A data process apparatus for sharing shared data among plural data process apparatuses participating in an event. The data process apparatus includes a participation notification reception unit configured to receive a participation notification from each of the plural data process apparatus including first and second data process apparatuses in the event, a notifying unit configured to notify the second data process apparatus to the first data process apparatus as a data obtain target from which the shared data is to be obtained. The second data process apparatus is a data process apparatus from which the participation notification has already been received by the participation notification reception unit.