Prosecution Insights
Last updated: April 19, 2026
Application No. 18/256,889

PROSTHETIC HEART VALVE

Non-Final OA §102§103
Filed
Jun 09, 2023
Examiner
BLASS, PARIS MARIE
Art Unit
3774
Tech Center
3700 — Mechanical Engineering & Manufacturing
Assignee
Shanghai Microport Cardioflow Medtech Co. Ltd.
OA Round
1 (Non-Final)
59%
Grant Probability
Moderate
1-2
OA Rounds
3y 9m
To Grant
99%
With Interview

Examiner Intelligence

Grants 59% of resolved cases
59%
Career Allow Rate
13 granted / 22 resolved
-10.9% vs TC avg
Strong +47% interview lift
Without
With
+47.4%
Interview Lift
resolved cases with interview
Typical timeline
3y 9m
Avg Prosecution
48 currently pending
Career history
70
Total Applications
across all art units

Statute-Specific Performance

§101
0.9%
-39.1% vs TC avg
§103
48.4%
+8.4% vs TC avg
§102
30.8%
-9.2% vs TC avg
§112
15.2%
-24.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 22 resolved cases

Office Action

§102 §103
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 (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. Priority Acknowledgment is made of applicant's claim for foreign priority based on an application filed in China on 12/11/2020. It is noted, however, that applicant has not filed an English translation of the certified copy of the 202011459644.9 application as required by 37 CFR 1.55. Claim Rejections - 35 USC § 102 The following is a quotation of the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. Claim 1 is rejected under 35 U.S.C. 102(a)(1) as being anticipated by US 20180296341 A1 (hereafter --Noe--). Regarding Claim 1, Noe discloses an artificial heart valve prosthesis, comprising: a stent comprising at least two commissures spaced circumferentially around the stent (see annotated valve prosthesis, stent, and commissures in Figure 10 below), wherein each of the commissures is provided with a first window and a second window, which are arranged along an axial direction of the stent (see annotated first and second windows in Figure 18B below), and wherein the first window is located closer to an outflow end of the stent (see annotated outflow end in Figure 18B below); and at least two leaflets arranged circumferentially around the stent (see annotated leaflets in Figure 10 below), wherein each of the leaflets comprises a main segment and flaps arranged on opposite circumferential sides of the main segment (see annotated main segment in Figure 10, see annotated flaps in Figure 18B below), wherein the main segment is disposed on an inner side of the stent (see annotated main segment in Figure 10 below), each of the flaps passed through the second window and at least partially covering an outer surface of the commissure (see annotated flaps, outer surface, and second window in Figure 18B below, see also paragraph [0133]), and wherein the flap is sutured at the first window and the second window (see paragraph [0133]. Noe discloses the flap is sutured into the holes 1819 and therefore the flap is sutured “at” the first window and second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online for “at”). Since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim. PNG media_image1.png 407 701 media_image1.png Greyscale PNG media_image2.png 588 1280 media_image2.png Greyscale 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 text of those sections of Title 35, U.S. Code not included in this action can be found in a prior Office action. 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 2-16 are rejected under 35 U.S.C. 103 as being unpatentable over US 20180296341 A1 (hereafter --Noe--). Regarding Claim 2, Noe discloses the artificial heart valve prosthesis according to claim 1, further comprising hinge sheets (see annotated hinge sheet 1818 in Figures 18A-18E above), wherein the hinge sheet is provided with a through hole (see through hole 1819 in Figures 18A-18E above), and wherein the hinge sheet is sutured at the first window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 and therefore the flap is sutured “at” the first window and second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online synonyms for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim, wherein each of the hinge sheets is at least partially arranged between the commissure and the flap (see annotated flap and hinge sheet in Figures 18A-18E below). The limitation “between” is being interpreted broadly as “acting between,” in which the hinge sheet acts between the flap and the commissure (see paragraph [0133]). This embodiment of Noe disclose further wherein the hinge sheet is provided with a through hole for passage therethrough of the flap. Another embodiment of Noe discloses another variation of a hinge sheet (see annotated hinge sheet 1515 in Figures 15B and 15C). This embodiment of Noe teaches wherein the hinge sheet is provided with a through hole for passage therethrough of the flap (see annotated flaps and through hole in Figures 15B and 15C). PNG media_image3.png 561 419 media_image3.png Greyscale Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention for the hinge sheet 1818 to have the through hole of 1515, thereby having a through hole for passage therethrough of the flap, as by doing so would evenly distribute high stress areas of leaflet along the length of strut (see paragraph [0132]) and since it is disclosed in Noe that combinations of different embodiments would be apparent those of skill in the art upon reviewing the above description (see paragraph [0153]). PNG media_image4.png 588 1280 media_image4.png Greyscale Regarding Claim 3, Noe as modified discloses the artificial heart valve prosthesis according to claim 2, [wherein the hinge sheet covers the first window,] or wherein the flap is sutured to the hinge sheet (see paragraph [0133] denoting that the flap is sutured into holes 1819 of the hinge sheet). Regarding Claim 4, Noe as modified discloses the artificial heart valve prosthesis according to claim 2, wherein the second window is delimited by side support arms arranged circumferentially around the stent (see side