The text is from a talk in Cambride in 2002. It is a nice read.
RMS comments on a BT patent on using hyperlinks when connected to the net: "It is rather like having a patent on a sofa and television in the same room."
I saw Tim Bray wrote about his view on patents, saying "...it's almost impossible for rational people to have a rational discussion about software patents. The reason is the insanely-dysfunctional behavior of the US Patent and Trademark Office, whose idiotic willingness to grant patents on anything without regard for prior art or the obviousness test has totally poisoned the waters of this discussion". I agree rational discussion is difficult, but hardly because of the strange behaviour of the USPTO. Would all be ok, really, if we just didn't have those much talked about patents? I'm sure it would not change. It is about so much more than inadequate patents. Even the correct software patents are disturbing and upsetting to the "victims" (developers).
My view is that the strong holds in this matter are because of the severe restrictions that come with software patents. Since the patents are about ideas, they, sort of, limit your freedom - you can still think freely, as long as you don't write your thoughts in code. I think RMS' talk explains this quite well.