"The Patent and Trademark Office has now made clear that
its newly developed position on patentable subject matter
will invalidate many and perhaps most software patents,
including pioneering patent claims to such innovators as
Google, Inc.
In a series of cases including In re Nuijten, In re Comiskey
and In re Bilski, the Patent and Trademark Office has argued
in favor of imposing new restrictions on the scope of
patentable subject matter set forth by Congress in article
101 of the Patent Act.
In the most recent of these three — the currently pending
en banc Bilski appeal — the Office takes the position that
process inventions generally are unpatentable unless they
'result in a physical transformation of an article' or are
'tied to a particular machine.'"