Why did Aaron Ogden sue a man riding a steamboat on a NY waterway?

Aaron Ogden sued Thomas Gibbons for operating a steamboat on a waterway in New York because Ogden held a monopoly license granted by the state to operate steamboats on that route, and he believed Gibbons was infringing on his exclusive rights. The case, Gibbons v. Ogden, ultimately led to a landmark Supreme Court decision affirming the federal government's authority to regulate interstate commerce.