | $207.8K | 0.00% | −90−47.4% | Reduced |
| Eastern Bank | 100 | $207.8K | 0.00% | 00.0% | Unchanged |
| First Manhattan Co | 100 | $207.8K | 0.00% | +100 | New |
| Baldwin Brothers Inc | 100 | $207.8K | 0.01% | +100 | New |
| Clearbridge Investments, LLC | 100 | $207.8K | 0.00% | +100 | New |
| Chicago Trust Co NA | 100 | $207.8K | 0.03% | +100 | New |
| Gladstone Institutional Advisory LLC | 100 | $207.8K | 0.01% | +100 | New |
| Ackerman Asset Management, LLC | 100 | $207.8K | 0.14% | +100 | New |
| Childress Capital Advisors, LLC | 99 | $205.7K | 0.03% | +99 | New |
| Covestor Ltd | 97 | $204.0K | 0.11% | +69+246.4% | Added |
| Callan Family Office, LLC | 97 | $201.6K | 0.00% | +97 | New |
| Eagle Bay Advisors LLC | 91 | $189.1K | 0.14% | +91 | New |
| Ronald Blue Trust, Inc. | 89 | $184.9K | 0.00% | −24−21.2% | Reduced |
| LRI Investments, LLC | 79 | $163.4K | 0.01% | −3−3.7% | Reduced |
| KBC Group NV | 72 | $150.0K | 0.00% | 00.0% | Unchanged |
| SG Americas Securities, LLC | 66 | $137.0K | 0.00% | −125−65.4% | Reduced |
| Smithfield Trust Co | 64 | $132.0K | 0.01% | 00.0% | Unchanged |
| Parkside Financial Bank & Trust | 62 | $128.8K | 0.01% | −6−8.8% | Reduced |
| Colonial Trust Co | 61 | $126.8K | 0.02% | 00.0% | Unchanged |
| Caitong International Asset Management Co., Ltd | 61 | $126.8K | 0.03% | +47+335.7% | Added |
| Quent Capital, LLC | 60 | $124.7K | 0.01% | 00.0% | Unchanged |
| MAI Capital Management | 59 | $122.6K | 0.00% | −3−4.8% | Reduced |
| STRS Ohio | 59 | $122.6K | 0.00% | −1−1.7% | Reduced |
| Signaturefd, LLC | 56 | $116.4K | 0.00% | +3+5.7% | Added |
| Federation des caisses Desjardins du Quebec | 55 | $114.3K | 0.00% | +5+10.0% | Added |
| Anchor Investment Management, LLC | 50 | $103.9K | 0.01% | 00.0% | Unchanged |
| Steward Partners Investment Advisory, LLC | 50 | $103.9K | 0.00% | +3+6.4% | Added |
| Parallel Advisors, LLC | 49 | $101.8K | 0.00% | +4+8.9% | Added |
| Stephenson National Bank & Trust | 49 | $101.8K | 0.03% | +20+69.0% | Added |
| Allworth Financial LP | 43 | $89.4K | 0.00% | +8+22.9% | Added |
| MetLife Investment Management | 41 | $85.2K | 0.00% | −1−2.4% | Reduced |
| Valley National Advisers Inc | 40 | $83.0K | 0.01% | 00.0% | Unchanged |
| Clearstead Advisors, LLC | 37 | $76.9K | 0.00% | +6+19.4% | Added |
| Quantbot Technologies LP | 34 | $70.7K | 0.00% | +34 | New |
| Basecamp Wealth Advisors LLC | 34 | $70.7K | 0.02% | +34 | New |