Prosecution Insights
Last updated: April 19, 2026
Application No. 18/673,437

ENGINE OIL SYSTEM FOR AN AIRCRAFT PROPULSION SYSTEM

Non-Final OA §102§103§112
Filed
May 24, 2024
Examiner
BUSE, MARK KENNETH
Art Unit
3654
Tech Center
3600 — Transportation & Electronic Commerce
Assignee
Pratt & Whitney Canada Corp.
OA Round
1 (Non-Final)
77%
Grant Probability
Favorable
1-2
OA Rounds
2y 10m
To Grant
86%
With Interview

Examiner Intelligence

Grants 77% — above average
77%
Career Allow Rate
549 granted / 712 resolved
+25.1% vs TC avg
Moderate +9% lift
Without
With
+9.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 10m
Avg Prosecution
20 currently pending
Career history
732
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
41.5%
+1.5% vs TC avg
§102
24.7%
-15.3% vs TC avg
§112
29.5%
-10.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 712 resolved cases

Office Action

§102 §103 §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 . 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 at least one bypass valve includes an anti-rotation feature”. It is unclear what portion of the bypass valve includes an anti-rotation feature. Is it the housing in relation to the manifold body? Is it the valve member in relation to the housing? Is it the valve positioning assembly in relation to the housing? Also, what claimed structure would require an anti-rotation feature Claim 14 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 14 recites “the at least one bypass valve includes an anti-rotation feature,…”. It is unclear what claimed structure requires an anti-rotation feature? Claim Rejections - 35 USC § 102 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. (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claims 1, 4, 5, 8, 9, 11-13 and 15-17 are rejected under 35 U.S.C. 102(a)(1)(a)(2) as being anticipated by Kapur, U.S. Patent Publication 2003/0127384 . As per claims 1 and 17, Kapur discloses an engine oil system for an aircraft propulsion system (paras [0001, 0002]), the engine oil system comprising: a filter assembly (9) including a filter manifold (fig. E-1) and at least one bypass valve (30, 21, 13) [bypass valve, tubular extension, cover]; the filter manifold (fig. E-1) including a manifold body (fig. E-1), an oil inlet (fig. E-1), and an oil outlet (fig. E-1), the manifold body forming an inlet passage (3), an outlet passage (4), and a valve cavity (fig. E-1), the inlet passage disposed at the oil inlet, the outlet passage disposed at the oil outlet, the valve cavity (fig. E-1) disposed at the outlet passage, the manifold body including a wall portion (fig. E-1) (wall portion includes all wall surfaces of module housing 2 and tubular extension 21) extending between and to an inlet passage side surface (fig. E-1) and an outlet passage side surface (fig. E-1), the inlet passage side surface forming the inlet passage, the outlet passage side surface forming the outlet passage, the wall portion forming a bypass channel (10) extending between and to the inlet passage side surface and the outlet passage side surface; and the at least one bypass valve (30, 21, 13) including a housing (fig. E-1), a valve member (fig. E-1), and a valve positioning assembly (18), the housing (fig. E-1) disposed on the manifold body within the valve cavity (fig. E-1), the housing (fig. E-1) extending circumferentially about a valve axis to form a valve chamber, the valve member (fig. E-1) positioned within the valve chamber, the valve member including a valve body forming a valve plug end (fig. E-1), the valve member positionable along the valve axis in a closed position (fig. 1) and an open position (fig. 2), in the closed position of the valve member the valve plug end is seated on the wall portion obstructing the bypass channel (10), in the open position of the valve member (fig. E-1) the valve plug end (fig. E-1) is separated from the wall portion, and the valve position assembly (18) disposed at the housing (fig. E-1), the valve position assembly (18) configured to control a position of the valve member in the closed position (fig. 1) or the open position (fig. 2). PNG media_image1.png 687 753 media_image1.png Greyscale As per claims 4 and 12, Kapur as set forth above, discloses the inlet passage (3) extends along an inlet passage centerline axis, the outlet passage (4) extends along an outlet passage centerline axis, and the inlet passage centerline axis is substantially parallel to the outlet passage centerline axis (fig. 1). As per claims 5 and 13, Kapur as set forth above, discloses the inlet passage (3) extends along an inlet passage centerline axis, the outlet passage (4) extends along an outlet passage centerline axis, and the valve axis is substantially orthogonal to the inlet passage centerline axis and the outlet passage centerline axis (fig. 1). As per claims 8 and 15, Kapur as set forth above, discloses the valve body (30) (fig. E-1, valve plug end) extends longitudinally between and to a first longitudinal end and a second longitudinal end, the valve body includes a first semi-circular end portion at the first longitudinal end, a second semi-circular end portion at the second longitudinal end, and an intermediate portion connecting the first semi-circular end portion and the second semi-circular end portion. There is no claimed feature that defines a delineation between the first and second semi-circular portions, therefore the intermediate portion can be defined as any portion between the first and second ends. As per claims 9 