Prosecution Insights
Last updated: April 19, 2026
Application No. 18/502,598

LIQUID FILTER ELEMENT AND ASSEMBLY

Non-Final OA §102§103
Filed
Nov 06, 2023
Examiner
KIM, SUN U
Art Unit
1777
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Baldwin Filters Inc.
OA Round
1 (Non-Final)
78%
Grant Probability
Favorable
1-2
OA Rounds
2y 11m
To Grant
90%
With Interview

Examiner Intelligence

Grants 78% — above average
78%
Career Allow Rate
747 granted / 954 resolved
+13.3% vs TC avg
Moderate +11% lift
Without
With
+11.2%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
31 currently pending
Career history
985
Total Applications
across all art units

Statute-Specific Performance

§101
0.7%
-39.3% vs TC avg
§103
47.2%
+7.2% vs TC avg
§102
21.6%
-18.4% vs TC avg
§112
17.5%
-22.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 954 resolved cases

Office Action

§102 §103
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. Election/Restrictions Applicant's election with traverse of Species 1 (claims 2-9, 26-28) in the reply filed on 2/26/2026 is acknowledged. The traversal is on the ground(s) that Species 1-4 are not mutually exclusive. This is not found persuasive because the cooperating geometry including the axial retention mechanism having the particular combination in Species 1-4 according to Figure 2-4. 5-6, 7-10 and 11-16 respectively as described in the restriction mailed 1/23/2026 are mutually exclusive. The requirement is still deemed proper and is therefore made FINAL. Claims 10-25 and 29-36 are withdrawn from further consideration pursuant to 37 CFR 1.142(b), as being drawn to a nonelected species, there being no allowable generic or linking claim. Applicant timely traversed the restriction (election) requirement in the reply filed on 2/26/2026. 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 1-3, 5 and 8-9 are rejected under 35 U.S.C. 102(a)(1)/102(a)(2) as being anticipated by US 2018/0193780 A1 to Harrelson et al. (hereinafter “Harrelson”). Regarding claim 1, Harrelson disclose a filter cartridge ( filter: 100) comprising: a canister ( housing: 300) configured to hold a filter element ( filter media: 16 ) , the canister (300) having a canister body with an open end (304) and an end closure ( cover plate 200) , the end closure having: a central annular element locating feature (axial collar 219 ) ; and an annular frame portion (ledge 216) circumscribing the central annular element locating feature (216) ; wherein the canister body and end closure (200) have cooperating geometry for retaining the end closure (200) to the open end (304) of the canister (300) , the cooperating geometry including: an axial retention mechanism (engagement tabs 220) for maintaining an attachment between the canister (300) and the end closure (200) , the axial retention mechanism configured to maintain the attachment solely via mechanical interference (see Figures 1-4; paragraphs [0025]-[0036]) . Regarding claim 2, Harrelson disclose that the axial retention mechanism comprises: an internal annular rib (316) circumscribing an inner surface of the canister (300) , proximate the open end (304) ; and an external annular rib (220) circumscribing an outer surface of the flexible portion of the end closure (200) , the external annular rib (220) of the flexible portion of the end closure configured and arranged to engage the internal annular rib (316) of the canister when the end closure (200) is attached to the open end (304) of the canister (300) (see Figures 1, 4) . Regarding claim 3, Harrelson disclose that the internal annular rib (316) extends continuously around the inner surface of the canister (300) (see Figures 1, 4) . Regarding claim 5, Harrelson disclose that the external annular rib (220) extends continuously around the outer surface of the flexible portion of the end closure (200) (see Figures 1, 4) . Regarding claim 8, Harrelson disclose that an axial end (228 , 232 ) of the flexible portion of the end closure (200) is chamfered to facilitate insertion of the end closure into the canister body (300) (see Figures 1, 4 ; paragraph [0032] ) . Regarding claim 9, Harrelson disclose that the end closure (200) includes a groove (250) that extends around a circumference of an outer perimeter surface (212) of the annular frame portion (216) , the groove configured to seat an O-ring (252) (see Figures 1, 4; paragraph [0031]) . Claims 26-28 are rejected under 35 U.S.C. 102(a)(1)/102(a)(2) as being anticipated by US 201 2 /0 261323 A1 to Badeau et al. (hereinafter “ Badeau ”). Regarding claim 26, Badeau discloses a filter cartridge (filter apparatus 10) comprising: a filter element (filter media 30) located within a canister (housing 12), wherein the canister (12) includes a canister body with an open end and an end closure ( nutplate 14), the end closure (14) having: a central