Abstract: A data management system is constructed based on information related to multiple rights and comprises a data providing device that extracts and provides validity data corresponding to an external request from a database that manages validity data for each of the rights. The validity data includes a rating score indicating the relative validity among the plurality of rights. The data management system comprises a data analysis device for evaluating the validity of each of the plurality of rights. The data analysis device is capable of building the database described above that manages the rating scores for each of the plurality of rights. The data providing system comprises, for example, a data providing device and one or more information terminals.