Original jurisdiction: exclusive authority over intergovernmental disputes, subject to pre-constitutional treaty exclusions and legal right questions. Article 131 vests exclusive original jurisdiction in the Supreme Court over disputes between the Union and States, between the Union (with or without States) and other States, and between States where the dispute involves a question on which the existence or extent of a legal right depends; this jurisdiction is subject to a proviso excluding disputes arising from pre constitutional treaties, agreements, sanads or similar instruments that continue in operation or expressly preclude such jurisdiction.