Fence Posts or Sign Posts: Rethinking Patent Claim Construction
Patent law is bogged down in the minutia of claims construction. Claimconstruction is central to every patent dispute, but it has not providedthe hoped-for certainty or notice to competitors. Quite the contrary:disputes about the importance of inventions and the scope of patents havebeen replaced by labyrinthine wrangling over words written by lawyers. Theflaws of claim construction result largely from the problems attending"peripheral claims," that is, claims that purport to set the outermostboundaries of patent rights. In this paper, we argue that the way for thepatent system to move ahead may be by looking behind, to the practice of"central claiming" that was prevalent before 1870, and which was used inmany countries through the late twentieth century. Rather than relying onthe illusion of peripheral "fence posts," patent law may do better to onceagain look to stability of central "sign posts." We examine the failure ofperipheral claiming, the benefits of central claiming, and several hybridmeasures that might be adopted, either in the process of moving fromfence-posting to sign-posting, or as improvements over the current systemthat still stop short of fully adopting central claiming.