Prosecution Insights
Last updated: April 19, 2026
Application No. 18/240,399

CASCADING STACK ELECTROCHEMICAL FUEL CELL

Non-Final OA §102§112
Filed
Aug 31, 2023
Examiner
EOFF, ANCA
Art Unit
1722
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Infinity Fuel Cell And Hydrogen Inc.
OA Round
1 (Non-Final)
80%
Grant Probability
Favorable
1-2
OA Rounds
2y 10m
To Grant
91%
With Interview

Examiner Intelligence

Grants 80% — above average
80%
Career Allow Rate
982 granted / 1230 resolved
+14.8% vs TC avg
Moderate +11% lift
Without
With
+11.3%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
48 currently pending
Career history
1278
Total Applications
across all art units

Statute-Specific Performance

§101
0.2%
-39.8% vs TC avg
§103
47.1%
+7.1% vs TC avg
§102
20.0%
-20.0% vs TC avg
§112
20.0%
-20.0% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1230 resolved cases

Office Action

§102 §112
DETAILED ACTION The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA . Election/Restrictions Applicant's election with traverse of Group I (claims 1-7 and 21) in the reply filed on December 22, 2025 is acknowledged. The traversal is on the ground that searching for the Groups I-III would not be a serious burden. This is not found persuasive because the features of the fuel cells I and III are different: the fuel cell of Group III requires a humidifier-degasser comprising at least one hydrogen removal section which is not required in Group I, and the method in Group II requires a hydrogen removal cell which is not required in the fuel cell of Group I. Therefore, claims 1-7 and 14-22 are pending, with claims 14-20 and 22 withdrawn from consideration as being directed to non-elected inventions. The requirement is still deemed proper and is therefore made FINAL. Specification The disclosure is objected to because of the following informalities: In par.0022 and par.0027 the limitation “product water passage” should be corrected to read “product water flow passage”. The amendment is needed in order to maintain language consistency in the specification. Appropriate correction is required. Claim Objections Claims 1-7 are objected to because of the following informalities: The examiner suggests that the limitation “at least one degasification section coupled via an MEA material to a reactant and a product water upstream of at least one humidifier section” in claim 1 is amended to read “at least one degasification section coupled upstream of at least one humidifier section, wherein the at least one degasification section comprises a membrane electrode assembly (MEA) between a reactant flow passage and a product water flow passage” (see par.0020 and par.0023 of the specification). The amendment enhances the clarity of the claim. The limitation “product water passage” in claim 3, line 9 should be amended to read “product water flow passage”. The amendment is needed in order to maintain language consistency in claim 3. Claims 2 and 4-7 are objected as being dependent on the objected claim 1. Appropriate correction is required. 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 7 is 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. Claim 7 recites the limitation "said at least one catalyst" in line 2. There is insufficient antecedent basis for this limitation in the claim. Therefore, it is not clear what is the joint inventor claiming as the invention in claim 7 of the instant application. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraph of 35 U.S.C. 102 that forms the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claim 21 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by McElroy et al. (US 2014/0072889). McElroy et al. teach the cell fuel system 100A of fig.1: PNG media_image1.png 288 516 media_image1.png Greyscale . The fuel cell system (100A) comprises the stack (106)(par.0012), which may comprise cascading fuel cell stacks wherein the effluent of a plurality of stacks may be routed to another plurality of stacks(par.0060). This equivalent to the “series of cascaded cell stacks” in claim 21. The fuel cell system (100A) comprises the hydrogen pumps (135) fed by the fuel exhaust stream (110), and the hydrogen pumps (135) work as hydrogen concentrator (par.0016). Additionally, par.0024 of the specification of the instant application defines a hydrogen pump as inert concentrator. Fig. 1 clearly shows that the hydrogen pumps (135) are placed downstream from the stack (106) proximate a stack vent for the fuel exhaust stream (110) (see also par.0016). The hydrogen pumps (135) meet the limitations for “one inert concentrator cell coupled downstream from said cell stacks proximate a stack vent” in claim 21. Therefore, the fuel cell system (100A) of McElroy et al. anticipates the fuel cell in claim 21. Allowable Subject Matter Claims 1-6 would be allowable if rewritten or amended to overcome the objections set forth in this Office action. JP 2002-542592 A (with attached machine translation) teach the fuel cell system of fig.4a: PNG media_image2.png 722 512 media_image2.png Greyscale . Refrigerant and oxidizing air passes through the degassing portion (51) of the degassing device (45) so as to be countercurrent. Mass transfer in the degassing section (51) causes a significant portion of the gas dissolved in the refrigerant to diffuse into the oxidant stream, thereby removing most of the dissolved gas from the refrigerant. This results in a refrigerant having acceptable conductivity and dissolved gas content. The oxidizing air is humidified, it is pumped out of the degasser (45) and supplied to the cathode of the fuel cell device (11)(see page 8 of the attached machine translation). Takahiro et al. (JP 2007-193962 A, with attached machine translation) teach the fuel cell power generator of fig.1: PNG media_image3.png 266 364 media_image3.png Greyscale . The fuel cell power generator comprises impurity gas removing means (72) and a humidifier (8) (see page 7 of the attached machine translation). However, the references above do not teach the fuel cell of claim 1. There are no prior art teachings that would motivate one of ordinary skill to modify any of the references above and obtain the fuel cell in claim 1 of the instant application. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to ANCA EOFF whose telephone number is (571)272-9810. The examiner can normally be reached Mon-Fri 10am-6:30pm. 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, Niki Bakhtiari can be reached at (571)272-3433. 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. /ANCA EOFF/ Primary Examiner, Art Unit 1722
Read full office action

Prosecution Timeline

Aug 31, 2023
Application Filed
Mar 08, 2026
Non-Final Rejection — §102, §112 (current)

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

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Prosecution Projections

1-2
Expected OA Rounds
80%
Grant Probability
91%
With Interview (+11.3%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 1230 resolved cases by this examiner. Grant probability derived from career allow rate.

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