Noncontiguous Shipping Competition Act This bill revises coastwise laws, commonly known as the Jones Act, that govern domestic transportation of merchandise or passengers by vessels. The Jones Act requires that vessels transporting merchandise or passengers between Puerto Rico and other U.S. ports be built in the United States, be at least 75% owned by U.S. citizens, and be mostly crewed by U.S. citizens. The bill exempts carriage on a route in noncontiguous trade from Jones Act requirements unless (1) at least three owners or operators of certain coastwise vessels regularly operate such a vessel on the route, (2) each of such owners or operators transports at least 20% of the volume of goods on that route, and (3) none of such owners or operators are under common ownership.