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 Holdings Margaret Thatcher. In 2003 ownership of Rolls-Royce plc was passed to Rolls-Royce Group plc incorporated 21 March 2003 which issued its own new shares for payment to the previous shareholders. In 2011 in the same way Rolls-Royce Group plc passed ownership on 23 May 2011 to Rolls-Royce Holdings plc a wholly new company incorporated 10 February 2011. Rolls-Royce plc remains the principal trading company. Rolls-Royce Holdings plc, like its immediate predecessor, is merely a holding company. The 1980s saw the introduction of a policy to offer an engine fitment on a much wider range of civil aircraft types, with the