The title of this post refers to "intellectual property". There is no such thing. There are patents, copyrights, and trademarks. But none of these is property. If they were we would not need a special part of the US Constitution to deal with these things (Article 1, Section 8). Because none of this is "property" it is not covered by property law.
And that's the problem. Patents, copyrights, and trademarks exist to further innovation. They represent a monopoly limited in time and held by the innovator who created the thing that is patentable, copyrightable, or tradmarkable. But when we treat those temporary monopolies as property that can be bought and sold, inherited and used as collateral, we have destroyed the impetus to innovation and replaced it with an impetus to profit even at the peril of innovation.
And so we have the ridiculous spectacle of a copyright extended and extended ... even beyond the lifetime of the innovator. How does a copyright encourage creativity in a dead person? The solution to all of this is simply to return to the original short terms of these monopolies and not to allow property law, buying and selling of rights, to insert it's corrupting hand into the crucible of creativity.