Determining what the claims of a patent mean, i.e., claim construction, is largely considered the single most important issue in any patent case. It impacts virtually every claim or defense in a patent infringement lawsuit and in many instances drives disposition of a case. On Sept. 13, 2013, the Court of Appeals for the Federal Circuit sat en banc in Lighting Ballast Control LLC v. Philips Electronics North America Corporation and Universal Lighting Technologies, Inc. to address the standard of review to be applied to a district court’s claim construction ruling. This was only the fourth time in 20 years that the Federal Circuit had sat en banc to address the contours of the claim construction process. In particular, in Lighting Ballast, the Federal Circuit asked the parties to address the following questions:
- Should the Federal Circuit overrule Cybor Corp. v. FAS Techs., Inc. (in which the Federal Circuit held that “as a purely legal question, we review claim construction de novo on appeal including any alleged fact-based questions relating to claim construction”)?
- Should the Federal Circuit afford deference to any aspect of a district court’s claim construction?
- If so, which aspects should be afforded deference?
While both parties of the Lighting Ballast case agree that Cybor’s de novo standard of review should not be applied to all aspects of a district court’s claim construction ruling and thus should be modified in some way, they agree on little else. Lighting Ballast seeks complete abandonment of the de novo standard of review and argues that an appellate court should afford deference to all aspects of a district court’s claim construction ruling. Under this standard, a district court’s claim construction ruling could only be reversed if the appellate court determined the ruling was clearly erroneous.
In contrast, Universal Lighting Technologies seeks to maintain de novo review for most aspects of a district court’s claim construction ruling and afford deference to “disputed issues of historical fact.” Thus, under Universal Lighting Technologies’ proposal, an appellate court should afford deference to a district court’s determination that a word or phrase had specialized meaning in a field of art at the time of invention and to what that specialized meaning was at the time.
While it is possible that the Federal Circuit could leave Cybor’s de novo standard of review undisturbed, that appears unlikely. First, both parties, as well as a majority of amici curiae, including the United States Patent and Trademark Office and the Honorable Paul Michel, former chief judge of the Federal Circuit, have argued for some departure from that standard.
Second, the very fact that the Federal Circuit heard the case en banc signals a certain level of dissatisfaction with the de novo standard, which many have pointed to as the cause of high reversal rates of district court’s claim construction rulings by the Federal Circuit.
But the potential impact of the Lighting Ballast decision on future patent litigation remains uncertain. Any potential impact largely rests on how much deference, if any, the Federal Circuit decides to afford to a district court’s claim construction ruling and how to develop a standard that is workable at the district court level. The difficulty the Federal Circuit faces is finding the proper balance between issues of fact that would be subject to a deferential standard and issues of law that would remain under the de novo standard. Regardless of the ultimate fact-law demarcation settled on by the Federal Circuit, any change in the standard will force both inside and outside counsel to rethink at least overall litigation budgets, pre-suit investigations, settlement strategy, summary judgment strategy, and the role of experts in the claim construction process.