The biggest gender discrimination suit out there made it past a major hurdle on Monday. Wal-Mart’s women, who filed suit in 2001 for a host of complaints of sex bias, got a ruling from the U.S. Court of Appeals for the Ninth Circuit that allows their case to proceed as a class-action suit. That means that the six named plaintiffs can represent at least hundreds of thousands of their fellow Wal-Mart employees, and maybe 1.6 million of them. The Ninth Circuit ruling also gives the women more leverage in settlement negotiations, as Steven Greenhouse points out in the NYT . The appeals court was closely divided, 6-5, and the underlying legal issue, about what plaintiffs need to show to launch a giant class action, is actually really interesting and contested. Wal-Mart said it would appeal to the Supreme Court. For today, though, the women heading up this suit can take a moment to bask in the glow. Betty Dukes says she was denied the chance to advance at the company after six years of hard work and top performance reviews. This looks like part of a larger pattern: The plaintiffs say that 65 percent of Wal-Mart’s hourly employees (less pay, less status) are women, compared with about 33 percent of management. Liza Featherstone wrote a book about the case-more from her here , and background from walmartwatch.com.