What constitutes an admission as prior art in patent law?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

An admission as prior art in patent law occurs when an applicant identifies the work of another as “prior art” in the specification or during prosecution. According to MPEP 2129, such admissions “can be relied upon for both anticipation and obviousness determinations, regardless of whether the admitted prior art would otherwise qualify as prior art under the statutory categories of 35 U.S.C. 102.”

It’s important to note that even if labeled as “prior art,” an inventor’s own work may not be considered prior art against their claims unless it falls under one of the statutory categories.