Microstamping is a proprietary ballistics identification technology. Microscopic markings are engraved onto the tip of the firing pin and onto the breech face of a firearm with a laser. When the gun is fired, these etchings are transferred to the primer by the firing pin and to the cartridge case head by the breech face, using the pressure created when a round is fired. After being fired, if the cases are recovered by police, the microscopic markings imprinted on the cartridges can then be examined by forensic ballistics experts to help trace the firearm to the last registered owner. A California law requiring the use of microstamping technology in all new semiautomatic firearms sold in the state has attracted controversy. Legal jurisdictions in the United States California Microstamping legislation was passed in California AB 1471 and signed into law on October 14, 2007, but specifically exempts law enforcement. The law has generated controversy. This technology was to be required in California starting in 2010, but requirements in the law that the technology be available unencumbered by a patent put it on hold. Law enforcement agencies are specifically exempt. One group, the Calguns Foundation, paid a $555 fee to keep the patent active in order to delay implementation. On May 17, 2013, California Attorney General Kamala Harris announced that micro-stamping had cleared all technological and patenting hurdles and would be required on newly sold semiautomatics, effective immediately. However, handguns already approved for sale but lacking this technology may still be sold as long as they remain on the Roster of Not Unsafe Handguns. In January 2014, the two largest handgun manufacturers in the U.S., Smith & Wesson and Sturm, Ruger & Co., announced their intent to stop selling new semi-automatic handguns in California. They cited the microstamping law as their reason. Two trade groups, the National Shooting Sports Foundation (NSSF) and the Sporting Arms and Ammunition Manufacturers Institute (SAAMI), have filed a lawsuit seeking both declaratory and injunctive relief against what the groups perceive as an attempt to ban semi-automatic handguns in the state. In February 2015 a federal judge upheld the microstamping requirement, ruling that it does not violate the Second Amendment. On December 1, 2016, a California Appellate Court reversed the Fresno Superior Court’s dismissal of the NSSF and the SAAMI lawsuit seeking an injunction to block enforcement of the state’s ammunition microstamping law and remanded the case back