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 .
Response to Amendment
In response to the amendment received on 05/28/2026:
claims 1-10 are currently pending;
the 112(b) rejection to claims 1-9 are withdrawn in light of the amendment to the claims;
the allowable subject matter in claims 3-4 are maintained for at least the reasons as set forth herein; and
all prior art grounds of rejection are maintained for at least the reasons as set forth herein.
Claim Rejections - 35 USC § 103
In the event the determination of the status of the application as subject to AIA 35 U.S.C. 102 and 103 (or as subject to pre-AIA 35 U.S.C. 102 and 103) is incorrect, any correction of the statutory basis (i.e., changing from AIA to pre-AIA ) for the rejection will not be considered a new ground of rejection if the prior art relied upon, and the rationale supporting the rejection, would be the same under either status.
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.
Claims 1-2 and 5-10 are rejected under 35 U.S.C. 103 as being unpatentable over Gupta ("Carbon sequestration in cementitious matrix containing pyrogenic carbon from waste biomass: A comparison of external and internal carbonation approach", Journal of Building Engineering, 2021) (“Gupta” hereinafter).
Regarding claim 1, Gupta teaches a cementitious composition (see Gupta at page 4, left column, section 2.3 teaching four mixes are investigated in this disclosure including… cement paste). Cement paste is taken to meet the claimed “cementitious composition”, comprising
at least 5% in weight of the cementitious composition of carbonated biochar (Gupta teaches this limitation as outlined below).
Gupta teaches cement paste with 2.5% CO2-saturated biochar (SatBC-CP)… the dosage of biochar is selected based on the author’s previous findings – addition of 2– 5% wood biochar by weight of cement was found to improve hydration and compressive strength of mortar by 10-20% compared to control… while 2% wood-based biochar improved strength of cement mortar by 9% at 28-day age, addition of 5% biochar did not have significant effect on strength (see Gupta at page 4, left column, section 2.3)… the ground biochar… is saturated with CO2… the saturation point is reached when the pores of biochar are filled with CO2 (see Gupta at page 4, left column, section 2.2, paragraph 1). One of ordinary skill in the art would appreciate that 5wt% biochar did not have significant effect on strength of cement mortar compared to the 2% by weight of cement biochar, but still improved strength of cement mortar by 9% at 28-day age. CO2-saturated biochar (SatBC-CP) is taken to meet the claimed “carbonated biochar” based on specification at page 5 lines 23-25 disclosing carbonated biochar is disclosed as any biochar which, after being brought into contact with a gas flow enriched flow in CO2, retains part of it in its porous structure, and therefore contains adsorbed CO2.
Gupta further teaches this disclosure also demonstrated a novel strategy of internal carbonation using biochar as storage site for carbon dioxide pre-deployment in cement… this strategy result in better hydration and enhanced strength than control, while reducing associated CO2–eq emission… applying this technique, spent CO2–saturated at the end of service life from other industrial streams can be valorized as cementitious admixture (see Gupta at page 18, right column, paragraph 1). Gupta also teaches the internal carbonation strategy, using CO2–saturated biochar, can enhance early (7 days) compressive strength by 25–30% and 12–15% compared to uncarbonated control and SF-CP… SatBC-CP offers similar strength as that of carbonated control and SF-CP after 28 days, indicating this type of biochar-cement can satisfy the designed strength grade for concrete constructions (see Gupta at page 19, left column, last bullet). 5wt% CO2–saturated biochar in the cement paste is taken to meet the claimed “at least 5% of carbonated biochar”.
Additionally, MPEP states that "[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation", and “the normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages” (see MPEP § 2144.05.II.A).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have selected 5wt% CO2–saturated biochar in the cement paste as taught by Gupta because i) there is a reasonable expectation of success that the disclosed amount would be suitable, ii) the CO2–saturated biochar can satisfy the designed strength grade for concrete constructions, iii) addition of the CO2–saturated biochar has better hydration and enhanced strength than control cementitious composition, while reducing associated CO2–eq emission, and iv) spent CO2–saturated at the end of service life from other industrial streams can be valorized as cementitious admixture.
