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District Court Excludes 15 Prior Art References Not Disclosed in Invalidity Contentions

In this patent infringement action, Plaintiffs filed motions in limine to exclude 15 prior art references that defendants intend to use to show the state of the art pertinent to the patents-in-suit. Defendants included the 15 references on a recent notice, but the references were not included on defendants’ third (and final) amended invalidity contentions.

As explained by the district court, “Defendants intone the wearying refrain that granting the motion would constitute ‘reversible error,’ because they are absolutely entitled to show the state of the art. Defendants are correct that the obviousness analysis is expansive and flexible, and that references like the ones at issue now might be relevant to show what was generally known in the art at the time of the invention. But defendants miss the point, which is not whether the 15 references are relevant. The issue is whether the 15 references were properly disclosed in this case.”

The district court further explained that the references were not properly disclosed in the case. “I will accept defendants’ assertion that the 15 references were disclosed in Shenoi’s January 16, 2015, report (although disclosing a patent by a Bates number is a questionable practice, and defendants are a bit foggy about whether all the ‘disputed publications’ were in Shenoi’s report). But the problem is that after disclosing the Shenoi report, defendants sought to amend their invalidity contentions to, among other reasons, ‘[r]educe the number of prior art references relied upon and refine the claim charts for the ‘398 Patent.'”

The district court granted the motion and “plaintiffs relied on it, and now defendants are stuck with their Third Amended Invalidity Contentions. Dkt. 106, Ex. 3. Defendants argue that the 15 references are ‘state-of-the-art background references’ that did not have to be disclosed in their invalidity contentions.”

The district court then rejected the argument that these references could be included now as “state-of-the-art background references.” “Defendants seem to think that under 35 U.S.C. § 282(c), they can put in whatever they want for ‘state-of-the-art background references’ so long as they are disclosed in writing 30 days before trial. But § 282 does not trump this court’s orders requiring earlier disclosure of invalidity contentions.”

Accordingly, the district court ordered the additional prior art references excluded.

Ultratec, Inc. v. Sorenson Communications, Inc., Case No. 14-cv-66-jpd (W.D. Wisc. Sept. 22, 2015)

The authors of are patent trial lawyers at Jeffer Mangels Butler & Mitchell LLP. For more information about this case, contact Stan Gibson at 310.201.3548 or