The invention relates to a mobile data memory (1) comprising a data memory module (2) and a holding and/or carrying device (3), wherein the data memory module (2) has a non-volatile, re-writable semiconductor memory (4) and an access controller (5) with a communications module (7), wherein furthermore the communications module (7) is connected to a communications interface (8). The holding and/or carrying device (3) has a contact detection unit (16); the data memory module (2) furthermore has an allocation monitoring module (6) which is designed to evaluate the contact detection unit (16) and which is connected to the semiconductor memory (4) and/or to the access controller (5). The invention further relates to a method for person-based saving of information in a mobile data memory, wherein a remote communications station can access information saved in the data memory via a communications interface, and wherein a loss of the allocation of the mobile data memory to a person is detected. The data memory is deleted as soon as it is removed from the holding and/or carrying device.