On the (un)patentability of business methods

Interesting decision about the (un)patentability of business methods, also retracing the history of patent protection, and showing its (frequently overseen) limits and bounderies.
The Court of Appeal for the Federal Circuit asserts that
"It is thus clear that the present statute does not allow patents to be issued on particular business systems—such as a particular type of arbitration—that depend entirely on the use of mental processes. In other words, the patent statute does not allow patents on particular systems that depend for their operation on human intelligence alone, a field of endeavor that both the framers and Congress intended to be beyond the reach of patentable subject matter. Thus, it is established that the application of human intelligence to the solution of practical problems is not in and of itself patentable". However "When an unpatentable mental process is combined with a machine, the combination may produce patentable subject matter, as the Supreme Court’s decision in Diehr and our own decisions in State Street Bank and AT&T have confirmed." But "The routine addition of modern electronics to an otherwise unpatentable invention typically creates a prima facie case of obviousness".