O2 (UK) they can do it too" in reference to Vodafone and EE, O2's biggest competitors and the UK's top three mobile-telecoms companies. O2 (UK) Telefónica UK Limited (trading as O2 – stylised as O) is a telecommunications services provider in the United Kingdom, owned by the Spanish multinational Telefónica, and is headquartered in Slough. With 25 million subscribers (as of December 2017), O2 is the second-largest mobile network operator in the United Kingdom after EE, with Vodafone in third place. O2 was formed in 1985 as Cellnet, a 60:40 joint venture between BT Group and Securicor. In 1999, BT Group acquired
Intermountain West Communications Company to Sinclair that holds the licenses, with Sinclair operating the stations through joint operations and shared services agreements. The sale was approved on September 22, 2017, and completed on January 9, 2018. Notes: Note: Intermountain West Communications Company Intermountain West Communications Company is a defunct American telecommunications company, formerly owned by James E. Rogers (1938–2014), that remains as the licensee company for a number of local television stations in the United States, operated by Sinclair Broadcast Group and subsidiary companies Howard Stirk Holdings and Cunningham Broadcasting. Headquartered in Las Vegas, Nevada, IWCC was founded on October 1, 1979, following the