Prosecution Insights
Last updated: April 19, 2026
Application No. 18/507,504

ENZYME VARIANTS AND USES THEREOF

Final Rejection §DP§Other
Filed
Nov 13, 2023
Examiner
EPSTEIN, TODD MATTHEW
Art Unit
1652
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Samsara Eco Pty Limited
OA Round
4 (Final)
60%
Grant Probability
Moderate
5-6
OA Rounds
2y 11m
To Grant
99%
With Interview

Examiner Intelligence

Grants 60% of resolved cases
60%
Career Allow Rate
324 granted / 541 resolved
At TC average
Strong +45% interview lift
Without
With
+44.6%
Interview Lift
resolved cases with interview
Typical timeline
2y 11m
Avg Prosecution
44 currently pending
Career history
585
Total Applications
across all art units

Statute-Specific Performance

§101
6.4%
-33.6% vs TC avg
§103
31.0%
-9.0% vs TC avg
§102
15.9%
-24.1% vs TC avg
§112
29.8%
-10.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 541 resolved cases

Office Action

§DP §Other
DETAILED ACTION All objections and rejections stated in prior Office Actions are withdrawn unless restated below. 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 . Priority A petition decision from International Patent Legal Administration dated 12/09/2025 state the following regarding receipt of a certified copy of the foreign priority application (AU2021901431) as required by 37 CFR 1.55(f): PNG media_image1.png 31 438 media_image1.png Greyscale Specification The disclosure is objected to because of the following informalities: The specification is objected to for reciting improper priority information in para. [0001]. The latest filing receipt dated 11/14/2024 indicates: PNG media_image2.png 39 489 media_image2.png Greyscale Applicant’s latest Application Data Sheet dated 11/12/2024 claims the flowing priority: PNG media_image3.png 253 750 media_image3.png Greyscale However, para. [0001] improperly indicates continuation priority to PCT/AU2022/050455. Appropriate correction is required. Duplicate Claims Applicant is advised that should claim 78 be found allowable, claim 79 will be objected to under 37 CFR 1.75 as being a substantial duplicate thereof. When two claims in an application are duplicates or else are so close in content that they both cover the same thing, despite a slight difference in wording, it is proper after allowing one claim to object to the other as being a substantial duplicate of the allowed claim. See MPEP § 608.01(m). Claims 78 is dependent from a base claim while claim 79 is an independent claim. However, both claims have the same scope of a polypeptide having MHETase activity identical comprising one of SEQ ID NOS: 73-78. Double Patenting The nonstatutory double patenting rejection is based on a judicially created doctrine grounded in public policy (a policy reflected in the statute) so as to prevent the unjustified or improper timewise extension of the “right to exclude” granted by a patent and to prevent possible harassment by multiple assignees. A nonstatutory double patenting rejection is appropriate where the conflicting claims are not identical, but at least one examined application claim is not patentably distinct from the reference claim(s) because the examined application claim is either anticipated by, or would have been obvious over, the reference claim(s). See, e.g., In re Berg, 140 F.3d 1428, 46 USPQ2d 1226 (Fed. Cir. 1998); In re Goodman, 11 F.3d 1046, 29 USPQ2d 2010 (Fed. Cir. 1993); In re Longi, 759 F.2d 887, 225 USPQ 645 (Fed. Cir. 1985); In re Van Ornum, 686 F.2d 937, 214 USPQ 761 (CCPA 1982); In re Vogel, 422 F.2d 438, 164 USPQ 619 (CCPA 1970); In re Thorington, 418 F.2d 528, 163 USPQ 644 (CCPA 1969). A timely filed terminal disclaimer in compliance with 37 CFR 1.321(c) or 1.321(d) may be used to overcome an actual or provisional rejection based on nonstatutory double patenting provided the reference application or patent either is shown to be commonly owned with the examined application, or claims an invention made as a result of activities undertaken within the scope of a joint research agreement. See MPEP § 717.02 for applications subject to examination under the first inventor to file provisions of the AIA as explained in MPEP § 2159. See MPEP § 2146 et seq. for applications not subject to examination under the first inventor to file provisions of the AIA . A terminal disclaimer must be signed in compliance with 37 CFR 1.321(b). The filing of a terminal disclaimer by itself is not a complete reply to a nonstatutory double patenting (NSDP) rejection. A complete reply requires that the terminal disclaimer be accompanied by a reply requesting reconsideration of the prior Office action. Even where the NSDP rejection is provisional the reply must be complete. See MPEP § 804, subsection I.B.1. For a reply to a non-final Office action, see 37 CFR 1.111(a). For a reply to final Office action, see 37 CFR 1.113(c). A request for reconsideration while not provided for in 37 CFR 1.113(c) may be filed after final for consideration. See MPEP §§ 706.07(e) and 714.13. The USPTO Internet website contains terminal