Prosecution Insights
Last updated: April 18, 2026
Application No. 18/251,394

METHOD FOR FIRE-RESISTANT SEALING OF LINE FEEDTHROUGHS OF THIN PIPES, A SEAL ASSEMBLY PREFABRICATED FOR THIS PURPOSE AND METHOD FOR THE PRODUCTION THEREOF

Non-Final OA §103§112
Filed
May 01, 2023
Examiner
BARRERA, JUAN C
Art Unit
3752
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Hilti Aktiengesellschaft
OA Round
3 (Non-Final)
64%
Grant Probability
Moderate
3-4
OA Rounds
3y 1m
To Grant
98%
With Interview

Examiner Intelligence

Grants 64% of resolved cases
64%
Career Allow Rate
311 granted / 490 resolved
-6.5% vs TC avg
Strong +35% interview lift
Without
With
+35.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 1m
Avg Prosecution
27 currently pending
Career history
517
Total Applications
across all art units

Statute-Specific Performance

§101
0.4%
-39.6% vs TC avg
§103
41.2%
+1.2% vs TC avg
§102
26.2%
-13.8% vs TC avg
§112
27.7%
-12.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 490 resolved cases

Office Action

§103 §112
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 . 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 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. 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 12/04/2025 has been entered. Response to Amendment Amendments to the claims, filed on 12/04/2025, are accepted and do not introduce new matter. Previous 112(a) rejection of claim 19 is overcome by amendment; new matter has been removed from the claim. Previous 112(b) rejections of claims 16, 17 and 19 are overcome by amendment; indefinite language has been fixed in these claims. Claims 1-6 and 8-21 are pending; claim 7 is cancelled. 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. Claim 9 is 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 term “approximately 5 mm” in claim 9 is a relative term which renders the claim indefinite. The term “approximately” is not defined by the claim, the specification does not provide a standard for ascertaining the requisite degree, and one of ordinary skill in the art would not be reasonably apprised of the scope of the invention. As such, it is unclear what the actual measurement in this claim is. 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. Claims 1-6, 8-16 and 19-21 are rejected under 35 U.S.C. 103 as being unpatentable over Monden et al (U.S. 2004/0149390) in view of Munzenberger (U.S. 2016/0178058). Regarding claim 2, Monden teaches a method for producing a prefabricated seal assembly (sealing system 11) for fire-resistant sealing (Pars 0001-0002) of an opening in a wall (opening of wall 1) or ceiling, through which a line (2) is passed (pipeline 2 passes through wall 1), the method comprising: cutting a strip-shaped fire protection bandage (sealing strip 3, which is disclosed as a fire protection strip, see Par 0027) to a length which corresponds to a circumference of the line (Par 0025 discloses cutting the strip 3 to length that corresponds to the diameter of the line 2), with or without an overlap (the overlap is claimed with alternate language “or” as such the prior art does not need to teach it in order to read on claim language), the fire protection bandage comprising fire-retardant and/or intumescent material (the bandage 3 comprises an intumescent material, see Par 0027), the bandage having two edges which are intended to extend in the circumferential direction of the line (after the bandage is cut, it defines two edges, wherein the edges extends in a circumferential direction around the line to meet after being wrapped around the line, as seen in Fig 1a); and optionally, applying a removable transport protection film to at least one surface of the putty strip and/or optionally, rolling up the fire protection bandage provided with the putty strip to form a layer having an overlap (this limitation is optional as such the prior art does not need to teach it in order to read on claim language). However, Monden does not teach the method comprising a step of applying a putty strip along one of two edges of the cut-to-length fire protection bandage, the strip of putty being pressed against or otherwise attached to the one of two edges on an outer surface of the fire protection bandage that is not placed on the line. Munzenberger teaches a method of fire protecting a line (line defined by cylindrical structure seen in Fig 2, which is disclosed as a pipe or cable, see Par 0012) , comprising a step of applying a putty strip (gasket 100 is disclosed as a putty gasket, in shape of a circular strip, see Par 0007), the strip of putty being pressed against or otherwise attached to an outer surface of the line (as disclosed in Pars 0009-0011, the user presses the putty ring 100 against the outer surface of