Yes, that is Rothbard's view. Copyrights are in, but patents are out. However, you can copyright an invention.
When you say brands and logos, you are talking about trademarks. Trademarks are relatively uncontroversial, because when you violate a trademark (e.g., by putting a Nike logo on your shoes), you are committing fraud against the buyer of the shoes. It would be analogous to filling a gold bar with tungsten and selling it as gold.
I have not read Karl Denninger's article in detail yet, but from what I understand, he is a greenbacker and not an Austrian. I will take a look at it, though :)
“With laws shall our land be built up, but with lawlessness laid waste.”