Wal-Mart is facing what could be the largest discrimination lawsuit ever brought against a private U.S. employer. Six female employees of Wal-Mart have filed a lawsuit in federal court in San Francisco charging the retailing giant with widespread discrimination against women. They are asking that the case be certified as a class action on behalf of 700,000 current and former female employees at Wal-Mart stores across the country. The workers claim that women were regularly assigned to the lowest paying jobs with little chance of advancement and that women represent 72% of hourly sales employees but just one-third of managers. Wal-Mart has denied the allegations and said that when store department managers are included in the tally, women hold about half of the company’s management jobs.