Pennoyer Rule Law and Legal Definition

Pennoyer rule refers to the principle that a court may not issue a personal judgment against a defendant over which the court has no personal jurisdiction. This rule is based upon the case Pennoyer v. Neff.

It was observed in Pennoyer v. Neff, 95 U.S. 714 (U.S. 1878) that the authority of every tribunal is necessarily restricted by the territorial limits of the state in which it is established. Any attempt to exercise authority beyond those limits will be an illegitimate assumption of power, and be resisted as mere abuse.