Artikel 19

1. A court before which proceedings to which a Contracting State is a party are instituted shall, at the request of one of the parties or, if its national law so permits, of its own motion, decline to proceed with the case or shall stay the proceedings if other proceedings between the same parties, based on the same facts and having the same purpose:
(a) are pending before a court of that Contracting State, and were the first to be instituted; or
(b) are pending before a court of any other Contracting State, were the first to be instituted and may result in a judgment to which the State party to the proceedings must give effect by virtue of Article 20 or Article 25.
2. Any Contracting State whose law gives the courts a discretion to decline to proceed with a case or to stay the proceedings in cases where proceedings between the same parties, based on the same facts and having the same purpose, are pending before a court of another Contracting State, may, by notification addressed to the Secretary General of the Council of Europe, declare that its courts shall not be bound by the provisions of paragraph 1.