Returning to topic of the thread:— Is it not at least arguable that certain songs which started life as copyrighted pop songs have become traditional by being traditionally used on specific occasions? Two examples which spring to mind are "Happy birthday to you" [see wiki entry -- apparently, according to some authorities, its © will not expire till next year]; and Liverpool FC's supporters' anthem "You'll never walk alone" which began life in a Rodgers & Hammerstein musical but whose title now surmounts the entrance to Liverpool's Anfield Stadium.

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