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 .
DETAILED ACTION
Claims 1-2, 7-8, 11-12, 16-20, 22-23, 33-34, 37-28, 40, 43 and 46 are under examination herein.
The rejection of claims 1-2, 7-8, 16 and 18-20 under 35 U.S.C. 102 as being anticipated by Ludtke is withdrawn in light of the claim amendment requiring the high purity biogas to comprise at least 85% methane.
Priority
This application, filed on 5/10/2024, is a 371 of PCT/US2022/49579 filed on 11/10/2022, which claims benefit of 63/277,960 filed on 11/10/2021. The effective filing date of the current application is November 10, 2021.
Claim Rejections - 35 USC § 103
The following is a quotation of 35 U.S.C. 103 which forms the basis for all obviousness rejections set forth in this Office action:
A patent for a claimed invention may not be obtained, notwithstanding that the claimed invention is not identically disclosed as set forth in section 102, if the differences between the claimed invention and the prior art are such that the claimed invention as a whole would have been obvious before the effective filing date of the claimed invention to a person having ordinary skill in the art to which the claimed invention pertains. Patentability shall not be negated by the manner in which the invention was made.
The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows:
1. Determining the scope and contents of the prior art.
2. Ascertaining the differences between the prior art and the claims at issue.
3. Resolving the level of ordinary skill in the pertinent art.
4. Considering objective evidence present in the application indicating obviousness or nonobviousness.
This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention.
New rejection necessitated by amendment: Claims 1-2, 7-8, 12, 16-18, 20, 22-23, 33-34, 37, 40, 43 and 46 are rejected under 35 U.S.C. 103 as being unpatentable over Ludtke et al. (US2016/0230134A1, published on August 11, 2016; previously cited) in view of Stepany et al. (US 11,168,339 B1, issued on November 9, 2021; previously cited) and Cho et al. (“Biochemical Methane Potential and Solid State Anaerobic Digestion of Korean Food Wastes”, Bioresource Technology, 1995, Vol. 52, pp.245-253).
Regarding claim 1 step a, Ludtke teaches anaerobic fermentation of the heat-treated lignocellulose-containing biomass by means of microorganisms and recovery of the biogas formed (p.3-4, [0037]).
Regarding claim 1 step b, Ludtke teaches anaerobic fermentation in one or more fermenters (i.e. reaction vessel) (p.5, [0053]). Ludtke teaches the formation of biogas is considerably improved especially through adjustment of the sodium content, if desired by introduction of sodium hydroxide solution (p.3, [0033]). Ludtke teaches the enzymatic digestion is at a pH 8-10 (p.5, [0050]).
Regarding claim 1 step c, Ludtke teaches the residence time of the anaerobic fermentation is selected such that a stable microorganism population is established in the fermenter, and with mesophilic or thermophilic operation, a residence time from 10 to 50 days is advantageous; the biogas generated is collected and taken off for further processing (p.6, [0057]). Ludtke teaches the thermal digestion takes place in the aqueous phase at a temperature from 130°C to 200°C (i.e. at least 45°C) (p.9, [0094]).
Ludtke does not identify whether the pH is maintained at an alkaline pH.
However, Stepany teaches effective fermentation conditions may include fermentation temperature to about 70°C and a fermentation pH to about 8.5 (col. 3, lines 48-52).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to maintain the pH in the fermenter of Ludtke at an alkaline pH taught by Stepany, because Stepany teaches effective fermentation conditions may include a fermentation pH of 8.5. One of ordinary skill in the art would have found it beneficial to select an alkaline pH of 8.5 to ensure effective fermentation conditions.
Regarding claim 1 step d, Ludtke teaches the biogas generated is collected and taken off for further processing (p.6, [0057]).
Ludtke does not teach collecting the high purity biogas from the reaction vessel, or wherein the high purity biogas comprises at least 85% methane by volume.
