In a Final Written Decision (FWD) in a post-grant review (PGR), the Patent Trial and Appeal Board (PTAB) addressed post-grant review eligibility, enablement, written description and anticipation.  US Endodontics, LLC v. Gold Standard Instruments, LLC, Case No. PGR2015-00019 (PTAB, Dec. 28, 2016) (Goodson, APJ). 

Only patents that are subject to the American Invents Act (AIA) first-inventor-to-file provisions, i.e., maturing from an application that contains a claim having an effective filing date on or after March 16, 2013, are eligible for PGRs.  Petitioners bear the burden of demonstrating that a patent is eligible and the challenged patent here claims priority to a series of continuations and divisionals dating back to June 7, 2005, as well as to a provisional application filed on June 8, 2004.

Petitioner argued that several of the challenged claims were not entitled to a filing date earlier than the actual filing date of the application that matured into the challenged patent, which was later than March 16, 2013.  Petitioner argued that the challenged patent did not satisfy either the enablement or written description requirements for the challenged claims, notwithstanding that it shares the same specification as the priority applications.  Thus, petitioner argued the claims were not entitled to claim priority to the earlier applications, and were therefore eligible for PGR.  PTAB agreed.

As to enablement, Petitioner’s arguments focused on the disclosed range of temperatures at which the claimed heat treatment of the claimed endodontic instruments occurs.  Petitioner argued the method is inoperative because heat testing results did not exhibit the claimed permanent deformation that should have resulted from using the claimed heat treatment parameters.  PTAB agreed, finding that “the guidance the Specification provides regarding how to achieve the deformation characteristic recited in the ‘wherein’ clause is quite limited compared to the broad scope of [the] claims … .”  Further, “the inclusion in a claim’s scope of inoperative species is a relevant consideration in the enablement analysis” and “the inability to achieve what is recited in the ‘wherein’ clause using heat-treatments within the scope of the claims contributes to the enablement problem.”  PTAB also agreed that an artisan would require undue experimentation to practice the full scope of the challenged claims using the teachings of the specification as a guide.

As to written description, the Petitioner, citing the en banc Federal Circuit decision in Ariad (2010), argued that the challenged claims  do not satisfy the § 112 written description requirement.  The written description analysis looks at whether application reasonably conveys to those skilled in the art that the inventor had possession of the claimed subject matter as of the filing date.  Petitioner argued that under Ariad, use of functional language (i.e., the “wherein” clause) to define the boundaries of the claimed genus (i.e., to claim the desired permanent deformation result) was insufficient because the functional language simply claims a desired result without describing how to achieve that result.  PTAB agreed concluding that the specification did not demonstrate possession of heat-treatment in the claimed range in order to achieve the claimed result.

PTAB also agreed with Petitioner that the challenged claims were anticipated by a 2008 published patent application.  The patent owner’s only argument was that the published application post-dates the claimed priority date.  However, due to its earlier determination regarding the effective filing date of the challenged claims, PTAB concluded the published application was prior art and anticipatory.