Kosmos Energy acquired a 65 percent stake in Block 12, meaning that it now has stakes in four of Sao Tome’s 19 offshore blocks.
Block 12’s remaining stakes are controlled by Sao Tome and Principe’s National Petroleum Agency and Equator Exploration, according to a statement released by the agency.
Equator Exploration was not immediately available for comment.
“We are building our exploration portfolio during a time of opportunity in which there is less competition as a result of lower commodity prices,” said Thomas Golembeski, vice president for corporate communications.
The former Portuguese colony, which also has a joint exploration zone with Nigeria, is located in the resource-rich Gulf of Guinea but has yet to discover any commercially viable oil.