In an action to recover damages for personal injuries, etc., the third-party defendant appeals, as limited by its brief, from so much of an order of the Supreme Court, Westchester County (Daronco, J.), dated April 1, 1982, as denied its motion to dismiss the third-party complaint. Order reversed, insofar as appealed from, on the law, with $50 costs and disbursements, motion granted, and third-party complaint dismissed on the merits. The main action was instituted to recover damages for personal injuries, etc. The defendants in the main action instituted a third-party action against the appellant. That third-party action was dismissed upon appellant's motion for summary judgment after the defendants third-party plaintiffs were precluded from offering evidence to support their claim due to their failure to timely serve a bill of particulars. Thereafter the defendants third-party plaintiffs commenced a new third-party action against appellant on the same cause of action. In our opinion, "the unappealed grant of summary judgment in the prior action was a judgment on the merits of the plaintiffs' claims, and is therefore entitled to res judicata effect" ( Barrett v Kasco Constr. Co., 84 A.D.2d 555, 556, affd 56 N.Y.2d 830; see, also, Eidelberg v Zellermayer, 5 A.D.2d 658, affd 6 N.Y.2d 815). Mollen, P.J., Damiani, Titone and Mangano, JJ., concur.