The logo of the Indonesia Stock Exchange (IDX) is seen at the IDX building in Jakarta on April 19, 2026. (JP/Iqro Rinaldi)

The Indonesia Stock Exchange (IDX) Composite index plunged as the market opened on Monday, extending its downward trend following the MSCI index rebalancing announced last week.The index opened down 1.4 percent at 6,447.97 when the market opened and the drop deepened to 4.4 percent ahead of the midday trading break.

A total of 736 stocks were down in the first trading session, 70 stocks advanced and 153 were unchanged. The biggest laggards include PT Dian Swastika Sentosa, one of the heavyweight stocks that were removed from the MSCI Global Standard Index.

MSCI announced its rebalancing review on the evening of May 12, with changes in constituents for its Global Standard Indexes set to take place after the stock market closes on May 29, and become effective on June 1.

In its latest review, MSCI added no Indonesian stocks but removed PT Barito Renewables Energy, PT Chandra Asri Pacific and PT Petrindo Jaya Kreasi, all affiliated with local conglomerate Barito Pacific, as well as PT Amman Mineral International and Dian Swastika Sentosa, the mining arm of Sinar Mas Group.