Patents don't kill innovation but they do next to nothing to promote it.
Only a very small percentage of patents are ever successfully licensed to anyone. Around 3% recoup the cost of filing the patent. Half of all patents expire prematurely when the owner declines to pay the required maintenance fees.
That 97% of the patents don't go recoup the cost is a statistic known to companies and patent lawyers. This should only serve to make them more careful about filing patents. In other words, inventions less likely to be effective would be passed upon by them themselves.
Only a very small percentage of patents are ever successfully licensed to anyone. Around 3% recoup the cost of filing the patent. Half of all patents expire prematurely when the owner declines to pay the required maintenance fees.