Marketplaces and sellers are subject to transparency duties on rankings, reviews and the identity of sellers.
Legal framework
- P2B Regulation (EU) 2019/1150: terms, ranking parameters, differentiated treatment
- DSA (EU) 2022/2065: dark patterns, ad transparency, recommender systems, traceability of traders
- UWG: § 5b(2) ranking parameters, § 5b(3) review authenticity, Annex Nos. 11a, 23b, 23c
Case law
- BGH, 25 July 2024, I ZR 143/23 – average star ratings require total number and period
- BGH, 20 Feb 2020, I ZR 193/18 – sellers are not liable for customer reviews they neither initiated nor adopted
Case examples
Paid ranking
A marketplace places sponsored offers at the top of search results without labelling. Blacklisted.
Review import
A seller copies reviews of a similar product from another platform. Misleading and potentially fake reviews.
