Marathon Oil Corp. on Friday said a unit of Angola's state-owned oil company Sonangol agreed to buy a 20 percent interest in an area offshore Angola for $1.3 billion.
Sonangol, which is already a partner in the Angola Block 32, exercised its right of first refusal, effectively trumping the deal Marathon had struck in July to sell the stake to CNOOC International Ltd. and Sinopec International Petroleum Exploration and Production Corp.
The move doubles Sonangol's stake in the high quality oil-bearing reservoirs to 40 percent from 20 percent. Other partners include Total Exploration and Production Angola, Esso Exploration and Production Angola and Petrogal.
Marathon said it will retain a 10 percent working interest in the property. When the sale was announced in July, Marathon said the divestiture would help balance its overall portfolio by redirecting proceeds to other growth regions.
The parties expect to close the transaction in January.
Shares of Marathon fell 21 cents to $31.34 in morning trading.