The Spice Girls' songwriters, Richard Stannard and Matthew Rowbottom, who co-wrote and produced the number one hit Wannabe, are facing an action in the High Court.
They are being sued by a solicitor who says he gave up his job to manage them.
In his writ, Ian Clifford, of London NW6, claims that Stannard and Rowbottom agreed to pay him 20 per cent of their earnings when he agreed to quit his job to devote his time to managing them.
But he says that last July they ended the agreement without notice, and refused to pay him commission or expenses.
Clifford, who was a solicitor in the music department of the Simkins Partnership, is seeking damages for breach of contract and a declaration that he is entitled to 20 per cent of Stannard and Rowbottom's earnings for the period that he was managing them.
He claims his services were terminated at the very time when the Spice Girls' recording of Wannabe reached number one in the UK.
Wannabe is one of five songs co-written and produced by Stannard and Rowbottom and recorded by the group.
Their album, Spice, which includes four Stannard and Rowbottom co-written songs, has since sold 2.7 million copies in the UK.
Four singles from the album, three of which were co-written and produced by the pair, also reached number one.
Clifford says that the amount that was paid to him by Stannard and Rowbottom was £57,099.91. But at a conservative estimate he claims he is entitled to some £500,000.
Clifford's claim is being handled by Clintons, and Russells is representing Stannard and Rowbottom.