OGPar said late on Wednesday that it had lost nearly 9.8 billion reais ($4.3 billion) in the fourth quarter and 17. 4 billion reais for the full year of 2013.
The loss came mainly as a result of impairment charges on exploration blocks where OGPar failed to find commercial hydrocarbons.
The company wrote down 8.9 billion reais on investments made in the Campos, Santos and Espirito Santo basins.
