O2 (UK) BT subsidiaries: Esat Digifone in Ireland, Viag Interkom in Germany and Telfort Mobiel in the Netherlands. The rebranding was supported by a European advertising campaign, which began on 16 April 2002, across all four countries, at a cost of £130 million. The main launch campaign ran from 18 June and was developed by Vallance Carruthers Coleman Priest, working alongside brand consultancy Lambie-Nairn, creators of the "O2" brand identity. In March 2005, mmO2 restructured its shares and the company was relisted as O2 plc. On 30 November 2005, O2 agreed to a takeover by Telefónica, a Spanish telecommunications company, for £17.7
O2 Czech Republic O2 Czech Republic O2 Czech Republic (operating under the O brand) is a major integrated operator in the Czech Republic. It is now operating more than six million lines, both fixed and mobile, making it one of the Czech Republic’s leading providers of fully converged services. O2 Czech Republic operates a fixed and mobile network including a 3rd generation network, CDMA (for data), UMTS and EDGE, enabling voice, data and video transmission. O2 Czech Republic is also a provider of ICT services Previously two companies, fixed-line operator Český Telecom and mobile operator Eurotel, it was acquired by the Spanish company