All Alerts & Newsletters

Patent Claim Term’s Definition Redefinition Permitted Despite Absence In Specification


Despite the absence of claim terminology anywhere in a patent’s written description, a divided Federal Circuit panel concludes that the patent specification and prosecution history can suggest redefinition of that terminology in Honeywell International, Inc. v. Universal Avionics Systems Corp., et al. (Nos. 2006-1406, -1435, July 3, 2007).

Honeywell filed suit alleging that Universal infringed a claim of its patent that specified provision of a signal representative of aircraft and runway alignment by determining the angle between the runway and the heading of the aircraft. Following a finding that Universal’s accused product infringed the asserted claim, the district court entered judgment and awarded damages to Honeywell. Universal appealed, arguing, inter alia, that the district court erred in construing the term “heading of the aircraft.”

Although the term “heading” is absent from the patent’s written description, the panel majority affirms. The only form of alignment disclosed by the specification depends on the direction of the aircraft from the runway. The specification and prosecution history both make clear that the patentees used the claim term “heading” to refer to the angular direction of an aircraft from a point on a runway (i.e., what is conventionally known as the aircraft’s bearing), not the direction in which the aircraft is pointing (i.e., what is conventionally known as the aircraft’s heading).


Email Twitter LinkedIn Facebook Google+

For more information, please contact the professional(s) listed below, or your regular Crowell & Moring contact.

Richard R. Diefendorf
Counsel – Washington, D.C.
Phone: +1 202.624.2758