* Corporations not liable for rights violations -court
* Dissenting opinion calls it blow to international law
* Case involves Nigerians executed over 1990s protests (Adds Alien Tort expert says strong dissent suggests further appeal likely)
By Grant McCool
NEW YORK, Sept 17 (Reuters) – A U.S. Appeals Court on Friday dismissed a case against Royal Dutch Shell Plc (RDSa.L) in which the oil company was accused of helping Nigerian authorities violently suppress protests against oil exploration in the 1990s.
Judges in the U.S. Court of Appeals for the 2nd Circuit in New York ruled that until the Supreme Court deemed otherwise, corporations could not be held liable in U.S. courts for violations of international human rights law.