Does Renewal Apply to Both Published and Unpublished Works?

Dear Rich: A song was first copyrighted in an “unpublished” form in 1950, and subsequently, in the same year, the same song was copyrighted in “published” form. The published registration was renewed in a timely fashion. The unpublished copyright was not renewed. Does the renewal of the published work protect the rights of the composer? Or does failing to renew the unpublished version put the song in the public domain?

If the copyright was renewed, it’s protected for 95 years from the first publication. If the music was published in 1950, it wouldn't become public domain until 2045. It doesn't matter that the unpublished version was never renewed unless the unpublished version contains material that differs from the published version. For example, if the unpublished version contains an intro that's not present in the published version, the intro would be public domain.