Firearm microstamping, ballistic imprinting and ballistic engraving are all names given to a controversial[1] technology that has been developed with the goal of aiding in ballistics identification; it involves the use of laser technology to engrave a microscopic marking onto the tip of the firing pin and onto the breech face of a firearm. When the firearm is fired, these etchings are transferred to the primer by the firing pin and to the cartridge case by the breech face, using the pressure created when a round is fired. After the spent cartridges are ejected, these microscopic markings are imprinted on the cartridges, which can then be recovered by police and examined by forensic ballistics experts to obtain information to be used to trace the firearm through its life to the registered owner.[2] This technology was to be required in California starting in 2010, however, it is on hold and law enforcement is specifically exempt.[3]