BAKER HUGHES INCORPORATEDDownload PDFPatent Trials and Appeals BoardMay 1, 202014029520 - (D) (P.T.A.B. May. 1, 2020) Copy Citation UNITED STATES PATENT AND TRADEMARK OFFICE UNITED STATES DEPARTMENT OF COMMERCE United States Patent and Trademark Office Address: COMMISSIONER FOR PATENTS P.O. Box 1450 Alexandria, Virginia 22313-1450 www.uspto.gov APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO. 14/029,520 09/17/2013 Andreas Brandl 020569-30900 (54711-US) 1106 71762 7590 05/01/2020 JONES DELFLACHE LLP 1333 HEIGHTS BOULEVARD SUITE 300 HOUSTON, TX 77008 EXAMINER SUE-AKO, ANDREW B. ART UNIT PAPER NUMBER 3674 MAIL DATE DELIVERY MODE 05/01/2020 PAPER Please find below and/or attached an Office communication concerning this application or proceeding. The time period for reply, if any, is set in the attached communication. PTOL-90A (Rev. 04/07) UNITED STATES PATENT AND TRADEMARK OFFICE BEFORE THE PATENT TRIAL AND APPEAL BOARD Ex parte ANDREAS BRANDL, CHRISTINA MAGELKY, ANGELA ANH DOAN, and WINDAL SCOTT BRAY Appeal 2019-004760 Application 14/029,520 Technology Center 3600 Before JENNIFER D. BAHR, JAMES P. CALVE, and JILL D. HILL, Administrative Patent Judges. BAHR, Administrative Patent Judge. DECISION ON APPEAL STATEMENT OF THE CASE Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the Examiner’s decision to reject claims 1–4, 24, 26, 31, 33, 34, 38, and 40–47.2 We have jurisdiction under 35 U.S.C. § 6(b). We AFFIRM IN PART. 1 We use the word “Appellant” to refer to “applicant” as defined in 37 C.F.R. § 1.42. Appellant identifies the real party in interest as “Baker Hughes Incorporated, a GE company, LLC.” Appeal Br. 1. 2 Appellant canceled claims 14, 29, 30, 32, 36, 37, and 39 subsequent to the Final Action. See Advisory Act. (Jan. 15, 2019). Appeal 2019-004760 Application 14/029,520 2 CLAIMED SUBJECT MATTER Appellant’s invention is directed to “a method of delaying viscosification of a well treatment fluid by use of particulates having a minimum of 40% retention on a 60 mesh screen and a minimum of 1% retention on a 20 mesh screen.” Spec. ¶ 1. Claims 1, 38, and 40 are independent. Appeal Br. 17–19 (Claims App.). Claim 1, reproduced below, is illustrative of the claimed subject matter. 1. A method of delaying viscosification of a cementitious slurry during the cementing of a pipe or casing in a wellbore, the method comprising including in the cementitious slurry a hydratable polymeric viscosifying agent selected from the group consisting of underivatized guar, hydroxypropyl guar, carboxymethyl hydroxypropyl guar, xanthan, hydroxyethyl cellulose, methylhydroxyethyl cellulose, carboxymethyl cellulose, carboxymethylhydroxy cellulose, carboxymethyl hydroxyethyl cellulose, hydroxyethylmethyl cellulose, ethylhydroxyethyl cellulose, ethylmethylhydroxyethyl cellulose, hydroxypropyl cellulose, hydroxyethylpropyl cellulose, dialkyl carboxymethyl cellulose, polyvinyl alcohols, acrylamidomethylpropane sulfonic acid and salts thereof, the hydratable polymeric viscosifying g agent comprising particulates having a minimum of 40% retention on a 60 mesh screen and a minimum of 1% retention on a 20 mesh screen, introducing the cementitious slurry containing the hydratable polymeric viscosifying agent into the wellbore and cementing the pipe or casing in the wellbore with the cementitious slurry to form a cement sheath. Appeal 2019-004760 Application 14/029,520 3 EVIDENCE The prior art relied upon by the Examiner is: Name Reference Date Chang US 6,165,947 Dec. 26, 2000 Creel US 2006/0213662 A1 Sept. 28, 2006 Reddy US 2012/0090841 A1 Apr. 19, 2012 Gunnar DeBruijn et al., High-Pressure, High-Temperature Technologies, Oilfield Review 46, 46–60 (Autumn 2008) (hereinafter DeBruijn). REJECTIONS I. Claims 43, 45, and 46 stand rejected under 35 U.S.C. § 112(b) as indefinite. II. Claims 38, 42, and 47 stand rejected under 35 U.S.C. § 102(a)(1) as anticipated by Reddy. III. Claims 33, 34, and 43–45 stand rejected under 35 U.S.C. § 103 as unpatentable over Reddy. IV. Claims 1, 2, 4, 24, 26, and 31 stand rejected under 35 U.S.C. § 103 as unpatentable over Reddy and Chang. V. Claims 40 and 41 stand rejected under 35 U.S.C. § 103 as unpatentable over Reddy, DeBruijn, and Chang.3 VI. Claim 3 stands rejected under 35 U.S.C. § 103 as unpatentable over Reddy, Chang, and Creel. 3 We interpret the Examiner’s reference to “Reddy as in claim 32” in the statement of the rejection of claims 40 and 41 to mean Reddy in view of DeBruijn because claim 32 (prior to its cancellation and re-writing of its dependent claim 40 in independent form) was rejected based on Reddy in view of DeBruijn. See Final Act. 4, 7; see also Appeal Br. 14 n.1 (noting that the Examiner included DeBruijn in rejecting claim 32). Appeal 2019-004760 Application 14/029,520 4 VII. Claim 46 stands rejected under 35 U.S.C. § 103 as unpatentable over Reddy and Creel. OPINION Rejection I—Indefiniteness The Examiner rejects claim 43, as well as claims 45 and 46, which depend from claim 43, as indefinite because, according to the Examiner, “one of ordinary skill in the art would not be