There are two competing accounts for explaining Britain's technological transformation during the Industrial Revolution. One sees it as the inevitable outcome of a largely exogenous increase in the supply of new ideas and ways of thinking. The other sees it as a demand side response to economic incentives—that in Britain, it paid to invent the technology of the Industrial Revolution. However, this second interpretation relies on the assumption that inventors were sufficiently responsive to new commercial opportunities. This paper tests this assumption, using a new dataset of Scottish and Irish patents. It finds that the propensity of inventors to extend patent protection into Scotland and/or Ireland was indeed closely correlated with the relative market opportunity of the patented invention.