Prosecution Insights
Last updated: April 19, 2026
Application No. 18/655,109

FUEL SUPPLY DEVICE FOR SUPPLYING A FUEL AND INTERNAL COMBUSTION ENGINE

Non-Final OA §112
Filed
May 03, 2024
Examiner
STANEK, KELSEY L
Art Unit
3741
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Liebherr Machines Bulle SA
OA Round
3 (Non-Final)
81%
Grant Probability
Favorable
3-4
OA Rounds
2y 8m
To Grant
96%
With Interview

Examiner Intelligence

Grants 81% — above average
81%
Career Allow Rate
519 granted / 644 resolved
+10.6% vs TC avg
Strong +16% interview lift
Without
With
+15.9%
Interview Lift
resolved cases with interview
Typical timeline
2y 8m
Avg Prosecution
18 currently pending
Career history
662
Total Applications
across all art units

Statute-Specific Performance

§101
1.8%
-38.2% vs TC avg
§103
41.1%
+1.1% vs TC avg
§102
26.4%
-13.6% vs TC avg
§112
28.8%
-11.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 644 resolved cases

Office Action

§112
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 . Continued Examination Under 37 CFR 1.114 A request for continued examination under 37 CFR 1.114, including the fee set forth in 37 CFR 1.17(e), was filed in this application after final rejection. Since this application is eligible for continued examination under 37 CFR 1.114, and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114. Applicant's submission filed on 01/23/2026 has been entered. Claim Rejections - 35 USC § 112 3. 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 1-17 and 21-23 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 Lines 14-17 recite the limitation “the fuel supply device is controllable to allow a supply of the secondary fuel into the main combustion chamber and into the prechamber simultaneously with supplying the primary fuel to the main combustion chamber, the primary fuel being N H 3 , and the secondary fuel being H 2 ”. This limitation is not disclosed within the specification. Therefore, claim 1 fails to comply with the written description requirement. Regarding Claims 2-17 Claims 2-17 are rejected insofar as they are dependent upon a rejected base claim. Regarding Claim 21 Lines 14-17 recite the limitation “the fuel supply device is controllable to allow a supply of the secondary fuel into the main combustion chamber and into the prechamber simultaneously with supplying the primary fuel to the main combustion chamber, the primary fuel being N H 3 , and the secondary fuel being H 2 ”. This limitation is not disclosed within the specification. Therefore, claim 21 fails to comply with the written description requirement. Regarding Claim 22 Lines 14-17 recite the limitation “the fuel supply device is controllable to allow a supply of the secondary fuel into the main combustion chamber and into the prechamber simultaneously with supplying the primary fuel to the main combustion chamber, the primary fuel being N H 3 , and the secondary fuel being H 2 ”. This limitation is not disclosed within the specification. Therefore, claim 22 fails to comply with the written description requirement. Regarding Claim 23 Claim 23 is rejected insofar as they are dependent upon a rejected base claim. Response to Arguments With regards to the Applicant's argument that support for the features of the 35 U.S.C. 112(a) rejection are found at least in paragraphs [0022], [0024], [0035], and [0038], the Examiner is unconvinced. The Applicant argues that paragraph [0022] shows that ammonia is supported as the primary fuel and molecular hydrogen is supported as the secondary fuel. The Examiner argues that while paragraphs [0022], [0024], [0035], and [0038] may disclose ammonia and hydrogen as the primary and secondary fuels, the paragraphs do not disclose "the fuel supply device is controllable to allow a supply of the secondary fuel into the main combustion chamber and into the prechamber simultaneously with supplying the primary fuel into the main combustion chamber" as is required by claim 1. This simultaneous supply of the primary and secondary fuels is not disclosed in the specification. The Applicant argues that paragraph [0011] discloses a flushed prechamber, wherein secondary fule is injected into the prechamber and is then injected into the main combustion chamber via the prechamber. Therefore, the secondary fuel is injected into the prechamber and the main chamber simultaneously. The Examiner is not convinced. The plain meaning of the term “simultaneous” is occurring at the same time. If the secondary fuel is first injected into the prechamber to then be injected into the main combustion chamber, it is not being supplied at the same time. The Applicant argues that paragraph [0012] discloses that the primary fuel is mixed with the secondary fuel and then combusted in the combustion chamber or the main chamber. The Examiner argues that this does not teach supplying the secondary fuel into the main combustion chamber and into the prechamber simultaneously with supplying the primary fuel into the main combustion chamber as claimed. The Applicant also argues with regard to paragraph [0012] that a higher proportion of secondary fuel is contained in the prechamber than in the main combustion chamber and therefore, the secondary fuel is supplied to both the prechamber and the main chamber simultaneously. The Examiner not convinced. Paragraph [0012] does not disclose when the secondary fuel is being supplied to both the prechamber and the main chamber and therefore one cannot assume that they occur simultaneously. The Applicant argues that paragraph [0008] discloses the secondary fuel simultaneously supplied to the main combustion chamber as well as the prechamber because paragraph [0008] discloses that supply of secondary fuel to the prechamber optimizes combustion and makes primary fuel ignition reliable. The Examiner is not convinced. While paragraph [0008] discloses a benefit to injection of secondary fuel into the prechamber it does not disclose the simultaneous supply of secondary fuel to the prechamber and main combustion chamber, and primary fuel to the main combustion chamber. The Applicant argues that paragraph [0054] inherently discloses simultaneous hydrogen supply to the main combustion chamber and the prechamber is possible. The Examiner is not convinced. Paragraph [0054] states “if, however, only the prechambers are supplied with the secondary fuel while the combustion chambers are only supplied with the primary fuel”. The Examiner is not convinced that stating an embodiment in which “only the prechambers are supplied with the secondary fuel while the combustion chambers are only supplied with the primary fuel” implies that it is inherent that an embodiment exists providing “the secondary fuel into the main combustion chamber and into the prechamber simultaneously with supplying the primary fuel into the main combustion chamber”. Claims 1-17 remain rejected under 35 U.S.C. 112(a) as failing to comply with the written description requirement. New claims 21-23 include the same language as recited in claim 1 and therefore are also rejected under 35 U.S.C. 112(a). Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to KELSEY L STANEK whose telephone number is (571)272-3565. The examiner can normally be reached Mon - Fri 8:30am-3:00pm. 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, MARK LAURENZI can be reached at 571-270-7878. 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. /K.L.S/Examiner, Art Unit 3746 2/20/2026 /MARK A LAURENZI/Supervisory Patent Examiner, Art Unit 3746 2/23/2026
Read full office action

