Top Rank CEO Bob Arum says he submitted a formal request for an inquiry to the Nevada attorney general's office on Monday.
Bradley took the welterweight title from defending champion Pacquiao on Saturday night, ending the Filipino fighter's remarkable seven-year unbeaten run.
Bradley won 115-113 on two scorecards, while losing by the same margin on the third. The decision was roundly booed by the crowd at the MGM Grand arena.
Arum says the only way to restore fans' confidence in boxing is to have an independent investigation.
The attorney general's office did not immediately return a message seeking comment Tuesday.