The Vivo brand was launched on 13 April 2003, as a mobile phone service provider. It's the largest provider in Brazil with over 76 million users.[3] It originated from the merger of several Brazilian mobile phone operations under a joint-venture owned equally by Portugal Telecom (PT) and Spain's Telefnica. Until 2006, the group was composed of six holding companies which, as announced in November 2005, merged into a single holding company, "Vivo Participaes". The operation was concluded on 22 February 2006. In July 2010, Telefnica bought PT's shares.[4][5]