Prosecution Timeline

May 03, 2024
Application Filed
Oct 16, 2024
Examiner Interview (Telephonic)
Oct 17, 2024
Examiner Interview Summary
Feb 28, 2025
Non-Final Rejection — §112
Jul 07, 2025
Response Filed
Sep 19, 2025
Final Rejection — §112
Nov 24, 2025
Response after Non-Final Action
Jan 23, 2026
Request for Continued Examination
Feb 18, 2026
Response after Non-Final Action
Feb 20, 2026
Non-Final Rejection — §112 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12601339
AIR COMPRESSOR
2y 5m to grant Granted Apr 14, 2026
Patent 12590554
Catalytic Converter for a Motor Vehicle, as Well as a Motor Vehicle
2y 5m to grant Granted Mar 31, 2026
Patent 12577894
VARIABLE CAMSHAFT TIMING ASSEMBLY WITH DEFORMABLE EXTENSION
2y 5m to grant Granted Mar 17, 2026
Patent 12577946
Proportional Additive Dosing Pump with Bidirectional Rolling Diaphragm
2y 5m to grant Granted Mar 17, 2026
Patent 12577900
RECOVERY OF ENERGY
2y 5m to grant Granted Mar 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

3-4
Expected OA Rounds
81%
Grant Probability
96%
With Interview (+15.9%)
2y 8m
Median Time to Grant
High
PTA Risk
Based on 644 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month