As I understand the legalities (lawyers, feel free to step in and correct me), once a song is "published" (on a record or CD, for example) anyone can record it for release on another "record". There is no requirement to get permission. That is why the license is called "compulsorary". You need only pay the license fee (many but not all songs are handled by Harry Fox and can be licensed by an individual online for $42 for 500 copies).
This does not apply, however, for other uses of the song, for example in a movie or a commercial.
Often, when a major artist or studio records a song by another artist, they send a demo to the songwriter. But this is courtesy and not mandatory.
In the case of Back Home In Derry, it was Irish singer/songwriter Christy Moore who set the song to the tune of The Wreck. So it was he or his record company that would have been responsible for getting the compulsory license.
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Valerie Magee
Visit my GL fan site at
gordonlightfoot.com and Cathy Cowette's web site at
cathycowette.com