Cho teaches biochemical methane production from anaerobic digestion (title). Cho teaches the methane reactor was inoculated with anaerobic digestion sludge from Taejon sanitary treatment plant (p.246, 2nd column – 3rd paragraph). Cho teaches cumulative methane production reached at least 85% up to 95% methane content (p.248, Fig.3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Ludtke to adjust the composition of solids fermented as taught by Cho to yield biogas containing at least 85 vol% of methane, because Cho teaches adjusting the solid composition increased the methane production and methane content of the biogas produced. Each of Ludtke, Stepany and Cho teach the production of methane containing biogas. One of ordinary skill in the art would reasonably expect that adjusting the input biomass would predictably result in a biogas containing increased methane, because it was known in the art at the time of invention that biogas comprising at least 85% methane could be produced from anaerobic fermentation.
Regarding claim 2, Ludtke teaches a residence time of 10 to 50 days (p.6, [0057]).
Regarding claims 7 and 8, Ludtke teaches a pH of 8-10 (p.6, [0050]).
Regarding claim 12, Ludtke does not teach wherein the high purity biogas comprises at least 95% methane by volume.
Cho teaches biochemical methane production from anaerobic digestion (title). Cho teaches the methane reactor was inoculated with anaerobic digestion sludge from Taejon sanitary treatment plant (p.246, 2nd column – 3rd paragraph). Cho teaches cumulative methane production reached at least 85% up to 95% methane content (p.248, Fig.3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Ludtke to adjust the composition of solids fermented as taught by Cho to yield biogas containing at least 95 vol% of methane, because Cho teaches adjusting the solid composition increased the methane production and methane content of the biogas produced. Each of Ludtke, Stepany and Cho teach the production of methane containing biogas. One of ordinary skill in the art would reasonably expect that adjusting the input biomass would predictably result in a biogas containing increased methane, because it was known in the art at the time of invention that biogas comprising at least 85% methane could be produced from anaerobic fermentation.
Regarding claim 16, Ludtke teaches the formation of biogas is considerably improved especially through adjustment of the sodium content, if desired by introduction of sodium hydroxide solution (p.3, [0033]).
Regarding claim 17, Ludtke teaches lignocellulose-containing biomass includes straw, grasses, wood or other agricultural and forestry wastes (p.3, [0029]).
Ludtke does not teach switchgrass.
However, Stepany teaches a process for converting a lignocellulosic feedstock material into methane (col. 13, lines 36-37). Stepany teaches lignocellulosic feedstock biomass such as agricultural wastes, forest products, grasses, including one or more materials selected from grass straw, corn stover, wheat straw, rice straw, cotton burr, switchgrass, animal manure, municipal garbage, municipal sewage (col. 13, lines 52-60).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to substitute switchgrass taught by Stepany for the lignocellulosic biomass in the method of Ludtke, because Stepany teaches lignocellulosic feedstock can include a variety of cellulosic material including switchgrass. Each of Ludtke and Stepany teach the conversion of lignocellulosic- containing material into methane gas. One of ordinary skill in the art would reasonably expect that substituting one known lignocellulosic feedstock material, i.e. switchgrass, for another lignocellulosic feedstock material would predictably result in the production of methane because it was known in the art at the time of invention that feedstock comprising switchgrass could be fermented to produce methane.
Regarding claim 18, Ludtke teaches in the fermentation process, about 40% of the organic starting mass (i.e. carbohydrate conversion is at least 30%) should be degraded and converted into biogas by the first fermentation process with an average duration of 25 days (p.1, [0010]).
Regarding claim 20, Ludtke teaches that it can be useful to shred the lignocellulose-containing biomass mixed in the suspension, especially if the average substrate particle size is greater than 2 mm, which can for example be achieved with a wet shredding by means of a wet mill or cutting wheels in the pipe transport system or disperser (p.5, [0052]). Ludtke further teaches that the wet shredding can also be performed in several stages, including directly after the mixing, but also after the heat exchanger directly before the anaerobic fermentation (p.5, [0052]).
Regarding claim 22 step a, Ludtke teaches a method and plant for producing biogas from lignocellulose-containing material (title). Ludtke teaches the production of biogas from lignocellulose-containing biomass takes place like the fermentation of liquid manure and sustainable raw materials (SRM) by means of the steps: processing of the lignocellulose-containing biomass; mixing with water; anaerobic fermentation by microorganisms via the intermediate steps hydrolysis, acidogenesis, acetogenesis and methanogenesis (p.1, [0005]). Ludtke further teaches mixing the fiber containing phase with the untreated part of the outflow with the fiber-containing phase (p.9, [0095]).
