DETAILED ACTION
Notice of Pre-AIA or AIA Status
The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Status
Claims 1, 3, 8, 14, and 15 were amended and claims 2 and 17 were canceled in the response filed 12/2/2025. Claims 1, 3-16, and 18-20 are currently pending and under examination.
Drawings
The drawings were received on 12/2/2025. These drawings are acceptable. Therefore, the objection to the drawings on p. 2-3 of the OA dated 7/2/2025 is withdrawn.
Withdrawn Claim Rejections - 35 USC § 112
The Applicant’s amendments are persuasive to overcome the 35 USC 112(b) and 35 USC 112(d) rejections of record on p. 4-5 of the OA dated 7/2/2025. Therefore, the rejections are withdrawn.
Maintained Claim Rejections - 35 USC § 103
Claims 1 and 14 were amended to recite a molar ratio of the carbonate or bicarbonate or combination thereof to the AES in the reaction mixture is equal to or greater than 0.1 and less than 1.0, previously in claims 8 and 15. Claim 17 was canceled and its limitations incorporated into claim 14, which necessitated consolidating the final two 35 USC 103 rejections into one. The rejection of record is on p. 5-16 of the OA dated 7/2/2025 and is maintained.
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1 and 3-12 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hu (US 2015/0183731, published on 7/2/2015, of record) as evidenced by Carbon Dioxide (“5.5 Dissolved Gases: Carbon Dioxide, pH, and Ocean Acidification”, downloaded from https://rwu.pressbooks.pub/webboceanography/chapter/5-5-dissolved-gases-carbon-dioxide-ph-and-ocean-acidification/ on 6/25/2025, of record) and Climate Change (“Climate change: atmospheric carbon dioxide”, downloaded from https://www.climate.gov/news-features/understanding-climate/climate-change-atmospheric-carbon-dioxide on p=6/25/2025, of record).
Applicant Claims
A process for producing taurine comprising:
mixing aminoethanol sulfate ester (AES) with a carbonate or bicarbonate, or combination thereof, thus producing a reaction mixture; and
heating the reaction mixture in the presence of a sulfite or a bisulfite, or combination thereof, such that taurine is formed;
wherein a molar ratio of the carbonate or bicarbonate, or combination thereof to the AES in the reaction mixture is equal to or greater than 0.1 and less than 1.0.
Determining the Scope and Content of the Prior Art (MPEP §2141.01)
Hu discloses a cyclic process for the production of taurine from monoethanolamine (MEA). See abstract. Hu teaches that the process follows the following Scheme in [0008]:
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. In the first step (1) monoethanolamine (MEA) is treated with sulfuric acid (H2SO4) to produce 2-aminoethyl hydrogen sulfate ester (AES). In the second step (2), AES is reacted with a sulfite (M2SO3) to produce taurine and a sulfate (M2SO4) in a sulfonation step. Both reactions are carried out under aqueous conditions. See examples.
Hu further teaches that hydrolysis is a competing mechanism in the second step (2):
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. See [0027]. Hu teaches that one of the options to mitigate the undesirable hydrolysis reaction is to control the pH of the sulfonation by continuously dosing the reaction solution with a base or employing a buffering system. Hu teaches that the bases include sodium and potassium hydroxide (claims 3-5), ammonium hydroxide (claims 3 and 4) and ammonium carbonate (claim 1). See [0030-0032]. Hu also teaches that the sulfonation reaction requires heat and that the reaction temperature falls within the range of 90 to 150°C. See [0026]. In the examples, Hu further teaches that the base is present before heating (claims 7 and 12), and if the base is also continuously dosed, then it is also added during the step of heating (claim 12).
Ascertainment of the Difference Between Scope of the Prior Art and the Claims (MPEP §2141.02-03)
Regarding claims 1, 2, 7, and 12, Hu does not explicitly teach an example wherein the base in the sulfonation step is ammonium carbonate.
Regarding claims 3-6, Hu does not explicitly teach that a mixture of bases is present in the reaction. Nor does Hu comment on the presence of carbon dioxide in the reaction mixture.
Finding of Prima Facie Obviousness Rationale and Motivation (MPEP §2142-2143)
It would have been prima facie obvious to one of ordinary skill in the art to arrive at the instantly claimed process based on the teachings of Hu, as evidenced by Carbon Dioxide and Climate Change, with a reasonable expectation of success before the effective filing date of the claimed invention. A person of ordinary skill in the art would have been motivated to use ammonium carbonate as a base in the sulfonation (step 2) reaction of Hu because Hu explicitly suggests as much, indicating that ammonium carbonate is a preferred base because ammonium cations are already present in the system.
