Can Post-Grant Reviews Improve Patent System Design? A Twin Study of US and European Patents

This paper assesses the impact of adopting a post-grant
review institution in the US patent system by comparing the opposition careers of European Patent Office (EPO) equivalents of litigated US patents to those of a control group of EPO patents. Our results provide strong evidence that the United States could benefit substantially from adopting an administrative post-grant patent review, provided that the post-grant mechanism is not too costly.