Ghost Guns and Untraceable Firearms Act of 2023

This bill defines "ghost guns" as firearms (including frames and receivers) without a unique serial number from a licensed manufacturer or importer. It requires all new firearms to have a serial number engraved by a licensed maker and prohibits unlicensed individuals from manufacturing, selling, transferring, or possessing ghost guns after a one-year transition period (starting one year after enactment). The bill also bans unlicensed engraving of serial numbers on firearms and updates rules to ban undetectable firearms, with penalties including fines and up to 5 years in prison for repeat violations. These changes directly affect unlicensed gun builders, sellers, and possessors of ghost guns, while allowing licensed dealers a grace period for compliance.