Document Type


Publication Date


Publication Citation

41 Connecticut Law Review 493 (2008)


Broadly speaking, courts and commentators have offered two theories to explain the relationship between the literal scope of a patent claim and after-arising technology (AAT), i.e. technology that is not discovered until after a claim has been filed. The fixation theory asserts that claim scope is and/or should be fixed on the date a claim is filed and that this fixation makes it impossible for the claim to encompass AA T because a claim must grow in some sense after the filing date in order to encompass AA T. In stark contrast, the growth theory argues that literal claim scope does and/or should encompass AAT on a routine basis and that literal claim scope therefore cannot be fixed on the date of filing.

Finding neither of these theories satisfying, either descriptively or normatively, this Article rejects them. More specifically, it rejects a logical premise that both theories share, namely that simultaneous fixation of and growth in literal claim scope is a logical impossibility. The concept of the literal scope of a claim is ambiguous in several ways. Courts can--and routinely do-fix one concept on the date of filing to achieve certain goals, such as furthering public notice, while at the same time allowing a distinct concept to grow and absorb AA T to achieve other goals, such as providing sufficient incentives. Every time a court addresses whether AAT falls within the literal scope of a valid patent claim, it necessarily constructs the things claimed by a patent and defines the nature of the meaning that permits the claiming language to describe those things. Literal claim scope can remain fixed and yet literal claim scope can grow to encompass AA T at the same time (in different senses of the concept of literal claim scope, of course) provided that a court makes tactical decisions in the course of constructing things and defining meaning.