California makes 3D printer makers prepare for firearm-blocking rules

The law only takes effect if a relevant ASTM standard appears, so its impact may stay limited for now.

California has turned a bill into law that would require 3D printer makers to add firearm-blocking tech, but only after ASTM International publishes or adopts a relevant standard. For developers and hardware companies, the key detail is that existing printers are exempt, and the law regulates future sales and transfers rather than ownership or use. The California Department of Justice must look for such a standard every quarter starting no later than July 1, 2027, and stop checking after July 1, 2029 if none exists. That means the rule’s practical impact depends on a standard that may never arrive, which could delay or prevent implementation. The move makes California the second state with such restrictions, after New York, while Colorado and Washington state are considering similar bills.