California law requires 3D printers to block firearm printing

Gov. Gavin Newsom signed a bill requiring 3D printer makers to add firearm-blocking technology once ASTM International publishes a standard. California is the second state after New York to impose such rules; existing printers are exempt from retrofitting.

• The requirement takes effect only after ASTM International publishes a standard
• California DOJ must check for the standard quarterly from July 1, 2027, to July 1, 2029
• Rules cover only the sale of new printers, not ownership or use
• Colorado and Washington state have similar bills in their legislatures