Prosecution Insights
Last updated: July 17, 2026
Application No. 18/392,123

SYSTEM AND METHOD FOR REMOVAL OF FLUID FROM A BIOLOGICAL FLUID FILTER

Non-Final OA §103§112
Filed
Dec 21, 2023
Priority
Jan 04, 2023 — provisional 63/478,392
Examiner
ROTONDI, CONNOR JON
Art Unit
1779
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Fenwal Inc.
OA Round
1 (Non-Final)
Grant Probability
Favorable
1-2
OA Rounds

Examiner Intelligence

Grants only 0% of cases
0%
Career Allowance Rate
0 granted / 0 resolved
-65.0% vs TC avg
Minimal +0% lift
Without
With
+0.0%
Interview Lift
resolved cases with interview
Typical timeline
Avg Prosecution
24 currently pending
Career history
20
Total Applications
across all art units

Statute-Specific Performance

§103
97.7%
+57.7% vs TC avg
§112
2.3%
-37.7% vs TC avg
Black line = Tech Center average estimate • Based on career data from 0 resolved cases

Office Action

§103 §112
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 . Information Disclosure Statement The information disclosure statement(s) (IDS) submitted on 17/12/2024 has/have been considered by the examiner. Claim Objections Claims 1, 4, 8, 13, 15, 17, 19, 21, and 23 objected to because of the following informalities: Inconsistent terminology within the claim language. The preambles of claims 1, 17, and 21 all indicate “a fluid filter having an inlet and an outlet”, but in the body of the aforementioned claims, the recited language of “the fluid filter inlet” or “the fluid filter outlet”. Appropriate correction is required. 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. Claims 1, 17, 21 and their dependencies 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 preamble of the claim mentions the filter is used for recovering biological fluid, yet nowhere in the body of the claims is the biological fluid recovered. The claims only mention this fluid being expelled through the outlet of the system, not the recovery of that fluid after is has exited the outlet of the system. Claims 2-16, 18-20, and 22-23 are rejected due to their dependency of the rejected claims mentioned. 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. 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. Claim(s) 1-11, 13, and 15-23 is/are rejected under 35 U.S.C. 103 as being unpatentable over Unger (EP0535143B1), in view of Sasayama (US6129853A). *Note all teachings and mappings from Unger are based on the attached, English, machine-translated version. In regards to claim 1, Unger teaches a system to recover residual biological fluid; {Abstract, "device … for transmitting at least one of three stratified components … to a respective side container"} a reusable hardware unit comprising a fluid filter compression assembly; {References (12-13) "cassette halves"} the fluid filter compression assembly further comprising: a housing comprising an outer wall that defines a housing space that receives the fluid filter; {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container"} at least one bladder positioned within the housing space; {Reference (17) "expandable displacement body"} at least one conduit; {References (4-5, 40) "hoses"} at least one pump; {Top page 9, "The source of fluid 39 may be an air compressor"} wherein the at least one conduit is in fluid communication with the at least one bladder and the at least one pump; {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} and a clamp configured to selectively stop flow through the fluid filter inlet. {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} In regards to claim 2, Unger teaches the system of claim 1, wherein the at least one pump is configured to pump fluid media into the at least one bladder. {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} In regards to claim 3, Unger teaches the system of claim 1, wherein when the fluid filter is disposed in the housing space and the at least one pump pumps fluid media into the at least one bladder, the fluid filter is compressed. {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container" and Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated} In regards to claim 4, Unger teaches the system of claim 3, wherein when the fluid filter contains residual biological fluid from fluid processing, {References (34-36) "plasma, cell concentrate, and buffycoat" respectively} the clamp is used to selectively stop flow through the fluid filter inlet and the at least one pump pumps fluid media into the at least one bladder, {Reference (10) "openable closure device" and Bottom page 8, "A fluid source, for instance an air source, is connected to connector 18 of the displacement body 17, by means of a hose 40" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} at least a portion of the residual biological fluid is expelled through the fluid filter outlet when the fluid filter is compressed. Figure 5, wherein the displacement body (17) has been inflated, and residual components 34 and 35 have left the blood container into containers 37 and 38 respectively} In regards to claim 5, Unger teaches the system of claim 2, wherein the fluid media is air and the at least one pump is an air pump configured to inflate the at