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, Q1 2024
Institutional positions in White Mountains Insurance Group Ltd as of Mar 31, 2024. 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
- 303
- +11 vs. Q4 2023
- Shares held
- 2.40M
- +156.9K (+7.0%) vs. Q4 2023
- Total value
- $4.06B
- +$685.0M (+20.3%) vs. Q4 2023
- New holders
- 39
- 91 more added
- Sold out
- 28
- 95 more reduced
3 institutions that held it in Q4 2023 haven't filed for Q1 2024 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2023: 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, Q1 2024
Shares, value and share of portfolio for each institution holding White Mountains Insurance Group Ltd; share changes are against Q4 2023.
| Institution | Shares | Value | % of portfolio | Change in shares | Action |
|---|---|---|---|---|---|
| Dimensional Fund Advisors LP | 161,918 | $290.5M | 0.08% | −390.0% | Reduced |
| Morgan Stanley | 185,530 | $332.9M | 0.03% | −12,471−6.3% | Reduced |
| Vanguard Group Inc | 251,930 | $452.0M | 0.01% | −1,489−0.6% | Reduced |
| Phocas Financial Corp. | 0 | $0 | 0.00% | −5,113−100.0% | Sold out |
| Edgestream Partners, L.P. | 0 | $0 | 0.00% | −1,810−100.0% | Sold out |
| Federated Hermes, Inc. | 0 | $0 | 0.00% | −1,200−100.0% | Sold out |
| Holocene Advisors, LP | 0 | $0 | 0.00% | −424−100.0% | Sold out |
| AE Wealth Management LLC | 0 | $0 | 0.00% | −383−100.0% | Sold out |
| Citadel Advisors LLC | 0 | $0 | 0.00% | −331−100.0% | Sold out |
| Lummis Asset Management, LP | 0 | $0 | 0.00% | −325−100.0% | Sold out |
| Capula Management Ltd | 0 | $0 | 0.00% | −323−100.0% | Sold out |
| HRT Financial LP | 0 | $0 | 0.00% | −260−100.0% | Sold out |
| Soltis Investment Advisors LLC | 0 | $0 | 0.00% | −256−100.0% | Sold out |
| XTX Topco Ltd | 0 | $0 | 0.00% | −252−100.0% | Sold out |
| Two Sigma Securities, LLC | 0 | $0 | 0.00% | −170−100.0% | Sold out |
| Contravisory Investment Management, Inc. | 0 | $0 | 0.00% | −167−100.0% | Sold out |
| Cetera Advisor Networks LLC | 0 | $0 | 0.00% | −161−100.0% | Sold out |
| GTS Securities LLC | 0 | $0 | 0.00% | −155−100.0% | Sold out |
| Sharp Financial Services, LLC | 0 | $0 | 0.00% | −150−100.0% | Sold out |
| Engineers Gate Manager LP | 0 | $0 | 0.00% | −139−100.0% | Sold out |
| KCM Investment Advisors LLC | 0 | $0 | 0.00% | −138−100.0% | Sold out |
| Squarepoint Ops LLC | 0 | $0 | 0.00% | −138−100.0% | Sold out |
| Johnson Financial Group, Inc. | 0 | $0 | 0.00% | −40−100.0% | Sold out |
| Gladius Capital Management LP | 0 | $0 | 0.00% | −19−100.0% | Sold out |
| Spire Wealth Management | 0 | $0 | 0.00% | −13−100.0% | Sold out |
| Loomis Sayles & Co L P | 0 | $0 | 0.00% | −10−100.0% | Sold out |
| Advisory Services Network, LLC | 0 | $0 | 0.00% | −8−100.0% | Sold out |
| O'Dell Group, LLC | 0 | $0 | 0.00% | −7−100.0% | Sold out |
| EdgeRock Capital LLC | 0 | $0 | 0.00% | −6−100.0% | Sold out |
| Global Wealth Management Investment Advisory, Inc. | 0 | $0 | 0.00% | −4−100.0% | Sold out |
| Arlington Trust Co LLC | 0 | $0 | 0.00% | −1−100.0% | Sold out |
| Cannell Peter B & Co Inc | – | – | – | – | Not filed |
| Lee Danner & Bass Inc | – | – | – | – | Not filed |
| Bartlett & Co. LLC | – | – | – | – | Not filed |