The Bakrie Group is selling a 23.8% stake in London-listed Bumi in a $1 billion (€730 million) deal aimed at avoiding a loan default.
Coal miner PT Borneo Lumbung Energi will buy the shares, after talks between the Indonesian family business and Swiss-based Glencore, the world's largest diversified commodity trader, failed.
The sale will go someway to paying back a $1.3 billion loan the family currently owes a syndicate led by Credit Suisse.