Order unanimously reversed, without costs, motions granted and action dismissed. Memorandum: In a medical malpractice action plaintiff served a summons on defendants, a hospital and two doctors, in June, 1972. Defendants replied by serving notices of appearance and demands for the complaint. However, no complaint was served during the next seven months. Defendant hospital then sent a letter to plaintiff's attorney requesting the complaint. Six months later, in July, 1973, the complaint was finally sent to defendants. Defendants refused to accept the complaint and instead brought this motion to dismiss the action for failure to prosecute pursuant to CPLR 3012 (subd [b]). It then became incumbent upon the plaintiff to show that the 13-month delay was excusable and that the claim was meritorious (McIntire Assoc. v Glens Falls Ins. Co., 41 A.D.2d 692; Sortino v Fisher, 20 A.D.2d 25). Although it appears that plaintiff may have a meritorious claim, the only contentions made to support the long delay in serving the complaint were the complexity of the litigation, the difficulty in investigating and interviewing witnesses and the inherent difficulties of medical malpractice actions. These factors constitute law office failure and as such are insufficient to excuse the delay (McIntire Assoc. v Glens Falls Ins. Co., 41 A.D.2d 692, supra; Sortino v Fisher, 20 A.D.2d 25, 29, supra).