The 10 companies that have data room access include US independent Anadarko, Australia's BHP Billiton, UK supermajor BP, US supermajors Chevron and ExxonMobil, Japan's Inpex and Mitsubishi, European supermajors Shell and Total, and Malaysia's Petronas, according to government data.

Juan Carlos Zepeda Molina, president of the country's National Hydrocarbons Commission, was pleased with the level of interest.

"It's a good number," he said on the sidelines of an AAPG/SEG industry event in Cancun.​

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