It's the riff that has haunted guitar shops and the final hours of bad house parties since 1971.
Now it turns out 'Stairway To Heaven' – the most famous song ever recorded by Led Zeppelin the greatest rock band of all time – may have been copied from somewhere else.
A US court has ruled that there is "substantial" similarities between the firs two minutes of 'Stairway' and an instrumental by the band Spirit, who shared a bill with Zep during the 60s.
Rock folklore has it that the haunting song with four-chord progression every budding guitarist learns after they've mastered 'Smoke On The Water' by Deep Purple was written by Robert Plant and Jimmy Page in a remote cottage Wales, presumably while under the influence of a cocktail of mind-bending substances.
But Michael Skidmore, a trustee for the late Spirit guitarist Randy Wolfe, has suggested his client should be given a writing credit on the track.
US district judge Gary Klausner said "While it is true that a descending chromatic four-chord progression is a common convention that abounds in the music industry, the similarities here transcend this core structure" Judge Klausner ruled.
"What remains is a subjective assessment of the 'concept and feel' of two works... a task no more suitable for a judge than for a jury."
The trail has been scheduled for 10 May, but in the meantime you can make your own mind up: