Abstract: A content asset management system, a method and a control program capable of managing a content asset of each person while protecting benefit as property of these content assets are provided. Each person deposits a content subject that he or she owns in an object storage warehouse 109 of a service provider side. Content data indicating the content subject are stored in a content database on the basis of this, a relation of rights such as a list of content of the person is recorded in a user management database 107. A user who utilizes the content data, including the owner of the content subject, accesses the service side with a user terminal 101 to carry out authentication, causes a format converter 105 to convert the content data into a data format suitable for the person, and receives delivery from a content delivery server 102 to utilize them.