Code black hole was an identifier code used by privateers and pirates during the Galactic Civil War. All starships in the galaxy had transponder codes imprinted in the sublight engine that identified the name of the ship, its owner and its type. The codes were registered by the Bureau of Ships and Services and were intended to identify ships involved in illegal activities. Pirates and privateers would make use of illegal technology to mask or alter the transponder codes to create double identities for their ships, using innocent codes for legitimate business and "pirate codes" when raiding. The pirate code, called "code black hole", identified the owner's alias and was intended to frighten the target ship's crew into surrendering. Rebel privateers used their own variant of code black hole, called "code quasar."