“ In his petition for certiorari to this Court, Temple contends that it was error to label joint tortfeasors as indispensable parties under Rule 19 (b) and to dismiss the lawsuit with prejudice for failure to join those parties. We agree. Synthes does not deny that it, the doctor, and the hospital are potential joint tortfeasors. It has long been the rule that it is not necessary for all joint tortfeasors to be named as defendants in a single lawsuit. ”

“ After examining the factors set forth in Rule 19 (b) , we determined that the action could proceed without the policyholder; he therefore was not an indispensable party whose absence required dismissal of the suit. Id., at 116, 119, 88 S.Ct., at 741, 743.
Here, no inquiry under Rule 19 (b) is necessary, because the threshold requirements of Rule 19 (a) have not been satisfied. As potential joint tortfeasors with Synthes, Dr. LaRocca and the hospital were merely permissive parties. ”

“ National Screen Service Corp., 349 U.S. 322, 329-330, 75 S.Ct. 865, 869, 99 L.Ed. 1122 (1955) ; Bigelow v. Old Dominion Copper Mining & Smelting Co., 225 U.S. 111, 132, 32 S.Ct. 641, 644, 56 L.Ed. 1009 (1912) . See also Nottingham v. General American Communications Corp., 811 F.2d 873, 880 (CA5) (per curiam ) , cert. ”