A defendant's appearance in an action is deemed to be the equivalent of personal service of a summons, and, in the absence of an objection to jurisdiction by way of a motion or answer, the appearance confers personal jurisdiction over that defendant. In addition to the formal appearances listed in CPLR 320(a), a defendant may appear informally by actively litigating the action before the court. Here, the defendant waived the defense of lack of personal jurisdiction by filing a notice of appearance and opposing the plaintiff's motion for leave to enter a default judgment against the defendant and for an order of reference without simultaneously asserting an affirmative objection to jurisdiction.
Bank of N.Y. Mellon v. Taylor, NY Slip Op 04119 (2d Dep't August 7, 2024)