the pipe and the opening in order to fully seal the putty against the pipe and the wall, thus sealing the opening). It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified Monden to incorporate the teachings of Munzenberger to provide a step of applying a putty ring to the fire protection bandage in order to properly seal a gap, i.e. opening, between the pipe and the wall (as disclosed in Par 0003 of Munzenberger), and further, the putty can also aid in fire protection due to its composition (as disclosed in Par 0017 of Munzenberger). In combination, the putty strip of Munzenberger is placed along the bandage of Monden, which includes the two edges of the cut-to-length fire protection bandage, and the strip of putty being pressed against or otherwise attached to the one of two edges on an outer surface of the fire protection bandage that is not placed on the line (the outer surface of the bandage is where the putty strip is pressed on, wherein the outer surface of the bandage, i.e. layer 31, is not in contact with the line, see Fig 1a of Monden). Regarding claim 1, Monden and Munzenberger teach a method according to claim 2, further comprising: placing the produced seal assembly which is prefabricated by the method around the line (as disclosed in Par 0025 and 0027 of Monden, the fire protection bandage 3 is premade, see Fig 2, and then cut to the length of the line; as such, the bandage 3 is prefabricated before being placed around the line, as seen in Fig 1b; as disclosed in Par 0049, 0054, etc. of Munzenberger, the putty strip 100 is prepared with certain chemicals depending on intended use, i.e. the putty strip is prefabricated before being applied; as such, the protection bandage and the putty strip, which make up the seal assembly are prefabricated, thus reading on this limitation), such that a layer of fire protection bandage is formed (as seen in Fig 1a and 1b of Monden, the fire protection bandage forms a protective layer). Regarding claim 3, Monden and Munzenberger teach a method for fire-resistant sealing of a line (2 of Monden) feedthrough using a seal assembly produced from the method according to claim 2, the method for fire-resistant sealing comprising: placing the seal assembly around the line (as seen in Fig 1a of Monden and Fig 2 of Munzenberger), such that a layer of the fire protection bandage is formed on the line (layer 32 of the bandage is placed on the line, see Fig 1a of Monden), optionally with an overlap (the overlap is claimed with alternate language “optionally” as such the prior art does not need to teach it in order to read on claim language), wherein a peripheral edge of the fire protection bandage that is provided with the putty strip protrudes outward from the opening (as seen in Fig 1a of Monden, the bandage includes a peripheral edge that protrudes the bandage’s width from the opening of the wall 1; in combination the peripheral edge would include the putty strip); removing the transport protection film, if necessary; and shaping the putty strip to form a putty ring of a larger outer diameter than the opening diameter, such that the putty ring closes the opening and extends beyond an edge thereof, and pressing the putty ring formed in this way against the fire protection bandage and against the edge in order to seal the line feedthrough (the step of providing a transportation film is an optional step, as claimed in claim 2; as such the prior art does not need to teach this in order to read on claim language). Regarding claim 4, Monden and Munzenberger teach the method according to claim 3. However, they do not teach the method wherein the line has a diameter in a range of between 16 mm and 32 mm. Nonetheless, Monden discloses the method being used to protect pipes, i.e. lines, of different diameters (see Par 0002). As such, It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to select any suitable line diameter, including 16-32 mm, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves routine skill in the art. As it was determined in In re Aller: "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation" (see MPEP 2144.05 II A). In the present case, Moden and Munzenberger disclose all the general structure and steps of the claim. Therefore, it would be obvious to find an optimal or workable line diameter. Furthermore, Applicant has not disclosed any criticality for having the line diameter be 16-32 mm. Finally, it would be obvious to try (see KSR MPEP 2141 III) different line diameters in order to perform the method on different sizes of lines, based on the intended purpose. Regarding claim 5, Monden and Munzenberger teach the method according to claim 2, wherein the putty of the putty strip is elastically and/or plastically deformable; and/or