Regarding claim 22 step b, Ludtke teaches anaerobic fermentation in one or more fermenters (i.e. reaction vessel) (p.5, [0053]). Ludtke teaches residence time of anaerobic fermentation is selected such that a stable microorganism population is established in the fermenter, with mesophilic or thermophilic operation, a residence time of 10 to 50 days is advantageous (p.6, [0057]). Ludtke teaches the formation of biogas is considerably improved especially through adjustment of the sodium content, if desired by introduction of sodium hydroxide solution (p.3, [0033]). Ludtke teaches the biogas generated is collected and taken off for further processing (p.6, [0057]).
Ludtke does not teach wherein the high purity biogas from the reaction vessel comprises at least 85% methane by volume.
Cho teaches biochemical methane production from anaerobic digestion (title). Cho teaches the methane reactor (reaction vessel) was inoculated with anaerobic digestion sludge from Taejon sanitary treatment plant (p.246, 2nd column – 3rd paragraph). Cho teaches cumulative methane production reached at least 85% up to 95% methane content (p.248, Fig.3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Ludtke to adjust the composition of solids fermented as taught by Cho to yield biogas containing at least 85 vol% of methane, because Cho teaches adjusting the solid composition increased the methane production and methane content of the biogas produced. Each of Ludtke, Stepany and Cho teach the production of methane containing biogas. One of ordinary skill in the art would reasonably expect that adjusting the input biomass would predictably result in a biogas containing increased methane, because it was known in the art at the time of invention that biogas comprising at least 85% methane could be produced from anaerobic fermentation.
Regarding claim 22 step c, Ludtke teaches the biogas generated is collected and taken off for further processing (p.6, [0057]).
Ludtke does not teach collecting the high purity biogas from the reaction vessel.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Ludtke to adjust the composition of solids fermented as taught by Cho to yield biogas containing at least 85 vol% of methane collected from the fermenter, because Cho teaches adjusting the solid composition increased the methane production and methane content of the biogas produced. Each of Ludtke, Stepany and Cho teach the production of methane containing biogas. One of ordinary skill in the art would reasonably expect that adjusting the input biomass would predictably result in a biogas containing increased methane directly from the fermenter, because it was known in the art at the time of invention that biogas comprising at least 85% methane could be produced from anaerobic fermentation.
Regarding claim 23, Ludtke further teaches in circa 40% of the organic starting mass should be degraded (i.e. at least 34% carbohydrate conversion) and converted into biogas by the first fermentation process with an average duration of 25 days (p.1, [0010]).
Regarding claims 33-34, Ludtke teaches a pH of 8-10 (i.e. alkaline pH) (p.6, [0050]).
Regarding claim 37, Ludtke further teaches thermal digestion advantageously takes place at 130°C to 200°C (i.e. at least 45°C) (p.6, [0060]; claim 4).
Regarding claim 40, Ludtke teaches the formation of biogas is considerably improved especially through adjustment of the sodium content, if desired by introduction of sodium hydroxide solution (p.3, [0033]).
Regarding claim 43 step a, Ludtke teaches anaerobic fermentation of the heat-treated lignocellulose-containing biomass by means of microorganisms and recovery of the biogas formed (p.3-4, [0037]). Ludtke further teaches mixing the fiber containing phase with the untreated part of the outflow with the fiber-containing phase (p.9, [0095]).
Regarding claim 43 step b, Ludtke teaches anaerobic fermentation in one or more fermenters (i.e. reaction vessel) (p.5, [0053]). Ludtke teaches residence time of anaerobic fermentation is selected such that a stable microorganism population is established in the fermenter, with mesophilic or thermophilic operation, a residence time of 10 to 50 days is advantageous (p.6, [0057]). Ludtke further teaches in circa 40% of the organic starting mass should be degraded and converted into biogas by the first fermentation process with an average duration of 25 days (p.1, [0010]).
Ludtke does not teach at least 2.0% daily carbohydrate conversion of the lignocellulosic biomass to produce a high purity biogas comprising at least 85% methane by volume.
