AB 2047, California’s Firearm Printing Prevention Act, passed the Assembly on May 27. It heads to the Senate this summer.

The problem is real. 3D-printed ghost gun recoveries increased nearly 1,000% across 20 major cities over five years. Untraceable firearms manufactured in bedrooms and garages. Conversion devices that turn pistols into machine guns. This is not theoretical.

The solution: mandate that every consumer 3D printer sold in California include a firearm blueprint detection algorithm. The software scans every file β€” STL, CAD, geometric code β€” before the printer moves. If the algorithm flags the geometry as a firearm component, the print job is blocked. If the printer detects “suspicious printing patterns or geometries,” it reports to a DOJ-managed database.

The Department of Justice publishes performance standards by January 2028. Manufacturers submit attestation forms by July 2028. The DOJ publishes a roster of approved printers by September 2028. After March 1, 2029, selling a printer not on the roster is a civil violation. Up to $25,000 per sale.

Disabling the blocking software is a misdemeanor.

Using open-source firmware β€” the kind that runs in schools, hackerspaces, and research labs, the kind that made desktop 3D printing possible β€” is effectively criminalized unless it includes compliant censorship software.

Now the exemption list.

Licensed firearms manufacturers are exempt. The industry that makes guns professionally does not need to prove its printers can’t make guns.

Law enforcement is exempt.

Government contractors are exempt.

The entertainment industry receives a carveout for stagecraft and prop-making.

Schools do not.

Libraries do not.

Makerspaces do not.

A prop house making replica firearms for a Netflix production prints without DOJ oversight. A high school robotics team printing a bracket submits to algorithmic scanning and potential reporting to a state database.

The geometric problem is irreducible. The bill’s own supporting documentation acknowledges it: “A component used in a firearm may share geometric features with a hinge, tool housing, or other benign part.” A trigger guard and a cable guide share contours. A lower receiver and a tool housing share dimensions. Intent cannot be determined from geometry. The algorithm doesn’t know what you’re building. It knows what the shape looks like.

These are not the same thing.

The bill’s own language on accuracy: the standards “should account for false-positive and false-negative rates.” Not eliminate. Account for. A robotics student’s bracket gets flagged, and the flag goes to a DOJ database, and the standard that governs whether that flag was warranted says should account for the possibility that the bracket is a bracket.

The compliance paths: firmware-based blocking, proprietary slicer software that only accepts approved code, or handshake authentication systems. All three require the printer to evaluate files against a government-maintained standard before manufacturing. A manufacturing tool that asks permission before it manufactures.

The EFF notes that cloud-based scanning creates additional exposure: “scans meant to be ephemeral can be collected and surveilled.” Businesses prototyping parts risk intellectual property leaks through the reporting infrastructure. Your design goes through a DOJ database before it goes through quality control.

This is California’s second surveillance-infrastructure bill this session. AB 1856 β€” Signal 077 β€” built a three-layer pipeline for age verification: operating system, browser, website. That bill exempted open-source operating systems at one layer while the pipeline caught users at the next two. The exemption was real and irrelevant simultaneously.

AB 2047 uses the same architecture. Embed monitoring in the device. Report to a government database. Criminalize circumvention. Exempt the industries with lobbyists. Two bills. Two devices. Same session. Same state. Same blueprint.

The 1,000% increase is real. The violence is real. Saying so isn’t a concession β€” it’s the ground the criticism stands on. A solution that exempts the firearms industry, criminalizes open-source firmware, reports print files to the DOJ, and acknowledges its own false-positive rate is not a solution to gun violence. It is a surveillance architecture that borrowed gun violence’s urgency.

AB 1856 monitors what you view. AB 2047 monitors what you make.

The question isn’t what’s next. The question is what’s left.

// NEON BLOOD

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