Via Bruce Hobbs, on LeftLibertarian
. Michele Boldrin and David K. Levine. Against Intellectual Monopoly
. Here's a great quote from the opening of Chapter One:
Once Watt’s patents were secured, a substantial portion of his energy was devoted to fending off rival inventors. In 1782, Watt secured an additional patent, made “necessary in consequence of ... having been so unfairly anticipated, by [Matthew] Wasborough in the crank motion.” More dramatically, in the 1790s, when the superior and independently designed Hornblower engine was put into production, Boulton and Watt went after him with the full force of the legal system. In contrast to Watt, who died a rich man, the inventor Jonathan Hornblower was not only forced to close shop, but found himself ruined and in jail.
...The fuel efficiency of steam engines is not thought to have changed at all during the period of Watt’s patent; while between 1810 and 1835 it is estimated to have increased by a factor of five. After the expiration of Watt’s patents in 1800, not only was there an explosion in the production of engines, but steam power finally came into its own as the driving force of the industrial revolution. In the next 30 years steam engines were modified and improved, and such crucial innovations as the steam train, the steamboat and the steam jenny all came into wide usage. The key innovation was the high-pressure steam engine – development of which had been blocked by Watt by strategically using his 1775 patent.