A data processing apparatus includes an assignment database. The assignment database includes a user-information registration unit configured to collect pieces of user information about users authorized to operate a plurality of information processing apparatuses, and register each piece of user information and an identifier assigned to the corresponding user in association with each other; an output destination association table in which each piece of user information is associated with a printing apparatus that is to be an output destination; and an output-destination determining unit configured to determine the output destination of the output data by referring to the user-information registration unit and the output destination association table.