We explore a potential paradigm shift in personal health data management, where individuals gain ownership and sovereign control over their records. We assess the potential of decentralized content-addressable storage (DCAS) networks as a foundation for person-owned personal health records (PHRs). After defining the principles of DCAS-based health data storage, we contrast it with conventional systems such as hospital EHRs, national health information systems (e.g., Estonia’s national health information systems, EHIS), and commercial apps collecting data from wearables. We analyze key organizational and technical aspects of DCAS-stored health data—custody, security, quality, transparency, anonymization, and interoperability—in the context of ongoing research at eMedLab, TalTech. Finally, we propose initial organizational, economic, and technical integration scenarios linking DCAS-based PHRs with existing national and commercial health IT systems. These are discussed within the European Health Data Space (EHDS) framework, considering both primary (care delivery) and secondary (research, public health, AI) uses. We contribute to the debate on secure, interoperable, and ethically sound health data governance by outlining this shift toward full individual data ownership.