Prosecution Insights
Last updated: August 18, 2026
Application No. 19/228,821

LEAN BURN COMBUSTOR

Final Rejection §103§112
Filed
Jun 05, 2025
Priority
Jun 10, 2024 — GB 2408247.1 +1 more
Examiner
DUGER, JASON H
Art Unit
3741
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Rolls-Royce plc
OA Round
2 (Final)
70%
Grant Probability
Favorable
3-4
OA Rounds
1y 10m
Est. Remaining
99%
With Interview

Examiner Intelligence

Grants 70% — above average
70%
Career Allowance Rate
328 granted / 465 resolved
+0.5% vs TC avg
Strong +51% interview lift
Without
With
+51.4%
Interview Lift
resolved cases with interview
Typical timeline
3y 1m
Avg Prosecution
18 currently pending
Career history
495
Total Applications
across all art units

Statute-Specific Performance

§101
1.3%
-38.7% vs TC avg
§103
44.2%
+4.2% vs TC avg
§102
9.8%
-30.2% vs TC avg
§112
41.3%
+1.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 465 resolved cases

Office Action

§103 §112
DETAILED ACTION This Office Action is responsive to Applicant’s reply filed 04/30/2026. Claims 1-20 are pending. 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 . 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 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. Prior Art Relied Upon This action references the following issued US Patents and/or Patent Application Publications: US PATENT or PUBLICATION NUMBER HEREINAFTER US-11643979-B1 “BEMMENT” US-20070125093-A1 “BURD” US-20130125556-A1 “HOKE” US-20200141330-A1 “LLANO” US-12018841-B1 “MADDEN” US-20230332543-A1 “BEMMENT-543” This action references the following non-patent documents: AUTHOR OR EDITOR TITLE (DATE), PUBLISHER, EDITION CHAPTERS / PAGES COPY HEREINAFTER Durdina et al. Reduction of Nonvolatile Particulate Matter Emissions of a Commercial Turbofan Engine at the Ground Level from the Use of a Sustainable Aviation Fuel Blend [2021], American Chemical Society ALL PROVIDED “DURDINA” Information Disclosure Statement The listing of references in the specification is not a proper information disclosure statement. 37 CFR 1.98(b) requires a list of all patents, publications, or other information submitted for consideration by the Office, and MPEP § 609.04(a) states, "the list may not be incorporated into the specification but must be submitted in a separate paper." Therefore, unless the references have been cited by the examiner on form PTO-892, they have not been considered. See SPEC pages 82-93 (Durand 2023, Harper 2022 and Saffaripour 2019) have included. 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. Claims 1-8, 10-11 and 18-20 are rejected under 35 U.S.C. 103 as being unpatentable over BEMMENT in view of BURD and DURDINA. Re Claims 1, 19 and 20 BEMMENT teaches a gas turbine engine 10 for an aircraft and method for operating the gas turbine engine (claims 19-20), the engine comprising: a controller [EEC 42]; a bypass duct 22; an engine core 11 with a combustor 16 having a number of fuel spray nozzles [fuel injectors] (29:21-26, 62:6-18); and a fuel distribution valve configured to control fuel to the combustor (53:39-49, 66:46 to 67:21); wherein: a bypass ratio defined as a ratio of mass flow rate through the bypass duct to mass flow rate through the engine core is at least 6.66 at cruise conditions (20:22-42) the controller is configured to separately provide 7% available thrust for given operating conditions [idle] and 100% available thrust for the given operating conditions [take-off] (23:39 to 24:7; see also 24:8 to 25:48, 33:22-33 and 35:55 to 38:40); a first idle-MTO nvPM emission index ratio is: ( EIidle / EImaxTO ) EIidle is a system corrected nvPM emissions index in mg/kg of the gas turbine engine if operating at around 7% available thrust for the given operating conditions; EImaxTO is a system corrected nvPM emissions index in mg/kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions (a first idle-MTO nvPM emission index ratio as defined is necessarily present where the gas turbine is operated at idle and take-off as described at 23:39 to 24:7; see also 31:5-13 and 66:46-61); the gas turbine engine is configured so that the first idle-MTO nvPM emissions index ratio of the gas turbine engine is a value when the fuel delivered to the combustor comprises a sustainable aviation fuel (31:5-13 and 66:46 to 67:33). BEMMENT also teaches the method comprises providing fuel comprising the sustainable aviation fuel to the fuel spray nozzles and providing fuel