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White Mountains INSURANCE GROUP CONTACT : Todd Pozefsky ( 203 ) 458-5807 WHITE MOUNTAINS REPORTS FIRST QUARTER RESULTS HAMILTON , Bermuda ( May 10 , 2021 ) - White Mountains Insurance Group , Ltd. ( NYSE : WTM ) reported book value per share of $ 1,231 and adjusted book value per share of $ 1,242 as of March 31 , 2021. Book value per I share and adjusted book value per share both decreased 2 % in the first quarter of 2021 , including dividends . Manning Rountree , CEO , commented , " We are off to a bit of a slow start in 2021 , with ABVPS down 2 % in the first quarter . The decline was largely driven by two items— ( i ) a mark - to - market decline in our MediaAlpha position ( which has since rebounded ) and ( ii ) a loss triggered by NSM's sale of the Fresh Insurance motor business . Our underlying operating results were sound . BAM enjoyed its strongest first quarter on record , driven by primary market penetration and another significant assumed reinsurance transaction . Ark wrote $ 405 million of gross written premiums in the quarter , up more than 2x year over year , with renewal pricing up more than 10 % . Ark's adjusted combined ratio was 108 % in the quarter , impacted by heavy cat losses , chiefly related to Winter Storm Uri . NSM posted solid growth in both pro forma controlled premiums and pro forma adjusted EBITDA . Kudu posted solid growth in revenues from participation contracts and adjusted EBITDA . Excluding MediaAlpha , our investment portfolio was up 0.7 % in the quarter . Reflecting $ 160 million of net proceeds from the MediaAlpha secondary offering in March , we finished the quarter with roughly $ 300 million in undeployed capital . " Comprehensive loss attributable to common shareholders was $ 74 million in the first quarter of 2021 , compared to $ 132 million in the first quarter of 2020. Results in the first quarter of 2021 were driven primarily by $ 42 million of net realized and unrealized investment losses from White Mountains's investment in MediaAlpha ( as the MediaAlpha share price declined from $ 39.07 at December 31 , 2020 to $ 35.43 at March 31 , 2021 ) and a loss of $ 29 million related to NSM's sale of its Fresh Insurance motor business . Results in the first quarter of 2020 were driven primarily by negative investment returns as equity markets declined in reaction to the COVID - 19 pandemic . MediaAlpha On March 23 , 2021 , MediaAlpha completed a secondary offering of 8.05 million shares at $ 46.00 per share ( $ 44.62 per share net of underwriting fees ) . In the secondary offering , White Mountains sold 3.6 million shares for net proceeds of $ 160 million . Following the completion of the offering , White Mountains owns 16.9 million shares , representing a 29 % basic ownership interest ( 26 % on a fully - diluted / fully - converted basis ) . At the March 31 , 2021 closing price of $ 35.43 per share , the value of White Mountains's remaining stake in MediaAlpha was $ 600 million . Subsequent to the secondary offering , each $ 1.00 per share increase or decrease in the market price of Media Alpha will result in an approximate $ 5.50 per share increase or decrease in White Mountains's book value per share and adjusted book value per share . 1