WASHINGTON, D.C. - American Express Co. (AmEx) told the U.S. Supreme Court on Dec. 21 in its opening merits brief that the Second Circuit U.S. Court of Appeals erred in ruling that a mandatory class action waiver clause in AmEx's standardized service contract violated the Federal Arbitration Act (FAA) (American Express Company, et al. v. Italian Colors Restaurant, et al., No. 12-133, U.S. Sup.).