CNN reports that Fleetwood Mac singer and guitarist Lindsey Buckingham is suing the band.
Buckingham claims he lost an estimated $12 million in upcoming tour proceeds.
He is suing Stevie Nicks, Christine McVie, John McVie and Mick Fleetwood.
He alleges a breach of fiduciary duty and breach of oral contract.
This comes after Buckingham was involuntarily expelled from the band in January.
Founded in 1967 by Peter Green, the band was named after Mick Fleetwood and John McVie.
Green left in 1969, and Buckingham joined in 1974, the same year as Stevie Nicks.
Buckingham wrote some of the band's most well-known songs, including "Go Your Own Way."
While it's not clear what led to his exit, his suit outlines debates about touring schedules.