Trials@uspto.gov Paper 34
`571-272-7822 Date: November 4, 2025
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`UNITED STATES PATENT AND TRADEMARK OFFICE
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`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
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`PACIFICORP,
`Petitioner,
`v.
`BIRCHTECH CORP.,
`Patent Owner.
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`IPR2025-00718
`Patent 10,926,218 B2
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`Before KRISTINA M. KALAN, ZHENYU YANG, and
`AVELYN M. ROSS, Administrative Patent Judges.
`
`YANG, Administrative Patent Judge.
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`
`DECISION
`Granting Institution of Inter Partes Review
`35 U.S.C. § 314
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`IPR2025-00718
`Patent 10,926,218 B2
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`I. INTRODUCTION
`PacifiCorp, Interstate Power & Light Company (“IPL”),
`MidAmerican Energy Company (“MidAmerican”), WEC Energy Group,
`Inc. (“WEC”), and Wisconsin Power & Light Company (“WPL”) filed a
`Petition (Paper 1, “Pet.”), seeking inter partes review of claims 1–4
`and 6–26 of U.S. Patent No. 10, 926,218 B2 (Ex. 1001, “the ’218 patent ”).
`IPL, WPL, WEC, and MidAmerican subsequently settled their dispute with
`Birchtech Corp. (“Patent Owner”) ,1 and have been terminated from this
`proceeding. Papers 25, 30, 33. Accordingly, “Petitioner” as used herein
`refers only to the remaining Petitioner, namely, PacifiCorp.
`Patent Owner filed a Preliminary Response. Paper 16 (“Prelim.
`Resp.”).2 With our authorization (Ex. 3001), Petitioner filed a Reply to the
`Preliminary Response (Paper 24, “Reply”), and Patent Owner filed a
`Sur-reply to Petitioner’s Reply (Paper 26, “Sur-reply”).
`We have authority under 35 U.S.C. § 314, which provides that an
`inter partes review may not be instituted “unless . . . there is a reasonable
`likelihood that the petitioner would prevail with respect to at least 1 of the
`claims challenged in the petition.” 35 U.S.C. § 314(a).
`For the reasons provided below, we determine Petitioner has satisfied
`the threshold requirement set forth in 35 U.S.C. § 314(a). We institute inter
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`1 Birchtech Corp. was formerly known as Midwest Energy Emissions Corp.
`(“ME2C”) (Paper 9, 2),
`2 The parties also filed briefs, arguing for and against discretionary denial.
`Papers 15, 17. The Acting Director determined that discretionary denial was
`not appropriate and referred the Petition to the Board. Paper 23.
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`Patent 10,926,218 B2
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`partes review of all challenged claims based on all the grounds raised in the
`Petition.
`A. Real Parties in Interest
`The Petition identifies Berkshire, IPL, MidAmerican, PacifiCorp,
`WEC, and WPL , as well as Alliant Energy Corporation , Alliant Energy
`Corporate Services, Inc. , MidAmerican Funding, LLC, MHC Inc., PPW
`Holdings LLC, Madison Gas and Electric Company, and Wisconsin Public
`Service Corporation as real parties in interest. Pet. 1–2.
`Patent Owner identifies “MES, Inc.” as the real party in interest.
`Paper 9, 2.
`B. Related Matters
`Petitioner filed a concurrent petition (IPR2025-00717), seeking inter
`partes review of the same claims challenged in this proceeding. 3 Pet. 2–3.
`The parties identify the following matters as related to this
`proceeding:
`Midwest Energy Emissions Corp. et al. v. Arthur J. Gallagher
`& Co. et al., No. 1:19-cv-01334 (D. Del.) (“the Delaware
`Action”);
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`3 Petitioner filed an explanation regarding the necessity of multiple petitions.
`Paper 2. Patent Owner does not challenge that multiple petitions are
`necessary. See generally Prelim. Resp. In any event, whether to deny
`institution because a petitioner filed multiple petitions is best raised and
`resolved through the process involving a bifurcated procedure for
`considering discretionary issues. See USPTO Memorandum, Interim Process
`for PTAB Workload Management (March 26, 2025), available at
`https: //uspto.gov/sites/default/files/documents/InterimProcesses-
`PTABWorkloadMgmt-20250326.pdf.
