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White Mountains INSURANCE GROUP CONTACT : Todd Pozefsky ( 203 ) 458-5807 WHITE MOUNTAINS REPORTS THIRD QUARTER RESULTS HAMILTON , Bermuda ( November 8 , 2021 ) - White Mountains Insurance Group , Ltd. ( NYSE : WTM ) reported book value per share of $ 1,162 and adjusted book value per share of $ 1,176 as of September 30 , 2021. Book value per share and adjusted book value per share both decreased 9 % in the third quarter of 2021. For the first nine months of 2021 , book value per share decreased 8 % and adjusted book value per share decreased 7 % , including dividends . Manning Rountree , CEO , commented , " ABVPS was down 9 % in the third quarter , driven by the decrease in MediaAlpha's share price . Excluding the mark to market losses at MediaAlpha , ABVPS was up nicely , reflecting solid performance at our operating companies . BAM produced $ 28 million of total premiums and member surplus contributions , as insured penetration remained high and pricing improved . Ark produced an 89 % adjusted combined ratio while increasing gross written premiums 79 % year over year . NSM posted record levels of both pro forma controlled premium and pro forma adjusted EBITDA , driven by solid growth in its existing verticals and the J.C. Taylor acquisition . Kudu posted strong growth in adjusted EBITDA and $ 19 million of unrealized gains in the fair value of its portfolio , while deploying $ 130 million into new transactions . Excluding MediaAlpha , our investment portfolio returned 1.4 % in the quarter . We completed $ 87 million of share repurchases during the quarter and finished the third quarter with roughly $ 450 million of undeployed capital . " Comprehensive ( loss ) income attributable to common shareholders was $ ( 373 ) million and $ ( 308 ) million in the third quarter and first nine months of 2021 compared to $ 237 million and $ 220 million in the third quarter and first nine months of 2020. Results in the third quarter and first nine months of 2021 were driven primarily by $ 397 million and $ 326 million of net realized and unrealized investment losses from White Mountains's investment in MediaAlpha . Results in the third quarter and first nine months of 2020 were driven primarily by $ 305 million and $ 355 million of net investment income and unrealized investment gains from White Mountains's investment in MediaAlpha . MediaAlpha White Mountains owns 16.9 million shares of MediaAlpha , representing a 28 % basic ownership interest ( 26 % on a fully - diluted / fully - converted basis ) . At the September 30 closing price of $ 18.68 , which was down from $ 42.10 at June 30 , the value of White Mountains's investment in MediaAlpha was $ 316 million , which was down from $ 713 million at June 30 , 2021. This accounted for a decrease of $ 131 in book value per share and $ 132 in adjusted book value per share in the quarter . At our current level of ownership , each $ 1.00 per share increase or decrease in the share price of MediaAlpha will result in an approximate $ 5.60 per share increase or decrease in White Mountains's book value per share and adjusted book value per share . At the October 2021 month - end closing price of $ 17.53 per share , the fair value of White Mountains's investment in MediaAlpha was $ 297 million . Our focus remains on MediaAlpha's intrinsic value , not on fluctuations in its share price . We encourage you to read MediaAlpha's third quarter earnings release and related shareholder letter scheduled for November 10 , 2021 , which will be available on MediaAlpha's investor relations website at www.investors.mediaalpha.com . 1