December 1996: Santa Fe attorneys Stephen Tinkler and Merit Bennett win a nearly $2 million verdict against Wal-Mart Stores in a case involving sexual harassment of two women at the local Sam's Club.

January 1997: Tinkler and Bennett file two more sexual harassment cases against Sam's Club, a part of Wal-Mart.

1998: Federal judge Martha Vasquez orders Wal-Mart to produce a breakdown by gender of its hourly employees and managers in all the company's stores. Tinkler and Bennett begin looking for a sexual discrimination case to start a class action.

January 2000: Stephanie Odle contacts Tinkler and Bennett, saying that the Sam's Club in Lubbock, Texas, discriminated against her.

March 2000: The lawyers meet with Brad Seligman, founder of the nonprofit law firm, The Impact Fund, to discuss a possible class action.

June 8, 2001: Six law firms identify six plaintiffs from the state of California, including Betty Dukes, and file the class action in U.S. District Court in San Francisco.

June 2004: A federal district judge rules in favor of class certification. Wal-Mart Stores later appeals the case to the 9th Circuit Court of Appeals in California.

February 2007: A three-judge panel of the 9th Circuit affirms the district court's class certification, saying the class can seek lost pay and injunctive relief. Wal-Mart later asks for a rehearing en banc.

March 2009: A panel of 11 judges on the 9th Circuit hears the appeal.

April 2010: The U.S. Court of Appeals for the 9th Circuit rules 6-5 that the lawsuit can proceed as a jumbo class action.

Aug. 26, 2010: Wal-Mart appeals the decision to the U.S. Supreme Court.

Oct. 25, 2010: This is the deadline for plaintiffs' attorneys to file their opposition to the cert petition.