“The modern doctrine of pendent jurisdiction, as announced by the Supreme Court in United Mine Workers v. Gibbs (1966), is much broader…. Pendent jurisdiction, the Court said, existed whenever ‘the state and federal claims … derive from a common nucleus of operative fact,’ and when considerations of judicial economy dictate having a single trial.” David P. Currie, Federal Jurisdiction in a Nutshell 106 (3d ed. 1990).
common nucleus of operative fact test
common-nucleus-of-operative-fact test. The doctrine that a federal court will have pendent jurisdiction over state-law claims that arise from the same facts as the federal claims providing a basis for subject-matter jurisdiction. [Cases: Federal Courts 14.]