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
The O2 in October 2018, completes the loop of The O2, adding an extra floor in parts and providing space for 85 stores. Brands that have signed deals to take space include handbags maker Aspinal of London, Calvin Klein, Hackett, Ted Baker, Gant and Levi’s. In late 2007, Marine engineering consultancy, Beckett Rankine, were appointed to investigate the possibility of a cruise ship terminal being built. In 2012 it was reported that the O2 would be sold by its owners, Anschutz Entertainment Group (AEG), as part of the disposal of the entire company's assets, rumoured to be valued around $7 billion. The