Using a vertical differentiation model of endogenous growth with stochastic R&D activity, we characterise the optimal patent lifetime a government would set in order to maximise economic growth. We show that a finite patent lifetime does exist and is unique provided that the expected rate of...

We consider an endogenous growth model with two sectors: an intermediate input (or "upstream") sector and a final product (or "downstream") sector. Innovation takes place in both sectors. Following Gilbert and Shapiro (1990), we define patent breadth as the ability of the innovator to reap...

We analyze recent contributions to growth theory based on the model of expanding variety of Romer [Romer, P. (1990). “Endogenous technological change”. Journal of Political Economy 98, 71–102]. In the first part, we present different versions of the benchmark linear model with imperfect...

An endogenous growth model is developed where each period firms invest in researching and developing new ideas. An idea increases a firm's productivity. By how much depends on how central the idea is to a firm's activity. Ideas can be bought and sold on a market for patents. A firm can sell an...

Using a vertical differentiation model of endogenous growth with stochastic R&D activity, we characterise the optimal patent lifetime a government would set in order to maximise economic growth. We show that a finite patent lifetime does exist and is unique provided that the expected rate of...

Modeling the spatial aspect of growth has finally become an important subject of economics as exemplified by the increasing popularity of the new economic geography. However, new economic geography models have still not been able to develop a consistent approach to integrate innovation, space...

The novelty requirement seeks to ensure that a patent will not issue if the public already possesses the invention. Although gauging possession is usually straightforward for simple inventions, it can be difficult for those in complex fields like biotechnology, chemistry, and pharmaceuticals....

At the regional scale, human capital and agglomeration forces are assumed to shape innovative capacity, but there are likely to be more direct channels like the development and commercialization of new products. This article examines the relationship between inventive activity and productivity...

A bedrock principle of patent law is that old inventions cannot be patented. And a new use for an old invention does not render the old invention patentable. This is because patent law requires novelty—an invention must be new. But while a new use for an old invention does not make the old...

Due to the cumulative nature of innovation, access to knowledge is important. Although evidence exists concerning the positive impact of increased knowledge access on the rate of inventive activity, less is known about its influence on the direction of inventive activity. I examine how a change...