WTMWhite Mountains Insurance Group, Ltd.

$2,132.11

Who owns WTM

358 institutions reported holding WTM for 2026Q1, together 90% of the company, more than the 348 a quarter earlier.

358

Institutions reporting a position · as of 2026Q1 · up from 348 the quarter before

Shares held by institutions
2.2M

Shares held by institutions · 90% of the company · long US equity positions only, as reported on Form 13F

Reported value
$4.84B

Reported value · at 2026-03-31 prices, not today's

Top 5 holders
31%

Top 5 holders · of the whole company, between five filers

Details
Reporting quarter2026-03-31
2026Q1
Quarters on record
52
New positions
43
Positions exited
38
Added to
113
Reduced
98
Top 10 holdersof the company
49%
Institutional ownership by quarter, 2013Q2 to 2026Q1
QuarterFilersSharesReported value
2026Q13582.2M$4.84B
2025Q43482.2M$4.67B
2025Q33352.3M$3.86B
2025Q23212.3M$4.12B
2025Q13172.3M$4.35B
2024Q43202.2M$4.34B
2024Q33002.2M$3.73B
2024Q23022.3M$4.09B
2024Q12972.4M$3.99B
2023Q42912.2M$3.37B
2023Q32652.2M$3.34B
2023Q22532.2M$3.07B
2023Q12582.2M$3.05B
2022Q42612.2M$3.16B
2022Q32462.3M$2.96B
2022Q22542.6M$3.30B
Largest reported holders, 2026Q1
HolderShares% of companyValue
VANGUARD GROUP INC0.2M10.0%$536M
DIMENSIONAL FUND ADVISORS LP0.2M6.4%$344M
Neuberger Berman Group LLC0.1M5.1%$274M
River Road Asset Management, LLC0.1M4.9%$265M
BlackRock Inc.0.1M4.6%$249M
COOKE & BIELER LP0.1M4.3%$230M
FULLER & THALER ASSET MANAGEMENT, INC.0.1M4.3%$230M
FIDUCIARY MANAGEMENT INC /WI/0.1M3.5%$187M
Wallace Capital Management Inc.0.1M3.2%$173M
MORGAN STANLEY0.1M2.4%$130M

SEC Form 13F data sets (DERA bulk files). 13F is quarterly, filed up to 45 days late, and covers long US equity positions only, no shorts, no derivatives, nothing held below the reporting threshold.

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