A Brief Defense of the Written Description Requirement
Yale Law Journal Online, Vol. 119, p. 127, 2010
19 Pages Posted: 14 Nov 2009 Last revised: 17 Mar 2022
Date Written: November 12, 2009
This essay provides a brief defense of the much maligned "written description" requirement in patent law. Many argue that there is no such requirement, and that a patent specification that enables a person having ordinary skill in the art (the PHOSITA) to make and use the invention is sufficient, even if the specification contains no description of the invention. This essay briefly describes the dispute, and then raises an important but under-theorized argument in favor of a separate written description requirement. The essay accepts the persuasive grammatical reading of the statute proposed by opponents of a separate written description requirement. This reading suggests that a patent disclosure is sufficient so long as the PHOSITA can practice the invention. However, while enablement is necessary to satisfy Section 112, it is not sufficient. Even if the specification enables a PHOSITA to practice the invention, the applicant is not relieved of the obligation to identify the invention. Instead, the specification must contain a “description of the invention” even if such description would only serve to reinforce other parts of the disclosure that enable one to make and use the invention. This reading of the statute is consistent with the grammatical breakdown of Section 112. It is also the preferred interpretation, because a description of the invention fulfills an important purpose in the patent system. Finally, the essay considers the Ariad v. Eli Lilly case currently pending before the Federal Circuit and concludes, perhaps surprisingly, that under the vision of written description presented in this essay the claims at issue may well be described.
Keywords: patent, written description, enablement, invention, conception, priority
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