Wilco lead singer Jeff Tweedy has been with the band since its inception
Jeff Tweedy, lead singer with US band Wilco, has been sued by a former member of the band over unpaid royalties.
Jay Bennett, who played with the band from 1994-2001, is claiming $50,000 (£33,160) for five albums he made with the group, according to court papers.
Bennett, who was a sound engineer and played instruments with the rock act, is also claiming payment for a 2002 documentary in which he appeared.
Tweedy said he has "no idea what these claims are based on".
"I am truly sad it has come to this. I am equally convinced that I have done nothing wrong and that this will be handled fairly and swiftly," added the musician.
Bennett's legal action, filed in Chicago, said he received only "infrequent impartial payments" for his work, amounting to 15% of Wilco's revenues.
"Bennett is entitled to compensation for his services rendered in the form of continuing and perpetual artist royalty payments from Tweedy," court papers stated.
The rock group was formed in 1994, and Tweedy has remained one of the only constant members in a frequently changing line-up.
They won two Grammy Awards in 2005, including best alternative music album for A Ghost Is Born.
In the UK, they are best known as an album act, with chart placings for 1999's Summerteeth and 2002's Yankee Hotel Foxtrot.