Last week, Microsoft got tripped up at oral argument on the blocking and tackling of IPR practice: making sure your prior art is prior art.

The specific error was eminently avoidable, though perhaps also eminently understandable. Under Federal Circuit law, a reference generally does not count as prior art unless it was “indexed.” (Think Dewey Decimal system, or the USPTO’s classification system). To clear this “indexing” hurdle, Microsoft found a document that helpfully titled itself an “index” and linked to the reference-in-question. A good start, no doubt, but it turns out the document had padded its resume: it was more “list” than “index.” And, under Federal Circuit law, a “list” may not be good enough.

This List Wants You to Believe It Is an Index

The patent owner, Uniloc, sagely caught the error, citing Samsung Elecs. Co. v. Infobridge Pte. Ltd., 929 F.3d 1363 (Fed. Cir. 2019) for the relevant point of law.

When a reference is uploaded to a website or deposited in a library, the fact that the reference is indexed or cataloged in some way can indicate that it is publicly accessible. In Acceleration Bay, for example, the reference at issue was uploaded to a university website. 908 F.3d at 773. While this made the work technically accessible—someone could theoretically find it on the Internet—we explained that “public accessibility requires more than technical accessibility.” Id. (internal quotation marks omitted). And while the website indexed references “by author and year,” we agreed with the Board that this did not mean the reference at issue had been “meaningfully indexed such that an interested artisan exercising reasonable diligence would have found it.” Id. at 774; see also SRI, 511 F.3d at 1196 (“[T]he FTP server did not contain an index or catalogue or other tools for customary and meaningful research.”). On this record, we affirmed the Board’s finding that the reference was not publicly accessible even though it had been uploaded to a website.

Id. at 1369 (emphasis added). In other words, you need an index—not a list. This makes sense when you consider that public accessibility law is based on cases from the 1980’s dealing with PhD theses that were physically printed and shelved in library stacks. If not for the Dewey Decimal system, how could anything be found?

At the oral hearing, Microsoft added a new wrinkle to its argument, submitting that a skilled artisan would have plodded unguided through the whole of the 20-page list because the artisan would already have been familiar with a reference that was located on the same website as both the list and the reference-in-question.

The PTAB panel seemed unimpressed with Microsoft’s argument, as Administrative Patent Judge Jameson Lee pointedly noted: “I mean, you’re just making it up right now. That story wasn’t in your petition.”

Moral of the story: when you’re filing an IPR petition that relies on non-patent literature, it pays to double- and triple-check that all of the technical requirements for prior art status are met. This includes having a cogent explanation for why a skilled artisan would have found the reference-in-question. These technicalities, when overlooked, are often case-dispositive and impossible to fix post-institution.

The case is IPR2019-01116.