Borsa Istanbul announced on Tuesday that it will remove more than a quarter of the securities currently comprising its flagship BIST-100 index, with the changes taking effect from the coming month. The exchange did not provide a specific reason for the overhaul.
The move follows a week in which the Central Bank of the Republic of Turkey injected additional liquidity into the capital market after several asset managers faced cash shortages that sparked a broad sell‑off in equities. Over 100 affected funds were subsequently forced into liquidation, and authorities detained a number of individuals on suspicion of market manipulation.
Among the stocks slated to exit the index are the financial institutions Destek and Katilimevim. Both companies saw their share prices multiply earlier in the year, but most of those gains have been erased in recent weeks. Several of the liquidated funds had been among the largest shareholders of the two firms.
Borsa Istanbul also said it will revise the criteria for inclusion in its leading indices. Membership in the "Star Market" segment will remain a prerequisite, requiring companies to meet defined equity thresholds. In addition, the exchange will now factor in the volatility of a stock’s price when assessing eligibility. Onurcan Bal, an investment adviser at Gedik Yatirim, welcomed the reforms, saying they should lead to more balanced price formation and make the Star Market a more reliable benchmark for investors.
The index reshuffle is expected to affect index‑linked products and passive funds that track the BIST-100, prompting portfolio adjustments as the new composition is reflected in market data providers.
