U.S. patent law Edit
The written description requirement of 35 U.S.C. §112 ensures that the inventor actually has invented what the patent application claims; the inventor must describe the invention sufficiently to show that he or she is in possession of the invention. The written description requirement derives in part from considerations of patent breadth. By requiring patent applicants to provide a description sufficient to show that they are in possession of the invention, the requirement protects against overbroad claim amendments. Indeed, the Federal Circuit has described one "policy-based rationale" for the description requirement as follows:
|“||Adequate description of the invention guards against the inventor's overreaching by insisting that he recount his invention in such detail that his future claims can be determined to be encompassed within his original creation.||”|
Whether a specification sufficiently supports a patent's claims under Section 112 is assessed through the eyes of the hypothetical "person having ordinary skill in the art," or PHOSITA. What the PHOSITA is likely to understand or find demonstrated is a reasonable proxy for what third parties are likely to perceive.
- ↑ Vas-Cath Inc. v. Mahurkar, 935 F.2d 1555, 1561, 19 U.S.P.Q.2d (BNA) 1111 (Fed. Cir. 1991) (full-text) (quoting Rengo Co. v. Molins Mach. Co., 657 F.2d 535, 551, 211 U.S.P.Q. (BNA) 303 (3d Cir.) (full-text), cert. denied, 454 U.S. 1055 (1981)). The court noted that another rationale, to give public notice of a patent's scope, may have had greater bearing previously, before the patent statutes required that applications contain separately identified claims. 935 F.2d at 1560-61.
See also Edit
External resource Edit
- MPEP 2163: Guidelines for the Examination of Patent Applications Under the 35 U.S.C. 112(a) or Pre-AIA 35 U.S.C. 112, para. 1, “Written Description” Requirement.