Any recorded song is legally divided into two distinct entities : the Song itself ( the words and music, written and composed by an artist ), and the Recording ( the actual recorded interpretation of a given song ).
This means two separate companies are involved in clearing rights for a song, and each is entitled to receive royalties on the part they own.
Music Publishers own the Song’s copyrights ( words and music ), while Record Labels own rights to a recording ( be it a studio recording or a live recording ).