Prosecution Insights
Last updated: April 19, 2026
Application No. 16/400,600

POLYMER MICROFILTRATION DEVICES, METHODS OF MANUFACTURING THE SAME AND THE USES OF THE MICROFILTRATION DEVICES

Final Rejection §103§112
Filed
May 01, 2019
Examiner
MENON, KRISHNAN S
Art Unit
1777
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Creatv Microtech Inc.
OA Round
7 (Final)
60%
Grant Probability
Moderate
8-9
OA Rounds
3y 2m
To Grant
71%
With Interview

Examiner Intelligence

Grants 60% of resolved cases
60%
Career Allow Rate
879 granted / 1475 resolved
-5.4% vs TC avg
Moderate +12% lift
Without
With
+11.7%
Interview Lift
resolved cases with interview
Typical timeline
3y 2m
Avg Prosecution
72 currently pending
Career history
1547
Total Applications
across all art units

Statute-Specific Performance

§101
1.7%
-38.3% vs TC avg
§103
31.5%
-8.5% vs TC avg
§102
29.4%
-10.6% vs TC avg
§112
26.4%
-13.6% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1475 resolved cases

Office Action

§103 §112
Notice of Pre-AIA or AIA Status The present application is being examined under the pre-AIA first to invent provisions. DETAILED ACTION Election/Restrictions Claims 9-32 is identified as (Withdrawn), but no text appears in the withdrawn claims. Therefore, they are presumed as cancelled. Appropriate claim status indication is required. Claim Rejections - 35 USC § 112 The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112: The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention. Claims 7 and 34 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the written description requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to reasonably convey to one skilled in the relevant art that the inventor or a joint inventor, or for applications subject to pre-AIA 35 U.S.C. 112, the inventor(s), at the time the application was filed, had possession of the claimed invention. Claim 7 recites, “said filter structure retains said flexibility,” which appears to be new matter because there is no support for this limitation in the original disclosure. 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. Claims 7 and 34 are 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. The element “said filter structure retains said flexibility” is unclear. The filter structure as defined herein is a single porous (i.e., having a plurality of apertures) polymer layer. It has a flexibility. Does the claim element, “said filter structure retains said flexibility,” mean when this filter is layered between the inlet layer and the outlet layer, it still retains the same flexibility, even though it is constrained by the inlet and outlet layers? Or, does it mean the filter structure, (that is, the single layer) retains its flexibility as a single layer – an indication that it is not physically or chemically changed when disposed in the device. For further examination, flexibility is considered as a material property of the filter structure, i.e., the single layer polymer with plurality of apertures. Claim Rejections - 35 USC § 103 The following is a quotation of pre-AIA 35 U.S.C. 103(a) which forms the basis for all obviousness rejections set forth in this Office action: (a) A patent may not be obtained though the invention is not identically disclosed or described as set forth in section 102 of this title, if the differences between the subject matter sought to be patented and the prior art are such that the subject matter as a whole would have been obvious at the time the invention was made to a person having ordinary skill in the art to which said subject matter pertains. Patentability shall not be negatived by the manner in which the invention was made. Claims 1-3,5-7 and 33-34 are rejected under pre-AIA 35 U.S.C. 102(b) as being anticipated by, or in the alternative, under 35 USC 103(a) as being unpatentable over Hongo et al (US 2010/0122957), with further evidence from O’Connor et al (US 2002/0187074), with further evidence from applicant’s own admission of prior knowledge. Independent claim 1 and 7: Hongo teaches (see abstract, figures) a filtration device substantially as claimed. Particularly, as seen in fig. 10, it has an inlet 14, inlet volume 54c, a porous membrane 56c, an outlet volume 58c and outlet 16. It also has the top and base layers as claimed. First and second top openings (14,18). Second inlet layer opening is also provided. See figs. 8, 14, 15 etc. The layer materials can be transparent [0137]. PNG media_image1.png 314 521 media_image1.png Greyscale The materials include epoxy for the layers [0040], including the filter. The “photo-definable” term and use of UV appears to be only a part of the method of making, and is not a structural limitation. However, Paragraph [0138] teaches about photo-definable techniques in the microfabrication. Paragraph [0139] teaches the epoxy as EPON SU-8, which is the same negative photo-definable material as applicant has (specification at [0092]). Figures 1-5 show defined shapes for the pores of the filter membrane. Paragraph [0139] also teaches that all layers including filter layer 56(a-e) are made of the same material SU8, which anticipates the “a filter structure consisting of a single polymer layer formed from of an epoxy-based negative photodefinable dry film”. Note that the filters 56 (a-e) in fig. 8 are in single layer (as opposed to a stack.) The films can be coated – [0161] as in claim 5. Analyte recognition elements (claim 6) are inherent- the references teaches separation at the least by particle size, therefore capable of recognizing particle size (broadest reasonable interpretation). Paragraphs [0037] - [0048] teach that the filtration diaphragm (single layer) is a thin film (1-50 microns), thus, it is by nature flexible to roll and unroll, and would retain its flexibility when used in the filter – inherent material property. Paragraphs [0172] – [0176] teach the total thickness of the stack in figs. 12-15 as 0.5 mm, which would also be flexible. The materials listed are metal or polymers, which are inherently flexible, at the least when thin – see [0040]. Applicant’s argument in this regard about Hongo having support for mechanical strength [0048] does not mean that it is made rigid and inflexible. Claims 2, 3, 8: structures recited are clearly visible in the figures. Regarding applicant’s argument that film’s thickness does not inherently result in its flexibility, the rejection is based on thinness that makes it flexible. Moreover, there is no evidentiary showing that Hongo’s thin films are not flexible enough to roll or unroll. Regarding the filter being retaining the unfiltered portion (claim 33), known in the industry as dead-end filter, or discharging the unfiltered portion (claim 34), known as cross-flow filter, both these kinds are well known, and having one for or the other is not inventive, but depend upon the desired application. Regarding the inlet and outlet from the same surface, Hongo has the inlet and outlet at opposite surfaces. However, having the inlet and the outlet from the same surface is