With over 1000 IPRs and CBMs already filed and PGR eligible patents beginning to issue, can we expect similar growth of PGR filings? The European Patent Office (EPO) Opposition may provide us a bit of a crystal ball regarding what we can expect from PGR. As previously reported in the AIA blog, there are a number of significant differences such as cost, effect on later litigation and anonymity. However, can these really be seen as substantive differences that would lead to different results and trends than we currently see at the EPO. Both procedures assess anticipation (novelty) and obviousness (inventive step). Both procedures take into account formal matters (written description in the United States, added matter in the EPO) and do not allow broadening of patents. Whilst clarity is not a ground of opposition at the EPO, when amended claims are filed during the opposition process they have to satisfy clarity requirements.

Overall, about 5.5% of European patents granted by the EPO are opposed. Of those, about 1/3 are revoked, 1/3 are maintained in amended form and 1/3 are maintained as granted. Most revocations occur in the area of medical or veterinary science (IPC class G21). The greatest proportion of successful oppositions (i.e. over 60% of patents opposed are revoked) is found in nuclear physics and nuclear engineering (IPC class G21). This is compared with a 6% success rate with storing or distributing gases or liquids (IPC class F17).

The statistics on revocation at the EPO also make interesting reading with 43% of patents revoked in 2010 and 2011 being for lack of inventive step, 22% for lack of novelty, 11% for added matter and 5% for insufficiency.

It does not appear there would be too many differences between the findings in a PGR and an EPO opposition for anticipation and novelty grounds. However, the clear advantage of PGR over IPR is challenging written description and enablement, which account for over 15% of the basis of revocation at the EPO. In the area of added matter (U.S. written description), the EPO has become increasingly strict in recent years as demonstrated by the sizeable 11% of revocations being for just this ground. Will we see a similar trend evolve at the PTAB?

Of course the best barometer for comparing the two procedures will be results from corresponding PGR's and EPO oppositions for the same patent families and claims. As time passes and the PGR decisions roll in it will be interesting to see where there are trends and differences in the outcomes between the two procedures.

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