Decision: ModernaTX, Inc. v. Curevac AG, IPR2017-02194, Paper 45 (P.T.A.B. April 16, 2019) (SAWERT, Moore, Mitchell)

Holding: The PTAB determined that Petitioner showed by a preponderance of the evidence that claims 1-26 of U.S. 8,383,340 would have been unpatentable as obvious.

Background: Initially the PTAB instituted trial on the asserted obviousness grounds but denied the anticipation ground. After SAS, the PTAB modified its institution decision to include the anticipation ground.

Claim 1 is the only independent claim and reads:

1. A method for purifying RNA on a preparative scale, wherein the RNA is purified by HPLC or low or normal pressure liquid chromatography using a porous reversed phase as stationary phase and a mobile phase, wherein the porous reversed phase is a porous non-alkylated polystyrenedivinylbenzene.

The PTAB began its analysis by construing the claim. The parties disputed whether the preamble was limiting, with the Petitioner arguing it was not and the Patent Owner arguing that it was. An interesting point is that in claim 1, there is no traditional transition language, such as "comprising," "consisting essentially of," or "consisting of." The PTAB found the preamble limiting, concluding that the preamble was "for purifying RNA on a preparative scale." The PTAB found that preamble was "not merely a statement of purpose," "'but rather discloses a fundamental characteristic of the claimed invention that is properly construed as a limitation of the claim itself.'"

The PTAB found support for this conclusion in the specification, which "repeatedly characterizes a fundamental characteristic of the claimed invention as purifying RNA on a preparative, versus an analytical, scale." The PTAB interpreted "on a preparative scale" in the preamble as "at least 100 μg RNA." The preamble also provided an antecedent for the recitation of "the RNA" in the body of the claim. But the PTAB rejected Patent Owner's attempt to add "and collecting for downstream use" to the preamble. There was no language in the written description of the patent that supported that addition.

The PTAB next proceeded to construe "'porous reversed phase' as a nonpolar stationary phase characterized by pores in which the RNA molecules can enter and be retained during the chromatography process." This construction was supported by the specification and extrinsic evidence ("the '340 patent uses 'porous' (and 'nonporous') in a manner consistent with the art of record."). Focusing strongly on the '340 patent, the PTAB rejected the argument of the Petitioner that the '340 patent specification's use of the words "may" and "possibility" compelled a conclusion different from that of PTAB. The '340 patent specification "when read and understood in its entirety" supported PTAB's conclusion.  

The Petitioner put up an expert to support its argument of claim construction.  The PTAB, however, criticized the Petitioner's expert's testimony for focusing on isolated words, being conclusory, unsupported, and inconsistent with the prior art (including the Petitioner's own exhibits), and contradicting the expert's own previously published work. The PTAB focused on the expert's argument that the '340 patent does not require a particular pore size for a particular RNA size. The PTAB found the expert's testimony not credible in light of the evidence of record.

With respect to a range recited in a dependent claim, "wherein the RNA has a size of up to 100 to 10000 nucleotides or base pairs," the PTAB agreed with the Petitioner that "up to" means that there is no lower limit on the claim. Replacing 'of up to' with 'of,' as Patent Owner suggested, improperly reads 'up to' out of the claim."

Having construed the claim terms, the PTAB provided an overview of the references before turning to the Petitioner's arguments.  For anticipation, the Petitioner argued that the preamble was not limiting. The PTAB rejected that argument. Because the "preparative scale" language of the preamble was construed by the PTAB as limiting, the asserted reference failed since it did "not disclose preparative HPLC." The PTAB faulted the Petitioner for not providing an alternative argument in case the preamble was found limiting:

Petitioner premises its ground of unpatentability for anticipation on its view that the preamble is not limiting, and makes no separate argument in the Petition that the claims are also unpatentable for anticipation by Gjerde I even if the preamble is limiting. .... For example, in its claim chart, Petitioner fails to map the language of the preamble to any teachings in Gjerde I. ... Dr. Hornby also testifies that he "was asked to assume that the preamble of claim 1 is not limiting," and, for that reason, states that "Gjerde I does not have to disclose purification on a preparative scale." ...Because we determine that the preamble is limiting, supra § III.C.2., Gjerde I must teach preparative-scale purification to anticipate.  In re Paulsen, 30 F.3d 1475, 1479 (Fed. Cir. 1994).  Petitioner makes no such argument, and thus fails to demonstrate by a preponderance of the evidence that claims 1–5, 8, 10–22, and 26 are unpatentable as anticipated by Gjerde I.  

