Washington: A lawsuit over who owns the copyright to ‘Happy Birthday to You’ has been settled, bringing to an end a two-year legal battle over what is said to be the most widely sung tune in the English language.

The settlement announced Wednesday came days before a trial in California that was to determine whether the song should be part of the public domain.

A US judge had ruled in September that Warner/Chappell Music, the global publishing arm of Warner Music, never had the right to charge for for-profit use of the song.

Nor did any of the other companies that had collected royalties since the copyright was first granted in 1935, the judge ruled, dismissing the Warner copyright claim.

Terms of the settlement were not disclosed, but US media reports suggested that based on the September ruling, the lyrics to the song will now be free for anyone to use.

The lawsuit was filed by a group of filmmakers who argued that the song should be in the public domain.

The song was written in 1893 by Patty Smith Hill, a Kentucky kindergarten teacher, and her sister, Mildred J. Hill, who titled it  ‘Good Morning To All.’

The sisters published it in a book of songs children and assigned the copyright to their publisher, Clayton F. Summy Co, in exchange for a cut of the sales.

The ‘Happy Birthday’ lyrics were added later, and since then the song’s road to copyright has been windy.

Warner had been enforcing rights to ‘Happy Birthday’ since 1988, when it purchased Birch Tree Group, the successor to Summy, the Los Angeles Times reported.

It said that by some estimates, Warner collected as much $2 million a year in royalties.

On Wednesday, Judge George King wrote that the court had been advised that the parties ‘have agreed to settle this case.’

The LA Times quoted a person with knowledge of the settlement as saying the entire case addressing the validity of the copyright and potential damages has been resolved and that there would be no further appeals.