Leveraging Written Description Vulnerabilities in IPR

Bio/pharma patents are rarely targeted in IPR proceedings because their technical vulnerabilities often relate to written description and/or enablement. IPR, of course, is restricted in scope to only grounds of unpatentability that are based on patents and printed publications. And claims in the unpredictable arts, even when challenged in IPR, can be relatively tougher to invalidate as compared to patents in the predictable arts.

That is not to say that 112 issues cannot be litigated in an IPR—only that 112 cannot be a stand-alone trial ground. For example, where a subject patent claims priority to one or more prior filings, the 112 support of those filings is properly litigated in IPR if the claims of the subject patent are argued as lacking support in the earlier filings. The distinction is that 112 is not being assessed as a stand-alone challenge, but rather, as part of the priority assessment to determine the applicability of intervening prior art under 102/103.

The above IPR strategy is not new. However, it might be significantly more valuable to Bio/Pharma patent challengers as a mechanism to force an Amgen analysis on older patent portfolios via IPR.

Taking a step back, while PGR is available for stand-alone 112 challenges (at least for post-2012 patent filings), the the limited PGR window (9 months from issuance) is typically long since closed by the time most high-value Bio/Pharma patents are litigated. Likewise given its expansive scope, even when available, PGR brings added estoppel liability for patent challengers. For these reasons IPR provides the optimum path to 112 review, and why it is the focus here.

As a reminder the SCOTUS in Amgen warned that “the more one claims, the more one must enable” Amgen Inc. v. Sanofi, 143 S. Ct. 1243, 1254, 1257 (2023). The Court also made clear that providing “research assignments” to the public to identify claimed species of a genus in trial and error fashion was improper. Given the claim drafting practices analyzed in Amgen were routine practice, there is a significant inventory of Bio/Pharma patents with this same potential infirmity.

As explained above, to seek IPR for purposes of litigating 112 it is not enough to just point out that the claims are not supported. Intervening art must be identified.

There are a few intervening art scenarios that patent challengers might leverage to secure an Amgen analysis at the PTAB:

  • Apply intervening art in an IPR that potentially invalidates the claims under 102/103;
  • Apply intervening art of the inventors in an IPR that shows further development of the claimed subject matter post-filing to prove them initially unsupported and to invalidate the claims under 102/103;
  • Apply the earliest priority document as intervening art that demonstrates obviousness with its “research assignment” and simultaneously demonstrates that the inventor was not in possession of the invention for 112 purposes.

I expect a renewed interest in intervening art challenges at the PTAB as a mechanism for Bio/Pharma patent challengers to secure an Amgen analysis for undermining a portfolio of related patents.