Years ago I read the book "Radical Markets" by Glenn Weyl and Richard Posner. One of the ideas was a system of property tax system in which you pay property tax based on a property value which you get to declare (rather than some assessment by a third-party or government agency). The catch is that you are required to sell to anyone who offers your declared value. So a bit like a land value tax but fully general (can be applied to anything) and also sidestepping the issue of how to actually determine the the "value" in land value.
While this would pose obvious practical problems as a system for property taxes, it seems like it might actually be a good system for patent taxes. Basically, you should have a to pay a patent tax to hold a patent. You can declare whatever value you want on the patent but have to also be willing to sell the patent at that declared value (or maybe just license it). I haven't thought it through really (just an idle thought) it certainly seems like it would basically destroy the business model of "patent trolls" and curb the practice of major tech players accumulating a huge portfolio of dubious patents as a cudgel they can threaten smaller competitors with.
While this would pose obvious practical problems as a system for property taxes, it seems like it might actually be a good system for patent taxes. Basically, you should have a to pay a patent tax to hold a patent. You can declare whatever value you want on the patent but have to also be willing to sell the patent at that declared value (or maybe just license it). I haven't thought it through really (just an idle thought) it certainly seems like it would basically destroy the business model of "patent trolls" and curb the practice of major tech players accumulating a huge portfolio of dubious patents as a cudgel they can threaten smaller competitors with.