In a July 18 precedential decision in Colibri Heart Valve LLC v. Medtronic CoreValve LLC, the U.S. Court of Appeals for the Federal Circuit overturned a $106 million jury verdict against Medtronic for infringement of a patent on a method of deploying an artificial heart valve. The jury found that Medtronic induced infringement under the doctrine of equivalents and awarded damages. On appeal, the Federal Circuit held that the patentee’s cancellation of a related claim gave rise to prosecution history estoppel that barred the infringement claim against Medtronic under the doctrine of equivalents.
Background
The patentee, Colibri, originally filed an application with two independent method claims. Claim 34, which became issued claim 1, recited a method of “partially deploying . . . the replacement heart valve . . . by pushing out the pusher member from the moveable sheath to expose the distal portion of the replacement heart valve device . . . .” Claim 39, which was rejected during examination for lack of written description support and subsequently cancelled by Calibri, recited a method “partially deploying . . . the replacement heart valve . . . by retracting the moveable sheath . . .” [emphasis added].
Medtronic’s partial-deployment method consisted of applying a force to hold the replacement heart valve in place while retracting the moveable sheath. Colibri argued that Medtronic’s method was equivalent to the claimed method of applying a force to push the heart valve out of the moveable sheath. According to Colibri, “basic physics” requires that opposing forces (i.e., pushing and retracting) be applied to deploy the valve from the moveable sheath.
Medtronic moved for judgment as a matter of law on the ground that prosecution history estoppel barred the patentee from asserting infringement under the doctrine of equivalents. The district court denied Medtronic’s motion on the ground that claim 34 (issued claim 1) and claim 39 were separate independent claims, and that the patentee did not add or amend any claims directed to the “pushing” limitation.
Key Findings
The Federal Circuit held that cancellation of a separate independent claim, not just amending the claim language, may constitute a narrowing amendment, and thereby give rise to prosecution history estoppel regarding the claim scope that was surrendered. The court stated:
Colibri’s cancelling of claim 39 in favor of pursuing limitations that already appeared in retained claim 34 (issued claim 1) was a narrowing amendment giving rise to prosecution history estoppel. . . . Narrowing is a prerequisite to prosecution history estoppel: “If the amendment was not narrowing, then prosecution history estoppel does not apply.” Festo, 344 F.3d at 1366. But the required narrowing is not a purely formal matter of altering a single claim’s terms; it can exist, and we conclude here does exist, as a substantive matter based on cancelling a closely related claim involving such intertwined terminology that cancelling one claim necessarily communicated that the scope of the other claim had narrowed.
Quoting from the seminal Supreme Court decision in Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co. (2002), (“Estoppel is a ‘rule of patent construction’ that ensures that claims are interpreted by reference to those ‘that have been cancelled or rejected.’”), the Federal Circuit held that estoppel is not limited to situations in which the issued, asserted claim itself was amended:
[W]e reject Colibri’s contention that claim 1 itself had to be amended for prosecution history estoppel to apply. The close substantive relationship between the cancelled and retained claims, by Colibri’s own basic-physics logic for its affirmative assertion of equivalence, is enough to cross the estoppel threshold. A skilled artisan reading the prosecution history would understand that some narrowing had occurred through cancelling claim 39.
Practice Tips
While the Federal Circuit decision makes clear that prosecution history estoppel can arise from cancelling claims during prosecution, in addition to introducing narrowing claim amendments, the court also took pains to point out several other possibilities the patentee can pursue:
[I]n the absence of further arguments about the scope of narrowing or exceptions to the presumption of estoppel, the doctrine of equivalents became unavailable to Colibri for the issued claim 1. If Colibri wished to capture territory involving retraction that was outside the literal scope of claim 1, it could have filed a continuation application (and there sought to show written-description support).
If you have questions about the impact of this ruling on current or future patent strategy, please contact William Scofield, or reach out to your regular Lathrop GPM attorney.