Misclassification between Patent Offices: Evidence from a Matched Sample of Patent Applications

In this paper, we estimate the extent of misclassification in patent examination decisions between the European Patent Office (EPO) and the Japanese Patent Office (JPO), that is, applications that are incorrectly refused a patent or incorrectly granted a patent. Using a proxy for inventive step as the predictor of the correct decision, we find that the probability that a “true grant” application is refused is 6.1%, while the probability that a “true refusal” application is granted is 9.8%. However, we find no evidence of an increasing trend of granting “bad” patents at the EPO and JPO. © 2011 The President and Fellows of Harvard College and the Massachusetts Institute of Technology.