The U.S. Supreme Court has agreed to review an appellate court decision that reversed a ruling against American Express Co. in an antitrust case.

After an appeals court tossed aside a lower court's decision, saying the lower court's analysis of American Express' market power and its finding that the company adversely affected competition were wrong, 11 states opted to take the case to the Supreme Court. Regulators had alleged that the company's card policy, which stops merchants from steering consumers to use cheaper cards on other networks such as Visa Inc. and Mastercard Inc., stifled competition.

The states said the appeals court ruling is at odds with Supreme Court precedent, adding that the credit card industry's services to merchants and cardholders were not exchangeable.