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Jonathan Mariner

Jonathan Mariner is a private investor, entrepreneur, and independent board member with more than two decades of experience working in major league sports. He’s currently the Founder and President of TaxDay, LLC, a private software firm that helps users track their multi-state travel for tax purposes. His passion for tax and accounting solutions is what brought him to be part of Xendoo.

Jonathan retired from Major League Baseball, Office of the Commissioner in 2016, having previously served as Executive VP and CFO from March 2002 to December 2014; and, as Chief Investment Officer, from January 2015 until May 2016. His career in professional sports started in 1992 as Executive Vice President and CFO of the Florida Marlins Baseball Club. Jonathan concurrently served as Vice president and CFO of the Florida Panthers Hockey Club for the team’s initial startup and inaugural seasons in 1993 and 1994, and as Vice President and CFO for Pro Player Stadium, the multi-use sports complex that was home to both the Florida Marlins and Miami Dolphins at the time.

Jonathan currently serves on the Board of Directors of Ultimate Software (Nasdaq: ULTI) as the Chair of the Audit Committee. Jonathan also serves on the Boards of Directors of the following private companies: McGraw Hill Education; and Investors Exchange (IEX, the new public stock exchange featured in Michael Lewis’ book, “Flash Boys” He also serves on the following charitable boards: Little League Baseball International; and the Board of Trustees of the University of Virginia’s Darden School of Business.

Jonathan graduated from the University of Virginia with a bachelor’s degree in accounting and received his MBA from Harvard Business School, and is a former Certified Public Accountant.