Gov. Jerry Brown has signed legislation requiring hobbyists who assemble homemade guns to apply for a serial number and submit to a background check.
The legislation signed Friday is aimed at cracking down on untraceable firearms known as "ghost guns."
By 2019, people who own or create homemade firearms will have to apply for a serial number from the California Department of Justice and permanently affix it to the weapon.
The bill, AB857, sponsored by Democratic Assemblyman Jim Cooper of Elk Grove, joins six other gun control measures that the Democratic governor signed earlier in the month. Those included bills requiring people to turn in high-capacity magazines and background checks for ammunition sales.