This vehicle-mounted device (100) is mounted in a vehicle (1) in which an autonomous driving system (300) is mounted, said vehicle-mounted device comprising: a request acquisition unit (111) which acquires a transfer request for transferring a control right, which is the right to control the autonomous driving system (300), from one of a plurality of occupants in the vehicle (1); and a control right management unit (112) which assesses whether or not a transfer requester, who is the occupant from whom the transfer request originated, is qualified to drive, and, on the basis of said assessment,determines whether or not to transfer the control right to the transfer requester.