California County Sues Polymaker Over Alleged Ghost-Gun Marketing

San Diego County has sued 3D-printing filament maker Polymaker, alleging it marketed ordinary PLA filament to the ghost-gun community as material for making firearm frames and receivers, which California law regulates as precursor parts. The county seeks profits, civil penalties and an injunction; the complaint points to Polymaker’s sponsorship and hiring of 3D-printing creator Sean Aranda, who had been banned from YouTube over firearm-policy violations, as evidence the company cultivated that audience. Filament itself is legal, and the claims are allegations; Polymaker did not respond to a request for comment reported by the Los Angeles Times. The suit comes amid broader California efforts to curb untraceable firearms, including a separate case over an online library of gun-design files and a new law that could eventually require safeguards in some newly sold 3D printers, contingent on industry standards. California officials say ghost guns are increasingly recovered, though reporting notes it is unclear how many are printed from scratch rather than assembled from kits.