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`IPR2025-00718
`Patent 10,926,218 B2
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`Midwest Energy Emissions Corp. v. Tucson Electric Power Co.
`et al., No. 3:24-cv-08145 (D. Ariz.);
`Midwest Energy Emissions Corp. v. Berkshire Hathaway
`Energy Co. et al. , No. 4:24-cv-00248 (S.D. Iowa);
`Midwest Energy Emissions Corp. v. Ameren Corporation et al.,
`No. 4:24-cv-00980 (E.D. Mo. );
`In re Midwest Energy Emissions Corp. Patent Litigation,
`No. 4:24-md-3132 (S.D. Iowa) (consolidating the Iowa,
`Arizona, and Missouri cases);
`Midwest Energy Emissions Corp. v. Berkshire Hathaway
`Energy Company et al., No. 2:25-cv-00015 (D. Wy.);
`Midwest Energy Emissions Corp. v. Wisconsin Power and Light
`Company, No. 3:25-cv-00026 (W.D. Wis.);
`Midwest Energy Emissions Corp. v. MidAmerican Energy
`Company et al., Case No. 4:24-cv -00243 (S.D. Iowa);
`Birchtech Corp. f/k/a Midwest Energy Emissions Corp. v.
`Evergy, Inc. et al. , Case No. 4:25-cv -00050 (W.D. Mo.);
`Midwest Energy Emissions Corp. v. Evergy. Inc. et al. , Case
`No. 4:25-cv-00046 (S.D. Iowa); and
`Birchtech Corp. f/k/a Midwest Energy Emissions Corp. v.
`Evergy, Inc. et al. , Case No. 5:25-cv-04033 (D. Kan.).
`Pet. 5–6; Paper 9, 2–3.
`Petitioner previously filed other petitions for inter partes review,
`challenging two other patents owned by Patent Owner. Pet. 3 –4. Those
`petitions are: IPR2025-00274 and IPR2025-00278, challenging claims of
`U.S. Patent No. 10,343,114 (“the ’114 patent”); and IPR2025-00280 and
`IPR2025-00281, challeng ing claims of U.S. Patent No. 10,596,517;
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`IPR2025-00718
`Patent 10,926,218 B2
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`IPR2025-00422 and IPR2025-00423, challenging claims of U.S. Patent
`No. 10,668,430; IPR2025-00424 and IPR2025-00425, challenging claims of
`U.S. Patent No. 10,589,225; and IPR2025-00687 and IPR2025-00688,
`challenging claims of U.S. Patent No. 10,933,370. Id. The Board instituted
`trial in those proceedings.
`Petitioner also brings to our attention several inter partes review
`proceedings, with petitions filed by other entities, including IPR2020-00832
`and IPR2020-00834, challenging claims of the ’114 patent ; and
`IPR2020-00926 and IPR2020-00928, challenging claims of a parent patent
`of the ’218 patent. Pet. 4–5. According to Petitioner, the Board granted
`institution but terminated those proceedings because the parties settled. Id.
`C. The ’218 Patent
`The ’218 patent “relates to methods and materials for the removal of
`pollutants from flue gas or product gas from a gasification system. In
`particular, mercury is removed from gas streams generated during the
`burning or gasification of fossil fuels by highly reactive regen erable
`sorbents. ” Ex. 1001, 1:46–50.
`The ’218 patent states that
`[t]he combustion and gasification of fossil fuel such as coal
`generates flue gas that contains mercury and other trace
`elements that originate from the fuel. The release of the
`mercury (and other pollutants) to the environment must be
`controlled by use of sorbents, scrubbers, filters, precipitators,
`and other removal technologies.
`Id. at 1:54–59.
