SPK Introduces Regulation to Address MSCI Criticisms

SPK's New Regulations In its bulletin dated September 8, 2026 (No.
2026/57), the Capital Markets Board (SPK) announced significant changes to share ownership reporting and effective circulation calculations for companies listed on Borsa Istanbul.
Share Ownership Notifications SPK lowered the reporting threshold for shares and voting rights from 5% to 3%.
The change will take effect on September 11, 2026.
Effective Circulation Calculation The new principle redefines the shares in effective circulation.
This concept, which indicates a company's public ownership ratio, will be calculated based on the observable shares of companies listed on the Borsa Istanbul Equity Market.
The ratio is determined by dividing the total number of shares outstanding by the number of observable shares.
Shares excluded from effective circulation include: Shares owned by public legal entities Shares held by founders and affiliated entities Repurchased shares Shares held by senior executives Shares held by foundations and endowments Indirect share ownership will also be considered; shares held by mutual and private funds, as well as shares in publicly listed companies, will be excluded from effective circulation to the extent that they correspond to the ownership percentage of the relevant fund or company.
Implementation and Purpose SPK's decisions will come into force from September 11, 2026.
The regulations aim to improve the accuracy of data used in index calculations by international index providers such as MSCI.
These changes will enable investors to assess the true liquidity of companies more accurately.