(CNN) -- A judge has ruled that the famous flute riff in Men at Work's Australian rock anthem "Down Under" plagiarized a popular nursery rhyme about a Kookaburra written in 1932.
Thursday's ruling marks the end of a three-year legal battle that started with a trivia question on Australian quiz show "Spicks & Specks."
The show's panelists were asked to name the Australian folksong that could be heard in the popular single which was first released in 1979.
The answer was "Kookaburra," a nursery rhyme written by teacher Marion Sinclair who later entered it into a competition run by the Girl Guides Association of Victoria.
Its popularity among girl guides ensured the song's instant success and 70 years on it can still be heard in Australian schools and playgrounds.
Australian music group Larrikin Publishing bought the copyright to the song in 1990 after Sinclair's death in 1988.
It wasn't until the quiz show in 2007 that Larrikin Managing Director Norman Lurie became aware of the songs' similarities and the potential for a law suit.
On Thursday, Australian Federal Court judge Peter Jacobsen found that the flute riff in "Down Under" did mimic the Kookaburra song.
"I would emphasise that the findings I have made do not amount to a finding that the flute riff is a substantial part of Down Under or that it is the 'hook' of that song," he said.
"Down Under" was composed and performed by Men at Work founding member Colin Hay in 1978. Greg Ham added the flute riff after he joined the band in mid-1979.
According to court documents, Ham added the riff to the song to inject some "Australian flavor." He admitted he had heard the song while growing up in the country in the late 1950s and was "pretty sure" that Kookaburra was in his school's song book.
Judge Jacobsen found that Ham deliberately included the bars from Kookaburra into the flute line, but accepted that Colin Hay didn't realize it was from the nursery rhyme until early in the last decade.
Larrikin is seeking 40 to 60 percent of the royalties earned by "Down Under" in Australia during the last six years, the time limit imposed by Australian law.
"Even if we win, they will still have had a free run for some 20-odd years," Larrikin's lawyer Adam Simpson told CNN.
"It's just really a pity that Marion Sinclair, the lady who wrote it, didn't participate in income from the song when the song was at its height in the early 80s," he added.
Simpson said the company is not at this stage intending to sue overseas for royalties earned by the song outside Australia. "To be honest, such things are theoretically possible but we're keeping it simple," he said.
Experts say the amount of damages payable will be limited by the judge's finding that riff did not amount to the "hook" of the song.
"There's a lot more to 'Down Under' than that flute melody. It's not the main melody and not the main hook and I suppose that in the end will mean that it will be a minor share of the royalties that this publisher can claim now," said Daniel Mullensiefen, co-director of the masters program in Music, Mind and Brain at Goldsmiths University in London.
EMI Songs Australia and EMI Music Publishing are said to be considering appealing the ruling. Another hearing will be held in the next six months to determine royalties owed.
The shorter, more popular version of "Down Under" was released in 1981 in Australia on the band's hugely successful "Business as Usual" album.
By January 1983, the single had hit the top of the music charts in Australia, the U.S., Britain, Canada and several European countries.