WHITE MOUNTAINS INSURANCE GROUP LTD

Hanover, NH · CIK 776867 · 13F filing filed 2026-08-12

No investment adviser registration (Form ADV) found for this filer. It may be a parent company whose subsidiaries are the registered advisers, a bank or insurer, or a manager based outside the US.

Legal entityWHITE MOUNTAINS INSURANCE GROUP, LTD. (BM)

$393.6m reported value +25.6% vs Q1 2026

2positions

100.0%in top 10

0 new 0 added 0 reduced 0 sold out vs Q1 2026

Holdings, Q2 2026

The small lines show how much was held over the last 4 quarters (adjusted for stock splits).

#	Security	Ticker	Shares	Value	% of portfolio	Change	Shares change
1	MEDIAALPHA INC CL A MAX	MAX	17,856,614	$224.5m57.03%	57.03%	Unchanged
2	SPDR S&P 500 ETF TR TR UNIT SPY	SPY	226,500	$169.1m42.97%	42.97%	Unchanged

Stakes above 5%

Companies where this manager has reported owning more than 5% of a class of shares, on Schedule 13D (may seek influence) or 13G (passive): its latest filing for each, from 19 Dec 2024 on.

Company	Ticker	Stake	Change	Schedule	Last filed
MEDIAALPHA INC MAX · 13D · filed 2026-05-01	MAX	33.0%≈ $224.5m	+1.3 pts	13D	2026-05-01