Cho teaches biochemical methane production from anaerobic digestion (title). Cho teaches the methane reactor was inoculated with anaerobic digestion sludge from Taejon sanitary treatment plant (p.246, 2nd column – 3rd paragraph). Cho teaches cumulative methane production reached at least 85% up to 95% methane content (p.248, Fig.3).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Ludtke to adjust the composition of solids fermented as taught by Cho to yield biogas containing at least 85 vol% of methane, because Cho teaches adjusting the solid composition increased the methane production and methane content of the biogas produced. Each of Ludtke, Stepany and Cho teach the production of methane containing biogas. One of ordinary skill in the art would reasonably expect that adjusting the input biomass would predictably result in a biogas containing increased methane, because it was known in the art at the time of invention that biogas comprising at least 85% methane could be produced from anaerobic fermentation.
The instant specification identifies that the claimed method can produce a high purity biogas of at least 85% methane by volume at a daily carbohydrate conversion of at least 2.0% per day as calculated using quantitative saccharification (instant specification p.12, lines 15-23). The method taught by Ludtke is the same method described in the specification. Thus, one of ordinary skill in the art would reasonably expect that producing a high purity gas of at least 85% methane would predictably result in a daily carbohydrate conversion of lignocellulosic material of at least 2.0%, because Ludtke reaches a carbohydrate conversion of at least 40% in an average of 25 days.
Regarding claim 43 step c, Ludtke teaches the biogas generated is collected and taken off for further processing (p.6, [0057]).
Ludtke does not teach collecting the high purity biogas from the reaction vessel.
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of Ludtke to adjust the composition of solids fermented as taught by Cho to yield biogas containing at least 85 vol% of methane collected from the fermenter, because Cho teaches adjusting the solid composition increased the methane production and methane content of the biogas produced. Each of Ludtke, Stepany and Cho teach the production of methane containing biogas. One of ordinary skill in the art would reasonably expect that adjusting the input biomass would predictably result in a biogas containing increased methane directly from the fermenter, because it was known in the art at the time of invention that biogas comprising at least 85% methane could be produced from anaerobic fermentation.
Regarding claim 46, Ludtke teaches mixing the fiber containing phase with the untreated part of the outflow with the fiber-containing phase (p.9, [0095]).
New rejection necessitated by amendment: Claims 19 and 38 are rejected under 35 U.S.C. 103 as being unpatentable over Ludtke et al. (US2016/0230134A1, published on August 11, 2016; previously cited) in view of Stepany et al. (US 11,168,339 B1, issued on November 9, 2021; previously cited) and Cho et al. (“Biochemical Methane Potential and Solid State Anaerobic Digestion of Korean Food Wastes”, Bioresource Technology, 1995, Vol. 52, pp.245-253) as applied to claims 1 and 22 above, and further in view of Nguyen et al. (“Application of rumen and anaerobic sludge microbes for bio harvesting from lignocellulosic biomass”, Chemosphere, 2019, Vol. 228, pp.702-708; previously cited).
The teachings of Ludtke et al., Stepany et al. and Cho et al. are discussed above.
Regarding claims 19 and 38, Ludtke teaches the outflow from the second fermenter can be separated by a solid-liquid separation into a liquid and a solids-containing phase (p.6, [0064]).
Ludtke and Stepany do not teach wherein incubation of the feedstock mixture produces a digestate comprising volatile fatty acids and wherein the volatile fatty acid net production is at least 50 mg/ VFA/g lignocellulosic biomass fed.
Cho teaches food waste contains high soluble organics, which are converted rapidly to volatile fatty acids (VFAs) at an early stage of digestion p.245, 2nd column 1st paragraph).
Cho does not teach wherein the volatile fatty acid net production is at least 50 mg/ VFA/g lignocellulosic biomass fed.
However, Nguyen teaches the production of biogas, volatile fatty acids (VFAs) and other soluble organic from lignocellulosic biomass by two microbial communities (abstract). Nguyen teaches VFA production from lignocellulosic biomass is the building block chemical for biofuel (abstract). Nguyen teaches an average 100 mg VFA per g of lignocellulosic biomass was produced after two days of inoculation with rumen fluid (i.e. at least 50 mg VFA / g lignocellulosic biomass) (p.705, 1st column – 2.1. Volatile fatty acid production).
