Brazil’s leading mobile operator in terms of subscribers, Vivo, retained its top spot at the end of December 2005 with a 34.54% share of the 86.21 million-strong market, but its grip on the lead is weakening. According to figures published by Anatel, the cellco’s market share has slipped from 35.4% in November and 38.8% in April – when the regulator began compiling the data. Vivo is a joint venture between Telefónica Móviles of Spain and Portugal Telecom, and the only Brazilian operator backing CDMA technology. Its GSM-based rivals are catching up. Telecom Italia’s local unit TIM Brasil claimed 23.4% of the market, ahead of América Móvil-owned Claro with 21.6%. Meanwhile, Telemar’s Oi subsidiary claimed 11.9%, up from 11.6% the previous month.