Phil Mickelson has asked a federal judge to withdraw his name from the lawsuit filed by LIV Golf Invitational Series players against the PGA Tour, along with three others.
Talor Gooch, Ian Poulter and Hudson Swafford also want to be dismissed from the antitrust lawsuit, leaving just three players from the original 11 who filed against the Tour.
Mickelson, one of the most prominent defectors from to LIV Golf this year, had been expected to remove his name after the breakaway series joined the suit as a plaintiff.
Only Bryson DeChambeau, Peter Uihlein and Matt Jones now remain as individuals.
The lawsuit accuses the PGA Tour of benefiting from operating as a monopoly and alleges it improperly suspended LIV Golf players from its events.
"Nothing has changed," LIV Golf spokesman Jonathan Grella said in a statement.
"The merits of the case – the PGA Tour's anticompetitive conduct – still stand and will be fully tested in court. And we look forward to that.
"LIV stands with the players whom the PGA Tour has treated so poorly, but we also recognise that to be successful, we no longer need a wide array of players to be on the suit.
"We have our players' backs and will press our case against the PGA Tour's anticompetitive behaviour."