The Mauser G11 was based on a 1974 patent by Industrie Werke Karlsruhe (IWK), an associate company of Mauser. The designers were Gerhard Hupp and Helmut Mader. In 1978, a physical prototype was constructed, but the project struggled to gain traction against the Heckler & Koch G11 and was cancelled shortly thereafter.
The Mauser G11 is a bullpup rifle, which was fed through an internal, 10-round helical-loading magazine. Ammunition is loaded into the weapon through a port on the side by the use of stripper clips. It has a cyclic rate that is speculated to be around 1500 rounds per minute with a muzzle velocity of 1000 meters per second, also speculated. The weapon also features a topside charging lever similar to those on early AR-pattern rifles.