GECPlessey Telecommunications was founded in 1988 as a joint venture between GEC and the British electronics, defence and telecommunications company Plessey. A joint holding company of GEC and the German conglomerate Siemens AG acquired Plessey a year later, and GPT was converted into a 60/40 GEC/Siemens joint venture. During the mid-1990s, the name GPT gradually disappeared in the UK. By October 1997, the company evolved into Siemens GEC Communication Systems. In 1998, it was amalgamated into Siemens Communications. In August 1998, GEC acquired the 40% stake held by Siemens in GPT, and merged it into its newly founded subsidiary Marconi Communications. Through a series of mergers, divisions and restructuring in 1998/1999, GEC was renamed to Marconi plc, which was again restructured to Marconi Corporation plc in May 2003. In 2005, Marconi Corporation plc along with its subsidiary Marconi Communications, was sold to Ericsson and the remainder was renamed Telent plc.
History
Plessey takeover bid and formation of GPT: 1987–1989
The evolution of GPT can be traced to 1986, when the General Electric Company attempted a takeover of Plessey, a British-based international electronics, defence and telecommunications company founded in 1917. The takeover bid was barred by regulatory authorities. As an amicable solution, GEC and Plessey merged their telecommunications businesses on 1 April 1988 as GEC Plessey Telecommunications. GPT was a world leader in many fields, for example Synchronous Digital Hierarchy technology, and the merger brought the two companies responsible for developing and building the System X telephone exchange together, which was supposed to make selling System X simpler.
GPT – a GEC/Siemens joint venture: 1989 – 1998
In 1989, GEC and the German conglomerate Siemens made a hostile takeover of the Plessey Company through their joint holding company, GEC Siemens plc. While most of Plessey's assets were divided between the companies, GPT remained a joint venture with a 60/40 shareholding by GEC and Siemens respectively. In 1991, because Plessey no longer existed, GEC Plessey Telecommunications was renamed to just the initial letters GPT.
Split into Marconi Communications and Siemens Communications: 1998 – 2006
During the mid-1990s, the name GPT gradually disappeared in the UK, and by October 1997 the joint venture, through a series of Siemens mergers and acquisitions, evolved into Siemens GEC Communication Systems, which later in 1998 merged into Siemens Business Communication Systems to form the largest division of Siemens AG – Siemens Communications. In August 1998, GEC acquired Siemens' 40% stake in GPT and merged GPT with the telecoms units of its other subsidiaries, namely Marconi SpA, GEC Hong Kong and ATC South Africa to form Marconi Communications. In December 1999, GEC's defence arm Marconi Electronic Systems was amalgamated with British Aerospace to form BAE Systems. The remaining part of GEC was renamed to Marconi plc, and Marconi Communications became its principal subsidiary. Marconi decided to focus on the then-booming telecoms sector, but acquisitions made during the dot-com bubble took a heavy toll on the company following the "burst of the dot-com bubble" in 2000/2001. On 19 May 2003, Marconi plc underwent a major restructuring into Marconi Corporation plc. In 2005, the company failed to secure any part of BT's 21st Century Network programme, which sent the company's shares tumbling. The majority of Marconi Corporation's businesses were sold to Ericsson in 2005, and the remainder renamed Telent plc. On 27 October 2006, the company wound up voluntarily. The part of GPT which evolved into Siemens Communications would eventually merge into Siemens Enterprise Communications in 2008.
