Rudolph, 83, said in legal docs reviewed by TMZ that Ronald, 81, made business transactions without his knowledge that potentially cost him money.

In the suit, Rudolph told the court that Ronald successfully applied for the trademark to the name The Isley Brothers last summer, and has since collected all of the profits.

Rudolph said that for decades, he and Ronald evenly divided the profits - including multimillion dollar publishing arrangements - prior to recent developments.

Rudolph has requested the judge in the case to audit Ronald's earnings since the change, and have him reimburse him for half of the amount.

The Cincinnati, Ohio-based group initially started out as a quartet with brother Vernon Isley, who died at the age of 13 in a 1955 car accident.

Ronald was pictured performing during the 2022 Essence Festival of Culture at the Louisiana Superdome on July 3, 2022 in New Orleans