Larry Ellison (net worth: $42.1 billion)

Born in New York City, raised in Chicago, and living in California, Ellison is the founder and largest shareholder of Oracle, the database company that had revenue of $37 billion in its 2016 fiscal year. He owns about a quarter of the Redwood City, California-based company, as well as stakes in NetSuite and LeapFrog Enterprises, and global real estate assets, including Hawaii’s Lanai island.