`The ’218 patent acknowledges that “[s]everal types of mercury
`control methods for flue gas have been investigated, including injection of
`fine sorbent particles into a flue gas duct and passing the flue gas through a
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`Patent 10,926,218 B2
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`sorbent bed.” Id. at 2:10–13. According to the ’218 patent, however, because
`sorbents in the existing carbon injection systems are initially unreactive, they
`“must be used in large amounts, at high sorbent -to-mercury ratios, to
`effectively capture the mercury.” Id. at 2:31–37. Thus, “there remains a need
`for more economical and effective mercury removal technology. ” Id.
`at 2:43–44.
`The ’218 patent describes a halogen/halide promoted activated carbon
`sorbent that is highly effective for the removal of mercury from flue gas
`streams. Id. at 2:56–58. According to the ’218 patent, “[t ]he sorbent
`comprises a new halide-modified carbon form containing a reactive
`compound produced by the reaction of bromine (or halide or other halogen)
`with the carbon .” Id. at 2:58–61.
`The ’218 patent states that “ [o]ptional secondary components and
`alkali may be added to further increase reactivity and mercury capacity,” and
`discloses that “the optional secondary component is selected from the group
`consisting of Group V halides, Group VI halides, HI, HBr, HCl, and
`combinations thereof.” Id. at 2:61–63, 3:40–43.
`The ’218 patent provides a promoted carbon sorbent “comprising a
`base activated carbon that has reacted with a promoter selected from the
`group consisting of halides, halogens, and combinations thereof. ” Id.
`at 3:3–6.
`The ’218 patent states that its invention “provides for cost -effective
`removal of pollutants including mercury, using sorbent enhancement
`additives and/or highly reactive sorbents, with contact times of seconds (or
`less), and that may be regenerated and reused. ” Id. at 2:44–48.
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`Patent 10,926,218 B2
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`D. Illustrative Claim
`Independent claim 1 is illustrative of the claimed subject matter and is
`reproduced below, with Petitioner’s designations of the limitations in
`brackets.
`1. [1(Pre)] A method of separating mercury from a mercury-
`containing gas, the method comprising:
`[1(a)] combusting coal in a combustion chamber, to provide the
`mercury-containing gas, wherein
`[1(b)] the coal comprises added HI, an iodide salt, or a
`combination thereof, added to the coal before the coal enters the
`combustion chamber, or
`the combustion chamber comprises added HI, an iodide salt, or
`a combination thereof, or
`a combination thereof;
`[1(c)] injecting a sorbent comprising activated carbon into the
`mercury-containing gas downstream of the combustion
`chamber,
`[1(d)] wherein a weight ratio of the HI, iodide salt, or the
`combination thereof added to the coal, added to the combustion
`chamber, or a combination thereof, to an amount of the sorbent
`injected into the mercury-containing gas is from about 1:100 to
`about 30:100;
`[1(e)] contacting mercury in the mercury-containing gas with
`the sorbent; and
`[1(f)] separating the sorbent contacted with the mercury from
`the mercury -containing gas.
`Ex. 1001, 35:61–36:14.
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`Patent 10,926,218 B2
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`E. Asserted Challenges to Patentability
`Petitioner assert s the following challenges to patentability:
`Claims Challenged 35 U.S.C. § Reference
`1–4, 6–9, 13–17,
`20–25
`102 Baldrey4
`1–4, 6–26 103 Baldrey, Olson-2355
`1–4, 6–26 103 Baldrey, Olson-6466
`1–4, 6–26 103 Sjostrom, 7 Olson-235
`1–4, 6–26 103 Sjostrom, Olson -646
`1–4, 6–26 103 Sjostrom, Olson -235, Olson-2798
`1–4, 6–26 103 Sjostrom, Olson -646, Olson-279
`In support of the unpatentability challenges, Petitioner relies on the
`Declaration of Stephen Niksa, Ph.D. (Ex. 1002).
`II. ANALYSIS OF ASSERTED GROUNDS
`A. Level of Ordinary Skill in the Art
`In determining the level of ordinary skill in the art, various factors
`may be considered, including the “type of problems encountered in the art;
`prior art solutions to those problems; rapidity with which innovations are
`made; sophistication of the technology; and educational level of active
`workers in the field.” In re GPAC, Inc., 57 F.3d 1573, 1579 (Fed. Cir. 1995).
