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.
Q2 2026 vs. Q1 2026
How the institutions holding White Mountains Insurance Group Ltd changed between Q1 2026 and Q2 2026.
All holders in Q2 2026All holders in Q1 2026
| Measure | Q1 2026 | Of which not filed for Q2 2026 | Q2 2026 | Change |
|---|---|---|---|---|
| Holders | 368 | 5 | 356 | −7 |
| Shares | 2.21M | 15.6K | 2.20M | +8.83K (+0.4%) |
| Value | $4.86B | $34.6M | $4.57B | −$252.8M (−5.2%) |
5 institutions that held it in Q1 2026 haven't filed for Q2 2026 yet. Not filing isn't selling, so the changes leave them out.
New holders (39)
Institutions that held White Mountains Insurance Group Ltd at the end of Q2 2026 but not at the end of Q1 2026.
Sold out (46)
Institutions that held White Mountains Insurance Group Ltd at the end of Q1 2026 and filed for Q2 2026 without it.
Not filed for Q2 2026 yet (5)
Institutions that held White Mountains Insurance Group Ltd at the end of Q1 2026 and haven't filed a 13F for Q2 2026. Not filing isn't selling, so they aren't counted as sold out.
| Institution | Shares, Q1 2026 | Value, Q1 2026 |
|---|---|---|
| Boussard & Gavaudan Investment Management LLP | 13,975 | $31.0M |
| Janus Henderson Group PLC | 1,123 | $2.46M |
| Skopos Labs, Inc. | 295 | $645.9K |
| Evelyn Partners Asset Management Ltd | 154 | $338.3K |
| CWM, LLC | 92 | $202.1K |