reasonably apprised of the scope of [‘water-insoluble adsorbent’] in terms of what materials are and are not necessarily encompassed by [this term].” Final Act. 2 (underlining omitted). In explaining the basis of the rejection, the Examiner states that “‘water-insoluble adsorbent’ is a functional limitation and also not a typical name of any established grouping/class in the art, especially one comprising the range of disclosed materials, which don’t appear to necessarily share a clear common structure or property.” Id. (referring to the “[s]uitable water- insoluble adsorbents” listed in paragraph 44 of Appellant’s Specification). The Examiner adds that “the disclosure only relates to these ‘water-insoluble adsorbents’ to which the ‘polymeric hydratable viscosifying agent may be adsorbed.’” Id. Appellant takes issue with the Examiner’s characterization of the phrase “water-insoluble adsorbent” as functional language. Appeal Br. 5. Appellant submits that “the phrase ‘water-insoluble adsorbent’ refers to a structure of a component onto which is adsorbed the claimed hydratable polymeric viscosifying agent.” Id. at 5–6. According to Appellant, The common meaning of the word “adsorbent” is a solid substance that adsorbs another substance. The phrase “water- insoluble” modifies the adsorbent, i.e., it limits the adsorbent to Appeal 2019-004760 Application 14/029,520 5 those which are water-insoluble. Thus, the phrase “water- insoluble adsorbent” references an adsorbent which is water- insoluble. As used in the claims of Appellant, the adsorbent is the substance onto which the hydratable polymeric viscosifying agent is adsorbed. Id. at 6. Appellant argues that the “[t]he issue is whether the phrase ‘water- insoluble adsorbent’ provides enough certainty to one of skill in the art when read in the context of the invention.” Id. (citing Interval Licensing LLC v. AOL Inc., 766 F.3d 1364, 1370 (Fed. Cir. 2014)). In this case, Appellant contends that “Appellant has provided a standard for assessing a ‘water-insoluble adsorbent’ based on the common usages of the word ‘adsorbent’ and ‘water-insoluble’ coupled with the description in the specification, e.g., the adsorbent is the surface onto which the polymeric viscosifying agent is adsorbed.” Id. at 6–7. In response, the Examiner states that the term “adsorbent” is functional language because it describes the structure by what it does (i.e., “describing that which is capable of adsorbing (or collecting and holding)”), not what it is. Ans. 4. The Examiner finds that “Appellant’s disclosure has provided no clear standard for ascertaining what are ‘adsorbents’ vs. what are not ‘adsorbents.’” Id. at 5. The Examiner queries, “[f]or example, at what capability of collecting and holding does a solid become an adsorbent?” Id. Appellant correctly characterizes the issue as “whether one of skill in the art would be apprised of the meaning of the phrase ‘water-insoluble adsorbent’ (using the standard dictionary [definition] of ‘adsorbent’ or ‘adsorb’) when the claims are read in light of the Specification and in light of the person skilled in the art.” Reply Br. 4. Claims, when read in light of Appeal 2019-004760 Application 14/029,520 6 the specification, must “reasonably apprise those skilled in the art both of the utilization and scope of the invention” using language “as precise as the subject matter permits.” In re Packard, 751 F.3d 1307, 1313 (Fed. Cir. 2014). In determining whether a claim is definite under 35 U.S.C. § 112(b), “[t]he USPTO, in examining an application, is obliged to test the claims for reasonable precision according to [this principle].” Id. Appellant submits that “[t]he Examiner does not state and has provided no evidence that one of skill in the art would not understand the meaning of ‘adsorbent’, ‘water- insoluble’ or ‘water-insoluble adsorbent’.” Reply Br. 4. According to Appellant “[t]he Examiner’s position is premised on his perception that one of skill in the art would have been unable to recognize a material which is adsorbent versus non-adsorbent.” Id. Appellant adds that “[t]he claimed terminology . . . is not complicated and no reason is provided as to why one of skill in the art would be unable to recognize an adsorbent from a non- adsorbent.” Id. Appellant also acknowledges that a myriad of different components are used in the oilfield art for different purposes, but points out that “the Examiner does not state cements, calcium carbonate[,] and crosslinked polymers are known adsorbents in oilfield chemistry.” Reply Br. 5–6 (emphasis added). Appellant also notes that “the Specification (para. 00044) provides exemplary water-insoluble adsorbents onto which the claimed polymeric hydratable viscosifying agent may be absorbed” and contends that “[t]here is no requirement that Appellant provide an exhaustive list of species of adsorbents and the fact a large number of substances may be within the phrase ‘water-insoluble adsorbent’ does not render the claims indefinite.” Id. at 6. Appellant further contends that Appellant “has Appeal 2019-004760 Application 14/029,520 7 provided a standard for measuring the ‘degree’ of the claimed phrase by providing the weight ratio of the viscosifying agent to the water-insoluble adsorbent as well as the amount of viscosifying polymer in the cementitious slurry (Specification, paras. 