annular element locating feature (connective portion 28); an annular frame portion (outer floating seals 20) circumscribing the element locating feature (28) including an annular rigid attachment portion and an annular flexible portion i.e. flexible fingers projecting from the rigid attachment portion; and radial support ribs projecting between the element locating feature (28) and the rigid attachment portion of the frame portion, wherein the flexible portion is unconstrained by the radial support ribs, the canister body and end closure (14) having cooperating geometry retaining the end closure (14) to the open end of the canister, the cooperating geometry including: an internal annular rib (18) circumscribing an inner surface of the canister, proximate the open end; and an external annular rib (16) circumscribing an outer surface of the flexible portion of the end closure, the external annular rib of the flexible portion of the end closure configured and arranged to engage the internal annular rib of the canister when the end closure is attached to the open end of the canister (see figures 1 - 2, and paragraph s [0066]-[00 70 ] ). Regarding claim 27, Badeau discloses that the internal annular rib (18) extends continuously around the inner surface of the canister (12)(see Figures 1-2) . Regarding claim 28, Badeau discloses that the external annular rib (16) extends continuously around the outer surface of the flexible portion of the end closure (14) (see Figures 1-2) . 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 4 and 6-7 are rejected under 35 U.S.C. 103 as being unpatentable over Harrelson . Harrelson disclose the filter cartridge as described above. Harrelson teaches the internal annular rib (316), the external annular rib (220) and mechanical interference between the external annular rib and the internal annular rib (see Figures 1-4; paragraphs [0025]-[0036]) . Particular height of internal or external annular rib and mechanical interference between the external annular rib and the internal annular rib can be optimized for desired interference fit between the external annular rib and the internal annular rib and would have been obvious to a person of ordinary skill in the art. Claims 4 and 6 differ from Harrelson in reciting that the internal annular rib has an average height of five hundredths of an inch with respect to the inner surface of the canister (claim 4) and the external annular rib has an average height of ten hundredths of an inch with respect to the outer surface of the flexible portion of the end closure (claim 6) . It would have been obvious to one having ordinary skill in the art at the time the invention was made to modify the internal annular rib to have an average height of five hundredths of an inch with respect to the inner surface of the canister and the external annular rib to have an average height of ten hundredths of an inch with respect to the outer surface of the flexible portion of the end closure , since it has been held that discovering an optimum value of a result effective variable involves only routine skill in the art. In re Boesch , 617 F.2d 272, 205 USPQ 215 (CCPA 1980). Claim 7 differs from Harrelson in reciting that the mechanical interference between the external annular rib and the internal annular rib is at least three hundredths of an inch . It would have been obvious to one having ordinary skill in the art at the time the invention was made to modify the mechanical interference between the external annular rib and the internal annular rib to be at least three hundredths of an inch , since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves only routine skill in the art. In re Aller, 105 USPQ 233. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to FILLIN "Enter examiner's name" \* MERGEFORMAT JOHN KIM whose telephone number is FILLIN "Phone number" \* MERGEFORMAT (571)272-1142 . The examiner can normally be reached FILLIN "Work schedule?" \* MERGEFORMAT Maxi Flex . 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, FILLIN "SPE Name?" \* MERGEFORMAT IN SUK BULLOCK can be reached at FILLIN "SPE Phone?" \* MERGEFORMAT 571-272-5954 . 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. /John Kim/ Primary Examiner, Art Unit 1777 JK 3/ 2 5 /26
Read full office action

Prosecution Timeline

Nov 06, 2023
Application Filed
Mar 25, 2026
Non-Final Rejection — §102, §103 (current)

Precedent Cases

Applications granted by this same examiner with similar technology

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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
78%
Grant Probability
90%
With Interview (+11.2%)
2y 11m
Median Time to Grant
Low
PTA Risk
Based on 954 resolved cases by this examiner. Grant probability derived from career allow rate.

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