I disagree and do believe there's such a thing as Intellectual Property. You own it in the sense that you have the right to control its use. If I spend 1,000s of hours researching a subject, I have a right to control how these products of my labor are used. Someone anonymous crank shouldn't be allowed to take all the output of this effort, print it in a book, and then sell it.
Just to elaborate on this a bit more. What is "ownership"? Ultimately, God owns everything. So our ownership is somewhat relative and reduces to a right to control and benefit from something (as opposed to someone else having that right). If I own some land, that means, I have the right to farm it, develop it, etc. If I own a car, then I have the right to drive it. Same notion applies to immaterial things that can be "owned". With regard to material things, the possession or control we have over it is more tangible, but the issue is the right to control something, and not simply
de facto control. Of course, you can't "own" or "patent" something that is not proprietary (I can't own the notion that 2+2=4, since it's common knowledge). But there is such a thing as "proprietary" knowledge (notice that proprietary and property derive from the same Latin root word). If I came up with a unique idea, especially as a result of the fruits of my labor, hours of research, experimentation, and other labor, that would be my intellectual property, and it would be wrong for someone else to take those ideas and benefit from them. Similarly, if I worked in order to build some contraption to help me, say, farm my land, I would own it, and someone else doesn't have the right to come along an appropriate it for their use.