00044-00045).” Id. at 8. Even taking into account the Examiner’s point, which is not without merit, that different materials may have different degrees of adsorbency and, thus, to some extent, the term “adsorbent” is a term of degree, the Examiner does not set forth sufficient evidentiary findings or technical explanation to establish a reason to believe that a person of ordinary skill in the art would not be reasonably apprised of the scope of the claimed subject matter (particularly, the scope of “the hydratable polymeric viscosifying agent [being] adsorbed onto a water-insoluble adsorbent”) when the language in question is read in light of the Specification and in the context of the claim as a whole. In particular, given the common meanings of “water-insoluble” and “adsorbent,” as Appellant submits, “the phrase ‘water-insoluble adsorbent’ references an adsorbent which is water-insoluble.” Appeal Br. 6. “As used in the claims of Appellant, the adsorbent is the substance onto which the hydratable polymeric viscosifying agent is adsorbed.” Id. Further, Appellant’s Specification provides a non-exhaustive list of materials considered to be suitable water-insoluble adsorbents within the context of Appellant’s invention, as well as a range of typical weight ratios of polymeric hydratable viscosifying agent to water-insoluble adsorbent and a preferred range of the amount (in pounds) of viscosifying polymer. Spec. ¶¶ 44–45. Appellant’s Specification does not expressly enumerate all materials that are suitable “water-insoluble adsorbents,” but the aforementioned Appeal 2019-004760 Application 14/029,520 8 disclosure of paragraphs 44 and 45 of the Specification does provide guidance as to what is meant by this terminology, and the Examiner does not specifically explain why this guidance would not be sufficient to apprise one of ordinary skill in the art of the metes and bounds of this claim language. “As the statutory language of ‘particular[ity]’ and ‘distinct[ness]’ indicates, claims are required to be cast in clear—as opposed to ambiguous, vague, indefinite —terms.” In re Packard, 751 F.3d at 1313 (citation omitted). At the same time, this requirement is not a demand for unreasonable precision. The requirement, applied to the real world of modern technology, does not contemplate in every case a verbal precision of the kind found in mathematics. Nor could it do so in a patent system that actually works, in practice, to provide effective protection for modern-day inventions. Rather, how much clarity is required necessarily invokes some standard of reasonable precision in the use of language in the context of the circumstances. Id. For the above reasons, we do not sustain the rejection of claim 43, or claims 45 and 46 depending from claim 43, as indefinite. Rejection II—Anticipation: Reddy The Examiner finds that Reddy discloses the method of claim 38. See Final Act. 3–4. The Examiner cites Reddy’s disclosure in paragraph 16 of using a biopolymer in solid form, as granules, having a mesh size within one of three enumerated ranges, to support the finding that Reddy discloses the particulate size requirement of claim 38. See id. at 3. In particular, the Examiner focuses on “a mesh size of […] about 10” and finds that “10 mesh would have about 100% of particles retained on a 20 mesh screen.” Id. Appeal 2019-004760 Application 14/029,520 9 In contesting the rejection, Appellant points out, correctly, that Reddy discloses introducing into the wellbore “a cement composition containing the modified additive” (MBA), not the biopolymer (hydroxyethyl cellulose (HEC)) itself. Appeal Br. 8. Indeed, the Examiner recognizes that Reddy discloses introducing into the wellbore a “cementing composition compris[ing] a cementitious material, water, an MBA[,] and optional additives.” Final Act. 3 (citing Reddy ¶ 34). Reddy discloses that “the wellbore cementing composition comprises a cementitious material and a modified biopolymer additive (MBA),” and that “the MBA is a reaction product of a polymer and an organic carbonate.” Reddy ¶ 11. According to Reddy, in one embodiment, “a reaction mixture for the preparation of an MBA comprises . . . a biopolymer,” such as “derivatized polysaccharides such as hydroxyethyl cellulose (HEC).” Id. ¶ 12. Reddy discloses that “a biopolymer suitable for use in this disclosure is in the solid form (e.g., as granules) and may have a mesh size of from about . . . 