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...

We build a model of firm-level innovation, productivity growth and reallocation featuring endogenous entry and exit. A new and central economic force is the selection between high- and low-type firms, which differ in terms of their innovative capacity. We estimate the parameters of the model...

What form of intellectual property rights (IPR) policy contributes to economic growth? Should technological followers be able to license the products of technological leaders? Should a company with a large technological lead receive the same IPR protection as a company with a more limited lead?...