A Letter From the Industry
The letter
🔍 Click to read full letter
Organizational Signatories10 organizations
PRUSA Research
Printed Solid
MAKE Magazine
Maker Faire
West3D
Nikko Industries
VORON Design
3D Printing Nerd
Cocoa Press
Greengate3D
Individual Signatories7 individuals
Dr. Adrian Bowyer
Josef Prusa
Dale Dougherty
Maksim Zolin
Joel Telling
Anne Pauley
Clayton Parker (Uncle Jessy)
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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.
At a glance
What's at stake in California
K-12, CTE, Summer & After School programs
Students who depend on access
1.5M+
Small & Large business, labs, manufacturers
California operations affected
30,000+
Engineering, innovation & curriculum built in CA
Investment at risk in the state
$10.5B
1
Email every committee member
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.
2
Better yet, call their offices
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.
Judiciary Committee13 members · main line (916) 651-4113
Roger NielloR-06Vice-Chair
Anna CaballeroD-14Both committees
Suzette Martinez ValladaresR-23
Scott WienerD-11Both committees
Public Safety Committee6 members · main line (916) 651-4118
Kelly SeyartoR-32Vice-Chair
Anna CaballeroD-14Both committees
Scott WienerD-11Both committees
Scroll for the full list. Anna Caballero and Scott Wiener sit on both committees, so the email list above counts each of them once.
3
Write in your own words - here are the points that matter
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:
- The bill does not make anyone safer.
- The bill was rushed and now contradicts itself - after 33 amendments, its manufacturer mandate points to certification rules the same amendment deleted.
- The required technology is not possible - 3D printers read code, not intent; they cannot tell what a shape is for.
- The bill requires software that, if it could exist, would violate the First Amendment.
- It disrupts education at every level - K-12, CTE, libraries, community colleges, and universities.
- It breaks open-source 3D printing, which most classroom printers rely on, by demanding open firmware be as locked-down as proprietary firmware.
- California small businesses bear the burden - they must source or build firearm-blocking software that does not exist just to keep selling printers.
- The penalties hit the wrong people - the $25,000-per-violation fines fall on schools, makers, and small businesses, while bad actors route around the law.
- The exemptions are undefined - the bill exempts printers sold "exclusively" to entertainment studios, but no printer is built for one industry, leaving makers and cosplayers out.
Engage
Things you can do today.
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.
Why it doesn't work
What the bill can't solve.
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.
12
Legal Violations
Constitutional & statutory concerns
01
Prior restraint on protected speech
CAD files and source code are protected expression; mandatory pre-review is a textbook prior restraint.
02
Compelled speech
Forcing manufacturers to attest to contested algorithm output is compelled speech on a public concern.
03
Vagueness in "blueprint"
Shapes shared between firearm parts and countless legitimate objects give no clear notice of prohibited conduct.
04
Overbreadth
The bill sweeps in general-purpose hardware used overwhelmingly for lawful purposes.
05
Commerce Clause concerns
A state-specific approved list for interstate hardware raises serious Dormant Commerce Clause issues.
06
Federal preemption
Federal law already covers firearm manufacture, including via additive manufacturing.
+
Six more concerns detailed
Delegation, due process, Fourth Amendment telemetry, and state constitutional issues.
12+
Technical Failures
Why the tech can't actually work
01
Geometry isn't uniquely a firearm
A rifled barrel is a grooved cylinder. So are industrial screws, optical mounts, and thousands of other parts.
02
Trivial workarounds
Rotation, scaling, splitting a model into parts, or re-exporting defeats shape-based detection - without losing function.
03
G-code is the wrong layer
By the time a printer sees G-code, shape context is gone. Reconstructing a "firearm" at print time is intractable.
04
Firmware is open
Marlin, Klipper, and RepRap firmware can be flashed in minutes. Software-level "blocks" are simply removable.
05
No ground-truth dataset
There is no authoritative dataset of "firearm blueprints" - and the set grows adversarially.
06
Published error rates are too high
Research on shape-based detection consistently shows error rates incompatible with general-purpose use.
+
Six more technical barriers
Remote-print workflows, procedural generation, encrypted slicer output, multi-material composites, and more.
Bill progress
Where it stands right now.
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 →
FebruaryIntroduced
Bill Introduced Completed
AB2047 is introduced in the California State Assembly, framed as a public safety measure targeting 3D-printed firearms.
MarchPublic Safety
Passed Public Safety Committee Completed
The bill cleared the Assembly Public Safety Committee and was advanced for further review.
AprilJudiciary
Passed Judiciary Committee Completed
The bill cleared the Assembly Judiciary Committee and was advanced to Appropriations.
MayAppropriations
Appropriations & Suspense File Completed
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.
MayAssembly Floor
Passed the Assembly Floor Completed
The full Assembly voted to pass the amended bill, sending it across to the State Senate for the second half of the process.
NowSenate Committees
Senate Judiciary & Public Safety Active now
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 →
TBDSenate Floor
Senate Floor Vote Upcoming
If it clears committee, the full Senate votes on the bill.
TBDFinal
Governor's Desk Upcoming
The Governor's signature or veto. The bill can be stopped at any stage.
3D Printing Nerd
Watch the full breakdown.
Joel Telling (3D Printing Nerd) walks through AB2047, what it means for the maker community, and why the technical premise doesn't hold up.
In the news
The story is spreading.
Coverage of AB2047 and the maker community's response from across the tech press.