Patent Infringement as Trespass

The now-conventional account of patent law holds that infringement is a strict liability offense, meaning that intent is not an element of an infringement claim. This account heightens the apparent injustice of patent law\u27s special knowledge problem, that as ambiguous descriptions of intangible resources, patent claims do not sufficiently make potential infringers aware of a patentee\u27s right to exclude. Particularly in the age of so-called patent thickets, clusters of patents of variable merit which are indistinguishable from each other and from prior art, strict liability, or infringement seems rather hard. These problems reflect a conceptual misunderstanding. When infringement is understood as a species of trespass, as it was long described in American law, the various aspects of infringement doctrine fall into place. Common law traditionally recognizes three forms of trespass. Together, those three forms explain all of infringement doctrine as a coherent whole and resolve the apparent injustices that seem problematic on the conventional account of infringement. They also suggest that traditional equitable maxims should be used to determine when injunctive relief is appropriate to remedy ongoing, willful infringement