Blow out the candles, sweep up that wrapping paper, and most of all, consider for a moment as to whether  all those lovely money gifts will go away? The plaintiffs in a much-publicized suit say they have found new, conclusive evidence that will help them persuade a federal judge to rain on Warner/Chappell Music Inc.’s party, specifically to end its claim to hold the lucrative copyright to what be one of the world’s most performed tunes: the Happy Birthday song.

The plaintiffs have filed an ex parte application to submit new evidence that they assert Warner “mistakenly” had failed to hand over during discovery. Based on this trove of historic material, they also have sought summary judgment to halt Warner’s copyright claims and reports say a decision may come very soon.

As the world awaits U.S. District Judge George King’s ruling on these matters in Los Angeles, let’s unwrap what may become a most unhappy matter for music publishing powerhouse.

Two years ago, this blog and many others covered the copyright case that captured global attention because it asked,  Does Warner-Chappell really hold a valid copyright on  the birthday tune? Warner said it had such rights, without a doubt, when filmmaker Jennifer Nelson sought to make a documentary on the tune’s history.

Because her film would include a scene in which the song is performed, she and her production company sought permission for its rights and was told she would have to pay for a $1,500 synchronization license. She did but later followed up with a class-action lawsuit, in which her attorneys detailed the songs’s extensive publishing history and asserting because of the dates involved, Happy Birthday, had, in fact, entered into the public domain.

Warner/Chappell disagreed.

Discovery in the case ensued. And it turns out, according to the plaintiff’s filings, Warner/Chappell asserted it had  “mistakenly” left out some key materials in handing over some important files last year  Good Morning to You Productions, Nelson’s company and the plaintiffs in this case.

What’s the key new evidence uncovered? The plaintiffs say they can show that the birthday song was published in the fourth edition of “The Everyday Song Book,” back in 1922.

Works published in 1922 were subject to the 1909 Copyright Act, which stated that holders to keep their protections had to include a copyright mark on their work, as well as the year of first publication and the author’s name. Failure to follow these requirement would send works into the public domain.

The original owners of the birthday song published it in “The Everyday Song Book,” without the required mark, notice of protection, date of publication, or author credit, the plaintiffs say.

Uh, oh. Further, they say this publication occurred 93 years ago and the song would have entered public domain by 1950, if the copyright were not renewed, which it was not.

Even if the copyright had been renewed,  the Sony Bono Act would have protected it only until the end of 1997.

So in 1993, how could Warner/Chappell have changed so many parties for uses of the celebratory ditty? Warner finds itself potentially in a interesting position, since it has said it has collected birthday song royalties since 1988, arguably 66 years after it had been placed in the public domain.