Ohio v. American Express: Assessing the Threat to Antitrust Enforcement

By Michael L. Katz 

One year later, the U.S. Supreme Court’s opinion in Ohio v. American Express remains a glaring example of the misapplication of economic theory coupled with disregard for the factual record. If applied to other cases, the approach to antitrust analysis stated in that opinion would threaten sound enforcement. In this note, I assess the breadth and likelihood of that threat. I observe that a wide variety of firms could fall under the Court’s definition of a transaction platform and, thus, be candidates for application of the American Express approach. However, in recently decided Apple v. Pepper, neither the majority opinion nor the dissent applied the American Express approach despite the fact that Apple App Store clearly is a transaction platform.