This is an appeal from an order of the United States District Court for the Northern District of California, No. C93-4152 SBA (June 3, 1994), granting a patent holders motion for a preliminary injunction in a patent infringement suit. Although the district Judge engaged in a detailed analysis that makes us reluctant to second-guess her judgment, we have concluded that the court committed legal errors that require reversal of the order granting preliminary injunctive relief.