CLAIM CONSTRUCTION ERRORS

MADE BY DISTRICT COURTS IN 2002-03

Claim construction is one of the most complex and important components of patent litigation.This is why district courts and lawyers frequently devote significant resources and time to conducting a Markman hearing. Unfortunately, all too frequently these efforts seem wasted when the claim construction is corrected on appeal by the United States Court of Appeals for the Federal Circuit.In fact, based on a review of published claim construction cases from September 2002 through June 2003, these authors determined that the Federal Circuit corrected the district court’s claim construction in 29 out of 39 cases.This accounts for an “error rate” of about 74 percent.

This Article focuses exclusively on the 29 published cases in which the Federal Circuit modified the construction of the district court. Of these 29 cases, the Federal Circuit found that the district courts construed the claims too narrowly in 22 of the cases, too broadly in five of the cases, and construed some claims too narrowly and other claims too broadly in two of the cases.Finally, the Federal Circuit reversed or vacated the district courts’ rulings in 25 of the 29 cases involving some type of modification.

B.Federal Circuit Broadened the District Court’s Claim Construction

A persistent theme of the Federal Circuit’s “broadening” holdings is that the district courts have overlooked the ordinary and accustomed meaning of claim terms.This is not to suggest the district courts are failing to make a concerted effort at the correct interpretation.On the contrary, the district courts, for the most part, pay close attention to decisions of the Federal Circuit and try to apply the claim construction doctrines accurately.

A principal error found by the Federal Circuit in many of the cases was the apparent importation of limitations from the specification to the claims.Our review indicates that the Federal Circuit, in compliance with Texas Digital Systems, Inc. v. Telegenix, Inc., 308 F.3d 1193 (Fed. Cir. 2002), and its progeny, is placing an increased emphasis on dictionaries and the need to ascertain the ordinary meaning of claim terms before consulting the intrinsic evidence.However, as illustrated by Inverness Medical Switzerland GmbH v. Warner Lambert Co., even when a district court adopts a claim construction framework in line with Texas Digital, the Federal Circuit is still prone to making corrections.Worse still for district courts, while in some cases the Federal Circuit seems to apply the Texas Digital framework, in others it appears to apply a less stringent framework.

1.Schwing GmbH v. Putzmeister Aktiengesellschaft

According to the Federal Circuit, the plain language of the claim did not support the district court’s construction.Schwing, 305 F.3d at 1324.First, the Federal Circuit noted a canon of claim construction that the district court failed to consider: “An invention claimed in purely structural terms generally resists functional limitation.”Id. (citing Toro Co. v. White Consol. Indus., Inc., 266 F.3d 1367, 1371 (Fed. Cir. 2001)).Second, the Federal Circuit looked to the plain language of the claims and determined that there was no facial evidence that the claims required the annular extensions to limit the radial expansion of the elastic sealing ring.Id.Third, the Federal Circuit reviewed the specification to determine if the patentee had defined

“annular extension” to include the radial expansion limitation.Id.While several of the disclosed embodiments did restrict radial expansion of the elastic sealing ring, the Court explained that this did not justify altering the plain language of the claims.Id.The Federal Circuit also reviewed the prosecution history and concluded that nothing in the prosecution history indicated Schwing had disavowed subject matter.Id. at 1324-25 (noting that, in viewing the prosecution history, the proper perspective is to consider whether any statements before the PTO would have lead a competitor to believe the patentee disclaimed subject matter).Moreover, the prosecution history referred to annular extensions in purely structural language.Id. at 1325.

2.RF Delaware, Inc. v. Pacific Keystone Technologies, Inc.