In closing, three other thoughts come to mind:
1: Having been granted a patent does not mean the government protects
the holder against infringers; rather, the holders must prove
infringement in court. The possibility also exists that the court
action will result in a declaration that the patent is "obvious to one
schooled in the art" and hence not patentable. This is because a patent
is granted on the basis of an opinion by an examinor that the idea is
"not an obvious solution to one schooled in the art". The court can
decide that the examinor was wrong. The only thing the patent proves is
the date claimed by the inventor. Until a patent is sucessfully defended
in a court challenge; it has a debatable value.
2:Around the turn of the century, unbelieveable things were routinely
patented. It seems to be a hobby/cottage industry of the era. Almost
all photographic processes were patented (whether or not they merited
the protection)in one form or another, it is almost impossible to
believe that any technology associated with what we call alt processes
is not in the public domain in some manner. Ferreting out the
information in the maze of old patents is also almost impossible (IMHO).
3. Patents came into being really just to be able to advance technology
on the theory that in order to get one granted, one must disclose ALL
information. After the expiration of the protection, then others could
improve on the technology and advance the "state of the art".
Trade secrets -- now there's something else entirely :-)
John