Colibri Heart Valve LLC v. Medtronic Corevalve, LLC

Authored by: Jeremy J. Gustrowsky

In a significant patent law decision, the Federal Circuit reversed a $106 million jury verdict in favor of Colibri Heart Valve LLC against Medtronic CoreValve, LLC, ruling that Colibri was barred from claiming infringement under the doctrine of equivalents. The dispute centered on U.S. Patent No. 8,900,294, which covers a method for implanting artificial heart valves that allows surgeons to partially deploy and then recapture the valve if its positioning is off. Colibri accused Medtronic’s Evolut heart valve products of infringing this patent, specifically focusing on how the devices deploy the valve inside a patient.

The key legal issue was whether Colibri could claim that Medtronic’s method of deploying the valve—by retracting a sheath while applying a pushing force—was equivalent to Colibri’s patented method, which specifically described “pushing out the pusher member from the moveable sheath.” During the patent’s prosecution, Colibri had canceled a claim that covered “retracting the moveable sheath,” but kept a claim that required “pushing out” the pusher member. At trial, Colibri abandoned its argument of literal infringement and relied solely on the doctrine of equivalents, which allows a patent owner to claim infringement even if the accused product or method does not exactly match the patent’s wording.

The Federal Circuit held that Colibri’s cancellation of the “retracting” claim during prosecution created prosecution history estoppel—a legal doctrine that prevents a patent owner from later recapturing, through the doctrine of equivalents, subject matter it gave up to get the patent granted in the first place. The court found that the canceled and retained claims were closely related, and that Colibri’s own arguments about “basic physics” showed that pushing and retracting were intertwined in the deployment process. As a result, Colibri could not now argue that Medtronic’s method, which used retraction, was equivalent to its patented method, which required pushing.

This decision highlights the importance of careful claim drafting and prosecution strategy for patent owners. By canceling certain claims during prosecution, a patent owner may inadvertently limit the scope of protection available later, especially under the doctrine of equivalents. For companies facing infringement suits, this case demonstrates the power of prosecution history estoppel as a defense, potentially overturning large jury verdicts.