Pricing is hard and getting the right time-period for a monopoly on an idea is no different.

And then the Patent Office profits by awarding patents putting the negative externality burden on those in the field of the patent to "fix" mistakes.

For a man of his historical importance Jefferson had a lot of questionable ideas (owning slaves, blaming banks for his debt, monopolies on ideas, and I don't care much for the speeches I've read of his either).

Louisiana Purchase turned out all right though.