disclaimer forms which may be used. Please visit www.uspto.gov/patent/patents-forms. The actual filing date of the application in which the form is filed determines what form (e.g., PTO/SB/25, PTO/SB/26, PTO/AIA /25, or PTO/AIA /26) should be used. A web-based eTerminal Disclaimer may be filled out completely online using web-screens. An eTerminal Disclaimer that meets all requirements is auto-processed and approved immediately upon submission. For more information about eTerminal Disclaimers, refer to www.uspto.gov/patents/apply/applying-online/eterminal-disclaimer. Claims 49-70 and 78-82 (all pending claims) are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1, 4-19, 36-37, 40, 42-43, 47 and 48 of copending Application No. 18/783,325 in view of Uniprot, Accession No. A0A0K8P8E7, 2016, www.uniprot.org (see IDS dated 03/03/2025) and CN109402037A (see IDS dated 11/13/2023). An machine translation of CN109402037A was previously provided and cited below. Copending claim 1 recites: PNG media_image4.png 489 676 media_image4.png Greyscale SEQ ID NO: 1 of the copending claims is identical to recited SEQ ID NO: 1, positions 20-603. As such, the position numbering stated in the copending claims is the same as the numbering in the pending/rejected claims. For this reason, copending claim 1 anticipates the features of claims 49, 50, 52, 54, 56, and 58-61, wherein statement of “one or more positions” in the copending claims is directly understood to indicate substitution in all four positions recited. The features of claims 50, 53, 55 and 57 are anticipated by copending claims 5, 7, 9 and 11, respectively. Claims 62-65 are anticipated by copending claims 16-19, respectively. Claims 66-68 are anticipated by copending claims 36, 37 and 40, respectively. The features of claim 70 are anticipated by copending claim 43. Regarding claims 77-80, SEQ ID NO: 77 is SEQ ID NO: 1 embodying substitutions T159V, M192Y, Y503W and Y252F. Copending claim 17 is understood as directly indicating an enzyme identical to SEQ ID NO: 1 of the copending claims with substitutions T159V, M192Y, Y503W and Y252F. SEQ ID NO: 1 of the copending claims does not have the 19 amino acid residues N-terminal sequence required by recited SEQ ID NO: 77. However, the copending claims directly indicate and reference a “19 amino acid N-terminal signal sequence” wherein the identity of such 19 amino acid N-terminal signal sequence is known in the prior art as taught by Uniprot A0A0K8P8E7. Due to copending claim 1 directly reciting the “19 amino acid N-terminal signal sequence” an ordinarily skilled artisan at the time of filing would have been motivated to form an embodiment of copending claim 17 having the “19 amino acid N-terminal signal sequence” taught by Uniprot A0A0K8P8E7 present as to result in a MHETase polypeptide identical to SEQ ID NO: 77. An ordinarily skilled artisan at the time of filing would have been motivated to do this since the copending claims suggest the presence of such a signal peptide. Regarding claims 81 and 82, none of copending claims directly anticipate claims 81 and 82. CN 109402037 A (CN203) teaches a MHETase having substitutions relative to SEQ ID NO: 1 but not the substitutions recited in the claims. CN203, abstract, teaches “the gene engineering bacteria is by using a double plasmid expression mode or single plasmid expression mode of the gene fragment for expressing PET hydrolase and MHET hydrolase into host bacteria. The invention claims a gene engineering bacteria capable of expressing both PET hydrolase and MHET hydrolase and secreted into the extracellular.” The preceding is a teaching that it is well established in the prior art to express a MHET hydrolase with high sequence identity to SEQ ID NO: 1 through an encoding polynucleotide and to express the same MHET hydrolase into an extracellular medium that is a composition. As such, at the time of filing an ordinarily skilled artisan would have been motivated to form an embodiment of copending claim 17, including an embodiment MHETase identical to recited SEQ ID NO: 77 as discussed above, by forming a nucleotide encoding the same and expressing the same into a composition as taught by CN203 as to meet the features of copending claims 81-82. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Claims 49-70 and 78-82 (all pending claims) are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-51 of copending Application No. 19/106,607 in view of CN109402037A (see IDS dated 11/13/2023). A machine translation of CN109402037A was provided previously and cited below. Copending claims 1, 10, 21 and 29 directly recite an indicate a MHETase having recited SEQ ID NO: 1 (as SEQ ID NO: 1 of the copending claims) with substitutions T159V, M192Y, Y503W and Y252F that is a polypeptide identical to recited SEQ ID NO: 77. The copending claims anticipate claims 49, 52-63, and 77-82 wherein the copending claims recite a method of hydrolysing MHET. Regarding claims 50-51 and 64-64, copending claim 27 directly indicates the substitutions