That leaves seven players, most notably Phil Mickelson and Bryson DeChambeau, along with LIV Golf, as plaintiffs in the lawsuit.
The four who withdrew their names are Carlos Ortiz, Abraham Ancer, Pat Perez and Jason Kokrak.
The amended complaint was filed Friday afternoon in the U.S. District Court in Northern California.
Three players still on the lawsuit – reigning Australian Open champion Matt Jones, Talor Gooch and Hudson Swafford – previously sought a temporary restraining order to play in the FedExCup Playoffs.
The judge denied their request two weeks ago.
The lawsuit claims the PGA Tour has used monopoly power to try to squash competition and has unfairly suspended players.
Greg Norman, the CEO of LIV Golf, has said the league would fully support the players in any legal action they pursued.
In the amended complaint, LIV Golf argues…
