Rolls Royce Holdings Plc - ADR operates in the Aircraft engines and engine parts sector. Rolls-Royce Holdings plc, formerly Rolls-Royce Group plc is a provider of power systems and services for use on land, at sea and in the air. The Company operates in four segments: civil aerospace, defense aerospace, marine and energy. The civil aerospace is engaged in development, manufacture, marketing and sales of commercial aero engines and aftermarket services. The defense aerospace is engaged in development, manufacture, marketing and sales of military aero engines and aftermarket services. The marine segment is engaged in development, manufacture, marketing and sales of marine propulsion systems and aftermarket services. During the year ended December 31, 2010, it acquired ODIM ASA. In June 2011, Daimler AG and Rolls-Royce Holdings PLC had secured around 94% interest in Tognum AG-DJ. In September 2011, the Company acquired R Brooks Associates. In September 2011, the Company acquired R Brooks Associates.