Some international investors in PT Adaro Energy (ADRO.JK) have approached other companies to sell around a combined 17% stake in the coal miner via a private sale, several people familiar with the situation said Thursday.

Goldman Sachs, which has a 9.94% stake in Indonesia's second largest coal miner by output, is coordinating the sale, the people told Dow Jones Newswires. However, it is unclear who the sellers are.

International investors, which include Citigroup (C), hedge fund Farallon's unit Noonday Asset Management, the Government of Singapore Investment Corp, or GIC, Kerry Coal and Goldman together hold at least a combined 25% stake in Adaro.

A person familiar with the situation said GIC and Kerry Coal are unlikely to be among the sellers.

Adaro officials declined to comment when contacted by Dow Jones Newswires.

The company said in October that some international institutional investors holding a significant block of Adaro shares had approached the company's founding and controlling shareholders and offered to sell back their shares for $250 million. But they failed to reach an agreement on the price.

The company's top five shareholders are PT Saratoga Investama Sedaya with a 14.93% stake, PT Triputra Investindo Karya with 13.34%, PT Persada Kapital Investama with 11.01%, Chief Executive Garibaldi Thohir with 7.8% and PT Trinugraha Thohir with 7.8%.

Adaro's shares fell 2.1% Thursday to IDR950, while the overall market rose 1.97% on talk that several investors were offering the sell their stakes in the company, dealers said.

-By I Made Sentana; Dow Jones Newswires; 62-21 39831277; I-Made.Sentana@dowjones.com

(Nisha Gopalan in Hong Kong and Costas Paris in Singapore contributed to this article.)