Fragmentation in health systems leads to discontinuities in the provision of health services, reduces the effectiveness of interventions, and increases costs. In international comparisons, Germany is notably lagging in the context of healthcare (data) integration. Despite various political efforts spanning decades, intersectoral care and integrated health data remain controversial and are still in an embryonic phase in the country. Even more than 2 years after its launch, electronic health record (elektronische Patientenakte; ePA) users in Germany constitute only 1 per cent of the statutorily insured population, and ongoing political debates suggest that the path to broader coverage is fraught with complexities. By exploring the main stakeholders in the existing (fragmented) health system governance in Germany and their sectoral interests, this paper examines the implementation of ePA through the lens of corporatism, offering insights based on an institutional decision theory. The central point is that endeavours to better integrate health data for clinical care, scientific research and evidence-informed policymaking in Germany will need to address the roles of corporatism and self-governance.