AB2047 requires every 3D printer sold in California to run a DOJ state-certified "detection algorithm" - a technology that can not reliably exist. If passed, it would pull a tool used in thousands of schools, libraries, labs, and small businesses out from under our communities. This page is a plain-language guide you can share with your school board, PTA, or neighbor.
The bill cleared the full Assembly and has moved to the State Senate, where it goes first to the Judiciary and Public Safety committees. These members decide whether AB2047 advances - so these are exactly the people who need to hear from you now. Below is every member of both committees, with a direct phone line and email for each.
One email can reach every committee office plus the legislative staff who handle these bills. Copy the full list, paste it into the BCC field so offices don't see each other's addresses, and send a single message.
Suggested subject: Please vote NO on AB 2047. Tip: paste into BCC, not To.
A ringing phone in a Capitol office is hard to ignore - calls often carry more weight than email. No script needed: give your name, say you're a Californian, and urge a NO vote on AB 2047. Tap any number to call that office directly.
Scroll for the full list. Anna Caballero and Scott Wiener sit on both committees, so the email list above counts each of them once.
Personal letters from real Californians carry far more weight than form letters. Pick the points that matter to you and tell them why, in your voice:
Legislators weigh messages from the people they represent most of all - so if you live in California, your own Senator and Assembly Member need to hear from you. But every informed voice adds to the pressure, in California and beyond. Each of these takes five minutes or less. Do one today. Do all three this week.
Find your own State Senator and Assembly Member, and tell them to oppose AB2047. Representatives listen hardest to the constituents they answer to - and the more informed Californians who speak up, the louder that message lands. Phone calls beat emails. Two minutes, big impact.
Add your name on Change.org - Stop AB 2047: Protect Access to 3D Printers in California.
AB2047 rests on two foundations that cannot bear its weight: the legal foundation conflicts with established First Amendment law, and the technical foundation assumes capabilities that do not reliably exist.
CAD files and source code are protected expression; mandatory pre-review is a textbook prior restraint.
Forcing manufacturers to attest to contested algorithm output is compelled speech on a public concern.
Shapes shared between firearm parts and countless legitimate objects give no clear notice of prohibited conduct.
The bill sweeps in general-purpose hardware used overwhelmingly for lawful purposes.
A state-specific approved list for interstate hardware raises serious Dormant Commerce Clause issues.
Federal law already covers firearm manufacture, including via additive manufacturing.
Delegation, due process, Fourth Amendment telemetry, and state constitutional issues.
A rifled barrel is a grooved cylinder. So are industrial screws, optical mounts, and thousands of other parts.
Rotation, scaling, splitting a model into parts, or re-exporting defeats shape-based detection - without losing function.
By the time a printer sees G-code, shape context is gone. Reconstructing a "firearm" at print time is intractable.
Marlin, Klipper, and RepRap firmware can be flashed in minutes. Software-level "blocks" are simply removable.
There is no authoritative dataset of "firearm blueprints" - and the set grows adversarially.
Research on shape-based detection consistently shows error rates incompatible with general-purpose use.
Remote-print workflows, procedural generation, encrypted slicer output, multi-material composites, and more.
AB2047 cleared the Assembly's Public Safety, Judiciary, and Appropriations committees, survived the Suspense File, and has now passed the full Assembly floor with 33 amendments. It moves next to the State Senate, where it heads first to the Judiciary and Public Safety committees - the stage where your voice matters most right now. Take action now →
AB2047 is introduced in the California State Assembly, framed as a public safety measure targeting 3D-printed firearms.
The bill cleared the Assembly Public Safety Committee and was advanced for further review.
The bill cleared the Assembly Judiciary Committee and was advanced to Appropriations.
The bill cleared the Assembly Appropriations Committee, was placed in the Suspense File, and has now been released with 33 amendments and sent to the floor.
The full Assembly voted to pass the amended bill, sending it across to the State Senate for the second half of the process.
The bill now goes to the Senate's Judiciary and Public Safety committees. These members decide whether it advances - so they are exactly who needs to hear from you today. Email the Senate →
If it clears committee, the full Senate votes on the bill.
The Governor's signature or veto. The bill can be stopped at any stage.
Coverage of AB2047 and the maker community's response from across the tech press.

"California's AB2047 is one of the most troubling pieces of 3D printing legislation ever proposed." A profile of David Tobin's push to defeat the bill before the Assembly floor vote.

Experts warn that “safety algorithms” are a death sentence for makerspaces, schools, and innovation - with $10.5B in sunk costs and 1.5M California children using 3D printing today.