By: William G. Kratz, Jr. 

The Honeywell International, Inc. v. Hamilton Sundstrand Corp. decision of April 18,2008 expands the application of the doctrine of prosecution history (file wrapper) estoppel. Here, the Court of Appeals for the Federal Circuit (C.A.F.C.) concluded that the rewriting of a dependent claim into an independent claim (even though the examiner did not reject the dependent claim on the basis of prior art), coupled with the cancellation of the original independent claim, creates a presumption that the applicant incorporated limitation of the rejected independent claim into the rewritten claim, and thus, a presumption of surrender of certain claim limitations and prosecution history estoppel.

In relying on the case of Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co. (Festo DO, the C.A.F.C. stated that the presumption of surrender of certain claim limitations in a prosecution history estoppel could be rebutted by demonstrating that: (1) „the alleged equivalent [of the surrendered claim limitation in the dependent claim] would have been unforeseeable at the time of the narrowing amendment,“ (2) „the rationale underlying the narrowing amendment bore no more than a tangential relation to the equivalent in question,“ or (3) „that there was ’some other reason‘ suggesting that the patentee could not reasonably have been expected to have described the alleged equivalent.“ The court in Honeywell found no such rebuttal; that is, the presumption of surrender of the subject claim limitation prevails, and prosecution history estoppel is applied to the rewriting of the dependent claim into the independent claim. As to foreseeability, the court found that Honeywell did not rebut the presumption of surrender with evidence of unforeseeability, and that the prosecution history reveals no reason for the narrowing amendment and, since silence does not overcome the presumption, the presumption of surrender was ngt rebutted.

In a dissenting opinion, Judge Newman argued that: „The court today applies its new presumption of surrender to all equivalents of the claim elements and limitations that originated in dependent claims that were never amended and that were not the subject of prosecution history estoppel.“ Because there is no prosecution history that narrowed the dependent claim element at issue, Judge Newman would not apply the presumption of surrender under the doctrine of prosecution history estoppel. Judge Newman further stated that: „My colleagues held that since there was no narrowing amendment or limiting argument during prosecution of the Honeywell dependent claims, surrender of the entire universe of potential equivalents is presumed when the original independent claim is canceled,“ and argued that such a conclusion places new constraints on the patentee’s access to the doctrine of equivalents.–click here to read more—