The U.S. Supreme Court is dashing a bid by T-Mobile and AT&T to stave off a class-action lawsuit challenging the carriers' policies against unlocking mobile phones. The justices declined to review an October decision by the California Supreme Court that cleared the way for a lawsuit that attorneys claimed could represent "millions" of California customers. In response to similar lawsuits, Verizon and Sprint, both CDMA carriers, have agreed to provide the software code to unlock cell phones after customers nationwide have completed their original contract.