Eike Batista's OGX on Wednesday filed paperwork for the biggest bankruptcy proceeding ever in Brazil after the explorer said earlier this year that four of its five offshore fields were non-commercial.

The challenges and difficulties do affect the sector, impacting partners, suppliers and investors, Will Honeybourne, managing director at the First Reserve private equity firm, told attendees at OTC Brasil.

"It does cloud the water as to the attractiveness of independent E&P companies” in Brazil, Honeybourne said.

"We