Netherlands-based Mazarine Energy has agreed to acquire Black Sea Oil & Gas (BSOG) from Carlyle and the European Bank for Reconstruction and Development, Offshore Energy reported. The transaction would bring Romania’s largest offshore gas producer into Mazarine’s business, extending the buyer’s existing presence in the country’s energy sector. Completion remains subject to the usual regulatory approvals.
BSOG led investment exceeding $400 million in the Midia Gas Development (MGD) project, according to the report. Offshore Energy described the development as the first offshore hydrocarbon production hub established in the Romanian Black Sea for more than three decades. The project began producing in June 2022 and has since become a significant source of domestic gas supply for Romania.
MGD’s infrastructure comprises the Ana offshore platform, a subsea pipeline stretching 126 kilometres and an onshore gas treatment plant at Vadu, in Romania’s Constanța County. Offshore Energy reported production of more than 100 million standard cubic feet of gas a day. Citing monthly reports from ANRE, the outlet said MGD accounted for 11.8% of Romania’s total natural gas production during the first six months of 2026.
Mazarine said BSOG would retain its role as operator of MGD following the acquisition, preserving operational continuity as the business moves into its next stage of development. The purchase builds on the Dutch company’s established Romanian operations rather than marking its entry into the market. Mazarine is a privately owned oil and gas exploration and production company focused on subsurface expertise.
In comments carried by Offshore Energy, Mazarine said Romania had been central to its business since 2017. It characterised MGD as an important contribution to the country’s energy security and expressed its intention to build on the BSOG team’s work while supporting Romanian energy supplies over the coming years.