1
Call your own Senator first
Senators weigh calls from the people who can vote for them differently from everyone else's. If you live in California, start with the office that answers to you. It is one call, and it is the one that counts most.
Enter your address and it returns your district and office. Then find that Senator in the list and dial.
2
What to say when they pick up
You will reach a staffer, not the Senator. They are not there to argue with you - their job is to record your position. Short and polite beats long and heated every time.
"Hi, my name is [your name] and I'm a constituent in [your city]. I'm calling to ask the Senator to vote NO on AB 2047. [One sentence on why this matters to you.] Thank you for your time."
That is the whole call. If they ask for your ZIP code or address, give it - that is how the call gets counted. If you get voicemail, leave the same message; those are tallied too.
3
Then work down the whole list
A floor vote means every one of these 40 offices casts a vote on AB2047 - not just the ones on a committee. Calling beyond your own district is the most direct pressure available to you right now.
These are the Capitol offices in Sacramento. On a phone, tap any number to dial it. You do not have to do all 40. Do five today, five tomorrow.
Every California Senator's Capitol office40 offices
Sen. Grayson D-09Bill sponsor
Sen. Smallwood-Cuevas D-28
Scroll for the full list. Offices are staffed 9am to 5pm Pacific, Monday to Friday - calls placed during business hours reach a person. Outside those hours, leave a voicemail.
Outside the US? You are still welcome to call, and 3D printing is a global community - but a Californian's call carries the most weight here. The most useful thing you can do is send this page to someone who lives in the state.
If you have another thirty seconds, give them a reason.
Pick whichever one is true for you and say it in your own words. One real sentence from a real person carries further than a script read aloud.
- It does not make anyone safer. It regulates a tool, not a crime.
- The technology it mandates does not exist and cannot be built. Printers read code, not intent - they cannot tell what a shape is for.
- It disrupts education at every level: K-12, CTE, libraries, community colleges, and universities.
- It breaks open-source 3D printing, which most classroom printers depend on.
- It opens California businesses, schools, and families to civil lawsuits, forcing them to prove a negative to defend themselves.
- The $25,000-per-violation penalties hit the wrong people - schools, makers, and small businesses - while bad actors route around the law entirely.
- It costs the state real money: a new DOJ certification department and years of research into software experts say is impossible.
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)
California AB 2047 spends millions of taxpayer dollars, year after year, supporting mandated software that experts say can't be built, and that scans your data.
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
The bill, explained
What AB2047 actually does.
The bill sets up a new state regulatory regime for 3D printers, rolling out over six steps between today and 2029. Here's each one, in plain language.
1
By July 2027
California DOJ studies "blueprint detection"
The Department of Justice is directed to investigate firearm blueprint files and existing detection algorithms, and publish performance standards.
Why it matters The state is trying to define a technology that - by consensus in the research community - does not reliably exist yet.
2
By January 2028
DOJ begins certifying algorithms
Third-party vendors can submit their detection algorithms for state certification, and DOJ publishes guidance on "firearm blocking technology" to be installed on printers.
Why it matters The state picks winners. Every printer maker must license from a narrow, politically chosen set of vendors.
3
By July 2028
Manufacturers must submit attestations
Every company making or selling 3D printers in California must submit an attestation per make and model, confirming certified blocking tech is installed.
Why it matters Hobbyist-scale makers, open-source projects, and kit builders are effectively locked out - the paperwork itself is a barrier.
4
By September 2028
DOJ publishes the "approved list"
The state maintains a public list - updated quarterly - of 3D printer makes and models that have submitted valid attestations. If it's not on the list, it can't be sold here.
Why it matters A state permissions list for general-purpose computing hardware. Every firmware update re-triggers the process.
5
Starting March 2029
The sale ban takes effect
Sale or transfer of any 3D printer not equipped with certified blocking tech and not on the approved list is prohibited. Civil lawsuits may be filed against violators.
Why it matters California becomes the first state in the country to ban the sale of a category of general-purpose hardware based on theoretical misuse.
6
Ongoing
New criminal penalties
It becomes a crime to disable, uninstall, or circumvent the firearm blocking tech on a 3D printer with intent to manufacture firearms.
Why it matters The same modifications researchers, teachers, and hobbyists make today become criminal acts - based on "intent" judged after the fact.
The stakes
What Californians stand to lose.
3D printing is one of the most widely-adopted hands-on learning tools in California schools. AB2047 puts that infrastructure - and the businesses built around it - in the crosshairs.
1.5M+
Students who depend on access
K-12, CTE pathways, community colleges, and university labs
30,000+
California businesses affected
From dental labs to jewelry makers to Fortune 500 R&D
$10.5B
Sunk investment in the state
Hardware, training, curriculum, and program build-out
12
Constitutional concerns identified
First Amendment, due process, Commerce Clause, and more
Who it affects
The people who use 3D printers every day.
AB2047 targets the hardware, but the impact lands on students, teachers, makers, and small business owners using these tools for entirely legal, productive purposes.
