NEW YORK • The copyright to the world's most popular song, Happy Birthday To You, has been in dispute for decades, but if an agreement by Warner/Chappell Music to pay US$14 million (S$19.5 million) to end a lawsuit over the song is approved by a United States court, it will be free for all to use as they please.

The settlement, unveiled in the federal court in Los Angeles on Monday, would eliminate the music publisher's claimed ownership of the song.

It also specifies that once the settlement is approved by the court, the song will be in the public domain. A hearing is scheduled for March 14.

A group of independent artists and film-makers filed a class- action lawsuit in 2013 against Warner/ Chappell, the music publishing arm of privately held Warner Music Group.

In a court filing on Monday, the group hailed the settlement as "unquestionably an excellent result".

"We are pleased to bring this matter to resolution," a Warner/ Chappell spokesman said in a statement on Tuesday.

The settlement said that US$14 million to US$16.5 million represented the estimated amount that Warner/Chappell would have earned through 2030, the earliest date at which its disputed copyright would end.

The plaintiffs' lawyers would pocket one-third of the settlement money - US$4.6 million - with the rest divided among people who had paid to use Happy Birthday To You back to 1949.

In September, Chief US District Judge George King ruled that Warner/Chappell did not have a valid copyright claim to the song's lyrics.

The case garnered attention from around the world not only because the tune is so commonly performed, but also because many people were not aware it was still under copyright, let alone purportedly owned by a major corporation.

People who sing Happy Birthday in their homes or at private gatherings have typically never been at risk of a lawsuit.

But when the song was used for commercial purposes, such as in films, Warner demanded payment and took in an estimated US$2 million in royalties for such uses each year.

The song has a complicated history reaching back to the 1893 publication of Good Morning To All, a children's song written by a Kentucky woman named Mildred Hill and her sister, Patty. That melody eventually came to be sung with the familiar Happy Birthday lyrics.

Warner contended its copyright to the lyrics came through the Hill sisters' publisher that it had acquired.

But judge King said that the publisher never obtained the rights to the lyrics and so neither did Warner.

REUTERS, AGENCE FRANCE-PRESSE