Brazilian telecom Oi is the country's first quad play operator, and is headquartered in Rio de Janeiro. Its services include fixed-line and mobile telecommunication services, broadband, subscription television, internet service providers (ISPs) and other services, for residential clients, small, medium and large companies, and governmental agencies. In 2009, the company acquired a controlling stake in Brasil Telecom Participações, which was merged with Tele Norte Leste Participações three years later, changing its name to Oi S.A. The firm operates in three Brazilian regions - Region I, consisting of 16 states in the northeast and southeast of Brazil; Region II, consisting of the Federal District and nine states in the west, midwest and south of Brazil; and Region III, which covers the state of São Paulo. In 2012, Oi acquired 4G LTE frequencies in order to launch 4G technology nationwide and currently provides 4G in over 133 cities. In 2013, it announced the merger of operations with Portuguese telco Portugal Telecom (PT).