Patents are supposed to spread knowledge by making those filing for a patent describe the innovation in detail. But patent lawyers are masters of obfuscation, and try to make claims that cover every permutation they can think of, whether they've tried it or not. Their competitors then try to find a way around the patent to avoid paying royalties. It could be argued that patents actually slow down innovation, especially when ideas can be copied much more easily in the information age than in the 1700s when the current patent system began.