least one bladder. {Bottom page 8, A fluid source, for instance an air source, is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated} In regards to claim 6, Unger teaches the system of claim 5, wherein when the fluid filter is disposed in the housing space and the at least one pump pumps air into the at least one bladder, the fluid filter is compressed. {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container" and Figure 5 wherein the displacement body (17) has been inflated, thus compressing the blood bag (1)} In regards to claim 7, Unger teaches the system of claim 1, wherein the outer wall of the filter housing further comprises opposed front and rear walls and opposed side walls connected to the front and rear walls, respectively. {Figure 2 references (12-13) "cassette halves"} In regards to claim 8, Unger teaches the system of claim 1, wherein the outer wall of the filter housing further comprises at least one slot to accommodate the fluid filter inlet or outlet. {Reference (19) "aperture" and Middle page 8, "aperture 19 which accommodates the hoses connecting the blood container to the side containers, and optionally also other hoses"} In regards to claim 9, Unger teaches the system of claim 7, wherein the outer wall of the filter housing further comprises respective slots through the opposed front and rear walls. {Figure 2 references (14-15)} The examiner would like to note for the following listed claims: 10-16 and 19-20 the applicant has claimed multiple of many of the components of the invention such as: conduits, pumps, bladders, etc., while claiming the same function of the individually claimed components from claims 1-9 of the instant application. MPEP 2144.04 states, “mere duplication of parts has no patentable significance unless a new of unexpected result is produced.” Given that with this MPEP teaching along with Unger’s teaching of multiple bladders {Figure 7}, proving that this duplication is already known in the art, the claim mappings referring to individual components will continue to be mapped to the embodiment of Unger, where they are in a singular form. In regards to claim 10, Unger teaches the system of claim 1, wherein: the at least one bladder further comprises first and second bladders being spaced apart and positioned within the housing space; {Reference 17 "expandable displacement body" and references (12-13) "cassette halves"} the at least one conduit further comprises first and second conduits; {References (4-5, 40) "hoses"} at least one pump further comprises first and second pumps; {Top page 9, "The source of fluid 39 may be an air compressor"} and the first conduit is in fluid communication with the first bladder and the first pump, and the second conduit is in fluid communication with the second bladder and the second pump. {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} In regards to claim 11, Unger teaches the system of claim 10, wherein the first and second pumps are configured to pump fluid media into the first and second bladders, respectively. {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} In regards to claim 13, Unger teaches the system of claim 12, wherein when the fluid filter contains residual biological fluid from fluid processing, {References (34-36) "plasma, cell concentrate, and buffycoat" respectively} the clamp is used to selectively stop flow through the fluid filter inlet {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} and the at least the first or second pump pumps fluid media into the respective first or second bladder, {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} at least a portion of the residual biological fluid is expelled through the fluid filter outlet when the fluid filter is compressed. Figure 5, wherein the displacement body (17) has been inflated, and residual components 34 and 35 have left the blood container into containers 37 and 38 respectively} In regards to claim 15, Unger teaches the system of claim 14, wherein when the fluid filter contains residual biological fluid from fluid processing, {References (34-36) "plasma, cell concentrate, and buffycoat" respectively} the clamp is used to selectively stop flow through the fluid filter inlet {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} and the first and second pumps pump fluid media into the respective first and second bladders, {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} at least a portion of the residual biological fluid is expelled through the fluid filter outlet when the fluid filter is compressed. Figure 5, wherein the displacement body (17) has been inflated, and residual components 34 and 35 have left the blood container into containers 37 and 38 respectively} In regards to claim 16, Unger teaches the system of claim 11, wherein the fluid media is air and the first and second pumps are air pumps configured to inflate the respective first and second bladders. {Bottom page 8, A fluid source, for instance an air source, is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated} In regards to claim 17, Unger teaches a method of recovering residual biological fluid; {Abstract, "method… for transmitting at least