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Replacement Technical Expert Does Not Justify Amendment of Invalidity Contentions

In this patent infringement action, Defendants moved to amend their invalidity contentions and justified the amendment based, in part, on the replacement of its technical expert.

Defendants asserted that its “replacement technical expert (engaged in December 2019 following the passing of prior expert Thomas Gafford) completed an independent review of the current contentions in January 2020 and concluded that, in light of the Court’s rulings on claim construction and ICM’s amended infringement contentions, these additional references would support his explanation why ICM’s doctrine of equivalents theory sweeps in the prior art.”  Defendants also argued that plaintiffs will not be prejudiced by these amendments because the three additional references are “modest” and “originate from the same technical field as those previously charted references;” and because “there [are] still several months before ICM’s June 1, 2020 deadline to respond, giving its technical expert ample time to consider them.”

The court disagreed with this argument, reasoning that “[t]he fact that defendants’ replacement expert found additional prior art and publications that he deemed relevant to the validity of the `645 patent provided no justification for why the defendants or their prior expert did not marshal the same evidence from at least 25 years ago in a more timely fashion.2 The defendants may not exploit the need to replace a deceased expert as an excuse to belatedly make significant changes to their invalidity theories. See, e.g., Apple v. Samsung Elecs. Co., No. C 11-1846, 2012 U.S. Dist. LEXIS 190470, at *61-65 (N.D. Cal. June 27, 2012) (striking numerous expert opinions of invalidity based on theories not previously disclosed in the defendant’s invalidity contentions); Chemfree Corp. v. J. Walter, Inc., 2008 U.S. Dist. LEXIS 93376, at *13-16 (N.D. Ga. Aug. 26, 2008) (denying leave to amend invalidity contentions to incorporate input from a technical expert where the original invalidity contentions were prepared without expert consultation).”

Plaintiffs also argued that they would be prejudiced by the amendment, explaining “that their strategy in planning and conducting discovery and working with their experts since mid-2018, as well as their earlier positions with respect to claims construction and summary judgment motions were strongly influenced by the defendants’ prior invalidity contentions.”

Based on this argument, the court found that “Plaintiffs persuasively demonstrate that they would be significantly prejudiced by defendants’ belated reliance on new prior art as a basis for their invalidity defenses. See, e.g., Mass Engineered Design, Inc. v. Ergotron, Inc., 250 F.R.D. at 287 (finding amendments to invalidity contentions would be “highly prejudicial” where “the additional prior art references may give rise to new claim construction issues”); L.C. Eldridge Sales Co. v. Azen Mfg. Pte., No. 6:11-cv-599, 2013 U.S. Dist. LEXIS 186309, at *16-17 (E.D. Tex. Oct. 11, 2013) (plaintiff would be prejudiced by proposed amendment of invalidity contentions because “[d]efendants simply have delayed too long to assert prior art that is listed in the patent in suit”); Chemfree Corp. v. J. Walter, Inc., 2008 U.S. Dist. LEXIS 93376, at *15 (rejecting the defense argument that plaintiff would not be prejudiced by allowing them to belatedly include additional prior art references in their invalidity contentions; “[i]f the Court were to accept Defendants’ . . . argument, parties would always be permitted to explain their invalidity contentions at the eleventh hour[,]” which would cut against the express purpose of the Patent Local Rules, which seek to “facilitate the speedy, fair and efficient resolution of patent disputes”).

Accordingly, the court denied Defendants’ motion to amend the invalidity contentions.

ICM Controls Corp. v. Honeywell Int’l, Inc., Case No. 5:12-CV-1766 (LEK/ATB) (N.D.N.Y. April 3, 2020)

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