We develop a microeconomic model of endogenous growth where clean and dirty technologies compete in production and innovation--in the sense that research can be directed to either clean or dirty technologies. If dirty technologies are more advanced to start with, the potential transition to...

An inventor's own knowledge is a key input in the innovation process. This knowledge can be built by interacting with and learning from others. This paper uses a new large-scale panel dataset on European inventors matched to their employers and patents. We document key empirical facts on...