The timing considerations that go into filing a petition for inter partes review with the PTAB have become progressively more difficult to navigate as the PTAB exercises increased discretion in rejecting IPRs. This trend started with the precedential NHK decision in which the PTAB rejected an IPR petition on the basis of an upcoming district court trial. Since then, the Federal Circuit has continued to provide the PTAB with increased autonomy by expanding its discretion to institute IPR under 314(a).
Likewise, in the Thryv decision the Supreme Court all but cut off any review of institution by the Federal Circuit, and in the SAS decision, the Supreme Court determined that all PTAB decisions on whether to institute IPR have to be binary, either instituting on all grounds or denying IPR altogether. Following SAS, the PTAB also started to deny institution of IPR where there is a reasonable likelihood that the petitioner will prevail on only a minority of the proposed grounds for unpatentability. For example, in Biofrontera v. DUSA Pharms the PTAB exercised its discretion to deny institution where the petitioner only showed a reasonable likelihood of success on only 1 of 8 grounds.
Since the NHK decision, many patent owners have raised NHK in an attempt to thwart institution of IPR as redundant to invalidity defenses raised in district court proceedings. Approximately 33 patent owner preliminary responses have raised NHK in similar circumstances since December 2018, with 20 of those cases being decided in Jan to May of 2020 alone. Below is a chart detailing the 10 cases where IPR institution has been denied on the basis of an NHI argument, consolidated into a single entry where multiple IPR denials related to the same parallel district court case.
Table 1: IPR denied based on NHK
| Decision Date | Case Name* | Materially different prior-art arguments raised in the IPR petition(s)? | Months until district court trial after the IPR institution decision** |
| 12/3/2018 | Mylan v. Bylar | No | 4 |
| 10/16/2019 | Next caller v. Trustid | No | 9 |
| 1/22/2020 | Magellan v. Sunoco | No | 2 |
| 3/10/2020 | Bentley v. Jaguar | Yes | 7 |
| 3/26/2020 | Ford v. MIT | No | 0 (finished, under appeal) |
| 3/27/2020 | Google v. UNILOC | No | 5 |
| 5/13/2020 | Apple v. FINTIV | No | 10 |
| 5/15/2020 | Cisco v. Ramot at Tel Aviv | No | 6 |
| 5/19/2020 | Intel v. VLSI | No | 5-7, estimated |
The most recent of these cases is perhaps one of the most favorable to the patent owner. In a series of decisions captioned Intel v. VLSI, the PTAB relied on NHK to deny review under 314(a) even though the District court has suspended its trial schedule due to Covid-19. Significantly, petitioner Intel filed its IPR petitions fully three months prior to the one-year statutory deadline after service of the district court complaint. Acknowledging these facts, the PTAB focused on the significant investment that had already gone into the parallel district court case, with fact discovery scheduled to end in May. Additionally, the trial date was set for October 2020, with a final written decision from the PTAB likely not to come until May 2021 if IPR were instituted. Even with the district court currently closed due to Covid-19, the PTAB found that it is likely the district court will go to trial before a final decision is reached. In weighing all the factors set forth in NHK, the PTAB ultimately decided that the likelihood of a district court trial in 5 to 7 months warranted denial of review.
The cases identified above are just the first in a series of PTAB developments favoring patent owners. With the ever-evolving landscape of IPR litigation it has become even more important than ever that parties looking to petition for IPR have capable and knowledgeable counsel who are able to navigate the unwritten rules of discretionary denial of IPRs.