Cleary Gottlieb Steen & Hamilton is acting as issuer’s counsel to Brazilian oil and gas giant Petrobras on its plan to raise nearly $75 billion in the world’s largest-ever share sale to finance an investment program aimed at developing offshore oil fields.

Earlier this week, state-owned Petrobras agreed to issue $42.5 billion in new stock to the Brazilian government in order to obtain the rights to the estimated 5 billion barrels of oil in deepwater reserves like the Tupi field, one of the largest offshore oil discoveries of the last 30 years.