Impairment

Just because the patent may have unlimited life (I have always understood that patents are granted for a maximum period of 16 years … but I could be wrong) doesn’t mean that the market for the patented product will always exist

Surely it’s the condition of the market for the product that determines the useful life and the value of the patent

And then there’s this from Wikipedia:

“Significant international harmonisation of patent terms across national laws was provided in the 1990s by the implementation of the WTO’s Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPs Agreement).

Article 33 of the TRIPs Agreement provides that the

“The term of protection available [for patents] shall not end before the expiration of a period of twenty years counted from the filing date”

So the concept of a patent with an unlimited life seems unlikely … and there’s your answer

OK?