United States: The Importance Of Unpredictability In Claimed Ranges

Holding

In parallel inter partes review proceedings, petitioner Scientific Design Company, Inc. ("Scientific Design") challenged the patentability of all claims of U.S. Patent Nos. 8,357,825 ("the '825 patent") and 8,357,813 ("the '813 patent") owned by Shell USA, Inc. ("Shell"). The Patent Trial and Appeal Board ("PTAB" or "Board") determined that Scientific Design established by a preponderance of the evidence that claims 1–28 of both patents were obvious.¹ Notably, both patents were found obvious over the same combinations of references and via the same rationale; as well, the parties made the same arguments in both proceedings. For simplicity, this blog post will cite solely to IPR2022-00158 when analyzing points made in both proceedings.

The '825 and '813 patents are directed to processes for epoxidation of olefins and disclose an improved catalyst to accomplish the process. Additionally, the '813 patent pertains to preparation of a 1,2-diol, a 1,2-diol ether, or an alkanolamine using an olefin oxide prepared using the epoxidation process.

Representative claims are set forth below with the shared language underlined.

In both proceedings, the Board determined that "no claim terms require[d] express construction." IPR2022-00158, Paper 37 at *8.

Claims 1–14 and 17–28 of each patent were obvious over Lockemeyer in view of Liu.

Scientific Design alleged that claims 1–14 and 17–28 of the '813 and '825 patents were obvious over Lockemeyer in view of Liu. In line with the Board's opinions, this post focuses on arguments made regarding claim 1 of each patent.

Scientific Design alleged that all limitations of claim 1 of the '813 and '825 patents were expressly disclosed by Lockemeyer, except for the limitation requiring that the catalyst carrier have "at least 80% of the pore volume contained in the pores with diameters in the range of from 0.1 to 10 µm is contained in pores with diameters in the range of from 0.3 to 10 µm." Id. at *14.

Scientific Design and Shell primarily disputed (1) whether a person of ordinary skill in the art ("POSA") would be motivated to use the carriers disclosed in Liu to optimize the particle size distribution disclosed in Lockemeyer, and (2) whether doing so would be routine activity.

Scientific Design asserted that, although "Lockemeyer does not disclose a breakdown in the range of pores with diameters of 0.3–10 µm," it "discloses a pore size distribution in the range of 0.2–10 µm," and a POSA "would have been motivated to modify the pore size distribution of carriers to optimize performance, as a matter of routine." Id. Scientific Design likewise asserted that a POSA would have been motivated to optimize the pore size distribution of Carriers S, T, and/or V of Liu, which all had a pore size distribution within the ranges taught by Lockemeyer. Id. Moreover, because Liu teaches a catalyst's carrier impacts its performance and Lockemeyer teaches that "pore size distribution with pore size within a defined range plays 'a significant role,'" Scientific Design asserted that a POSA would have been motivated to use Liu to optimize the pore size distribution within the ranges disclosed by Lockemeyer. Id. at *14–15.

In response, Shell argued that Scientific Design failed to adequately establish a "non-hindsight reason" why a POSA would be motivated to use Liu to optimize the pore size distribution of Lockemeyer. Id. at *18. Shell pointed out that, as compared to Lockemeyer's carriers, certain of Liu's carriers had a higher percentage of pores greater than 10 µm; included different amounts of silver and different promoters; and were tested using different reaction processes. Id. at *18–19. Shell also argued that Scientific Design failed to establish that routine optimization would have led a POSA to the claimed pore size distribution because "there was nothing 'routine' about 'abandoning use of a single-range [pore size distribution] in favor of two nested ranges." Id. at *19. Lastly, Shell argued that overlapping range caselaw should not apply because Lockemeyer did not expressly disclose the 0.3–10 µm nested range, and that because the claims recite "interdependent variables" a different line of caselaw controls in determining obviousness. Id. at *20.

The Board agreed with Scientific Design, finding that Lockemeyer "already discloses a [pore size distribution] 'such that the pores with diameters from 0.2–10 µm represent more than 75%, in particular more than 80% of total pore volume" and that a POSA would be motivated to optimize the pore size distribution to disclose the nested range of claim 1 in view of the teachings in Liu. Id. at *22. A POSA would find this motivation through Lockemeyer's teaching that pore size distribution "'play[s] a significant role' in preparing carriers for catalysts with excellent properties" and Liu's examples disclosing carriers S, T, and V which were described as enhancing the selectivity, activity, and stability of catalysts. Id. at *22. The Board also found credible Scientific Design's expert's testimony regarding a POSA's expectation of success in completing this optimization. The Board found Shell's purported distinctions between the carrier systems of Lockemeyer/Liu and the '825 and '813 patents unpersuasive.

