http://www.paulgraham.com/softwarepatents.html
by PaulGraham
"Patent trolls seem to have caught big companies by surprise. In recent years, they've extracted hundreds of millions of dollars from them. Patent trolls are hard to fight precisely because they create nothing. Big companies are safe from being sued by other big companies because they can threaten a counter-suit. But because patent trolls don't make anything, there's nothing they can be sued for. I predict this loophole will get closed fairly quickly, at least by legal standards. It's clearly an abuse of the system, and the victims are powerful." (emphasis by me)
It seems he predicted correctly:
http://www.forbes.com/2006/05/15/ebay-scotus-patent-ruling-cx_jh_0516scotus_print.html (discussed in http://yro.slashdot.org/article.pl?sid=06/05/16/135257).