The common law plays a prominent role in the development of American patent law. Judicial stewardship of the patent space can be seen as an institutional advantage, one that compares favorably to punctuated, and potentially more distortive or inartful, congressional action. The common law allows for a certain flexibility, and despite its deep allegiance to tradition, crust forms more readily on statutory law than the common law. One of the tools that reflects this institutional litheness is the use of legal fictions, which have been employed by judges in various areas of the law seemingly since the beginning of the common law process. A fiction serves a variety of purposes, but its principal use is to allow the judge to construct rules and to reach holdings that perhaps, without the veil of fiction, would not be as feasible within the existing confines of stare decisis or the formalism associated with well-worn doctrine.

At first blush, it may seem odd that legal fictions would find a comfortable home in patent law, given that patent jurisprudence is so closely related to technological fields steeped in empirical certainty. Beyond the doctrinal arcana and scientific principles, from a greater remove, patent law is like any other area of the law where the judge plays a prominent role. Yet what is interesting about patent law is its relationship with information, particularly how it seeks to regulate exclusivity of and access to technical information. Legal fictions in patent law express themselves in this context, taking the familiar forms of presumptions, deemings, and other “techniques” to either express preferences relating to administrability of patentability requirements such as novelty and the public use doctrine, two of the public domain’s gatekeepers, or mask normative choices pertaining to claim scope that play out along the ex ante/ex post incentive continuum. With respect to the former, patent law treats information in a manner that serves a protective function that shields the public domain by erecting presumptively omniscient sentries around the domain’s perimeter. Regarding the latter, information is employed to further a disseminative function, which not only enriches the global storehouse of technical knowledge but also limits claim scope through the doctrines of commensurability and prosecution history estoppel. This Article explores how legal fictions are constructed to bolster these functions.


Common Law, Patent Law, Legal Fiction, Technical Information, Novelty, Public Use Doctrine, prosecution history estoppel, enablement, and doctrine of equivalents

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Vanderbilt Law Review


COinS Craig Allen Nard Faculty Bio