"Seeing that the film generated more than 100 million euros in revenue, I do not see why our children, who've worked like animals, should not receive their proper share," said Francis Hartmann, Lucile's father.
Lucile Hartmann and other singers have left the choir since the film was released, in part because of the pressures of frequent concerts and other appearances.
"There's been a shameless exploitation of the children. It was a great adventure that got totally out of control. The film has destroyed the soul, the essence of the choir. It has become totally taken over by show business and money," said Hartmann.
Thierry Levy, a lawyer for Galatee Films, said that parents of the children had accepted the company's contract with the choir. "In full agreement with the parents, the choir judged it best to keep the money for its own activities," he said.
Les Choristes is the story of a music teacher who changes the lives of troubled children with music. It was nominated for an Oscar and won the prize for best music at France's Cesar Awards. The soundtrack album reached number two on the Billboard classical music chart last week.