THE PRODUCT OF MAN'S MIND
Rand seems to go to great lengths to distance her theory from John Locke's, trying to avoid the idea that mixing one's labor with an unowned resource transforms that resource into owned property. Instead, Rand always speaks of property as the"product of man's mind," not his physical labor.
Now, in most cases, this is a trivial distinction. Obviously, all physical labor is driven by thought; we are not zombies. But the distinction does become relevant when you think of intellectual property: music, stories, movies, etc. Because in a very real sense, Rand sees all property as intellectual property. A poem is as much a product of"intellectual labor" as is a building.
This, I think, helps explain why Objectivists are, among libertarian-minded folks, the ones most inclined toward the legitimacy of intellectual property, while libertarians who get their property theory straight from Locke (or from Locke via Nozick or Rothbard) tend to view"intellectual property" as suspect, as not really property at all, because it lacks any tangible existence.
For my part, I tend to side with the pure Lockeans, but I think Randians may find this an interesting area to explore.