Kemnetz: Brief for Honeywell 04/04
In the case of Honeywell Intern., Inc. v. Hamilton Sundstrand, the Court has incorrectly applied prosecution history estoppel, unfairly preventing Honeywell from being action against Hamilton Sundstrand involving infringement of Honeywell’s patent. In an amendment process of the patent, Honeywell changed a dependent claim to an independent claim, which is standard protocol in the patent application process. This change was made due to a rejection of the application because of prior art. When amendments are made, there is a presumption of surrender of any equivalents that pertain to the pre-amendment claims, however the Court ruled that this surrender also pertained to any dependent claims that were not amended and therefore should not have been subject to prosecution history estoppel. The IGVs used in Honeywell’s patent were part of the dependent claims not amended. This “unlimited surrender” does not follow the correct application of prosecution history estoppel, and therefore should not be applied.
Honeywell’s amendment from dependent claims into independent form effectively included the IGVs to the patent claim. Simply because an element is added through amendment does not make it non-applicable when considering equivalents. Going element by element, the IGVs appearing in the original claims, and the fact that those claims were not revised, should be considered as an element to use in the evaluation of equivalence.
The Warner case involving estoppel was valid because of distinct diversion from clear limits set in the patent. This case does not involve any diversion from limits set in the Honeywell patent. As for foreseeability, Sundstrand claims that their device and use of the IGV was unique, but somehow also foreseeable in the application of the Honeywell patent. If the application of the IGVs was foreseeable, why did it take 10 years plus for Sundstrand to successfully apply it in such a way? The sheer time frame of over a decade renders Sundstrand’s foreseeability argument invalid. The question of foreseeability is also in great contrast to the question of application of the doctrine of equivalence. If a device is not literally equivalent, but still can be considered equivalent, the doctrine of equivalence applies and protects the patent owner from infringement. The foreseeability criteria counteracts this protection, and should not be applied. Including foreseeability criteria, such as in this case, would greatly decrease the protection provided to countless patent owners.
Since estoppel should not have been applied in this case, the doctrine of equivalence should stand and be applied element by element to Sundstrand’s device. IGVs are the main focus of the infringement in this case, and since they should not be considered as surrendered in Honeywell’s patent, they should be included when applying the doctrine of equivalence.