Under 35 U.S.C. § 325(d), the PTAB “may take into account whether, and reject [a] petition or request because, the same or substantially the same prior art or arguments previously were presented to the Office.” In Microsoft Corp. v. Parallel Networks Licensing, LLC, the Board instituted an IPR even though institution was primarily based on a prior art reference that had been previously presented to the USPTO. IPR2015-00483, Paper 10 (Jul. 15, 2015).

The reference at issue had been cited in prosecution of a divisional application and listed on an IDS in an ex parte reexamination proceeding. While the Board recognized that these actions showed the reference had been “previously presented” to the Office, it nonetheless declined to deny institution “on these facts” given that § 325(d) “does not require any particular outcome.”

Specifically, the Board found the citation made in the divisional application to have “less relevance to the challenged claims” because it was presented in the context of a child application that did not ultimately “mature[] into the ’554 patent.” The Board was likewise unpersuaded that the reference being listed on a “lengthy” IDS in reexamination was sufficient to deny institution of the IPR. The reference had not been “applied against the claims” and there was “no evidence that the Examiner considered the particular disclosures” cited by the petitioner. In declining to use its discretion under § 325(d), the Board also noted that “the ex parte nature of the reexaminations differs from the adversarial nature of an inter partes review.”

As this decision shows, the fact that certain prior art was previously presented to the PTO does not guarantee that the Board will exercise its discretion under § 325(d) to deny institution based on that prior art. This is particularly true if a good argument can be made that the prior art was never applied against the claims and the examiner never actually considered the particular portions of the prior art that are relied upon in the IPR petition.