Sean Lenahan

Sean Lenahan currently serves as the Head of Portfolio Operations at Sunstone Partners since October 2025. Prior to this role, Sean was an Operating Partner at Bregal Sagemount, where responsibilities included board membership and collaboration with Founders and CEOs to enhance growth and performance. Sean also held the position of Operating Partner at The Riverside Company, focusing on the transformation and growth of portfolio companies across various industries, including software and tech-enabled services. In earlier positions, Sean served as Principal at Regent Equity, Chief Executive Officer at Pegasus Solutions, Vice President and Associate at Deloitte and Lazard, and worked as an Associate at Alvarez & Marsal. Sean's career commenced as a Captain in the United States Air Force, following an education in Astronautical Engineering and Mathematics from the United States Air Force Academy and an MBA from The Wharton School.