Appeals Court Affirms Inequitable Conduct Finding Despite Pre-Therasense Judgment

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By Tony Dutra  


• Case Summary: Sanofi-Aventis patent unenforceable for inequitable conduct.

• Key Takeaway: But-for materiality and specific intent affirmed despite pre-Therasense judgment by lower court.


Despite heightened standards, the U.S. Court of Appeals for the Federal Circuit affirmed April 9 a lower court's inequitable conduct judgment against drug maker Sanofi-Aventis (Aventis Pharma S.A. v. Hospira Inc., Fed. Cir., No. 2011-1018, 4/9/12).

The company's follow-on patents for administering the chemotherapy cancer drug Taxotere were consequently held unenforceable, freeing generic drug makers Apotex Inc. and Hospira Inc. to proceed with generic docetaxel.

The district court had found inequitable conduct under looser standards that were in effect prior to the Federal Circuit's en banc decision in Therasense Inc. v. Becton, Dickinson and Co., 649 F.3d 1276, 99 USPQ2d 1065 (Fed. Cir. 2011) (103 PTD, 5/27/11).

The appeals court applied the tighter Therasense standards and came to the same conclusion, thus putting in doubt post-Therasense predictions that inequitable conduct would be exceedingly difficult to prove.

Court Finds Patents Obvious.

Sanofi-Aventis U.S. LLC own patents (4,814,470; 5,750,561 and 5,714,512) on docetaxel, which it markets under the brand name Taxotere. The patents are assigned to Aventis Pharma S.A.

The '470 docetaxel composition patent expired. The other two patents are on the administration of the drug.

Apotex and Hospira sought to introduce generic versions of docetaxel. Sanofi sued the generic manufacturers in the U.S. District Court for the District of Delaware for infringement of the '561 and '512 patents.

Chief Judge Gregory M. Sleet found in favor of the defendants in two respects relevant to the appeal. 743 F. Supp. 2d 305 (D. Del. 2010).

First, he denied Sanofi's requests to narrow the asserted claims' scope to avoid the prior art. He thus found the claims invalid for obviousness in light of two French language references known as GV and Vidal.

Inequitable Conduct Finding in Lower Court.

Second, Sleet found that the named inventor, Jean-Louis Fabre, had deliberately withheld from the Patent and Trademark Office the GV and Vidal references, despite knowing that they were material to patentability of the '561 and '512 patents.

Sleet made that finding under materiality and intent standards that have since been overridden by Therasense. First, he used the PTO's “Rule 56,” 37 C.F.R. §1.56(b), whereby new information is material if it establishes either a prima facie case of unpatentability, or if it refutes or is inconsistent with a position the applicant took before the PTO.

The Therasense court rejected that approach in favor of a but-for materiality standard, requiring the challenger to show that “the PTO would not have allowed a claim had it been aware of the undisclosed prior art.”

As to the intent prong of inequitable conduct, Sleet also said, “The more material the information misrepresented or withheld by the applicant, the less evidence of intent will be required in order to find inequitable conduct.”

The Federal Circuit in Therasense eliminated any notion of such a “sliding scale.” The court clarified that the intent prong is satisfied only by a showing of specific intent, that “the applicant knew of the reference, knew that it was material, and made a deliberate decision to withhold it.”

Sanofi appealed the inequitable conduct decision, as well as the lower court's judgments on claim construction and obviousness.

Claim Construction, Obviousness Judgments Upheld.

Judge Sharon Prost affirmed the claim construction decisions first, and consequently agreed with the lower court that the asserted claims were invalid for obviousness.

In general, the court applied its “recently reiterated … stringent standard for narrowing a claim beyond its plain and ordinary meaning,” in Thorner v. Sony Computer Entertainment America LLC, 669 F.3d 1362, 101 USPQ2d 1457 (Fed. Cir. 2012) (22 PTD, 2/3/12).

Quoting Thorner, the instant court said, “we will only interpret a claim term more narrowly than its ordinary meaning under two circumstances: '1) when a patentee sets out a definition and acts as [its] own lexicographer, or 2) when the patentee disavows the full scope of a claim term either in the specification or during prosecution.' ”

The claim construction issues were fact-specific. In summary, the court discounted Sanofi's arguments as failing to meet either circumstance that would justify narrowing the claims.

Sanofi did not dispute that, under the now affirmed construction, Claim 5 of the '561 patent was obvious in light of the prior art including the GV and Vidal references. Sanofi also contested the lower court's similar judgment as to Claim 7 of the '512 patent, but the appeals court ruled that the company failed to rebut a specific finding that rendered the claim obvious irrespective of its other arguments.

The court therefore affirmed the obviousness judgments as to both patents.

Inequitable Conduct Under Heightened Standards.

As to inequitable conduct, the court said:  

In this case, although the district court did not have the benefit of our Therasense opinion when it rendered its inequitable conduct decision, the court nevertheless found that the withheld references were but-for material to patentability and made distinct intent and materiality findings rather than employing the now-abrogated sliding scale approach. Consequently, as set forth below, we conclude that the court's inequitable conduct determination withstands even the more rigorous standard adopted in Therasense.  


The court's decision on materiality flowed directly from its conclusion about the importance of the GV and Vidal references. “Because such references are necessarily material to patentability, the district court did not err in finding that the materiality requirement was established.”

Sanofi's arguments were focused instead on the intent prong. First, the company argued that Fabre had an explanation for why he withheld the Vidal reference: he contended that tests based on that reference failed. Accordingly, “intent to deceive the PTO” was not, Sanofi said, “the single most reasonable inference that could be drawn” from the decision to withhold.

However, the court looked at other testimony and evidence highlighting the importance of the solution, disclosed in Vidal, to the patented invention. The court thus agreed with the district court's judgment that the explanation, and Fabre, lacked credibility. A similar combination of testimony and evidence also showed Fabre lacked credibility with respect to withholding the GV reference, the court concluded.

In its final comment, the court indicated that, while it was deferring to the lower court's judgment, it was doing so because of the additional evidence and not only because of Fabre's testimony.

“Thus, contrary to Sanofi's contention, in concluding that Fabre acted with a specific intent to deceive the PTO, the district court did not rely solely on its finding that Fabre was not credible but instead viewed Fabre's testimony in light of the other evidence to reach its intent conclusion,” the court said.

It therefore ruled that the district court's finding was not clearly erroneous and affirmed the decision that the two patents were unenforceable for inequitable conduct.

Judges Richard Linn and Timothy B. Dyk joined the opinion.

George F. Pappas of Covington & Burling, Washington, D.C., represented Sanofi. Hospira was represented by James F. Hurst of Winston & Strawn, Chicago. Richard T. Ruzich of Duane Morris, Washington, D.C., represented Apotex.

By Tony Dutra  

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