Petrobras Secures 75% Operating Stake in São Tomé Block 3 from Arthur Eze’s Oranto

Petrobras expands its West African footprint by acquiring a majority operating stake in Block 3 from Arthur Eze’s Oranto Petroleum.

By: AXL Media

Published: Apr 19, 2026, 11:25 AM EDT

Source: Information for this report was sourced from Business Insider Africa

Strategic Expansion into West African Frontiers

Petrobras has significantly deepened its operational presence in West Africa following the acquisition of a 75% operating interest in Block 3, located offshore São Tomé and Príncipe. The agreement, finalized on April 17, involves the transfer of operatorship from Oranto Petroleum, a firm founded by Nigerian multi-millionaire Arthur Eze. This move represents a major shift in the block's ownership structure, which was previously dominated by Oranto’s 90% holding, and marks a significant step in Petrobras’ renewed international push to secure high-potential exploration assets.

Alignment with 2026-2030 Portfolio Strategy

The acquisition is a direct result of Petrobras’ strategic plan for the 2026–2030 period, which prioritizes the diversification of assets and the replenishment of oil reserves through frontier exploration. Having earmarked approximately $1.3 billion for international exploration over the next five years, the Brazilian state-owned giant is targeting discoveries that can offset the natural decline of its aging domestic fields after 2030. By securing a majority stake in Block 3, Petrobras is positioning itself to leverage its deepwater expertise in a region that currently mirrors the company's long-term growth objectives.

Geological Synergy with Brazil’s Pre-Salt Basins

Petrobras’ interest in the Gulf of Guinea and southern Africa is largely driven by the geological similarities between West African offshore regions and Brazil’s prolific pre-salt basins. These conjugate margins were formed during the same tectonic events, leading to comparable hydrocarbon-bearing structures. Since its return to the African continent in 2024, Petrobras has aggressively built a portfolio across São Tomé and Príncipe, Namibia, and South Africa, viewing the region as a natural extension of the deepwater success that fueled Brazil’s domestic oil boom.