Prosecution Insights
Last updated: April 19, 2026
Application No. 18/287,794

PARALLEL-FLOW REGENERATIVE SHAFT KILN AND METHOD FOR BURNING CARBONATE ROCK

Non-Final OA §102§103§112
Filed
Oct 20, 2023
Examiner
WOLFORD, KURT JOSEPH
Art Unit
3762
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Thyssenkrupp AG
OA Round
1 (Non-Final)
74%
Grant Probability
Favorable
1-2
OA Rounds
2y 11m
To Grant
99%
With Interview

Examiner Intelligence

Grants 74% — above average
74%
Career Allow Rate
106 granted / 144 resolved
+3.6% vs TC avg
Strong +31% interview lift
Without
With
+30.6%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
19 currently pending
Career history
163
Total Applications
across all art units

Statute-Specific Performance

§101
0.2%
-39.8% vs TC avg
§103
52.0%
+12.0% vs TC avg
§102
18.0%
-22.0% vs TC avg
§112
24.3%
-15.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 144 resolved cases

Office Action

§102 §103 §112
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 Objections The claims are objected to because of the following informalities: Claim 32 should read, “… wherein Claim 36 should read, “… wherein Appropriate correction is required. Claim Interpretation Regarding claim 23, the claim recites, “the exhaust gas is heated by a heat exchanger and/or a solar device or a combustion reactor.” This limitation is being interpreted consistent with p. 5 para. 2 of the Specification, which states, “According to a further embodiment, the exhaust gas is heated by means of a heat exchanger and/or a heating device, in particular an electrical heating device, a solar device or a combustion reactor” Therefore, the claim is being interpreted to at least require one of a heat exchanger, a solar device, or a combustion reactor. Regarding claim 25, the claim recites “a heat exchanger for heating the exhaust gas”. The heat exchanger is being interpreted as the same heat exchanger recited in claim 23; in other words, claim 25 is being interpreted as positively requiring the exhaust gas to be heated by a heat exchanger, one of the options of claim 23. The following is a quotation of 35 U.S.C. 112(f): (f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph: An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked. As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph: (A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function; (B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and (C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function. Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function. Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function. Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. This application includes one or more claim limitations that do not use the word “means,” but are nonetheless being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, because the claim limitation(s) uses a generic placeholder that is coupled with functional language without reciting sufficient structure to perform the recited function and the generic placeholder is not preceded by a structural modifier. Such claim limitation(s) is/are: Cooling gas extraction device in claim 24, modified by the functional language of discharging the cooling gas heated in the cooling zone of the shaft, while not modified by sufficient structure, material, or acts for performing the claimed function. The Applicant’s PGPUB describes the cooling gas extraction device in para. 19, “The cooling gas extraction device preferably has a cooling gas outlet for discharging the cooling gas from the shaft.” And further in para. 38, “The cooling gas extraction device has, according to a further embodiment, a material-free space inside the cooling zone of the shaft. In particular, the material-free space is in the form of an external annular space which extends circumferentially around preferably the upper region of the cooling zone adjacent to the burning zone. In particular, the cooling gas outlet is arranged in the material-free annular space” Cooling gas extraction device in claim 27, modified by the functional language of discharging cooling gas from the cooling zone of the shaft, while not modified by sufficient structure, material, or acts for performing the claimed function. The Applicant’s PGPUB describes the cooling gas extraction device in paras. 19 and 38, as cited above. Please note: This claim is being interpreted as first introducing a cooling gas extraction device, see rejection under 112(b). Cooling gas extraction device in claim 33, modified by the functional language of “discharging cooling gas from the shaft”, while not modified by sufficient structure, material, or acts for performing the claimed function. The Applicant’s PGPUB describes the cooling gas extraction device in paras. 