The Chinese firms, China National Offshore Oil Corporation ( CNOOC) and China National Petroleum Corporation (CNPC), have a 10 percent stake each, with Shell and Total taking 20 percent each, and Petrobras the remaining 40 percent share.

The Libra block is located in Santos Basin ultra deep waters in the pre-salt polygon and is considered a prospect of high potential. The total extension of the area is 1,547.76 km2 and was discovered by well 2-ANP-0002ARJS, drilled in 2010.


Under the rules of the auction, Petrobras had to participate in any consortium with at least a 30-percent stake, and to operate the field. The rules also called for the Brazilian government to receive a minimum 41.65 percent of the field's output, and that the auction should be decided based on the share of production offered by the consortium to the government.

The contract states that the block exploration phase will last four years. The minimum exploratory program, to be carried out during this period, includes 3D seismic for the whole block, 2 exploratory wells and 1 extended well test. 


There are minimum local [Brazilian] content requirements to be carried out in each phase of the project. For the exploration phase the minimum percentage of overall local content is 37%, in the development stage this percentage is 55% for systems with first oil until 2021 and 59% for those after 2022.


The Libra oilfield, the first to be auctioned under the new rules, which took years to approve, is estimated to hold eight to 12 billion barrels of recoverable oil, which would practically double Brazil's proven oil reserves.