Arch Insurance Group Ltd

Arch Insurance Canada Ltd. 1000 de la Gauchetière, 24th Floor Montreal, QC H3B 4W5,
Arch Insurance Group (Arch), a division of Arch Capital Group Ltd., is a market-leading specialty insurer. We provide a wide range of property, casualty and specialty insurance for corporations, professional firms and financial institutions across the United States and Canada. "Powering Specialty Risk Solutions"​ describes how we drive results for our clients. Specifically, our approach is anchored by:

Company Staff

Chief Executive Officer
Constantine Iordanou has been Chairman of the Board of ACGL since November 6, 2009 and Chief Executive Officer of ACGL since August 2003. He has been a director since January 1, 2002. From January 2002 to July 2003, Mr. Iordanou was Chief Executive Officer of Arch Capital Group (U.S.) Inc. From March 1992 through December 2001, Mr. Iordanou served in various capacities for Zurich Financial Services and its affiliates, including as Senior Executive Vice President of group operations and business development of Zurich Financial Services, President of Zurich-American Specialties Division, Chief Operating Officer and Chief Executive Officer of Zurich-American and Chief Executive Officer of Zurich North America. Prior to joining Zurich, he served as President of the commercial casualty division of the Berkshire Hathaway Group and served as Senior Vice President with the American Home Insurance Company, a member of the American International Group. Since 2001, Mr. Iordanou has served as a director of Verisk Analytics, Inc. (formerly known as ISO Inc.). He holds an aerospace engineering degree from New York University.
Chief Executive Officer
David H. McElroy has served as Chairman and Chief Executive Officer of Arch Worldwide Insurance Group, an executive position of ACGL, since September 2012, and Chairman and Chief Executive Officer of Arch Insurance Group since July 2012. He also serves as a member of the Arch Capital's Executive Strategy Committee. He joined Arch Insurance Group in 2009 as the President of the Financial and Professional Liability Group, which is comprised of the executive assurance, professional liability, surety and healthcare lines. Prior to joining Arch Insurance Group, Mr. McElroy was a Senior Vice President at The Hartford Financial Services Corporation. He joined Hartford in 2000 from the acquisition of the directors and officers and errors and omissions business of Reliance National. He started his career at Chubb. Mr. McElroy is a graduate of Temple University with a B.A. in business administration.
John Mentz is President of Arch Insurance Group Inc., a role he has held since December 2014. In this capacity, Mr. Mentz is responsible for all Arch U. S. underwriting divisions. He joined Arch in October of 2002 as Executive Vice President Construction. In his most recent role, in addition to Construction he had ultimate responsibility for National Accounts Casualty, Alternative Markets, High Excess Workers Compensation and Lenders Products. Prior to Arch, he served in a variety of senior management positions with Zurich and the St. Paul. John is a Fellow of the Casualty Actuarial Society.
Chief Operating Officer
Marc Grandisson was promoted to President and Chief Operating Officer of ACGL on January 1, 2016. Prior to that role, he had been the Chairman and Chief Executive Officer of Arch Worldwide Reinsurance Group from 2005 to 2015, and the Chairman and Chief Executive Officer of Arch Worldwide Mortgage Group from February 2014 to December 2015. He joined Arch Reinsurance Ltd. in October 2001 as Chief Actuary. He subsequently held various leadership roles, including Chief Underwriting Officer and Actuary, President and Chief Operating Officer, eventually being named President and Chief Executive Officer at Arch Reinsurance Ltd. Prior to joining Arch, he held various positions with the Berkshire Hathaway Group, F&G Re, Inc. and Tillinghast/Towers Perrin. He holds a B.Sc. in Actuarial Science from Université Laval in Canada and an M.B.A. from The Wharton School of the University of Pennsylvania. He is a Fellow of the Casualty Actuarial Society and a Member of the American Academy of Actuaries.
Chief Financial Officer
Mark D. Lyons is Executive Vice President, Chief Financial Officer and Treasurer of ACGL. He joined Arch in 2002, and served in various capacities within Arch Insurance U.S. operations, eventually rising to Chairman and Chief Executive Officer of Arch Worldwide Insurance Group. Prior to joining Arch, Mark held various positions at Zurich U.S., Berkshire Hathaway and American International Group. Mr. Lyons has a B.S. in mathematics from Elizabethtown College, is a Member of the American Academy of Actuaries and is an Associate of the Casualty Actuarial Society. He has also completed the Executive Program at the Kellogg School of Management of Northwestern University.