19 and 38, as cited above. Because this/these claim limitation(s) is/are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, it/they is/are being interpreted to cover the corresponding structure described in the specification as performing the claimed function, and equivalents thereof. If applicant does not intend to have this/these limitation(s) interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, applicant may: (1) amend the claim limitation(s) to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph (e.g., by reciting sufficient structure to perform the claimed function); or (2) present a sufficient showing that the claim limitation(s) recite(s) sufficient structure to perform the claimed function so as to avoid it/them being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. Claim Rejections - 35 USC § 112 The following is a quotation of 35 U.S.C. 112(b): (b) CONCLUSION.—The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention. The following is a quotation of 35 U.S.C. 112 (pre-AIA ), second paragraph: The specification shall conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the applicant regards as his invention. Claim 22-25, 27, and 32 are rejected under 35 U.S.C. 112(b) or 35 U.S.C. 112 (pre-AIA ), second paragraph, as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor (or for applications subject to pre-AIA 35 U.S.C. 112, the applicant), regards as the invention. Regarding claim 22, the phrase "in particular" renders the claim indefinite because it is unclear whether the limitations following the phrase are part of the claimed invention. See MPEP § 2173.05(d). For the purpose of substantive examination, Examiner will consider the claim as if reading, “… the exhaust gas is heated Claim 27 recites the limitation "the cooling gas extraction device". There is insufficient antecedent basis for this limitation in the claim. For the purpose of substantive examination, Examiner will consider the claim as if first introducing a cooling gas extraction device, interpreted in accordance with 112(f) as detailed above. Please note: It appears claim 27 may have been intended to ultimately depend from claim 24, which properly introduces a cooling gas extraction device. Clarification is kindly requested in any subsequent reply. Regarding claim 32, the phrase "in particular" renders the claim indefinite because it is unclear whether the limitations following the phrase are part of the claimed invention. See MPEP § 2173.05(d). For the purpose of substantive examination, Examiner will consider the claim as if reading, “… a heating devicebeing an electrical heating device, a solar device or a combustion reactor …” Further, claim 32 recites the limitation "…the gas inlet in the connecting channel and/or burning zone …". There is insufficient antecedent basis for this limitation in the claim. For the purpose of substantive examination, Examiner will consider the claim as if first requiring the gas inlet to be in the connecting channel and/or burning zone, by reciting, “… the gas inlet, which is in the connecting channel and/or burning zone, is a …”, note the use of two commas. It appears the claim may have been intended to depend from claim 31, which introduces the gas inlet arranged in the connecting channel and/or the burning zone, among other locations. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claim(s) 19-27 and 29-36 is/are rejected under 35 U.S.C. 102(a)(2) as being anticipated by WO 2022002869 A1 to Habib, cited in Applicants 10/20/2023 IDS and having an effectively filed date of 7/3/2020. Note: Reference is made to the attached translation of Habib. Regarding claim 19. Habib teaches a method for burning material in a parallel-flow regenerative shaft kiln (abstract, “The present invention relates to a method for calcining mineral rock in a regenerative parallel-flow vertical shaft furnace”), comprising: alternately operating a burning shaft and a regenerative shaft (p. 7 para. 2, “As can be seen in figure 1, the illustrated PFRK furnace is a straight double-vat 1, 2 where the fuel is injected alternately into one vat 1 and then into another 2 for approximately 12 'with a period of 'stop between cycles from G to 2' to reverse the circuits. This is the period of "inversion".”) which are connected to one another by a connecting channel (fig. 4, connecting flue 3), wherein the material flows through a material inlet into a preheating zone for preheating the material, a burning zone for burning the material and a cooling zone for cooling the material to a material outlet (p. 7 para. 2, “The tanks are † divided in height into three zones, the preheating zone A where the carbonate rock is † preheated before calcination, the combustion zone B where the firing of the carbonate rock takes place e † the