Owner, Dallas Mavericks; chairman, HDNetA billionaire who made his fortune selling his Internet broadcasting business to Yahoo in the first dotcom boom, Cuban's HDnet now produces and televises more hours of high-definition footage each week than any other network. An outspoken blogger, Cuban weighs in forcefully and frequently on controversies like YouTube's copyright practices.
Next up: Cuban, owner of the Dallas Mavericks basketball team, might shake up football by backing a proposed rival to the National Football League.
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