"The distinction between the music and the lyrics as copyrightable elements is critical in this case because both Parties agree that the Happy Birthday melody was borrowed from Good Morning and entered the public domain a long time ago. The Parties disagree only about the status of the Happy Birthday lyrics. Defendants contend, in brief, that the Hill sisters authored the lyrics to Happy Birthday around the turn of the last century, held onto the common law rights for several decades, and then transferred them to Summy Co., which published and registered them for a federal copyright in 1935. Plaintiffs challenge nearly every aspect of this narrative. They argue that the lyrics may have been written by someone else, the common law copyrights in the lyrics were lost due to general publication or abandonment before the lyrics were published, and the rights were never transferred to Summy Co."
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