Narrowing the Disclaimer Doctrine: Federal Circuit Cabins the Reach of Disclaimers in the IPR Context | Haug Partners LLP


The United States Court of Appeals for the Federal Circuit recently affirmed three Inter Partes Review (IPR) final written decisions of the U.S. Patent Trial and Appeal Board (“the Board”) where the Board concluded that petitioner, Trend Micro. Inc. (“Trend”), had shown the challenged patent claims in patentee, Cupp Computing AS’s (“Cupp”), U.S. Patents Nos. 8,631,488 (“’488 patent”), 9,106,683 (“’683 patent”), and 9,843,595 (“’595 patent”), unpatentable as obvious over two prior art references.1 Setting a new precedent with respect to claim construction, the Federal Circuit held that although a patentee’s clear and unmistakable disavowals of claim scope during an IPR proceeding can narrow the scope of the claims, such a statement serves to narrow the claims only in subsequent proceedings—not in the IPR proceeding during which the statement is made.2

Cupp contended that the PTAB erred when it rejected Cupp’s disclaimers in the IPR.3 The Board did not find this argument persuasive and concluded that it could ignore the patentee’s disavowal in construing the claims.4 The Federal Circuit agreed with the Board.5

I. Introduction

Each of the three patents at issue share a common name and priority date and address the problem of malicious attacks aimed at mobile devices.6 The patents concern methods for waking a mobile device from a power-saving mode and then performing security operations on the device, “such as scanning a storage medium for malware, or updating security applications.”7

The issue on appeal to the Board’s determination related to the precedential decision is one of claim construction.8 Specifically, each independent claim in the three patents includes the limitation “the mobile device having a mobile device processor different than the mobile security system processor.”9

II. Background

In March 2019 Trend petitioned the Board for an IPR of several claims in each of the ’488, ’683, and ’595 patents arguing that the claims were unpatentable as obvious.10 Trend presented two pieces of prior art contending that either could be individually relied upon to show the challenged claims would have been…