WDWDW. A sign is posted in Wal-Mart’s corporate legal department with those letters, which stand for “What did we do wrong?”-a homey mantra handed down from the company’s legendary founder, Sam Walton.

When Wal-Mart is in the wrong, Sam believed, the company should pay, says Wal-Mart Asst. General Counsel Ron Williams. But when the answer to WDWDW is “nothing,” Wal-Mart fights hard.