An AR-15-style rifle is any lightweight semi-automatic rifle based on or similar to the Colt AR-15 design. The original ArmaLite AR-15, its predecessor, was a scaled-down derivative of Eugene Stoner's ArmaLite AR-10 design and featured selective fire. ArmaLite sold the patent and trademarks to Colt's Manufacturing Company in 1959, resulting in the Colt AR-15, which removed the selective fire feature. After most of the patents for the Colt AR-15 expired in 1977, many firearm manufacturers began to produce copies of the Colt AR-15 under various names. While the patents are expired, Colt retained the trademark of the AR-15 name and is the sole manufacturer able to label their firearms as AR-15.[1] AR-15-style rifles come in many sizes and have many options, depending on the manufacturer. The part shown bottom center is the lower receiver without the receiver extension, rear takedown pin, and buttstock. The Federal Assault Weapons Ban restricted the sale of the Colt AR-15 and some derivatives in the United States from 1994 to 2004, although it did not affect rifles with fewer listed features.[2][3] After the term modern sporting rifles was coined in 2009 by the US National Shooting Sports Foundation, a firearms trade association, it was quickly adopted by much of the industry.[4][5] In the 2010s, AR-15-style rifles became one of the "most beloved and most vilified rifles" in the United States, according to The New York Times; the rifles have gained infamy due in part to their use in high-profile mass shootings.[6] Promoted as "America's rifle" by the National Rifle Association, their popularity is partially attributable to active restrictions, or proposals to ban or restrict them.[7][8][9]
