In Acceleration Bay, LLC v. Activision Blizzard Inc. et al., Nos. 2017-2084, 2085, 2095, 2096, 2097, 2098, 2099, 2117, 2118 (Nov. 6, 2018), the Federal Circuit affirmed the Patent Trial and Appeal Board’s (PTAB) final written decision in a group of related proceedings, including IPR2015-01951.[1] The PTAB had found that several claims of the challenged patents were unpatentable and that other claims, along with substitute claims of the challenged patents, were not unpatentable. Particularly, the PTAB found that one of the references used to challenge the different patents was not a printed publication under 35 U.S.C. § 102(a). The Federal Circuit affirmed the PTAB’s decision with respect to the printed publication issue and held that the reference was not a printed publication under § 102(a).


Acceleration owns U.S. Patent Nos. 6,829,634 (the ’634 patent), 6,701,344 (the ’344 patent), and 6,714,966 (the ’966 patent). Blizzard filed six petitions for inter partes review (IPR)—two for the ’634 patent, two for the ’344 patent, and two for the ’966 patent—based primarily on two primary references: (1) an article by Peter J. Shoubridge et al.[2] (the Shoubridge article); and (2) an article by Meng-Jang Lin et al.[3] (the Lin article). The PTAB instituted each IPR and rendered six final written decisions. The PTAB concluded that the Lin article was not a printed publication under 35 U.S.C. § 102(a) and thus, in the IPRs based on the Lin article, the PTAB determined that Blizzard failed to show that the challenged claims are unpatentable over the Lin article. Blizzard appealed the PTAB’s holding that the Lin article is not a printed publication under § 102(a).

Blizzard proffered testimony of Glen Little, a Systems Administrator at the Computer Science and Engineering (CSE) department of the University of California, San Diego. Acceleration Bay at 11. According to Little’s testimony, the Lin article was uploaded to the CSE Technical Reports Library’s website. Id. at 11-12. Little stated that when an article is uploaded to the website, “a staff member [in the CSE department] assigns a unique identifier to each [article] based on the year it was uploaded.” Id. at 12. The PTAB stated that for an article to be considered “publicly accessible,” more is required than technical accessibility. Id.

The PTAB determined that the Lin article was not publicly accessible because it was not disseminated to the public in a manner that would allow an interested, skilled artisan, using reasonable diligence to have found the Lin article on the CSE Technical Reports Library website. See id. at 12-13. The website allowed a user to view a list of technical reports indexed only by author or year, but the user could not determine how many articles were in the database. See id. at 12. The PTAB determined that a skilled artisan might have discovered the Lin article, but only by “skimming through potentially hundreds of titles in the same year, with most containing unrelated subject matter, or by viewing all titles in the database listed by author, when the authors were not particularly well known.” Id. Additionally, the PTAB determined that the website’s advanced search form was deficient because the functionality was not reliable. Id. Glen Little stated that the CSE department did not verify the functionality of the website’s advanced search capability when a new article was uploaded. Id. at 13. He also stated that it was possible that the search function did not work. Id.


On appeal, Blizzard argued that the PTAB erroneously concluded that the Lin article was not a printed publication under § 102(a). Id. at 10. The Federal Circuit stated that whether a reference qualifies as a printed publication depends on whether the reference is publicly accessible. Id. at 11. According to the Federal Circuit, “‘public accessibility’ has been called the touchstone in determining whether a reference constitutes a ‘printed publication.’” Id. (quoting In re Hall, 781 F.2d 897, 898–99 (Fed. Cir. 1986)). A reference is considered publicly accessible if it was “‘disseminated or otherwise made available to the extent that persons interested and ordinarily skilled in the subject matter or art, exercising reasonable diligence, can locate it.’” Id. (emphasis added) (citing In re Wyer, 665 F.2d 221, 226 (CCPA 1981)).

The Federal Circuit held that the PTAB did not err in finding that the Lin article was not a printed publication. Id. at 13. The Court indicated that some of the most important evidence supporting this conclusion was the fact that the Lin article was not indexed in a meaningful way, and that the CSE Technical Reports Library website included a deficient advanced search form. See id. Blizzard argued that the Federal Circuit does not need to consider the website’s search functionality because the Lin article “was indexed by title for a given year, author name, and unique sequence number, which is sufficient for public accessibility under In re Hall.” Id. at 14. The Federal Circuit disagreed.

The Court stated that the test for public accessibility “is not ‘has the reference been indexed?’” Id. Instead, where indexing is at issue, the Court indicated that the article must be meaningfully indexed, i.e., the article must be “‘available to the extent that persons interested and ordinarily skilled in the subject matter or art, exercising reasonable diligence, can locate it.’” Id. (quoting Voter Verified, Inc. v. Premier Election Sols., Inc., 698 F.3d 1374, 1380?81 (Fed. Cir. 2012)). The Federal Circuit stated that the PTAB’s findings were supported by substantial evidence, and the Court agreed that the Lin article was not a printed publication under § 102(a).


This case provides guidance to practitioners who are analyzing prior art references when preparing a petition for IPR. When analyzing such references, practitioners should consider the potential evidentiary challenges against an electronically-indexed article. The Federal Circuit has outlined that a website’s search functionality should be taken into account when determining public accessibility, particularly when the search functionality may be less than comprehensive. As such, the Court has stated that in certain situations, an article that is indexed and accessible may not qualify as a printed publication under 35 U.S.C. § 102(a).