Matthew Fisher had been accused of 'excessive delay' in bringing the case
Procol Harum organist Matthew Fisher has won his long battle to be recognised as co-writer of the band's hit Whiter Shade of Pale.
Law Lords have ruled that Mr Fisher, who claimed he wrote the song's haunting organ melody, is entitled to a share of future royalties.
In 2006, the High Court ruled he was entitled to 40% of the copyright.
But the Court Of Appeal overturned the ruling last year saying he waited too long - 38 years - to bring the case.
As a result, the copyright reverted back to Procol Harum frontman Gary Brooker and lyricist Keith Reid.
On Thursday, the panel of five Law Lords delivered their unanimous ruling which reinstated the 2006 High Court verdict.
The Law Lords said the delay in bringing the case had not caused any harm to the other writers who had, in fact, benefited financially from it.
It was the first time the Law Lords - who heard the case in April - had been asked to rule on a copyright dispute involving a song, according to lawyers.
Mr Fisher, now a computer programmer who lives in Croydon, south London, began legal proceedings at the High Court three years ago.
Lord Justice Mummery said in his Court of Appeal ruling last April that Mr Fisher was "guilty of excessive and inexcusable delay in asserting his claim".
A Whiter Shade of Pale reached number five in the US
"He silently stood by and acquiesced in the defendant's commercial exploitation of the work for 38 years," he added.
But Mr Fisher's counsel, Iain Purvis QC, told the Law Lords in April: "We say for all practical purposes the appeal court confiscated his [Mr Fisher's] share of the copyright and awarded it to the defendants."
He explained that Mr Fisher had taken legal action to be recognised as the joint author and owner of one of the "most famous and popular works of the 20th century, and that he has achieved".
"But secondly, to receive the income to which he says he is entitled as the co-owner of the musical copyright."
Mr Brooker's lawyer Lawrence Abramson had said that overturning the Court of Appeal's ruling would have severe implications for the music industry.
He said it would open up the prospect of countless claims from musicians who felt their contribution to a song had been overlooked in some way, regardless of past contracts.
Whiter Shade of Pale was a number one in the UK for six weeks in 1967 and reached number five in the US.