SAN FRANCISCO — A feisty Ninth Circuit U.S. Court of Appeals peppered lawyers for Wal-Mart and a gigantic class suing over gender discrimination, with neither side emerging Tuesday as the clear victor.

Gibson, Dunn & Crutcher partner Theodore Boutrous Jr. played to a packed house as he argued that the district court applied the wrong standard in granting certification to female Wal-Mart workers. He quickly ran into Ninth Circuit Judge Marsha Berzon, a former labor lawyer who aggressively pointed out that the women didn’t have to prove actual discrimination at this point, just commonality of the class.