In inter partes review (IPR) proceedings, petitioners bear the burden of demonstrating that documents relied on as printed publications were publicly accessible before the effective filing date of a challenged patent. In Pfizer, Inc. v. Biogen, Inc., IPR2017-01166, Paper 9 at 10 (PTAB Nov. 13, 2017), the PTAB found that Pfizer failed to establish the public accessibility of a Rituxan® drug label relied on in a prior art challenge.
In its petition, Pfizer submitted prior art challenges based on the Rituxan® drug label and asserted that the label constituted a printed publication. The Board denied institution of the IPR. In the decision denying institution, the Board found that Pfizer’s evidence did not establish that “the Rituxan label was disseminated or otherwise made available to ordinarily skilled artisans exercising reasonable diligence prior to the critical date for the `172 patent.”