Facts
The Turkish Competition Board opened an investigation into Trendyol (DSM Grup Danışmanlık İletişim ve Satış Ticaret AŞ), one of Türkiye's largest e-commerce platforms, by a decision of 23 September 2021. Trendyol runs a marketplace for third-party sellers and, on the same platform, sells its own private-label products. The investigation examined whether the platform's product ranking and scoring algorithms had been tuned in favour of its own retail business, and whether data generated by sellers on the marketplace had been used for the private-label range. The Board decided the case at its meeting of 26 July 2023 and published the operative part under Article 49 of Law No. 4054.
Question
Does a platform that is dominant in the multi-category e-marketplace market abuse that position, within Article 6 of Law No. 4054 on the Protection of Competition, when it intervenes in its ranking algorithm and uses third-party sellers' data to promote its own retail business? The Board also had to consider whether it could impose behavioural remedies governing how the algorithms are applied, which internal teams may access which data, and how changes to the algorithms must be recorded.
Decision
The Board unanimously found that Trendyol was dominant in the multi-category e-marketplace market, that it had given its own retail business an unfair advantage by intervening in the algorithm and using third-party sellers' data, and that this infringed Article 6. It imposed an administrative fine of TRY 61,342,847.73. It also ordered Trendyol to apply its ranking and scoring algorithms equally to all sellers regardless of identity, to refrain from manual interventions favouring private-label products, to stop using marketplace data for those products, to keep versioned, tamper-evident records of algorithm code and parameter changes for three years, and to report annually for five years. Non-compliance carries daily fines.
Why it matters
The decision shows that in self-preferencing cases involving platform algorithms the Board may go beyond a fine and impose technical obligations on how the algorithm operates and how it can be audited. The duty to keep versioned records of code and parameter changes is designed to make ranking systems reviewable after the fact. The decision can be challenged before the Ankara administrative courts; the outcome of any such challenge could not be verified for this entry.
Related stages
A separate investigation into Trendyol's automated pricing tool ended on 3 October 2024 with commitments made binding by decision 24-40/950-409 (see the automated pricing entry).