The ultimate holding company is Rolls-Royce Group plc. Rolls-Royce Group plc shares are listed on the London Stock Exchange. As a holding company, Rolls-Royce Group plc does not trade on its own account. Registered office......The ultimate holding company is Rolls-Royce Group plc. Rolls-Royce Group plc shares are listed on the London Stock Exchange. As a holding company, Rolls-Royce Group plc does not trade on its own account. Registered office: 65 Buckingham Gate, London SW1E 6AT Company number: 4706930 Registered in England. The groups main operating subsidiary is Rolls-Royce plc. All of the business activities of the group are carried out by Rolls-Royce plc and its subsidiaries. Registered office: 65 Buckingham Gate, London SW1E 6AT Company number: 1003142 Registered in England. Indirectly held companies, incorporated within the UK Civil aerospace Optimized Systems and Solutions Limited (OSyS) - Advanced controls and predictive data management Rolls-Royce Aircraft Management Limited - Sales finance and other financial services Rolls-Royce Leasing Limited - Engine leasing Rolls-Royce Total Care Services Limited - Aftermarket support services Marine Rolls-Royce Marine Electrical Systems Limited - Marine electrical systems Rolls-Royce Marine Power Operations Limited - Nuclear submarine propulsion systems Energy Rolls-Royce Fuel Cell Systems Limited - Development of fuel cell systems Rolls-Royce Power Development Limited - Provision of project development capabilities Corporate Rolls-Royce International Limited - International support and commercial information services Rolls-Royce Power Engineering plc - Power generation and marine systems The above companies operate principally in the UK and the effective Group interest is 100 per cent, other than Rolls-Royce Fuel Cell Systems Limited in which it is 80 per cent.