It is not the whole point of patents. They at least ostensibly exist as a trade to eventually make the invention enter the public domain. Per Wikipedia:
> In accordance with the original definition of the term "patent", patents are intended to facilitate and encourage disclosure of innovations into the public domain for the common good
The idea is that to avoid companies keeping the details of inventions hidden indefinitely using trade secrets, the embargo period is set up as an incentive to disclose the idea. This is an incredibly important part of the entire social contract of patents. Maintaining a complicated legal apparatus (courts, patent offices, etc.) to defend and enforce these legal monopolies is expensive and is paid through public funds. Thus a public good is expected in return. A system that allows the most important inventions to stay locked up forever seems to go against the spirit of this entirely. Perhaps you think that this has its own merit, but it is certainly not the intended purpose of the patent system.
An exponentially growing annual fee is also a great way to fund public goods.
For example, if you increment the exponent every three years, a $20 initial fee would cost half a billion dollars annually after 20 years. That buys a lot of school supplies.
> In accordance with the original definition of the term "patent", patents are intended to facilitate and encourage disclosure of innovations into the public domain for the common good
The idea is that to avoid companies keeping the details of inventions hidden indefinitely using trade secrets, the embargo period is set up as an incentive to disclose the idea. This is an incredibly important part of the entire social contract of patents. Maintaining a complicated legal apparatus (courts, patent offices, etc.) to defend and enforce these legal monopolies is expensive and is paid through public funds. Thus a public good is expected in return. A system that allows the most important inventions to stay locked up forever seems to go against the spirit of this entirely. Perhaps you think that this has its own merit, but it is certainly not the intended purpose of the patent system.