AGREEMENT AND PLAN OF MERGER between ALTERRA CAPITAL HOLDINGS LIMITED MARKEL CORPORATION and COMMONWEALTH MERGER SUBSIDIARY LIMITED Dated as of December 18, 2012Agreement and Plan of Merger • December 19th, 2012 • ALTERRA CAPITAL HOLDINGS LTD • Fire, marine & casualty insurance
Contract Type FiledDecember 19th, 2012 Company IndustryAGREEMENT AND PLAN OF MERGER, dated as of December 18, 2012 (this “Agreement”), among Alterra Capital Holdings Limited, a Bermuda exempted limited liability company (the “Company”), Markel Corporation, a Virginia corporation (“Parent”), and Commonwealth Merger Subsidiary Limited, a Bermuda exempted company and a wholly owned subsidiary of Parent (the “Merger Sub”).