Happy birthday is the song that earns the highest royalty rates every year which are sent to Warner / Chappell Music who make millions from licensing the song.
Techdirtpoints out that the song is in public domain as in fact the song's copyright expired many years ago. Happy birthday is believed to be written by the Hill sisters but some evidence suggests that the melody itself predates the sisters and that the owner of the copyright failed to renew it in 1962, establishing further that it is in public domain.
So if this is the case why has no one stood up and challenged Warner Music? Well, because it's just too expensive! Yet, it appears someone is angry enough to try. The creatively named Good Morning to You Productions, a documentary film company planning a film about the song Happy Birthday, has now filed a lawsuit concerning the copyright of Happy Birthday and are seeking to force Warner / Chappell to return the millions of dollars it has collected over the years.
We think this is going to be a very interesting case for the music industry, watch this space!