An increasing number of social movements have taken the form of connective action achieved through datafication structures in the absence of central coordinating social movement organizations. Social movement demobilization in digitally-mediated connective action remains a relatively understudied area. Drawing together social movement studies and communication studies, we introduce the theoretical framework of ‘implicated networks of demobilization’ (INsD) to explore the dynamics and implications of datafication for social movement demobilization. Based on examples from the Anti-Extradition Bill movement in Hong Kong and the 2020 George Floyd protests in the United States, we theorize that the connective action embedded in the datafication structure confronts three demobilizational dynamics: implicated data, materiality, and epistemic dynamics. These dynamics imply that connective action mobilization in datafied societies faces constraints pertaining to state-level network oppression, potential threats imposed by the material datafication structure, and the spread of digital knowledge of self-protection. The INsD framework contributes to understanding the interactive data-mediated dynamics between the state and activists in connective action.