Regarding claims 2 and 5-6, Gupta teaches the limitations as applied to claim 1 above, and Gupta further teaches wherein the cementitious composition comprises more than 5% in weight of the cementitious composition of carbonated biochar (claim 2), wherein the cementitious composition comprises up to 30% in weight of the cementitious composition of carbonated biochar (claim 5), and wherein the cementitious composition comprises up to 25% in weight of the cementitious composition of carbonated biochar (claim 6) (see claim 1 rejection for details, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have selected 5wt% CO2–saturated biochar in the cement paste as taught by Gupta because i) there is a reasonable expectation of success that the disclosed amount would be suitable, ii) the CO2–saturated biochar can satisfy the designed strength grade for concrete constructions, iii) addition of the CO2–saturated biochar has better hydration and enhanced strength than control cementitious composition, while reducing associated CO2–eq emission, and iv) spent CO2–saturated at the end of service life from other industrial streams can be valorized as cementitious admixture) (see MPEP 2144.05(I)).
Regarding claim 7, Gupta teaches the limitations as applied to claim 1 above, and Gupta further teaches the carbonated biochar contains at least 1% adsorbed carbon in weight of the carbonated biochar (see Gupta at page 6, left column, section 3.1, paragraph 2 teaching the produced biochar has 70.50% carbon by mass) (see MPEP 2144.05(I)).
Regarding claim 8, Gupta teaches the limitations as applied to claim 1 above, and Gupta further teaches wherein the cementitious composition contains from 70% to 99% of in weight of the cementitious composition of… cement (see Gupta at page 5, Table 3 teaching mixing proportions… SatBC-CP… cement paste with CO2–saturated biochar pre-deployment… cement 97.50g… biochar 2.50g… water 40g). One of ordinary skill in the art would appreciate that the total amount of components in SatBC-CP cement paste is 140g. There is 70 wt% (or (97.50 ÷ 140) x 100) cement in SatBC-CP cement paste (see MPEP 2144.05(I)).
Regarding claim 9, Gupta teaches the limitations as applied to claim 1 above, and Gupta further teaches wherein cementitious composition contains… a Portland cement (see Gupta at page 3, right column, section 2.1, paragraph 1 teaching ordinary Portland cement is used for preparation of cement pastes).
Regarding claim 10, Gupta teaches a method (see Gupta at page 3, right column, section 2 teaching materials and methods), comprising
a cementitious composition (see Gupta at page 4, left column, section 2.3 teaching four mixes are investigated in this disclosure including… cement paste). Cement paste is taken to meet the claimed “cementitious composition”,
with carbonated biochar as the main constituent (Gupta teaches this limitation as outlined below).
Gupta teaches cement paste with cement paste with 2.5% CO2-saturated biochar (SatBC-CP)… the dosage of biochar is selected based on the author’s previous findings – addition of 2– 5% wood biochar by weight of cement was found to improve hydration and compressive strength of mortar by 10-20% compared to control… while 2% wood-based biochar improved strength of cement mortar by 9% at 28-day age, addition of 5% biochar did not have significant effect on strength (see Gupta at page 4, left column, section 2.3)… the ground biochar… is saturated with CO2… the saturation point is reached when the pores of biochar are filled with CO2 (see Gupta at page 4, left column, section 2.2, paragraph 1). One of ordinary skill in the art would appreciate that 5wt% biochar did not have significant effect on strength of cement mortar compared to the 2% by weight of cement biochar, but still improved strength of cement mortar by 9% at 28-day age. CO2-saturated biochar (SatBC-CP) is taken to meet the claimed “carbonated biochar” based on specification at page 5 lines 23-25 disclosing carbonated biochar is disclosed as any biochar which, after being brought into contact with a gas flow enriched flow in CO2, retains part of it in its porous structure, and therefore contains adsorbed CO2. 5wt% biochar is taken to meet the claimed “as the main constituent” based on specification at page 6, lines 13-16 disclosing the term “main constituent of a cementitious composition” means any main constituent according to standard NF EN 197-1, that is to say any mineral material present in the cementitious composition in a proportion greater than 5% in the weight of the cementitious composition (see MPEP 2144.05(I)).
Gupta further teaches this disclosure also demonstrated a novel strategy of internal carbonation using biochar as storage site for carbon dioxide pre-deployment in cement… this strategy result in better hydration and enhanced strength than control, while reducing associated CO2–eq emission… applying this technique, spent CO2–saturated at the end of service life from other industrial streams can be valorized as cementitious admixture (see Gupta at page 18, right column, paragraph 1). Gupta also teaches the internal carbonation strategy, using CO2–saturated biochar, can enhance early (7 days) compressive strength by 25–30% and 12–15% compared to uncarbonated control and SF-CP… SatBC-CP offers similar strength as that of carbonated control and SF-CP after 28 days, indicating this type of biochar-cement can satisfy the designed strength grade for concrete constructions (see Gupta at page 19, left column, last bullet).