just an obvious engineering design detail and does not appear to be critical to the invention. Such designs are also well-known in the art such as taught by O'Connor - see rejection 2 below. Further clarification: The flexibility requirement is only for the filter film, not the entire filter, and only appears to assist in the manufacture. Spec. @[00108]. It is also noted that the claims of the parent, 13/854003, were also similarly rejected, which on appeal was affirmed. The instant claims differ in “flexibility” and “consisting of” language for the filter structure. The definition of “film” itself is very clear in this aspect: it is thin and flexible, according to Merriam Webster. Applicant’s admission and incorporation by reference of the prior arts on photo-definable epoxy materials and filters in [0079] of the specification is further evidence of unpatentability. Arguments are not persuasive, and had been addressed before as well as in the reaction. Claims 1-3,5-7 and 33-34 are rejected under pre-AIA 35 U.S.C. 102(b) as being anticipated by, or in the alternative, under 35 USC 103(a) as being unpatentable over, O’Connor et al (US 2002/0187074), with further evidence from Hongo (as applied in rejection 1 above) and applicant’s admission of prior knowledge. O’Connor teaches a microfluidic multilayer filtration device as shown in the figured copied herein. Details in [0085]. The filter structure described is as in claim 1. Filter 55 is a single layer; and is described as any suitable commercially available material [0081], including epoxy. PNG media_image2.png 669 577 media_image2.png Greyscale O’Connor teaches that the stencil type layered filter is made of, inter alia, photolithographic process [0070], which would make the filter device of photo-definable material, and therefore, would have been obvious, if not anticipated. This type of filters are inherently flexible and thus can be rolled/unrolled. The inlet and the outlet are from the same surface (bottom) - see the figures. The filter also works as a dead-end filter as contemplated in the claims, or having an outlet for the unfiltered fluid would have been obvious to one of ordinary skill as such constructions are well-known (see Hongo and applicant’s own admission detailed in rejection 1 above). The filter material (55) separates the inlet and the outlet volumes, which are clearly visible in the figures. Epoxies – [0060], [0080] and several other places, but it is unclear if the filter itself is made of epoxy. The filter is taught as commercially available, and can be made of a variety of materials [0081] including Mylar®, nylon, etc., which are transparent [0044]. [0082] teaches that the entire device can be made from the filter material. Making the filter from photo-lithography, thus, would have been obvious as further evidenced by Hongo and applicant’s own admission of prior art. Coating or coated elements – see [0084-0085]. Analyte recognition by the filter would have been inherent – similar filter like particle size separation, etc. [0081]. Multiple inlet layer openings – see figs. 13-15. These teachings also confirm that the material for filter is a single polymer. Regarding the negative photo-definable material, the material is UV cured epoxy – which is negative photo-definable as per applicant’s definition (see specification [0083]). Uniformity: [0062]. Other features in claims not discussed herein are already addressed in rejection 1 and is the same in this rejection as well. It is also noted that the claims of the parent, 13/854003, were also similarly rejected, which was affirmed on appeal. The instant claims differ only in “flexibility allowing disposing on a roll or unrolling,” which is shown as inherent in thin films, and the “consisting of” language for the filter structure in claims 1 and 7. Nonetheless, O’Connor teaches the material as flexible in [0076], [0085], [0091], [0092] and other places. A word search in O’Connor for “flexible membrane” gives 4 hits. In [0091]: “the third layer is a flexible membrane defining two vias 208 in fluid communication with the channel 205.” The term “flexibility” appears about 15 times, including “stencil layers may be either rigid or flexible” [0041], and stencil layers and substrate layers can be flexible” in [0045]. Also as shown in rejection 1, the flexibility required is only for the photo-definable dry film which forms the filter, not the entire filter claimed. The flexibility is required only for rolling and unrolling of the film, which is part of the manufacturing process, and not in the filtration device. See spec at [0077], [00105] and [00118]. Response to argument’s: Addressed in the rejection, and above in rejection 1. Response to Arguments Applicant's arguments filed 10/30/25 have been fully considered but they are not persuasive. Arguments are directed to the filter structure being flexible and it retaining its flexibility. They are addressed in the rejection. The filter structure being flexible to roll and unroll is not a patentable limitation. Conclusion THIS ACTION IS MADE FINAL. Applicant is reminded of the extension of time policy as set forth in 37 CFR 1.136(a). A shortened statutory period for reply to this final action is set to expire THREE MONTHS from the mailing date of this action. In the event a first reply is filed within TWO MONTHS of the mailing date of this final action and the advisory action is not mailed until after the end of the THREE-MONTH shortened statutory period, then the shortened statutory period will expire on the date the advisory action is mailed, and any nonprovisional extension fee (37 CFR 1.17(a)) pursuant to 37 CFR 1.136(a) will be calculated from the mailing date of the advisory action. In no event, however, will the statutory period for reply expire later than SIX MONTHS from the mailing date of this final action. Any inquiry concerning this communication or earlier communications from the examiner should be directed to KRISHNAN S MENON whose telephone number is (571)272-1143. The examiner can normally be reached on Flexible, but generally Monday-Friday: 8:00AM-4:30PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Prem Singh can be reached on 5712726381. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. Information regarding the status of an application may be obtained from the Patent Application Information Retrieval (PAIR) system. Status information for published applications may be obtained from either Private PAIR or Public PAIR. Status information for unpublished applications is available through Private PAIR only. For more information about the PAIR system, see http://pair-direct.uspto.gov. Should you have questions on access to the Private PAIR system, contact the Electronic Business Center (EBC) at 866-217-9197 (toll-free). If you would like assistance from a USPTO Customer Service Representative or access to the automated information system, call 800-786-9199 (IN USA OR CANADA) or 571-272-1000. /Krishnan S Menon/ Primary Examiner, Art Unit 1777
Read full office action

