Prosecution Insights
Last updated: April 19, 2026
Application No. 18/753,370

ACTUATED GAS TURBINE ENGINE SYSTEMS

Final Rejection §112
Filed
Jun 25, 2024
Examiner
NG, HENRY
Art Unit
3741
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Rolls-Royce
OA Round
4 (Final)
63%
Grant Probability
Moderate
5-6
OA Rounds
2y 9m
To Grant
99%
With Interview

Examiner Intelligence

Grants 63% of resolved cases
63%
Career Allow Rate
140 granted / 222 resolved
-6.9% vs TC avg
Strong +58% interview lift
Without
With
+57.9%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
26 currently pending
Career history
248
Total Applications
across all art units

Statute-Specific Performance

§101
0.5%
-39.5% vs TC avg
§103
53.9%
+13.9% vs TC avg
§102
21.6%
-18.4% vs TC avg
§112
19.8%
-20.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 222 resolved cases

Office Action

§112
FINAL 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 . This is the fourth office action on the merits. This office action is in response to the amendment filed on 11/12/2025. Applicant has not made any amendments to the claims. Claims 4, 6-8, and 19 remain withdrawn from further consideration. Claims 1-3, 5, 9-18, and 20 are pending and examined. Drawings The drawings were received on November 12, 2025. These drawings are acceptable. Claim Rejections - 35 USC § 112 The following is a quotation of the first paragraph of 35 U.S.C. 112(a): (a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention. The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112: The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention. Claims 1-3, 5, 9-18, and 20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Regarding claim 1, the limitation “the controller is configured to control the third fueldraulic actuator so that the non-binary position adjustment is based upon calorific value of the fuel” lacks written description because the specification fails to provide enough detail to reasonably conclude that the inventor had possession of the claimed subject matter. Regarding the limitation, the only support provided in the specification is on page 34, lines 30-32: “The hydro-mechanical unit can comprise an actuator configured to regulate the fuel flow to the combustor 16 (e.g. it can be based on parameters including engine thrust demand and fuel calorific value)”. There is no information on how to measure or sense (e.g., with sensors or calorimeters) the calorific value of the fuel. In addition, there is no information on how the valve is regulated based on the calorific value of the fuel. For example, is there a direct or indirect relationship between how much the valve opens and the calorific value of the fuel? Does the valve open if the calorific value of the fuel is below a certain threshold value, or does the valve close if the calorific value is below the threshold? In short, there are no equations or flow charts provided to map the relationship between the position adjustment amount of the valve and the calorific value of the fuel. Furthermore, since a controller is required to perform this limitation, this limitation is considered a computer-implemented functional claim limitation. For computer-implemented functional claim limitations, MPEP 2161.01(I), 6th paragraph, provides the following: “Similarly, original claims may lack written description when the claims define the invention in functional language specifying a desired result but the specification does not sufficiently describe how the function is performed or the result is achieved. For software, this can occur when the algorithm or steps/procedure for performing the computer function are not explained at all or are not explained in sufficient detail (simply restating the function recited in the claim is not necessarily sufficient)”. The specification does not provide any algorithms or steps for performing the computer-implemented function, and the specification merely restates the function recited in the claim (that the fuel flow is based on fuel calorific value). For these reasons, the claim lacks written description. Regarding claim 16, the limitation “controlling the non-binary position adjustment based upon calorific value of the fuel” lacks written description because the specification fails to provide enough detail to reasonably conclude that the inventor had possession of the claimed subject matter. Regarding the limitation, the only support provided in the specification is on page 34, lines 30-32: “The hydro-mechanical unit can comprise an actuator configured to regulate the fuel flow to the combustor 16 (e.g. it can be based on parameters including engine thrust demand and fuel calorific value)”. There is no information on how to measure or sense (e.g., with sensors or calorimeters) the calorific value of the fuel. In addition, there is no information on how the valve is regulated based on the calorific value of the fuel. For example, is there a direct or indirect relationship between how much the valve opens and the calorific value of the fuel? Does the valve open if the calorific value of the fuel is below a certain threshold value, or does the valve close if the calorific value is below the threshold? In short, there are no equations or flow charts provided to map the relationship between the position adjustment amount of the valve and the calorific value of the fuel. Claims 2-3, 5, 9-15, 17-18, and 20 are also rejected because they depend on either claim 1 or 16. 