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`4 US 2011/0030592 A1, published Feb. 10, 2011, Ex. 1015 (“Baldrey).
`5 US 8,652,235 B2, issued Feb. 18, 2014, Ex. 1018 (“Olson-235”).
`6 US 2006/0048646 A1, published Mar. 9, 2006, Ex. 1012 (“Olson-646”).
`7 Sjostrom, Sharon, Full Scale Evaluations of Mercury Control Technologies
`with PRB Coals, Track A, Session A3 (Mercury – Control), Presentation
`A3b, EUEC: 8TH ELECTRIC UTILITIES ENVIRONMENTAL CONFERENCE
`(Tucson, Arizona: January 25, 2005), Ex. 1010 (“Sjostrom).
`8 US 2014/0255279 A1, published Sept. 11, 2014, Ex. 1016 (“Olson-279”).
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`Furthermore, the prior art itself can reflect the appropriate level of ordinary
`skill in the art. Okajima v. Bourdeau, 261 F.3d 1350, 1355 (Fed. Cir. 2001).
`Petitioner assert s that “[a] person of ordinary skill in the art
`(‘POSITA’) would have at least a bachelor’s degree in chemical
`engineering, mechanical engineering, or a related field of study with at least
`two years of experience implementing pollution control in power generation
`plants for natural gas, coal, and/or industrial waste incineration.” Pet. 11–12
`(citing Ex. 1002 ¶¶ 48–51). Patent Owner does not dispute the level of
`ordinary skill in the art . See generally Prelim Resp.
`For purposes of this Decision, we adopt Petitioner’s proposed
`definition of a POSITA because it is consistent with the skill level reflected
`in the disclosures of the ’218 patent and prior art . See Okajima, 261 F.3d
`at 1355 (the prior art may reflect an appropriate level of skill in the art).
`B. Claim Construction
`In an inter partes review, we construe a claim term “using the same
`claim construction standard that would be used to construe the claim in a
`civil action under 35 U.S.C. [§] 282(b).” 37 C.F.R. § 42.100(b). Under that
`standard, the words of a claim “are generally given their ordinary and
`customary meaning,” which is “the meaning that the term would have to a
`person of ordinary skill in the art in question at the time of the invention, i.e.,
`as of the effective filing date of the patent application.” Phillips v. AWH
`Corp., 415 F.3d 1303, 1312–13 (Fed. Cir. 2005) (en banc).
`Claim terms need only be construed to the extent necessary to resolve
`the controversy. Wellman, Inc. v. Eastman Chem. Co., 642 F.3d 1355, 1361
`(Fed. Cir. 2011). On this record and for purposes of this Decision, we see no
`need to construe any claim term expressly.
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`C. Priority Analysis
`The ’218 patent issued from Application No. 16/509,071
`(“the ’071 Application”), filed July 11, 2019. Ex. 1001, codes (21), (22).
`Each of t he references asserted in this proceeding (Sjostrom (2005),
`Olson-646 (2006), Baldrey (2011), Olson -235 (2014), and Olson -279
`(2014)) predates the filing date of the ’071 Application.
`The ’071 Application, however, claims priority, through several
`earlier non-provisional applications, to Application No. 60/605,640
`(“the Provisional Application”), filed August 30, 2004 (Ex. 1001, code (60)),
`which predates all the asserted references. Thus, if the challenged claims of
`the ’218 patent were entitled to the priority date of the Provisional
`Application, none of the asserted references would qualify as prior art.
`In addition, if the challenged claims of the ’218 patent were entitled to
`the priority date of some of the non -provisional applications, which were
`filed in 2005, 2008, 2009, 2012, and 2013, certain asserted references would
`not qualify as prior art either.
`A patent’s claims, however, “are not entitled to an earlier priority date
`merely because the patentee claims priority. Rather, for a patent’s claims to
`be entitled to an earlier priority date, the patentee must demonstrate that the
`claims meet the requirements of 35 U.S.C. § 120.” In re NTP, Inc. ,
`654 F.3d 1268, 1276 (Fed. Cir. 2011) (citations omitted). Under § 120,
`a claim is entitled to the priority to a prior application’s filing date only if the
`prior application discloses the claimed invention “in the manner provided
`by [§] 112(a) (other than the requirement to disclose the best mode).”
