The European Commission has published guidelines regarding the EU Regulation 2019/1150 “Platform to business”.
The regulation, directly applicable in the EU since July 12, 2020, set the contractual standards applicable to the relationship between online intermediation services (website allowing third parties to offer content, services or a sales area, such as marketplaces, Airbnb, etc.) and business users.
In particular, the regulation imposes minimum obligations concerning pre-contractual information, the terms of termination or suspension of intermediation services, and transparency regarding the criteria used for ranking offers and content.
The guidelines provide information on complying with the transparency obligations regarding ranking which include notably communicating on how remuneration may affect the presentation of content.
https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CELEX:32019R1150&from=FR