Illinois Tool Works v. Independent Ink, Inc. (U.S. Supreme Court)

In an antitrust action alleging that a defendant engaged in illegal “tying” by conditioning the sale of one product on the purchase of a second product, the plaintiff ordinarily must show that the defendant had “market power” in the former product. Under the Supreme Court’s decisions in International Salt Co. v. United States (1947) and United States v. Loew’s, Inc. (1962), however, the defendant was presumed to have market power if it had a patent for that product. We successfully convinced the Supreme Court to grant certiorari and overturn those decisions, vacating a decision against our client. As a result, market power can no longer be presumed from the mere existence of a patent; instead, the plaintiff in any tying case must prove that the defendant had market power in the tying product.