On August 11, 2023, the Federal Circuit laid out the permissible scope of a petitioner’s reply in IPR.
Before the court was an appeal of PTAB’s findings of unpatentability, on remand, in IPR2016-01502 re U.S. Patent No. 6,548,019. Rembrandt Diagnostics, LP v. Alere, Inc., Case No. 2021-1796 (Fed. Cir. Aug. 11, 2023). In the initial inter partes review proceeding, the Board instituted only on certain grounds and declined to review two claims. Federal Circuit remanded for the Board to consider all the challenged claims and grounds. On remand, the Board found all remaining claims at issue unpatentable for obviousness. Patent owner Rembrandt appealed, arguing the Board abused its discretion when it relied on new theories Petitioner Alere raised in its reply. Rembrandt at 5-8.
The Federal Circuit found no such new theories because Alere’s reply arguments involve “the same ‘legal ground’ based on ‘the same prior art reference[s]’ and the ‘same legal argument.’” Rembrandt at 14.
The court provided examples of a reply containing a new theory on unpatentability: when the petition asserts a single reference and the reply argues a motivation to combine references, Rembrandt at 10 (citing Intelligent Bio-Sys., Inc. v. Illumina Cambridge Ltd., 821 F.3d 1359, 1369 (Fed. Cir. 2016)), or when the reply switches theories and asserts previously unidentified prior-art disclosures, id. at 11 (citing Ariosa Diagnostics v. Verinata Health, Inc., 805 F.3d 1359, 1367 (Fed. Cir. 2015)).
The court also provided examples of a reply that is proper in scope: when the reply is “responsive and simply expands on previously raised arguments,” Rembrandt at 11 (citing Ericsson Inc. v. Intell. Ventures I LLC, 901 F.3d 1374, 1381 (Fed. Cir. 2018)), or when the reply further explains its legal argument, id. at 11-12 (citing Apple Inc. v. Andrea Electronics Corp., 949 F.3d 697, 706 (Fed. Cir. 2020)). The court also cautioned the Board against “pars[ing] ‘arguments on reply with too fine of a filter.’” Id. at 11 (citing Ericsson, 901 F.3d at 1380; Chamberlain Grp., Inc. v. One World Techs., Inc., 944 F.3d 919, 925 (Fed. Cir. 2019); Belden Inc. v. Berk-Tek LLC, 805 F.3d 1064, 1081–82 (Fed. Cir. 2015)).