Section 282’s requirement that prior art be disclosed at least 30 days before trial does not eliminate other disclosure requirements under the Federal Rules of Civil Procedure; a patentee’s failure to explicitly challenge that the prior art contains a limitation is not a concession that the prior art includes that limitation.

The patentee brought an infringement action against a competitor. Two days before discovery closed, and more than 30 days before trial, the accused infringer located several drawings that predated the patents. The next day the accused infringer informed the patentee that the drawings may be anticipatory prior art, and that the drawings may be used at trial. At trial, the patentee moved to exclude the drawings because the accused infringer failed to supplement its response to an interrogatory seeking, on a claim-by-claim basis, all prior art that would be used to challenge validity. The accused infringer moved to sanction the patentee for failing to conduct an adequate pre-filing investigation. The district court denied the accused infringer’s motion for sanctions and excluded the drawings, and the patentee obtained a jury verdict in its favor. The accused infringer appealed, and the Federal Circuit affirmed. 

The court held that the district court did not abuse its discretion in excluding the drawings, which were not disclosed in the alleged infringer’s interrogatory response. The requirement to give 30 days prior notice of prior art under 35 U.S.C. § 282 does not eliminate an alleged infringer’s obligations under the Federal Rules of Civil Procedure. Although the alleged infringer had timely produced the documents to the patentee consistent with Section 282, the accused infringer had inadequately supplemented its interrogatory response in violation of Rule 26(e). Exclusion of the drawings was an appropriate sanction for this discovery violation.

The court also rejected the accused infringer’s argument that the patentee acquiesced to various characterizations of the prior art by the examiner in related patent applications. In one instance, the patentee amended a claim to include an additional limitation. This amendment did not constitute an admission that the prior art included all the previous limitations because “viewing an amendment as an admission that the initial claim was unpatentable requires more than the mere presence of a limitation.” Similarly, “[a] patent applicant is not presumed to have conceded the presence in the prior art of every claim limitation he had no reason to dispute.” 

A copy of the opinion can be found here