Prospects for Improving US Patent Quality via Postgrant Opposition

The recent surge in US patenting and the expansion of patentable subject matter has increased patent office backlogs and raised concerns that, in some cases, patents of insufficient quality or with inadequate search of prior art are being issued. At the same time, patent litigation and its costs are rising. This paper explores the potential of a postgrant review process modeled on the European opposition system to improve patent quality, reveal overlooked prior art, and reduce subsequent litigation. We argue that the welfare gains to such a system may be substantial.