An image-forming system includes a data-reading unit, a data-writing unit, and a restricting unit. The data-reading unit reads additional data from a first storing member of an original document. The data-writing unit writes the read additional data to a second storing member of a recording medium. The restricting unit gives a restriction to the additional data stored in the first storing member after the additional data is read, in order to prevent the additional data stored in the first storing member from being read subsequently.