Featured 13F manager
White Mountains Insurance Group Ltd
Hanover, NH 4 processed 13Fs on this site · 2025 Q3–2026 Q2
- $394M
- 2 Positions
- 2026 Q2
- +25.9% QoQ
- Top 5 100.0%
White Mountains Insurance Group Ltd files a Form 13F. The latest book is 2026 Q2 at $394M, up 25.9% QoQ, led by Mediaalpha and Spdr S&P 500 ETF Tr.
Portfolio
top 5 100.0% · top 10 100.0%
- MAX - Mediaalpha · CL A 57.0%
- SPY - Spdr S&P 500 ETF Tr 43.0%
AUM over time
Latest book
| MAX - Mediaalpha · CL A | 57.03% | Hold | 17,856,614 | $12.57 | $224M | — | — |
| SPY - Spdr S&P 500 ETF Tr | 42.97% | Hold | 226,500 | $746.77 | $169M | — | — |
Filings history
4 periods · normalized AUM · open a period for holdings
| Period | Holdings | AUM | QoQ | Form | Filed | Filing ID |
|---|---|---|---|---|---|---|
| 2026 Q2 | 2 | $394M | +25.9% | 13F-HR | 8/12/2026 | 000110465926094905 |
| 2026 Q1 | 2 | $313M | +19.5% | 13F-HR | 5/12/2026 | 000110465926059351 |
| 2025 Q4 | 2 | $262M | +29.1% | 13F-HR | 2/12/2026 | 000110465926014432 |
| 2025 Q3 | 1 | $203M | — | 13F-HR | 11/13/2025 | 000110465925110906 |
About
White Mountains Insurance Group Ltd
4 processed 13Fs on this site · 2025 Q3–2026 Q2