`Section 112(a) in turn requires the specification to, among other thing s,
`contain a written description of the claimed invention.
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`The test for sufficiency of a written description under 35 U.S.C.
`§ 112(a) is whether the earlier application’s disclosure “reasonably conveys
`to those skilled in the art that the inventor had possession of the claimed
`subject matter as of the filing date.” Ariad Pharms., Inc. v. Eli Lilly & Co. ,
`598 F.3d 1336, 1351 (Fed. Cir. 2010) (en banc). That test “requires an
`objective inquiry into the four corners of the specification from the
`perspective of a person of ordinary skill in the art.” Id.
`In an inter partes review, although the p etitioner has the ultimate
`burden of persuasion to prove unpatentability, the p atent owner must
`demonstrate entitlement to a priority date when the p atent owner relies on
`that priority date to overcome an anticipation or obviousness argument. See
`Dynamic Drinkware, LLC v. Nat’l Graphics, Inc., 800 F.3d 1375, 1379–80
`(Fed. Cir. 2015).
`On the current record, and for purposes of this Decision, we find
`record evidence does not show that the challenged claims of the ’218 patent
`are entitled to a priority date before 2018.
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`Petitioner provides the following family tree of the ’ 218 patent:
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`Pet. 20.
`The parties group these applications into three categories: the
`Provisional Application ; the applications filed before April 12, 2018
`(“Pre-2018 Applications”), and the applications filed on or after April 12,
`2018 (“Post-2018 Applications”). See, e.g., Prelim. Resp. 9.
`This grouping reflects Petitioner’s assertion that Application
`No. 15/951,970 (“the ’970 application”), filed in April 2018, made
`“extensive” changes to the specification. Pet. 20 (citing Ex. 1064
`(comparison of the ’970 application to the immediately prior application)).
`According to Petitioner, limitations “directed to what halide compounds are
`added and where they are added,” which Petitioner term s
`“Newly-Introduced Limitations,” do not have written-description support in
`applications before the ’970 applications. Id. at 21. Petitioner argues that
`before April 2018, when the ’970 application was filed, a POSITA “would
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`not have concluded Applicants were in possession of the subject matter of
`the issued claims of the ’218 Patent.” Id. Thus, Petitioner contend s that
`Patent Owner is not entitled to a priority date before April 2018. Id. at 22.
`Patent Owner disagrees with Petitioner. Prelim. Resp. 7–26. The
`parties dispute (1) whether the Pre-2018 Applications provide express
`support for Newly-Introduced Limitations; and (2) whether the Provisional
`Application provides sufficient written -description support for the
`Newly-Introduced Limitations. Pet. 23–25, 33–36; Prelim. Resp. 9–13, 16.
`On this record, we find Petitioner’s arguments more persuasive.9 We address
`these arguments in turn.
`1. Pre-2018 Applications
`Each of independent claims 1 and 26 recites
`the coal comprises added HI, an iodide salt, or a combination
`thereof, added to the coal before the coal enters the combustion
`chamber, or
`the combustion chamber comprises added HI, an iodide salt, or
`a combination thereof, or
`a combination thereof.
`Ex. 1001, 35:65–36:3, 38:12–17. Similarly, independent claim 25 recites
`“the coal comprising an additive comprising added HI, an iodide salt, or a
`combination thereof . . . the HI, iodide salt, or the combination thereof added
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`9 The parties also dispute whether the Provisional Application was
`incorporated by reference into the Pre-2018 Applications. Pet. 26–33;
`Prelim. Resp. 14–15. We do not need to resolve this issue because as
`explained below, even if all the disclosures of Provisional Application were
`considered, they would not provide written -description support for the
`challenged claims. See infra Section II.C.2.
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`to the coal, added to the combustion chamber, or a combination thereof.” Id.
`at 37:39–41, 38:3–5.