Id. at *34.

The Petitioner's obviousness argument, however, was successful; the prior art sufficiently disclosed or suggested each element of the challenged claims, as construed. The PTAB rejected the Patent Owner's characterization of the prior art as too narrow, citing Beckson Marine, Inc. v. NFM, Inc., 292 F.3d 718, 727 (Fed. Cir. 2002) ("[O]bviousness does not require the prior art to reach expressly each limitation exactly.  Rather, obviousness may render a claimed invention invalid where the record contains a suggestion or motivation to modify the prior art teaching to obtain the claimed invention.") The PTAB also cited Hoffmann-La Roche Inc. v. Apotex Inc., 748 F.3d 1326, 1331 (Fed. Cir. 2014) ("Conclusive proof of efficacy is not necessary to show obviousness."). The Patent Owner's argument was also rejected because it relied on its unreasonable construction of the claimed range, discussed above.

The PTAB found that there was a sufficient motivation to combine the teachings of the prior art and a reasonable expectation of success, noting that this case fit within KSR's "finite number of identified, predictable solutions" within the skill of a POSITA. "[T]he record supports, by a preponderance of the evidence, Petitioner's explanation that, before the '340 patent's earliest effective filing date, there was a known need in the art for skilled artisans to produce large quantities of purified RNA for antisense therapy." The asserted reference Lloyd "suggests a finite number of high-performance PSDVB-based columns, PLRP-S and PL-SAX, and further that Lloyd suggests ion-pair reversed-phase chromatography as 'an obvious choice' for obtaining preparative amounts of high-purity oligonucleotides. Thus, we agree with Petitioner that an ordinarily skilled artisan 'would have had reason to select Lloyd's method to purify Zhang's antisense RNA.'"

The PTAB rejected some of the Patent Owner's arguments against a reasonable expectation of success because some citations relied upon could not be found in the exhibit provided (e.g., cited pages 82-83 and 87 of an exhibit that ended at page 66; see FN 17) and rejected others because they applied too strict of a standard for success. "[T]he test for obviousness does not require 'actual success' in the prior art.... '[O]nly a reasonable expectation of success, not a guarantee, is needed.'"

The PTAB also rejected Patent Owner's argument against "obvious to try," finding instead that this case falls within the Supreme Court's permissible use of "obvious to try":

The Federal Circuit has since identified two instances where an obvious-to-try theory must fail: (1) when "what would have been 'obvious to try' would have been to vary all parameters or try each of numerous possible choices until one possibly arrived at a successful result, where the prior art gave either no indication of which parameters were critical or no direction as to which of many possible choices is likely to be successful"; and (2) when "what was 'obvious to try' was to explore a new technology or general approach that seemed to be a promising field of experimentation, where the prior art gave only general guidance as to the particular form of the claimed invention or how to achieve it." In re Kubin, 561 F.3d 1351, 1359 (Fed. Cir. 2009) (quoting In re O'Farrell, 853 F.2d 894, 903 (Fed. Cir. 1988)).

Id. at *71.

According to the PTAB, "this is not a case where the prior art gave no direction or the skilled artisan was faced with numerous possible choices...[or] the skilled artisan had to set out on a new path with little guidance from the prior art."

The Patent Owner's objective evidence of unexpected results was rejected for lack of nexus (the Patent Owner did not allege a nexus) and because the Patent Owner did not compare the allegedly unexpected results to the closest prior art.

PTAB Practice Takeaways:

Every case depends on its own facts and circumstances. In this case, the PTAB found flaws in both parties' expert testimony and analysis of applicable cases. Conclusory testimony was given little weight, and the PTAB found that certain testimony was inconsistent with facts in the record. The PTAB also found that certain arguments of both parties failed to address critical aspects of the applicable case law. This case may suggest to the practitioner, whether representing a petitioner or a patent owner, to ferret out, depending on the facts and circumstances, unfavorable facts and law and consider the pros and cons of proactively addressing such issues.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.