Disclosed is a method for causing either encrypted first content data or
unencrypted second content data, to be selectively recorded to a storage
medium in a data recording apparatus. When the data recording apparatus
is to return the encrypted first content data to the data transfer
apparatus, the return is inhibited if the data are judged to have been
edited. Upon return of the encrypted first content data, a content ID
held by the data recording apparatus regarding the first content data is
matched against a content ID held by the data transfer apparatus
regarding the received data. Where the encrypted first content data are
known to have been edited, the content ID matching process is omitted.