DETAILED ACTION
Applicant’s response November 10, 2025 is acknowledged. Claims 1 and 9-10 are amended and claim 7 is cancelled. Claims 1-6, 8-14, 16-19, and 21 are pending and further considered on the merits.
Response to Amendment
In light of applicant’s amendment, the examiner maintains the grounds of rejection set forth in the office action filed May 9, 2025.
Claim Rejections - 35 USC § 103
The text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action.
Claim(s) 1-6, 8-14, 16-19, and 21 is/are rejected under 35 U.S.C. 103 as being unpatentable over Bagshawe, US 3825410 (Bagshawe, of record) in view of Saitoh et al., US 2005/0041774 (Saitoh).
Regarding claim 1, Bagshawe discloses a dynamic filtration apparatus for removing impurities from a biological product in a heterogeneous mixture (abstract, figs. 1-8) comprising:
A continuous filter membrane (see “tape of filter material…disposed along the length of the carrier band”, C7/L63-68) rolled about a feed reel (REF 32) containing fresh rolled filter membrane and a collection reel (REF 35) configured to collect used filter membrane, the filter membrane having a target region (see “filter locations”, C8/L1-2) configured to continuously move along a length of the filter membrane (via REF 32, 35) and to receive a heterogeneous mixture from at least one output head (REF 51, 52, 53, fig. 6) configured to dispense the heterogeneous mixture onto the target region (C6/L28-32), the filter membrane configured for continuous filtration (via filtration fibers, C4/L60-61, C7/L62-65);
A support system arrangement consisting of:
A static membrane support structure (REF 48, fig. 6, C6/L21-22) to structurally support the target region of the filter membrane positioned between the feed reel and the collection reel, the membrane support structure having a substantially smooth surface (REF 48, fig. 6); and
A vacuum system (REF 43, 49, fig. 6, C6/L21-27) for applying negative pressure across the target region of the filter membrane.
Bagshawe does not disclose the filter membrane being formed of a polymeric material. However, Bagshawe recognizes that the filter material can be selected from a variety of suitable filter materials for the intended purpose of filtration (C4/L56-61). Furthermore, Saitoh discloses a continuous filtration apparatus (abstract, figs. 1-2) comprising a filtration membrane formed from a polymeric material (REF 5, ¶ 0047) extending between a feed reel (REF 6a) and a collection reel (REF 6b).
At the time of invention, it would have been obvious to one having ordinary skill in the art to modify the filter membrane of Bagshawe to utilize the polymeric material as described in Saitoh since it has been shown that such materials are effective for filtration along a continuous filtration system between a feed reel and collection reel. Furthermore, it would have been obvious to one having ordinary skill in the art to modify the filter membrane of Bagshawe to utilize the polymeric material as described in Saitoh since it has been held to be within the general skill of a worker in the art to select known materials on the basis of their suitability for the intended purpose as a matter of obvious design choice absent a showing of criticality or unexpected results (MPEP 2144.07).
Lastly, while Bagshawe discloses embodiments comprising pairs of support members (REF 82, fig. 9) laterally offset from a support structure, Bagshawe does not disclose a filtration apparatus comprising said pairs of support members in the embodiment relied upon above. However, Saitoh discloses a continuous filtration apparatus (abstract, fig. 1) with a moving belt of filter material (REF 5) extending between a feed reel (REF 6a) and a collection reel (REF 6b), and at least a pair of support members (REF 6c, 6d) laterally offset from a support structure (REF 8) to stabilize transport of the moving belt across the support structure (fig. 1).
At the time of invention, it would have been obvious to one having ordinary skill in the art to modify the apparatus of Bagshawe to include the support members as described in Saitoh in order to maintain appropriate tension of the moving belt and provide stability of said moving belt as it extends along separation and analysis components of the system (Saitoh, ¶ 0050).
Regarding claim 2, Bagshawe (in view of Saitoh) discloses an apparatus further comprising a wash line (REF 55, C6/L33-40).
Regarding claims 3 and 17, Saitoh further discloses the filter membrane comprising one of nylon or PTFE (¶ 0047).
Regarding claim 4, Bagshawe (in view of Saitoh) does not disclose the filter membrane having the recited pore size range. However, Bagshawe discloses that the filter membrane is selected according to pore size and other characteristics such that it will retain bound ligand and pass free ligand (C4/L56-59).
Therefore, at the time of invention, it would have been obvious to one having ordinary skill in the art to modify the filter of Bagshawe to have the recited pore size range since it has been held that where the general conditions of a claim are disclosed in the prior art, i.e. suitable pore size ranges determined by retained material particle size (as seen above), discovering the optimum or workable ranges involves only routine skill in the art absent a showing of criticality or unexpected results (MPEP 2144.05, Section II, Part A).
Regarding claim 5, Bagshawe (in view of Saitoh) discloses the static membrane support structure (REF 48) includes a series of parallel slots (fig. 6).
Regarding claim 6, Bagshawe (in view of Saitoh) does not disclose the vacuum system configured to apply negative pressures within the range recited in claim 6. However, Bagshawe discloses using vacuum pressures suitable for separation through the filter membrane.
Therefore, at the time of invention, it would have been obvious to one having ordinary skill in the art to modify the apparatus of Bagshawe (in view of Saitoh) to provide the recited vacuum pressures since it has been held that where the general conditions of a claim are disclosed in the prior art, i.e. suitable vacuum pressures for separation through the filter membrane (as seen above), discovering the optimum or workable ranges involves only routine skill in the art absent a showing of criticality or unexpected results (MPEP 2144.05, Section II, Part A).
