While unloading oil to Hawai’i via an underwater pipeline, an Exxon Company, U.S.A. (plaintiff) oil tanker was moored to a Single Point Mooring System (SPM) owned and manufactured by Sofec, Inc. (defendant). During a storm, Exxon’s ship broke loose from the SPM. While trying to maneuver the ship clear of the broken oil hoses, the ship’s captain, Kevin Coyne, made a number of decisions that eventually resulted in the ship striking coral and spilling oil into the ocean. Exxon brought suit in admiralty against Sofec in the United States District Court for the District of Hawai’i. The district court found that Coyne’s negligence was the superseding and sole proximate cause of the harm and entered judgment in favor of Sofec. Exxon appealed. The United States Court of Appeals for the Ninth Circuit affirmed. The United States Supreme Court granted certiorari.