Prosecution Insights
Last updated: April 19, 2026
Application No. 19/172,204

ROTARY ENGINE, PARTS THEREOF, AND METHODS

Non-Final OA §102§103
Filed
Apr 07, 2025
Examiner
NGUYEN, NGOC T
Art Unit
3799
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Astron Aerospace LLC
OA Round
1 (Non-Final)
83%
Grant Probability
Favorable
1-2
OA Rounds
2y 2m
To Grant
99%
With Interview

Examiner Intelligence

Grants 83% — above average
83%
Career Allow Rate
407 granted / 490 resolved
+13.1% vs TC avg
Strong +20% interview lift
Without
With
+19.9%
Interview Lift
resolved cases with interview
Typical timeline
2y 2m
Avg Prosecution
16 currently pending
Career history
506
Total Applications
across all art units

Statute-Specific Performance

§101
2.4%
-37.6% vs TC avg
§103
32.9%
-7.1% vs TC avg
§102
26.5%
-13.5% vs TC avg
§112
32.9%
-7.1% vs TC avg
Black line = Tech Center average estimate • Based on career data from 490 resolved cases

Office Action

§102 §103
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 . Claim Interpretation 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: “compression assembly” and “combustion assembly” in claims 1-3, 8, 11-13, 18 and 20; and “first expansion member” in claims 7 and 17. 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 § 102 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 (i.e., changing from AIA to pre-AIA ) 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. 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)(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(s) 1, 2, 8, 11, 12, and 18 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by US 3782340 A to Nam. In reference to independent claims 1 and 11, Nam discloses: An internal combustion engine (not numbered, see Abstract) comprising: a compression assembly (compression cylinder housing 1 and compression cylinder 6) that is configured to compress working fluid; a combustion assembly (combustion cylinder housing 2 and combustion cylinder 14) that is configured to generate power from expansion of the working fluid; and a channel (ignition chamber 18) connecting the compression assembly to the combustion assembly (see Fig. 2), said channel in fluid communication with the combustion assembly during a combustion process (see col. 4 at lines 25-55), wherein the combustion process comprises ignition of a charge comprising at least a first portion of compressed working fluid, thereby thermally expanding the first portion of the compressed working fluid (see col. 4 at lines 25-55), and wherein at least a portion of the thermal expansion of the first portion of the compressed working fluid occurs in the channel (see col. 4 at lines 25-55). In reference to dependent claims 2 and 12, Nam further discloses: a rotor of said compression assembly and/or a rotor of said combustion assembly controls the fluid flow out of the compression assembly (see col. 4 at lines 25-55) and/or into the combustion assembly (see col. 5 at lines 19-35). In reference to dependent claims 8 and 18, Nam further discloses: a combination of power and/or isolator rotors (rotors 8 and 11) from said combustion and/or compression assemblies is used to control the fluid flow out of said compression assembly and/or into said combustion assembly (see col. 4 at lines 25-55 and col. 5 at lines 19-35). 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. Claim(s) 5 and 15 is/are rejected under 35 U.S.C. 103 as being unpatentable over Nam. Nam is silent regarding exhaust being recycled into an intake of the engine. However, exhaust gas recirculation (EGR) is well-known in internal combustion engines. Thus, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the engine of Nam to include an EGR system to recirculate exhaust gases to the engine’s intake in order to reduce exhaust emissions and improve engine efficiency and fuel economy as is well-known in the art. Allowable Subject Matter Claims 3, 4, 6, 7, 9, 10, 13, 14, 16, 17, and 19 are objected to as being dependent upon a rejected base claim, but would be allowable if rewritten in independent form including all of the limitations of the base claim and any intervening claims. The following is a statement of reasons for the indication of allowable subject matter: Regarding claims 3 and 13, the prior art of record does not disclose or teach a rotor of the combustion assembly controls the fluid flow into the compression assembly. Regarding claims 4 and 14, the prior art of record does not disclose or teach using steam the compression and/or combustion assemblies for sealing and/or cooling purposes. Regarding claims 6 and 16, the usage of hydrogen as fuel in rotary engines are known. However, the prior art of record does not disclose or teach an electrolyzer that recycles exhaust gases back to an intake to produce hydrogen from exhaust vapors to be used as fuel for the engine. Regarding claims 7 and 17, the prior art of record does not disclose or teach Astron Aerospace’s YouTube video titled "Introducing the Omega 1. A revolutionary engine." (cited in the Non-Final Rejection of the US Application 18/587,705 mailed August 13, 2024) discloses an internal combustion engine having a compression assembly, a combustion assembly and a channel connecting the two assemblies. However, at 6:22 (also at 3:12) the video shows that ignition and thus expansion occurs in the combustion chamber and NOT at least in part in the channel. Thus, even though the video shows a cylindrical power rotor of the combustion housing as recited in claims 7 and 17, Astron’s video does not meet the requirements of the recitations of independent claims 1 and 11. Regarding claims 9 and 19, the prior art of record does not disclose or teach the engine enabling the ability to independently configure intake compression to power exhaust ratios during operation of the engine. Regarding claim 10, the prior art does not disclose or teach water and/or other fluid is injected into an intake of the engine to help reduce temperatures during the combustion process. Claim 20 is allowed. The following is an examiner’s statement of reasons for allowance: In reference to independent claim 20, Astron’s video discloses a method including expanding within a combustion assembly of the engine a first amount of working fluid during a first power stroke of the engine, the combustion assembly defining a combustion chamber (see video at 3:12 and Fig. 5); compressing within a compression assembly of the engine a second amount of working fluid during a first compression stroke of the engine, wherein the first power stroke of the engine is contemporaneous with the first compression stroke of the engine such that the engine has a first intake compression to power exhaust ratio (see video at 3:12 and also Fig. 5); flowing at least a portion of the second amount of the working fluid into a channel, the channel being in fluid communication with the combustion chamber during a combustion process of the combustion assembly (see video at 6:22, which shows the mixture of air and fuel being ignited and expanded in the combustion chamber and the port is closed but the channel is in communication with combustion chamber). However, Astron’s video shows (at 6:22 and 3:12) that expansion occurs within the combustion chamber and not at least partially through said channel during the combustion process. Moreover, the engine of Nam (as applied in the rejections of claims 1 and 11 above) is operated such that at least a portion of the thermal expansion of the first portion of the compressed working fluid occurs in the channel (see col. 4 at lines 25-55). However, Nam does not disclose or teach the first power stroke of the engine is contemporaneous with the first compression stroke of the engine such that the engine has a first intake compression to power exhaust ratio. Any comments considered necessary by applicant must be submitted no later than the payment of the issue fee and, to avoid processing delays, should preferably accompany the issue fee. Such submissions should be clearly labeled “Comments on Statement of Reasons for Allowance.” Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to Ngoc T Nguyen whose telephone number is (571)272-7176. The examiner can normally be reached M-F 9:00 am - 5:00 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, 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. /NGOC T NGUYEN/Primary Examiner, Art Unit 3799
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Prosecution Timeline

Apr 07, 2025
Application Filed
Jan 10, 2026
Non-Final Rejection — §102, §103 (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
83%
Grant Probability
99%
With Interview (+19.9%)
2y 2m
Median Time to Grant
Low
PTA Risk
Based on 490 resolved cases by this examiner. Grant probability derived from career allow rate.

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