Exhibit 99.1 CONTACT: Rob Seelig (603) 640-2212 WHITE MOUNTAINS REPORTS FOURTH QUARTER RESULTS HAMILTON, Bermuda (February 6, 2026) - White Mountains Insurance Group, Ltd. (NYSE: WTM) reported book value per share of $2,188 as of December 31, 2025, an increase of 18% for the fourth quarter of 2025 and 25% for the year ended December 31, 2025, including dividends. Liam Caffrey, CEO, commented, "We had an excellent year, with BVPS growth of 18% in the quarter and 25% for the year. The largest contributor in b ...

HAMILTON, Bermuda, Dec. 24, 2025 /PRNewswire/ -- White Mountains Insurance Group, Ltd. (NYSE: WTM) announced today the final results of its "modified Dutch auction" tender offer. The tender offer expired at 12:00 midnight, New York City time, at the end of the day on December 19, 2025. Based on the final count by the depositary for the tender offer, 64,064 shares were properly tendered and not properly withdrawn at or below the final purchase price of $2,050.00 per share. The Company is purchasing all vali ...

Core Viewpoint - White Mountains Insurance Group, Ltd. announced the preliminary results of its modified Dutch auction tender offer to purchase up to $300 million in common shares, which expired on December 19, 2025 [1] Group 1: Tender Offer Details - A total of 67,186 shares were properly tendered at or below the purchase price of $2,050 per share, including 16,589 shares tendered by notice of guaranteed delivery [2] - The company expects to purchase all validly tendered shares for approximately $137.7 million, representing about 2.6% of White Mountains's shares outstanding as of November 19, 2025 [2] - The final number of shares to be purchased and the final purchase price will be announced after the completion of the confirmation process by the depositary [3] Group 2: Outstanding Shares and Contact Information - Following the payment for the accepted shares, the company expects to have approximately 2,476,555 common shares outstanding [4] - Shareholders seeking additional information about the tender offer can contact D.F. King & Co. or the dealer managers BofA Securities, Inc. and Barclays Capital Inc. [4]

Core Viewpoint - White Mountains Insurance Group, Ltd. has completed the sale of a controlling interest in Bamboo to affiliates of funds advised by CVC Capital Partners [1] Group 1 - The transaction marks a significant strategic move for White Mountains Insurance Group [1] - The sale involves a controlling interest, indicating a major shift in ownership and potential operational direction for Bamboo [1]

Longleaf Partners, managed by Southeastern Asset Management, released its “Small-Cap Fund” third-quarter 2025 investor letter. A copy of the letter can be downloaded here. The fund returned 2.03% in the third quarter, compared with the Russell 3000’s 8.18% and the Russell 2000’s 12.39%. For more information on the fund’s best picks in 2025, please check its top five holdings. In its third-quarter 2025 investor letter, Longleaf Partners Small-Cap Fund highlighted stocks such as White Mountains Insurance Gr ...

Core Insights - The article discusses the growing momentum around the issue of banning Congressional stock trading, highlighting that both retail investors and members of Congress are questioning the practice [1][2]. Stock Analysis - **LCI Industries (NYSE: LCII)**: This company, which manufactures components for the RV, marine, and housing industries, saw a significant stock increase of 24.2% following a trade by Congressman Tony Wied, who reported a purchase between $1 million and $5 million at an average price of $92.02. The RV industry is projected to see sales of approximately 337,000 units by the end of 2025, indicating potential growth [5][6][7]. - **LGI Homes (NASDAQ: LGIH)**: Focused on first-time homebuyers, LGI Homes' stock rose over 28% after Congressman Tim Moore purchased between $15,000 and $50,000 at an average price of $40.83. Analysts have set a consensus price target of $72.13, suggesting a potential gain of over 36% from its closing price on November 28. This aligns with signs of recovery in the housing market, although growth is limited to specific regions [8][10][11]. - **White Mountains Insurance Group (NYSE: WTM)**: This diversified insurance holding company saw its stock increase by 10.6% after Congressman Michael McCaul made two purchases between $15,000 and $50,000. The stock's performance is supported by strong earnings and a buyback plan, with the company initiating a self-tender offer to purchase up to $300 million in common shares [12][13][14].

Accessibility StatementSkip Navigation HAMILTON, Bermuda, Nov. 21, 2025 /PRNewswire/ --Â White Mountains Insurance Group, Ltd. (NYSE: WTM) announced today that it has commenced a "modified Dutch auction" self-tender offer to purchase up to $300 million in value of its common shares, at a purchase price not greater than $2,050 nor less than $1,850 per share, in cash, less any applicable withholding taxes and without interest. The tender offer commenced today, on November 21, 2025, and will expire at 12:00 mi ...