and 16, Kapur as set forth above, discloses the first semi-circular end portion and the second semi-circular end portion have a diameter, the intermediate portion has a length extending between and to the first semi-circular end portion and the second semi-circular end portion, and a ratio of the length to the diameter is less than or equal to 1.75. There is no claimed feature that defines a delineation between the first and second semi-circular portions, therefore the intermediate portion can be defined as any portion between the first and second ends. In this case, the intermediate portion has 0 length. Therefore, the ratio of the length to the diameter is 0/diameter of semi-circular end portion = 0. Zero is less than 1.75 As per claim 11, Kapur discloses an engine oil system for an aircraft propulsion system (paras [0001, 0002]), the engine oil system comprising: a pump (abstract) configured to circulate oil along an oil flow path through one or more engine oil loads (para [0002]); and a filter assembly (9) forming a portion of the oil flow path (paras [0002-0004]), the filter assembly including a filter manifold (fig. E-1), a filter (12), and at least one bypass valve (30, 21, 13) [bypass valve, tubular extension, cover]; the filter manifold (fig. E-1) including a manifold body (fig. E-1), an oil inlet (fig. E-1), and an oil outlet (fig. E-1), the manifold body forming an inlet passage (3), an outlet passage (4), and a valve cavity (fig. E-1), the inlet passage extending between and to the oil inlet and the filter, the outlet passage extending between and to the oil outlet and the filter, the manifold body including a wall portion (fig. E-1) (wall portion includes all wall surfaces of module housing 2 and tubular extension 21) forming the inlet passage (3) and the outlet passage (4), the wall portion forming a bypass channel (10) extending between and to the inlet passage (3)and the outlet passage (4); and the at least one bypass valve (30, 21, 13) including a housing (fig. E-1), a valve member (fig. E-1), and a valve positioning assembly (18), the housing (fig. E-1) mounted on the manifold body, the housing extending circumferentially about a valve axis to form a valve chamber, the valve member (fig. E-1) positioned within the valve chamber, the valve member including a valve body forming a valve plug end (fig. E-1), the valve member translatable along the valve axis in a closed position (fig. 1) and an open position (fig. 2), in the closed position of the valve member the valve plug end is seated on the wall portion obstructing the bypass channel (10), in the open position of the valve member (fig. E-1) the valve plug end (fig. E-1) is separated from the wall portion, and the valve position assembly (18) disposed at the housing (fig. E-1), the valve position assembly (18) including a spring (18) biasing the valve member (fig. E-1) in the closed position (fig. 1). 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. Claims 2, 3 and17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Kapur, U.S. Patent Publication 2003/0127384 in view of Kane, U.S. Patent 7,290,562. As per claims 2 and 17, Kapur as set for above, Kapur does not disclose the valve member further includes a piston, stem and a valve body, the piston is disposed within the valve chamber, and the stem extends along the valve axis between and to the piston and the valve body; the valve body forming a valve plug end, the valve member positionable along the valve axis in a closed position and an open position, in the closed position of the valve member the valve plug end is seated on the wall portion obstructing the bypass channel, in the open position of the valve member the valve plug end is separated from the wall portion. However, Kane in his Non-return Valve invention teaches the use of a non-return valve including a piston (4) (fig. 2), a stem (portion of 4 with bores 52) and a valve body (56). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the invention of Kapur with a plastics based non-return return valve, as taught by Kane, for the purpose of increasing response times due to a lighter weight piston and/or reduced cost. As per claims 3 and 18, Kapur and Kane as set forth above, Kapur as modified, Kane discloses the valve position assembly (fig. 2, Kane) includes a spring (16) disposed within the valve chamber (24, Kane) [reception bore], the spring (16) is positioned between and contacting the housing (22) (spring cup 22 is part of the valve chamber and housing) and the piston (4), and the spring biases the valve member in the closed position (fig. 2). As per claim 19, Kapur and Kane as set forth above, Kane discloses the valve body (56) (fig. 2) extends longitudinally between and to a first longitudinal end and a second longitudinal end, the valve body includes a first semi-circular end portion at the first longitudinal end, a second semi-circular end portion at the second longitudinal end, and an intermediate portion connecting the first semi-circular end portion and the second semi-circular end portion. There is no claimed feature that defines a delineation between the first and second semi-circular portions, therefore the intermediate portion can be defined as any portion between the first and second ends. As per claim 20, Kapur and Kane as set forth above, Kane discloses the first semi-circular end portion and the second semi-circular end portion have a diameter, the intermediate portion has a length extending between and to the first semi-circular