Rafael reported on Saturday that Mayweather could be stripped of the belt after missing the deadline to pay the sanctioning body a $200,000 fee.
Mayweather originally planned to not accept the title as part of his post-fight pledge to vacate all his titles so younger boxers could have a chance at the belts. But when he did accept the WBO prize, he was required to pay the fee by last Friday in order to keep the title.
A championship committee vote was held on Monday and made the decision to strip Mayweather of the belt, according to Rafael. It is now expected to go to Timothy Bradley Jr., who won the organization's interim 147-pound title in a fight with Jessie Vargas on June 27.
Mayweather currently holds the welterweight and super welterweight titles for both the WBA and WBC.