The Emergence of Misinformation in Platform Governance. A longitudinal study of social media platforms’ misinformation policies

Misinformation has become a key concern for the functioning of contemporary democracies, and social media platforms are considered a key site of misinformation. So how have platforms responded to this challenge? This study explores how the governance and conceptualization of misinformation by five major social media platforms (YouTube, Facebook, Instagram, X/Twitter, TikTok) has changed from their inception until 2023. Applying a longitudinal mixed-method approach, the paper traces the inclusion of different terms connected with the concept of ‘misinformation’ into the platforms' policies and examines periods of convergence and divergence in their handling of these. We identify three distinct phases: ranging from the formative period with a focus on delegated liability to a phase shaped by concerns about spam, scam to the politicization of misinformation since the late-2010s. These findings contribute to scholarly debates on platforms and policies by reconstructing the former. More broadly, this paper shows how the formation of platforms is responsive to societal concerns, political developments, changing business models, and specific external incidents (elections, conflicts, COVID-19).