Net worth: $1.8 billion
Worldwide billionaires ranking: No. 1,511
Forbes 400 note: Richison was not listed in 2018's Forbes 400 list. However, he had a net worth of $1.5 billion in March 2019's billionaires list on Forbes.
Forbes writes: "Richison founded a non-profit, The Green Shoe Foundation, which aims to improve people's well-being through workshops, counseling and therapy sessions."
Did you know: "Richison's 2015 gift of $10 million to his alma mater, the University of Central Oklahoma, was the largest in the university's history."
Quote: "Technology is a huge industry. Most of the major companies on the New York Stock Exchange and Nasdaq are technology companies. I just hope over time Oklahoma and Oklahoma City are able to attract technology companies and keep our talent so that we can create technology companies here. It's a huge industry that I think the state is missing out on," he told The Oklahoman in 2015.