Prosecution Timeline

May 01, 2019
Application Filed
Oct 15, 2020
Non-Final Rejection — §103, §112
Apr 19, 2021
Examiner Interview Summary
Apr 19, 2021
Applicant Interview (Telephonic)
Apr 20, 2021
Response Filed
Apr 29, 2021
Final Rejection — §103, §112
Nov 04, 2021
Response after Non-Final Action
Nov 04, 2021
Notice of Allowance
Nov 16, 2021
Response after Non-Final Action
Jun 06, 2022
Request for Continued Examination
Jun 09, 2022
Response after Non-Final Action
Jul 19, 2022
Non-Final Rejection — §103, §112
Jan 26, 2023
Response Filed
Feb 13, 2023
Final Rejection — §103, §112
Aug 17, 2023
Request for Continued Examination
Aug 18, 2023
Response after Non-Final Action
Sep 21, 2023
Final Rejection — §103, §112
Mar 27, 2024
Notice of Allowance
Dec 02, 2024
Response after Non-Final Action
Mar 31, 2025
Request for Continued Examination
Apr 24, 2025
Response after Non-Final Action
Apr 25, 2025
Non-Final Rejection — §103, §112
Oct 30, 2025
Response Filed
Nov 19, 2025
Final Rejection — §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

8-9
Expected OA Rounds
60%
Grant Probability
71%
With Interview (+11.7%)
3y 2m
Median Time to Grant
High
PTA Risk
Based on 1475 resolved cases by this examiner. Grant probability derived from career allow rate.

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