dense; and/or adhesive; and/or formed as a crosslinked rubber-based rubber product; and/or formed having fire protection additives (the putty 100 of Munzenberger has fire protection additives, see Pars 0013). Note: the features disclosed here are claimed with optional “or” language; as such the prior art does not need to teach all of them in order to read on claim language. Regarding claim 6, Monden and Munzenberger teach the method according to claim 2, wherein the fire protection bandage (strip 3 of Monden) has a flexible carrier layer (layer 31 disclosed as a carrier layer, see Par 0027), to which a fire protection wrap (inlay 32) made of an intumescent material is attached (layer 32 is made of an intumescent material, see Par 0027 of Monden). Regarding claim 8, Monden and Munzenberger teach the method according to claim 2. However, they do not explicitly teach the method wherein the fire protection bandage is cut to a reduced width before or after being cut to length (Moden teaches the bandage having a width that matches the length of the support elements 42, as seen in Fig 1b, wherein the length of the support elements varies depending on intended use, see Par 0018; as such, the width of the bandage is selected prior to cutting the length). However, they do not teach the width being of 30 mm. Nonetheless, It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to select any suitable width range, including 30 mm, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves routine skill in the art. As it was determined in In re Aller: "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation" (see MPEP 2144.05 II A). In the present case, Monden and Munzenberger disclose all the general structure and steps of the claim. Considering that Monden identifies selecting the width of the bandage, as stated in Par 0018, it would be obvious to find an optimal or workable bandage width. Furthermore, Applicant has not disclosed any criticality for having the width be 30 mm. Finally, changes in bandage width would affect the characteristics of the sealing assembly, a thicker bandage would offer more protection along the line for example. As such, bandage width is a result-effective variable. Therefore, it would be obvious to try (see KSR MPEP 2141 III) different bandage widths to meet any desired protection characteristic, based on the line used. Regarding claim 9, as best understood, Monden and Munzenberger teach the method according to claim 3, wherein the fire protection bandage protrudes outward from the opening after being placed around the line (as seen in Fig 1a of Monden, the bandage 3 protrudes radially outward from the opening, in order to seal the opening). However, Monden and Munzenberger do not explicitly teach the bandage protruding 5 mm. Nonetheless, it would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to select any suitable protrusion dimension, including 5 mm, since it has been held that where the general conditions of a claim are disclosed in the prior art, discovering the optimum or workable ranges involves routine skill in the art. As it was determined in In re Aller: "[W]here the general conditions of a claim are disclosed in the prior art, it is not inventive to discover the optimum or workable ranges by routine experimentation" (see MPEP 2144.05 II A). In the present case, Monden and Munzenberger disclose all the general structure and steps of the claim. Considering that Monden identifies the bandage dimension as configured to seal the opening, as stated in Par 0025, it would be obvious to find an optimal or workable bandage protrusion. Furthermore, Applicant has not disclosed any criticality for having the protrusion be 5 mm. Finally, changes in bandage protrusion would affect the characteristics of the sealing assembly, a thicker bandage protrusion would offer more protection along the opening for example. As such, bandage protrusion is a result-effective variable. Therefore, it would be obvious to try (see KSR MPEP 2141 III) different bandage widths to meet any desired protection characteristic, based on the line used. Regarding claim 10, Monden and Munzenberger teach a seal assembly (sealing system 11 of Monden) for fire-resistant sealing of an opening in a wall (opening of wall 1 of Monden) or ceiling, through which a line (2) is passed (pipeline 2 passes through wall 1, as seen in Fig 1b of Monden), wherein the seal assembly is produced according to the method of claim 2 (as taught by Monden and Munzenberger in combination, see claim 2 rejection). Regarding claim 11, Monden and Munzenberger teach the seal assembly according to claim 10, wherein the seal assembly is designed as a roll product (as seen in Fig 2 of Monden). Regarding claim 12, Monden and Munzenberger teach the