Defense Distributed Unveils Tool to Bypass Proposed 3D Printer Firearm Bans

Cody Wilson, the Austin, Texas-based founder of Defense Distributed who created the first fully 3D-printed firearm in 2013, has introduced a software tool aimed at neutralizing proposed legislation that requires 3D printers to block weapon manufacturing. Dubbed "Hochulization," the utility is named as a direct jab at New York Governor Kathy Hochul, who recently enacted the nation's first law requiring print-blocking software on new 3D printers sold in the state. Wilson characterized the tool as a defensive measure against state digital surveillance, as first reported by The Verge.

Defense Distributed operates DEFCAD, an online repository hosting over 200,000 design files for firearms and components such as suppressors. Typical print-blocking mechanisms rely on identifying restricted designs by generating a unique cryptographic string, known as a hash, for each file using an algorithm. The Hochulization tool appends a small series of extra bytes to a file, altering its unique hash value without changing the shape or mechanical function of the final printed object. Wilson stated he plans to apply this alteration across all 3D files hosted on DEFCAD by default and release the utility as open-source software.

The development comes as state lawmakers push to halt the proliferation of untraceable, home-manufactured firearms. New York included its software mandate in its fiscal year 2027 budget to curb the production of ghost guns, which have been linked to high-profile violent incidents such as the shooting of UnitedHealthcare CEO Brian Thompson. Meanwhile, California legislators are advancing Assembly Bill 2047, introduced by Assemblymember Rebecca Bauer-Kahan, which would ban the sale of 3D printers lacking approved blocking mechanisms by December 2029. Neither statutory text outlines specific software standards, leaving implementation details to appointed technical working groups.

Beyond simple hash matching, researchers and software vendors are developing artificial intelligence models that analyze physical file geometry to spot gun components. Wilson claimed his team built an internal classifier modeled on systems from vendors like Spain-based Print&Go, which is advising state lawmakers. According to Wilson, his team successfully bypassed their own AI system by altering mesh representations or adding unused geometry to files. He added that their test detection model yielded a 30 percent false positive rate, highlighting operational challenges associated with predictive spatial analysis.

Technical experts acknowledge that hash-scrambling tools can neutralize simple database checks, though basic detection systems may still serve a regulatory purpose. Solomon Diamond, an associate professor of engineering at Dartmouth College, told The Verge that while Hochulization effectively defeats hash identification, mandatory checks create friction that deters non-technical users. Law enforcement data indicates a sharp rise in printed weapons; the New York Police Department confiscated 109 3D-printed firearms in 2024, up from just one in 2021, mirroring increases reported by gun policy groups across 20 other U.S. cities.

Opposition to mandated hardware scanning extends beyond gun rights advocates to include digital rights groups, hobbyists, and legal scholars. Critics express concern that requiring continuous file inspection introduces broad digital surveillance and risks misidentifying benign consumer items as contraband, while creating infrastructure that corporations could exploit for intellectual property enforcement. Wilson previously faced federal action in 2013 when the U.S. Department of State cited export controls to force the removal of his original blueprints, sparking ongoing constitutional litigation over whether computer code represents protected speech under the First Amendment.