Issue 05/21 | June 21, 2005
A Broad Definition of a Claim Term Supported by Extrinsic Evidence Will Not Overcome a Narrower Definition Provided in the Specification

In Boss Control, Inc. v. Bombardier Inc. , Nos. 04-1437, -1438, -1471, (Fed. Cir. June 8, 2005), the federal circuit affirmed a district court grant of summary judgment of noninfringement in favor of Bombardier, upholding the district court’s claim construction which relied principally upon intrinsic evidence.

Boss’s ‘206 patent is directed to a power interrupt apparatus that prevents the unauthorized use of, e.g., snowmobiles and sports watercraft, by interrupting electrical power to the vehicle in a first stage that allows auxiliary electrical equipment to operate, and thereafter in a second stage wherein all power is shut off. The accused devices immediately switch off the vehicle when the connection to the control apparatus is broken. The district court construed interrupt in the language “wherein said controller is operative to interrupt power” as meaning a staged power cut-off in view of the specification, and granted Bombardier summary judgment of noninfringement.

On appeal, Boss argued the district court erred by not employing the ordinary and accustomed meaning of “interrupt” "to cut off or switch off." But the federal circuit was unpersuaded, relying on the applicant’s statements in the ‘206 patent specification distinguishing the claimed invention from prior art devices that only provided for on-off control. The Background and the preferred embodiments clearly demonstrated that “interrupt” was given a more detailed definition compared to the simple on-off control definition provided by dictionaries and urged by Boss. The federal circuit held that extrinsic evidence of the meaning of “interrupt” could not overcome the narrower definition supplied by the specification, and affirmed the JMOL grant based on the district court’s claim construction.

The case is another in a line of decisions since C.R.Bard last October wherein the court has applied a claim construction methodology that makes clear the role of the specification and the intrinsic evidence, and in a manner that foretells of a likely outcome in the pending Phillips case.

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To discuss these topics further, please feel free to contact the author Michael R. Dzwonczyk, (mdzwonczyk@sughrue.com), at Sughrue Mion, PLLC in Washington DC, USA.

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