Rudolph Isley Sues Brother Ronald Isley Over Rights to 'The Isley Brothers' Trademark

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The Isley Brothers' Rudolph Isley has filed suit against his brother and former bandmate Ronald, alleging that Ronald went behind his back and registered The Isley Brothers trademark on his own, when it is actually "jointly owned" by them both.

Rudolph, 83, is a founding member of the group, though he stopped performing with The Isley Brothers in 1989 due to poor health and the death of his brother and bandmate O'Kelly Isley, according to the complaint.

In documents filed Monday in Illinois federal court and obtained by PEOPLE, Rudolph says he, Ronald and O'Kelly — the band's founding members — operated the group "as a common-law partnership," sharing all expenses, profits and control of the business.

When O'Kelly died in 1986, his interests were passed equally to Rudolph and Ronald, 81, with each receiving a 50% share of ownership in the group and in the Isley Brothers trademark, according to the complaint. Over the years, the two have maintained that even split, and neither brother has "the authority to enter into deals concerning the group or the exploitation of the [trademark] without consent of the other party," the complaint states.

Still, Rudolph claims that in November 2021, Ronald filed to register exclusive rights on the trademark in his own personal name "for visual recordings and audiovisual recordings featuring music" without telling Rudolph, and had his application approved and registered by the U.S. Patent and Trademark Office in August 2022.

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Both Ronald's application and registration "claim exclusive rights in the [trademark] dating back to a priority date of 1954, when the Brothers first formed the group," according to the complaint, and Rudolph is seeking a declaratory judgment and related relief that says he and Ronald actually own the trademark together.

He is also seeking a rundown of all the transactions completed and revenues earned "through Ronald's improper registration," and wants his brother to pay him his "rightful 50% share of all results and proceeds" he's earned since the registration.

Rudolph's filing also includes a letter written in January by Ronald's attorneys, which claims that Ronald "set up his own corporate entity to do business solely related to his own musical/entertainment career" as Ron Isley.

Ronald and Ernie Isley are the only current members of The Isley Brothers. Though Rudolph left in the '80s, he has remained active in promoting and managing the group's properties, according to the complaint, including a multi-million dollar music publishing deal in 2018, and more recently, negotiation of a licensing deal that saw "Shout" used in a 2023 Super Bowl commercial.

Still, the letter from Ronald's attorneys alleges that Rudolph's argument that he and Ronald have always shared 50% ownership cannot be true, as there have always been more than two members of the group.

"The owner of a trademark is the person who applies the mark to the services that they perform, and who is actually and actively using the mark in commerce during or near the time of registration," the letter says. "Our research shows that Rudolph Isley has not used the mark or been part of The Isley Brothers brand since 1986 and has not performed with The Isley Brothers since the death of their brother O'Kelly Isley. Even if Rudolph had applied for a Trademark while he was using the mark in commerce, it would eventually have become abandoned as abandonment of a trademark occurs when the owner ceases from using the mark in commerce for at least three years."

The letter continues, noting that Ronald is only selling merch that pertains to him and Ernie Isley, and that he only wants to incorporate Rudolph into the business "for the years that Rudolph was a working member" of the band.

Attorneys for both Rudolph and Ronald did not immediately respond to PEOPLE's request for comment.