An en banc panel of the U.S. Court of Appeals for the Federal Circuit held that the Festo presumption of surrender of equivalence applies where the applicant rewrites dependent claims into independent form, canceling the original independent claims that were determined to be unpatentable by the examiner, even though the claim limitations in the dependent claims were never amended. Honeywell International Inc. v. Hamilton Sunstrand Corporation, Case No. 02-1005-1082 (Fed. Cir. June 2, 2004) (Dyk, J.).
Honeywell sued Sunstrand for infringing certain claims directed to an aircraft auxiliary power unit (APU) and, in particular, the means for controlling airflow instability, or "surge," in the APU. Each of the claims at issue requires the APU to include "inlet guide veins" and requires the operation of the surge bleed valve to be a function of inlet guide vein position. The originally filed independent claims did not include any limitations relating to inlet guide veins or their position; these limitations were contained only in dependent claims. During prosecution, the independent claims were rejected as obvious. The examiner indicated that dependent claims would be allowed if rewritten into independent form, which the applicant did.
The district court denied Sunstrand’s motion for summary judgment on the issue of prosecution history estoppel, and the jury returned a verdict of infringement under the doctrine of equivalence. Both parties appealed.
The cross-appeal was originally heard by a panel of the Federal Circuit, followed by the Court’s sua sponte en banc review of the issue of prosecution history estoppel. The majority of the en banc panel ruled the Festo presumption of surrender applies where there is either a narrowing amendment, or the scope of subject matter is narrowed through a new claim limitation added by amendment. The Court compared the original independent claims with the new independent claims, concluding that the new independent claims included a limitation added by amendment. The Court expressly rejected Honeywell’s argument that the presumption of surrender should not apply because the scope of the rewritten claims themselves had not been narrowed. The fact that the scope of the rewritten claim remained unchanged did not preclude prosecution history estoppel where, by canceling the originally independent claim and rewriting the dependent claims into independent form, the scope of the subject matter claimed in the original independent claim has been narrowed to secure the patent. The Federal Circuit’s focus was on the comparison of the scope of the independent claims as originally drafted and as amended.
Judge Newman dissented, arguing that restating a dependent claim in independent form is not a change in scope when the element added from the dependent claim was not initially contained in the independent claim. Judge Newman reasoned that the antecedent independent claim did not mention any inlet guide vein, and, therefore, the inlet guide vein element was not amended or narrowed at any time during the prosecution. She focused on a comparison between the dependent claim as initially drafted and as rewritten in independent form, rather than the majority’s comparison between the independent claim as originally drafted and the independent claim as amended. The dissent noted the havoc the Court’s majority opinion is likely to inflict on the prosecution process, since it will provide a strong incentive for applicants to file and prosecute far more independent claims than would traditionally be prosecuted using a dependent claim structure. Such change will drive up the cost of prosecution, complicating the job for the examiner and applicant alike.
Practice Note: The Honeywell case, coupled with the recent Federal Circuit decisions in Deering Precision Instruments and Ranbaxy Pharmaceuticals, reflect the Federal Circuit’s preference for bright lines and absolute tests for application of the Festo presumption of surrender. This trio of cases provides a strong incentive to draft claims in independent form, as any instance where a dependent claim is redrafted into independent form, coupled with the cancellation of the antecedent independent claims, will trigger the Festo estoppel.
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