Additionally, MPEP states that "[w]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation", and “the normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages” (see MPEP § 2144.05.II.A).
It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention, to have selected 5wt% CO2–saturated biochar in the cement paste as taught by Gupta because i) there is a reasonable expectation of success that the disclosed amount would be suitable, ii) the CO2–saturated biochar can satisfy the designed strength grade for concrete constructions, iii) addition of the CO2–saturated biochar has better hydration and enhanced strength than control cementitious composition, while reducing associated CO2–eq emission, and iv) spent CO2–saturated at the end of service life from other industrial streams can be valorized as cementitious admixture.
Allowable Subject Matter
Claims 3-4 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten to overcome the rejection(s) under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), 2nd paragraph, set forth in this Office action and to include all of the limitations of the base claim and any intervening claims.
The following is a statement of reasons for the indication of allowable subject matter: the prior art fails to teach all the cumulative limitations of independent claim 1 and each of the respective dependent claims 3 and 4.
It is noted that Gupta teaches the limitations of independent claim 1, specifically 5wt% CO2–saturated biochar in the cement paste. However, Gupta fails to teach the claimed “wherein the cementitious composition comprises at least 8% in weight of the cementitious composition of carbonated biochar” (claim 3), and “wherein the cementitious composition comprises at least 10% of in weight of the cementitious composition carbonated biochar” (claim 4). And, there are no prior art references that provide adequate teachings or apparent reason that would lead the person of ordinary skill to modify Gupta as claimed in the respective dependent claims 3 and 4.
As such, the prior art fails to teach or render obvious the cumulative limitations of independent claim 1 and each of the respective dependent claims 3 and 4 as claimed. Therefore, the cumulative limitations of independent claim 1 and each of the respective dependent claims 3 and 4 are considered allowable.
Response to Arguments
Applicant's arguments filed 05/28/2026 have been fully considered but they are not persuasive.
Applicant discusses that the claimed 2-5% dosage range is drawn exclusively from Gupta’s prior work on as produced wood biochar (BC)… Gupta never discloses, suggests, or implies a 2-5% range for CO2-saturated biochar… it is a retrospective justification based on as-produced biochar data, not a disclosure of a workable range for CO2-saturated biochar… Gupta discloses a single fixed dosage of 2.5 wt% of cement; and the routine optimization rationale under 103 requires that the prior art disclose a range within which the claimed value falls, since Gupta does not disclose the range, the optimization argument lacks the necessary foundation (see Applicant’s arguments at page 4 paragraph 6 to page 5 paragraph 3).
Examiner acknowledges the arguments and respectfully notes that in response to applicant's arguments that the examiner's conclusion of obviousness is based upon “retrospective justification on as-produced biochar data” and “optimization argument lacks the necessary foundation”, it must be recognized that any judgment on obviousness is in a sense necessarily a reconstruction based upon hindsight reasoning. As long as the judgment on obviousness takes into account only knowledge which was within the level of ordinary skill at the time the claimed invention was made, and does not include knowledge gleaned only from the applicant's disclosure, such a reconstruction is proper (see MPEP § 2145.X.A).
In this instance, one of ordinary skill in the art would appreciate that 5wt% biochar can be added to a cementitious composition, and since i) using CO2-saturated biochar can enhance early (7 days) compressive strength by 25-30% and 12-15% compared to uncarbonated control, ii) SatBC-CP offers similar strength as the carbonated control, and iii) SatBC-CP can satisfy the designed strength grade for concrete constructions (see Gupta at page 19, section conclusions, last bullet, and see claim 1 rejection), and it is “the normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages” (see MPEP § 2144.05.II.A). There is a reasonable expectation of success when carbonated biochar is added up to the claimed range of “at least 5% in weight of the cementitious composition” that there is a carbon sequestering potential for the cement without loss of cement strength. Additionally, it is within the ability of the one skilled in the art, with the benefits of the teachings of Gupta to optimize the appropriate dosage of carbonated biochar from the previous studies.
Examiner notes that this factual situation do not constitute a new ground of rejection because it has been held that “if the examiner’s answer cites a different portion of an applied reference which goes no farther than, and merely elaborates upon, what is taught in the previously cited portion of that reference, then the rejection does not constitute a new ground of rejection” (see MPEP §1207.03(a).I).
As such, Gupta has reasonably met the limitations of independent claim 1, and the rejection is maintained.