Regarding claim 8, Saitoh further discloses that the support member has a substantially smooth contact surface (fig. 1, ¶ 0050).
Regarding claims 9-10, Bagshawe (in view of Saitoh) does not explicitly disclose an apparatus wherein the contact surfaces have the recited static coefficient of friction. However, it is generally known that lower values of static friction correspond to surfaces which minimize friction and increase ease of movement across said surfaces.
Therefore, it would have been obvious to one having ordinary skill in the art at the time the invention was made to modify Bagshawe (in view of Saitoh) to have the recited contact surface static friction coefficient ranges, since it has been held that discovering an optimum range or value of a result effective variable, i.e. coefficient of friction as it relates to ease of movement across a surface, involves only routine skill in the art absent a showing of criticality or unexpected results (MPEP 2144.05, Section II, Part B).
Regarding claim 11, Bagshawe (in view of Saitoh) discloses that the vacuum system (REF 43, 49, fig. 6) comprises at least one vacuum line (REF 33, 45, fig. 6) in communication with the membrane support structure.
Regarding claim 12, Bagshawe (in view of Saitoh) discloses an apparatus further comprising a system configured to control the transport velocity of the filter membrane (see “timing equipment”, C8/L21-31).
Regarding claim 13, Saitoh further discloses an apparatus wherein the feeding reel is powered by a motor (¶ 0058).
Regarding claim 14, Bagshawe (in view of Saitoh) discloses an apparatus wherein the drive mechanism (as rejected in claim 13 above) is controlled by a closed-loop controller that operates a feedback mechanism (see “magnetic or photoptic device”, C6/L61-66).
Regarding claim 16, while Bagshawe (in view of Saitoh) discloses the filter membrane comprising a variety of polymeric substances including nylon, PTFE, polyethylene, polyester, or polyamide (¶ 0047), Bagshawe (in view of Saitoh) does not disclose the filter membrane comprising polyethersulfone. However, it would have been obvious to one having ordinary skill in the art to utilize polyethersulfone due to its similarity to those polymeric substances known in the art and since it has been held to be within the general skill of a worker in the art to select a known material on the basis of its suitability for the intended use as a matter of obvious design choice absent a showing of criticality or unexpected results (MPEP 2144.07).
Regarding claims 18-19, Bagshawe (in view of Saitoh) discloses an apparatus further comprising a vacuum collection vessel (REF 42, 45) configured to collect filtrate, said vacuum collection vessel positioned between the feed reel (REF 32) and the collection reel (REF 35).
Regarding claim 21, Bagshawe (in view of Saitoh) discloses an apparatus capable of purifying a protein (C1/L4-10). Additionally, materials worked upon by the apparatus are not given patentable weight since they are not recited as part of the apparatus (MPEP 2115).
Response to Arguments
Applicant's arguments filed November 10, 2025 have been fully considered but they are not found persuasive.
In response to applicant's argument regarding “a continuous filter membrane”, the examiner directs applicant’s attention to the rejections set forth above and in previous office actions. Bagshawe discloses “where external filtration is employed manufacture of this device may be simplified by use of a tape of filter material such as glass fibre which is disposed along the length of the carrier band and held to the carrier band by adhesive” (C7/L64-68). The examiner interprets “filter material…disposed along the length of the carrier band” as a continuous filter membrane. The remaining arguments with respect to the carrier band are not considered since the examiner is not referencing the carrier band as the continuous filter membrane.
Applicant argues one having ordinary skill in the art would not have modified the carrier band of Bagshawe with the filter membrane disclosed in Saitoh since the carrier band in Bagshawe requires a multitude of additional structural features to perform its intended purpose. In response, the examiner notes the rejection of this limitation does not propose the entire substitution of the carrier band with the filter membrane of Saitoh. Rather, the rejection set forth above recites the interchangeability of the filter material itself, since the prior art recognizes a plurality of equivalent materials (including polymeric materials) for their suitability in the filtration art.
Applicant argues Saitoh does not disclose support members configured to “stabilize the transport of the filter membrane across the membrane support structure”. In response, the examiner directs applicant’s attention to the rejection of claim 1 set forth above. Bagshawe is relied upon to disclose the membrane support structure and support members in an alternative embodiment (fig. 9). Saitoh is relied upon to disclose that the use of support members similar to those in figure 9 of Bagshawe is common in the prior art for maintaining tension and stability of materials being rolled between a feed reel and collection reel. Saitoh teaches that such support members are common in a variety of continuous filtration embodiments and that their incorporation would be within the level of one having ordinary skill in the art.
Applicant’s argument regarding the membrane support structure having a substantially smooth contact surface is not found persuasive. Applicant’s membrane support structure requires parallel slots in order to allow the application of vacuum to facilitate filtration (fig. 8 of applicant’s published application). Since these slots interrupt a substantially smooth contact surface, the examiner interprets the membrane support structure to only require a region of substantially smooth contact surface rather than along an entire surface. The claim language also supports this interpretation. Therefore, the examiner interprets the membrane support structure of Bagshawe (REF 48) to also include regions of smooth contact surfaces (i.e. non-porous regions).
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 DIRK R BASS whose telephone number is (571)270-7370. The examiner can normally be reached 8-4:30 EST Monday-Friday.
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If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Bobby Ramdhanie can be reached on (571) 270-3240. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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DIRK R. BASS
Primary Examiner
Art Unit 1779
/DIRK R BASS/Primary Examiner, Art Unit 1779