cooling zone C where the cooling of the calcined material takes place.”); forming a concurrent burning zone in the burning shaft (p. 7 para. 2, “The carbonate rock, loaded at the top of the tank via an inlet 5 in the open position, gradually descends into the latter. Combustion air is introduced at the top of the tank through a supply opening 6, which allows combustion of the fuel at the outlet of the lances 4 e † decarbonation of the carbonate rock into calcined material 10. The current gas 11 formed by combustion and decarbonation descends in co- --> current of the calcined material and, via the peripheral channel 13, passes into the connecting flue 3.”); admitting a cooling gas into the cooling zone (p. 7 para. 2, “The cooling air is †, through a supply duct 7, introduced at the bottom of the tank, against -current of the calcined material, to cool it.”); discharging exhaust gas from one of the shafts via an exhaust gas outlet arranged inside or above the preheating zone (p. 7 para. 3, “After heat exchange with the descending calcined material 10, the heated cooling air mixes with the gas stream 11 which, coming from the connecting flue 3, reaches the tank through the peripheral channel 13. This gas stream 11 progresses to at the top of the bowl where it is evacuated from the oven through an exhaust duct 14 e † transferred to a chimney 15. In the bowl in cooking mode 1, this exhaust duct 14 is † closed.”); and wherein discharging the exhaust gas from one of the shafts via the exhaust gas outlet is at least partially introduced into at least one of the shafts (as seen in fig. 4 below, a portion of the exhaust gas in exhaust duct 14 is re-routed to the other shaft via the recirculation circuit 18). PNG media_image1.png 788 745 media_image1.png Greyscale Regarding claim 20. Habib teaches the method as claimed in claim 19, wherein the exhaust gas is introduced into the preheating zone of the burning shaft (fig. 4, the exhaust gas in recirculation circuit 18 is shown to be introduced in to the top, or preheating zone, of the burning shaft). Regarding claim 21. Habib teaches the method of claim 19, wherein the exhaust gas is introduced into the connecting channel and/or into the burning zone of the regenerative shaft (pp. 9-10, “It is also possible to further provide, in the connecting flue 3 and the peripheral channels 13, an injection of a fraction of said part taken from the gaseous effluent discharged from the furnace via an injection pipe 37.”). Regarding claim 22. Habib teaches the method of claim 21 wherein, before being introduced into the connecting channel or into the burning zone of the regenerative shaft, the exhaust gas is heated to a temperature of 900°C to 1100°C (p. 7 para. 7, the operating temperature of the system is described as being “much higher than 900°C”. Therefore, it is understood that the recirculated gas would be heated to a similar temperature, i.e. above 900°C). Regarding claim 23. Habib teaches the method of claim 22 wherein, the exhaust gas is heated by a heat exchanger (fig. 4, heat exchanger 36, p. 9 para. 4) and/or a solar device or a combustion reactor (optional limitations, see mapping to alternative). Regarding claim 25. Habib teaches the method of claim 23 wherein, the cooling gas discharged from the cooling zone is fed to a heat exchanger for heating the exhaust gas (fig. 4, the cooling gas from collecting ring 25 is sent to the heat exchanger 36). Regarding claim 27. Habib teaches the method of claim 25 wherein, the content of oxygen and/or CO2 in the exhaust gas and/or the cooling gas is determined (p. 8 para. 7 and p. 9 para. 1 describes a process in which the content of oxygen in the cooling gas is determined, cooling gas being air has an oxygen content of 23%, see p. 7 last paragraph, and the exhaust gas is described has having a CO2 and p. 9 para. 1 describes, “a tailor-made CO2 concentration between 40% and 65% by volume of CO2 can be established at the stack by adjusting the amount of cooling air between 100% and 50% of the minimum thermodynamic volume required to cool the stack.”) and wherein the amount of oxidizing agent fed to the burning shaft (p. 8 para. 9, “.sup.830 Nm 3 / † of gaseous effluent discharged from the furnace, rich in CO2, is taken through the recirculation pipe 18. .sup.160 Nm 3 / † of O2 are mixed with this recirculated effluent, so as to keep in the oxidizing mixture thus formed the same mass concentration of 23% of O2 e † to obtain during combustion the same excess oxygen of 19% by weight relative to stoichiometric requirements.”) and/or the amount of cooling gas discharged from the cooling zone of the shaft via the cooling gas extraction device is controlled (p. 9 para. 1, “The tanks 1 and 2 are each provided, below the connecting flue 3 and the