Are More Important Patents Approved More Slowly and Should They Be?

Innovative activities often are heavily regulated. Reviews conducted by administrative agencies take time and are not perfectly accurate. Of particular concern is whether, by design or not, such agencies discriminate against more important innovations by taking more time to perform their reviews. We study the relationship between the length of patent review and the importance of inventions in a theoretical model. We find that, controlling for the importance of innovations, the welfare-maximising patent approval delay decreases over time. Second, controlling for a patent's position in the new technology cycle, the optimal examination time decreases with the importance of patents. We test our predictions on US GM crop patent data from 1988 to 1998. The evidence supports the predictions of the theoretical model.