Rudolph Isley has sued his brother Ronald Isley, claiming he improperly registered the trademark for “The Isley Brothers” as a sole individual, excluding him from an asset in a partnership in which they are equal members, Rolling Stone reports, and documents viewed by Pitchfork confirm. The suit seeks a declaration that the mark “The Isley Brothers” is jointly owned by each brother, and an asset in which they “sole and equal members.” Rudolph Isley also asserts that because he is “unaware of the degree to which Ronald exploited the Mark, the licenses and/or other transactions that Ronald entered into” he seeks a judgement forcing Ronald to account for and pay his 50-percent share of the proceeds he’s collected on the trademark. Check out the full lawsuit below.