Mr. Callen was a Senior Advisor at Crestview Partners, a private equity firm, from 2009 through 2016. Previously, Mr. Callen retired as Senior Vice President of Strategic Planning and Business Development for Aetna Inc., where he also served as a Member of the Executive Committee from 2004-2007. In his role at Aetna, Mr. Callen reported directly to the chairman and CEO and was responsible for oversight and development of Aetna s corporate strategy, including mergers and acquisitions. Prior to joining Aetna in 2004, Mr. Callen was a Managing Director and Head of U.S. Healthcare Investment Banking at Credit Suisse and co-head of Health Care Investment Banking at Donaldson Lufkin & Jenrette. During his 20-year career as an investment banker in the healthcare practice, Mr. Callen successfully completed over 100 transactions for clients and contributed as an advisor to the boards of directors and management teams of many of the leading healthcare companies in the U.S. In April 2024, Mr. Callen became an independent director and Chair of the Audit Committee for North Haven Net REIT, a reporting, private REIT focused on investing in primarily net lease commercial real estate assets. Mr. Callen has served on the boards of Symbion, Inc. (short-stay surgery facilities), a Crestview portfolio company; Sunrise Senior Living, Inc. (NYSE:SRZ); Kinetic Concepts, Inc. (NYSE:KCI) (a medical technology company); and HMS Holdings Corp. (NYSE:HSMY). Mr. Callen serves as a Trustee of The Richard Hampton Jenrette Foundation, formerly Classical Homes Preservation Trust.