Sign up | Log in

CAFC: Cordis’s Stent Patents Not Infringed and Not Unenforceable for Inequitable Conduct

September 28, 2011

The U.S. Court of Appeals for the Federal Circuit on Sept. 28 affirmed a district court’s ruling that one Cordis Corp. blood vessel stent patent is not infringed by Boston Scientific, and that this patent and one other are not unenforceable for inequitable conduct.  (Cordis Corp. v. Boston Scientific Corp., Fed. Cir., No. 2010-1311, 9/28/11).

Artery Stent Patents.

This case involves two Cordis Corp. patents (U.S. Patent Nos. 5,879,370 and 5,643,312) covering stents with undulating longitudinal sections to help keep blood vessels open. Cordis sued Boston Scientific Corp., arguing that BSC’s NIR stent infringed the ’312 and ’370 patents. This particular dispute is only one installment in a long and expensive litigation saga known as the “Stent Wars,” the Federal Circuit said in a footnote, citing a New York Times October 4, 2007, article entitled “Keeping Arteries Cleared and the Courts Clogged.”

Cordis here appealed district court’s judgment as a matter of law (JMOL) that BSC did not literally infringe Claim 25 of the ‘370 patent. BSC cross-appealed the district court’s ruling that the ’370 and ‘312 patents are not unenforceable due to inequitable conduct.

Accused Stent Lacks ‘Undulating Sections.’

As to whether the NIR stent meets the “undulating sections” limitation of Claim 25, Cordis complained that BSC urged a narrower claim reading on the district court following the jury verdict.

However, Senior Judge Arthur Gajarsa said that no rule of law precluded BSC from seeking to clarify or defend the original scope of its claim construction. Likewise, he said that nothing barred the district court from clarifying its previous construction of the term “undulating.” Since Cordis did not challenge the district court’s construction of “undulating” as requiring “at least a crest and a trough,” there is no need to review the construction itself, Gajarsa said. Instead, focusing on the meaning of the claim construction, he cited a dictionary definition and found that the construction requires multiple “waves” like those in the ocean.

Agreeing with the district court’s conclusion that this definition of “undulating” suggested a change in direction, the appellate court affirmed the ruling that this limitation could not be satisfied by the merely curved structures (identified as U-loops and C-loops shown at Points A, B, and C in the pictured diagram) in the accused NIR stents. For support, the court noted that the patentees overcame an anticipation rejection by arguing that that the prostatic stent disclosed in the Garber patent (5,269,802) lacked the “undulating shape or contour” required by the claims of their invention.

The Federal Circuit, finding that the district court correctly held that the jury verdict lacked substantial evidence, upheld the JMOL of no literal infringement. “Substantial evidence, as required to support the jury’s verdict, demands more than a mere scintilla,” Gajarsa wrote.

Credibility of Patentee’s Explanation Rebuts Evidence of Intent to Deceive.

The district court initially found the ‘312 and ‘370 patents unenforceable based on inequitable conduct by the patentees during prosecution at the Patent and Trademark Office. The district court said that “[t]he patentees purposefully neglected their responsibility of candor to the responsibility of candor to the PTO by ‘putting their heads in the sand’ regarding prior art related to [undulating longitudinals].” This finding scrutinized the patentees’ handling of the prior art Hillstead patent (4,856,516) (shown in Figure 2A). Though the patentees disclosed Hillstead, the district court was critical of the way that they placed it among 70 references and gave it no special attention. Thus, the court considered Hillstead a material reference and found that the patentees intended to deceive the Patent and Trademark Office during prosecution.

In a 2006 ruling, the Federal Circuit agreed that the Hillstead reference was material, but remanded for additional findings regarding intent to deceive.

On remand, the district court said, “[u]pon further reflection, the evidence of record that tends to support a finding of deceptive intent is not clear and convincing.” The district court was persuaded by inventor Robert Fischell’s testimony that in July 1995 his attorney forwarded him a copy of a European Patent Office Search Report identifying Hillstead, and that the attorney drew attention to a different reference—Sgro—as the “only reference . . . being particularly relevant.”  Fischell consistently testified that, while he looked at the Sgro reference in 1995, he did not recall reviewing Hillstead until after the ’312 patent had issued. The district court found that no communications in the record called Hillstead to Fischell’s attention until after the ’312 patent issued, and that Fischell relied on his attorney’s advice vis-à-vis the EPO Search Report.

Given the credibility granted to the testimony that Fischell relied on attorney advice, the Federal Circuit here found no clear error in the district court’s conclusion that the evidence does not unequivocally show specific intent to deceive. In a footnote, the court explained:

This appears to be a case where BSC proved the threshold level of intent to deceive, but that proof was rebutted by Robert Fischell’s good faith explanation. … BSC’s argument therefore hinges, as it did below, on Robert Fischell’s credibility. Reviewing the record, we agree that there is substantial evidence calling into question Robert Fischell’s veracity. But it was the province of the district court to determine credibility, and “[t]his court gives great deference to the district court’s decisions regarding credibility of witnesses.…

The Federal Circuit affirmed the district court’s JMOL that Claim 25 of the ‘370 patent is not literally infringed by the NIR stent, and affirmed the district court’s conclusion that ’the 312 and ‘370 patents are not unenforceable for inequitable conduct.

The opinion was joined by Senior Judge Haldane Robert Mayer and Judge William C. Bryson.

Cordis was represented by Gregory L. Diskant of Patterson Belknap Webb & Ty-ler, New York. Boston Scientific was represented by Frank P. Porcelli of Fish & Richardson, Boston.

Read the Cordis Corp. v. Boston Scientific Corp. opinion.

Other articles:

Powered By relatedArticle