In Advanced Cardiovascular Sys, Inc. v. Medtronic Vascular, Inc., Civ. Case Nos. 05-1280, 05-1281, 05-1282 (Fed Cir. May 26, 2006) (non-precedential), the Federal Circuit affirmed a district court decision of granting a summary judgment of non-infringement of Medtronic’s U.S. Patent No. 5,292,331 (the ‘331 patent), U.S. Patent No. 5,674,278 (the ‘278 patent), U.S. Patent No. 5,879,382 (the ‘382 patent), and U.S. Patent No. 6,344,053 (the ‘053 patent), which are drawn to stent devices and methods of delivery and manufacture and all of which are related patents.
In interpreting the claims of the ‘331, ’278, ‘382, and the ‘053 patents at trial, the District Court had found that the terms “circular member,” “stent member,” “ring,” and endovascular support member” have the same meaning as a “stent.” The Federal Circuit upheld this construction since, while used in different claims and in different patents, these terms had no clear meaning from the specification and were “employed in a manner analogous to and interchangeable with the term ‘stent’.”
Further, in interpreting the term “stent,” the District Court found that Medtronic had clearly disavowed any stent not having straight segments ending at peaks. Specifically, during prosecution of the ‘331 patent, Medtronic asserted that the invention distinguished over the prior art since the stent used substantially straight segments connected to form ends, and that the ends must be at top or bottom. The Federal Circuit agreed that this assertion in prosecution was sufficient to disavow any additional element being used on the recited stent ends.
Moreover, even though the disavowal was arguably broader than necessary to overcome the prior art, the Federal Circuit held that “’there is no principle of patent law that the scope of a surrender of subject matter during prosecution is limited to what is absolutely necessary to avoid a prior art reference …. Norian Corp. v. Stryker Corp., 432 F.3d 1356, 1361-62 (Fed. Cir. 2005).” Since the broader disclaimer was applied to the claims of the ‘331 patent, this same disavowal applied to the remaining continuation patents: the ‘278 patent, the ‘382 patent, and the ‘053 patent. The Federal Circuit relied upon a statement in the prosecution of each of the ‘278 patent, the ‘382 patent, and the ‘053 patent that the claims were allowable “for at least the same reasons as the parent application.”
Also, while acknowledging that certain of the claims, such as in the ‘053 patent, do not recite an “end,” the Federal Circuit found that the claims instead recited a “turn.” The Federal Circuit held that, since the specification and claims use the term “turn” synonymously with “end,” the claims of the ‘053 patent also recite an end and are subject to the disavowal in the parent application.
Lastly, the Federal Circuit found that no doctrine of equivalents was available for the recited “stent” and the synonymous terms in any of the patents due to prosecution history estoppel caused by the broad disavowal in the ‘331 patent.
Significance to Patent Owner
This case is a further reminder that, In view of Phillips, the Federal Circuit will look to uses and disclaimers in related applications to disclaim certain features for what would otherwise be a broad claim term. Therefore, it is remember that what is asserted in one related case can be used in another related case. Thus, it is important to ensure that applicant’s take steps to ensure that arguments from one application are not automatically applied in another application, and, if at all possible, to use differing claim language to help prevent claim interpretations from one related case becoming the interpretations for all of the cases.