A co-writer is typically a person that collaborates on the songwriting/creation process with you and receives an ownership stake in that song. A co-writer may, less likely, be the original writer of a song you sample. Co-writers are generally songwriters, composers, authors, lyricists and producers. Each writer should register every song that they have ownership stake in with their PRO, once the ownership splits have been agreed upon between all co-writers.
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