Prosecution Insights
Last updated: April 19, 2026
Application No. 17/429,223

FILTER SEAL ASSEMBLY AND SYSTEM

Non-Final OA §103
Filed
Aug 06, 2021
Examiner
HOBSON, STEPHEN
Art Unit
1776
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Donaldson Company Inc.
OA Round
5 (Non-Final)
65%
Grant Probability
Favorable
5-6
OA Rounds
3y 2m
To Grant
86%
With Interview

Examiner Intelligence

Grants 65% — above average
65%
Career Allow Rate
398 granted / 611 resolved
At TC average
Strong +21% interview lift
Without
With
+21.2%
Interview Lift
resolved cases with interview
Typical timeline
3y 2m
Avg Prosecution
53 currently pending
Career history
664
Total Applications
across all art units

Statute-Specific Performance

§101
0.3%
-39.7% vs TC avg
§103
45.9%
+5.9% vs TC avg
§102
19.7%
-20.3% vs TC avg
§112
30.5%
-9.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 611 resolved cases

Office Action

§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 . 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 7 Nov. 2025 has been entered. Claims 13-15 and 17-20 are rejected under 35 U.S.C. 103 as being unpatentable over Raether et al. US 2012/0011815 (hereafter Raether) and further in view of Osendorf et al. US 2015/0101299 (hereafter Osendorf) Regarding claim 13, Raether teaches a tubesheet (620 in Fig 46) comprising: a substantially planar sheet of material having a length and a width (as shown in Fig 46) and defining a series of filter openings (621) across the length and width of the sheet of material, wherein each of the filter openings in the series of filter openings extends through the sheet of material in an axial direction and has an oblong profile orthogonal to the axial direction (as shown in Fig 46, ¶187-190). Raether does not teach wherein the sheet of material defines a projection extending into each of the filter openings and a recess extending out from each of the filter openings, wherein the projection and recess are axially aligned, and wherein the projection and recess define an inner perimetric sealing surface. Osendorf (in Fig 104 embodiment) teaches a sheet (sheet comprising filter opening 1870) wherein the sheet of material defines a projection (1872) extending into each of the filter openings and a recess (1873) extending out from each of the filter openings, wherein the projection and recess are axially aligned, and wherein the projection and recess define an inner perimetric sealing surface (1871). Osendorf teaches where the projection and recesses form a radial seal (¶517-524) which is releaseable (¶399) and where the seal is one of two seals (¶368). Further, the seal prevents rotation (¶65). 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 filter openings (621) of Raether by incorporating the projections (1872) and recesses (1873) of Osendorf in order to define a radial seal (¶517-524), be releasable (¶399), and prevent rotation (¶65). Regarding claim 14, Raether in view of Osendorf teaches all the limitations of claim 13. Raether does not teach wherein each of the filter openings defines a plurality of projections (1872) and a plurality of recesses (1873) in axial alignment, wherein the projections alternate with the recesses about a portion of each filter opening (as shown in Figs 104-105). Osendorf (in Fig 104 embodiment) teaches wherein the filter opening defines a plurality of projections and a plurality of recesses in axial alignment, wherein the projections alternate with the recesses about a portion of each filter opening (as shown in Figs 104-105). 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 filter openings (621) of Raether by incorporating the projections (1872) and recesses (1873) of Osendorf in order to define a radial seal (¶517-524), be releasable (¶399), and prevent rotation (¶65). The modification would have resulted in wherein each of the filter openings defines a plurality of projections and a plurality of recesses in axial alignment, wherein the projections alternate with the recesses about a portion of each filter opening. Regarding claim 15, Raether in view of Osendorf teaches all the limitations of claim 14. Raether does not teach wherein the plurality of projections and plurality of recesses form undulations extending along a curve. Osendorf (in Fig 104 embodiment) teaches wherein the plurality of projections and plurality of recesses form undulations extending along a curve (as shown in Figs 104-105) 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 filter openings (621) of Raether by incorporating the projections (1872) and recesses (1873) of Osendorf in order to define a radial seal (¶517-524), be releasable (¶399), and prevent rotation (¶65). Regarding claim 17, Raether in view of Osendorf teaches all the limitations of