arms annotated Figure 18E above), wherein: the hinge sheet at least partially covers an outer surface, an outer side face and an inner surface of the side support arm (see hinge sheet in Figure 18A and 18D covering the entirety of the second window side arms from the view of the outside of the frame), and each of the flaps comprises a head portion, a middle portion and a trailing portion, which are sequentially joined (see annotated head, middle, and trailing portion in Figures 18B and 18D below), wherein the head portion is inserted in the second window and the through hole (see annotated head portion being inserted into second window in Figure 18B below, and see Figure 15B and 15C showing the flaps inserted into the through hole, as the hinge sheet 1818 is modified by this embodiment to include this through hole for passage of the flaps), wherein the middle portion extends over the outer surface (see annotated middle portion and outer surface in Figure 18B below), the outer side face and the inner surface of the side support arm so as to wrap a portion of the hinge sheet arranged on the side support arm (see annotated middle portion in Figure 18B below, outer side face, and inner surface in Figure 18B below) and wherein the trailing portion overlaps a portion of the main segment in the leaflet (see annotated trailing portion in Figure 18B below, the trailing portion defined as the rest of the flap of the leaflet until the main segment in the leaflet, see also paragraph [0133] denoting that 1822a,b are the arms of the leaflets inside of the stent). PNG media_image5.png 588 844 media_image5.png Greyscale Regarding Claim 5, Noe as modified discloses artificial heart valve prosthesis according to claim 4, wherein the flap is sutured at the second window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 (through hole) and therefore the flap is sutured “at” the second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online synonyms for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim, wherein each of the hinge sheets is at least partially arranged between the commissure and the flap (see annotated flap and hinge sheet in Figures 18A-18E below). This embodiment of Noe fails to disclose sutured by a suture thread successively passed through the main segment of the leaflet, the second window, the through hole and the trailing portion of the flap. Another embodiment of Noe teaches by a suture thread successively passed through the main segment of the leaflet, the second window, the through hole and the trailing portion of the flap (see annotated main segment, second window, through hole, and trailing portion in Figure 11E below). PNG media_image6.png 350 600 media_image6.png Greyscale Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have a suture thread successively passed through the main segment of the leaflet, the second window, the through hole and the trailing portion of the flap, as this method distributes strains along the length of the commissures, thereby reducing tearing or strain propagation through the tissue as taught by Noe (see paragraph [0130]). Regarding Claim 6, Noe as modified discloses the artificial heart valve prosthesis according to claim 2, wherein in a circumferential direction of the stent, edges of the through hole are coincident with the edge of the second window (see Figures 15A-15B above). Although not required due to the “or” clause, the embodiment of the hinge sheet 1515 has a through hole that is shaped the same as the second window (see annotated through hole in Figure 15B above, see also second window in 18E above). Since the hinge sheet of Noe as modified has this through hole, as modified by claim 2 above, it would have been obvious to one of ordinary skill to have the limitation wherein in a circumferential direction of the stent the edges of the through hole are lateral to edge of the second window, Regarding Claim 7, Noe as modified discloses the artificial heart valve prosthesis according to claim 2, wherein that the flap is provided with an engagement notch on a side thereof proximate an inflow end of the stent, wherein the engagement notch is located at a junction of the flap with the main segment (see annotated flap and notch in Figure 21 below, see also paragraph [0128]) and is configured to engage the through hole and the second window (see annotated flap being inserted into second window in Figure 18B below, and see Figure 15B and 15C showing the flaps inserted into the through hole, as the hinge sheet 1818 is modified by this embodiment to include this through hole for passage of the flaps, showing that this notch could “engage” the second window and through hole since the flap is inserted into both). PNG media_image7.png 278 606 media_image7.png Greyscale Regarding Claim 8, Noe as modified discloses the artificial heart valve prosthesis according to claim 2, wherein the commissure is further provided with a third window, wherein the third window is located on a side of the second window proximate an inflow end of the stent (see annotated third window in Figure 18E above), wherein the hinge sheet is sutured at the third window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 and therefore the flap is sutured “at” the first window and second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim. Regarding Claim 9, Noe as modified discloses the artificial heart valve prosthesis according to claim 1, wherein the second window is delimited by side support arms arranged circumferentially around the stent (see side arms annotated Figure 18E above), wherein each of the flaps comprises a head portion, a middle portion and a trailing portion, which are sequentially joined (see annotated head, middle, and trailing portion in Figures 18B and 18D below), wherein the head portion is inserted in the through hole (see annotated head portion being inserted into second window in Figure 18B below, and see Figure 15B and 15C showing the flaps inserted into the through hole, as the hinge sheet 1818 is modified by this embodiment to include this