Exxon Mobil Corp. signed an agreement with Pemex as Mexico’s oil industry opens to private investment.

The two companies signed a three-year memorandum of understanding and cooperation to exchange academic, scientific and technical knowledge, according to e-mailed statements by both companies. The companies agreed to analyze exploration, drilling and refining opportunities, according to Pemex’s statement.

The Irving, Texas-based company joins a growing list of major oil producers to express interest in entering Mexico’s energy industry, which is ending a 76-year state oil monopoly. Congress passed legislation last year to allow private companies to tap the country’s 13.4 Bbbl of proven reserves, which the government estimates will bring in $50 billion of investment between 2015 and 2018.

Chevron Corp., Noble Energy Inc. and BHP Billiton Ltd. are among companies interested in exploring for oil in Mexico. Authorities next year will auction 169 oil blocks—109 for exploration and 60 for production.