Mouthy Billionaire Mark Cuban Fined for Using Twitter 12.92K Owen Thomas 03/29/09 04:08PM Filed to: Shut Up, Twitter Shut Up, Twitter Mark Cuban Valleywag Deadspin Dallas Mavericks twitter Sports The NBA has fined Dallas Mavericks owner Mark Cuban, the dotcom billionaire, $25,000 for slagging referees on Twitter Friday. His Twittered response: The league has found a way for Twitter to make money.