In affirming a PTAB IPR decision canceling claims for obviousness, the Federal Circuit concluded that the PTAB’s reliance on references not included in the original petition did not violate due process or the patent owner’s procedural rights under the Administrative Procedure Act (APA). Anacor Pharm., Inc. v. Iancu, 889 F.3d 1372 (Fed. Cir. 2018).

Citing Genzyme Therapeutic Products Ltd. v. Biomarin Pharmaceutical. Inc., 825 F.3d 1360, 1366 (Fed. Cir. 2016) (discussed here), the court stated that new evidence was to be expected during an IPR and was permissible under the APA provided the opposing party receives notice and an opportunity to reply. Further, the court specifically noted that “the petitioner in an inter partes review proceeding may introduce new evidence after the petition stage if the evidence is a legitimate reply to evidence introduced by the patent owner, or if it used to document the knowledge that skilled artisans would bring to bear in reading the prior art identified as producing obviousness.” Anacor, 889 F.3d at 1380-81 (citing Genzyme, 825 F.3d at 1369).

In Anacor, the challenged claims were directed to treating onychomycosis, a fungal infection, using a topical treatment of tavaborole. Onychomysis is most commonly caused by fungi known as dermatophytes, but can also be caused by a yeast, Candida albicans (C. albicans). The challenged claim addressed on appeal was directed to treating onychomysis caused by dermatophytes using tavaborole.

The PTAB’s final written decision relied on the same combination of references raised in the petition, Austin and Brehove. Neither reference expressly disclosed that the onychomycosis treated in the references was caused specifically by dermatophytes rather than C. albicans. The PTAB therefore looked to additional references to inform their decision on whether a person of ordinary skill in the art would have expected tavaborole to be effective specifically against dermatophytes.

Anacor argued that the PTAB violated due process and the procedural requirements of the APA by (1) adopting a new theory of obviousness and (2) relying on evidence that Anacor did not have an opportunity to address. The court rejected Anacor’s first argument because the PTAB’s final written decision was based on the same combination of references, Austin and Brehove, cited in the petition. The court also rejected Anacor’s second argument because it concluded that Anacor had ample notice and opportunity to address references, Segal and Martin, its petition did not cite.

Specifically, the patent owner’s response cited Segal, and the petitioner introduced Mertin in its deposition of the patent owner’s expert. The petitioner’s reply brief cited both the Mertin and Segal, and Mertin was discussed at the PTAB final hearing. Under these circumstances, the court determined that the patentee had “ample notice of and an opportunity to respond to the Segal and Mertin references, which in any event were properly offered in reply to arguments made by Anacor and for the purpose of showing the state of the art at the time of the patent application.” Anacor, 889 F.3d at 1382.

Parties to PTAB trial proceedings should be aware that the PTAB may rely on new evidence not included in the petition, as long as the parties have proper notice and an opportunity to respond, such as evidence introduced in a patent owner’s response, or evidence on which the petitioner relies in a deposition of a patent owner’s expert witness.