He is the co-founder of XTO Energy and co-chairman of the Texas Rangers Major League Baseball (MLB) team.
In 1985, Simpson founded Cross Timbers Oil Company and has served as Chairman of the Board since July 1, 1996.
They served mainly as senior consultants, an arrangement continued after Greenberg resigned in 2011, making Ryan the undisputed day-to-day head of the franchise.
However, Davis and Simpson mostly left the Rangers in the hands of general manager Jon Daniels and have rarely interfered.
Hear Me, the debut album from up and coming rock musician Kyle Sherman, was the first recording produced by the company.