The Merger Reference (GEC, Siemens and Plessey) Order 1989
The General Electric Company, plc, Siemens AG, their subsidiaries and their associates are prohibited by this Order from acquiring any shares or interests in shares in The Plessey Company plc if together they would have 15 per cent or more of any class of voting shares, from exercising 15 per cent or more of voting rights and from making agreements with others to secure control of Plessey.