5: Robert Pera — Memphis Grizzlies ($7.1 billion)

Age: 41

Nationality: American

How he made his fortune: The NBA's youngest club owner, Pera formerly worked for Apple, before leaving the company in 2005 after founding wi-fi pioneer Ubiquiti Networks.

Ubiquiti specialize in producing wireless access points and networking equipment to help deliver internet access to rural areas. Pera bought the Memphis Grizzlies in 2012, and the team have since enjoyed its most successful period in its history.

Titles won as owner: N/a.