10 to about 190 . . . .” Id. ¶ 16. “[A] method of preparing an MBA . . . comprises contacting [the] biopolymer . . . (e.g., HEC) and an organic carbonate . . . to form a reaction mixture.” Id. ¶ 22. “[T]he reaction is carried out as a solid-state reaction such that the product (i.e., MBA) is a material in the solid state.” Id. ¶ 27; see also id. ¶¶ 25–26 (disclosing use of a non-aqueous solvent and a solid organic carbonate, followed by removal of the non-aqueous solvent, followed by introduction of the reaction mixture into a roller oven to expose it to reaction temperatures). Reddy theorizes that the MBAs produced “may be the product of an intra- and/or inter- molecular complex transesterification mechanism and not the product of a hydroxyalkylation reaction” and that “[t]he increased product viscosities for Appeal 2019-004760 Application 14/029,520 10 some MBAs may suggest the MBA has a molecular weight that is greater than that of the biopolymer starting reagent.” Id. ¶ 28. As Appellant correctly points out on page 8 of the Appeal Brief, paragraph 16 of Reddy discusses the mesh size of the biopolymer (e.g., HEC) that is reacted with an organic carbonate to form the MBA, and not the mesh size of the resulting MBA, which is used in the cementitious slurry. Reddy does not specifically disclose the particle size of the MBA. In response, the Examiner posits: A solid-state reaction reacting a solid with another solid would necessarily produce a solid product the same size or larger than the solid reactants, based on mass conservation. This is supported by Reddy’s observation about the MBA molecular weight being greater than the HEC biopolymer molecular weight. Therefore, it is a reasonable conclusion that Reddy’s starting HEC biopolymer of 10-190 mesh at least implies that the resultant MBA also has a mesh size of about 10-190 mesh. In other words, if the intermediate product is retained on the claimed mesh size, and mass is only added to form the final product, then the final product would also be retained on the claimed mesh size. Ans. 7. The Examiner does not cite any authority for the principle that “[a] solid-state reaction reacting a solid with another solid would necessarily produce a solid product the same size or larger than the solid reactants, based on mass conservation” (Ans. 7), much less provide any evidence or persuasive technical reasoning to support the conclusion that the particle size of one of the particulate reactants would be retained or increased in the resultant product. As Appellant points out, “an increase in molecular weight is not synonymous with an increase in particle size of the reaction product.” Appeal 2019-004760 Application 14/029,520 11 Reply Br. 10. Appellant asserts that “it is well known that solid state reactions are dependent on the area of contact between the reactant solids which is dependent on the total surface area of the reactants,” and, thus, “solid state reactions are typically conducted by grinding the reactants in the reaction vessel, i.e., during the reaction stage,” thereby reducing the particle size. Id. Appellant does not direct our attention to any reliable source to substantiate this assertion about how solid state reactions are typically conducted, much less present any evidence that the solid state reaction producing the MBA in Reddy necessarily is carried out by grinding. Nevertheless, Appellant’s recognition that an increase in molecular weight is not synonymous with an increase in particle size and observations about how the solid state reaction may be carried out sufficiently highlight that the Examiner’s finding regarding the particle size of the MBA lacks the requisite evidentiary underpinning to establish anticipation. Accordingly, we do not sustain the rejection of claim 38, or claims 42 and 47, which depend from claim 38, as anticipated by Reddy. Rejection III—Obviousness: Reddy Claims 33 and 34: The aforementioned deficiency in the rejection of claim 38 as anticipated by Reddy also pervades the rejection of claims 33 and 34, which depend from claim 38. See Final Act. 14. The Examiner’s additional findings and reasoning regarding the consistency of the slurry do not make up for the shortcomings discussed above. See id. Accordingly, we do not sustain the rejection of claims 33 and 34 as unpatentable over Reddy. Appeal 2019-004760 Application 14/029,520 12 Claims 43–45: Claim 43 depends from claim 38 and further recites that “the hydratable polymeric viscosifying agent is adsorbed onto a water-insoluble adsorbent.” Appeal Br. 20 (Claims App.). In rejecting claim 43, as well as claims 44 and 45, which depend from claim 43, the Examiner finds that Reddy teaches adjusting the viscosity of the MBA-containing cement composition (MBAC) using one or more encapsulated basic materials, which are designed to be released from encapsulation and contact the MBAC after it reaches a desired wellbore depth or area of the formation. Final Act. 14 (citing Reddy ¶ 37); see also Reddy ¶ 34 (explaining what is meant by MBAC). The Examiner also finds that Reddy teaches that the basic material comprises an aqueous solution and is encapsulated in a particulate solid material that remains dry and free flowing after adsorbing the basic material, and the basic material slowly diffuses through the particulate solid material. Final Act. 14 (citing Reddy ¶ 37). The Examiner notes, in particular, that Reddy discloses that examples of suitable