In the decision regarding the case of Honeywell Inc. v. Hamilton Sundstrand Corp., I rule in favor of Hamilton Sundstrand.
In the trial both sides made their case for whether the patent was or was not valid and whether there was or was not infringement of the patent. Honeywell argued that although they were forced to concede an independent claim in their original patent application, the loss of this claim should not have affected the dependent claims about IGVs. They stressed that the patent should be considered element-by-element and not as a whole. They also claim that the subject matter that was lost did not appear as a revision and that Sundstrand’s claims that occurred a decade later were not unique. Honeywell claims infringement because every element of the Sundstrand IGV method can be found in Honeywell’s original method and that Sundstrand has simply added another step that is not unique and is therefore infringing by the doctrine of equivalence.
Hamilton Sundstrand countered with their own interpretation of the facts of the case and the relevant statutes. The Sundstrand attorneys argued for estoppel in its broadest sense. Sundstrand believes that they should not be punished for what is essentially incompetence on the part of Honeywell for poorly laid out claims in the Honeywell patent. They also said that patent markings on the Honeywell products were not fulfilled. Most importantly though, Sundstrand claims that since Honeywell gave up information in the estoppels the doctrine of equivalence is no longer applicable and there is no infringement.
Honeywell responded by saying that marking is optional and in the event of a failure to mark they concede that no damages can be collected until the infringing party is notified of their infringement. They challenged Sundstrand to provide evidence for why the Honeywell patent is invalid. They believe that their patent is valid and provide the evidence of its acceptance by the U.S. patent office as proof of its validity. They elaborated on the fact that Sundstrand added only one element to the device and that this method of a high and low flow element is not unique and maintain infringement by the doctrine of equivalence, but recognize that there is not literal infringement.
Sundstrand made their next response. They appeal to foreseeability more in this argument. Estoppel they say, prevents the patent holder from using the doctrine of equivalence to claim infringement. They say that infringement cannot be claimed on elements of the patent that could have been foreseen at the time of the invention. They cite the fact that the double solution problem that they added to the device only took two months to solve. This speaks to the fact that the element was foreseeable.
Honeywell’s final response attempted to boil down the case to a single issue which was the issue of foreseeability. They claim that the Sundstrand claims infringement solely because the doctrine of equivalence is invalid if an element of the invention was foreseeable. They say that the element was not foreseeable as evidenced by the fact that a decade went by between the addition of the element to the invention and the original invention. They argue that estoppels cannot be claimed because the dependent claims of the original patent should not be lost.
In Sundstrand’s final response they say that the district court held that it was intuitive for IGVs to distinguish between high and low flow and that this also shows foreseeablility.
I rule in favor of Hamilton Sundstrand. They should not be punished for Honeywell’s inability to clearly lay out the claims of their patent and restructure the claims after the initial abandonment of the claims. I believe that Hamilton Sundstrand’s addition is a useful addition and one that should have been foreseeable to Honeywell and therefore disallows the application of the doctrine of equivalence. Since there is no literal infringement in this case and the doctrine of equivalence is disallowed there is no infringement.