A handheld device is configured to be connectable to a storage media that holds a unique media identifier and holds a content key data used to decrypt an encrypted content data. A content data delivery system is provided that is configured to be able to deliver various data to the handheld device and to make a content data available to the handheld device. The system includes a member-registration information database that holds member-registration information including a data pair of a handheld-device identifier related to the relevant handheld device and the relevant media identifier. The media identifier held by the storage media is verified with the member-registration information database.