Published on:

Failure to Disclose Expert on Timely Basis Justifies Exclusion Before Markman Hearing

In this patent infringement action, the defendant moved to exclude plaintiff’s expert witness on the basis that the expert was not disclosed on a timely basis. The plaintiff disclosed the witness on November 4, 2011, as an expert to testify as to “the molecular weigh characterization of polymers” in a claim construction hearing scheduled for November 9, 2011. The deadline for identifying witnesses to give testimony relevant to claim construction expired in July 2011.

In analyzing whether there was surprise as to the expert testimony, the district court began by noting that “[t]o name a witness so far beyond the deadline set by the scheduling order would require a strong justification.” The district court found that “[t]he issue of how molecular weight of a polymer should be measured was clearly identified as an issue for claim construction in the parties’ joint claim construction statement.” From this joint claim construction statement, the district court determined that it was established that plaintiff had notice of “differences as to how the molecular weight of a polymer was measured well before July 29, 2011.” The district court also noted that plaintiff did not suggest otherwise.

The district court also found that defendant timely disclosed an intent to rely on expert testimony on this point and that plaintiff did not. The plaintiff also acknowledged in its opening claim construction brief that it understood that defendant was relying upon expert witness testimony stating that it did not believe such evidence was necessary but that if the district court deemed it appropriate it would request to be allowed to submit its own expert and to depose the defendant’s expert. Nonetheless, plaintiff did not move for relief from the expert witness deadline, nor did it mention an expert in its responsive claim construction brief.

Defendant did in fact rely extensively on expert testimony in its opening claim construction brief. The defendant also stated in its reply brief that the plaintiff had not sought the deposition of the expert and that it would resist any effort to do after the expert deadline had passed. Thus, the district court found that there was no surprise to the plaintiff.

The district court also rejected plaintiff’s argument that the defendant had changed its joint claim construction position when its submitted its expert declaration. The district court found that there was no shift in the defense position that would justify naming a belated expert.

Finally, the district court analyzed the late date at which the plaintiff sought leave to name an expert witness, finding the delay unreasonable. “It was not until November 4, 2011, virtually on the eve of the claim construction hearing, that plaintiff gave notice that it intended to offer an expert witness. The plaintiff claimed that it was timely because it served an expert report on the defendant that day and would make the expert available for a deposition prior to the November 9, 2011 hearing. No other explanation was provided.

Based on these facts, the district court concluded that “the court can find no justification for allowing Plaintiff to name an expert witness on claim construction long after the deadline for doing so has passed and virtually on the eve of the claim construction hearing.” Accordingly, the plaintiff’s expert was barred from the claim construction hearing.

* * *

The obviously lengthy delay in attempting to come forward with an expert doomed the plaintiff’s hope of obtaining relief from the district court in this case. This not surprising result does show the need to promptly address any issues of belated experts–and the faster the better–so that one can show the district court diligence and also eliminate prejudice to the opposing party.

Pure Fishing, Inc. v. Normark Corporation, Case No. 3:10-cv-2140-CMC (D. S.Car. Nov. 7, 2011)

The authors of are patent trial lawyers at Jeffer Mangels Butler & Mitchell LLP. We represent inventors, patent owners and technology companies in patent licensing and litigation. Whether pursuing patent violations or defending infringement claims, we are aggressive and effective advocates for our clients. For more information contact Stan Gibson at 310.201.3548 or