Estoppel Doctrine in China's Patent System
In a precedential opinion entered on May 7, 2025, the United States Court of Appeals for the Federal Circuit affirmed a jury verdict invalidating claims of two patents for anticipation and obviousness over the prior art....more
The Federal Circuit recently resolved a split among the district courts whether patent infringement defendants who bring inter partes review (IPR) challenges are estopped from raising new prior art challenges in a co-pending...more
Recently, an ITC Administrative Law Judge applied IPR statutory estoppel under 35 U.S.C. § 315(e)(2) in denying a Respondent’s motion for summary determination of invalidity in Certain Audio Players and Components Thereof,...more
In IOENGINE, LLC v. Ingenico Inc. (Fed. Cir. 2025), the Federal Circuit narrowed the scope of IPR estoppel under 35 U.S.C. § 315(e)(2), which precludes an IPR petitioner from asserting in court that a patent claim “is invalid...more
In a significant development for patent litigants, the Federal Circuit in Ingenico Inc. v. IOENGINE, LLC, affirmed an important limitation on the scope of IPR estoppel under 35 U.S.C. § 315(e)(2). Specifically, the court held...more
On May 7, 2025, the U.S. Court of Appeals for the Federal Circuit (“CAFC”) affirmed a decision by the U.S. District Court for the District of Delaware (“district court”) that found claims of two IOENGINE, LLC (“IOENGINE”)...more
Estoppel certification in reexamination prevents relitigation of resolved issues....more
This Federal Circuit Opinion analyzes statutory estoppel under 35 U.S.C. § 315(e)(1) and examines offensive and defensive arguments related to § 103 obviousness. Gesture Technology Partners, LLC is the owner of U.S....more
Ex parte reexamination (EPRx) comes with risks and rewards for both patent challengers and patent owners. Patent challengers enjoy a lower threshold for institution and avoid the estoppel risk of other post-grant proceedings...more
In Kroy IP Holdings, LLC v. Groupon, Inc., 127 F.4th 1376 (Fed. Cir. 2025), the Federal Circuit held that patentees in district court are not collaterally estopped from asserting claims that were not immaterially different...more
In response to a lawsuit for patent infringement, often a defendant will file an inter partes review (IPR) challenging the validity of the asserted claims. How can a patentee avoid this scenario?...more
On October 25, 2024, the United States District Court for the Eastern District of Pennsylvania ordered Comcast Corporation (“Comcast”) to identify the date on which it learned of each patent, patent application, and printed...more
Amongst the many decisions an attorney makes throughout litigation, there is one choice that can shape the outcome of a case way before filing a motion, setting discovery and trial strategy, or even calling a witness: venue,...more
In 2016, the Federal Circuit expressed doubt that claim constructions from the PTAB could give rise to estoppel in later litigation because “the [PTAB] applies the broadest reasonable construction of the claims while the...more
The Federal Circuit recently issued a decision in SoftView LLC v. Apple Inc. clarifying the scope of patent owner estoppel set forth in 37 C.F.R. § 42.73(d)(3)(i). 2024 WL 3543902 (Fed. Cir. July 26, 2024). The regulation...more
On July 26, 2024, the Court of Appeals for the Federal Circuit (“CAFC”) issued a precedential opinion reversing-in-part decisions from the U.S. Patent Trial and Appeal Board (“PTAB”) in two inter partes reexamination...more
On July 26, 2024, in a precedential decision, the U.S. Court of Appeals for the Federal Circuit (CAFC) upheld and expounded on the estoppel provision set forth in 37 C.F.R. § 42.73(d)(3)(i). The CAFC confirmed that the Patent...more
Precedential and Key Federal Circuit Opinions - 1. BACKERTOP LICENSING LLC [OPINION] (23-2367, 23-2368, 24-1016, 24-1017 Prost, Hughes, and Stoll) - Hughes, J. The Court affirmed the District Court’s orders (1)...more
Recently, District Court Judge Thomas S. Zilly in the Western District of Washington granted Ironburg Inventions Ltd.’s (“Ironburg”) motion for inter partes review (“IPR”) estoppelpursuant to 35 U.S.C. § 315(e)(2), which...more
We previously reported on the litigation brought by ModernaTX, Inc. and Moderna US, Inc. (collectively, “Moderna”) against BioNTech SE, BioNTech Manufacturing GmbH, BioNTech US Inc. (collectively, “BioNTech”), and Pfizer Inc....more
Addressing an issue of first impression, the US Court of Appeals for the Second Circuit concluded that two medications that contain the same ingredients but are packaged in different forms constitute separate markets for...more
As any PTAB practitioner knows, the possibility of being estopped from asserting prior art in district court is a significant risk that must be considered when filing an IPR. Section 315(e)(2) prevents a petitioner, following...more
A review of 2023 reveals it was an active and impactful year in shaping the policy and practice before the Patent Trial and Appeal Board (PTAB or Board) at the U.S. Patent and Trademark Office (USPTO). In fact, all three...more
In GeigTech East Bay v. Lutron Electronics, patent owner GeigTech argued that Lutron should be estopped under 35 U.S.C. § 325(e)(2) from asserting two prior art grounds that it said Lutron could have reasonably raised in its...more
2023 was a busy year at the Patent Trial and Appeal Board, as post-grant practice continued to evolve at a rapid pace. At the United States Patent and Trademark Office, there were big developments in Director Review and...more