Discovery of Claim Construction and Infringement Analysis May be Compelled Prior to a Markman Hearing

A defendant in a patent infringement suit may, during discovery and prior to a Markman hearing, compel the plaintiff to produce claim charts, claim constructions, and element-by-element infringement analyses. S.S. White Burs, Inc. v. Neo-Flo, Inc., No. 02-3656 (E.D. Pa. May 2, 2003). The court recognized that some of the material requested might be privileged and that such material should be listed in a privilege log and not disclosed, but concluded that “[c]laim interpretations are not protected by the attorney client privilege, nor are they attorney work product, since Plaintiffs will have to disclose them to prove their case.” Additionally, the court required the plaintiffs to identify non-privileged material on which their claim construction relied, “such as other patents, Patent Office decisions, technical literature, or the like.” Although the court indicated that the plaintiffs were correct in their assertion that the defendants had no basis for demanding production of information in a specific form, such as a claim chart, the court ordered the plaintiffs to produce such a chart “because this is a clear and frequently-used means for comparing patent claims.”