The People of the State of California, acting through Damon M. Brown, County Counsel for the County of San Diego, have sued 3D-printer filament maker Polymaker LLC. The complaint, dated October 5, 2026, and filed in San Diego Superior Court, treats selected Polymaker plastics as “firearm precursor parts.” According to the complaint, the company allegedly markets them to become the frame or receiver of a working gun. Those guns are what the filing calls “ghost guns”: unserialized firearms made outside the licensed manufacturing system.