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. Claims 1-3, 5, and 9-15 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 1, the limitation “the controller is configured to control the third fueldraulic actuator so that the non-binary position adjustment is based upon calorific value of the fuel” is indefinite because the claim limitation is a computer-implemented functional claim limitation (due to “the controller is configured”), and as such, the specification must disclose an algorithm for performing the claimed specific computer function, or else the claim is indefinite under 35 U.S.C. 112(b) – see MPEP 2181(II)(B). In this case, the specification does not disclose any algorithms for performing the claimed limitation, thus rendering the limitation indefinite. Furthermore, since this computer-implemented functional claim limitation was rejected under 35 U.S.C. 112(a) for lacking written description, per MPEP 2161.01(I), last paragraph, “A rejection under 35 U.S.C. 112(b) or the second paragraph of pre-AIA 35 U.S.C. 112 must be made in addition to the written description rejection.” Claims 2-3, 5, and 9-15 are also rejected for the same reason as claim 1 because they depend on claim 1. Regarding claim 11, the limitation “a plurality of actuators” is indefinite because the claim depends on claim 1, which recites “fueldraulic actuators” that include “a first fueldraulic actuator”, “a second fueldraulic actuator”, and “a third fueldraulic actuator” (see claim 1, lines 10-12). It is not clear whether “a plurality of actuators” includes the “fueldraulic actuators” of claim 1 or refers to a different set of actuators. For examination purposes, the limitation will be assumed to include the fueldraulic actuators of claim 1. Note that claim 11 further recites “to fueldraulically drive at least ten of the plurality of actuators”. This provides credence that the claim 11 limitation “a plurality of actuators” refers to and includes the “fueldraulic actuators” of claim 1. Claims 12-15 also recite “the plurality of actuators” and are rejected for the same reason as claim 11. Response to Arguments Applicant's arguments filed November 12, 2025 have been fully considered but they are not persuasive. Regarding the 35 U.S.C. § 112(f) Construction (REMARKS, section II), the claim interpretation of “the controller is configured to…” under 35 U.S.C. § 112(f) has been withdrawn. However, the withdrawal of this claim interpretation does not affect the 35 U.S.C. § 112 rejections because the limitation is still considered a computer-implemented functional claim limitation due to “the controller is configured to…”. Regarding Applicant’s argument that “determining calorific value is well known” (REMARKS, pg. 7, 1st paragraph), Applicant provides an example of “a laboratory-based bomb calorimeter”. However, there are no working examples of a calorimeter used on an aircraft to measure the calorific value of fuel in real time. A laboratory-based bomb calorimeter appears to be a device that is used in a laboratory setting, not in an aircraft setting. Applicant further provides a method that involves measuring certain parameters of the fuel, comparing these measurements to expected values, and accessing them against experimental data (such as look-up charts) in order to ascertain calorific value of the fuel. However, this appears to be a much more involved process than simply using a device to measure the calorific value of a fuel, and none of these methods or steps are disclosed in the specification. Applicant’s further arguments (pgs. 7-8 of REMARKS) do not address the lack of written description for the limitation “the controller is configured to control the third fueldraulic actuator so that the non-binary position adjustment is based upon calorific value of the fuel” (claim 1, and similarly for claim 16). Applicant merely provides that the valve position (P) is a function of calorific value (C), i.e., P=f(C) (Declaration ¶ 14). If a person of ordinary skill in the art wished to replicate Applicant’s invention, the person would not know how to program the function into the controller because the function is not disclosed. Providing that P=f(C) is no different from saying y=f(x) (y is a function of x in an xy graph). MPEP 2161.01(I), 6th paragraph, provides the following: “original claims may lack written description when the claims define the invention in functional language specifying a desired result but the specification does not sufficiently describe how the function is performed or the result is achieved. For software, this can occur when the algorithm or steps/procedure for performing the computer function are not explained at all or are not explained in sufficient detail”. In this case, the specification does not describe the function, and does not provide any algorithms or steps for performing the function. Furthermore, since the claims were rejected under 35 U.S.C. 112(a), the claims should also be rejected under 35 U.S.C. 112(b) per MPEP 2161.01(I), last paragraph (“A rejection under 35 U.S.C. 112(b) or the second paragraph of pre-AIA 35 U.S.C. 112 must be made in addition to the written description rejection”). Note that this does not apply to claims 16-18 and 20 because these claims do not recite a controller or a computer. The declaration under 37 CFR 1.132 filed November 12, 2025 is insufficient to overcome the rejection of claims 1-3, 5, 9-18, and 20 based upon 35 U.S.C. § 112 as set forth in the last Office action for the same reasons stated above in the response to Applicant’s arguments. 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 HENRY NG whose telephone number is (571)272-2318. The examiner can normally be reached M-F 9:30 AM - 6:30 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, Devon Kramer can be reached at 571-272-7118. 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. /HENRY NG/Examiner, Art Unit 3741 /DEVON C KRAMER/Supervisory Patent Examiner, Art Unit 3741
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Prosecution Timeline

Jun 25, 2024
Application Filed
Oct 11, 2024
Examiner Interview (Telephonic)
Oct 17, 2024
Non-Final Rejection — §112
Jan 16, 2025
Response Filed
Jan 28, 2025
Final Rejection — §112
Mar 18, 2025
Response after Non-Final Action
Apr 10, 2025
Request for Continued Examination
Apr 14, 2025
Response after Non-Final Action
Aug 06, 2025
Non-Final Rejection — §112
Nov 12, 2025
Response Filed
Dec 09, 2025
Final Rejection — §112
Feb 26, 2026
Examiner Interview Summary
Feb 26, 2026
Applicant Interview (Telephonic)

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Study what changed to get past this examiner. Based on 5 most recent grants.

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Prosecution Projections

5-6
Expected OA Rounds
63%
Grant Probability
99%
With Interview (+57.9%)
2y 9m
Median Time to Grant
High
PTA Risk
Based on 222 resolved cases by this examiner. Grant probability derived from career allow rate.

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