Moreover, the Board agreed with Scientific Design that a POSA "would have been motivated to modify the pore size distribution of [Lockemeyer's] carriers to optimize performance, as a matter of routine" and thus arrive at the claimed carriers in light of Lockemeyer's express invitation for a POSA to do so. Id. at *25 (emphasis in original).

Further, the Board disagreed with Shell's assertions that its claims recited "interdependent variables" and merited consideration under ModernaTX v. Arbutus Biophama Corp., 18 F.4th 1364, 1376 (Fed. Cir. 2021) because "that case did not involve an overlapping range between the claimed composition and prior art, and the evidence there showed that the claimed variables interacted in an unpredictable way." Id. at *26. By contrast, Shell provided no persuasive evidence to demonstrate that the claimed variables interact in an unpredictable way. Id. Indeed, concerns about unpredictability were mitigated in the Board's view because (1) "the asserted references are directed to essentially the same chemical reaction using essentially the same chemical reagents" and (2) Lockemeyer disclosed all limitations of the asserted claims except the nested pore size distribution within claim 1 along with an invitation to further refine its disclosed carriers. Id. at *26–27. Lastly, the Bord found Shell's assertions that Scientific Design failed to demonstrate obviousness of the claims "as a whole" to be unconvincing and conclusory in view of the Scientific Design's evidence regarding motivation to combine. Id. at *28

Claims 15 and 16 of each patent were obvious over Lockemeyer in View of Liu, Lockemeyer-II, and Kowaleski.

The Board found claims 15 and 16 of the '813 and '825 patents obvious over of Lockemeyer in view of Liu, Lockemeyer-II, and Kowaleski.

Regarding claim 15, Scientific Design argued that a POSA would have been motivated to combine the teachings of Lockemeyer and Liu—which disclose that bond materials may comprise alkali metal silicates—with those of Lockemeyer-II and Kowaleski because "all [four] references disclose high purity alpha-alumina carriers for silver-containing catalysts for making [ethylene oxide]." Id. at *30. Thus, a POSA would have a reasonable expectation of success in using calcium or magnesium silicate as a bond material in Lockemeyer's carriers. Id.

Regarding claim 16, which required the bond material to further comprise "one or more additional component selected from the group consisting of a hydrated alumina, a zirconium component and a titanium component," Scientific Design argued that Lockemeyer and Liu disclosed a carrier comprising hydrated alumina, Lockemeyer-II disclosed titanium or hydrated alumina, and Kowaleski taught zirconium or titanium. Id. at *30.

Shell did not respond specifically to Scientific Design's arguments for claims 15 and 16, and instead argued that the alleged deficiencies in Scientific Design's arguments regarding Lockemeyer and Liu carried over.

The Board sided with Petitioner, finding that Scientific Design established by a preponderance of the evidence that a POSA would have been motivated to combine the four references in the manner claimed and had a reasonable expectation of success in so doing. Id. at *31–32.

Other Grounds Not Addressed

Because the Board found every challenged claim of both patents obvious over Lockenmeyer in view of Liu, and Lockenmeyer in view of Liu, Kowaleski, and Lockenmeyer-II, it did not address the merits of Scientific Design's other unpatentability grounds. IPR2022-00158 at *32; IPR2022-00159 at *33–34.

Takeaways and Considerations for Practitioners:

• When alleging that overlapping range law does not apply in determining obviousness of claims, practitioners representing patent owners should demonstrate why claimed ranges are unpredictable and/or establish criticality of the claimed range to rebut a determination of obviousness.
• Likewise, practitioners representing patent owners should endeavor to argue deficiencies for each asserted unpatentability ground, rather than simply stating that deficiencies from other grounds carry over.

Footnote

1. Scientific Design Company, Inc. v. Shell USA, Inc., IPR2022-00158, Paper 37 (Mar. 28, 2023); Scientific Design Company, Inc. v. Shell USA, Inc., IPR2022-00159, Paper 37 (Mar. 28, 2023).

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.