obviousness.
when applying for a patent. it must pass the obvious rule. in other words to a person skilled in the art is this patent application 'obvious'. The defense of that has always been. well if it was so obvious why didnt you patent it.
The response that is its obvious, which is why you are suing me and because its obvious I did not consider it patentable.
It seems to me most software patents fall under the obvious rule. many other patents do as well. I am bamboozled as to how they get past reviews. I don't think the patent system is so much broken as the review system. if patents were routinely denied as obvious. then much of this litigation would go away.
The patent offices around the world are responsible for this mess.
And for some good new new zealand has said no to software patents.
http://au.ibtimes.com/articles/502780/20130901/new-zealand-parliament-bans-software-patent-information.htm