comprising sustainable aviation fuel to the fuel spray nozzles to operate the gas turbine engine at around 7% available thrust for the given operating conditions and to operate the gas turbine engine at around 100% available thrust for the given operating conditions, such that the first idle-MTO nvPM emissions index ratio of the gas turbine engine is a necessarily a value. (BEMMENT at 23:39 to 24:7; see also 24:8 to 25:48, 33:22-33 and 35:55 to 38:40). However, BEMMENT as discussed so far fails to expressly teach the controller is configured to control the fuel distribution valve to separately provide 7% available thrust for the given operating conditions and 100% available thrust for the given operating conditions. BEMMENT further teaches the controller is configured to control the fuel distribution valve to separately provide desired characteristics at particular operating conditions (53:39-49, 66:46 to 67:21) and that the particular operating conditions include take-off and idle (23:39 to 24:7). It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the engine such that the controller is configured to control the fuel distribution valve to separately provide 7% available thrust for the given operating conditions and 100% available thrust for the given operating conditions in order to automatically operate an aircraft engine according to one or more variable fuel characteristics without intervention of a pilot for efficient, tailored control of the propulsion system (67:34-50, 34:31-45). BEMMENT notes multiple combustor types may be used, including rich and lean combustion (62:6-27). However, BEMMENT fails to specify the combustor is a rich burn, quick quench, lean burn (RQL) combustor having the number of fuel spray nozzles in the range of 14-22 and having, along a length of the combustor, a rich zone, a quick quench zone and a lean zone the RQL combustor is configured to burn fuel at a fuel/air ratio higher than stoichiometric in the rich zone and add air to quench combustion so that the fuel/air ratio transitions to lower than stoichiometric in the quick quench zone BURD teaches a gas turbine engine for an aircraft and a method of operating the same (¶¶0029-0036), the engine comprising a rich burn, quick quench, lean burn (RQL) combustor (¶¶0030-0036) having a number of fuel spray nozzles in the range of 14-22 (¶0031), the combustor having, along a length of the combustor, a rich zone, a quick quench zone and a lean zone the RQL combustor is configured to burn fuel at a fuel/air ratio higher than stoichiometric in the rich zone and add air to quench combustion so that the fuel/air ratio transitions to lower than stoichiometric in the quick quench zone (¶¶0035-0036; see also ¶¶0003-0008). It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the engine of BEMMENT wherein the combustor is a rich burn, quick quench, lean burn (RQL) combustor and having the number of fuel spray nozzles in the range of 14-22 and having, along a length of the combustor, a rich zone, a quick quench zone and a lean zone the RQL combustor is configured to burn fuel at a fuel/air ratio higher than stoichiometric in the rich zone and add air to quench combustion so that the fuel/air ratio transitions to lower than stoichiometric in the quick quench zone, in order to provide a desirably sized engine (¶0031) with a combustor able to balance performance, emissions formation/output and residence time (¶¶0040-0041). However, BEMMENT in view of BURD as discussed so far fails to teach wherein the gas turbine engine is configured so that the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8 when the fuel delivered to the RQL combustor comprises a sustainable aviation fuel. DURDINA teaches a gas turbine engine and a method of operating the same (pages 14576-14582) the engine having operating at a first idle-MTO nvPM emissions index ratio that is defined as: E I i d l e E I m a x T O where: EIidle is the system loss corrected (page 14580) nvPM emissions index in mg/kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions (Fig. 2; page 14580); and EImaxTO is the system loss corrected (page 14580) nvPM emissions index in mg/kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions (Fig. 2; page 14580), and where the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8 (see annotated Image and further discussion below). For example, referring to Figure 2A and the Image below, first idle-MTO nvPM emissions index