particulate solid materials include “diatomaceous earth, zeolites, silica, alumina, metal salts of alumino-silicates, [and] clays.” Id. (underlining omitted) (citing Reddy ¶ 38). The Examiner determines that, in view of the aforementioned teachings of Reddy in paragraphs 37 and 38, “[i]t would clearly be advantageous for the encapsulated basic material to be packaged together with the MBA, so it can readily contact the MBA upon release from the encapsulation and lead to further viscosification.” Final Act. 15. Thus, according to the Examiner, it would have been obvious to adsorb the hydratable viscosifying agent “onto a water-soluble adsorbent (that is Appeal 2019-004760 Application 14/029,520 13 encapsulating the basic material), wherein the water-insoluble material is selected from the group consisting of . . . silica, particulates, precipitated silicas, silica, alumina, silica-alumina, . . . zeolites, diatomaceous earth, . . . and clays and mixtures thereof,” in order to allow “‘even further viscosification of the composition’ after it has reached a desired wellbore depth and/or has been placed into a desired area of the formation.” Id. Appellant points out that Reddy does not disclose or imply that the MBA is adsorbed onto the solid porous material. Appeal Br. 11. Rather, as Appellant points out, Reddy discloses the basic material being absorbed into the solid porous material and then being released by diffusion through the porous material to contact the MBA. Id.; see Reddy ¶¶ 37, 38. The Examiner’s obviousness rejection of claims 43–45 based on Reddy suffers from the same shortcoming as the rejection of claim 38 as anticipated by Reddy, namely, with respect to the unsupported finding regarding the retention of particulates of the hydratable polymeric viscosifying agent in the cementitious slurry (i.e., the MBAC). Reddy’s teachings regarding use of an encapsulated basic material to increase viscosification are directed to the basic material contacting the MBA (the reaction product), not contacting the biopolymer (e.g., HEC) used to form the MBA. As discussed above, the Examiner’s finding regarding the particle size (and, thus, retention percentage on a 60 mesh or 20 mesh screen) of the MBA lacks the requisite evidentiary underpinning. Moreover, Reddy mentions nothing about adsorbing the MBA, or any reactant used to form the MBA, onto the encapsulated basic material to permit contact with the basic material. Reddy only discloses absorbing the aqueous solution (basic material) such that it slowly diffuses through the Appeal 2019-004760 Application 14/029,520 14 particulate solid material to eventually contact the MBA to further adjust the viscosity of the MBA after it has reached the desired wellbore depth or area of the formation. Reddy ¶¶ 37–38. In other words, Reddy does not appear to be suggesting use of the encapsulated basic material to hasten the contact of the basic material with the MBA. In fact, Reddy suggests that it may be desirable “[t]o delay the reaction even longer” by placing on the porous solid material “an external coating of a polymeric material through which an aqueous solution slowly diffuses.” Reddy ¶ 38. Thus, Reddy does not appear to contemplate adsorbing the MBA onto the porous solid material (with the basic material encased therein), and it is not clear why a person having ordinary skill in the art would have been prompted to do so. Accordingly, we do not sustain the rejection of claims 43–45 as unpatentable over Reddy. Rejections IV and V—Obviousness: Reddy/Chang and Reddy/Debruijn/Chang Independent claims 1 and 40 specify that the hydratable polymeric viscosifying agent is “selected from the group consisting of” an enumerated list including, among others, “hydroxyethyl cellulose.” Appeal Br. 17, 19 (Claims App.). The Examiner finds that Reddy only discloses the biopolymers disclosed in paragraph 12 (which include HEC) “that are modified with carbonate to be MBA’s ([0011]), wherein ‘the MBAC may form a mass that plugs the zone at elevated temperatures, such as those found at higher depths within a wellbore’ ([0045]).” Final Act. 7, 9. However, the Examiner “observes that hydroxyethylcellulose (HEC) and acrylamidomethylpropanesulfonic acid (AMPS), among many other Appeal 2019-004760 Application 14/029,520 15 polymers and salts thereof, are all considered obvious variants of swellable polymers for viscosification, in the art.” Final Act. 8, 9. For example, the Examiner finds that Chang teaches a dry crosslinked polymer particulate system (Col. 13, line 50-Col. 15, line 6; also Col. 23, line 42-Col. 24, line 44), which when added to a treatment fluid “do not hydrate and thicken the water immediately, hence low friction pressure is observed while pumping” (Col. 14, lines 22-24) (i.e., they act as a delayed viscosification system) and “the material behaves as a solid fluid loss control material, such as the often used carbonate pill, but the particles form a tighter network on the face of the rock once they start to hydrate and expand” (Col. 14, lines 24-28), comprising “hydroxyethylcellulose (HEC)” (Col. 14, lines 1-13 and lines 35-36) which are “ground into fine particles or granules having a size of from about10 to about 200 meshes on the U.S. Sieve Series” (Col. 14, lines 19-21 ). Final Act. 8–10. The Examiner determines it would have been obvious to modify Reddy “to include swelling agents comprising ‘hydroxyethylcellulose polymer of ~10 mesh size, as in Chang, in order to ‘form a mass’ that ‘plugs the zone’ and ‘behaves as a solid fluid loss control material.’” Final Act. 8, 10. The Examiner reasons that “the modification is obvious as no more than the use of familiar elements (swellable polymers of ~10 mesh size as in Chang and Reddy) according to known techniques (cementing as in Reddy) in a manner that achieves predictable results (cementing with plugging of voids to reduce fluid loss).” Id. (citing KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 415–421 (2007). Appellant reiterates the deficiency of Reddy, discussed above, in regard to the claimed particulate size. Appeal Br. 13. Appellant also argues that Chang is not drawn to a method of cementing a well and does not even Appeal 2019-004760 Application 14/029,520 16 mention cementing of a well, much less forming a cement sheath. Id. Appellant elaborates that “[t]he Examiner has not sufficiently articulated a reason with a rational evidentiary underpinning to explain why, given the teachings of Reddy and Chang, one of skill in the art would have been prompted to modify the teachings of Reddy with the teachings of Chang,” and, further, “has not provided any reason to conclude that the HEC of Chang would be used with a cement.” Reply Br. 14 (italics omitted). Appellant contends, moreover, that “the combination of Reddy and Chang would not suggest use of the HEC of Chang as the MBA. At best, the combination of Reddy and Chang would suggest use of the HEC of Chang for reaction with the organic carbonate to produce the MBA.” Id. (italics omitted). In other words, according to Appellant, The combination of Reddy and Chang would not render a MBAC containing the HEC of Chang with a cementitious slurry. Rather, the combination of Reddy and Chang would only suggest a MBAC containing a cementitious slurry and a MBA prepared by reacting the HEC of Chang with an organic carbonate. Id. (italics omitted). Appellant’s argument that Chang does not disclose cementing a well is unavailing because, as the Examiner points out (Ans. 9), the Examiner relies on Reddy, and not Chang, for the cementing. Moreover, although Chang does not explicitly mention “cement” or “cementing,” Chang teaches that the dry crosslinked polymer particulate system disclosed therein may be used during “completion” operations, which persons of ordinary skill in the art would understand include both primary and secondary cementing operations. Chang 1:10–12; 4:30–33; 6:60–61; see Reddy ¶¶ 42, 43 Appeal 2019-004760 Application 14/029,520 17 (discussing primary and secondary cementing operations in well completion operations); id. ¶ 2 (discussing primary cementing “whereby cement slurry is placed in the annulus and permitted to set into a hard mass (i.e., sheath) to thereby attach the string of pipe to the walls of the wellbore and seal the annulus”); Creel ¶ 36 (explaining that well completion operations comprise primary and secondary cementing operations); Spec. ¶ 28 (describing “a typical cementing operation” in which “the cement slurry is pumped down the inside of the pipe or casing and back up the outside of the pipe or casing through the annular space” to seal the subterranean zones in the formation and support the casing). Even if Chang does not expressly mention cementing, Chang at least suggests compatibility of the disclosed dry polymer particulate system with cementing operations, and Appellant does not assert, much less present persuasive evidence or technical reasoning to suggest, to the contrary. Appellant correctly notes that Chang teaches using its dry polymer particulate system to minimize “fluid loss during completion of a well by forming a filter cake on the surface of the formation” and that “the particulate system bridges the formation face and rehydrate[s] in situ to form a filter-cake.” Appeal Br. 13–14 (citing Chang 1:12–14; 4:36–38). However, Appellant argues that Chang forms a viscous plug in the formation that “is broken for clean-up,” and Chang does not disclose using “sized particulates to delay the set time of a cement downhole.” Id. at 14 (submitting that Appellant’s claims “recite the delay in viscosification of the slurry during the cementing process wherein the slurry forms the cement sheath”). Appeal 2019-004760 Application 14/029,520 18 This line of argument does not apprise of error because, as the Examiner points out (see Ans. 9), claims 1 and 40 do not recite delaying the set time of the cement. Rather, claim 1 recites a method of delaying viscosification of a cement slurry (Appeal Br. 17 (Claims App.)), and claim 40 recites a step of delaying hydration of the cementitious slurry until the slurry is placed into the targeted location