View source for Mitros: Defense of Hamilton Sundstrand (4/4/2011)

The basis of the defense for Hamilton Sundstrand revolves around two issues. These two issues are whether Hamilton’s invention APS 3200 infringed upon Honeywell’s ‘194 and ‘893 patents by the doctrine of equivalence based off of foreseeability and tangential relation. This argument will focus specifically on the issue of foreseeability. 
Before focusing on this issue, it is important to remember that it is the responsibility of the patentee to fully disclose and document their invention under section 112 such that a person containing ordinary skill in the art would be able to replicate the invention without further experimentation. Additionally, as set forth in the case of Graver Tank v. Linde Air Products, a patentee can claim infringement through the doctrine of equivalence if an invention accomplishes essentially the same result through essentially the same means. As further put forth in the case of Warner-Jenkinson v. Hilton Davis, the best way to determine equivalence is to examine each claim on an element by element basis in order to determine equivalence between the elements of two different inventions.
As related to this case, the foreseeability criterion weakens Honeywell’s claims of infringement through equivalence. The foreseeability criterion asks whether the alleged equivalent would have been unforeseeable to one of ordinary skill in the art at the time of the amendment. Since it would be unreasonable to expect someone to anticipate the state of technology a few years in the future from their initial filing, foreseeability gives the patentee some leadway in their patent claims in conjunction with the doctrine of equivalence. However, the emphasis here is whether the equivalent element would have been obvious to the fictional person of ordinary skill in the art, not whether the equivalent was obvious to the patentee at the time of their application. Because the purpose of the patent laws are to advance the scientific arts and provide a means of informing the public of what is considered to be publicly available for use, our concern is not with placating the patentee, but accomplishing these two primary goals. The foreseeability criterion attempts to strike a balance between these two goals and protecting the patentee to such an extent as to encourage them to file for a patent. In the case at hand, there has been expert testimony claiming that in 1982, the year of Honeywell’s invention, the items found within the Hamilton Sundstrand invention would have been obvious to a person of ordinary skill in the art. Additionally, the prior art contains the L1011 device as well as the Glennon patent, both of which were developed in the 1970’s and contain some of the key teachings that the Sundstrand invention utilizes. Therefore, in light of the hypothetical person of ordinary skill in the art, one would have to assume that the items of the Sundstrand invention would have been foreseeable to the hypothetical person of ordinary skill in the art.
In light of this evidence, the Court must find that the development of the Sundstrand device was foreseeable to a person of ordinary skill in the art at the time Honeywell filed its patents. As a result of this, it was the responsibility of Honeywell to draft its claims in such a manner as to contain the elements found in Sundstrand invention as well as their orientation and use within the Sundstrand invention if they desired protection on the item. Although Honeywell claims ignorance on the topic, what Honeywell knew is irrelevant to the purpose of the patent laws and the issue at the heart of this debate. Rather, the key issue is on the ordinary person in the art. In light of this and the evidence presented, one must conclude that Sundstrand is innocent of the charges of infringement brought against it.