Public domain as a right of humanity
The problem, as I see, is not the rights of man. Is one of vested rights. Given the significant difference between legal systems, on most roman tradition systems, a right of free use subject to a certain delay of time is a vested right albeit not immediately enforceable (as to the free use). All the means to preserve the flow and end of time as assured at moment zero are however allowed.
Once a exclusive right is acquired, subject to a definite time, all the persons excluded from the enjoyment by the acquisition have a rightful expectation of free use when the time expires. If such expectation is assimilable to an easement or a vested right is certainly a question of jurisdiction. But only so.
I notice that in Sears, Roebuck & Co. V. Stiffel Co., 376 U.S. 225 (1964), the court said:
"During that period of time no one may make, use, or sell the patented product without the patentee's authority. But in rewarding useful invention, the "rights and welfare of the community must be fairly dealt with and effectually guarded. To that end the prerequisites to obtaining a patent are strictly observed, and when the patent has issued the limitations on its exercise are equally strictly enforced. (...)
Ø when the patent expires the monopoly created by it expires, too, and the right to make the article - including the right to make it in precisely the shape it carried when patented - passes to the public.