Further regarding claim 1, Hu does not explicitly teach a molar ratio of base to AES. However, Hu teaches that the pH of the reaction is kept in the desired region of 6.0 to 8.0. See [0032] and [0051-0053]. As evidenced by Table 1-2 in [45-46] of the specification as filed, this is the same range as the inventive examples. Therefore, the molar ratio of the base : AES will overlap with that claimed. Further, it would be prima facie obvious to monitor and adjust the concentration of base in the mixture to keep the reaction mixture within the disclosed pH range. Also see MPEP 2144.05.
Further regarding claims 3-6, a person of ordinary skill in the art would have been motivated to use a mixture of ammonium carbonate and another acceptable base, including ammonium hydroxide and sodium hydroxide [0031] because using combinations of known acceptable reactants is prima facie obvious. If a mixture of bases is used in the process of Hu, the process will still predictably produce taurine from AES under pH control. Further regarding claim 6, though Hu is silent regarding the presence of carbon dioxide in the reaction mixture, the reaction conditions of Hu are expected to include carbon dioxide. As evidenced by Carbon Dioxide, carbon dioxide is soluble in water and engages in a reversible reaction to form carbonic acid, which can then be converted to bicarbonate and carbonate depending on the pH of the mixture. See Fig. 5.5.2:
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. Therefore, if the reaction comprises ammonium carbonate, then the mixture comprises dissolved carbon dioxide. Likewise, the skilled artisan would be motivated to bubble CO2 into the reaction mixture in order to generate more carbonate using the well-known acid base reactions above. Alternatively, Hu appears to teach that the reaction mixture is exposed to the atmosphere before heating in the autoclave in the examples. As evidenced by Climate Change (see whole document), carbon dioxide is also present in air/the atmosphere. Thus, carbon dioxide is also being introduced into the reaction mixture from this source.
Regarding claims 8-11, Hu teaches that the molar ratio of the sulfite to AES is from 1:1 to 5:1. See [0026]. This range overlaps with all of those claimed. See MPEP 2144.05.
Claim(s) 13-16 and 18-20 is/are rejected under 35 U.S.C. 103 as being unpatentable over Hu (US 2015/0183731, published on 7/2/2015, of record), as evidenced by Carbon Dioxide and Climate Change as applied to claims 1 and 3-12, and further in view of Yamamoto (US 4657704, published on 4/14/1987, of record) and Plutschack (“The Hitchhiker’s Guide to Flow Chemistry” Chemical Reviews, 2017, p. 111796, of record).
Applicant Claims
Applicant claims the process of claim 1, wherein the heating is carried out in the presence of an inert gas and each of the AES, base, and sulfite are fed to a sulfonation vessel in separate lines and mixed in the vessel.
Applicant claims the process of claim 14 having one of the claimed residence times and the sulfonation vessel of claim 16.
Determining the Scope and Content of the Prior Art (MPEP §2141.01)
The examples of Hu appear to teach that the sulfite and base are mixed first, and then that the AES is added to the combined mixture. The examples also appear to teach that the reaction mixture is exposed to the atmosphere before the sulfonation vessel, an autoclave, is closed and heated. See [0051-0053].
The examples of Hu all appear to be carried out batchwise in a sealed autoclave. See [0045-0055]. Hu also teaches that the reactions are carried out at elevated temperatures and at autogenous to greater than autogenous pressures. See [0026]. Hu teaches that reactions which employ a buffer in place of a base are stirred for a residence time of 24 or 40 hours. See examples 1-3. When a base is added to the system in the cyclic examples 4-8, then the reaction time is decreased to 18 hours.
Yamamoto teaches an analogous process to that of Hu for producing aminoalkylsulfonic acids. Yamamoto teaches that the process comprises reacting a halide of the following formula (wherein X is a halogen):
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with a sulfite to produce an aminoalkylsulfonic acid of the following formula:
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. See abstract and claims. When n is 2 and R1, R2, and R3 are H, the product compound corresponds to taurine. Therefore, Yamamoto teaches a process wherein the sulfate ester leaving group of Hu is replaced by a halogen leaving group. Yamamoto further teaches that the reaction is heated, preferably in stages. See abstract. Yamamoto teaches that the reaction can be carried out under a nitrogen (N2) atmosphere (claims 13, 14, 19, and 20). See examples and claim 1. Yamamoto also appears to teach batch reactions in the examples.
