Prosecution Insights
Last updated: October 25, 2026
Application No. 18/688,337

HOLLOW CYLINDRICAL FILTER, AND MANUFACTURING METHOD

Non-Final OA §103
Filed
Feb 29, 2024
Priority
Sep 10, 2021 — JP 2021-147781 +3 more
Examiner
PREGLER, SHARON
Art Unit
1776
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Fuji Filter Manufacturing Co. Ltd.
OA Round
1 (Non-Final)
78%
Grant Probability
Favorable
1-2
OA Rounds
0m
Est. Remaining
99%
With Interview

Examiner Intelligence

Grants 78% — above average
78%
Career Allowance Rate
704 granted / 902 resolved
+13.0% vs TC avg
Strong +21% interview lift
Without
With
+21.1%
Interview Lift
resolved cases with interview
Typical timeline
2y 7m
Avg Prosecution
43 currently pending
Career history
940
Total Applications
across all art units

Statute-Specific Performance

§101
1.4%
-38.6% vs TC avg
§103
49.6%
+9.6% vs TC avg
§102
18.0%
-22.0% vs TC avg
§112
21.6%
-18.4% vs TC avg
Black line = Tech Center average estimate • Based on career data from 902 resolved cases

Office Action

§103
DETAILED ACTION Election/Restrictions Applicant’s election without traverse of Group I claims 1-4 and 19-20 in the reply filed on 8/6/26 is acknowledged. Claim Rejections - 35 USC § 103 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 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. The factual inquiries for establishing a background for determining obviousness under 35 U.S.C. 103 are summarized as follows: 1. Determining the scope and contents of the prior art. 2. Ascertaining the differences between the prior art and the claims at issue. 3. Resolving the level of ordinary skill in the pertinent art. 4. Considering objective evidence present in the application indicating obviousness or nonobviousness. Claims 1-4 and 19-20 are rejected under 35 U.S.C. 103 as being unpatentable over Hirata et al. US Patent 7,449,042 in view of Fujisawa US Patent 5,849,054. Regarding claim 1 and 2, Hirata teaches a hollow cylindrical filter produced by a method comprising: a) A first winding process by winding metal wire 16 on cylindrical bobbin 19 to form a hollow cylindrical body 15a. The start of wire 16 is fixed at one winding end portion L1 of bobbin 19, thereby securing the start end between inner and outer wound portions. Bobbin 19 is rotated to create the cylindrical body including a first wire rod layer located on an innermost circumference, (column 4 lines 50-55); b) A second winding process of rotating the bobbin 19 and winding the metallic wire rod on an outer circumferential side of the start end portion and the inner cylindrical body to produce an outer cylindrical body (column 5 lines 1-35). Hirata does not explicitly teach a folding process of folding the start end portion of the metallic wire rod is folded and placed between wire rod layers adjacent to each other. However, Fujisawa teaches folding an end potion of a metallic wire cylindrical filter back toward the opposite axial direction and positioning the end within the wound filter structure to prevent the wire from protruding or catching (column 4 lines 10-25). Thus, it would have been obvious to one having ordinary skill in the art to fold Hirata’s start end toward the opposite axial end before winding additional wire over the start end, in order to prevent fraying and protrusions. The combined method would include forming an inner cylindrical body, folding the starting end onto the outer circumferential side of the inner cylindrical body, and then winding additional wire over the start end and inner cylindrical body to form the outer cylindrical body as claimed. Regarding claim 3, Hirata does not explicitly teach the selecting the pitch and number of rod layers to prevent the start end from protruding to the inner diameter side. However, Hirata teaches that pitch and the amount of wire winding are adjustable winding parameters (column 4 lines 43-48). It would have been obvious to one having ordinary skill in the art to select the pitch and number of inner wire layers to provide sufficient underlying wire coverage to maintain the folded start end outward of the innermost layer and prevent inward protrusion. Regarding claims 4, 19 and 20, Hirata does not explicitly teach positioning the folded-back portion inward of the axial end edge of the filter. Fujisawa teaches folding metallic-wire filter end portions and positioning the cut ends inside the filter structure so that they are not exposed or caught on surrounding objects (column 4 lines 10-20). Thus, it would have been obvious to position the folded-back portion of Hirata inward of the axial end edge, as suggested by Fujisawa, to prevent the folded wire portion from protruding or catching during handling. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHARON PREGLER whose telephone number is (571)270-5051. The examiner can normally be reached Monday - Friday 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, In Suk Bullock can be reached at (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. /SHARON PREGLER/Primary Examiner, Art Unit 1772
Read full office action

Prosecution Timeline

Feb 29, 2024
Application Filed
Aug 25, 2026
Non-Final Rejection mailed — §103 (current)

Precedent Cases

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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
99%
With Interview (+21.1%)
2y 7m (~0m remaining)
Median Time to Grant
Low
PTA Risk
Based on 902 resolved cases by this examiner. Grant probability derived from career allowance rate.

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