A controversy is not "between citizens of different states" so as to give jurisdiction to the federal courts unless all the persons on one side of it are citizens of different states from all the persons on the other side.
In a 158-word opinion the Court held that for federal diversity jurisdiction, under section 11 of the Judiciary Act of 1789, no party on one side of a suit may be a citizen of the same state as any party on the other side.[1] Therefore, when there are joint plaintiffsordefendants, jurisdiction must be established as to each party. That requirement remains acceptable in law as a matter of statutory interpretation, not constitutional command.[2]
^State Farm Fire & Casualty Co. v. Tashire, 386 U.S. 523, 530–31 (1967), saying of Strawbridge, "Chief Justice Marshall there purported to construe only 'The words of the act of Congress,' not the Constitution itself. And in a variety of contexts this Court and the lower courts have concluded that Article III poses no obstacle to the legislative extension of federal jurisdiction, founded on diversity, so long as any two adverse parties are not co-citizens."
