; (2) Executive order; (3) proclamation of the President; or (4) proclamation of the Governor of the territory of Puerto Rico, shall remain the property of the United States. (c) Continental shelf The State of Puerto Rico shall have the exclusive right to explore, exploit, lease, possess, and use all seabed, natural, and mineral resources lying within three marine leagues (nine nautical miles) from its shore, as granted under section 8 of the Act of March 2, 1917 ( 48 U.S.C. 749