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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.
White Mountains Insurance Group Ltd filed a Form 13F reporting institutional holdings. The filing lists 2 holdings with a combined reported market value of $261,929,551. The report is signed by Michaela J. Hildreth, Managing Director and Chief Accounting Officer.
Morgan Stanley has filed an amended Schedule 13G/A reporting its beneficial ownership in White Mountains Insurance Group Ltd. common stock as of 12/31/2025. The firm reports beneficial ownership of 76,817 shares, representing 3.0% of the outstanding common stock.
Morgan Stanley reports 0 shares with sole voting or dispositive power, 53,289 shares with shared voting power, and 76,817 shares with shared dispositive power. It states that it has ceased to be the beneficial owner of more than five percent of this class and that the shares are held in the ordinary course of business, not to influence control of the issuer.
White Mountains Insurance Group reported strong fourth-quarter and full-year 2025 results, driven primarily by the sale of Bamboo and solid insurance and investment performance. Book value per share reached $2,188 as of December 31, 2025, up 18% in the quarter and 25% for the year including dividends.
For 2025, net income attributable to common shareholders was $1.11 billion, helped by an $816 million net gain on the Bamboo transaction. Bamboo was sold to CVC Capital Partners for $848 million in cash, with White Mountains retaining a 15% fully diluted equity interest valued at $250 million.
Ark delivered a full-year combined ratio of 83% on $2.6 billion of gross written premiums, up 16%. Excluding MediaAlpha, the investment portfolio returned 2.0% in the quarter and 8.9% for the year. The company repurchased $203 million of shares in 2025 at about 92% of year-end book value per share, and reported roughly $1.0 billion of undeployed capital including a January distribution from Outrigger Re.
White Mountains Insurance Group Ltd. reported that investment firms Neuberger Berman Group LLC and Neuberger Berman Investment Advisers LLC have filed a Schedule 13G for its common shares as of 12/31/2025.
Neuberger Berman Group LLC may be deemed to beneficially own 129,654 shares, or 5.1% of the class, all through shared voting or investment authority. Neuberger Berman Investment Advisers LLC may be deemed to beneficially own 125,524 shares, or 4.9%. The filing explains that these shares are held in various fiduciary and advisory accounts for unrelated clients, who retain the economic interest in the securities.
The Neuberger entities state that the holdings were acquired and are held in the ordinary course of business and are not intended to change or influence control of White Mountains. No single client has more than 5% of the issuer’s shares.
White Mountains Insurance Group, Ltd. reported that its specialty property and casualty subsidiary, Ark Insurance Holdings Limited, has renewed Outrigger Re Ltd., a reinsurance sidecar, for business incepting during calendar year 2026 on terms similar to 2025. Outrigger has again entered into a quota share with Ark to provide collateralized reinsurance protection on a portion of Ark Bermuda’s global property catastrophe portfolio.
For the 2026 underwriting year, Outrigger deployed $70 million of total investor capital, all provided by third-party investors and excluding White Mountains. The filing notes that Outrigger’s size was reduced compared with the prior year because Ark increased its use of traditional quota share reinsurance for 2026.
White Mountains Insurance Group executive MD & Chief Accounting Officer reported a routine change in holdings. On January 1, 2026, 600 restricted common shares became unrestricted, and 274 common shares were withheld by the company to cover the reporting person's tax obligations. This withholding is shown as a disposition transaction.
After this event, the reporting person beneficially owned 2,491 common shares and 1,225 restricted common shares directly, plus 20 common shares held indirectly through a 401(k) plan.