N156G, T159V, M192Y and Y503 of the same SEQ ID NO: 1 as to anticipate claims 50-51 and 64-64. Regarding claims 66-68 and 81-82, CN203, abstract, teaches “the gene engineering bacteria is by using a double plasmid expression mode or single plasmid expression mode of the gene fragment for expressing PET hydrolase and MHET hydrolase into host bacteria. The invention claims a gene engineering bacteria capable of expressing both PET hydrolase and MHET hydrolase and secreted into the extracellular.” The preceding is a teaching that it is well established in the prior art to express a MHET hydrolase with high sequence identity to SEQ ID NO: 1 through an encoding polynucleotide and to express the same MHET hydrolase into an extracellular medium that is a composition. As such, at the time of filing an ordinarily skilled artisan would have been motivated to form an embodiment of the copending claims, including an embodiment MHETase identical to recited SEQ ID NO: 77 as discussed above, by forming a nucleotide encoding the same and expressing the same into a composition as taught by CN203 as to meet the features of copending claims 66-68 and 81-82. Regarding claim 70, CN203, pg. 5, further teaches “the MHET hydrolase from the PET plastic oligomer or oligomer state degradation is phthalic acid and glycol monomer, so as to completely degrade the PET plastic.” The preceding is understood that as a direct teaching that PET and/or MHET can be exposed to any known enzyme with high identity to recited SEQ ID NO: 1 and conditions to convert MHET to terephthalate and ethylene glycol wherein “glycol monomer” is understood as a direct reference to ethylene glycol (liberated by hydrolysis of 2-hydroxyethyl group of MHET). This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Response to arguments PNG media_image5.png 193 676 media_image5.png Greyscale Matters of petition are not addressed by the Examiner. The petition decision dated 12/09/2025 (the only petition decision in the file wrapper issued after 03/03/2025) does not address any issues regarding a priority claim under 35 U.S.C. 120 to PCT/AU20222/050455. Further, the applicant claims CIP priority to PCT/AU20222/050455 and Examiner is providing a notification that the first paragraph of the application is inconsistent with the priority claim. Priority claims are made in the ADS (see 37 CFR 1.76) wherein the latest filed IDS dated 11/12/2024 claims CIP priority to PCT/AU20222/050455. No priority claim can be recognized that is not claimed in the latest ADS and appearing on the latest filing receipt. An ADS “must be submitted when required by § 1.55 or 1.78 to claim priority to or the benefit of a prior-filed application under 35 U.S.C. 119, 120, 121, 365, or 386.” 37 CFR 1.76(a). “The most recent application data sheet will govern with respect to foreign priority (§ 1.55 ) or domestic benefit (§ 1.78 ) claims.” 37 CFR 1.76(d)(1)(i). “The application data sheet, if provided, is considered part of the application. 37 CFR 1.76(b)(5) states that providing this information in the application data sheet constitutes the specific reference required by 35 U.S.C. 119(e) or 120, and 37 CFR 1.78. A specific reference to the earlier application(s) is no longer required to be made in the specification, such as in the first sentence(s) thereof. The continuity data for the patent front page will be taken from the application data sheet. No continuity data will be included in the first sentence(s) of the specification, unless applicant separately provides it there.” MPEP 601.05(a)(I). Statement regarding prior art Yoshida et al. (A bacterium that degrades and assimilates poly(ethylene terephthalate), Science 351, 2016: 1196-99) discusses I. sakainesis 201-F6, the source organism of recited SEQ ID NO: 1, and “here are currently few known examples of esterases, lipases, or cutinases that are capable of hydrolyzing PET” and related compounds such as MHET. Yoshida, page 1197, right col. Uniprot, accession no. A0A2H4I8W2, 2020, www.uniprot.org, reports a Chlorogenate esterase or tannase having about 70% identity to SEQ ID NO: 1 with a substitution N156R relative thereto. While necessarily a related esterase to recited SEQ ID NO: 1, at this time no credible assertion can be made that the enzyme disclosed by Uniprot A0A2H4I8W2 has MHETase activity as required by the claims. Conclusion No new rejections are made in this Office Action. However, as far as it may nevertheless be asserted that a rejection above is new: Applicant's amendment necessitated the new ground(s) of rejection presented in this Office action. Accordingly, THIS ACTION IS MADE FINAL. See MPEP § 706.07(a). 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 TODD M EPSTEIN whose telephone number is (571)272-5141. The examiner can normally be reached Mon-Fri 9:00a-5:30p. 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, Robert Mondesi can be reached at (408) 918-7584. 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. /TODD M EPSTEIN/Primary Examiner, Art Unit 1652
Read full office action

