In early February 2023, the Patent Office’s Director designated as precedential the Patent Trial and Appeal Board’s decision in Xerox Corp. v. Bytemark, Inc., IPR2022-00624, Paper 9 (PTAB Aug. 24, 2022). In this decision, the Board denied a petition seeking inter partes review. The petitioner asserted the challenged patent claims were obvious over printed publication prior art. One of the claimed features was not asserted to be disclosed in the published prior art, but rather asserted to be part of an ordinarily skilled artisan’s common knowledge. The Board characterized this as a “conclusory assertion,” and gave little weight to the accompanying expert witness’s declaration cited in support. Why? Because the declaration, according to the Board, “merely repeats, verbatim, the conclusory assertion for which it is offered to support,” and “does not cite to any additional supporting evidence or provide any technical reasoning [in] support.” Id. at 15.

The Board further explained that such a declaration “is particularly problematic in cases where, like here, expert testimony is offered not simply to provide a motivation to combine prior-art teachings, but rather to supply a limitation missing from the prior art.” Id. at 16. Such a declaration is entitled to weight where the missing limitation is “unusually simple and the technology particularly straightforward,” but the petitioner neither alleged that nor offered support for such an allegation. Id.

This is not a controversial decision. After all, the Board’s rules caution that such a declaration may be given little or no weight. See 37 C.F.R. § 42.65(a) (“Expert testimony that does not disclose the underlying facts or data on which the opinion is based is entitled to little or no weight.”). And Federal Circuit decisions have also explained this potential. See Upjohn Co. v. Mova Pharm. Corp., 225 F.3d 1306, 1311 (Fed. Cir. 2000) (“Lack of factual support for expert opinion to factual determinations, however, may render the testimony of little probative value in a validity determination.”) (quoting Ashland Oil, Inc. v. Delta Resins & Refractories, Inc., 776 F.2d 281, 294 (Fed. Cir. 1985)); Carella v. Starlight Archery & Pro Line Co., 804 F.2d 135, 138 (Fed. Cir. 1986) (“Although in some circumstances unsupported oral testimony can be sufficient to provide prior knowledge or use, it must be regarded with suspicion and subjected to close scrutiny.”). The Board’s decision cites this authority.

Dozens of Board decisions have been designated as precedential and can be found at this link. These decisions establish additional binding authority on practice and procedure involving cases the Board decides. Typically, these decisions address important issues regarding case law or issues of broad applicability to the Board. Most petitions for inter partes review and post-grant review are accompanied by expert declarations. The Xerox decision may merely be the Director’s reminder that the Board has discretion to accord those declarations little weight where they are not themselves supported by evidence or technical reasoning.