or reaches a downhole temperature of 500oF or higher.4 Moreover, and perhaps more importantly, both Reddy and Chang disclose delaying the viscosification of the product until it has reached a desired depth within the wellbore, where it may harden/thicken and plug the zone. Reddy, Abstract; id. ¶¶ 5, 36, 37, 42, 45; Chang 14:22– 24, 65–67; id. 23:48–51; id. 24:6–8. In this sense, the objectives of both Reddy and Chang are the same. Appellant’s argument that, at best, the combination of Reddy and Chang would suggest use of Chang’s HEC for reaction with the organic carbonate to produce the MBA, but not the use of Chang’s HEC itself in Reddy’s cementitious slurry (Reply Br. 14) is not correct. Chang discusses the disadvantages of conventional fluid loss additives containing carbonates (Chang 2:13–50), as well as the cost and complexity of using modified HEC 4 The Examiner relies on DeBruijn as “evidence that it is well-known in the art that temperatures on the order of 500-600oF are encountered downhole” and determines that, thus, it would have been obvious to modify Reddy to form a mass to plug the zone at such elevated temperatures. Final Act. 5 (italics omitted); see Reddy ¶ 45 (disclosing that “the MBA may form a mass that plugs the zone at elevated temperatures, such as those found at higher depths with a wellbore”). “Appellant does not dispute the existence of such downhole temperatures,” nor does Appellant specifically dispute the Examiner’s determination that it would have been obvious to modify Reddy to form a mass to plug a zone at such elevated temperatures. Appeal Br. 14 n.1. Appeal 2019-004760 Application 14/029,520 19 (id. 3:10–4:25). Thus, Chang teaches that it is desirable to use “unmodified HEC” to avoid such cost and complexity. Id. 4:17–25. Along these same lines, Chang teaches that an advantage of the disclosed dry particulate system (i.e., Chang’s HEC) “is that the material behaves as a solid fluid loss control material, such as the often used carbonate pill, but the particles form a tighter network on the face of the rock once they start to hydrate and expand,” and, further, “[t]here is no solid invasion and permanent formation damage like that usually associated with calcium carbonate pills.” Id. 4:58– 65; see also id. 14:24–28 (cited by the Examiner (Final Act. 8, 10) for this teaching). Further, Chang teaches that “[t]he fine particles can be added to a blender tank on location” and “do not hydrate and thicken the water immediately, hence low friction pressure is observed while pumping,” suggesting that Chang’s dry particulate HEC would be suitable for Reddy’s cementitious slurry. Chang 4:56–59; see Reddy ¶ 3 (discussing an interest in developing wellbore cement slurries that increase in viscosity only after passing deeper into the wellbore to avoid the need for high pump pressures and/or low pump rates), ¶ 11 (Reddy disclosing “a pumpable cementitious slurry”). We, therefore discern no error in the Examiner’s determination that the combined teachings of Reddy and Chang render obvious a method comprising introducing a cementitious slurry including cement and Chang’s HEC into a wellbore and delaying hydration and viscosification of the slurry until it reaches a targeted location, and cementing a pipe or casing in the wellbore with the cementitious slurry to form a cement sheath. For the above reasons, Appellant does not apprise us of error in the rejection of claim 1 as unpatentable over Reddy and Chang, or the rejection of claim 40 as unpatentable over Reddy, DeBruijn, and Chang. Appeal 2019-004760 Application 14/029,520 20 Accordingly, we sustain the rejection of claim 1, as well as claims 2, 4, 24, 26, and 31, which depend from claim 1 and for which Appellant does not present any separate arguments (Appeal Br. 12–14), as unpatentable over Reddy and Chang. We also sustain the rejection of claim 40, as well as claim 41, which depends from claim 405 and for which Appellant does not present any separate arguments (id.), as unpatentable over Reddy, DeBruijn, and Chang. Rejections VI and VII—Reddy/Chang/Creel and Reddy/Creel Claim 3 depends from claim 1, and further recites that “the hydratable polymeric viscosifying agent is selected from the group consisting of a polyvinyl alcohol or an ammonium or alkali metal salt of an acrylamidomethylpropanesulfonic acid and mixtures thereof.” Appeal Br. 17 (Claims App.). Claim 46 depends from claim 38, via claim 43, and further recites that “the hydratable polymeric viscosifying agent is an ammonium or alkali metal salt of an acrylamidomethylpropanesulfonic acid.” Id. at 20. The Examiner relies on Creel for teaching acrylamidomethylpropanesulfonic acid (hereinafter AMPS) sized as dry particles of 2 mm (10 mesh) as a swelling agent that hydrates downhole to produce high viscosity. See Final Act. 12, 16 (citing Creel ¶¶ 16–18, 36). The Examiner determines it would have been obvious to modify Reddy to include AMPS sized as dry particles of 2 mm (10 mesh) as taught by Creel 5 The Claims Appendix (Appeal Br. 19) contains an error in reproducing claim 41. See