In the policy debate, intellectual property is often justified by what seems to be a straightforward argument: if innovators are not protected against others appropriating their ideas, incentives for innovation are suboptimally low. Now in most industries for most potential users, appropriating...

An innovative firm chooses strategically whether to patent its process innovation or rely on secrecy. By doing so, the firm manages its rival’s beliefs about the size of the innovation, and affects the incentives in the product market. Different measures of competitive pressure in the product...