In Ohio v. American Express Co., the United States Supreme Court had its first knowing encounter with what it incorrectly viewed as a two-sided platform in the context of American Express’ Non Disclosure Provisions (NDP). Under these provisions merchants accepting the American Express card for payment are not permitted to inform consumers that other cards charge merchants less for their use and that this could be reflected in the final price paid. The opinion includes poor reasoning, a lack of attention to precedent, and bad news for those who thought antitrust law was due for a revival. Yet, and perhaps surprisingly, the outcome may be correct. Part II of this Essay very briefly summarizes the antitrust landscape in order to provide an und...