Pinheiro Neto Advogados has helped Japanese corporation Mitsui buy into four oil exploration blocks off the coast of northern Brazil.

Mitsui bought a 10 per cent stake in the concession contracts of four oil blocks in the Barreirinhas basin from British oil company BG, which turned to Mattos Filho, Veiga Filho, Marrey Jr e Quiroga Advogados and Bracewell & Giuliani LLP.

The deal got the go ahead from Brazilian petroleum agency ANP on 19 November, after getting approval from antitrust authority CADE in July. Mitsui and BG agreed a price of US$70 million two years ago; however, it is not known whether the companies have since negotiated the price to take into account the fall in the price of oil since 2013, or the drop in value of Brazil's currency over the last 12 months. Since it began negotiations with Mitsui, BG has also merged with UK-Dutch oil explorer Royal Dutch Shell, in a US$70 billion deal announced in April, primed at taking advantage of BG's Brazilian oil assets.

Regulatory approval for the acquisition comes less than a month after Mitsui agreed to buy a minority stake in state-owned energy company Petrobras's gas distribution subsidiary Gaspetro, worth 1.9 billion reais (US$490 million), part of Petrobras's multibillion-dollar divestment programme.

The sale leaves BG with a 65 per cent stake in the contracts, while Thai state-run oil company PTT owns the remaining 25 per cent share. PTT bought its stake in the blocks in 2014, with the help of Trench, Rossi e Watanabe Advogados (associated with Baker & McKenzie), with BG Group's subsidiary, BG E&P Brasil, relying on familiar counsel Mattos Filho.

Counsel to Mitsui

Pinheiro Neto Advogados - Partners Ricardo Coelho and Marcello Lobo and associates Rafael Breves de Toledo and Caio Bernardes Vianna in Rio de Janeiro, partner José Alexandre Buaiz Neto in Brasília, and associate Marco Barbosa in São Paulo

Counsel to BG

Mattos Filho, Veiga Filho, Marrey Jr e Quiroga Advogados - Partner Giovani Loss and associates Felipe Feres, Andreia Saad, Frederico Donas, Fernando Ludke, Larissa Toledo, Luiz Izu and Stephanie Blattler in Rio de Janiero

Bracewell & Giuliani LLP - Partners Darren Spalding and Alastair Young in London