It’s true. “Happy Birthday to You” is copyrighted – and brings in something to the tune of $2 million a year to the publishing company, AOL Time Warner. You may have noticed some restaurants do not sing the “Happy Birthday” song to their customers — because they did not pay a fee to the rightsholders for use of the song. How “Happy Birthday” got from its origins as “Good Morning to You,” a nursery school ditty written by two Louisville, Kentucky, sisters, to a licensing juggernaut is a long and sometimes murky story.

On this day, March 4, in 1924, “Happy Birthday to You” made its first appearance in print, in a songbook edited by Robert H. Coleman. The “Happy Birthday” four-line ditty was the second stanza to the “Good Morning to You” song. No definitive knowledge exists of who came up with the “Happy Birthday” lyrics, or put them to the tune of the “Good Morning” song, but there it was.

Mildred J. Hill, who wrote the melody for the song, and her sister Patty Smith, who wrote the “Good Morning” song, copyrighted “Happy Birthday” in 1935 with the Clayton F. Summy Publishing Company. It was already used in a Broadway play, and soon spread to Western Union (their first ever singing telegram) and countless other uses. The song should have went into public domain at the expiration of the 28-year copyright term, but was extended in 1991, and again in the early 2000s, and is now copyrighted at least until 2030.