More than six years before the biggest sex discrimination lawsuit in history was filed against Wal-Mart Stores, the company hired a prominent law firm to examine its vulnerability to just such a suit.

The law firm, Akin Gump Strauss Hauer & Feld, found widespread gender disparities in pay and promotion at Wal-Mart and Sam’s Club stores and urged the company to take basic steps  like posting every job opening and creating specific goals to promote women and minorities  to avoid liability.

The 1995 report said that women employed by Wal-Mart earned less than men in numerous job categories, with men in salaried jobs earning 19 percent more than women. By one measure, the law firm found, men were five and a half times as likely as women to be promoted into salaried, management positions.

Without significant changes, the lawyers said in their confidential analysis, Wal-Mart “would find it difficult to fashion a persuasive explanation for disproportionate employment patterns.”