Applicant discusses that one person of ordinary skill in the art would not assume that dosage data established for as-produced biochar (BC) and CO2-saturated biochar (SatBC) because the two systems differ in how CO2 is delivered to the cementitious matrix… Gupta reports materially different strength and carbonation depth… confirming that these are not interchangeable materials (see Applicant’s arguments at page 6 paragraph 2).
Examiner acknowledges the arguments and respectfully disagrees because it is “the normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages” (see MPEP § 2144.05.II.A). In this instance, Gupta teaches ‘in summary, this research illustrates the potential of biochar to manufacture low carbon cementitious building materials, that can turn future cities into “carbon sinks”’ (see Gupta at Abstract, last sentence). It is within the ability of the one skilled in the art, with the benefits of the teachings of Gupta to optimize the appropriate dosage of carbonated biochar from the previous studies because there is potential to manufacture low carbon cementitious building materials.
Examiner notes that this factual situation do not constitute a new ground of rejection because it has been held that “if the examiner’s answer cites a different portion of an applied reference which goes no farther than, and merely elaborates upon, what is taught in the previously cited portion of that reference, then the rejection does not constitute a new ground of rejection” (see MPEP §1207.03(a).I).
As such, Gupta has reasonably met the limitations of independent claim 1, and the rejection is maintained.
Applicant discusses that Gupta would have discouraged a skilled worker from increasing the quantity of CO2-saturaed biochar beyond 2.5% tested because: i) Gupta's own data would have discouraged a person of ordinary skill in the art from increasing the quantity of CO2-saturated biochar on hydration… Gupta presents the limited CO2 delivery of SatBC-CP as a deliberate and beneficial feature: because internal carbonation delivers less CO2 than external carbonation, more moisture is retained in the hardened paste, hydration is less disrupted, and strength is higher than in externally carbonated samples… Gupta is explicit that higher CO2 concentration, while accelerating carbonation and pore filling by carbonates, also consumes water in the pores of cement paste leading to interruption of the hydration reaction… increasing the quantity of CO2-saturated biochar may thus be seen as increasing the total CO2 delivered internally to the cementitious matrix, progressively eroding the very moisture-preservation advantage that Gupta identifies as the reason SatBC-CP outperforms externally carbonated samples; ii) Gupta identifies a structural weakening mechanism that is dose-dependent and applies to biochar generally - including CO2 -saturated biochar… Gupta reports this mechanism specifically in the context of as-produced biochar (BC-CP) under sealed curing: once the water retained in biochar pores is released, the empty macro-pores of biochar behave as weak zones, thus offsetting the benefits of improved hydration degree on strength development, which Gupta identifies as the reason BC-CP and the control show similar compressive strength at 28-day age under sealed curing; iii) even for as-produced biochar (BC) - the material for which the 2-5% range is disclosed - Gupta reports that addition of 5% biochar does not have significant effect on strength… if the upper bound of the disclosed range for as- produced biochar already yields no significant strength benefit, a person of ordinary skill in the art would have had no motivation to exceed that threshold for CO2- saturated biochar, which operates through a more limited and localised mechanism (see Applicant’s arguments at page 6 paragraph 3 to page 7 paragraph 2).
Examiner acknowledges the arguments and respectfully notes with respect to i) Gupta teaches that hydration is less affected in internally carbonated pastes compared to external carbonation (see Gupta at page 17, left column, paragraph 3, also shown with Examiner annotation below). In this instance, it is within the ability of the one skilled in the art, with the benefits of the teachings of Gupta to optimize the appropriate dosage of carbonated biochar from the previous studies.
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With respect to ii), it is “the normal desire of scientists or artisans to improve upon what is already generally known provides the motivation to determine where in a disclosed set of percentage ranges is the optimum combination of percentages” (see MPEP § 2144.05.II.A). It is within the ability of the one skilled in the art, with the benefits of the teachings of Gupta to optimize the appropriate dosage of carbonated biochar from the previous studies.
With respect to iii), MPEP states that “disclosed examples and preferred embodiments do not constitute a teaching away from a broader disclosure or nonpreferred embodiments” (see MPEP § 2123.II), and “a reference may be relied upon for all that it would have reasonably suggested to one having ordinary skill in the art, including nonpreferred embodiments” (see MPEP 2123.I). In this instance, 5% is not a teaching away, but a non-preferred embodiment. Gupta would still have reasonably suggested to one having ordinary skill in the art the claimed “at least 5% in weight of the cementitious composition”.
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.
Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARITES A GUINO-O UZZLE whose telephone number is (571)272-1039. The examiner can normally be reached M-F 8am-4pm EST.
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/MARITES A GUINO-O UZZLE/Examiner, Art Unit 1731
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