In an August 18 memorandum1 , the U.S. Patent and Trademark Office (USPTO) issued binding agency guidance on the proper role of "applicant admitted prior art" (AAPA) in inter partes review (IPR) proceedings. The memorandum clarified that AAPA, which generally consists of the applicant's statements in a challenged patent, cannot serve as the sole reference in an invalidity ground because AAPA is not a "prior art patent or printed publication" under 35 U.S.C. § 311(b). AAPA may, however, be used to show "general knowledge" in the art at the time of the invention if it is asserted in combination with other, qualified prior art.

According to the memorandum, Patent Trial and Appeal Board (PTAB) panels have been inconsistent in deciding whether § 311(b)—which allows requests for IPR "only on the basis of prior art consisting of patents or printed publications"—allows the use of AAPA. Panels have generally interpreted the statute in three ways: (1) AAPA is technically a "prior art patent" and thus can be relied on, alone or in a combination, as a basis for IPR; (2) AAPA is neither a prior art patent nor a printed publication and thus cannot be relied on, whether alone or in a combination, as a basis for IPR; or (3) AAPA is neither a prior art patent nor a printed publication and thus cannot be relied on alone as a basis for IPR, but it may be combined with other prior art to demonstrate obviousness.  The memorandum requires the PTAB to apply this third interpretation.

In coming to this conclusion, the Patent Office explained that § 311(b) plainly requires a "basis" that is either a "prior art patent" or a "printed publication." And because neither the challenged patent nor statements therein are a "prior art patent," AAPA cannot form the necessary "basis" under § 311(b). As a result, AAPA cannot be used for anticipation or single-reference obviousness grounds because such grounds would lack an appropriate "basis."

The memorandum clarifies, however, that AAPA may be used in conjunction with prior art that does qualify as a "basis" under § 311(b). In particular, AAPA can be used to show "general knowledge" in the art, which can in turn be used in an obviousness challenge. For example, AAPA can demonstrate "motivation to combine" or can supply a "missing limitation" in an obviousness combination. Of course, as with other evidence of general knowledge, the patent owner is free to challenge whether AAPA indeed demonstrates what the petitioner alleges.

The Patent Office further explained that using AAPA to show "general knowledge" does not run afoul of § 311(b) because other prior art serves as a "basis" (or "starting point") for the petition. Indeed, it has been "longstanding practice" in reexamination proceedings—which are governed by a "materially-identical" statute to § 311(b)—to allow AAPA as evidence of general knowledge. The memorandum further notes that other statutes, such as those allowing expert declarations in IPRs, similarly allow "evidence outside a prior art patent or printed publication."

In a final note, the Patent Office addressed an apparent inconsistency between its guidance and 37 C.F.R. § 42.104(b)(4), which asks petitioners to "specify where each element of the claim is found in the prior art patents or printed publications relied upon." The memorandum explained that this regulation "requires specific information from the parties to ensure orderly proceedings, but does not narrow the scope of IPR petitions further than § 311 itself does," citing other C.F.R. regulations that the PTAB does not strictly enforce.

Practice Tip:

In addition to clearing up some uncertainty in IPRs, the Patent Office may have provided a useful tool for petitioners by expressly allowing AAPA to supply missing limitations and reasons to combine in obviousness challenges. If used in this way, petitioners should be sure to characterize AAPA as "general knowledge" and use it in conjunction with a prior art patent or printed publication.

By that same token, patentees should be on the lookout for petitions that fail to properly characterize alleged AAPA as "general knowledge" or that fail to assert AAPA in conjunction with other art. Patentees should also keep in mind that AAPA can be challenged as failing to show the "general knowledge" alleged by the petitioner. Finally, patentees should be cautious regarding what subject matter they acknowledge as prior art or "background."


1 Memorandum from Andrei Iancu, Under Secretary and Director, U.S. Patent and Trademark Office, to Members of the Patent Trial and Appeal Board (Aug. 18, 2020) (on file with the U.S. Patent and Trademark Office).

Originally published by Akin Gump, August 2020

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