White Mountains Insurance Group (WTM) investor relations material

Executive summary

• Achieved 25% growth in book value per share in 2025, driven by the sale of Bamboo and strong operating results across subsidiaries, with Ark growing premiums 16% and Kudu delivering a 13% ROE.

• Completed major acquisitions, including Distinguished Programs and Enterprise Solutions, and repurchased $200 million in shares at accretive prices.

• CEO succession executed with Liam Caffrey promoted to CEO and Manning Rountree retiring, remaining as Senior Advisor through 2028.

• Engaged with shareholders representing 75% of shares, incorporating feedback into governance, compensation, and ESG practices.

Voting matters and shareholder proposals

• Shareholders to vote on: (1) election of four Class II directors for terms ending 2029, (2) advisory approval of executive compensation, and (3) appointment of PwC as independent auditor for 2026.

• Board recommends voting FOR all proposals.

Board of directors and corporate governance

• Board comprises ten directors (seven independent), with 40% overall diversity (30% gender, 20% racial/ethnic).

• Four new directors added since 2023; average tenure is 4.6 years.

• Board led by independent Chairman; 100% committee independence for Audit and Compensation/Nominating & Governance Committees.

• Annual board and committee self-evaluations and robust share ownership guidelines in place.

• Succession planning and talent development are top priorities, with regular review of CEO and senior management succession.