Rolls-Royce R engine was invaluable in the subsequent development of the Rolls-Royce Merlin engine and the Spitfire. A de-rated R engine, known as the Griffon, was tested in 1933, but it was not directly related to the production Rolls-Royce Griffon of 1939, of the same exact bore/stroke and resultant displacement figures as the "R" design. Three examples of the R engine are on public display in British museums as of 2014. Rolls-Royce realised that the Napier Lion engine used in the 1927 Supermarine S.5 Schneider Trophy winner had reached the peak of its development, and that for Britain's entrant in the next
Rolls-Royce Motor Cars most likely buyer was BMW, which already supplied engines and other components for Rolls-Royce and Bentley cars, but BMW's final offer of £340 million was beaten by Volkswagen's £430 million. A stipulation in the ownership documents of Rolls-Royce dictated that Rolls-Royce plc, the aero-engine maker, would retain certain essential trademarks, including the Rolls-Royce name and logo if the automotive division was sold. Although Vickers plc sold the vehicle designs, nameplates, administrative headquarters, production facilities, Spirit of Ecstasy and Rolls-Royce grille shape trademarks to Volkswagen AG, Rolls-Royce plc chose to license the Rolls-Royce name and logo to BMW AG for £40