Patents are supposed to spread knowledge, by obliging holders to lay out their innovation for all to see; they often fail, because patent-lawyers are masters of obfuscation. Instead, the system has created a parasitic ecology of trolls and defensive patent-holders, who aim to block innovation, or at least to stand in its way unless they can grab a share of the spoils. An early study found that newcomers to the semiconductor business had to buy licences from incumbents for as much as $200m. Patents should spur bursts of innovation; instead, they are used to lock in incumbents’ advantages.
The patent system is expensive. A decade-old study reckons that in 2005, without the temporary monopoly patents bestow, America might have saved three-quarters of its $210 billion bill for prescription drugs. The expense would be worth it if patents brought innovation and prosperity. They don’t.