Of Fences and Definite Patent Boundaries

Abstract

Patent claims are supposed to mark the boundaries of a patent clearly so that competitors and follow-on innovators can avoid infringement. But commentators routinely lament the failure of patent claims to adequately perform this notice function. In numerous calls for patent reform, courts and scholars have contrasted the indeterminacy of patent claims with the clarity of real property boundaries. The Supreme Court recently echoed this sentiment in Nautilus v. Biosig Instruments. In Nautilus, the Court heightened the patent requirement of claim definiteness and reversed Federal Circuit precedent, which had allowed many ambiguous claims to survive invalidity challenges.

This Article analyzes how the oft-invoked contrast between ambiguous patent claims and clear property boundaries (e.g.,“fences”) bears on two controversial issues in patent scholarship: (1) the problem of uncertain claim scope and (2) the role of “property-talk” — using traditional property law as metaphor, rhetorical device, or doctrinal guide — in patent law. Many intellectual property scholars view property-talk suspiciously, because it usually supports strengthening patent holders’ rights at the expense of competitors and follow-on innovators.

This Article’s primary contribution is to complicate the prevailing view of property-talk in patent law as uniformly favoring patent holders. This Article focuses on the claim uncertainty problem and recent changes to patent law’s definiteness requirement. In this context, property-talk — specifically, the metaphor of clear, fixed, and determinate real property boundaries — supports requiring patentees to draft clearer claims and provide better notice to competitors and follow-on innovators about the boundaries of a patent.