Filmmakers fighting “Happy Birthday” copyright find their “smoking gun”

It's been two years since filmmakers making a documentary about the song "Happy Birthday" filed a lawsuit claiming that the song shouldn't be under copyright. Now, they have filed (PDF) what they say is "proverbial smoking-gun evidence" that should cause the judge to rule in their favor. The "smoking gun" is a 1927 version of the "Happy Birthday" lyrics, predating Warner/Chappell's 1935 copyright by eight years.

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