ratio using sustainable aviation fuel HEFA-SPK blend corresponds to about (2.5 / 187) at point annotated “A” and point annotated “C” below, i.e., a value of ~ 0.013369, well below 0.8. NOTE either of these data points at “B” or “A” in the annotations of the Image below (also annotated “AROUND 7% AVAILABLE THRUST) qualify as around 7%. Notably, even without extrapolating specific values for the emission indexes, done above for Applicant’s convenience, one of ordinary skill would have appreciated from Figure 2A DURDINA teaches first idle-MTO nvPM emissions index ratio less than 0.8 in Figure 2A for both sustainable aviation fuel and for hydrocarbon fuel. . PNG media_image1.png 1133 1077 media_image1.png Greyscale It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the engine of BEMMENT in view of BURD such that the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8 as taught by DURDINA, in order to reduce particulate emissions at desired conditions utilizing environmentally friendly fuel (DURDINA pages 14576-14577). See also BEMMENT 29:6 to 30:16. It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the method wherein it comprises provide fuel comprising the sustainable aviation fuel to the fuel spray nozzles and providing fuel comprising sustainable aviation fuel to the fuel spray nozzles to operate the gas turbine engine at around 7% available thrust for the given operating conditions and to operate the gas turbine engine at around 100% available thrust for the given operating conditions such that the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8, as taught by DURDINA, in order to reduce particulate emissions at desired conditions utilizing environmentally friendly fuel (DURDINA pages 14576-14577). See also BEMMENT 29:6 to 30:16. Re Claims 2-6, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1 as discussed above, wherein the first idle-MTO nvPM emissions index ratio is 0.013369 as discussed above in Claim 1. As such, BEMMENT in view of BURD and DURDINA renders obvious the values for the first idle-MTO nvPM emissions index ratio claimed in Claims 2-6 (wherein the first idle-MTO nvPM emissions index ratio is less than 0.708; wherein the first idle-MTO nvPM emissions index ratio is less than or equal to 0.5; wherein the first idle-MTO nvPM emissions index ratio is less than or equal to 0.105; wherein the first idle-MTO nvPM emissions index ratio is greater than or equal to 0.0103; wherein the first idle-MTO nvPM emissions index ratio is in the range of 0.0103 to 0.105), which would have been obvious to provide for the reasons discussed in Claim 1 above. Re Claim 7 , BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1, wherein a second idle-MTO nvPM emissions index ratio is defined as: E I i d l e ,   S A F E I m a x T O ,   S A F E I i d l e ,     F F E I m a x T O ,   F F where: EIidle,SAF is the system loss corrected nvPM emissions index in mg/kg of the gas turbine engine if operating at around 7% available thrust for the given operating conditions, or for other different operating conditions, and if the fuel provided to the combustor comprises the sustainable aviation fuel; EImaxTO,SAF is the system loss corrected nvPM emissions index in mg/kg of the gas turbine engine if operating at around 100% available thrust for the same given operating conditions at which EIidle,SAF is calculated, and if the fuel provided to the combustor comprises the sustainable aviation fuel; EIidle,FF is the system loss corrected nvPM emissions index in mg/kg of the gas turbine engine if operating at around 7% available thrust for the same given operating conditions at which EIidle,SAF is calculated, and if a fuel provided to the combustor is the fossil-based hydrocarbon fuel; EImaxTO,FF is the system loss corrected nvPM emissions index in mg/kg of the gas turbine engine if operating at around 100% available thrust for the same given operating conditions at which EIidle,SAF is calculated, and if a fuel provided to the combustor is the fossil-based hydrocarbon fuel. The above second idle-MTO nvPM emissions index ratio is necessarily present in BEMMENT in view of BURD and DURDINA. However, BEMMENT in view of BURD and DURDINA as discussed so far fails to teach wherein the second idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 1. DURDINA further teaches for sustainable aviation fuel [HEFA-SPK blend] in Figure 2A that EI--idle,SAF / EImaxTO,SAF is about 0.013 [2.5 / 187] (at points “A” and “C” as labeled in the Image above). DURDINA further teaches for fossil-based hydrocarbon fuel [JET A-1] in Figure 2A that EI--idle,FF / EImaxTO,FF is about 0.022 [5 / 230] (at points “A” and “C” as labeled in the Image above). As such, in Figure 2A DURDINA teaches a second idle-MTO nvPM emissions of 0.59, which is less than one. It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide wherein the second idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 1 for the reasons discussed above with respect to DURDINA in Claim 1. Relied upon values are also shown in the annotated Image below. PNG media_image2.png 1014 1024 media_image2.png Greyscale Re Claims 8 and 10-11, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1 as discussed above, wherein the second idle-MTO nvPM emissions index ratio is 0.059 as discussed above. As such, BEMMENT in view of BURD and DURDINA renders obvious the values for the second idle-MTO nvPM emissions index ratio claimed in Claims 8, 10-11 (second idle-MTO nvPM emissions index ratio is less than or equal to 0.8; second idle-MTO nvPM emissions index ratio is greater than or equal to 0.03; second idle-MTO nvPM emissions index ratio is greater than or equal to 0.118), which would have been obvious to provide for the reasons discussed in Claim 1 above. Re Claim 18, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1, but as discussed so far fails to teach wherein the fuel provided to the combustor comprises 50% to 100% of the sustainable aviation fuel. BEMMENT further teaches wherein the fuel provided to the combustor comprises a 50% to 100% of the sustainable aviation fuel (claim 19; 29:48-56). It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide wherein the fuel provided to the combustor further comprises a 50% to 100% of the sustainable aviation fuel, in order to control a control parameter based on fuel characteristics (66:26 to 67:9). Additionally, referring to Figure 2A of DURDINA, while one of ordinary skill would appreciate that increasing a blended amount of HEFA-SPK would be likely to decrease EImass at 7%, 100% available thrust a certain amount, they would also appreciate that given 50% hydrocarbon Jet A-1 EI mg/kg at 100 percent thrust would certainly not fall below 75 mg/kg in view of Figure 2A (which shows 230 mg/kg for 100% Jet A-1 and 186 mg/kg for 68% Jet A-1 at 100% available thrust) and as such would have appreciated that the first idle-MTO nvPM emissions index ratio of the gas turbine engine would remain substantially less than 0.8. It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the fuel provided to the combustor comprises a 50% to 100% of the sustainable aviation fuel and the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8 to meet desired emissions levels (BEMMENT 31:5-13 and 66:46 to 67:33). Claims 9 and 12 are rejected under 35 U.S.C. 103 as being unpatentable over BEMMENT in view of BURD and DURDINA as applied above, further in view of MADDEN. Re Claims 9 and 12, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1, but as discussed so far fails to teach wherein the second idle-MTO nvPM emissions index ratio is less than or equal to 0.178 / wherein the second idle-MTO nvPM emissions index ratio is in the range 0.118 to 0.178. As discussed above, second idle-MTO nvPM emissions index ratio is governed by EIidle (at around 7% available thrust) and EImaxTO (at around 100 % available thrust) for sustainable and hydrocarbon fuel. MADDEN further teaches emissions index EIidle (at around 7% available thrust) and emissions index EImaxTO (at around 100 % available thrust) are result effective variables routinely optimized by a controller of a gas turbine engine (9:43 to 15:11) to achieve the recognized result of accounting for fuel properties of different fuels such as hydrocarbon and sustainable aviation fuels and to adjust methods of operating a gas turbine accordingly (1:21-28) accounting for emissions output (9:43 to 15:11) in compliance with regulations. Notably, the number of particles per kg dictate the mg per kilogram for each emissions index. Therefore, it would have been obvious to one having ordinary skill in the art at the time of the invention to modify the gas turbine engine such that the controller controls the engine to achieve a second idle-MTO nvPM emissions index ratio that is less than or equal to 0.178 and in the range 0.118 to 0.178, in order to account for fuel properties of different