IP Newsflash

A judge in the District of Delaware has ruled that estoppel under 35 U.S.C. § 315(e)(2) does not apply to prior-art products, even if those products are “cumulative” of prior-art patents or printed publications that were raised during IPR proceedings. As such, the court denied a patentee’s motion for summary judgment that sought to estop the defendant from pursuing anticipation and obviousness positions that were premised on prior-art products.

The Federal Circuit recently clarified that the scope of IPR estoppel in district courts includes prior art grounds that were raised or reasonably could have been raised in a petition for inter partes review (IPR), reversing its prior decision in Shaw Industries Group, Inc. v. Automated Creel Systems, Inc., 817 F.3d 1293 (Fed. Cir. 2016). The court’s decision resolved a split in district courts over whether estoppel extends to grounds that were omitted from a petition for IPR.

The Eastern District of Texas has rejected a plaintiff’s argument that if a patent owner concedes in an inter partes review (IPR) that a prior art reference discloses all elements of a patent claim, the reference necessarily subsumes all other prior art disclosing those elements. In the IPR preceding the court’s decision, patent owner conceded the disclosure in a printed prior art reference of all the elements of the challenged independent claims. In the district court, plaintiff filed a motion for partial summary judgment of validity on grounds of IPR estoppel, asserting that any prior art system that disclosed the conceded claim elements (in the IPR) is subsumed in the printed prior art reference and estopped under 35 U.S.C. § 315(e)(2). The court denied plaintiff’s motion as an attempt to impermissibly expand the scope of estoppel.

During a Markman hearing, a judge in the Eastern District of North Carolina denied a plaintiff’s request that the defendant be judicially estopped from arguing claim constructions that were different from positions the defendant took in inter partes review (IPR) proceedings before the Patent Trial and Appeal Board (PTAB).

Inter partes review (IPR) proceedings can give rise to statutory and collateral estoppel. But these two bases for estoppel attach at different times, which can lead to asymmetrical outcomes in related district court proceedings. One such situation arose in a recent pre-trial ruling in the District of Delaware, where a plaintiff was permitted to continue asserting patent claims that were found unpatentable in an IPR while the defendant was prevented from asserting prior art to defend itself at trial.