X0306 4 2020-10-30 0 0001818383 MediaAlpha, Inc. MAX 0000776867 WHITE MOUNTAINS INSURANCE GROUP LTD 23 SOUTH MAIN STREET, SUITE 3B HANOVER NH 03755 0 0 1 0 CLASS A COMMON STOCK 2020-10-30 4 S 0 3609894 19.00 D 20532202 I See Footnote On October 27, 2020, MediaAlpha, Inc. (the "Issuer") closed its initial public offering (the "IPO") of its shares of Class A common stock, par value $0.01 per share (the "Class A Common Stock"). In addition to the stock sold by the Issuer in the IPO, White Mountains Investments (Luxembourg) S.a r.l. sold 3,609,894 shares of Class A Common Stock as the selling stockholder at a price of $19.00 per share, which included 618,396 shares of Class A common stock sold pursuant to the option granted to the underwriters by the selling stockholder, which was exercised in full prior to the closing. Includes 20,532,202 share of Class A Common Stock owned directly by White Mountains Investments (Luxembourg) S.a r.l. White Mountains Investments (Luxembourg) S.a r.l. is a wholly owned indirect subsidiary of White Mountains Insurance Group, Ltd. White Mountains Insurance Group, Ltd. has indirect pecuniary interest in the securities held by White Mountains Investments (Luxembourg) S.a r.l. Consequently, White Mountains Insurance Group, Ltd. is deemed to beneficially own the securities held directly by White Mountains Investments (Luxembourg) S.a r.l. The board of directors and senior officers of White Mountains Insurance Group, Ltd. disclaim beneficial ownership with respect to such securities. Joint/Group Beneficial Owners: Bridge Holdings (Bermuda) Ltd. - A.S. Cooper Building, 26 Reid Street, Hamilton HM 11 Bermuda (a wholly owned direct subsidiary of White Mountains Insurance Group, Ltd.) WM International Holdings Ltd - 18 St. Swithin's Lane, London EC4N 8AD United Kingdom (a wholly owned direct subsidiary of Bridge Holdings (Bermuda) Ltd.) White Mountains Investments (Luxembourg) S.a r.l. - 1, rue Hildegard von Bingen, L-1282 Luxembourg (a wholly owned direct subsidiary of WM International Holdings Ltd) White Mountains Insurance Group, Ltd., by Robert L. Seelig, its EVP and General Counsel, /s/ Robert L. Seelig 2020-11-02 Bridge Holdings (Bermuda) Ltd., by Kevin M. Pearson, its Vice President, /s/ Kevin M. Pearson 2020-11-02 WM International Holdings Ltd, by Kevin M. Pearson, its Director, /s/ Kevin M. Pearson 2020-11-02 White Mountains Investments (Luxembourg) S.a r.l., Societe a responsabilite limitee, registered office: 1, rue Hildegard von Bingen, L-1282 Luxembourg, R.C.S. Luxembourg: B 167.137, by Manfred Schneider, its Manager, /s/ Manfred Schneider 2020-11-02