Virtually all areas of everyday life are influenced by the digital revolution and one of the most affected is the public sphere. With the emergence of the internet, and especially with the platformization of internet services of the last decade, the public sphere, previously organized around radio broadcast, television and printed press, is now facing the competition of social networks. Social media platforms have revolutionised our ability to connect across historic social, political and geographic divides. However, this also means that increasingly these platforms are operating as “gatekeepers”, deciding which kind of speech is allowed or censored. An immense regulatory challenge arises because social networks have a specific legal status: private but opened to the public. Social media platforms have been exempt, so far, from traditional duties of due process and respect of human rights, representing an unprecedented challenge to the protection of freedom of expression.