One more thing about patent claims. If one is invalidated or not
granted because of prior art, or one of the other objections that can sink a
patent claim, that does not kill the whole thing. The claims are separable in
a legal sense. Thus a rather general claim, usually one of the early ones, may
be overturned as being too broad, but the specific instances that refer to it
may still stand. Patent applications are often written with general claims of
somewhat questionable overgenerality because those claims serve as the logical
foundation for the more specific ones that follow. It is not uncommon during
the examination process for the general claims to get whittled down to a subset
of the more specific ones.
It is a deeply ingrained habit of patent lawyers to write the claims as
generally as they can without insulting the intelligence of the examiners. If
an overly general claim is granted, they drink an extra round at the
celebration party.
Mark Holm