end portion and the second semi-circular end portion, and a ratio of the length to the diameter is less than or equal to 1.75. There is no claimed feature that defines a delineation between the first and second semi-circular portions, therefore the intermediate portion can be defined as any portion between the first and second ends. In this case, the intermediate portion has 0 length. Therefore, the ratio of the length to the diameter is 0/diameter of semi-circular end portion = 0. Zero is less than 1.75 Claim 6 is rejected under 35 U.S.C. 103 as being unpatentable over Kapur, U.S. Patent Publication 2003/0127384 in view of Egan, U.S. Patent 4,512,299. As per claim 6, Kapur as set forth above, does not disclose the at least one bypass valve includes a plurality of bypass valves. However, Egan et al. in their Automotive Engine with Improved Multifilter Lubrication System invention teaches the use of multiple oil filter assemblies (fig) (col. 2, lines 14-59). Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the engine oil system of Kapur with multiple filter modules (each containing a bypass valve), as taught by Egan et al., for the purpose of filtering different oil flows with varying micron filter media for optimized performance with more critical loads in the lubrication circuit (col. 2, lines 14-59). Claims 7 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over Kapur, U.S. Patent Publication 2003/0127384. As per claims 7 and 14, Kapur as set forth above, discloses the claimed invention except for the at least one bypass valve includes an anti-rotation feature, the anti-rotation feature includes a slot and a protrusion disposed in the slot, the slot is formed by the valve member and the protrusion is formed by the housing. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to ensure features of a bypass valve requiring orientation use an anti-rotation feature since examiner takes Official Notice that the use of keys or cooperating tabs/protrusions, geometric shapes, or other mechanisms to resist rotational motion are well known in the art. Allowable Subject Matter Claim 10 is 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: the prior art of record fails teach or suggest An engine oil system for an aircraft propulsion system, the engine oil system comprising: a filter assembly including a filter manifold and at least one bypass valve; the filter manifold including a manifold body, an oil inlet, and an oil outlet, the manifold body forming an inlet passage, an outlet passage, and a valve cavity, the inlet passage disposed at the oil inlet, the outlet passage disposed at the oil outlet, the valve cavity disposed at the outlet passage, the manifold body including a wall portion extending between and to an inlet passage side surface and an outlet passage side surface, the inlet passage side surface forming the inlet passage, the outlet passage side surface forming the outlet passage, the wall portion forming a bypass channel extending between and to the inlet passage side surface and the outlet passage side surface; and the at least one bypass valve including a housing, a valve member, and a valve positioning assembly, the housing disposed on the manifold body within the valve cavity, the housing extending circumferentially about a valve axis to form a valve chamber, the valve member positioned within the valve chamber, the valve member including a valve body forming a valve plug end, the valve member positionable along the valve axis in a closed position and an open position, in the closed position of the valve member the valve plug end is seated on the wall portion obstructing the bypass channel, in the open position of the valve member the valve plug end is separated from the wall portion, and the valve position assembly disposed at the housing, the valve position assembly configured to control a position of the valve member in the closed position or the open position; wherein the valve body extends longitudinally between and to a first longitudinal end and a second longitudinal end, the valve body includes a first semi-circular end portion at the first longitudinal end, a second semi-circular end portion at the second longitudinal end, and an intermediate portion connecting the first semi-circular end portion and the second semi-circular end portion; wherein the first semi-circular end portion and the second semi-circular end portion have a diameter, the intermediate portion has a length extending between and to the first semi-circular end portion and the second semi-circular end portion, and a ratio of the length to the diameter is between 0.25 and 1.75. Any inquiry concerning this communication or earlier communications from the examiner should be directed to MARK KENNETH BUSE whose telephone number is (571)270-3139. The examiner can normally be reached 8:00 am to 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, Victoria Augustine can be reached at 313 446-4858. 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. /M.K.B/Examiner, Art Unit 3654 /ANNA M MOMPER/Supervisory Patent Examiner, Art Unit 3619
Read full office action

Prosecution Timeline

May 24, 2024
Application Filed
Nov 15, 2025
Non-Final Rejection — §102, §103, §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
77%
Grant Probability
86%
With Interview (+9.2%)
2y 10m
Median Time to Grant
Low
PTA Risk
Based on 712 resolved cases by this examiner. Grant probability derived from career allow rate.

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