It would have been obvious to one of ordinary skill in the art before the effective
filing date of the claimed invention to replace the microorganism community taught by
Ludtke with rumen fluid microorganism community taught by Nguyen in the method of
Ludtke and Stepany to obtain an average 100 mg VFA / g lignocellulosic biomass.
Each of Ludtke, Stepany and Nguyen teach fermentation of biomass using microbial
communities. One of ordinary skill in the art would reasonably expect that fermenting
lignocellulosic biomass with a microbial community would predictably result in the
production of volatile fatty acids as a desired level, because it was known in the art at
the time of invention that fermenting lignocellulosic biomass material resulted in the
production of volatile fatty acids and biogas.
Modified rejection necessitated by amendment: Claim 11 is rejected under 35 U.S.C. 103 as being unpatentable over Ludtke et al. (US2016/0230134A1, published on August 11, 2016; previously cited) in view of Stepany et al. (US 11,168,339 B1, issued on November 9, 2021; previously cited) and Cho et al. (“Biochemical Methane Potential and Solid State Anaerobic Digestion of Korean Food Wastes”, Bioresource Technology, 1995, Vol. 52, pp.245-253) as applied to claim 1 above, and further in view of Cornelius Van Haandel et al. (WO 2012/153189 A2, published on November 15, 2012; previously cited). As the original WO 2012/153189 A2 document is in Portuguese, an English translation is relied upon for support.
The teachings of Ludtke et al., Stepany et al. and Cho et al. are discussed above.
Regarding claim 11, Ludtke teaches that microorganisms which carry out hydrolysis, acidogenesis, acetogenesis and methanogenesis are used (p.6, [0057]).
Ludtke and Stepany do not disclose the origin of the microorganisms.
Cho teaches the methane reactor was inoculated with anaerobic digestion sludge from Taejon sanitary treatment plant (p.246, 2nd column – 3rd paragraph).
However, Cornelius Van Haandel teaches a process and system for producing biogas from anaerobic digestion of plant biomass in solid phase (English Translation - title). Cornelius Van Haandel teaches the biogas generated from anaerobic digestion is composed of methane, carbon dioxide, among others (English translation p.2, Background – paragraph 7). Cornelius Van Haandel teaches anaerobic bacteria can be selected from anaerobic sludges from wastewater treatment plants or solid domestic or industrial waste (English translation p.3, 3rd paragraph from bottom of page).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to substitute the bacteria (mixed microbial community) from anaerobic sludge from wastewater treatment plants as taught by Cornelius Van Haandel for the microorganisms in the method of Ludtke and Stepany, because Cornelius Van Haandel teaches such sources as containing anaerobic microorganisms that can be used to produce methane from plant biomass. Each of Ludtke, Stepany, Cho and Cornelius Van Haandel teach the use of microorganisms to produce methane biogas from biomass. One of ordinary skill in the art would reasonably expect that substitution of one known source of anaerobic microorganisms for another would predictably result in the production of methane from digesting plant biomass.
Response to Arguments
Applicant argues Ludtke’s pH reference of 2-10 does not pertain to the pH during anaerobic fermentation and describes operating conditions used during aerobic biological pretreatment for enzymatic digestion of moistened straw, and one of ordinary skill in the art would recognize that Ludtke does not incubate the feedstock mixture anaerobically in the reaction vessel for a retention time at a thermophilic temperature of at least 45°C while maintaining the alkaline pH as presently claimed (See Remarks dated 6/24/2026 p.10, 2nd paragraph). Applicant argues that claims 1, 22 and 43 have each been amended to recite that the feedstock mixture is incubated/digested in a reaction vessel to form high purity biogas comprising at least 85% methane by volume, whereas Stepany uses a subsequent biogas upgrading unit to enrich biogas and remove unwanted components (see Remarks dated 6/24/2026, p.10 last paragraph – p.11 top paragraph).
