The bill amends Title 11 of the General Laws by adding a new chapter, Chapter 47.2, titled "Unlawful Sale of Prohibited Firearms." This chapter defines various terms related to firearms, including "prohibited firearm," which includes specific types of semi-automatic shotguns, rifles, and pistols that meet certain criteria, such as magazine capacity and additional features like folding stocks, grenade launchers, and threaded barrels.

The bill establishes restrictions on the manufacture, sale, and purchase of prohibited firearms, making it illegal for individuals to engage in such activities unless exceptions apply. These exceptions include the transfer of firearms to federally licensed dealers or to individuals outside the state who may lawfully possess such weapons, as well as transactions involving law enforcement agencies.

Violations of these restrictions can result in severe penalties, including imprisonment for up to ten years, fines up to $10,000, and the forfeiture of the prohibited firearm. The bill also includes a severability clause, ensuring that if any provision of the chapter is held invalid, the remaining provisions will still be enforceable. The act is set to take effect on July 1, 2026.