The asserted patent relates to using large DNA vectors to target and modify endogenous genes and chromosomal loci in eukaryotic cells and this technology may be used to modify genes in mice to develop antibodies for use in humans. Prior to issuance of the notice of allowance, a third-party submitted three references in the parent application. Regeneron failed to disclose the third-party submission and a fourth reference in the present application but disclosed them in every related application having the same specification. On appeal, the Federal Circuit concluded that the district court did not err in finding each of the withheld references but-for material and that it didn't abuse its discretion in drawing the adverse inference of specific intent based on discovery misconduct that obfuscated its prosecution misconduct.
In here dissent, Judge Newman complained that misconduct during litigation must not affect a finding of inequitable conduct and specific intent must be based on conduct during prosecution and should not be based on any adverse inference, particularly litigation misconduct.
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