My Data, Your Data, Our Data: Managing Privacy Preferences in Multi-Subjects Personal Data.

The evolution of mobile devices, the success of social networks, and the digitalization of business/personal services have resulted in a huge and con- tinuous production of Personal Data (PD). The creation of a balanced ecosys- tem of PD, where data act as the fuel for novel application scenarios, may drive the shift toward a user-centric paradigm, in which constraints should be im- posed on the data usage, to protect the individuals' privacy. The possibility for people to directly collect, manage and exploit PD introduces both technical and regulatory new issues in PD management. Uncertainty especially arises in the case of PD related to multiple subjects, e.g., containing identifiers referring to more than one person, each of which holds rights to control how these PD are treated. In this paper, we refer to this kind of valuable data as Multiple Subjects Personal Data (MSPD). The protection of MSPD in a user-centric paradigm is an undeniable requirement to ensure privacy to all MSPD right-holders. We discuss the relevance of MSPD, providing a technical approach to regulate their trusted management in a user-centric model context.