NYSE: WTM
White Mountains Insurance Group Ltd Stock Ownership - Who owns White Mountains Insurance Group?

Insider buying vs selling

Have White Mountains Insurance Group Ltd insiders been buying or selling?

Buy
Sell
NameRoleDateSharesPriceValue
Michaela HildrethMD Chief Accounting Officer2026-01-01274$2.08k
$569.38kSell
Liam P. CaffreyChief Executive Officer2026-01-01425$2.08k
$883.16kSell
Michael A. PapamichaelChief Financial Officer2026-01-01131$2.08k
$272.22kSell
Robert Lawrence SeeligEVP General Counsel2026-01-01398$2.08k
$827.06kSell
Reid Tarlton CampbellDirector2025-12-195,000$2.05k
$10.25MSell
George Manning RountreeChief Executive Officer2025-12-195,000$2.05k
$10.25MSell
Philip A. GelstonDirector2025-12-16165$2.05k
$338.00kSell

1 of 1

WTM insiders have sold more... subscribe to Premium to read more.
Net Insider Buy/Sell (L12M) Ownership

Be the first to know when WTM insiders and whales buy or sell their stock.

WTM Shareholders

What type of owners hold White Mountains Insurance Group Ltd stock?

Institutional
Insider
Retail
NameHoldSharesValueType
John Joseph Byrne33.08%789,535$1.63BInsider
John Davies Gillespie12.70%303,039$624.65MInsider
Berkshire Hathaway Inc3.74%89,279$184.03MInsider
Raymond Joseph Rene Barrette3.13%74,660$153.90MInsider
David Thomas Foy1.28%30,613$63.10MInsider
Bruce R. Berkowitz1.02%24,374$50.24MInsider
Allan Lewis Waters0.77%18,359$37.84MInsider
Reid Tarlton Campbell0.45%10,807$22.28MInsider
Steven Elliot Fass0.40%9,578$19.74MInsider
Robert Phillips Cochran0.34%8,045$16.58MInsider

1 of 3

WTM vs Property & Casualty Insurance Stocks

TickerInst. %Insider %Net Insider (L12M)Net Insider (L3M)
WTM0.09%59.63%Net Selling
HGTY0.03%23.95%Net SellingNet Selling
SIGI0.09%4.54%Net SellingNet Selling
RLI0.10%6.63%Net BuyingNet Buying
MCY0.05%35.79%Net Selling

White Mountains Insurance Group Stock Ownership FAQ

Who owns White Mountains Insurance Group?

White Mountains Insurance Group (NYSE: WTM) is owned by 0.09% institutional shareholders, 59.63% White Mountains Insurance Group insiders, and 40.28% retail investors. John Joseph Byrne is the largest individual White Mountains Insurance Group shareholder, owning 789,535.00 shares representing 33.08% of the company. John Joseph Byrne's White Mountains Insurance Group shares are currently valued at $1.63B.

If you're new to stock investing, here's how to buy White Mountains Insurance Group stock.
WallStreetZen does not provide financial advice and does not issue recommendations or offers to buy stock or sell any security.

Information is provided 'as-is' and solely for informational purposes and is not advice. WallStreetZen does not bear any responsibility for any losses or damage that may occur as a result of reliance on this data.