An apparatus and method for transferring a Rights Object (RO) for a content between devices via a server, wherein a sending device converts a first RO taken by itself to encode into a second RO, and sends an RO move request message including the second RO to the server, whereas the server converts the second RO included in the RO move request message into a third RO and transfers the third RO to a receiving device, whereby the receiving device receives the third RO from the server for installation, wherein the sending device deletes or modifies the first RO at an appropriate time point.