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.
The White Mountains Insurance Group, Ltd. (WTM) SEC filings page on Stock Titan provides direct access to the company’s U.S. regulatory disclosures, including Forms 10‑K, 10‑Q and 8‑K. As a Bermuda‑domiciled financial services holding company with common shares listed on the New York Stock Exchange and the Bermuda Stock Exchange, White Mountains files detailed reports describing its property and casualty insurance and reinsurance activities, municipal bond reinsurance operations, capital solutions for asset and wealth management firms, insurance distribution platforms and other investments.
In its annual reports on Form 10‑K and quarterly reports on Form 10‑Q, White Mountains presents consolidated financial statements, segment information for businesses such as Ark/WM Outrigger, HG Global, Kudu, Bamboo, Distinguished and Other Operations, and discussions of book value per share, comprehensive income and risk factors. These filings also describe exposures to catastrophic events, reserve adequacy considerations, investment portfolio performance and the impact of holdings such as MediaAlpha.
Current reports on Form 8‑K capture material events affecting WTM. Recent examples include the renewal of Outrigger Re Ltd., a collateralized reinsurance sidecar providing quota share protection on a portion of Ark Bermuda’s global property catastrophe portfolio; the entry into and closing of transactions to acquire a controlling interest in Distinguished Programs; the sale of a controlling financial interest in the Bamboo Group to affiliates of funds advised by CVC Capital Partners while retaining an indirect equity interest; announcements of quarterly results and non‑GAAP segment metrics; and disclosures regarding executive leadership changes.
On Stock Titan, these filings are updated as they are posted to EDGAR and are accompanied by AI‑powered summaries that highlight key points, such as segment performance, transaction terms, capital deployment, and changes in book value per share. Users can quickly scan 10‑K and 10‑Q reports for segment‑level trends, review 8‑K filings for acquisitions, dispositions, tender offers and governance changes, and examine how White Mountains describes risks related to catastrophes, reinsurance capacity, rating agency actions and regulatory developments. The platform also surfaces insider‑related disclosures contained in periodic and current reports, helping investors understand how management and the board respond to evolving conditions in the insurance and financial services markets.
White Mountains Insurance Group Ltd — Schedule 13G/A amendment from The Vanguard Group. The filing states that, following an internal realignment effective January 12, 2026, certain Vanguard subsidiaries will report beneficial ownership separately. The Vanguard Group reports 0 shares beneficially owned and 0% of the class as of the amendment, reflecting disaggregation of holdings across affiliates.
The filing is signed by Ashley Grim, Head of Global Fund Administration, dated 03/27/2026.
WHITE MOUNTAINS INSURANCE GROUP LTD executive Robert Lawrence Seelig, EVP & General Counsel, made a bona fide gift of 50 Common Shares on 2026-03-19. The gift carried no sale proceeds. After this transfer, he directly holds 17,857 Common Shares and 2,500 restricted Common Shares, plus 4 Common Shares held indirectly by his wife and dependent children and 583 Common Shares held indirectly through the WTM Retirement Plan.
WHITE MOUNTAINS INSURANCE GROUP LTD director David Allen Tanner reported a disposition of shares through a bona fide gift. He transferred 225 common shares at a stated price of $0.00 per share on this Form 4. After the gift, he directly owns 1,879 common shares.
Caffrey Liam P reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD reported that Chief Executive Officer Liam P. Caffrey received a grant of 1,500 restricted common shares on February 25, 2026. The award carries no purchase price and is scheduled to vest on January 1, 2029, functioning as stock-based compensation.
Following this grant, Caffrey directly holds 3,650 common shares in total, which includes both restricted and unrestricted stock, and also has 8 common shares held indirectly through the WTM Retirement Plan. The filing does not show any open‑market buying or selling, only this equity award and updated holdings.
Harrison Giles E reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD President Giles E. Harrison reported an equity grant in the form of 775 restricted common shares on February 25, 2026. The award carried a grant price of $0.00 per share and is scheduled to vest on January 1, 2029.
After this grant, his directly held common shares increased to 2,675. In addition, he indirectly holds 2 common shares through a company retirement plan account, reflecting accumulation in that plan report dated as of February 25, 2026.
Hildreth Michaela reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD executive Michaela Hildreth, MD & Chief Accounting Officer, reported receiving a grant of 600 restricted Common Shares on February 25, 2026, at a price of $0.00 per share. The award will vest on January 1, 2029.
After this grant, she directly held 1,825 restricted Common Shares. As of the same date, she also directly held 2,491 Common Shares and indirectly held 20 Common Shares through a 401(k) account.
Papamichael Michael A reported acquisition or exercise transactions in this Form 4 filing.
WHITE MOUNTAINS INSURANCE GROUP LTD Chief Financial Officer Michael A. Papamichael was granted 500 restricted common shares on February 25, 2026, at a stated price of $0.00 per share. These restricted shares vest on January 1, 2029, and bring his directly held restricted-share balance to 1,200 shares.
As of this transaction date, he also directly held 772 common shares and indirectly held 12 common shares through the White Mountains Retirement Plan, reflecting his broader equity stake in the company.
SEELIG ROBERT LAWRENCE reported acquisition or exercise transactions in this Form 4 filing.
White Mountains Insurance Group Ltd. executive vice president and general counsel Robert Lawrence Seelig reported receiving an award of 775 restricted common shares on February 25, 2026. The award was granted at no cost and is scheduled to vest on January 1, 2029.
After this grant, he directly held 2,500 restricted common shares and 17,907 other common shares, along with small indirect holdings of 4 common shares through his wife and dependent children and 583 common shares through the White Mountains Retirement Plan.
White Mountains Insurance Group, Ltd. is a Bermuda-based holding company that buys, operates and sells businesses in insurance, financial services and related areas. As of December 31, 2025, it operated mainly through four reportable segments: Ark/WM Outrigger, HG Global, Kudu and Distinguished, plus Other Operations.
Ark is a specialty property and casualty insurer and reinsurer writing $2,557.2 million of gross written premiums in 2025 across property, specialty, marine & energy, casualty and accident & health, mainly through Lloyd’s and Bermuda platforms. WM Outrigger Re provides collateralized reinsurance to Ark but will not participate in the 2026 underwriting year, with White Mountains receiving sizeable capital distributions.
HG Global provides first-loss reinsurance on municipal bond insurance written by BAM, supporting an insured portfolio of $20,559.9 million of par value with an overall A weighted-average rating and collateral trusts holding $1,007 million of assets. Kudu has deployed about $1.2 billion into 30 asset and wealth managers, targeting high-yield, noncontrolling revenue and earnings interests.
In 2025 White Mountains added new controlled businesses, acquiring Enterprise Solutions and Distinguished, whose programs generated $568 million of managed premiums for the full year. It also exited control of Bamboo via a sale that produced $848 million of cash proceeds and a retained $250 million indirect equity interest, and continued building a diversified portfolio of equity investments, including MediaAlpha, PassportCard/DavidShield, BroadStreet, Elementum and various insurance-linked and private equity holdings.
White Mountains Insurance Group has completed a $125 million structured capital investment in Bishop Street Underwriters, a RedBird Capital Partners portfolio company focused on property and casualty insurance. The investment is described as a strategic growth partnership intended to support Bishop Street’s expansion.
Bishop Street reported 2025 gross written premium above $650 million with organic growth and a portfolio loss ratio below 50 percent. Leaders from Bishop Street, White Mountains and RedBird highlight plans to accelerate acquisitions, launch new programs and expand Bishop Street’s global footprint in 2026.