Regulation Watch · Business Licensing · Indonesia. The announcement changes the constituent-selection and review methodology for the Indonesia Stock Exchange Composite Index, or IHSG. It affects securities listed on IDX and investors, funds and financial products that use the IHSG as a benchmark or reference. It does not delist an affected security or amend the issuer's company or operating licences.
IDX Excludes High-Concentration Shares from the IHSG
IDX Announcement Peng-00201/BEI.POP/10-2026 removes High Shareholding Concentration shares from the IHSG from 2 November 2026, changes the quarterly review calendar and adds immediate off-cycle adjustments.
- Published
- IDX issued Announcement Peng-00201/BEI.POP/10-2026 on 21 October 2026. The official IDX press release was published on 23 October 2026. The announcement is an exchange methodology instrument and does not identify a State Gazette promulgation date.
- Effective
- 2 November 2026.
- Added to Watch
- 23 October 2026
Who is affected
Indonesian and foreign investors, investment managers, index funds and exchange traded funds, pension and insurance portfolios, securities companies, custodians, benchmark and data providers, listed PT PMA and PT PMDN companies, controlling and other shareholders, directors, commissioners, corporate secretaries, investor-relations teams and advisers monitoring free float and ownership concentration.
Practical impact
Shares classified by IDX and KSEI as having High Shareholding Concentration, or HSC, will no longer be included in the IHSG while that classification applies. The prior selection rule excluded only shares on the Acceleration Board. The capped free-float-adjusted market-capitalisation method and 9 percent cap remain unchanged. Regular reviews move from March, June, September and December to January, April, July and October, with results effective on the first exchange day of February, May, August and November. A share that enters or exits HSC status between regular reviews will now be adjusted in the IHSG immediately rather than waiting for the next quarterly review.
IDX issued Announcement Peng-00201/BEI.POP/10-2026 on 21 October and set 2 November 2026 as the effective date. The change updates the methodology for selecting and reviewing securities in the IHSG, Indonesia's broad exchange composite index.
The central change is the treatment of High Shareholding Concentration. The former selection rule included all listed shares except those on the Acceleration Board. From 2 November, shares published by IDX as HSC are also excluded from the IHSG while that classification remains in force. The calculation method remains capped free-float-adjusted market capitalisation with a maximum 9 percent weight.
HSC status comes from the IDX and KSEI framework established by Joint Decision Kep-00047/BEI/03-2026 and KEP-0024/DIR/KSEI/0426. Under that framework, IDX and KSEI review concentrated ownership and IDX publishes the resulting HSC status. When a later review or written issuer confirmation shows that the concentration condition has ended, the exchange publishes a further notice.
The review calendar also changes. Regular IHSG evaluations move to January, April, July and October, and the results become effective on the first exchange day of February, May, August and November. The announcement additionally introduces an off-cycle mechanism: when a share enters or exits HSC status outside the regular timetable, the IHSG will be adjusted immediately.
The measure changes benchmark composition, not listing status. An HSC share remains listed and tradable unless a separate exchange action says otherwise. Investors should distinguish an IHSG exclusion from a suspension, board transfer or delisting, and should apply the investment mandate and risk controls governing their own portfolio.
Index-tracking and benchmark-aware portfolios should identify affected holdings, model the revised weights, confirm authorised execution steps and update review calendars before 2 November. Listed companies and shareholders should monitor official HSC publications and reconcile ownership records because later HSC changes can now affect the IHSG without waiting for the next quarterly review.
Required action
- Identify portfolios, mandates, performance reports, valuation models, covenants and investment products that track, reference or compare performance with the IHSG.
- Obtain the current official HSC status for each relevant listed holding and do not treat exclusion from the IHSG as a delisting, trading suspension or automatic investment prohibition.
- For passive or benchmark-aware portfolios, model constituent and weight changes before 2 November 2026 and approve any rebalance, liquidity and execution plan under the fund mandate and applicable OJK rules.
- Update systems and calendars for regular IHSG reviews in January, April, July and October and first-exchange-day implementation in February, May, August and November.
- Create an event-driven control for IDX announcements that add or remove a security from HSC status because off-cycle IHSG treatment can now apply immediately.
- Listed companies and significant shareholders should reconcile KSEI ownership records, public-float disclosures and investor-relations materials, and promptly investigate any unexpected HSC publication.
- Preserve the 21 October announcement, the applicable HSC notice and the calculation or investment decision record for audit, investor reporting and mandate-compliance purposes.