A calculator system for performing duplication of contents does not necessarily perform screening, i.e., electronic watermark detection, rather, contents copy control information can be obtained otherwise. For example, in the event of copying a CD regarding which it is known beforehand that there is no electronic watermark inserted in the contents, the electronic watermark detection processing itself can be skipped as long as the CD can be confirmed to be such, thereby reducing the amount of time necessary for copying. Electronic watermark inspecting processing with heavy computation loads is performed vicariously for judging whether or not duplication of contents is permissible.