Williams had previously entered into a license agreement with Winchester on September 9, 1940, for use of his patented short-stroke gas piston () in exchange for a royalty payable on the basis of the value of each gun manufactured containing the invention. From the end of 1941 and into 1942, Western Cartridge Co. (Winchester) negotiated with the Ordnance Department over the design of the M1 Carbine. In February 1942, the Ordnance Department proposed a one-time lump sum royalty payment of $886,000 in exchange for a royalty-free production license. On March 19, 1942, Williams voluntarily entered into another agreement with Winchester, accepting 26.411 percent of this lump sum ($234,100.46 over and above his salary) in lieu of royalty payments. Winchester signed the agreement on March 20, 1942.