through hole for passage of the flaps), wherein the middle portion extends over the outer surface (see annotated middle portion and outer surface in Figure 18B below), an outer side face and an inner surface of the side support arm (see annotated middle portion in Figure 18B below, outer side face, and inner surface in Figure 18B below) and wherein the trailing portion overlaps a portion of the main segment in the leaflet (see annotated trailing portion in Figure 18B below, the trailing portion defined as the rest of the flap of the leaflet until the main segment in the leaflet, see also paragraph [0133] denoting that 1822a,b are the arms of the leaflets inside of the stent). PNG media_image8.png 588 833 media_image8.png Greyscale Regarding Claim 10, Noe as modified discloses artificial heart valve prosthesis according to claim 9, wherein the flap is sutured at the second window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 (through hole) and therefore the flap is sutured “at” the second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online synonyms for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim, wherein each of the hinge sheets is at least partially arranged between the commissure and the flap (see annotated flap and hinge sheet in Figures 18A-18E below). This embodiment of Noe fails to disclose sutured by a suture thread successively passed through the main segment of the leaflet, the second window, and the trailing portion of the flap. Another embodiment of Noe teaches by a suture thread successively passed through the main segment of the leaflet, the second window, and the trailing portion of the flap (see annotated main segment, second window, through hole, and trailing portion in Figure 11E below). PNG media_image6.png 350 600 media_image6.png Greyscale Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have a suture thread successively passed through the main segment of the leaflet, the second window, and the trailing portion of the flap, as this method distributes strains along the length of the commissures, thereby reducing tearing or strain propagation through the tissue as taught by Noe (see paragraph [0130]). Regarding Claim 11, Noe discloses an artificial heart valve prosthesis, comprising: a stent comprising at least two commissures spaced circumferentially around the stent (see annotated stent and commissures in Figure 10 below), wherein the commissure is provided with a second window (see annotated second window in Figure 18E below); hinge sheets at least partially covering an outer surface of the commissure and provided with a through hole (see annotated outer surface and through hole in Figure 18 B below); and at least two leaflets arranged circumferentially around the stent (see annotated leaflets in Figure 10 below), wherein each of the leaflets comprises a main segment and flaps arranged on opposite circumferential sides of the main segment (see annotated main segment in Figure 10 below and flaps in Figure 18E below), wherein the main segment is disposed on an inner side of the stent (see annotated main segment in Figure 10 below), wherein the flap is passed through the second window (see annotated flap and second window in Figure 18B below), wherein the hinge sheet is sutured at the second window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 (through hole) and therefore the flap is sutured “at” the second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online synonyms for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim, wherein each of the hinge sheets is at least partially arranged between the commissure and the flap (see annotated flap and hinge sheet in Figures 18A-18E below). PNG media_image4.png 588 1280 media_image4.png Greyscale This embodiment of Noe fails to disclose further comprising wherein the flap of the leaflet passes through the through hole, therefore having the flap cover at least a part of an outer surface of the hinge sheet, Another embodiment of Noe discloses another variation of a hinge sheet (see annotated hinge sheet 1515 in Figures 15B and 15C). This embodiment of Noe teaches wherein the hinge sheet is provided with a through hole for passage therethrough of the flap, therefore having the flap cover at least a part of an outer surface of the hinge sheet (see annotated flaps and through hole in Figures 15B and 15C). PNG media_image3.png 561 419 media_image3.png Greyscale Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention for the hinge sheet 1818 to have the through hole of 1515, thereby having a through hole for passage therethrough of the flap, and therefore having the flap covers at least a part of an outer surface of the hinge sheet, as by doing so would evenly distribute high stress areas of leaflet along the length of strut (see paragraph [0132]) and since it is disclosed in Noe that combinations of different embodiments would be apparent those of skill in the art upon reviewing the above description (see paragraph [0153]). Regarding Claim 12, Noe as modified discloses the artificial heart valve prosthesis according to claim 11, wherein the second window is delimited by side support arms arranged circumferentially around the stent (see side arms annotated Figure 18E above), wherein: the hinge sheet at least partially covers an outer surface, an outer side face and an inner surface of the side support arm (see hinge sheet in Figure 18A and 18D covering the entirety of the second window side arms from the view of the outside of the frame), and each of the flaps comprises a head portion, a middle portion and a trailing portion, which are sequentially joined (see annotated head, middle, and trailing portion in Figures 18B and 18D below), wherein the head portion is inserted in the second window and the through hole (see annotated head portion being inserted into second window in Figure 18B below, and see Figure 15B and 15C showing the flaps inserted into the through hole, as the hinge sheet 1818 is modified by this embodiment to include this through hole for passage of the flaps), wherein