despite the fact that such patents have been granted for some time in the US, it is far from certain that they have been what Sellars and Yeatman would have called a "Good Thing." …Innovation in computer programs, for instance, proceeded at an immense speed for years before anyone thought of granting patents for them as such. There is evidence, in the shape of the mass of US litigation about the excluded categories, that they have produced much uncertainty. If the encouragement of patenting and of patent litigation as industries in themselves were a purpose of the patent system, then the case for construing the categories narrowly (and indeed for removing them) is made out. But not otherwise.’ (Jacob LJ in Aerotel Ltd. Telco Holdings Ltd. [2006] EWCA Civ 137) Comment.