This research develops and assesses a model based on capabilities that explains how platform-based open innovation networks enhance sustainability through sequential mediation processes. By relying on concepts of reflexive innovation, ecosystem learning, and knowledge co-creation, the research shows that participation in platforms enhances the maturity of the circular learning ecosystems; therefore, promoting collaborative reflexive practice. Reflexivity leads to two outcomes: (a) an individual-level increase in circular literacy, which implies an increase in knowledge, skills, and behavioral orientation to circularity, and (b) system-level sustainable platform-based innovation outcomes, comprising the social and environmental impacts of the innovational processes. The outcomes endorse the proposed mediation directions. Interestingly, the digital inclusivity orientation was not associated with the reflexivity-literacy relationship, signifying that inclusion requires a deeper organizational integration in order to generate high capability impacts. The study enhances the literature on circular economy and innovation by introducing the concepts of reflexivity and circular literacy as the strategic abilities of a company and providing managers and policymakers with insights on how to build inclusive and sustainability-oriented platform ecosystems.