Jim McKelvey cofounded payments firm Square with Jack Dorsey in 2009 after he had trouble selling a $2,000 art piece from his studio. He currently ranks #378 on the Forbes 400 list of the world's richest people.
McKelvey remains on Square's board but has started a new company, Invisibly, which powers micropayments for journalism and publishing.
A serial entrepreneur, he has started at least seven companies, ranging from a CD cabinet maker to a glass-blowing studio.
He also sits on the board of the Federal Reserve Bank of St. Louis and started a nonprofit, LaunchCode, to teach people how to program.
In March 2020, he released "The Innovation Stack," a book detailing what it means to be a true entrepreneur and what it takes to build a resilient, world-changing company.