`Petitioner contend s that
`[t]he Pre-2018 Applications do not support adding any halides
`to the coal or combustion chamber, let alone the HI, iodide salt,
`or combination thereof claimed in the ’218 Patent . Rather, the
`Pre-2018 Applications are directed to preparing brominated-
`activated carbon . . . outside mercury-containing flue gas . . . ,
`and then injecting the pre -brominated sorbent into
`mercury-containing flue gas . . . downstream from the
`combustion chamber.
`Pet. 23–24.
`Patent Owner argues that paragraph 56 of the Pre-2018 Applications10
`discloses adding bromine to the coal in the combustion chamber by
`disclosing “the practice of adding the promotor and sorbent at one or
`multiple locations.” Prelim. Resp. 16.
`The Board previously addressed this issue in IPR2020-00832:
`Paragraph 56 explains that “single injection points 116 or 119
`are shown in Figure 3, although one skilled in the art will
`understand that multiple injection points are within the scope of
`the present invention.” Ex. 1022, 11, ¶ 56. However, this refers
`to injection points in flue gas stream 15 described in paragraph
`55 of the ’595 application, not multiple injection points at
`different points in the process (e.g., in the flue gas stream, in
`the combustion chamber, or with coal). Id. at 10–11, ¶ 55.
`Further , to the extent Patent Owner argues there is written
`description support in the [Pre-2018 Applications] for adding
`the promoter to the coal or to the combustion chamber . . .
`because this would have been an obvious variation of the ’595
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`10 Patent Owner states that the “Pre-2018 Applications contain substantively
`identical disclosures” and cites to the Application No. 12/201,595
`(“the ’595 Application,” Ex. 1022) as representative. Prelim. Resp. 14. For
`convenience, we do the same.
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`application’s disclosure, rendering an invention obvious does
`not satisfy the written description requirement.
`IPR2020-00832, Paper 17, 28–29.
`On the current record, and for purposes of institution, we agree with
`the Board’s previous determination and adopt it as our own.
`Patent Owner acknowledges that the Pre-2018 Applications do “not
`contain provisional figure 2,” but argues that they do “ provide a similar
`disclosure of bromine species being added to coal. ” Prelim. Resp. 16.
`Specifically, Patent Owner points to the Pre-2018 Applications for
`disclosing an example, in which “the halogen/halide promoted carbon
`sorbent was injected into the flue gas after the boiler. In general, however,
`the inventive sorbent can be injected where desired (e.g., before, after, or
`within the b oiler).” Id. (citing Ex. 1022 ¶ 107).
`Patent Owner argues that “[b]ecause a halogen/halide promoted
`sorbent necessarily includes a halogen/halide such as HI and iodide salts, a
`POSITA would recognize that adding this material before the boiler
`necessarily results in the limitations at issue in the ’218 Patent. ” Id. The
`Board addressed this issue in IPR2020-00832 too:
`For this example [described in ¶ 107], the ’595 application
`discloses “the halogen/halide promoted carbon sorbent was
`injected into the flue gas after the boiler.” Id. Thus, this passage
`describes a combination of promoter and sorbent material being
`added at one single point: “into the flue gas after the boiler.”
`The ’595 application continues the description of this example
`by stating “[i]n general however, the inventive sorbent can be
`injected where desired (e.g., before, after, or within the boiler).”
`Id. Although this describes other injection points (“e.g., before,
`after, or within the boiler”), this disclosure regards the
`promoted sorbent material. As a result, it describes the addition
`of both the promoter and the sorbent material at a single point,
`not (1) the addition of the promoter with the coal or the
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`combustion chamber and (2) the injection of the sorbent
`material into mercury-containing gas downstream of the
`combustion chamber. . . . As a result, we do not agree with
`Patent Owner’s arguments regarding paragraph 107 of
`the ’595 application.
`IPR2020-00832, Paper 17 at 28.
`On the current record, and for purposes of institution, we agree with
`the Board’s previous analysis and adopt it as our own.
`Furthermore, as Petitioner points out, in the Pre -2018 Applications,
`“[t]he only mention of halide salts (of which iodide salts are a subset) is of
`criticism.” Pet. 24. Indeed, the Pre-2018 Applications disclose that “[h]alides
`are considered reduced forms that do not, alone, oxidize other compounds.
