Three regimes have turned the search box into a documented surface. The EU Digital Services Act requires large marketplaces to disclose the main parameters of their recommender systems, a transparency duty that scales by size and bites hardest on the very large platforms. The Platform-to-Business Regulation applies to online intermediation services and requires the main ranking parameters to be set out in the terms and conditions. Turkey's amended Electronic Commerce Law adds its own ranking and advertising transparency duties on intermediary service providers.
The enforcement is real. On 23 April 2025 the European Commission issued its first non-compliance decisions under the Digital Markets Act, fining Apple 500 million euros over anti-steering restrictions and Meta 200 million euros over its consent-or-pay model. Neither decision was about ranking, but the DMA separately prohibits self-preferencing in ranking as a breach in its own right.
So my questions to the product team are concrete. Which parameters move a listing up or down, and can we state them plainly? Where do our own products sit in that logic? Who can adjust the weighting, and is that change logged? The law asks for the main parameters; good governance keeps a decision log too. If a business user or a regulator asks why a competitor ranks above them, can we answer from records rather than from memory?
A ranking system that cannot explain itself is a liability waiting for a complaint. The time to write the explanation down is before someone demands it.
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