The Regulation Amending the Regulation (“Regulation”) on the Principles of Stock Exchange Activities of Borsa İstanbul A.Ş. (“Amendments”) prepared by the Capital Markets Board (“CMB”) was published in the Official Gazette dated 23 July 2025 and entered into force.

Amendments have been introduced in accordance with the existing Borsa İstanbul A.Ş. (“Borsa”) rules regarding the establishment and governance of financial benchmarks that are compliant with the principles of the International Organization of Securities Commissions (IOSCO), including the BIST Equity Indices, BIST KYD Indices, BIST Sustainability-Themed Debt Securities Indices, BIST Commodity and Commodity-Based Asset Indices, and the Turkish Lira Reference Interest Rate (“TLREF”) and BIST TLREF Index, which are regularly calculated and published by Borsa and have been updated as of 31 December 2024. Key highlights regarding the Amendments and the ongoing Borsa practices are presented below:

a. Establishment of Financial Benchmarks

Borsa is responsible for the calculation and publication of financial benchmarks in an accurate and timely manner, through reliable and transparent governance processes, as well as for their oversight and supervision. Borsa is also responsible for the establishment of appropriate reporting and complaint mechanisms regarding the compliance of the financial benchmarks. All related processes are carried out in accordance with the directives and procedures of Borsa.

When designing financial benchmarks, Borsa aims to ensure that they accurately and reliably reflect the economic realities of the changes intended to be measured, while maintaining sufficient transparency. In relevant calculations, Borsa considers the use of appropriate and adequately sized samples, the volume and liquidity of the markets, the distribution of transactions among market participants, and market dynamics.

For the purpose of calculating financial benchmarks, Borsa may outsource data, including prices, yields or rates of financial instruments, provided that it monitors and oversees the relevant procurement and data acquisition processes.

b. Prevention of Conflicts of Interest

Borsa implements necessary measures to identify, disclose, manage, prevent, and mitigate conflicts of interest, appropriate to the level of risk associated with the financial benchmark. These measures primarily aim to ensure that personal interests and relations do not adversely affect Borsa’s activities, to control the confidentiality and exchange of information and data, to ensure that financial benchmarks are reviewed by competent staff with segregated responsibilities, and to prevent conflicts of interest between financial benchmark activities and Borsa’s other operations.

c. Control, Oversight and Audit

In order to ensure the reliability, integrity and accountability of the financial benchmark calculation processes, Borsa establishes appropriate control and oversight mechanisms. Within this framework, the control system covers measures for preventing conflicts of interest, ensuring the reliability of inputs, maintaining the effectiveness of accountability mechanisms, risk management infrastructure, effective reporting mechanisms, and ensuring employee competence. The oversight mechanism, on the other hand, involves the evaluation of the scope of benchmark usage, the materiality of potential conflicts of interest, relevant rules, procurements and audit processes.

In addition, Borsa appoints an independent internal or external auditor with sufficient expertise and knowledge to review and report on the financial benchmark calculation processes at intervals not exceeding two years.

***

The principles set forth in Borsa’s Directive on Financial Benchmarks Compliant with the IOSCO Principles, regarding the establishment, management and oversight of financial benchmarks have also been framed by CMB at the regulation level, thereby reinforcing the binding nature of compliance with these rules. Within this scope, Borsa’s existing and future directives and procedures will remain applicable at the secondary level, provided that they comply with these principles. Furthermore, the supervision of Borsa’s establishment of financial benchmarks and related activities by CMB will also be carried out on the basis of these binding rules, which are now directly adopted under the Regulation.