Applicant explains that conventional anaerobic digestion generates a biogas having a concentration of methane ranging from 50%-75% by volume, with the remainder being almost entirely carbon dioxide, which needs to be processed by a gas separation/upgrading unit to reach the high methane purity required to be used for renewably natural gas (RNG) to be injected into commercial pipeline infrastructure, and requires substantial cost and greatly increases the greenhouse gas footprint of the resulting RNG (See Remarks dated 6/24/2026, p.11, 1st full paragraph). Applicant further expresses that the claimed methods dramatically reduce the separation energy requirements and costs, and in some cases generate a biogas of sufficient purity such that it meets pipeline specifications without further processing, and similarly the operation of anaerobic digestion at an alkaline pH avoids the need to pretreat the lignocellulosic biomass to achieve high conversion of its carbohydrates into bioproducts including high yields of volatile fatty acids and high purity methane (See Remarks dated 6/24/2026, p.11 1st full paragraph).
Applicant's arguments filed June 24, 2026 have been fully considered but they are not persuasive. In response to applicant's arguments against the references individually, one cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. See In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986).
As discussed in the rejection above, Ludtke teaches anaerobic fermentation in a fermenter (i.e. a reaction vessel) using a microorganism population, with mesophilic or thermophilic operation, and the biogas generated is collected and taken off. Stepany teaches effective fermentation conditions may include fermentation temperature to about 70°C and a fermentation pH to about 8.5. Cho teaches producing high purity methane biogas using solid state anaerobic digestion. One of ordinary skill in the art would have found it obvious to combine the teachings of Ludtke, Stepany and Cho to obtain a high purity biogas comprising at least 85% methane for the reasons discussed above.
Double Patenting
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.
Modified rejection necessitated by amendment: Claims 1, 7-8, 12, and 18-20 are provisionally rejected on the grounds of nonstatutory double patenting as being unpatentable over claims 21, 23, 29-30, 35, 37 and 40 of copending Application No. 18/709,342 (reference application). Although the claims at issue are not identical, they are not patentably distinct from each other because the instant claims are anticipated by the reference claims.
Claim 21 of ‘342 is drawn to a method for forming a high purity biogas and a residual biogas from a lignocellulosic biomass, the method comprising the steps of:
a. inoculating a feedstock mixture comprising the lignocellulosic biomass with a mixed microbial community;
b. contacting the feedstock mixture with effective amount of a first pH adjusting agent to increase a pH of the feedstock mixture to an alkaline pH;
c. incubating the feedstock mixture anaerobically for a first retention time at a thermophilic temperature of at least 45°C thereby forming a first biogas and a first digestate;
d. collecting the first biogas;
e. contacting the first digestate with effective amount of a second pH adjusting agent to decrease a pH of the first digestate to a substantially neutral pH;
f. incubating the first digestate anaerobically for a second retention time thereby forming a second biogas; and
g. collecting the second biogas (relevant to instant claim 1).
Claim 23 of ‘342 is drawn to the method of claim 21, wherein the first biogas comprises 85% methane by volume (relevant to instant claims 1 and 12).
Claim 29 of ‘342 is drawn to the method of claim 21, wherein the first digestate comprises volatile fatty acids and wherein the volatile fatty acid net production is at least 50 mg VFA/g lignocellulosic biomass fed (relevant to instant claim 19).
Claim 30 of ‘342 is drawn to the method of claim 21, wherein the total carbohydrate conversion of the lignocellulosic biomass is greater than 30% (relevant to instant claim 18).
Claim 35 of ‘342 is drawn to the method of claim 21, wherein the alkaline pH is from 8.0 to 10.0 (relevant to instant claims 7 and 8).
Claim 37 of ‘342 is drawn to the method of claim 21, further comprising milling the feedstock mixture during the first retention time (relevant to instant claim 20).
Claim 40 of ‘342 is drawn to a method for forming a volatile fatty acid (VFA) from a lignocellulosic biomass, the method comprising:
a. inoculating a feedstock mixture comprising the lignocellulosic biomass with a mixed microbial community;
b. contacting the feedstock mixture with effective amount of a pH adjusting agent to increase a pH of the feedstock mixture to an alkaline pH; and
c. incubating the feedstock mixture anaerobically for a retention time at a thermophilic temperature of at least 45°C thereby forming a digestate comprising a VFA (relevant to instant claim 1).
This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented.
New rejection necessitated by amendment: Claims 22-23, 33-34, 37-38, 40, 43 and 46 are provisionally rejected on the grounds of nonstatutory double patenting as being unpatentable over claims 21, 23, 29-30, 35, 37 and 40 of copending Application No. 18/709,342 in view of Ludtke et al. (US2016/0230134A1, published on August 11, 2016; previously cited).