Financial Performance - White Mountains reported a book value per share of $1,851 as of September 30, 2025, reflecting a 3% increase for Q3 2025 and a 6% increase for the first nine months of 2025[237]. - Comprehensive income attributable to common shareholders was $114 million for Q3 2025, down from $180 million in Q3 2024, and $272 million for the first nine months of 2025, compared to $361 million in the same period of 2024[239]. - The net income attributable to White Mountains's common shareholders for the three months ended September 30, 2025, was $113.8 million, down from $179.0 million in 2024, indicating a decrease of 36.4%[260]. - The comprehensive income attributable to White Mountains's common shareholders for the three months ended September 30, 2025, was $113.5 million, down from $179.8 million in 2024, indicating a decrease of 36.8%[260]. - Total revenues for the three months ended September 30, 2025, were $864.2 million, a slight increase from $839.1 million in the same period of 2024, representing a growth of 3.8%[260]. - The total expenses for the three months ended September 30, 2025, were $685.4 million, an increase from $599.6 million in the same period of 2024, representing a rise of 14.3%[260]. - The total consolidated portfolio return on invested assets was 2.1% in Q3 2025, down from 4.6% in Q3 2024, driven by lower unrealized investment gains from MediaAlpha[255]. - The total consolidated portfolio return on invested assets for the first nine months of 2025 was 6.6%, compared to 9.4% in the same period of 2024[256]. Segment Performance - The Ark/WM Outrigger segment's combined ratio improved to 73% in Q3 2025 from 77% in Q3 2024, with gross written premiums of $366 million in Q3 2025 compared to $374 million in Q3 2024[244]. - Ark reported gross written premiums of $366 million and $2,289 million for Q3 and the first nine months of 2025, respectively, compared to $374 million and $1,943 million in the same periods of 2024[246]. - Pre-tax income for the P&C Insurance and Reinsurance segment was $125.9 million for the three months ended September 30, 2025, compared to $140.8 million in 2024, reflecting a decrease of 10.0%[260]. - The total net written premiums for the Ark/WM Outrigger segment were $287.0 million for the three months ended September 30, 2025, compared to $240.0 million in the previous year, reflecting a growth of 19.6%[265]. - Pre-tax income for the Ark/WM Outrigger segment increased to $270 million in the first nine months of 2025, up from $242 million in the same period of 2024[278]. - The combined ratio for the Ark/WM Outrigger segment improved to 83% in the first nine months of 2025 from 84% in the same period of 2024[278]. Revenue and Investment Highlights - Kudu reported total revenues of $54 million and $139 million for Q3 and the first nine months of 2025, respectively, compared to $47 million and $128 million in the same periods of 2024[250]. - Bamboo's commission and fee revenues increased to $64 million and $167 million for Q3 and the first nine months of 2025, respectively, compared to $43 million and $97 million in the same periods of 2024[252]. - The total goodwill and other intangible assets increased to $1,392.9 million as of September 30, 2025, compared to $805.4 million as of June 30, 2025, marking a significant rise of 73.0%[259]. - The total par value of policies assumed reached $2,208 million in the first nine months of 2025, compared to $2,012 million in 2024, indicating an increase of 9.7%[303]. - The total gross pricing for the first nine months of 2025 was 189 basis points, up from 171 basis points in 2024, reflecting a pricing increase of 10.5%[302]. Cash and Debt Management - White Mountains's common shareholders' equity rose to $4,767.6 million as of September 30, 2025, up from $4,644.5 million as of June 30, 2025, indicating an increase of 2.6%[258]. - Cash reserves as of September 30, 2025, were $289.9 million, a significant increase from $141.2 million as of December 31, 2024[289][290]. - White Mountains' total debt increased to $870.4 million as of September 30, 2025, up from $562.5 million as of December 31, 2024, resulting in a total debt to total capital ratio of 13.2%[379]. - Net cash provided from operations was $497 million for the nine months ended September 30, 2025, compared to $523 million for the same period in 2024[384]. Acquisitions and Strategic Transactions - The Bamboo Sale Transaction values Bamboo at an enterprise value of $1.75 billion, with expected net cash proceeds of approximately $840 million for White Mountains[240]. - White Mountains closed its acquisition of Distinguished on September 2, 2025, paying $224 million in cash consideration[388]. - Bamboo, acquired on January 2, 2024, is a tech-enabled insurance distribution platform focusing on homeowners' insurance in California, enhancing White Mountains's market presence[317]. Market and Economic Conditions - The company emphasizes the importance of market conditions and potential catastrophic events that could impact financial forecasts and operational performance[409]. - The adequacy of loss reserves and related reinsurance is critical for maintaining financial stability and meeting operational targets[409]. - Forward-looking statements indicate expectations for future developments, but actual results may differ due to various risks and uncertainties[406].

WHITE MOUNTAINS REPORTS THIRD QUARTER RESULTS HAMILTON, Bermuda (November 6, 2025) - White Mountains Insurance Group, Ltd. (NYSE: WTM) reported book value per share of $1,851 as of September 30, 2025, an increase of 3% for the third quarter of 2025 and 6% for the first nine months of 2025, including dividends. On October 2, 2025, White Mountains entered into an agreement to sell approximately 77% of its equity interest in Bamboo for cash to CVC Capital Partners and will retain the remainder. Including the e ...

Core Insights - The London Company Small Cap Strategy reported a 1.9% appreciation in its small-cap portfolio for Q3 2025, underperforming the Russell 2000 Index which gained 12.4% [1] - The investor letter highlighted White Mountains Insurance Group, Ltd. (NYSE:WTM) as a key stock, noting its recent performance and market capitalization [2] Company Performance - White Mountains Insurance Group, Ltd. (NYSE:WTM) experienced a one-month return of -0.28% and a 52-week gain of 6.82%, with a closing stock price of $1,899.87 and a market cap of $4.892 billion as of November 3, 2025 [2] - The company faced challenges due to industry headwinds and investment volatility, impacting its stock performance [3] Investment Sentiment - Despite the challenges, The London Company expressed confidence in White Mountains Insurance Group's potential for growth in book value per share through prudent capital allocation [3] - The stock is not among the top 30 most popular stocks among hedge funds, with 20 hedge fund portfolios holding it at the end of Q2 2025, an increase from 19 in the previous quarter [4]