method according to claim 2, wherein the fire protection bandage provided with the putty strip is rolled up to form the simple layer having the overlap, and wherein overlapping ends of the fire protection bandage are temporarily attached to one another by some of the putty strip or by additional putty (the overlap is an optional feature, as claimed in claim 2; as such the prior art does not need to teach this in order to read on claim language). Regarding claim 13, Monden and Munzenberger teach the method according to claim 6, wherein the flexible carrier layer is a woven fabric layer (carrier layer 31 of Monden is disclosed as a fabric; wherein the general definition of a fabric is a material produced by weaving or knitting fibers). Regarding claim 14, Monden and Munzenberger teach the method according to claim 6, wherein fire protection wrap is a continuous fire protection wrap (wrap layer 32 of Monden is layer 32 is made of an intumescent fire proof material, see Par 0027; as seen in Fig 2, this wrap is continuous). Regarding claim 15, Monden and Munzenberger teach the seal assembly according to claim 10, wherein the fire protection bandage provided with the putty strip is rolled up to form the simple layer having the overlap, and wherein overlapping ends of the fire protection bandage are attachable to one another by some of the putty strip or by additional putty (the overlap is an optional feature, as claimed in claim 2; as such the prior art does not need to teach this in order to read on claim language). Regarding claim 16, Monden and Munzenberger teach a method for fire-resistant sealing of a line feedthrough using a seal assembly produced from the method for producing a seal assembly for fire resistant sealing of an opening in a wall or ceiling according to claim 2, comprising applying the removable transport protection film (release paper 150 of Munzenberger; release paper 150 is a transport protection film that is attached to the putty strip 100, as disclosed in Par 0010; thus reading on the limitations regarding the removable transport protection film disclosed in claim 2). Regarding claim 19, Monden and Munzenberger teach the method of claim 2, wherein a removable transport protection film (release paper 150 of Munzenberger) is applied to at least one surface of the putty strip in order to protect the putty strip from mechanical damage or from accidentally adhering to surfaces which are not intended, such that the resulting seal assembly is prefabricated for future use (Par 0010 of Munzenberger discloses pulling off the film 150 when installing the putty; as such the film is intended to prevent the putty from accidentally adhering to surfaces when not intended). Regarding claim 20, Monden and Munzenberger teach the method of claim 2, which results in a prefabricated seal assembly (as disclosed in Par 0025 and 0027 of Monden, the fire protection bandage 3 is premade, see Fig 2, and then cut to the length of the line; as such, the bandage 3 is prefabricated before being placed around the line, as seen in Fig 1b; as disclosed in Par 0049, 0054, etc. of Munzenberger, the putty strip 100 is prepared with certain chemicals depending on intended use, i.e. the putty strip is prefabricated before being applied; as such, the protection bandage and the putty strip, which make up the seal assembly are prefabricated, thus reading on this limitation), (as disclosed in Par 0025 and 0027 of Monden, the fire protection bandage 3 is premade, see Fig 2, and then cut to the length of the line; as such, the bandage 3 is prefabricated before being placed around the line, as seen in Fig 1b; as disclosed in Par 0049, 0054, etc. of Munzenberger, the putty strip 100 is prepared with certain chemicals depending on intended use, i.e. the putty strip is prefabricated before being applied; as such, the protection bandage and the putty strip, which make up the seal assembly are prefabricated, thus reading on this limitation), which can be used for fire-resistant sealing of an opening in a wall or ceiling, through which a line is passed (as seen in Fig 1b and Par 0010 of Monden, the seal assembly is fire-resistant and covers an opening in a wall 1 through which line 2 is passed). Regarding claim 21, Monden and Munzenberger teach the method of claim 2, wherein the putty strip comprises a butyl rubber (as disclosed in Par 0016, 0060 and 0062, the putty strip comprises butyl rubber). PNG media_image1.png 474 626 media_image1.png Greyscale Claims 17 and 18 are rejected under 35 U.S.C. 103 as being unpatentable over Monden et al (U.S. 2004/0149390) in view of Munzenberger (U.S. 2016/0178058); further in view of Collins (U.S. 2006/0027388). Regarding claim 17, Monden and Munzenberger teach a method for fire-resistant