Claim 21 of ‘342 is drawn to a method for forming a high purity biogas and a residual biogas from a lignocellulosic biomass, the method comprising the steps of:
a. inoculating a feedstock mixture comprising the lignocellulosic biomass with a mixed microbial community;
b. contacting the feedstock mixture with effective amount of a first pH adjusting agent to increase a pH of the feedstock mixture to an alkaline pH;
c. incubating the feedstock mixture anaerobically for a first retention time at a thermophilic temperature of at least 45°C thereby forming a first biogas and a first digestate;
d. collecting the first biogas;
e. contacting the first digestate with effective amount of a second pH adjusting agent to decrease a pH of the first digestate to a substantially neutral pH;
f. incubating the first digestate anaerobically for a second retention time thereby forming a second biogas; and
g. collecting the second biogas (relevant to instant claims 22, 37, 40, 43 and 46).
Claim 23 of ‘342 is drawn to the method of claim 21, wherein the first biogas comprises 85% methane by volume (relevant to instant claims 22 and 43).
Claim 29 of ‘342 is drawn to the method of claim 21, wherein the first digestate comprises volatile fatty acids and wherein the volatile fatty acid net production is at least 50 mg VFA/g lignocellulosic biomass fed (relevant to instant claim 38).
Claim 30 of ‘342 is drawn to the method of claim 21, wherein the total carbohydrate conversion of the lignocellulosic biomass is greater than 30% (relevant to instant claims 22 and 23).
Claim 35 of ‘342 is drawn to the method of claim 21, wherein the alkaline pH is from 8.0 to 10.0 (relevant to instant claims 33 and 34).
Claim 40 of ‘342 is drawn to a method for forming a volatile fatty acid (VFA) from a lignocellulosic biomass, the method comprising:
a. inoculating a feedstock mixture comprising the lignocellulosic biomass with a mixed microbial community;
b. contacting the feedstock mixture with effective amount of a pH adjusting agent to increase a pH of the feedstock mixture to an alkaline pH; and
c. incubating the feedstock mixture anaerobically for a retention time at a thermophilic temperature of at least 45°C thereby forming a digestate comprising a VFA (relevant to instant claims 22, 37, 40 and 43).
Copending claims ‘342 do not recite unpretreated lignocellulosic biomass.
However, Ludtke teaches mixing the fiber containing phase with the untreated part of the outflow with the fiber-containing phase (p.9, [0095]).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the method of copending claims ‘342 to use untreated lignocellulosic biomass taught by Ludtke. Ludtke teaches the production of methane biogas using anaerobic fermentation. One of ordinary skill in the art would reasonably expect that replacing treated lignocellulosic biomass with unpretreated lignocellulosic biomass would predictably result in the production of a biogas comprising methane, because it was known in the art that anaerobic fermentation of unpretreated lignocellulosic biomass produced biogas comprising methane.
This is a provisional nonstatutory double patenting rejection.
Response to Arguments
Applicant requests that the double patenting rejection be held in abeyance until allowable subject matter is determined, and at that time will consider filing a terminal disclaimer if necessary (See Remarks dated 6/24/2026, p.12 – Double patenting rejection).
Applicant’s request filed June 24, 2026 to hold the provisional nonstatutory double patenting rejection in abeyance until notification of allowable subject matter is improper.
The rejection cannot be held in abeyance as per MPEP §804 I. B. 1.: As filing a terminal disclaimer, or filing a showing that the claims subject to the rejection are patentably distinct from the reference application’s claims, is necessary for further consideration of the rejection of the claims, such a filing should not be held in abeyance. Only compliance with objections or requirements as to form not necessary for further consideration of the claims may be held in abeyance until allowable subject matter is indicated.
Conclusion
Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to DEEPA MISHRA whose telephone number is (571) 272-6464. The examiner can normally be reached Monday - Friday 8:30am - 1:30pm EST.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Louise W. Humphrey can be reached at (571) 272-5543. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/LOUISE W HUMPHREY/Supervisory Patent Examiner, Art Unit 1657
/DEEPA MISHRA/Examiner, Art Unit 1657
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