Chevron won the bidding rights to drill for oil in the Frade field in the Campos Basin and contracted Transocean for drilling purposes.

FORBES: Transocean Faces Possible Lawsuit After Brazil Oil Spill

Chevron was partnering with Brazilian oil company Petrobras to drill for hydrocarbons at the Frade Field in the Santos Basin in the Atlantic when the Nov. spill occurred.

FORBES: Chevron Not Leaving Brazil

Chevron had been banned from producing in the Frade field, and in Brazil in general, after more than 100, 000 gallons of crude flowed into the Atlantic Ocean two Novemebers ago.

FORBES: Chevron's Production And Refining Down While Brazil Authorizes Ultra-Deepwater Drilling Again

Chevron miscalculated its drilling of its Frade field last November, an oil well just under the ocean floor in the Santos Basin in Brazil, about 70 kilometers off coastal Rio de Janeiro.

FORBES: For Brazil Oil Spill, Chevron Gets A Discount

More recently, Brazilian courts dropped criminal charges against the firm relating to its involvement in an oil spill in the Frade oil field, off the coast of Brazil.

FORBES: Quick Take

Everyone has seen how the Brazilian government reacts to environmental lapses, slapping heavy fines on Chevron for seeping 3, 700 barrels of crude into the Atlantic Ocean from the Frade offshore field.

FORBES: Has Unconventional Oil Production Peaked?