The news came amid the second round of the U.S Open, and 10 days after PGA Tour commissioner Jay Monahan appeared with PIF governor Yasir Al-Rumayyan for a CNBC interview explaining the parties' decision to pursue a new, for-profit entity controlling the world of professional golf.

Crucially, the motion to dismiss was filed with prejudice, meaning neither LIV's antitrust case against the PGA Tour nor the Tour's countersuit can be reopened in the future.

That is important because, despite the shocking news on June 6 that caught the golf world off-guard, the so-called merger is far from a done deal.

U.S senators Elizabeth Warren and Ron Wyden have asked US Attorney General Merrick Garland to oppose the PGA-PIF deal if federal antitrust laws were violated.

The Wall Street Journal reported on Thursday the union "will fall apart entirely" if the sides are unable to iron out specific terms, of which there are currently few.

The proposed combined entity would see Al-Rumayyan serve as chairman and Monahan as CEO, with the PGA Tour appointing a majority of the board and holding a majority voting interest.

Monahan took a medical leave from his job on Tuesday, with PGA Tour president Tyler Dennis and chief operating officer Ron Price guiding the organisation in his absence.