CALIFORNIA TAKES AIM AT 3D-PRINTED FIREARMS: NEW LAW REQUIRES FIREARM-BLOCKING TECHNOLOGY
October 22, 2026 – California Governor Gavin Newsom recently signed Assembly Bill 2047, the California Firearm Printing Prevention Act, establishing a new regulatory framework intended to prevent the manufacture of firearms and machine gun conversion devices using three-dimensional (3D) printers. The legislation, codified at California Civil Code §§ 3273.631–3273.634, represents a significant expansion of firearms regulation by imposing prospective requirements on manufacturers of general-purpose 3D printing equipment.
Overview of the California Firearm Printing Prevention Act
AB 2047 prohibits the sale or transfer for consideration of 3D printers in California unless they incorporate technology capable of identifying and blocking digital files designed to produce firearms or machine gun conversion devices. The definition of a “three-dimensional printer” means “a computer-aided manufacturing device capable of producing a three-dimensional object from a three-dimensional digital model through an additive manufacturing process that involves the layering of two-dimensional cross sections formed of a resin or similar material that are fused together to form a three-dimensional object,” which does not include a CNC machine.
The legislation defines “firearm blocking technology” as integrated hardware, firmware, or other technological measures that prevent a printer from proceeding with a print job unless the underlying digital file has been evaluated by a firearm-blueprint detection algorithm and determined not to produce a prohibited item. Notably, the law’s broad definition potentially encompasses consumer and industrial 3D printers, although it expressly exempts printers used exclusively to manufacture props for the entertainment industry. However, the legislation provides no exemption for a Federal Firearms Licensee with a manufacturing license.
When Will the Requirements Take Effect?
Although the legislation becomes effective January 1, 2027, its principal restrictions will not take effect immediately. Beginning no later than July 1, 2027, the California Department of Justice (DOJ) must periodically determine whether ASTM International has published industry standards for firearm-blocking technology. If ASTM publishes applicable standards and the DOJ determines that compliance is technologically feasible, the agency must issue implementing guidance or regulations within 24 months. Manufacturers would then have an additional year before the sales restrictions become operative. If no applicable ASTM standards exist by July 1, 2029, the DOJ is relieved of its obligation to continue evaluating whether such standards have been developed. Consequently, the law’s practical implementation remains contingent upon the development of workable detection technology and subsequent regulatory action.
Technological Challenges Create An Uncertain Landscape For Feasibility and Enforcement
This legislation presents significant technological and regulatory challenges. Unlike traditional firearms regulations governing the manufacture, distribution, or possession of completed firearms, AB 2047 seeks to prevent firearm production by regulating the equipment used in the manufacturing process. One central question is whether detection algorithms can reliably distinguish firearm components from other products. Many firearm components share geometric characteristics with ordinary mechanical parts, creating the possibility of false positives. Conversely, modifying digital designs or dividing components into multiple printing files could potentially undermine detection systems. For manufacturers and distributors of 3D printers, the law creates prospective compliance obligations that could require changes to printer software, firmware, product design, and distribution practices.
California’s new legislation reflects an emerging regulatory approach that targets the technology capable of producing firearms, rather than firearms themselves. Whether that approach proves effective will depend on the development of reliable detection technology and the state’s ability to implement enforceable standards. For the firearms industry, AB 2047 warrants attention because it establishes a model of regulating the equipment used to manufacture firearms that other states could follow.
Renzulli Law Firm, LLP will continue to monitor new and developing firearm related laws around the country. If you have questions regarding firearms-related legislation or regulation, please contact Christopher Renzulli.