Plutschack is a review of flow chemistry. Plutschack teaches that flow chemistry involves the use of channels or tubing to conduct a reaction in a continuous stream rather than in a flask. Flow equipment provides chemists with unique control over reaction parameters enhancing reactivity or in some cases enabling new reactions. See abstract. Plutschack teaches that commonly reported benefits of continuous processes include better mixing, more efficient heat transfer, and easy-scale up. See first paragraph in introduction section 1 on p. 11797. Plutschack teaches that these benefits lead to reduced energy input, which is particularly attractive from an industrial perspective. See second paragraph in introduction section 1 on p. 11797. Plutschack teaches that flow reactors are suitable for multiphasic reactions and can accommodate many different flow regimes. See section 2.1 on p. 11797-11799. Plutschack also teaches that flow chemistry is a modular technique that can be modified to suit the unique needs of the reaction under consideration. See section 3 on p. 11805 to 11806. Plutschack teaches a simple example of the different zones that can be included in the continuous flow reactor in Fig. 11 on p. 11806:
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. Also see discussion thereof in section 3 on p. 11805-11806. Plutschack teaches that each reactant may have its own line, and that mixing units can be inserted at any point to connect one or more reagent lines to each other before being introduced into the reactor (claims 16).
Plutschack teaches that the systems can contain delivery lines for liquid and gaseous reactants. Plutschack teaches that residence time in the reactors is regulated by precise control over the movement of fluids in the reactor. See sections 3.2 on p. 11806-11807. Plutschack teaches the most common reactor types for flow reaction in Fig. 16 on p. 11809:
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. Also see section 3.4 on p. 11809-11811.
Sections 5 to 6 of Plutschack are dedicated to working examples of flow chemistry processes, which encompass a wide variety of reactions. Thus, Plutschack teaches the broad applicability of flow chemistry.
Ascertainment of the Difference Between Scope of the Prior Art and the Claims (MPEP §2141.02-03)
Hu does not explicitly teach that the heating is carried out in the presence of an inert gas and that each of the AES, base, and sulfite are fed to a sulfonation vessel in separate lines and mixed in the sulfonation vessel. Hu does not explicitly teach a sulfonation apparatus having at least two parts (claim 16). Nor does Hu explicitly teach the residence times of claims 17 and 18.
Finding of Prima Facie Obviousness Rationale and Motivation (MPEP §2142-2143)
It would have been prima facie obvious to combine the teachings of Hu, Yamamoto, and Plutschack to arrive at the instantly claimed process with a reasonable expectation of success before the effective filing date of the claimed invention. A person of ordinary skill would have been motivated to carry out the heating step of Hu under an inert, nitrogen atmosphere, because Yamamoto teaches that this is a known modification for analogous reactions. Therefore, if the reactions of Hu were carried out under a nitrogen atmosphere, the process would still predictably produce taurine. Also see MPEP 2143(I)(B).
A person of ordinary skill in the art would have been further motivated to modify the order of addition of the reactants in the process of Hu to arrive at that claimed because the selection of any order of performing steps and/or mixing ingredients is prima facie obvious. Also see MPEP 2144.04(IV)(C). As Hu teaches that the sulfonation reaction requires heat, the skilled artisan would not expect the order of addition prior to heating to affect the outcome of the reaction.
A person of ordinary skill would have been motivated to carry out the reaction of Hu and Yamamoto continuously because continuous operation is obvious in view of batch processes. See MPEP 2144.04(V)(E). Plutschack is cited to teach modular and adjustable systems for continuous flow operation which would accommodate all of instant steps (a), (b), and (c). Therefore, Plutschack provides support that the combined reaction of Hu and Yamamoto can be predictably facilitated in a continuous fashion. Also see MPEP 2143(B). Further regarding claim 16, as discussed in the preceding section, the selection of any order of performing steps and/or mixing ingredients is prima facie obvious. Also see MPEP 2144.04(IV)(C).
Regarding claim 15, see discussion of claims 8-11 in previous rejection.
