concurring in the judgment, dissenting in part.
On review of the facts and law of this case, I reach the same result as does the court. However, I do not endorse the new ruling that an unamended claim is barred from access to any degree of equivalency simply because a broader claim was amended during prosecution.
It has long been the law that estoppel affects the scope of equivalents available to an unamended claim, when a broader claim is amended for reasons of patentability. That was the holding in Builders Concrete, Inc. v. Bremerton Concrete Products Co., 757 F.2d 255, 260, 225 USPQ 240, 243 (Fed.Cir.1985), and reflects the traditional *1370rules of estoppel. It is properly applied in reexamination, as the court’s opinion explains. However, the court today enlarges that estoppel to enhance the absolute bar of Festo, even though the claim was not amended. The court thus holds that the amendment of a broader claim bars access to any scope of equivalency as to the unamended narrower claim, whether or not the accused infringer is practicing subject matter that was required to be relinquished. In Festo this court did not go so far; I see no need to do so in order to respect the principles of Festo.
Festo does not prevent an unamended claim from serving as a source of equivalency, subject to estoppel against recovering by equivalency the subject matter that was relinquished in order to achieve pat-entability of a different claim. This decision, by extending the Festo absolute bar to such unamended claims, will give the coup de grace to this vestige of the doctrine of equivalents. The consequences for patent prosecution, with its traditional presentation of claims of diminishing scope, have not been explored by the parties or by the court. I respectfully dissent from the majority’s ruling on this aspect.