USPTO Issues Guidance on the Treatment of Applicant Admitted Prior Art During Inter Partes Review

On August 18, 2020, the U.S. Patent Office published a guidance memorandum regarding the treatment of applicant statements in a patent challenged in an IPR (“applicant admitted prior art” or “AAPA”). The PTO observed that different Board panels had reached inconsistent interpretations as to whether and how 35 U.S.C. § 311(b) limits an IPR petitioner's reliance on those statements.

35 U.S.C. § 311(b) provides that an IPR challenge may be based “only on the basis of prior art consisting of patents or printed publications.” Noting that a “patent cannot be prior art to itself,” the PTO explained that applicant statements in the challenged patent do not qualify as a patent or printed publication and therefore are not prior art under § 311(b). However, it stated that AAPA does fall into the category of evidence the Board may consider for more limited purposes, such as providing evidence of the general knowledge possessed by someone of ordinary skill in the art or to support a motivation to combine.

The PTO instructed Board panels to examine whether the petitioner uses the specification statements, in conjunction with at least one prior-art patent or publication, as evidence of the general knowledge of a person of ordinary skill in the art. The PTO further clarified that the intent of § 311(b) is not to foreclose considering pertinent evidence of patentability, but to ensure that at least one prior-art patent or publication forms the basis of the IPR. This interpretation, as asserted by the PTO, is consistent with other AIA provisions, including 35 U.S.C. §§ 312, 314, and 316.

Accordingly, petitioners may use AAPA to evidence the level of skill in the art and to support arguments regarding the motivation to combine prior art references. In some circumstances, petitioners may also rely on AAPA to establish that a missing claim limitation was generally known in the art before the challenged patent’s filing date. As with other types of supporting evidence, patentees are free to challenge the accuracy of a petitioner’s characterization of the AAPA, and the Board retains discretion to assess whether the AAPA constitutes evidence of general knowledge of the art.

Although it remains to be seen whether application of this guidance is reviewable by the Federal Circuit—and if so, whether the Federal Circuit will agree with the PTO’s interpretation of § 311(b)—the guidance is binding on the Board for the time being.