one of three stratified components … to a respective side container"} engaging the clamp to selectively stop flow through the fluid filter inlet; {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} and engaging the at least one pump to pump fluid media into the at least one bladder, {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} causing the fluid filter to be compressed and to expel residual biological fluid through the fluid filter outlet. {Figure 5 wherein the displacement body (17) has been inflated, thus compressing the blood bag (1)} In regards to claim 18, Unger teaches the method of claim 17, wherein the fluid media is air and the at least one pump is an air pump that when engaged inflates the at least one bladder. {Bottom page 8, A fluid source, for instance an air source, is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated} In regards to claim 19, Unger teaches the method of claim 17, wherein the at least one bladder further comprises first and second bladders being spaced apart and positioned within the housing space, {Reference 17 "expandable displacement body" and references (12-13) "cassette halves"} the at least one conduit further comprises first and second conduits, {References (4-5, 40) "hoses"} at least one pump further comprises first and second pumps, {Top page 9, "The source of fluid 39 may be an air compressor"} and the first conduit is in fluid communication with the first bladder and the first pump, and the second conduit is in fluid communication with the second bladder and the second pump, {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} the method further comprising: engaging the clamp to selectively stop flow through the fluid filter inlet; {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} and engaging the first and second pumps to pump fluid media into the respective first and second bladders, {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} causing the fluid filter to be compressed and to expel residual biological fluid through the fluid filter outlet. {Figure 5 wherein the displacement body (17) has been inflated, thus compressing the blood bag (1)} In regards to claim 20, Unger teaches the method of claim 19, wherein the fluid media is air and the first and second pumps are air pumps that when engaged inflate the respective first and second bladders. {Bottom page 8, A fluid source, for instance an air source, is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated} In regards to claim 21, Unger teaches a system to recover residual fluid; {Abstract, "device … for transmitting at least one of three stratified components … to a respective side container"} a reusable hardware unit comprising a fluid filter compression assembly; {References (12-13) "cassette halves" and reference (17) "expandable displacement body"} the fluid filter compression assembly further comprising: a housing comprising an outer wall that defines a housing space; {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container"} at least one bladder positioned within the housing space; {Reference 17 "expandable displacement body" and references (12-13) "cassette halves"} at least one conduit; at least one pump; {References (4-5, 40) "hoses" and Top page 9, "The source of fluid 39 may be an air compressor"} wherein the at least one conduit is in fluid communication with the at least one bladder and the at least one pump; {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} a clamp configured to selectively stop flow through the fluid filter inlet; {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} and wherein the at least one pump is configured to pump fluid media into the at least one bladder. {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container" and Figure 5 wherein the displacement body (17) has been inflated, thus compressing the blood bag (1)} In regards to claim 22, Unger teaches the system of claim 21, wherein when the fluid filter is disposed in the housing space {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container"} and the at least one pump pumps fluid media into the at least one bladder, the fluid filter is compressed. {Middle page 8, "Cassette haves define an inner space 14 + 15 which corresponds to a filled blood container" and Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated} In regards to claim 23, Unger teaches the system of claim 22, wherein when the fluid filter contains residual biological fluid from fluid processing, Figure 5, wherein the displacement body (17) has been inflated, and residual components 34 and 35 have left the blood container into containers 37 and 38 respectively} the clamp is used to selectively stop flow through the fluid filter inlet {Reference (10) "openable closure device" While this clamping device is only apparent on the outlet of the blood bag in this instance, the device would be capable of being a part of the inlet conduit and would be an obvious modification of the invention to include this device on other conduits of the system} and the at least one pump pumps fluid media into the at least one bladder, {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40"} at least a