Big companies are interested in getting rid of patent trolls, because the defense against trolls is asymmetric. They would like a system that allows them to att

Big companies are interested in getting rid of patent trolls, because the defense against trolls is asymmetric. They would like a system that allows them to attack or defend against other large companies, while they remain immune from trolls, such as Intellectual Ventures and its off-springs, like LodSys. One solution would be a 2 year expiration on software patents. Another idea would be to demonstrate "substantial" sales for renewals.