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Applicant's Prosecution Statements May Render Prior Art Highly Material For Inequitable Conduct Analysis

Client Alert | 1 min read | 10.07.08

In Praxair, Inc. v. Advanced Technology Materials, Inc. (No. 2007-1483; September 29, 2008), the Federal Circuit affirms the district court's determination that one of the asserted patents was unenforceable due to inequitable conduct. Inequitable conduct requires both a finding of materiality and an intent to deceive. The district court concluded that certain prior art withheld by the applicant from the United States Patent & Trademark Office ("USPTO") was material to the patentability of the asserted patent. With respect to the "intent to deceive" prong of its inequitable conduct finding, the district court concluded that the withheld prior art was highly material in the context of four statements made to the USPTO during the course of prosecuting the asserted patent. These statements included blanket assertions about features that were purportedly missing from the prior art.

The Federal Circuit, in affirming the district court's finding of inequitable conduct, notes that the district court "did not conclude that the prior art [devices] were themselves highly material." Rather, the Federal Circuit acknowledged that it was the context in which the particular statements were made to the USPTO that caused the withheld prior art to become highly material. Thus, the materiality of withheld prior art, for purposes of determining an intent to deceive in connection with an inequitable conduct claim, may be a function of both the actual teachings of the withheld prior art, as well as any blanket statements made to the USPTO regarding allegedly missing features in the prior art.

In a separate opinion dissenting on the finding of inequitable conduct, Judge Lourie states that the "district court incorrectly conflated intent with materiality" when it relied on the materiality of the reference to demonstrate proof of deceptive intent. According to Judge Lourie, more is required than the materiality of a reference to prove deceptive intent, and thus inequitable conduct.

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