It is important to make the distinction between the groups Rolls Royce plc and Rolls Royce Ltd. In fact, Rolls Royce Ltd is an old subsidiary of the Rolls Royce Group that was acquired by the German automobile manufacturer Volkswagen. The company Rolls Royce Plc that we examine in this article is the group that is specialised in the production and development of engines, not for automobiles but for the aeronautical sector. As both companies are quoted on the stock markets it is important not to confuse them.