Prosecution Insights
Last updated: April 19, 2026
Application No. 18/269,256

PROCESS PROVIDING IMPROVED BASE OIL YIELD

Final Rejection §103§112
Filed
Jun 22, 2023
Examiner
NGUYEN, TAM M
Art Unit
1771
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Chevron U S A Inc.
OA Round
2 (Final)
78%
Grant Probability
Favorable
3-4
OA Rounds
2y 9m
To Grant
88%
With Interview

Examiner Intelligence

Grants 78% — above average
78%
Career Allow Rate
746 granted / 963 resolved
+12.5% vs TC avg
Moderate +11% lift
Without
With
+10.9%
Interview Lift
resolved cases with interview
Typical timeline
2y 9m
Avg Prosecution
68 currently pending
Career history
1031
Total Applications
across all art units

Statute-Specific Performance

§101
0.1%
-39.9% vs TC avg
§103
51.2%
+11.2% vs TC avg
§102
16.7%
-23.3% vs TC avg
§112
18.7%
-21.3% vs TC avg
Black line = Tech Center average estimate • Based on career data from 963 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 . Response to Amendment The rejection of claims 1-11 and 15 under 35 USC § 102(a)(2) by Freerks is withdrawn by the examiner in view of the amendment filed on 7/30/2025. A new Final Office Action is follows. 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 1-11 and 24 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 limitations “the base oil comprises XLN, LN and MN grades of base oil products” on the las line of claim 1 renders the claim indefinite because it is unclear if the base oil is produced from step b) or c). Claim 13 is indefinite because it is inconsistent with the limitations in claim 1 which stated that the medium wax cut is passed directly to a hydrodewaxing reactor while in claim 13, the medium wax cut is passed into a hydrotreating prior to the hydrodewaxing. Claim 24 is indefinite because it is inconsistent with the limitations in claim 16 which stated that the combined medium wax cuts is passed directly to a hydrodewaxing reactor while in claim 24, the combined medium wax cuts is passed into a hydrotreating prior to the hydrodewaxing. Claim Rejections - 35 USC § 103 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. 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. This application currently names joint inventors. In considering patentability of the claims the examiner presumes that the subject matter of the various claims was commonly owned as of the effective filing date of the claimed invention(s) absent any evidence to the contrary. Applicant is advised of the obligation under 37 CFR 1.56 to point out the inventor and effective filing dates of each claim that was not commonly owned as of the effective filing date of the later invention in order for the examiner to consider the applicability of 35 U.S.C. 102(b)(2)(C) for any potential 35 U.S.C. 102(a)(2) prior art against the later invention. Claims 1-11, 15-17, and 19-23 are rejected under 35 U.S.C. 103 as being unpatentable over Freerks et al. (US 2005/0183988 A1). Freerks discloses a process for preparing lubricant base oil. In this process, a waxy feed (10, 12, 28) is fractionated in a distillation column (11). This produces three fractions: a light wax and fuel fraction (13, 14), a middle wax fraction (24) with a boiling point of about 371–593° C, and a heavy unconverted wax fraction (26). The heavy fraction is passed to hydrocracking (23) and returned to the distillation column (11). Logically, the light wax fraction would have a boiling point below 371° C, while the heavy waxy fraction would have a boiling point above 593° C. The middle wax fraction (24) is then passed directly to hydrodewaxing (16) and hydrofinishing (18), and finally separated into several base oil products (20) and fuels (21). See [0017], [0018], [0025], [0031], [0035], [0036]; Fig.2. Freerks does not explicitly teach that the base oil product having XLN, LN, and MN grades of base oil, does not teach that the first and second medium fractions are combined and fed into the dewaxing step. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Freerks by having XLN, LN, and MN grades of base oil because of the similarities between the claimed process and the process of Freerks. It is within the level of one of skill in the art to produce a base oil having XLN, LN, and MN grades of base oil as claimed. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Freerks by combining both the first and second medium waxy fractions into the hydrodewaxing step because of the compositional similarities between the fractions. Claims 13, 14, 24 and 25 are rejected under 35 U.S.C. 103 as being unpatentable over Freerks as applied to claims 1-12 and 15-23 above, and further in view of Adams et al. (US 2006/0157384 A1). The process of Freerks is as discussed above. Freerks does not does not disclose that the medium wax fraction is hydrotreated prior to hydrodewaxing, and does not teach a dewaxing catalyst. Adams discloses the medium wax fraction is hydrotreated prior to hydrodewaxing which comprises a dewaxing catalyst. See [0014], [0018], [0028]. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Freerks by hydrotreating the medium fraction prior to hydrodewaxing as suggested by Adams to further remove contaminants. It would have been obvious to one having ordinary skill in the art before the effective filing date of the claimed invention to have modified the process of Freerks by utilizing a dewaxing catalyst as suggested by Adams to hydrodewax the medium fractions. Response to Arguments The argument that Freerks fails to disclose or suggest a medium wax cut directly feeding to a hydrodewaxing reactor is not persuasive because Freerks clearly teaches that the medium wax cut (24) is passed directly to hydrodewaxing unit 16. See figure 2. The argument that Freerks fails to disclose or suggest hydrotreating the (or combined) medium wax cut is not persuasive because the examiner relied upon Adams to teach the hydrotreating step. The argument that Freerks does not teach a base product comprising XLN, LN, and MN grades of base oil is not persuasive because the examiner maintains that because of the similarities between the claimed process and the process of Freerks, it is within the level of one of skill in the art to produce a base oil having XLN, LN, and MN grades of base oil as claimed. Conclusion 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 TAM M NGUYEN whose telephone number is (571)272-1452. The examiner can normally be reached Mon - Frid. 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, Prem C Singh can be reached on 571-273-6381. 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. /TAM M NGUYEN/Primary Examiner, Art Unit 1771
Read full office action

Prosecution Timeline

Jun 22, 2023
Application Filed
Jan 25, 2025
Non-Final Rejection — §103, §112
Jul 30, 2025
Response Filed
Oct 18, 2025
Final Rejection — §103, §112 (current)

Precedent Cases

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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
78%
Grant Probability
88%
With Interview (+10.9%)
2y 9m
Median Time to Grant
Moderate
PTA Risk
Based on 963 resolved cases by this examiner. Grant probability derived from career allow rate.

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