WHITE MOUNTAINS INSURANCE GROUP LTD insider trading

WTMNYSE

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

“Insiders might sell their shares for any number of reasons, but they buy them for only one: they think the price will rise.” — Peter Lynch

Insider Trading vs Stock Price data

Showing the 1Y range: Oct 6, 2025 to Oct 5, 2026. Price (+8.3%). 0 insider transactions 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

Open market purchase

Open market sell

Marker size reflects transaction size.

Net dollar flow · Buy / Sell balance

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Key players

RLRobert Lawrence SeeligEVP & General Counsel0.8775%of company
GMGeorge Manning RountreeChief Executive Officer0.811%of company
RTReid Tarlton CampbellDirector0.4481%of company
LPLiam P. CaffreyChief Executive Officer0.2226%of company
MHMichaela HildrethMD & Chief Accounting Officer0.1817%of company
WMWeston M. HicksDirector0.123%of company
GEGiles E. HarrisonPresident0.1122%of company
DADavid Allen TannerDirector0.0843%of company
MCMary C. ChoksiDirector0.0835%of company
MAMichael A. PapamichaelChief Financial Officer0.0831%of company

AI Activity Analysis

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Insider activity

Fromto

Company	Insider / role	Action	ΔOwn	Avg price	Amount
WTM	Reid Tarlton CampbellDirector	Open market sell$10.3M	-32.1%	$2,050.00	$10.3M	Dec 19, 2025	Dec 22, 2025
WTM	George Manning RountreeChief Executive Officer	Open market sell$10.3M	-20.5%	$2,050.00	$10.3M	Dec 19, 2025	Dec 22, 2025
WTM	Philip A. GelstonDirector	Open market sell$338K	-9.5%	$2,048.51	$338K	Dec 16, 2025	Dec 16, 2025

End of history · 3 transactions