* Registered Brazil companies include Petrobras, Batista's OGX
* Exxon Mobil, Chevron from the United States also qualified
* China's CNOOC and Sinochem, France's Total also on list
RIO DE JANEIRO, April 4 (Reuters) - Brazil's oil regulator said on Thursday that 71 companies have signed up to bid in the country's 11th round auction of oil exploration and production rights in May, the first such sale in Brazil in five years.
The companies come from 18 countries and three British overseas territories, said the regulator, known as ANP. The largest number of companies registered for the May 14-15 auction are from Brazil, with 19, followed by the United States with eight.
The Brazilians include state-controlled oil company Petroleo Brasileiro SA, known as Petrobras, and OGX Petroleo e Gas SA, the Brazilian oil company controlled by Brazilian billionaire Eike Batista's troubled Grupo EBX.
Lower than expected oil output at OGX has caused the company's stock to plunge and raised expectation Batista will seek new areas in an effort to increase the company's long-term prospects.
U.S. companies signed up to bid include Exxon Mobil Corp and Chevron Corp.
Six companies from Great Britain and five each from Canada and Japan have also signed up along with three each from Australia, the Cayman Islands and Colombia. Two companies each from China, Spain, France and Norway will also bid.
The Chinese companies are CNOOC and Sinochem . Others are Spain's Repsol SA, France's Total and Great Britain's Royal Dutch Shell Plc .