WHITE MOUNTAINS INSURANCE GROUP LTD
InsuranceCIK
776867
Location
HANOVER, NH
Portfolio Value
Small
$313,368,520
Diversification
Highly concentrated
Filing Date
Global Rank
#3,041
/ 8,232
▲ 499
Top Industry
Internet Content & Information
100.0%
3Y Alpha vs SPY
-18.1%
Period ended 2 months ago
Filed May 12, 2026 · 32d
22 quarters · since Dec 2020
Clone Performance
Jun 2023–Jun 2026 · vs SPYHypothetical growth of cloning every reported 13F position and rebalancing on each filing, indexed to the same start.
Cloned portfolio
+9.3%
SPY
+76.5%
Annualised alpha
-17.9%
Max drawdown
−49.4%
Estimate. 13F holdings are quarter-lagged and long-only, so the clone rebalances about 45 days after each period end — when the filing becomes public — and excludes options and short positions. Past performance does not predict future results.
Portfolio Concentration
2 positions · as of Mar 31, 2026 · Δ vs Dec 31, 2025Top Position
53.0%
−35.3 pts
Top 5
100.0%
0.0 pts
Top 10
100.0%
0.0 pts
HHI
5,018
Highly concentrated−2,913
Portfolio Trend
22 quarters · across all stocks
Sector Breakdown
As of Mar 31, 2026| Sector | % Portfolio | Value |
|---|---|---|
| Communication Services | 53.0% | $166,066,510 |
| Unclassified | 47.0% | $147,302,010 |
Last Quarter's Activity
Export CSVAdded To
Positions the filer increased
1 positions
| Ticker | Company | Δ Shares | Shares | Value | Open |
|---|---|---|---|---|---|
| SPY | Spdr S&P 500 ETF Trust | +181,500 | 226,500 | $147,302,010 | |
| No positions match the current search. | |||||
Trimmed
Positions the filer reducedNo qualifying positions this quarter.
New Positions
Positions the filer opened this quarterNo qualifying positions this quarter.
Sold Out
Positions the filer fully exitedNo qualifying positions this quarter.
2 positions ·
$313,368,520 total
· as of Mar 31, 2026
| Ticker | Company | Type | Shares | Value (USD) | % of Portfolio | History |
|---|---|---|---|---|---|---|
| MAX |
MediaAlpha, Inc.
Communication Services
|
Held | 17,856,614 | $166,066,510 | 52.99% | |
| SPY |
Spdr S&P 500 ETF Trust
|
Added | 226,500 | $147,302,010 | 47.01% |