WHITE MOUNTAINS INSURANCE GROUP LTD

WTMNYSE

$2,019.44-1.48 (-0.07%)as of Oct 5, 2026

Legend

Insider buy

Insider sell

Congress buy

Congress sell

Hedge Funds
bought vs soldGreener markers show more buyers; redder markers show more sellers.

Company share activityNet buybacksNo changeNet dilution

Marker size reflects transaction size.

Insider buy
Insider sell
Congress buy
Congress sell
Hedge Funds bought vs sold

Share activityNet buybacksNo changeNet dilution

Marker size reflects transaction size. Greener fund markers mean more buyers.

Insider Buy
Insider Sell
Congress Buy
Congress Sell
Hedge funds bought vs sold
BuybackNo changeNet dilution

WHITE MOUNTAINS INSURANCE GROUP LTD price and activity chart data

Showing the 1Y range: Oct 6, 2025 to Oct 5, 2026. Price (+8.3%). 0 insider or congressional trades plotted in this window as 0 markers; nearby trades of the same kind are grouped.

Transactions plotted on the price chart
Date	Category	Person	Role	Action	Amount	Change in holding

Largest institutional holders

13F · Q2 2026

Fund	% of company held	Value	% of portfolio	Quarterly activity
Dimensional Fund Advisors LP	6.66%	$330M	0.06%	Not reported
Neuberger Berman Group LLC	4.99%	$247M	0.16%	Not reported
BlackRock, Inc.	4.94%	$244M	0.00%	Not reported
Vanguard Portfolio Management LLC	4.69%	$232M	0.01%	Not reported
Vanguard Capital Management LLC	4.50%	$223M	0.00%	Not reported
Fuller & Thaler Asset Management, Inc.	4.27%	$211M	0.58%	Not reported
Cooke & Bieler LP	3.57%	$176M	2.04%	Reduce 18.82%
Wallace Capital Management Inc.	3.35%	$166M	18.20%	Add 1.61%
Fiduciary Management Inc	2.79%	$138M	1.96%	Not reported
Gendell Jeffrey L	2.48%	$123M	1.08%	Add 56.67%
London Co of Virginia	2.26%	$112M	0.64%	Reduce 5.44%
State Street Corp	2.11%	$104M	0.00%	Not reported
Geode Capital Management, LLC	2.07%	$102M	0.01%	Not reported
Morgan Stanley	1.96%	$97.2M	0.01%	Not reported
Reinhart Partners, LLC.	1.86%	$92.3M	2.11%	Add 19.01%
T. Rowe Price Investment Management, Inc.	1.43%	$71M	0.05%	Reduce 17.53%
Lord, Abbett & Co. LLC	1.38%	$68.1M	0.19%	Reduce 0.85%
American Century Companies Inc	1.30%	$64.5M	0.03%	Not reported
Norges Bank	1.17%	$58M	0.01%	Not reported
Cannell & Spears LLC	1.16%	$57.2M	1.02%	Reduce 1.61%
Bank of America Corp	1.05%	$51.9M	0.00%	Not reported
Charles Schwab Investment Management Inc	0.98%	$48.7M	0.01%	Not reported
Mraz, Amerine & Associates, Inc.	0.93%	$46.1M	6.61%	Add 0.18%
Gotham Asset Management, LLC	0.75%	$37.2M	0.09%	Add 98.30%
Brown Advisory Inc	0.74%	$36.7M	0.06%	Not reported
Jane Street Group, LLC	0.72%	$35.7M	0.00%	Not reported
Southeastern Asset Management Inc	0.72%	$35.5M	1.85%	Reduce 9.33%
UBS Group AG	0.68%	$33.6M	0.00%	Not reported
Vanguard Fiduciary Trust Co	0.64%	$31.8M	0.01%	Not reported
Raymond James Financial Inc	0.62%	$30.8M	0.01%	Not reported
Northern Trust Corp	0.61%	$30.2M	0.00%	Not reported
Wellington Management Group LLP	0.61%	$30.1M	0.01%	Reduce 2.36%
Envestnet Asset Management Inc	0.58%	$28.7M	0.01%	Not reported
Quantinno Capital Management LP	0.53%	$26.2M	0.03%	Add 29.03%
Elkhorn Partners Limited Partnership	0.52%	$25.5M	21.89%	Reduce 2.99%
Horizon Kinetics Asset Management LLC	0.51%	$25.3M	0.29%	Not reported
Goldman Sachs Group Inc	0.51%	$25.2M	0.00%	Not reported
Boussard & Gavaudan Gestion Sas	0.49%	$24.5M	1.23%	Not reported
Victory Capital Management Inc	0.45%	$22.2M	0.01%	Not reported
First Trust Advisors LP	0.44%	$22M	0.01%	Add 246.76%
Qube Research & Technologies Ltd	0.41%	$20.1M	0.02%	Not reported
Speece Thorson Capital Group Inc	0.39%	$19.1M	4.08%	Not reported
Wells Fargo & Company	0.36%	$18.1M	0.00%	Not reported
Bank of New York Mellon Corp	0.35%	$17.4M	0.00%	Not reported
Sei Investments Co	0.34%	$16.8M	0.01%	Not reported
GW&K Investment Management, LLC	0.33%	$16.3M	0.13%	Not reported
Thompson Siegel & Walmsley LLC	0.32%	$15.9M	0.28%	Add 6.20%
Arrowstreet Capital, Limited Partnership	0.31%	$15.1M	0.01%	Not reported
Citadel Advisors LLC	0.30%	$14.8M	0.00%	Not reported
Hotchkis & Wiley Capital Management LLC	0.28%	$14.1M	0.04%	Add 12.24%

50 of 328 holders

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