EMR, Farallon Capital and other partners hold 95% of the mine.
The stake will be purchased by PT Danusa Tambang Nusantara, a company controlled by by PT United Tractors Tbk and PT Pamapersada Nusantara.
Martabe is one of Asia's largest gold mines with reserves of 4.7 million ounces of gold and 36Moz of silver, and resources of 8.8Moz of gold and 72Moz of silver.
The mine produced 355,000oz of gold and 2.8Moz of silver last year at all-in sustaining costs of $406 an ounce of gold.
EMR CEO Jason Chang said significant growth had been achieved at Martabe under the company's ownership.
"Throughput and gold and silver produced have substantially increased, reserves have doubled, and AISC is now amongst the lowest in the world," he said.