By Kevin E. Noonan — After more than two decades of being the red-headed stepchild of patent infringement before the Federal Circuit, infringement under the doctrine of equivalents has made a dramatic comeback in the past few years, the Court affirming plaintiffs asserting their patents under the doctrine six times (versus denying DOE infringement on the basis of prosecution history estoppel twice, on the basis of the dedication-disclaimer estoppel twice, and finding no equivalents twice). One of those affirmances was in Eli Lilly & Co. v. Hospira, Inc., directed to the same patent and with assertion of infringement under the…
