Newswise — The long copyright battle over the "Happy Birthday" song - the world's most popular melody - may be over in the wake of a federal court ruling stating the song is a part of public domain, but the mystery behind the song's origin continues to develop.

The only known manuscript of Louisville native Mildred Hill’s song “Good Morning to All,” which evolved into the world-famous “Happy Birthday” song, was recently found in an abandoned file cabinet at the University of Louisville music library - but with a twist.

The first page of the songbook, which holds the answers to when the composition was written or whether the "Happy Birthday" melody was the original or revised version, is missing.

The manuscript was discovered by library director James Procell, who immediately noticed that the first page was missing.

“We’re glad this court case is resolved and the world may now freely enjoy the Hill sisters’ famous song,” said Procell. “But for us, mysteries remain. Do we have the original version of the song, or was Ms. Hill somehow unhappy with the published version and this represents a revision of the song? And of course, we’re also still wondering where page one might be.”

Some differences from the familiar “Happy Birthday” tune are noticeable. The song is written in a different key, and has a slightly different melody, though the rhythm and words remain the same as the published version.

For more information or to set up a media interview, contact Matt Lambert at 502-852-7542 or [email protected].