fuels such as hydrocarbon and sustainable aviation fuels and to adjust methods of operating a gas turbine accordingly, since it has been held that the optimization of result effective variables by routine experimentation was an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) and In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977). MPEP 2144.05 II. Claims 13-16 are rejected under 35 U.S.C. 103 as being unpatentable over BEMMENT in view of BURD and DURDINA as applied above, further in view of HOKE. Re Claims 13-15, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1, but as discussed so far fails to teach wherein the fuel spray nozzles comprises one or more duplex nozzles and one or more single flow nozzles, wherein the duplex fuel spray nozzles are arranged in groups about the circumference of the combustor, wherein each group of duplex fuel spray nozzles comprises 2-8 nozzles. HOKE teaches fuel spray nozzles comprising one or more duplex nozzles and one or more single flow nozzles (Fig. 3; ¶¶0020-0023, 0027-0028) wherein the duplex fuel spray nozzles are arranged in groups about the circumference of the combustor (Fig. 3, ¶¶0027-0028) wherein each group of duplex fuel spray nozzles comprises 2-8 nozzles (Fig. 3). It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the engine such that the fuel spray nozzles comprises one or more duplex nozzles and one or more single flow nozzles, wherein the duplex fuel spray nozzles are arranged in groups about the circumference of the combustor, and wherein each group of duplex fuel spray nozzles comprises 2-8 nozzles (Fig. 3), in order to provide differential coupling to the associated occurring acoustic frequencies (HOKE ¶¶0027-0028). Re Claim 16, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 13 as discussed above, but as discussed so far fails to teach wherein the combustor comprises one or more ignitors and the one or more ignitors are arranged adjacent to one or more of the duplex fuel spray nozzles. HOKE further teaches the combustor comprises one or more ignitors 124 and the one or more ignitors are arranged adjacent to one or more of the duplex fuel spray nozzles (¶0028). It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the engine wherein the combustor comprises one or more ignitors arranged adjacent to one or more of the duplex fuel spray nozzles, in order to provide differential coupling to the associated occurring acoustic frequencies (HOKE ¶¶0027-0028). Claim 17 is rejected under 35 U.S.C. 103 as being unpatentable over BEMMENT in view of BURD and DURDINA as applied above, further in view of LLANO. Re Claim 17, BEMMENT in view of BURD and DURDINA teaches the gas turbine engine of claim 1, the engine necessarily including number of fuel spray nozzles per unit engine core size. However, BEMMENT in view of BURD and DURDINA as discussed so far fails to teach wherein the number of fuel spray nozzles per unit engine core size is in the range of 2.5 to 4.5. BURD teaches number of fuel nozzles is result effective routinely optimized for desired engine size (BURD ¶0031). LLANO teaches a high pressure compressor with a core size defined as mass flow * T0.5 / P (LLANO ¶¶0084, 0089) and teaches that the core size is a result effective variable routinely optimized and modulated for a given number of fuel nozzles for achieving engine temperatures and powers for given power conditions (¶¶0089-0097; Figs. 5-8). It would have been obvious to one having ordinary skill in the art prior to the effective filing date of the claimed invention to provide the gas turbine engine so the number of fuel spray nozzles per unit engine core size is in the range 2.5 to 4.5, in order to achieve desired engine power and temperatures and/or improved compressor operability and/or reduced ground idle thrust and/or cooling modulation and/or reduced cooling flow and/or improved fuel consumption (LLANO ¶¶0091, 0096, 0118-0125) and since it has been held that the optimization of result effective variables by routine experimentation was an obvious extension of prior art teachings. In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955) and In re Antonie, 559 F.2d 618, 195 USPQ 6 (CCPA 1977). See MPEP 2144.05 II. Response to Arguments Applicant’s arguments filed 04/30/2026 have been fully considered. Applicant’s amendment overcame the prior rejections under 35 U.S.C. 112(b). With respect to system loss corrected, the rejection was overcome