Attorney Brad Seligman was on a hunt to find out whatever he could about Wal-Mart Stores Inc. after hearing about a potential claim of alleged sex discrimination against the retailer in 1999.

“I called up my friend, another attorney, and he immediately said, ‘evil empire,’ ” said Seligman, executive director and founder of a nonprofit group called The Impact Fund, located in Berkeley, Calif. “ Then I called another friend, who is an economist, and he also indicated the same.”