🎓
Students & educators
Over 1.5M California students access 3D printing through school maker labs, CTE programs, and college engineering courses. Most school printers wouldn't qualify under AB2047's attestation regime.
K-12 · CTE · Higher Ed
🔧
Makers & small business
Prototype shops, dental labs, custom manufacturers, jewelers, medical device startups - every California small operation that depends on affordable, general-purpose printers.
30,000+ businesses
🧰
Open-source & hobbyists
RepRap, Voron, Klipper, and countless community-built printer designs cannot participate in a manufacturer-attestation system. They'd simply not be sold in California.
Community hardware
🔬
Researchers & engineers
Labs that modify firmware, experiment with extruders, or build next-gen additive manufacturing depend on hardware they can legally configure. Criminalizing circumvention chills real research.
Research & R&D
📚
Libraries & community spaces
Hundreds of California public libraries and community maker spaces offer free 3D printer access. Replacement on compliance grounds would gut those programs - disproportionately in low-income areas.
Public access
🏛️
Taxpayers
AB2047 creates a new DOJ certification regime, a quarterly-maintained list, and a civil enforcement mechanism - all paid for with California tax dollars, to solve a problem federal law already addresses.
State-mandated program
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 passed the full Assembly floor with 33 amendments. In the State Senate it has now cleared the Judiciary Committee (June 23), the Public Safety Committee (June 30), and the Appropriations Committee. Every committee is behind it. What remains is a vote of the full Senate floor, where all 40 Senators decide - and no date has been set. Call your Senators →
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.
June 23Senate Judiciary
Passed Senate Judiciary Committee Completed
The bill was heard by the Senate Judiciary Committee on June 23, cleared it, and advanced to the Senate Public Safety Committee.
June 30Senate Public Safety
Passed Senate Public Safety Committee Completed
The bill cleared the Senate Public Safety Committee on June 30 and now advances to the Senate Appropriations Committee.
AugustSenate Appropriations
Passed Senate Appropriations Committee Completed
After the summer recess the committee weighed what AB2047 would cost the state, and passed it. That was the last committee standing between the bill and a vote of the entire Senate.
NextSenate Floor
Senate Floor Vote Vote pending
All 40 State Senators vote on AB2047. No date has been set. Floor votes are scheduled with very little notice, so waiting for a date on the calendar means missing the window to be heard. Calling Senate offices now is the most useful thing anyone can do. Call your Senators →
TBDFinal
Governor's Desk Upcoming
If the Senate passes it, AB2047 goes to the Governor for a signature or a veto. The bill can be stopped at any stage.
Toolkit
Resources to share and use.
Print-ready handouts, letter templates, and talking points - built for schools, families, and neighborhood meetings.
Parent & teacher one-pager
A single-page handout explaining AB2047 in plain language - ready to bring to your next school board or PTA meeting.
1 pageDownload ↓
DOC
Legislator letter template
An editable letter opposing AB2047. Personalize one paragraph and send in under five minutes.
2 pagesDownload ↓
School board talking points
Bullet-point arguments tailored for school boards and district administrators concerned about CTE impact.
3 pagesDownload ↓
Full bill analysis
Section-by-section breakdown with annotations from lawyers, engineers, and policy experts.
32 pagesDownload ↓
ZIP
Social media kit
Friendly graphics sized for X, Instagram, LinkedIn, and TikTok - includes parent-focused copy options.
14 filesDownload ↓
Small business impact guide
Talking points for dental labs, jewelry makers, prototype shops, and other small businesses.
12 pagesDownload ↓
In the news
The story is spreading.
Coverage of AB2047 and the maker community's response from across the tech press.
Los Angeles Times July 19, 2026
California's push to ban technology used for 'ghost guns' finds unlikely foe in Hollywood
Hollywood's special-effects and prop shops, including Legacy Effects, line up against AB2047, warning that the same general-purpose 3D printers they depend on would be swept in - and that the bill's narrow exemption for printers "sold exclusively" to studios would not cover them.
3DPrint.com June 9, 2026
Why California's 3D Printer Bill Worries the Industry: David Tobin Says "It Regulates a Tool, Not the Crime"
"You're regulating a tool instead of the crime. The bigger concern is the precedent." David Tobin argues AB2047 misses the mark by mandating firearm-blocking tech in printers rather than enforcing existing law.
By Vanesa Listek → Read on 3DPrint.com
Fabbaloo May 15, 2026
David Tobin Is Fighting California's 3D Printer "Ghost Gun" Bill
"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.
→ Read on Fabbaloo
Tom's Hardware April 27, 2026
3D printing community organizes against California law that would restrict sales to state-approved models
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.
By Denise Bertacchi → Read on Tom's Hardware
On YouTube
Watch the full breakdown.
A growing series from the 3D Printing Nerd and the wider maker community: what AB2047 does, what it means for makers, schools, and businesses, and why its technical premise doesn't hold up.