When we start talking about "intellectual property", we need to make sure that everyone knows what we are talking about.
That means we need to make sure we are not talking in implicit oxymoron, such as when one party to the conversation misunderstands how far property rights can extend.
It is quite possible to temporarily own mindshare, or to be the primary public agent of a meme. That's usually the purpose of modern advertising, unfortunately.
That's not what intellectual property is all about, although some people seem to be confused and thinking in that direction. That's not the only error, but it is one that you should check:
Are you wanting a patent or copyright on something the other guy is not going to be able to get out of his mind?
This is similar to having a patent (in the old sense) on tobacco or coffee or some other pseudo-staple. Or tea. (In case you missed the reference, I'm referring to the Boston Tea Party.)
US-Americans should remember where that kind of commercial behavior leads.
It should be obvious that one cannot own what is in another person's mind in the same way as one can own a home and rent it out to another person.
Sure, you can call the police and take things to court and stuff, but you can't prove that the other guys is thinking the "owned" property, and you can't be sure that he is not. That means you end up hanging real punishments on a person's word.
There is no surer way to pervert a lot of people's intent to be honest than to force them to choose between going to jail and lying about their thoughts. Sure, some serious fanatics would choose jail to declare publicly that their thoughts will not be coerced. Some others might choose jail for the free lunch.
But the population at large will ultimately choose duplicity in such a situation. That means, if you attempt to control thoughts by law, the law works against itself. Unless you are so cynical as to be trying to destroy the law by such tricks, that would be counter to your purpose.
That is one of the fundamental reasons for governments to acknowledge and respect freedom of thought. To do otherwise is to be self-destructive, and governments should not be programming themselves to self-destruct.
So, when we talk about intellectual property, we don't want to talk about thought control, okay? We don't want to talk about it in any hidden way, either.
Intellectual property needs to be re-named. The subject is material that takes intellectual effort to produce, but it is not but it is the effort, not the subject, that is intellectual. A more relevant appellation would be "intangible", but "intangible property" as a term seems to have been rejected. (Possibly because those who want to claim this stuff as property recognize that it would get them far less sympathy.)
Moreover, it is neither the effort nor the product of the effort that is the property. What we call intellectual property is a lien against a piece of the market commons. It is a temporary right to control production and/or distribution of a physical or literary/artistic product, or the trademark under which the production and distribution activities occurs.
As a property, if it can be bought and sold, it would have to be bought and sold in ways similar to stocks and bonds. But it has one huge difference. It has a built-in termination. (There is a reason for that, and it relates to the freedoms issue above, but I don't want to go there in this rant. In another rant, yes, but not this one.)
(Israel apparently had a built-in termination clause on certain kinds of commercial activities. It was called the Jubilee.)
It is not a property, really, it is a lien. A temporary lien. It's supposed to be that way.
Patents, copyrights, trademarks, all these things that are forced under the false rubric of "intellectual property", each one is separate. They can be combined in effect, but they are separate.
What they have in common is a monopoly principle. They are, indeed, monopolies, and that is one of the reason certain people who don't know how to compete on quality and service in a free market want them to own them.
Unlimited monopolies work against every government that grants them. Not just democracies, not just governments that recognize individual freedom, every government. If you give a person an unlimited patent on roads, it won't be long until that person or his successor in interest is holding the roads as ransom against the government, through the public interest, if not directly.
Likewise any staple food, or any food-like product that can be coerced into staple status. A history book with a copyright of too long a term could be made popular enough among educators to be considered indispensable, and then the printer producing that book has a wedge against the public interest.
If a patented memory circuit can be made part of a standard that gets adopted everywhere, it can be used as a weapon against all other memory manufacturers.
If a common term (like "windows" was a common technical term just a couple of decades ago) is allowed to be trademarked, and the trademark rights are allowed to be asserted in broad ways, the owner of the trademark can use the trademark as a wedge and a club against an entire industry, an evil that extends as far as the trademark can be asserted.
And so forth.
So, let's get this straight. "Intellectual property" is a euphemism for monopoly.
Now, do you still want to argue for making them unlimited?