claim 13. Raether further teaches wherein a profile of each filter opening defines a first elongate side, a second elongate side, a first end and a second end (as shown in Fig 46). Raether does not teach the projection extends out from the filter opening from the first elongate side The combination of claim 13 further teaches the projection extends out from the filter opening from the first elongate side because the recesses and projections of Osendorf would extend around the entirety of the oblong profile of the Raether filter openings. Regarding claim 18, Raether in view of Osendorf teaches all the limitations of claim 17. Raether does not teach wherein the recess extends into each filter opening on the second elongate side. The combination of claim 17 further teaches wherein the recess extends into each filter opening on the second elongate side because the recesses and projections of Osendorf would extend around the entirety of the oblong profile of the Raether filter openings. Regarding claim 19, Raether in view of Osendorf teaches all the limitations of claim 17. Raether (Fig 46) teaches wherein the profile of each filter opening is symmetrical (symmetric about the line between the midpoints of the two long sides; symmetric about the line between the midpoints of the two short sides; symmetric about the plane at the midpoint of the tubesheet’s thickness). Osendorf (Figs 104-105) also teaches wherein the profile of each filter opening is symmetrical (symmetric about multiple lines, each line bisecting the opening and having an endpoint at peak/trough of one projection and/or recess; symmetric about the plane at the midpoint of the opening’s thickness). The combination of claim 17 further teaches wherein the profile of each filter opening is symmetrical because the recesses and projections of Osendorf would extend around the entirety of the oblong profile of the Raether filter openings. Regarding claim 20, Raether in view of Osendorf teaches all the limitations of claim 13. Raether further teaches wherein a first filter opening defined in the tubesheet has a first longitudinal axis and a second filter opening defined in the tubesheet has a second longitudinal axis, and the first longitudinal axis and the second longitudinal axis are 10 degrees to 90 degrees apart (as shown in Fig 46 where the axes are rotated to cover the surface around tubesheet 620). Claim 16 is rejected under 35 U.S.C. 103 as being unpatentable over Raether in view of Osendorf as applied to claim 13 above, and further in view of Clements US 2010/0101195 (hereafter Clements). Regarding claim 16, Raether in view of Osendorf teaches all the limitations of claim 13. Raether does not teach wherein the sheet of material comprises a sheet of metal. Clements teaches a filter comprising a tube sheet (44) made of a suitable material such as sheet metal (¶22). 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 tube sheet (620) by making the tubesheet of metal (¶22) as a matter of obvious selection of a known material based on its suitability for its intended use (MPEP §2144.07) for instance because of metal’s strength and air impermeability. Response to Arguments The following is a response to Arguments filed 7 Nov. 2025: Applicant argues that Raether modified by Baseotto does not teach pending claim 1. The argument is moot because the Baseotto reference is not relied upon in the current rejection. A new rejection is presented above in view of Raether and Osendorf. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to STEPHEN HOBSON whose telephone number is (571)272-9914. The examiner can normally be reached 9am-5pm. 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, Jennifer Dieterle can be reached at 571-270-7872. 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. /STEPHEN HOBSON/Examiner, Art Unit 1776
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Prosecution Timeline

Aug 06, 2021
Application Filed
Feb 02, 2024
Non-Final Rejection — §103
May 08, 2024
Response Filed
May 24, 2024
Final Rejection — §103
Jul 24, 2024
Response after Non-Final Action
Aug 30, 2024
Response after Non-Final Action
Aug 30, 2024
Notice of Allowance
Oct 16, 2024
Response after Non-Final Action
Jan 11, 2025
Non-Final Rejection — §103
Apr 16, 2025
Response Filed
Aug 05, 2025
Final Rejection — §103
Nov 07, 2025
Request for Continued Examination
Nov 12, 2025
Response after Non-Final Action
Mar 26, 2026
Non-Final Rejection — §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

5-6
Expected OA Rounds
65%
Grant Probability
86%
With Interview (+21.2%)
3y 2m
Median Time to Grant
High
PTA Risk
Based on 611 resolved cases by this examiner. Grant probability derived from career allow rate.

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