sealing of a line feedthrough using a seal assembly produced from the method for producing a seal assembly for fire resistant sealing of an opening in a wall or ceiling according to claim 2. However, they do not teach the method further comprising rolling up the fire protection bandage provided with the putty strip to form a layer having an overlap. Collins teaches a flashing kit for wall penetrations with fire retardant characteristics (see Par 0027) and a method of preparing the seal (see Fig 2) comprising rolling up a fire protection bandage (32) forming a layer having an overlap (as seen in Fig 2 and disclosed in Par 0022). It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified Monden and Munzenberger to incorporate the teachings of Collins to provide the fire protection bandage with an overlap in order to prevent moisture and water from seeping between the leading edge (as disclosed in Par 0022 of Collins), which would further improve the seal by preventing smoke or gasses from passing through the penetration. In combination, the bandage is provided with the putty strip (as taught by Munzenberger) to form the overlap. Regarding claim 18, Monden and Munzenberger teach the method for fire-resistant sealing of a line feedthrough using a seal assembly produced from the method according to claim 16. However, they do not teach the method further comprising rolling up the fire protection bandage provided with the putty strip to form a layer having an overlap. Collins teaches a flashing kit for wall penetrations with fire retardant characteristics (see Par 0027) and a method of preparing the seal (see Fig 2) comprising rolling up a fire protection bandage (32) forming a layer having an overlap (as seen in Fig 2 and disclosed in Par 0022). It would have been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to have modified Monden and Munzenberger to incorporate the teachings of Collins to provide the fire protection bandage with an overlap in order to prevent moisture and water from seeping between the leading edge (as disclosed in Par 0022 of Collins), which would further improve the seal by preventing smoke or gasses from passing through the penetration. In combination, the bandage is provided with the putty strip (as taught by Munzenberger) to form the overlap. Response to Arguments Applicant's arguments filed 12/04/2025 have been fully considered but they are not persuasive. Applicant argued against the rejection of the claim using Monden in view of Munzenberger; stating that neither of them teach a method for producing a prefabricated assembly for sealing. Applicant points to the addition of “prefabricated” in the preamble of the claim in the latest amendments. Examiner respectfully disagrees and notes that adding “prefabricated” to the preamble of the claim carries limited to no patentable weight. In fact, none of the method steps in the body of the claim require any limitations regarding prefabrication. And the seal assembly does not breath meaning or vitality into the body of the claim. In other words, the body of the claim remains broad enough and does not explicitly state that the steps are for making the seal assembly, much less prefabrication of it. Examiner notes that the claims would need to recited positive steps of manufacturing a prefabricated seal in the body of the claim. Merely adding “prefabricated” in the body of the claim is not enough to distinguish the claims from the current grounds of rejection. As such, Examiner maintains this rejection. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to JUAN C BARRERA whose telephone number is (571)272-6284. The examiner can normally be reached on M-F Generally 10am-4pm and 6-8pm. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, ARTHUR O. HALL can be reached on 571-270-1814. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. If there are any inquiries that are not being addressed by first contacting the Examiner or the Supervisor, you may send an email inquiry to TC3700_Workgroup_D_Inquiries@uspto.gov. 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. /JUAN C BARRERA/ Examiner, Art Unit 3752 /ARTHUR O. HALL/Supervisory Patent Examiner, Art Unit 3752
Read full office action

Prosecution Timeline

May 01, 2023
Application Filed
May 23, 2025
Non-Final Rejection — §103, §112
Jun 27, 2025
Response Filed
Nov 04, 2025
Final Rejection — §103, §112
Dec 04, 2025
Response after Non-Final Action
Jan 09, 2026
Request for Continued Examination
Feb 13, 2026
Response after Non-Final Action
Mar 21, 2026
Non-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

3-4
Expected OA Rounds
64%
Grant Probability
98%
With Interview (+35.0%)
3y 1m
Median Time to Grant
High
PTA Risk
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