Prosecution Timeline

Nov 13, 2023
Application Filed
Apr 18, 2024
Non-Final Rejection — §DP, §Other
Jul 17, 2024
Applicant Interview (Telephonic)
Jul 24, 2024
Response Filed
Jul 27, 2024
Examiner Interview Summary
Nov 13, 2024
Final Rejection — §DP, §Other
Jan 30, 2025
Interview Requested
Feb 06, 2025
Applicant Interview (Telephonic)
Feb 08, 2025
Examiner Interview Summary
Mar 03, 2025
Request for Continued Examination
Mar 09, 2025
Response after Non-Final Action
Apr 05, 2025
Non-Final Rejection — §DP, §Other
May 16, 2025
Interview Requested
May 27, 2025
Applicant Interview (Telephonic)
May 30, 2025
Examiner Interview Summary
Jun 17, 2025
Response Filed
Feb 25, 2026
Final Rejection — §DP, §Other (current)

Precedent Cases

Applications granted by this same examiner with similar technology

Patent 12600974
GENETICALLY ENGINEERED MICROORGANISM CAPABLE OF GROWING ON FORMATE, METHANOL, METHANE OR CO2
2y 5m to grant Granted Apr 14, 2026
Patent 12595467
DNA POLYMERASE AND DNA POLYMERASE DERIVED 3'-5'EXONUCLEASE
2y 5m to grant Granted Apr 07, 2026
Patent 12595495
Methods Of Producing Omega-Hydroxylated Fatty Acid Derivatives
2y 5m to grant Granted Apr 07, 2026
Patent 12590273
STABILIZED GLYCOSIDE HYDROLASE VARIANTS
2y 5m to grant Granted Mar 31, 2026
Patent 12577542
MONOMER POLYPEPTIDE HAVING HYDROGENASE ACTIVITY, IN PARTICULAR RECOMBINANT MONOMER POLYPEPTIDE HAVING HYDROGENASE ACTIVITY
2y 5m to grant Granted Mar 17, 2026
Study what changed to get past this examiner. Based on 5 most recent grants.

AI Strategy Recommendation

Get an AI-powered prosecution strategy using examiner precedents, rejection analysis, and claim mapping.
Powered by AI — typically takes 5-10 seconds

Prosecution Projections

5-6
Expected OA Rounds
60%
Grant Probability
99%
With Interview (+44.6%)
2y 11m
Median Time to Grant
High
PTA Risk
Based on 541 resolved cases by this examiner. Grant probability derived from career allow rate.

Sign in with your work email

Enter your email to receive a magic link. No password needed.

Personal email addresses (Gmail, Yahoo, etc.) are not accepted.

Free tier: 3 strategy analyses per month