A recently-published study suggests that the quality of patent examination undertaken in the United States Patent and Trademark Office (USPTO) is higher than that undertaken by the European Patent Office (EPO) and the Australian Patent Office (APO).

The study, published in 16 J. Marshall Rev. Intell.  Prop. L. (2016), provides an answer to a question that, rather surprisingly, has not been addressed in the academic literature to date:  What is the practical effect of patent examination?  It does so by undertaking an empirical analysis of the examination of nearly 500 patent applications, filed in identical form, in the USPTO, the EPO and the APO.

Analysis of the data shows that the routine effect of patent examination is to produce meaningful change to – and, in particular, a narrowing of – the definition of the invention contained in claim 1 of the patent.  Importantly, this effect occurs significantly more often in the USPTO than in the EPO, and significantly more often in both of those offices than in the APO.

Surprisingly, given the commonly-expressed view that the USPTO issues many “bad” patents, these findings suggest that the quality of patents granted by the USPTO may be higher than those granted by the other two offices.