peripheral channels 13, with a collecting ring 25 which communicates with a draw-off element 26 so as to allow extraction of the air from the furnace. heated cooling. In this way, part or all of the combustion air can be withdrawn, if necessary also withdrawing a small proportion of the combustion fumes.”). Regarding claim 24. Habib teaches the method of claim 22 wherein, the cooling gas heated in the cooling zone is discharged from the cooling zone of the shaft via a cooling gas extraction device (fig. 4, withdrawal element 26, p. 9 para. 3). Regarding claim 26. Habib teaches the method of claim 19 wherein, an oxidizing agent is fed to the shaft operated as a burning shaft (p. 7 para. 2, “Combustion air is introduced at the top of the tank through a supply opening 6, which allows combustion of the fuel at the outlet of the lances 4 e † decarbonation of the carbonate rock into calcined material 10.”). Regarding claim 29. Habib teaches a parallel-flow regenerative shaft kiln for burning and cooling material (abstract, “The present invention relates to a method for calcining mineral rock in a regenerative parallel-flow vertical shaft furnace,”), comprising: two shafts which can be operated alternately as a burning shaft and as a regenerative shaft (p. 7 para. 2, “As can be seen in figure 1, the illustrated PFRK furnace is a straight double-vat 1, 2 where the fuel is injected alternately into one vat 1 and then into another 2 for approximately 12 'with a period of 'stop between cycles from G to 2' to reverse the circuits. This is the period of "inversion".”) and are connected to one another by means of a connecting channel (fig. 4, connecting flue 3), wherein a concurrent burning zone is formed in the shaft operated as a burning shaft (p. 7 para. 2, “The carbonate rock, loaded at the top of the tank via an inlet 5 in the open position, gradually descends into the latter. Combustion air is introduced at the top of the tank through a supply opening 6, which allows combustion of the fuel at the outlet of the lances 4 e † decarbonation of the carbonate rock into calcined material 10. The current gas 11 formed by combustion and decarbonation descends in co- --> current of the calcined material and, via the peripheral channel 13, passes into the connecting flue 3.”), wherein each shaft includes, in a direction of flow of the material, a preheating zone for preheating the material, a burning zone for burning the material and a cooling zone for cooling the material (p. 7 para. 2, “The tanks are † divided in height into three zones, the preheating zone A where the carbonate rock is † preheated before calcination, the combustion zone B where the firing of the carbonate rock takes place e † the cooling zone C where the cooling of the calcined material takes place.”), and wherein each shaft includes an exhaust gas outlet arranged inside or above the preheating zone for discharging exhaust gas from the shaft (p. 7 para. 3, “After heat exchange with the descending calcined material 10, the heated cooling air mixes with the gas stream 11 which, coming from the connecting flue 3, reaches the tank through the peripheral channel 13. This gas stream 11 progresses to at the top of the bowl where it is evacuated from the oven through an exhaust duct 14 e † transferred to a chimney 15. In the bowl in cooking mode 1, this exhaust duct 14 is † closed.”), wherein at least one exhaust gas outlet is connected to a gas inlet for admitting gas into at least one shaft (as seen in fig. 4 below, a portion of the exhaust gas in exhaust duct 14 is re-routed to the other shaft via the recirculation circuit 18). PNG media_image1.png 788 745 media_image1.png Greyscale Regarding claim 30. Habib teaches the parallel-flow regenerative shaft kiln of claim 29, wherein the gas inlet is arranged in the preheating zone of the shaft operated as a burning shaft (fig. 4, the exhaust gas in recirculation circuit 18 is shown to be introduced in to the top, or preheating zone, of the burning shaft). Regarding claim 31. Habib teaches the parallel-flow regenerative shaft kiln of claim 29, wherein the gas inlet is arranged in the connecting channel and/or the burning zone of the shaft and/or a material-free space in the shaft (pp. 9-10, “It is also possible to further provide, in the connecting flue 3 and the peripheral channels 13, an injection of a fraction of said part taken from the gaseous effluent discharged from the furnace via an injection pipe 37.” See fig. 4). Regarding claim 32. Habib teaches the parallel-flow regenerative shaft kiln of claim 29, wherein arranged between the exhaust gas outlet and the gas inlet, which is in the connecting channel and/or burning zone (i.e. along recirculation circuit 18), is a heat exchanger (fig. 4, heat exchanger 36, p. 9 