`In the conventional view therefore, a halide-salt-treated activated carbon will
`not effectively oxidize elemental mercury and capture elemental mercury.”
`Ex. 1022, 269. This evidence tends to support Petitioner’s argument that the
`Pre-2018 Applications do not provide support for adding iodide salt, or a
`combination of HI and iodide salt, to the coal or combustion chamber. Pet.
`24.
`In sum, the current record supports that the Pre-2018 Applications, at
`least, do not expressly disclose adding iodide salts or a combination of HI
`and iodide salt to the coal in the combustion chamber. Thus, Patent Owner
`has not shown that the Pre -2018 Applications provide sufficient
`written-description support for the challenged claims.
`2. Provisional Application
`Petitioner argues that the Provisional Application does not support
`two aspects of the challenged claims: (1) the claimed genus of “HI, an iodide
`salt, or a combination thereof;” and (2) adding the claimed genus to the coal
`“before the coal enters the combustion chamber.” Pet. 33–36.
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`a. The Claimed Genus
`As support for the claimed genus of “HI, an iodide salt, or a
`combination thereof,” Patent Owner points to the following disclosure in the
`Provisional Application as explaining “the scientific basis for the invention:”
`We now teach that the formation of the new bromide compound
`with carbon increases the reactivity of the carbon forms toward
`mercury and other pollutants. The resulting bromide compound
`is uniquely suited to facilitate oxidation of the mercury. The
`effectiveness of the oxidation results from the promotion
`effect of the halide exerted on the developing positive charge
`on the mercury during the oxidation, known in the chemical art
`as a specific catalytic effect. Thus, as the mercury electrons
`are drawn toward the positive carbon, the halide anion
`electrons are pushing in from the other side, which stabilizes
`the positive charge developing on the mercury and lowers the
`energy requirement for the oxidation process. Bromide is
`especially reactive, owing to the highly polarizable electrons in
`the outer 4p orbitals of the ion. Thus, adding HBr or Br
`2 to the
`carbon forms a similar carbon bromide, in which the positive
`carbon oxidizes the mercury with the assistance of the bromide
`ion.
`Prelim. Resp. 9–10 (ci ting Ex. 1020, 7 –811).
`From this disclosure, Patent Owner contends that “the benefits of the
`claimed promoted sorbent are obtained by forming a carbon halide (for
`example, a bromide) out of activated carbon and a negative halogen ion, i.e.,
`Br-.” Id. at 10. In addition, “this bromine Br- ion may be supplied by adding
`HBr or Br2 (both of which contain Br-) to the carbon .” Id. According to
`Patent Owner, the Provisional Application thus teaches that “[w]hen these
`components are mixed into mercury-containing gas, the mercury (Hg) is
`
`11 We cite the native page number of the Provisional Application, not the
`page number of the Exhibit provided by Petitioner.
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`Patent 10,926,218 B2
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`drawn toward the carbon, and the Bromine ion is drawn toward the mercury,
`creating a stable bond.” Id. at 11. We are not persuaded by Patent Owner’s
`argument.
`On the current record, it is unclear to what extent, if at all, the alleged
`“scientific basis for the invention” describes adding bromine to coal. Written
`description requires more than that the disclosure renders the claimed
`subject matter obvious. Lockwood v. Am. Airlines, Inc., 107 F.3d 1565,
`1571–72 (Fed. Cir. 1997) (“The question is not whether a claimed invention
`is an obvious variant of that which is disclosed in the specification. Rather, a
`prior application itself must describe an invention.”); PowerOasis, Inc. v.
`T-Mobile USA, Inc., 522 F.3d 1299, 1306 (Fed. Cir. 2008) (“Entitlement to a
`filing date does not extend to subject matter which is not disclosed, but
`would be obvious over what is expressly disclosed.”).
` Patent Owner points to the following disclosure of using an optional
`second component as providing support for the claimed genus:
`It has been demonstrated that addition of an optional second
`component, in addition to the bromine, results in improved
`reactivity and capacity for the sorbent, exceeding that of both
`the untreated carbon and the brominated carbon. The second
`compound comprises either a second halogen or a compound
`from a second halogen, such as HBr.
