The U.S. Court of Appeals for the Federal Circuit affirmed a district court's decision granting summary judgment of non-infringement holding that the accused device did not infringe literally or under the doctrine of equivalents due to prosecution history estoppel. Helena Laboratories Corp. v. Alpha Scientific Corp., Case No. 07-1503, (Fed. Cir., April 16, 2008) (Moore, J.).
The case stemmed from a declaratory action brought in the U.S. District Court for the Eastern District of Texas by Helena Laboratories that asserted non-infringement and invalidity of Alpha Scientific's patent directed to medical dispensing devices. Helena conceded that its device, the H-Pette 3611, met all the elements of the claimed device, other than the "stabilizing supports" claimed in the patent-in-suit.
In construing the claims, the Federal Circuit found that the "stabilizing supports" of the patent-in-suit were defined as a plurality of flange-like structures, which contacted the target surface at multiple points. Because of the stabilizing supports, a user was able to place the dispensing tip at a predetermined distance from the target surface, allowing for delivery of a desired volume of fluid into a container.
On analyzing literal infringement, the court held that contrary to the claimed apparatus, the H-Pette, at most, possessed a single stabilizing support and was incapable of delivering a predetermined volume of fluid. In analyzing infringement under the doctrine of equivalents, the court held that Alpha's claim was barred due to prosecution history estoppel. The panel noted that during prosecution Alpha successfully overcame an obviousness rejection by distinguishing the cited prior art as being incapable of dispensing a predetermined volume of fluid and that key to the invention was the plurality of stabilizing supports which kept the dispensing portion of the device at a predetermined distance from the target surface.
Practice Note: This ruling serves as a reminder that a patentee who clearly and unmistakably surrendered claim scope through arguments made to an examiner during prosecution will not be able to later assert infringement under the doctrine of equivalents.
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.