This is a weird way to talk about IP and rent. Is profit from IP necessarily rent? The problem is that "rent" is defined as "profits earned above what would be earned in a competitive market," but "competitive market" isn't well-defined until you define a system of rights (namely property rights). Markets are just systems of trade, and "trade" is the exchange of ownership.
Thus, an action which most of us believe constitutes a violation of property rights (e.g. I buy a laptop and someone takes it from a cafe without my permission and then sells it to a third party) is not "trade in a competitive market." So is an IP right a legitimate instance of ownership? Many people (and most Western legal systems) consider it to be so. There are also people who don't consider it to be so, pointing out differences between physical property and intellectual property. And, to be clear, there are people who don't even accept certain aspects of well-accepted physical property rights.