Beware Prosecution History in PTAB Trials

Even Preliminary Proceeding Arguments Notice the Public

It is well-established that statements made by a Patent Owner during an inter partes review (IPR) can constitute prosecution disclaimer— even in papers filed by a Patent Owner before the trial. Aylus Networks, Inc. v. Apple Inc., No. 2016-1599 (Fed. Cir. May 11, 2017)

As a reminder, prosecution disclaimer prevents a patentee that clearly and unmistakably disclaimed a certain meaning for its patent claims during prosecution from recapturing this same meaning during claim construction in a subsequent litigation. As was the case in Aylus, Patent Owners are learning that the timing of such a disclaimer, or lack of express adoption by the Patent Trial & Appeal Board (PTAB), is of no moment.More recently, in F5 Networks, Inc. v. Radware, Inc.,(CAND 2018-11-19, Order) (here) the Court considered the meaning of the term “decision function.”  In deciding the meaning of this term the Court reviewed the record of earlier concluded IPR proceedings.

In the first IPR proceeding, Radware argued in its Patent Owner Preliminary Response (POPR) that the patent at issue “provides a non-exhaustive list of data route parameters[] upon which the content router determines the decision function.” Radware also argued in the POPR that the patent “requires the selection to be based on parameters of the data routes.”

In motions for summary judgment in the N.D. Cal proceeding, F5 filed a cross-motion for summary judgment that the claims of the ’853 Patent were not infringed.  F5 took the position that Radware’s positions on the meaning of “decision function” in its POPR resulted in judicial estoppel and/or disclaimer.  For disclaimer, F5 argued that the patent owner disclaimed claim scope by arguing that the decision function required the “decision function” to be based on data route parameters.

For judicial estoppel, F5 argued that parties are estopped from adopting inconsistent positions made in administrative proceedings and argued a three factor test: (1) the party’s later position must be clearly inconsistent with its earlier position; (2) whether that party succeeded in persuading a court to accept that earlier position such that judicial acceptance would make it appear that one of the court’s was misled; and (3) the party seeking the inconsistent advantage would derive an unfair advantage if not estopped.  The Court ultimately relied on disclaimer in granting the cross-motion for summary judgment, explaining:

" In light of the position Radware took before the Board, the Court concludes that the input for “decision function” is, as a matter of law, limited to data route parameters. As with patent prosecution, statements made by the patent owner during inter partes review put the public on notice of how the patent owner views its patent. See Aylus Networks, Inc. v. Apple Inc., 856 f . 3d 1353, 1359 (Fed. Cir. 2017). Radware cannot abandon its earlier statements to broaden the reach of its patent now that it is arguing for infringement. Even if the PTAB may not have expressly adopted Radware’s interpretation, the public is still entitled to rely on it. . See Am. Piledriving Equip., Inc. v. Geoquip, Inc., 637 f . 3d 1324, 1336 (Fed. Cir. 2011) (explaining that “regardless of whether the examiner agreed with” a patent owner’s statements, those “statements still inform the proper construction of the term”).

Sometimes winning the PTAB battle may lose you the war.

Scott A. McKeown is an author of the Patents Post Grant.