Röbert, KevinKevinRöbertKaaser, DominikDominikKaaserFischer, MathiasMathiasFischer2025-06-202025-06-202025-0340th Annual ACM Symposium on Applied Computing, SAC 2025: 506-508979-8-400-70629-5https://hdl.handle.net/11420/55916In an increasingly information-driven society, the volume of digital footprints left by individuals has surged significantly. Safeguarding the anonymity of data generated by computing devices is becoming more challenging as these offer deep insights into personal behaviors. We propose a user-centric and privacy-preserving data space for unlinkable data sharing based on a central intermediary. By integrating differential privacy techniques with fine-grained access control, our system allows data providers to store their data confidentially and unlinkable at the intermediary. Data consumers can then locate and request data via this intermediary, ensuring that data providers remain informed without revealing the origin of the data. Additionally, the intermediary facilitates continuous data sharing, requiring only a single data upload. Our approach is designed to protect data providers from both external and internal attackers, as well as from an honest-but-curious intermediary.enaccess control | data spaces | differential privacy | private data sharingTechnology::600: TechnologyConference Paper10.1145/3672608.3707708Conference Paper