BAE Systems plc is a British multinational defence, security and aerospace company headquartered in London, United Kingdom, that has global interests, particularly in North America through its subsidiary BAE Systems Inc. BAE is among the world’s largest military contractors; in 2009 it was the second largest defence companies based on revenues. It was formed on 30 November 1999 by the £7.7 billion merger of two British companies, Marconi Electronic Systems (MES), the defence electronics and naval shipbuilding subsidiary of the General Electric Company plc (GEC), and aircraft, munitions and naval systems manufacturer British Aerospace (BAe).

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