portion of the residual biological fluid is expelled through the fluid filter outlet when the fluid filter is compressed. Figure 5, wherein the displacement body (17) has been inflated, and residual components 34 and 35 have left the blood container into containers 37 and 38 respectively} Unger does not teach: Claims 1, 17, and 21: A soft sided fluid filter having an inlet and an outlet and which is used by a biological fluid processing system. However, Sasayama teaches all of the limitations of claim(s) 1, 17, and 21 that the Unger does not teach. In regards to claim 1, 17, and 21, Sasayama teaches a soft sided {Column 4 lines 1-12, "material of the bag body 11 … includes a soft polyvinyl material"} fluid filter {Column 2 lines 11-12, "bag body … with a filter material"} having an inlet and an outlet and which is used by a biological fluid processing system. {Column 2 lines 11-12, "bag body having a blood flow inlet and a blood flow outlet"} It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to combine Sasayama with the invention of Unger because these inventions both pertain to the filtration of a biological fluid, in this case blood, with the end goal of the separation of target components within the blood, one through centrifugation, and the other through passing the blood through a material and washing the target species. Although the means of filtration is slightly different the overall goal of each invention, and the components of each device are extremely similar. One of ordinary skill in the art prior to the effective filing date of the claimed invention would be motivated to combine Sasayama to Unger because the structure of the housing of Sasayama allows for the lid to be shut while the device is in operation, thus negating all the risk of damaging the bag body and losing or contaminating the biological fluid. {Sasayama, Column 6 lines 14-19} Claim(s) 12 and 14 is/are rejected under 35 U.S.C. 103 as being unpatentable over Unger (EP0535143B1) and Sasayama (US6129853A), in view of Weasler (US20140066281A1). *Note all teachings and mappings from Unger are based on the attached, English, machine-translated version. The combination of Unger and Sasayama teach all of the limitations of claim(s) 1-11, 13, and 15-23; as mentioned in a prior 103 rejection. In regards to claims 12, Unger further teaches the fluid media is pumped into at least one of the first and second bladders by the respective first or second pump, the fluid filter is compressed. {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated, compressing the blood bag} In regards to claim 14, Unger further teaches the fluid media is pumped into the first and second bladders by the respective first and second pumps, the fluid filter is compressed. {Bottom page 8, "A fluid source … is connected to connector 18 of the displacement body 17, by means of a hose 40" and Figure 5 wherein the displacement body (17) has been inflated, compressing the blood bag} They do not teach: Claims 12 and 14: The system of claim 10, wherein when the fluid filter is disposed in the housing space between the spaced apart first and second bladders. However, Weasler teaches all of the limitations of claim(s) 12 and 14 that the combination of Unger and Sasayama does not teach. In regards to claim 12 and 14, Weasler teaches the system of claim 10, wherein when the fluid filter is disposed in the housing space between the spaced apart first and second bladders. {Figure 6 references (12, 30, 50, and 54) "blood container, holder, first bladder, second bladder" respectively and paragraph 53, "blood packs include additional components such as red cell … filters. Although not shown in the figures, these components can also be included" It would have been obvious to one of ordinary skill in the art prior to the effective filing date of the claimed invention to combine Weasler to the combined invention of Unger and Sasayama because Weasler, similar to the combined invention of Unger and Sasayama, has the function of processing whole blood into various target components such as plasma, red blood cells, etc. through a method of filtration. One of ordinary skill in the art prior to the effective filing date of the claimed invention would be motivated to combine Weasler to Unger and Sasayama because the invention of Weasler has improved processing units to filter whole blood into the various target components. {Weasler, paragraph 73} Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to CONNOR J ROTONDI whose telephone number is (571)272-2058. The examiner can normally be reached M-F 8:00am-4:30pm. 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, Bobby Ramdhanie can be reached at (571) 270-3240. 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. /CONNOR J ROTONDI/Examiner, Art Unit 1779 /Bobby Ramdhanie/Supervisory Patent Examiner, Art Unit 1779
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Prosecution Timeline

Dec 21, 2023
Application Filed
May 04, 2026
Non-Final Rejection mailed — §103, §112 (current)

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1-2
Expected OA Rounds
Grant Probability
Low
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