C.R. Bard, Inc. v. Advanced Cardiovascular Systems, Inc.

Bard (plaintiff) held a patent on a catheter-based angioplasty method; ACS (defendant) sold a similarly designed catheter with ten openings, and Bard sued for contributory infringement, arguing surgeons' use of ACS's catheter infringed Bard's method patent. ACS presented evidence that roughly half of angioplasty-requiring blockages sit less than three centimeters from the coronary artery's entrance, meaning its catheter could often be positioned with all openings inside the aorta — a use ACS claimed was non-infringing; the district court nonetheless granted Bard summary judgment finding contributory infringement, and ACS appealed.