On August 18, 2020, the USPTO issued guidance regarding the reliance on Applicant Admitted prior art (AAPA).  Under 35 U.S.C. § 311(b), IPRs may be instituted only “on the basis of prior art consisting of patents or printed publications.”  The guidance clarifies that statements in the specification of the patent being challenged are not prior art patents or printed publications, and thus cannot form the basis of an IPR.  Rather, AAPA can only be used as evidence that the PTAB can consider solely for limited purposes in particular circumstances.