An Emerging PTAB Threat For Bio/Pharma: Leveraging Written Description Vulnerabilities In IPR

Bio/pharma patents are rarely targeted in inter partes review (IPR) proceedings because their technical vulnerabilities often relate to written description and/or enablement. IPR, of course, is restricted in scope to grounds of unpatentability that are based on patents and printed publications. Claims in the unpredictable arts, even when challenged in IPR, can be relatively tougher to invalidate as compared to patents in the predictable arts. Section 112 (written description) issues can be litigated in an IPR—but Section 112 cannot provide the stand-alone trial ground.

For example, where a subject patent claims priority to one or more prior filings, the Section 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 Section 112 is not being assessed as a stand-alone challenge, but rather, as part of the priority assessment to determine the