NEW YORK -- No matter who's singing it, or what the setting is, or what else is being communicated aside from "Happy Birthday," because it is copyrighted, every time the song is performed in public someone is supposed to pay the publisher -- Warner/Chappell.
The copyright is the reason why waiters and waitresses often sing their own versions of a birthday song.
"I think it's a joke because it's the people's song," said filmmaker Jenn Nelson.
When Nelson wanted to use "Happy Birthday" in her documentary about the song, "Happy Birthday Movie," the publisher said it would cost $1,500. She sued, instead, saying the song is in the public domain and anyone could sing it for free.
Nelson could have forked over the money and not dealt with the legal fight, but she decided to pursue it.
"The problem is that, I think, people have been apathetic," she said.
The melody was written in 1893 by sisters Mildred and Patty Hill as a song for kindergartners.
Over the years "Good Morning to You" morphed into "Happy Birthday to You," with the publisher claiming a copyright for a song that produces at least $2 million in royalties each year.
Law professor Robert Brauneis is an expert on the song.
"The question of when, and where, and by whom the 'Happy Birthday' lyrics were added is a question that's up in the air, which leads to all these issues" said Brauneis.
The "issues" might be decided in a few weeks when a federal judge could really give one side or the other something to sing about.