James Watt and his patents on steam engine are also an interesting case. Efficiency gains basically stopped for duration of the main patent patent and exploded

James Watt and his patents on steam engine are also an interesting case. Efficiency gains basically stopped for duration of the main patent patent and exploded later. On the other hand it is also case for more innovation due to necessity, e.g. his patent on beam connection to a shaft (linear-to-rotary movement) required others to come up with a different solutions (e.g. sun and planet gear).