IM-873X was an Imperial Star Galleon used as a freighter. Over a period of six years leading to the Battle of Yavin, the ship made regular trips to the Corva sector. In 0 ABY, a delay of eight days caused Alliance Intelligence to take notice. Extrapolating from its fuel capacity, the Rebels found a limited list of where it could have stopped, and it was estimated that its delay was caused to a trip to the Stylar Nebula, where it had been suspected the Empire was conducting secret military research. The data, coupled with a hacked transmission mentioning Operation: Shell Cracker, caused the Intelligence to launch a mission to the site.