'Intellectual Property' is not a legal classification, and shouldn't be. Patents, Trademarks, Copyrights, and looser-defined 'trade secrets' all have distinct purposes. Saying "Intellectual Property" when you mean "Trademark" gives the impression that the holder has all kinds of legal protections which don't actually apply.
Over the long term, there's danger that legal theories will change to further expand the rights of corporate publishers.
> 'Intellectual Property' is not a legal classification, and shouldn't be.
Intellectual Property isn't a classification defined in law, but it is an analytic classification used in law, the same way that various other subcategories of "property" are, to discuss related protections.
∀X : X ∈ { Copyright, Trademark, Patent, ... }, X ⊂ Intellectual Property ⊂ Intangible Personal Property ⊂ Personal Property ⊂ Property.
Those are not true subsets like you suggest. Consider that moral rights, which fall under intellectual property law, don't fit into the "property" category. For example, the "right [of the author] to prevent the destruction of a work of art if it is of 'recognized stature'" is not something which is true of anything I know of outside of creative works.
In German law, the inventor of a patent has the right to a share of the profit even if developed as an employee of the company making the profit; again, something not shared with tangible property.
I think of the relationship between "intellectual property" and "property" is more akin to "Pluto is a dwarf planet, but it's not a planet."
> Consider that moral rights, which fall under intellectual property law, don't fit into the "property" category.
Moral rights absolutely fall under the property category.
> For example, the "right [of the author] to prevent the destruction of a work of art if it is of 'recognized stature'" is not something which is true of anything I know of outside of creative works.
Well, yes, the fact that element x is an element of set A and set A is a subset of set B, and set C is a subset of set B does not imply that x is an element of set C.
The whole point of named subsets of property (and, named subsets as analytic categories in general) is that the names come from features that are shared within the named subset that are distinct from other subsets in the broader set. So, yes, Copyright has features that are dissimilar to Patent or Trademark, IP generally has features that are dissimilar to other intangible personal property, intangible personal property has features that are dissimilar to tangible personal property, and personal property generally has features that are dissimilar to real property.
You are right. My examples were not valid counter examples.
I think of a property right as something which is transferable. The two examples I gave were of rights that were not transferable. However, if "Personal Property" also includes non-transferable rights, then there's no conflict.
As a clear counter-counter-example of why my counter-example is wrong, tenancy rights are part of real property law, and may or may not include succession rights.
My comment then transforms to the (trivial) observation that intellectual property ⊄ real property.
Over the long term, there's danger that legal theories will change to further expand the rights of corporate publishers.