Prosecution Insights
Last updated: April 19, 2026
Application No. 18/146,497

TITANIUM IMPLANT WITH SURFACE COATING IN CRATER-LIKE POROUS SHAPE AND PREPARATION METHOD THEREOF, AND IMPLANT MATERIAL

Non-Final OA §103
Filed
Dec 27, 2022
Examiner
WITTENBERG, STEFANIE S
Art Unit
1795
Tech Center
1700 — Chemical & Materials Engineering
Assignee
Shanghai Ruizhikang Medical Technology Co. Ltd.
OA Round
3 (Non-Final)
54%
Grant Probability
Moderate
3-4
OA Rounds
3y 2m
To Grant
73%
With Interview

Examiner Intelligence

Grants 54% of resolved cases
54%
Career Allow Rate
361 granted / 667 resolved
-10.9% vs TC avg
Strong +19% interview lift
Without
With
+19.3%
Interview Lift
resolved cases with interview
Typical timeline
3y 2m
Avg Prosecution
59 currently pending
Career history
726
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
17.6%
-22.4% vs TC avg
§112
29.2%
-10.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 667 resolved cases

Office Action

§103
DETAILED ACTION Status of Claims Claims 1-4, 6-12 and 14-20 are pending. Claims 9-12 and 14-20 are withdrawn from consideration. Claims 5 and 13 are cancelled. 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 . 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and the fee set forth in 37 CFR 1.17(e) has been timely paid, the finality of the previous Office action has been withdrawn pursuant to 37 CFR 1.114.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 23 January 2026 has been entered. Status of Objections and Rejections All rejections from the previous Office action are withdrawn in view of Applicant’s amendment. New grounds of rejection are necessitated by amendment. 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. Claim(s) 1-2, 4 and 7-8 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gorhe et al. (US 2018/0280143), in view of Wei et al. (CN 103083099) and in view of Gao et al. (CN 115012014). Regarding claims 1 and 2, Gorhe discloses a method of modifying a porous surface of implants including titanium (title, [0004]) (= a preparation method of a titanium implant with a surface coating in a crater-like porous shape), comprising the following steps: Prior to micro-arc oxidation, a porous medical device can optionally be cleaned, degreased, and/or polished [0066]-[0067] (= subjecting a titanium substrate to polishing and cleaning to obtain a pretreated titanium substrate); and Carrying out micro-arc oxidation to form pores [0012] using an iron cathode [0073] and a sodium phosphate electrolyte [0069] (= conducting micro-arc oxidation using the pretreated titanium substrate obtained in the first step as an anode and iron as a cathode in a sodium-phosphate containing electrolyte to obtain the titanium implant with a surface coating in a crater-like porous shape). Gorhe discloses potassium hydroxide (165 g/L) may be included in the electrolyte [0069]. Gorhe discloses an electrolyte temperature including of about 10 ℃ or less [0012]. Regarding the claimed “crater-like”, the porous structure of Gorhe reads on the claimed “crater-like” given the bowl-shape pores (Figure 5). Regarding the claimed “polishing, cleaning and first drying in sequence” Gorhe discloses cleaning and polishing [0066]. Gorhe does not explicitly disclose a first drying, however, it would have been obvious to one of ordinary skill in the art to perform a first drying after cleaning and polishing to prepare the substrate for subsequent processing steps. Moreover, Gorhe discloses additional drying steps [0067]. Further, selection of any order of performing process steps is prima facie obvious in the absence of new or unexpected results. The concentration ([KOH]) and temperature of Gorhe fall outside the claimed range, however, differences in concentration or temperature will not support the patentability of subject matter encompassed by the prior art unless there is evidence indicating such concentration or temperature is critical. Where 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. Gorhe discloses the frequency, however, the frequency is not provided as a duty cycle percentage [0075]. Wei discloses a titanium implant (title) including TA2 (as applied to claim 2, [0029]) and treating the substrate comprising polishing, cleaning, drying the substrate [0032] and then subsequently performing micro-arc oxidation [0033] with a duty cycle of 4-20 % [0034] to produce a porous structure [0051]. Wei additionally discloses the use of iron as the counter electrode [0047]. Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to produce a method comprising a duty cycle of 3-5% because in the same or similar field of endeavor, Wei discloses a workable duty cycle including 4-20 % which overlaps with the claimed range therefore a prima facie case of obviousness exists. The methods of Gorhe and Wei overlap in several aspects and it would have been obvious to combine their method parameters. Moreover, there does not appear to be any criticality to the claimed duty cycle range. To further address the electrolyte temperature, Wei discloses the electrolyte temperature comprising 10-40 ℃ [0011], [0034] which overlaps the claimed range therefore a prima facie case of obviousness exists. Wei discloses the electrolyte comprising sodium hydroxide with a concentration of 1- 25 g/L [0033], [0046]. Gorhe and Wei fail to disclose the electrolyte comprising glycerol. Wei discloses sodium hydroxide and Gorhe discloses potassium hydroxide, but the concentration of potassium hydroxide is outside the claimed range. In the same or similar field of endeavor, Gao discloses forming an oxide film on the surface of a metal workpiece [n0001] optionally aluminum, titanium or magnesium [n0004] comprising micro-arc oxidation with a duty cycle of 5% [n00034] and a phosphate based electrolyte comprising sodium hydroxide or potassium hydroxide as the conductive agent in the amount of 1 to 10 g/L and glycerol as the stabilizer [n0014]. The range of potassium hydroxide overlaps the claimed range. Gao teaches that most scholars have completed the design and preparation of ceramic film microstructures and phase composition by controlling and optimizing electrical parameters including voltage, current density, duty cycle, frequency time and electrolyte including components, concentration, etc. [n0006]. Gao discloses a range of duty cycle including 5-90% [n0016]. Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to produce a method comprising potassium hydroxide and glycerol because Gao discloses including potassium hydroxide in an amount of 1 to 10 g/L as a conductive agent and glycerol as a stabilizer. Adjusting the concentration of Gorhe would have been an obvious engineering design choice in order to control the conductivity. Regarding claim 4, Wei discloses using acetone, ethanol and deionized water to ultrasonically clean [0009], [0045]. Wei discloses the use of 95% ethanol and not the claimed absolute ethanol, however, it would have been obvious to one of ordinary skill in the art to utilize an absolute ethanol in order to achieve improved cleaning using a more pure solvent. Regarding claim 7, Wei discloses performing micro arc oxidation for 5-15 minutes [0011]. Regarding claim 8, Wei discloses rinsing and drying after micro-arc oxidation [0035]. Claim(s) 3 and 6 is/are rejected under 35 U.S.C. 103 as being unpatentable over Gorhe et al. (US 2018/0280143), in view of Wei et al. (CN 103083099), in view of Gao et al. (CN 115012014) and in further view of Wang et al. (CN 114921832). Regarding claim 3, Gorhe in view of Wei and Gao disclose polishing as a pre-treatment step. The combination is silent in regards to the process parameters for polishing therefore in order to produce the method of Gorhe in view of Wei and Gao one of ordinary skill in the art would necessarily look to the art for workable polishing parameters and arrive at a reference such as Wang. In the same or similar field of micro-arc oxidation of a titanium surface, Wang discloses polishing as a pre-treatment process including polishing steps using 400#, 600#, 800#, 1200# sandpaper in sequence [n0009]. Before the effective filing date of the claimed invention, it would have been obvious to one of ordinary skill in the art to utilize the polishing sequence of Wang for carrying out the method of Gorhe in view of Wei to produce the same or similar result of a polished pre-treated titanium surface. Although Wang does not disclose 2000# and 3000# sandpaper, selection of the coarseness of sandpaper would have been an obvious engineering design choice for producing a polished titanium surface. Regarding claim 6, Wei discloses a frequency of 200-1000 Hz [0011] which overlaps the claimed range therefore a prima facie case of obviousness exists. Gorhe and Wei disclose the units of micro-arc in volts and not the claimed amps. Wang discloses an oxidation current of 2-6 A/dm2 [n0011]. Although the units are provided in current density, they are close enough that one of ordinary skill in the art would expect the same or similar predictable result of micro-arc oxidation. Response to Arguments Applicant's arguments filed 23 January 2026 have been fully considered. On page 2 the remarks are directed towards the claimed potassium hydroxide and its concentration. The teachings of Gao et al. are herein cited for disclosing KOH in the amount of 1- 25 g/L [0033], [0046]. Gao et al. explicitly state that KOH is used as a conductive agent therefore the adjustment of KOH would have been obvious to one of ordinary skill in the art. On pages 2-4 the remarks are directed towards the experimental results obtained by adjusting the KOH concentration. The experimental results are acknowledged. The concentration range of Gao overlaps the claimed range therefore a prima facie case of obviousness exists. Although the experimental results indicate differences between the oxide surface, there does not appear to be any critical result produced by adjusting the concentration. One or ordinary skill in the art would understand that the oxide surface topology for example is altered by either adjusting the micro-arc oxidation parameters or electrolyte parameters as described above in the teachings of Gao et al. On pages 4-5 the remarks are directed towards the claimed temperature. Wei discloses an overlapping temperature range as stated above. On pages 5-6 the remarks are directed towards the Wang reference and state that Wang’s method produces a smooth and flat coating and therefore does not disclose the claimed invention. The Examiner respectfully disagrees with this analysis. Wang is relied upon for being in the same or similar field of micro-arc oxidation, however, Wang’s inclusion in the grounds of rejection is directed towards polishing parameters and therefore the specific micro-arc oxidation features do not appear to be directly related to the combination of prior art. The Declaration dated 23 December 2025 is acknowledged. The subject matter of the Declaration is addressed above in regards to the concentration. Conclusion The prior art made of record and not relied upon is considered pertinent to applicant's disclosure. CN105603488 glycerol, KOH, temperature Any inquiry concerning this communication or earlier communications from the examiner should be directed to STEFANIE S WITTENBERG whose telephone number is (571)270-7594. The examiner can normally be reached Monday - Friday, 7:00 am -4:00 pm EST. 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, Luan Van can be reached at (571) 272-8521. 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. /Stefanie S Wittenberg/Primary Examiner, Art Unit 1795
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Prosecution Timeline

Dec 27, 2022
Application Filed
Jul 29, 2025
Non-Final Rejection — §103
Oct 14, 2025
Response Filed
Oct 23, 2025
Final Rejection — §103
Dec 23, 2025
Response after Non-Final Action
Jan 23, 2026
Request for Continued Examination
Jan 29, 2026
Response after Non-Final Action
Feb 09, 2026
Non-Final Rejection — §103 (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
54%
Grant Probability
73%
With Interview (+19.3%)
3y 2m
Median Time to Grant
High
PTA Risk
Based on 667 resolved cases by this examiner. Grant probability derived from career allow rate.

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