According to this, there is a dispute about who wrote "Whiter Shade of Pale." So it's off to the courts:
It was always believed that the number, which hit No. 1 in 1967, was written by Procol Harum frontman Gary Brooker and lyricist Keith Reid. But Matthew Fisher, the band's keyboard player, claims he co-wrote the classic and wants a share of the copyright - plus some of the cash from 10 million sales. One expert believes it could have made $1.2 million in royalties.
Fed up with watching the song repeatedly topping best-ever polls, as the years turned to decades, he decided to act. Fisher, now 59 and a computer programmer in South London, said: "It's taken me this long to find a firm of specialist lawyers good enough to take up my fight. But I have been advised not to say anything more."
But on Procol Harum's official website, Brooker said: "A Whiter Shade Of Pale was written by Keith Reid and me before Matthew even joined the band. "I am shocked and dismayed that after Matthew had worked with us quite happily over the course of 40 years without him once alleging that his role on A Whiter Shade Of Pale was anything other than as a musician, it is only now that he claims he recalls writing part of it."
Seems like a lot of trouble for $400K minus lawyers' fees (I'm guessing that would be about $399K), but at least he gets to sully a beloved rock classic.