Family members of the Gap Band have filed a lawsuit against music conglomerate BMG for allegedly failing to pay royalties from Mark Ronson and Bruno Mars’ hit “Uptown Funk,” reports NME.

The suit claims that BMG has yet to compensate Ronnie Wilson’s widow Linda, Robert’s daughter Robin and LaTina, as well as other family members for their shares of the song. Charlie Wilson, the third and only living member of the Gap Band, was not named in the lawsuit.

“This case is yet another chapter in a long-running series of disputes involving the smash musical composition and sound recording "Uptown Funk," originally credited to Bruno Mars and Mark Ronson," the suit reads. "Plaintiffs have monetary interests in ‘Uptown Funk’ owing to its incorporation of the musical composition ‘Oops Upside Your Head.'"

“In this installment of the ongoing ‘Uptown Funk’ saga, defendant music publisher BMG Rights Management has failed and refused to pay plaintiffs or account to them for royalties they are obligated to pay plaintiffs pursuant to a written contract as co-writers of ‘Uptown Funk,' the suit continued.

Michael Steger, the Wilson's family attorney said they have worked for several years to receive "proper credit and royalties" for the song’s usage and are “left with no choice but to pursue litigation to protect their rights.”

“Despite its obligations to account for and pay to plaintiffs their share of all income received from the ‘Uptown Funk’ musical composition, BMG has refused and failed to provide either the funds due to plaintiffs or an accounting despite plaintiffs’ repeated demands,” the Wilson family allege.

In 2015, an agreement was reached in which Robert and Ronnie Wilson were listed as co-writers of “Uptown Funk” in an attempt to avoid a future copyright lawsuit. According to the agreement, the Wilson brothers received music publishing rights and 3.4 percent of the copyright for Ronson's and Mars' sample of “Oops Upside Your Head.” 

A massive global hit, "Uptown Funk" held the number one spot on the Billboard Hot 100 for 14 weeks; it was also certified 11 times platinum, and won a Grammy for Record of the Year in 2015.