On February 12, 2019, the Board of Directors of HollyFrontier Corporation expanded the size of the Board from ten to eleven members and appointed Craig Knocke as an independent director to the Board, in each case effective February 13, 2019. Mr. Knocke, 49, is a co-founder and a Director of Turtle Creek Trust Company, a private trust and investment management firm, since 2009. He currently serves as the Chief Investment Officer and has served as a Portfolio Manager at Turtle Creek Management, LLC, a registered investment advisory firm based in Dallas, Texas, since 2007. In addition, on February 13, 2019, Franklin Myers was appointed as Chairman of the Board. The Company's former Chairman of the Board, Michael C. Jennings, will continue to serve as a member of the Board.