According to the 1998 Guinness World Records, "Happy Birthday to You" is the most recognized song in the English language. The melody of "Happy Birthday to You" comes from the song "Good Morning to All," which has been attributed to American siblings Patty Hill and Mildred J. Hill who wrote the melody in 1893. Patty was a kindergarten principal in Louisville, Kentucky; her sister Mildred was a pianist and composer. The Summy Company registered for copyright in 1935, crediting the lyrics to authors Preston Ware Orem and Mrs. R.R. Forman. In 1988, Warner/Chappell Music purchased the company owning the copyright for $25 million, with the value of "Happy Birthday" estimated at $5 million. Based on the 1935 copyright registration, Warner claims that the United States copyright will not expire until 2030, and that unauthorized public performances of the song infringe the copyright. Warner Chappell, has zealously enforced its right to royalties and earns an estimated $2 million a year from Happy Birthday.

Two years ago, film-makers working on a documentary about the "Happy Birthday" song filed a lawsuit claiming the song should not be under copyright, after being told they would have to pay $1,500 to use it in their film. In a class action lawsuit filed in 2013, Good Morning to You Productions claimed that Warner/Chappell had collected "millions of dollars" in licensing fees for the song even though its origins are disputed.

A University of Louisville librarian discovered a manuscript that has caused more doubt about Warner's copyright claims to "Happy Birthday to You." The manuscript and other papers were donated to the library in the 1950s by a friend of the Hill sisters, but were not catalogued and remained hidden in its archives. Included in the documents was the 15th edition of a book entitled "The Everyday Song Book," published in 1927, which contains both the lyrics and the melody to "Happy Birthday." Officials at the university said there was no copyright notice attached to the manuscript, although the cover page was missing.

Lawyers representing Good Morning to You Productions then tried to find earlier editions of the book and came across an edition published in 1922 in the archives belonging to the University of Pittsburgh. The plaintiffs argued in a court filing this week that the copyright for the song entered the public domain when both the lyrics and melody of the song were published in "The Everyday Song Book" without notice of copyright. Under the 1909 Act, works published without notice entered the public domain upon publication.

Click HERE to read the plaintiff's application to have the Court consider the newly found evidence.

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