Jakarta. The Indonesia Stock Exchange (IDX) announced on Friday that it is monitoring unusual market activity (UMA) in the shares of four listed companies after spotting irregular price movements.

The flagged stocks include Buana Artha Anugerah (STAR), which trades in commodity distribution such as yarn and fiber; Kokoh Exa Nusantara (KOCI), a player in real estate and construction; Graha Layar Prima (BLTZ), which operates in the entertainment sector; and Multisarana Intan Eduka (MSIE), a real estate services company focused on the education industry.

"The UMA announcement does not necessarily indicate a violation of capital market regulations," the IDX said in a statement. The bourse noted that it is reviewing trading patterns following the company's latest disclosure on September 16.

STAR has seen a sharp rally, climbing 41.1 percent over the past week to Rp 103 per share, surging 171.05 percent in a month, and up 106 percent year-to-date.

KOCI, meanwhile, slipped 10.1 percent to Rp 90 per share during Thursday's first session. Despite the dip, the stock has jumped 55.17 percent in a month and 80 percent year-to-date. Its latest disclosure came on September 12 in a shareholder registration report.

BLTZ has also drawn attention after soaring 45 percent in a month to Rp 2,610 per share, bringing its year-to-date gains to 30.5 percent. The company last issued a clarification on trading volatility on September 18.

MSIE advanced 4.65 percent to Rp 90 per share in Friday's first session, skyrocketing 190.32 percent over the past month and an eye-popping 592.31 percent so far this year. Its latest disclosure was a shareholder registration report on September 18.

The IDX urged investors to carefully review issuers' disclosures, assess their performance and transparency, and reconsider any corporate action plans that have yet to be approved by shareholders before making investment decisions.