Federal Circuit Reverses $106M Verdict, Finding Doctrine of Equivalents Barred by Prosecution History Estoppel

In Colibri Heart Valve LLC v. Medtronic CoreValve, LLC, No. 2023-2153 (Fed. Cir. July 18, 2025), the Federal Circuit reversed the district court’s denial of Medtronic’s motion for judgment as a matter of law (JMOL) on Colibri’s doctrine of equivalents infringement theory and held that theory barred by prosecution history estoppel.

Colibri alleged Medtronic induced infringement of U.S. Patent No. 8,900,294 by encouraging surgeons to use the patented method. The claimed method for implanting an artificial heart valve includes a step to partially deploy the device by “pushing out [a] pusher member from [a] movable sheath.” At trial, Colibri argued Medtronic’s technique of retracting a movable sheath infringed the “pushing” requirement under the doctrine of equivalents. A jury found for Colibri, awarding over $106 million in damages.

Medtronic moved for JMOL, contending prosecution history estoppel barred Colibri’s infringement theory. During prosecution, two independent claims were pending: one for “pushing out” the member and one for “retracting” the sheath. Colibri canceled the “retracting” claim following a written description rejection under 35 U.S.C. § 112. But the district court denied the motion, finding Colibri not estopped from its doctrine of equivalents theory.

On appeal, the Federal Circuit reversed. The Court reasoned Colibri’s cancelation of the retracting claim barred Colibri from asserting that retracting is equivalent to pushing. The Court found that, although the pending claims did not formally depend from one another, the claims differed only by the requirement to push or retract.  The Court thus determined the claims “closely related as a substantive matter, so giving up one communicates a narrowing message about the one retained,” which justified estoppel.