a copyright assignment is a document used when one person owns a copyright to any kind of work (such as a screenplay, novel, painting, or song) and wishes to transfer the ownership of that copyright to another person. often, copyright assignments are used when the rights to a work are being given away so that the party receiving the rights may use that work for any purpose they desire. they contain all the information needed to record the assignment with the united states copyright office, if so desired by either or both of the parties.