Upholding the lower court’s summary judgment of non-infringement, the U.S. Court of Appeals for the Federal Circuit held that a claim preamble describing structural features of an element designed to be used with the claimed object limited the scope of the claim. The Court affirmed that when the structural features recited in a preamble are necessary in order to give meaning to limitations in the body of the claim itself, the preamble limits the claim. Bicon, Inc. and Diro, Inc., v. The Straumann Company and Institut Straumann AG. (Fed. Cir. Mar. 20, 2006) (Bryson, J.).
The patent holder Diro sued Straumann for patent infringement, joined by its licensee Bicon. The claim-in-suit was directed to a plastic cuff for use in dental implant procedures. The claimed cuff was designed to be used with an abutment member that is attached to a root member implanted in a patient’s jaw bone and which sticks above the patient’s gum line.
A lengthy preamble to the claim-in-suit recited detailed structural features of the abutment member, which in turn were referenced in the main body of the claim in order to recite the structure of the cuff. In particular, the preamble stated that the abutment member "has a frusto-spherical basal surface portion and a conical surface portion." The body of the claim recited limitations that the cuff include a bore "having a taper generally matching that of the conical surface portion of the abutment" and the distance between the two ends of the bore be "less than the height of the conical surface."
The Federal Circuit affirmed, finding there was no infringement either literally or under the doctrine of equivalents because the accused devices did not include the limitations recited in the preamble. The Federal Circuit rejected Straumann’s argument that the preamble does not limit the claim because it merely sets forth the purpose or use of the cuff member. The Court noted that the preamble recited structure for the abutment going well beyond what is necessary to describe the intended purpose of the cuff, and the Court further noted that the limitations in the body of the claim relied upon and derived antecedent basis from the preamble. Because the claim defines the cuff in a way that depends on the physical characteristics of the abutment member, as described in the preamble, the Court concluded that the invention recited in the claim-in-suit should be understood as being limited by the abutment recited in the preamble.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.