A federal court ruling that a music publisher had no right to charge royalties for the use of the song, “Happy Birthday,” doesn’t answer all legal questions in the case, Professor Amy Landers said in an article CBS 3/KYW published online.

Publisher Warner/Chappell has for decades charged filmmakers and other TV studios handsome royalties for use of the song, which dates to 1893 and was composed by two sisters who never copyrighted the lyrics.

A federal judge ruled that the copyright filed 80 years ago applied only for specific arrangements of the song.

Landers, director of the Intellectual Property Law Program, said additional legal questions are likely to emerge from the ruling.

“The next step in the case, I understand, will be the court’s determination of whether the royalties that have been collected to date will be returned,” Landers said.