Response to Applicant Arguments on p. 7-10 of the response filed 12/2/2025
Applicant argues: “Obviousness cannot be established since Hu does not disclose wherein a molar ratio of the carbonate or bicarbonate, or combination thereof to the aminoethanol sulfate ester (AES) in the reaction mixture is equal to or greater than 0.1 and less than 1.0 as recited in amended claim 1. The Office Action cites paragraphs [0032] and [0051-0053] of Hu for the proposition that Hu teaches that the pH of the reaction is kept in the desired region, and that as evidenced by Table 1- 2 of the applicant's specification, this is the same range.1 However, paragraph [0032] of Hu refers to a buffering system, NOT carbonate or bicarbonate, and paragraphs [0051-053] of Hu do NOT recite any amounts of base added and only refers to adjusting the pH. Accordingly, Hu cannot render amended claim 1 obvious. Claims 2-12 are nonobvious, at the very least, as depending from nonobvious base claims. “
This argument has been fully considered but is not persuasive. As argued in the rejection, Hu teaches that carbonates can be used as bases in the reaction to control the pH of the sulfonation. The bases can be continuously dosed to the sulfonation, used to generate a buffering system, or a combination thereof. See [0030-0032]. Example 8 of Hu in [0051-0053] explicitly teaches using an ammonium sulfate buffer to control the pH level of the sulfonation, and further controlling the pH level through the use of additional amounts of ammonium hydroxide if necessary. Hu does not explicitly teach a molar ratio of base to AES. However, Hu teaches that the pH of the reaction is kept in the desired region of 6.0 to 8.0, by use of a buffer and/or dosing of a base (which would correspond to the instantly claimed carbonate bases). As evidenced by Table 1-2 in [45-46] of the specification as filed, this is the same pH range as the inventive examples and is controlled by the concentration of the carbonate base in the mixture. Hu teaches bases which overlap with those claimed and a preferred pH range which overlaps with that of the inventive examples. Hu and the inventive examples also teach that the concentration of the base in the system directly influences the pH of the system. Therefore, the Office maintains that the skilled artisan could predictably arrive at the instantly claimed molar ratio of base : AES by following the pH guidelines set forth by Hu with a reasonable expectation of success and that molar ratio of the base : AES will overlap with that claimed. Further, it would be prima facie obvious to monitor and adjust the concentration of base in the mixture to keep the reaction mixture within the disclosed pH range. Also see MPEP 2144.05.
Double Patenting
The rejections of record on p. 16-18 of the OA dated 7/2/2025 and reiterated herein.
The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969).
A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b).
The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13.
The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer.
Claims 1, 3-16, and 18-20 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 2, 5-8, 12, 15, 17, 18, 22, 26, 27, and 31-37 of co-pending Application No. 18/002329 (‘329, reference application).
Although the claims at issue are not identical, they are not patentably distinct from each other because claim 1 of ‘329 is a species of the process of instant claim 1-2, which further comprises a step for producing AES from MEA and sulfuric acid. Regarding claims 3-6, see claims 1 and 2 of ‘329 and MPEP 2144.07; regarding claims 7 and 12, see claims 5-7 of ‘329; regarding claims 8-11 and 15, see claim 8 of ‘329; regarding claims 13, 19, and 20, see claims 12 and 15 of ‘329; regarding claims 14, and 16, see claim 26 of ‘329 and MPEP 2144.04(IV)(C). Regarding claims 17-18 though the claims of ‘329 do not explicitly teach or suggest these limitations, they are routinely optimizable variables in continuous processes. See MPEP 2144.05. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
Claims 1, 3-16, and 18-20 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-20 of co-pending Application No. 17/907151 (‘151, reference application), as evidenced by Carbon Dioxide (“5.5 Dissolved Gases: Carbon Dioxide, pH, and Ocean Acidification”, downloaded from https://rwu.pressbooks.pub/webboceanography/chapter/5-5-dissolved-gases-carbon-dioxide-ph-and-ocean-acidification/ on 6/25/2025).
Although the claims at issue are not identical, they are not patentably distinct from each other because claim 1 of ‘151 is an obvious variant of the process of instant claims 1-2, wherein the bicarbonate or carbonate is formed in situ from carbon dioxide and the base of claim 3 of ‘151. See Fig. 5.5.2 in the evidentiary reference. Regarding claims 3-6, see claims 3-5 of ‘151; regarding claims 7 and 12, see claims 6-7 of ‘151; regarding claims 8-11 and 15, see claims 8-11 of ‘151; regarding claims 13, 19, and 20, see claims 13, 14, 19, and 20 of ‘151; regarding claims 14, and 16, see claims 14 and 16 of ‘151 and MPEP 2144.04(IV)(C); regarding claims 17 and 18, see claims 17 and 18 of ‘151.
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented; however, the issue fee was paid in the ‘151 case on 12/26/2025.
The Office acknowledges the Applicant’s request to have the provisional non-statutory double patenting rejections held in abeyance on p. 9 of the response filed 12/2/2025.
Conclusion
THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a).
A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action.
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/AMY C BONAPARTE/Primary Examiner, Art Unit 1692