`Prelim. Resp. 11–12 (quoting Ex. 1020, 10 12).
`Patent Owner also points to provisional example 1E as disclosing
`“additional substance is a compound comprised of a Group V or VI element
`or combination of Group V or VI with Group VII element, such as SCl2,
`
`12 Patent Owner’s Preliminary Response cites page 12 of the Exhibit 1020.
`The cited passage appears at page 10. We deem this harmless error.
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`Patent 10,926,218 B2
`19
`1-10 wt% of bromine.” Prelim. Resp. 19. Because “a group VII element
`includes iodine,” Patent Owner interprets example 1E as disclosing “the use
`of various halogen-containing compounds.” Id. at 11, 19; Sur -reply 6–7.
`Patent Owner points to the Provisional Application as stating “[t]he
`sorbent that contains bromine is expected to be more reactive than the
`corresponding sorbent containing chlorine and much less expensive than the
`sorbent containing iodine.” Prelim. Resp. 13 (citing Ex. 1020, 13). Based on
`this disclosure, Patent Owner contends that “the inventors were plainly
`aware that the additive injection could include iodine as the halogen in use.”
`Id. We are not persuaded by Patent Owner’s argument.
`“It is not sufficient for purposes of the written description requirement
`of § 112 that the disclosure, when combined with the knowledge in the art,
`would lead one to speculate as to the modifications that the inventor might
`have envisioned, but failed to disclose.” Lockwood, 107 F.3d at 1572. Thus,
`what the inventors were aware of, but the specification does not disclose,
`does not constitute objective evidence to show written-description support.
`Patent Owner has not identified any disclosure in the Provisional
`Application of adding an iodide salt. In fact, the Provisional Application
`discloses that “[t]he h alide is considered a reduced form and cannot
`therefore oxidize anything by itself. It is for this reason that it is not obvious
`that a halide -halogen treated activated carbon would be effective at
`oxidizing elemental mercury and provide effective capture of elemental
`mercury. ” Ex. 1020, 7. This disclosure tends to support Petitioner’s
`argument that “the patentee taught not to use the category of halide salts.”
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`Patent 10,926,218 B2
`20
`Reply 8 (citing Ex. 1002 ¶ 178; Ex. 1020, 7 13); see also Ex. 1002 ¶ 178
`(Dr. Niksa’s testifying that “the Provisional suggests that the inventors had
`determined not to use halide salts (such as iodide salts)”).
`In addition, even though Example 1E of the Provisional Application
`discloses the claimed HI, that single species is insufficient to provide the
`written-description support for the claimed genus “HI, an iodide salt, or a
`combination thereof.” That is because the record shows that HI and an
`iodide salt have different properties. See, e.g., Ex. 1026 ¶¶ 11, 29
`(co-inventor Mr. Pavlish testifying during prosecution of the ’114 patent that
`HBr and HI “are gases that dissolve in water to give acids which are
`commonly known as hydrohalic acids,” whereas salt is “an ionic compound
`that can be formed by the neutralization reaction of an acid and a base”).
`Because the difference between HI and an iodide salt is such that the person
`skilled in the art would not readily discern that an iodide salt would perform
`similarly HI, “disclosure of more species is necessary to adequately show
`possession of the entire genus.” Bilstad v. Wakalopulos, 386 F.3d 1116,
`1125 (Fed. Cir. 2004).
`In sum, on this record, and for purposes of institution, Patent Owner
`has not sufficiently shown that the Provisional Application supports the full
`scope of the claimed genus.
`
`13 Page 8 of the Reply cites Exhibit 1010. The correct citation appears to be
`Exhibit 1020. In addition, t he quoted language allegedly from the
`Provisional Application is in fact from the Pre-2018 Applications. See
`Reply 8. Because the Provisional Application includes similar, although not
`identical, language (compare Ex. 1020, 7, with Ex. 1022, 269), we deem this
`harmless error. For future filings, we encourage the parties to provide
`accurate citation s to the record.
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`b. Adding