the middle portion extends over the outer surface (see annotated middle portion and outer surface in Figure 18B below), the outer side face and the inner surface of the side support arm so as to wrap a portion of the hinge sheet arranged on the side support arm (see annotated middle portion in Figure 18B below, outer side face, and inner surface in Figure 18B below) and wherein the trailing portion overlaps a portion of the main segment in the leaflet (see annotated trailing portion in Figure 18B below, the trailing portion defined as the rest of the flap of the leaflet until the main segment in the leaflet, see also paragraph [0133] denoting that 1822a,b are the arms of the leaflets inside of the stent). PNG media_image5.png 588 844 media_image5.png Greyscale Regarding Claim 13, Noe as modified discloses artificial heart valve prosthesis according to claim 12, wherein the flap is sutured at the second window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 (through hole) and therefore the flap is sutured “at” the second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online synonyms for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim, wherein each of the hinge sheets is at least partially arranged between the commissure and the flap (see annotated flap and hinge sheet in Figures 18A-18E below). This embodiment of Noe fails to disclose sutured by a suture thread successively passed through the main segment of the leaflet, the second window, the through hole and the trailing portion of the flap. Another embodiment of Noe teaches by a suture thread successively passed through the main segment of the leaflet, the second window, the through hole and the trailing portion of the flap (see annotated main segment, second window, through hole, and trailing portion in Figure 11E below). PNG media_image6.png 350 600 media_image6.png Greyscale Therefore, it would have been obvious to one of ordinary skill in the art before the effective filing date of the invention to have a suture thread successively passed through the main segment of the leaflet, the second window, the through hole and the trailing portion of the flap, as this method distributes strains along the length of the commissures, thereby reducing tearing or strain propagation through the tissue as taught by Noe (see paragraph [0130]). Regarding Claim 14, Noe as modified discloses the artificial heart valve prosthesis according to claim 11, wherein in a circumferential direction of the stent, edges of the through hole are coincident with the edge of the second window (see Figures 15A-15B above). Although not required due to the “or” clause, the embodiment of the hinge sheet 1515 has a through hole that is shaped the same as the second window (see annotated through hole in Figure 15B above, see also second window in 18E above). Since the hinge sheet of Noe as modified has this through hole, as modified by claim 2 above, it would have been obvious to one of ordinary skill to have the limitation wherein in a circumferential direction of the stent the edges of the through hole are lateral to edge of the second window, Regarding Claim 15, Noe as modified discloses the artificial heart valve prosthesis according to claim 11, wherein that the flap is provided with an engagement notch on a side thereof proximate an inflow end of the stent, wherein the engagement notch is located at a junction of the flap with the main segment (see annotated flap and notch in Figure 21 below, see also paragraph [0128]) and is configured to engage the through hole and the second window (see annotated flap being inserted into second window in Figure 18B below, and see Figure 15B and 15C showing the flaps inserted into the through hole, as the hinge sheet 1818 is modified by this embodiment to include this through hole for passage of the flaps, showing that this notch could “engage” the second window and through hole since the flap is inserted into both). PNG media_image7.png 278 606 media_image7.png Greyscale Regarding Claim 16, Noe as modified discloses the artificial heart valve prosthesis according to claim 11, wherein the commissure is further provided with a third window, wherein the third window is located on a side of the second window proximate an inflow end of the stent (see annotated third window in Figure 18E above), wherein the hinge sheet is sutured at the third window (see paragraph [0133], Noe discloses the flap is sutured into the holes 1819 and therefore the flap is sutured “at” the first window and second window). The term “at” is interpreted broadly, meaning “along”, “adjacent”, or “alongside” (see Merriam Webster Online for “at”; since the suture passes through holes “at” or adjacent to the first window and second window, the prior art reads on the claim. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. US 20220233307 A1: This reference discloses stent with leaflets inside of the stent, and commissures with an aperture around the body of the stent. US 20180021127 A1: This reference discloses stent with leaflets inside of the stent, and commissures with multiple apertures around the body of the stent. Any inquiry concerning this communication or earlier communications from the examiner should be directed to PARIS MARIE BLASS whose telephone number is (703)756-5375. The examiner can normally be reached Monday - Thursday 9 a.m. - 7 p.m. ET. 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, Melanie Tyson can be reached at 571-272-9062. 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. /PARIS MARIE BLASS/Examiner, Art Unit 3774 /SARAH W ALEMAN/Primary Examiner, Art Unit 3774
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Prosecution Timeline

Jun 09, 2023
Application Filed
Feb 02, 2026
Non-Final Rejection — §102, §103 (current)

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Prosecution Projections

1-2
Expected OA Rounds
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Grant Probability
99%
With Interview (+47.4%)
3y 9m
Median Time to Grant
Low
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