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).”