Thomas Frist Jr., MD, has a net worth of $24.9 billion as of Jan. 31, according to Forbes' net worth tracker.
After beginning his medical career as an Air Force flight surgeon, Dr. Frist founded Nashville, Tenn.-based HCA Healthcare with his father in 1968. He now owns more than 20% of the company.
While he no longer holds an executive position, his two sons are on the board.
Forbes assigned Dr. Frist a "self-made score" of 7 — he had a hand in starting his company but got a head start from wealthy parents and a moneyed background.
HCA includes 182 hospitals and 2,300 care sites, including freestanding emergency rooms, urgent care centers, diagnostic and imaging centers, walk-in clinics and physician clinics. The company has more than 150 ASCs.