Putianshi Lichengqu Zhengchangpai E-Commerce Co., Ltd. v. Shuangfeng County Shuangwei Electronic Technology Co., Ltd., No. 23 C 2650 (N.D. Ill. Sept. 19, 2025) (Alonso, J.).
Judge Alonso dismissed this declaratory judgment patent infringement case after finding that plaintiff’s Rule 30(b)(6) witness committed perjury during deposition. In this case involving design patents for silicon sleeve bamboo lids, plaintiff sought a declaratory judgment of invalidity and non-infringement of defendant’s D959,896 patent.
During the Rule 30(b)(6) deposition of plaintiff (the accused infringer), defendant patentholder showed the deponent nine screenshot exhibits of Amazon listings featuring tumblers with accused lids. When asked whether plaintiff was still selling these products, the deponent stated they had stopped selling all such lids. However, defendant’s counsel subsequently found several active listings on plaintiff’s Amazon store featuring identical lids.
The Court found the deponent’s testimony was willfully false, rejecting plaintiff’s “shifting and vacillating explanations” that the deponent was confused about which lids were being discussed. The Court noted that defense counsel’s questions clearly encompassed all lids shown during the deposition, and the deponent had unequivocally stated sales had stopped.
Significantly, the Court held that perjury about damages issues was material even though liability had not yet been established. The Court explained that litigants cannot “lie with impunity about damages issues merely because the Court might not reach them.”
Finding dismissal appropriate as a sanction, the Court emphasized that perjury “undermines the most basic foundations of our judicial system” and that no litigant should feel free to commit perjury hoping that “even if the lies are exposed, the rest of the case will progress unhindered.” Quoting Secrease v. W. & S. Life Ins. Co., 800 F.3d 397, 402 (7th Cir. 2015). The Court dismissed plaintiff’s claims with prejudice and defendant’s counterclaim without prejudice.