HE LINES for another doctrine of equivalents battle between the Court of Appeals for the Federal Circuit and the U.S. Supreme Court might have just been drawn with the March 28, 2002, en banc decision of the Federal Circuit in Johnson & Johnston v. R.E. Service Co.[1]� The last two en banc decisions of the Federal Circuit concerning the doctrine of equivalents resulted in the grant of certiorari, which is relatively rare in patent cases.
In the first case, Warner-Jenkinson Co. v. Hilton Davis Chemical Co.,[2]� the Supreme Court reversed the Federal Circuit for not considering all the requirements for application of prosecution history estoppel as a bar to the doctrine of equivalents. The second case, Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co.,[3]� which also involves the proper application of the prosecution history estoppel bar to the doctrine of equivalents, is pending decision by the Supreme Court, which heard arguments in January. However, the general perception in the patent bar, based on analysis of the oral argument, is that the Court may very well disagree once again with aspects of the Federal Circuit’s analysis of the doctrine of equivalents.
