[IPR] Standard - Preponderance of the evidence (different from the clear and convincing standard in district courts)

35 U.S.C. 316 (e) states that the PTAB determined that a petitioner in an inter partes review proves unpatentability by a preponderance of the evidence (, which is different from the standard used in the district courts).

What's the impact of this difference? In Novartis AG v. Noven Pharm. Inc., 853 F.3d 1289 (Fed. Cir., 2017), the Federal Circuit disagreed with the patent owner's arguments that its patent should not be invalidated by the PTAB because the same patent was not invalidated by the district court.

The Federal Circuit cited the Supreme Court's Cuozzo Speed Techs., LLC v. Lee, ___ U.S. ___, 136 S.Ct. 2131, 2146, 195 L.Ed.2d 423 (2016):

[a] district court may find a patent claim to be valid, and the [USPTO] may later cancel that claim in its own review.... This possibility, however, has long been present in our patent system, which provides different tracks — one in the [USPTO] and one in the courts — for the review and adjudication of patent claims. As we have explained ..., inter partes review imposes a different burden of proof on the challenger. These different evidentiary burdens mean that the possibility of inconsistent results is inherent to Congress'[s] regulatory design.

Then, the Federal Circuit held that the prior decisions were not controlling on the PTAB.