Amendment filed Feb. 11, 2019 (presenting claim 41 depending from claim 40); Advisory Act. dated Feb. 26, 2019 (entering the Amendment). Appeal 2019-004760 Application 14/029,520 21 as the hydratable viscosifying agent “in order to ‘form a mass’ or ‘barrier’ that ‘plugs the zone’ and ‘prevents fluids in that subterranean formation from migrating into other subterranean formations.’” Id. at 12, 16. According to the Examiner, “the modification is obvious as no more than the use of familiar elements (swellable polymers of ~10 mesh size as in Chang/Creel and Reddy) according to known techniques (cementing as in Reddy) in a manner that achieves predictable results (cementing with plugging of voids to reduce fluid loss).” Id. at 12–13 (citing KSR, 550 U.S. at 415–421); see id. at 16–17. Appellant argues that, although Creel discloses using AMPS as a swellable polymer, Creel does not teach using “AMPS in a cementitious slurry for forming a cement sheath.” Appeal Br. 15. Appellant further elaborates that paragraph 36 of Creel, cited by the Examiner, references neither a slurry containing the swellable polymer nor pumping a slurry containing the polymer into a wellbore, but instead places the swellable polymer in a closed container and then releases the swelling agent from the container to isolate the formation. Id.; see also Reply Br. 15 (asserting that Creel’s “swellable polymer is not used in admixture with a cement” and suggesting that a person having ordinary skill in the art would not have a reasonable expectation of success in making the combination). The Examiner responds by dismissing Appellant’s arguments as attacking the references individually. Ans. 9; see In re Merck & Co., 800 F.2d 1091, 1097 (Fed. Cir. 1986) (citing In re Keller, 642 F.2d 413, 425 (CCPA 1981)) (stating, “Non-obviousness cannot be established by attacking references individually where the rejection is based upon the Appeal 2019-004760 Application 14/029,520 22 teachings of a combination of references.”). The Examiner explains that “Reddy provides the cementing, not Creel.” Ans. 10. Here, Appellant’s argument amounts to more than merely an attack on Creel individually. Creel teaches that Creel’s disclosed swelling agent (e.g., AMPS) may be used in primary cementing (which is usually performed by pumping a cement slurry down through a string pipe and into the annulus to allow the cement slurry to set into a cement column). Creel ¶¶ 5, 36. However, Creel does not teach including the swelling agent in the cement slurry and introducing the cementitious slurry into the wellbore. Rather, Creel teaches placing the swelling agent into a container, closing the container, placing the container into the wellbore, and releasing the swelling agent from the container at the position of interest, where the swelling agent is allowed to set such that it isolates the subterranean formation from a different portion of the wellbore. Id. ¶ 36. Further, Creel teaches that in embodiments in which the swelling agent is closed within a container, the swelling agent is placed in the wellbore by dry transport, which means it is not exposed to reactive mediums such as water. Id. ¶ 13. The container is sufficiently closed to prevent exposure of the swelling agent to fluids in the wellbore, which might cause the swelling agent to swell before such swelling is desired. Id. ¶ 32. A person having ordinary skill in the art, having read the teachings of Creel, would not have a reasonable expectation of success in including Creel’s swelling agent in a cementitious slurry and then introducing the cementitious slurry into the wellbore. Rather, Creel’s teachings imply that Creel’s swelling agent, if exposed to reactive media, such as water or other ingredients in the cementitious slurry, might expand prematurely, prior to Appeal 2019-004760 Application 14/029,520 23 arriving at the desired location in the wellbore. See Reddy ¶ 34 (disclosing that, in addition to the MBA, the cementing composition comprises cementitious material, water, and optional additives). Thus, a person having ordinary skill in the art would not have been prompted to include Creel’s swelling agent in Reddy’s cementitious slurry in Reddy’s method. Accordingly, we do not sustain the rejection of claim 3 as unpatentable over Reddy, Chang, and Creel, or the rejection of claim 46 as unpatentable over Reddy and Creel. CONCLUSION In summary: Claims Rejected 35 U.S.C. § Reference(s)/Basis Affirmed Reversed 43, 45, 46 112(b) 43, 45, 46 38, 42, 47 102(a)(1) Reddy 38, 42, 47 33, 34, 43– 45 103 Reddy 33, 34, 43– 45 1, 2, 4, 24, 26, 31 103 Reddy, Chang 1, 2, 4, 24, 26, 31 40, 41 103 Reddy, DeBruijn, Chang 40, 41 3 103 Reddy, Chang, Creel 3 46 103 Reddy, Creel 46 Overall Outcome 1, 2, 4, 24, 26, 31, 40, 41 3, 33, 34, 38, 42–47 TIME PERIOD FOR RESPONSE No time period for taking any subsequent action in connection with this appeal may be extended under 37 C.F.R. § 1.136(a). See 37 C.F.R. § 1.136(a)(1)(iv). Appeal 2019-004760 Application 14/029,520 24 AFFIRMED IN PART Copy with citationCopy as parenthetical citation