A spokesperson confirmed Wednesday that T. Boone Pickens has passed away.
Pickens amassed a fortune as an oil tycoon and gave much of it away as a philanthropist.
The president of Oklahoma State University is describing Pickens as the "ultimate Cowboy" following the death of one of the university's most famous alums.
The football stadium where the Cowboys play underwent a massive renovation after a Pickens donation and now bears his name.
Pickens was born in Holdenville and had been sin declining health since 2017.