United States patent law’s view on the need for a physical embodiment of the invention, and the continued production and use of an embodiment, has varied over the last two centuries. In the early days, the requirement for “physicalism” was high, with the inventor being required to actually reduce the invention to practice prior to patenting, and enforceability was tied to “working” the claimed invention. By the early 1900s, these requirements of physicalism disappeared. This changing view on physicalism speaks volumes as to which major patent theory the law emphasizes, with physicalism supporting the incentive to invent theory and the shift away from this physicalism bringing the disclosure theory to the forefront. This interplay between physicalism and patent theory, particularly regarding post-issuance physicalism, not only explains the past, it also describes the current discourse regarding, and legal reaction to, non-practicing entities (“NPEs”). Decisions such as eBay v. MercExchange, denying exclusivity to NPEs, once again emphasize physicalism and are interrelated to the incentive to invent and, in turn, downplay the disclosure theory and question its current validity as a patent policy goal.
Christopher A. Cotropia, Physicalism and Patent Theory, 69 Vand. L. Rev. 1543 (2016).