para. 4) and/or a heating device being an electrical heating device, a solar device or a combustion reactor (optional limitations, see mapping to alternative), for heating the exhaust gas (p. 9 para. 4). Regarding claim 33. Habib teaches the parallel-flow regenerative shaft kiln of claim 29, wherein the cooling zone includes a cooling gas inlet for admitting cooling gas into the cooling zone (fig. 4, supply duct 7) and a cooling gas extraction device for discharging cooling gas from the shaft (fig. 4, collecting ring 25 and draw off element 26). Regarding claim 34. Habib teaches the parallel-flow regenerative shaft kiln of claim 33, wherein the cooling gas extraction device is connected to a heat exchanger for heating the exhaust gas (fig. 4, the cooling gas from collecting ring 25 is sent to the heat exchanger 36). Regarding claim 35. Habib teaches the parallel-flow regenerative shaft kiln of claim 33, wherein the cooling gas extraction device comprises a material-free space inside the cooling zone (fig. 4, it is understood that the collecting ring 25, per se, is not entirely full of material). Regarding claim 36. Habib teaches the parallel-flow regenerative shaft kiln of claim 29, wherein each shaft includes a combustion gas inlet for admitting combustion gas into the preheating zone and/or the burning zone (fig. 4, supply opening 6) and wherein the combustion gas inlet is connected to an oxidizing agent line for conducting an oxidizing agent into the shaft (p. 8 para. 7, “A separation unit --> air 20 separates from the air supplied by pipe 21 with N2 discharged through pipe 22 and with O2 supplied to recirculation circuit 18 via supply pipe 23. This circuit 18 then conducts the oxidant mixture formed from the fraction recirculated gas effluent and concentrated O2 to the sum † of each of the tanks at the supply opening 6.”). 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. Claim(s) 28 is/are rejected under 35 U.S.C. 103 as being unpatentable over Habib as applied to claim 19 above, and further in view of CN 105026333 A to Pringer. Note: Reference is made to the attached translation of Pringer. Regarding claim 28. Habib teaches the method of claim 19 wherein the shafts each have at least one burner lance (fig. 4, lances 4, p. 7 para. 2, “When a tank is in cooking mode, here tank 1, a fuel supply device in the form of lances 4 injects into the tank a fuel 9, which, in the example illustrated, is natural gas.”) But fails to teach wherein the exhaust gas is introduced into the burner lance. Pringer teaches an exhaust gas introduced into a burner lance (p. 4 para. 4, “An inert or oxygen-depleted gas, especially nitrogen, carbon dioxide or kiln exhaust gas, via a burner lance is provided as coal transport medium. the coal gas for cooling and for realizing low-oxygen atmosphere in the burner tip region;”). 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 device of Habib to implement a suitable burner lance, as taught by Pringer, which supplies coal via transport medium being kiln exhaust gas. This would provide the predictable result and benefit of suitably allowing for coal to be used as the fuel source, as suggested by Pringer in the abstract. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to Kurt J Wolford whose telephone number is (571)272-9945. The examiner can normally be reached 7:30 AM - 4:00 PM. Examiner interviews are available via telephone, in-person, and video conferencing using a USPTO supplied web-based collaboration tool. To schedule an interview, applicant is encouraged to use the USPTO Automated Interview Request (AIR) at http://www.uspto.gov/interviewpractice. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Michael G Hoang can be reached at (571)272-6460. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of published or unpublished applications may be obtained from Patent Center. Unpublished application information in Patent Center is available to registered users. To file and manage patent submissions in Patent Center, visit: https://patentcenter.uspto.gov. Visit https://www.uspto.gov/patents/apply/patent-center for more information about Patent Center and https://www.uspto.gov/patents/docx for information about filing in DOCX format. For additional questions, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /KURT J WOLFORD/Examiner, Art Unit 3762 /MICHAEL G HOANG/Supervisory Patent Examiner, Art Unit 3762
Read full office action

Prosecution Timeline

Oct 20, 2023
Application Filed
Feb 07, 2026
Non-Final Rejection — §102, §103, §112 (current)

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Prosecution Projections

1-2
Expected OA Rounds
74%
Grant Probability
99%
With Interview (+30.6%)
2y 11m
Median Time to Grant
Low
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