The U.S. Supreme Court has ruled the National Labor Relations Board lacked authority to issue decisions when it had just two members. In a 5-4 opinion handed down on June 17, the court likely invalidated nearly 600 NLRB judgments from January 2008 to March 2010. It said a minimum quorum of three members is necessary.

Unions criticized the court’s ruling, saying it will delay action on important labor disputes. But Denise Gold, the Associated General Contractors’ associate general counsel, says the decision should have a minimal impact.

The Senate on June 22 confirmed two NLRB nominees: Republican Brian Hayes and Mark Pearce, a Democrat. Pearce has been on the board since April through a recess appointment.