As a former copyright activist, we used to hold up "Happy Birthday To You" as the quintessential example of everyday activities that were copyright infringements, like when Lawrence Lessig went through the formalities to perform the song at the anniversary of Free Culture [1].

Yet the questionable legitimacy of the "Happy Birthday To You" copyright claim is something I only recently started to hear about, first from Ben Sisto's Ignite NYC talk [2] and then again from several other copyright activist friends.

While even litigating the validity of Warner's copyright over "Happy Birthday" would be a symbolic victory for copyright activists, it likely wouldn't get very far. And let's not forget that Congress could be moved to pass a law granting "Happy Birthday" its own copyright exemption in response to the actions of a court.

[1]: http://www.wired.com/wired/archive/13.07/posts.html?pg=7 [2]: http://www.youtube.com/watch?v=mkUFlZ05EiI