Welcome to our dedicated page for White Mountains SEC filings (Ticker: WTM), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
White Mountains Insurance Group Ltd. filings document the formal disclosures of a Bermuda-incorporated insurance and financial-services holding company with common shares listed on the New York Stock Exchange and the Bermuda Stock Exchange. The record includes 8-K reports on operating results, non-GAAP reconciliations, capital deployment, acquisitions, dispositions and reinsurance arrangements.
Filings also cover proxy governance, annual meeting matters, capital structure and shareholder actions, including share repurchase and tender-offer disclosures. Company-specific exhibits and pro forma materials describe transactions involving White Mountains Partners, Ark/WM Outrigger, Kudu, Distinguished and the completed sale of Bamboo, alongside risk and financial disclosures tied to insurance, reinsurance, investment portfolio performance and capital management.
White Mountains Insurance Group furnished its 2026 Annual Investor Presentation, highlighting a very strong 2025 and solid early 2026. Book value per share grew 25% in 2025 to $2,188, supported by the majority sale of Bamboo at a $1.75 billion valuation and continued investment gains.
Total capital was $7.0 billion as of 1Q26, with $0.8 billion of undeployed capital and consolidated debt at 12% of total capital. Key businesses reported robust results, including Ark with $2.6 billion of 2025 gross written premiums at an 83% combined ratio, Kudu with $70 million of Annualized Adjusted EBITDA, BAM premiums of $160 million, and MediaAlpha revenue of $1.1 billion.
Tanner David Allen reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD director David Allen Tanner received an equity grant of 135 common shares as an annual director share award. The shares were awarded at no cash cost per share and increased his direct holdings to 2,014 common shares following the transaction.
SHANK SUZANNE F. reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD director Suzanne F. Shank received an annual director share award of 135 Common Shares on May 21, 2026. The grant was at a stated price of $0.00 per share and increased her direct holdings to 1,006 Common Shares.
Hicks Weston M reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD director Weston M. Hicks received a grant of 190 Common Shares as an annual chairman share award. The shares were awarded at a price of $0.00 per share, indicating they were compensation rather than a market purchase. Following this award, Hicks directly holds 2,936 Common Shares of the company. The filing reflects a routine equity compensation grant to a director, with no open-market buying or selling activity disclosed.
WHITE MOUNTAINS INSURANCE GROUP LTD director Philip A. Gelston received an annual director share award of 135 common shares on May 21, 2026. The shares were granted at a stated price of $0.00 per share as equity compensation, not a market purchase.
Following this award, Gelston directly holds 1,703 common shares. This Form 4 reflects a routine grant/award acquisition rather than an open‑market buy or sale.
Dillon Margaret reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD director Margaret Dillon received an annual share award of 135 Common Shares. The grant was recorded at a price of $0.00 per share as compensation, not a market purchase. Following this award, her direct holdings total 1,080 Common Shares.
Chu John reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD director John Chu received an award of 135 Common Shares as part of an Annual Director Share Award on May 21, 2026. The shares were granted at no cost and are a compensation-related issuance rather than an open-market purchase or sale.
Following this grant, Chu directly holds 335 Common Shares of the company.
WHITE MOUNTAINS INSURANCE GROUP LTD director John Chu has filed an initial ownership report on Form 3. The filing shows that he beneficially owns 200 common shares directly after the reported event. The document does not reflect any recent purchase or sale activity, only his starting stake as an insider.
WHITE MOUNTAINS INSURANCE GROUP LTD director Mary C. Choksi received an Annual Director Share Award of 135 Common Shares on May 21, 2026. The shares were granted at $0.00 per share as equity compensation, not as an open-market purchase.
Following this award, Choksi directly holds 1,993 Common Shares of the company. The filing does not show any sales or option exercises, only this routine grant classified as a “grant, award, or other acquisition.”
WHITE MOUNTAINS INSURANCE GROUP LTD director Peter M. Carlson received an annual director share award in the form of 135 Common Shares on May 21, 2026. The shares were granted at a price of $0.00 per share as compensation, not as an open-market purchase.
Following this award, Carlson directly holds 852 Common Shares of the company. The filing reports no derivative securities and no sales or disposals, only this grant/award acquisition.