Expert testimony needed on patent indefiniteness claims

Description

Abstract: When a district court finds that expert evidence is unnecessary to supporting a patent invalidity argument, most plaintiffs would probably think they’re off the hook. But this article examines a case in which an appeals court found that expert testimony was indeed necessary for determining infringement liability. The court’s ruling is a strong reminder that attorney argument won’t suffice when evidence is necessary. As the court noted, it can’t be assumed that, without evidence, a general purpose judge can ascertain the view of experts in the field. Elcommerce.com v. SAP AG, 2011-1369, Feb. 24, 2014 (Fed. Cir.)