Wal-Mart asked the Supreme Court Wednesday to throw out a class-action lawsuit against it that the retailer says is the largest employment suit ever.
The 9th U.S. Circuit Court of Appeals ruled in April that Wal-Mart should face charges in court that it pays women less than men for the same jobs. The lawsuit, which covers all female workers at Wal-Mart since 1998, could cost the company billions if it loses.

"It's an extremely significant case," says former Equal Employment Opportunity Commission general counsel Eric Dreiband, who is not involved in the lawsuit. "The rights of millions of women are at stake."

Wal-Mart, the world's largest private employer, says the case raises serious issues about procedures governing class-action lawsuits.

"The class is larger than the active-duty personnel in the Army, Navy, Air Force, Marines and Coast Guard combined — making it the largest employment class action in history by several orders of magnitude," Wal-Mart argued in its petition to the Supreme Court.