because in view of the amendment replacing “the” with “a” it is now clear that system loss corrected can have any art recognized meaning Applicant’s arguments to the prior art rejections are not found persuasive. The examiner appreciates facts presented by Applicant to the CFM56-7B engine presented by Applicant. However, the rejections are based upon the combined teachings of the prior art. The primary reference BEMMENT suggests numerous modifications and variations may be made to the engine (see BEMMENT 17:1 to 25:26 and BEMMENT 62:6-19). These include both bypass ratios (20:22-42) and both rich and lean combustion types (62:6-19). Additionally, the prior art also recognizes that the level of nvPM (non-volatile particulate matter) emissions may be controlled via fuel selection and/or blending (BEMMENT 29:7-38, 31:5-14, 66:46-62; BEMMENT-543 ¶0215; DURDINA page 14576) in order to reduce contrails and/or reduce negative environmental impact (BEMMENT 29:7-38, 31:5-14, 66:46-62; BEMMENT-543 ¶0215; DURDINA page 14576, 14582). This is also evidenced by the prior art submitted by Applicant in the most recent IDS, which has not been applied (See US 12,018,841 at e.g., 8:7 to 13:24). Since primary reference BEMMENT is suggestive of fuel selection and blending choices with respect to particulate matter, and DURDINA suggests the values in the claimed range would provide a benefit (DURDINA 14582), the combination of references would suggest providing first idle-MTO nvPM emission index within the claimed range, even for engines that may vary slightly in bypass ratio and/or combustor type. The prior art applied is analogous art and has been considered in its entirety. Where the teachings of two or more prior art references conflict, the power of each reference to suggest solutions to one of ordinary skill in the art has been weighed, considering the degree to which one reference might accurately discredit another. The additional teachings of DURDINA do not conflict with, much less outweigh, the teachings of BEMMENT. Applicant's arguments appear to hinge on a bodily incorporation of DURDINA into the primary reference rather than considering what the combined teachings of the prior art would have suggested to one of ordinary skill. “The test for obviousness is not whether the features of a secondary reference may be bodily incorporated into the structure of the primary reference.... Rather, the test is what the combined teachings of those references would have suggested to those of ordinary skill in the art.” In re Keller, 642 F.2d 413, 425, 208 USPQ 871, 881 (CCPA 1981). See MPEP § 2145 (III). One cannot show nonobviousness by attacking references individually where the rejections are based on combinations of references. In re Keller, 642 F.2d 413, 208 USPQ 871 (CCPA 1981); In re Merck & Co., Inc., 800 F.2d 1091, 231 USPQ 375 (Fed. Cir. 1986). Furthermore, the proposed combination of the prior art would not change the principle of operation of the prior art invention being modified or render the reference inoperable for its intended purpose. 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. Correspondence Any inquiry concerning this communication or earlier communications from the examiner should be directed to JASON H DUGER whose telephone number is (313) 446-6536. The examiner can normally be reached 8:30a to 4:30p EST Monday & Tuesday and 8:00a to 2:00p Wednesday, and is OFF Thursday and Friday. 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, Phutthiwat Wongwian, can be reached on (571) 270-5426. The fax phone number for the organization where this application or proceeding is assigned is (571) 273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. JASON H DUGER PRIMARY EXAMINER, ART UNIT 3741 PHONE (313) 446 6536 FAX (571) 270 9083 DATE July 16, 2026 /JASON H DUGER/Primary Examiner, Art Unit 3741
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Prosecution Timeline

Jun 05, 2025
Application Filed
Feb 05, 2026
Non-Final Rejection mailed — §103, §112
Mar 05, 2026
Examiner Interview (Telephonic)
Mar 05, 2026
Examiner Interview Summary
Apr 30, 2026
Response Filed
Jul 21, 2026
Final Rejection mailed — §103, §112 (current)

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Prosecution Projections

3-4
Expected OA Rounds
70%
Grant Probability
99%
With Interview (+51.4%)
3y 1m (~1y 10m remaining)
Median Time to Grant
Moderate
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