The Black Eyed Peas are being sued by funk pioneer George Clinton, who claims the band used elements of his 1979 song (Not Just) Knee Deep in remixes of their song Shut Up.
The song first appeared on the group's 2003 album Elephunk, and it released Shut Up Remix the same year.
It was also used in another remix included on the deluxe edition of the Peas' 2009 release, The E.N.D., according to Clinton's complaint.
Clinton says he never granted permission for the use of his music, and he is seeking copyright infringement damages and an injunction to block further sales of the remixes.
His lawsuit also names as defendants will.i.am and Fergie, the two highest-profile members of Black Eyed Peas. He is also suing the group's label, Universal Music Group.
A representative for the band's lawyer said he doesn't comment on client issues. A phone message left for Universal Music Group was not immediately returned.
Clinton claims producers tried to license (Not Just) Knee Deep in 2009, but he refused. He claims his signature was forged on a release form later provided to his lawyers and that he has never been paid royalties on the remixes.
The musician previously obtained the rights to his music after suing his label.