Maryland v. West Virginia, 217 U.S. 1 (1910), is a 9-to-0 ruling by the United States Supreme Court which held that the boundary between the American states of Maryland and West Virginia is the south bank of the North Branch Potomac River. The decision also affirmed criteria for adjudicating boundary disputes between states, which said that decisions should be based on the specific facts of the case, applying the principles of law and equity in such a way that least disturbs private rights and title to land.