In-vehicle device, information processing method and computer-readable medium

An in-vehicle device includes: a first communicator for inter-vehicle communication; a second communicator for communication with a predetermined transmission destination; and a storage configured to store first information pieces and a list including respective identification information pieces of the first information pieces; and a controller. The controller exchanges lists with a first in-vehicle device through the first communicator, and at a predetermined timing for transmitting the first information pieces stored in the storage to the predetermined transmission destination through the second communicator, when a predetermined condition is met, the controller does not transmit a first information piece included in the first information pieces and provided with an identification information piece included in both the list stored in the storage and a first list received from the first in-vehicle device and including respective identification information pieces of first information pieces each held by any of the other in-vehicle devices.