Mammoth internet platforms, like Facebook and Google, regulate the behavior of billions of individuals. These companies set and enforce norms through user agreements, design, and algorithmic regulation. But users do not actively and consciously participate in these regulatory processes, which penetrate deeply into users’ lives. Public law is well equipped to deal with state sovereign power. Yet this body of laws finds itself helpless when facing platforms’ emerging political authority. This article analyzes the quasi-sovereign power of platforms, the threats it creates to users' political freedom and to the public sphere, and the theoretical trap that makes it difficult to address these risks. To resolve this bind, the article proposes the creation of legal structures that will allow users to self-manage via representative unions. The integration of users’ collective voice within the corporate governance of platforms could help to respect, protect and fulfill users’ political rights.