Prosecution Insights
Last updated: April 19, 2026
Application No. 18/038,661

METHOD FOR PRODUCING BONE REGENERATION MATERIAL HAVING COTTON-WOOL LIKE STRUCTURE

Final Rejection §103
Filed
May 24, 2023
Examiner
HAGOPIAN, CASEY SHEA
Art Unit
1617
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
Orthorebirth Co. Ltd.
OA Round
2 (Final)
54%
Grant Probability
Moderate
3-4
OA Rounds
3y 5m
To Grant
88%
With Interview

Examiner Intelligence

Grants 54% of resolved cases
54%
Career Allow Rate
304 granted / 558 resolved
-5.5% vs TC avg
Strong +33% interview lift
Without
With
+33.0%
Interview Lift
resolved cases with interview
Typical timeline
3y 5m
Avg Prosecution
50 currently pending
Career history
608
Total Applications
across all art units

Statute-Specific Performance

§101
1.4%
-38.6% vs TC avg
§103
40.9%
+0.9% vs TC avg
§102
14.8%
-25.2% vs TC avg
§112
25.5%
-14.5% vs TC avg
Black line = Tech Center average estimate • Based on career data from 558 resolved cases

Office Action

§103
DETAILED ACTION Receipt is acknowledged of applicant’s Amendment/Remarks filed 2/16/2026. 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 . Status of the Claims Claims 1, 7 and 9 have been amended. Claims 2 and 3 are cancelled. No claims are newly added. Accordingly, claims 1 and 4-10 remain pending in the application and are currently under examination. Withdrawn Objections/Rejections Applicant’s amendment renders the objections of claims 1, 7 and 9 moot. Specifically, the claims have been amended to remedy the minor informalities. Thus, said objections have been withdrawn. Applicant’s amendment renders the rejection under 35 USC 103 over Stark and Nelson moot. Specifically, the references do not teach or suggest the particular poor solvent, water. Thus, said rejection has been withdrawn. Maintained Rejections 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 and 4-10 are rejected under 35 U.S.C. 103 as being unpatentable over Stark et al. (US 2010/0196440 A1, Aug. 5, 2010, hereafter as “Stark”) in view of Nelson et al. (“Technique Paper for Wet-Spinning Poly(L-lactic acid) and Poly(DL-lactide-co-glycolide) Monofilament Fibers”, Tissue Engineering, Volume 9, Number 6, 2003, pp. 1323-1330, hereafter as “Nelson”) and Shah (USPN 6,020,004, Feb. 1, 2000, hereafter as “Shah”). The instant claims are drawn to a cotton-wool-like bone regenerating material produced from by using an improved wet spinning process, the cotton-wool like bone regenerating material is produced by the process of: preparing a spinning solution with a resin concentration of 10-20wt% in which calcium salt particles are dispersed by mixing the calcium salt particles of 50-80wt% and PDLLGA resin of 20-50wt% in a mixing container to form a mixture, and dissolving the mixture in acetone to form a dissolved mixture and stirring the dissolved mixture, and filling the spinning solution thus prepared in a syringe, injecting the spinning solution filled in the syringe into a collector container filled with a water by extruding the spinning solution from the outlet of an injection needle having a predetermined diameter of the syringe, wherein the spinning solution injected into the water is solidified into fibers by interdiffusion of desorption of acetone and penetration of the water, and the fibers solidified in the water are collected in cotton-wool like form by floating and depositing in the collector container without having adhesion between the fibers; and a method of making thereof. Regarding instant claims 1 and 4-10, Stark teaches fibrous compositions and implant materials for dental and bone applications and tissue engineering applications (abstract; [0060]). Stark describes a cotton-like material (Fig. 1c; [0022] and [0082]). Stark teaches said composition in the form of fibers comprising one or more biodegradable polymers and one or more biodegradable inorganic nanoparticles and optionally pharmaceutically active ingredients and/or proteins ([0029]). Stark teaches that copolymers of glycolic and lactic acid (including D-, L- or DL lactic acid) such as PLGA are particularly suitable as the degradable polymer ([0032]). Stark teaches that, in one embodiment, the biodegradable inorganic nanoparticles essentially consist of XRD-amorphous calcium phosphates including beta-tricalcium phosphate wherein up to 0.5 mass-% of the Ca-ions are replaced by silver which is present as Ag+ ([0038]; instant claims 4-6 and 8-10). Stark teaches that the fibers contain 1-80 mass-% nanoparticles, preferably 5-40 mass-% nanoparticles ([0040]). Stark teaches that the optional pharmaceutically active ingredients(s) can be included in amounts up to 5 mass-% and/or protein(s) can be included in amounts up to 1 mass-% ([0040]). The amounts taught by Stark imply that the degradable polymer can be in amounts of 20-99% if the optional components are not present. Stark further teaches dissolving the biodegradable polymer in a solvent (e.g., acetone), dispersing the nanoparticles in the dissolved polymer solution (stirring) and further subjecting the solution to a spinning process such as wet spinning ([0049], [0051], [0054] and [0078]). Stark also teaches loading the solution into a syringe and spraying the spinning solution into a collection tube ([0078]). While Stark teaches that copolymers of glycolic and lactic acid (including D-, L- or DL lactic acid) such as PLGA are particularly suitable as the degradable polymer ([0032]), Stark does not explicitly teaches PDLLGA. However, 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 select a copolymer of glycolic acid and DL-lactic acid (PDLLGA) with a reasonable expectation of success because Stark teaches a finite number of identified, predictable solutions. Stark does not explicitly teaches 50-80 wt% calcium salt particles and 20-50 wt% PDLLGA. However, MPEP 2144.05 states, “In the case where the claimed ranges ‘overlap or lie inside ranges disclosed by the prior art’ a prima facie case of obviousness exists”. Because the claimed ranges lie inside the ranges of calcium particles in an amount of 1-80 mass-% and polymer in an amount of 20-99% taught by Stark, a prima facie case of obviousness exists. Stark is silent to a spinning solution comprising a resin concentration of 10-20 wt% as well as a poor solvent. Nelson teaches wet-spinning poly(L-lactic acid) and poly(DL-lactic-co-glycolic acid) (PLGA/PDLLGA) monofilament fibers for tissue engineering scaffolds (abstract). Nelson teaches that PLGA was dissolved in a solvent at a concentration of 20 wt/v%, the polymer solution was loaded into a syringe and placed in a syringe pump, connected to needle dispensers, the needle tip was placed in a coagulation bath composed of a poor solvent for the polymer, and the fibers were extruded (page 1325, Materials and Methods; Fig. 1). Both Stark and Nelson are drawn to wet spinning PLGA polymer fibers for tissue engineering purposes, thus, 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 include a PLGA concentration of 20 wt% in Stark as suggested by Nelson with a reasonable expectation of success. A skilled artisan would have been motivated to do so because Nelson teaches that such a concentration is suitable for the method of wet spinning fibers. It would have also been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include a poor solvent in Stark as suggested by Nelson with a reasonable expectation of success because Nelson teaches that it is conventional to place the needle tip into a coagulation bath composed of a poor solvent for the polymer when forming fibers by wet spinning. Stark and Nelson are silent to the particular poor solvent, water (instant claim 1). Shah is directed to biodegradable microparticles for the sustained delivery of therapeutic drugs (title). Shah teaches that non-solvents (poor solvents) known for PLGA include water, hexane, ethanol, methanol, and carbon tetrachloride (col. 6, lines 5-11). The references are all drawn to compositions comprising PLGA, thus, it would have been prima facie obvious to one of ordinary skill in the art to include a poor solvent such as water or ethanol in the invention of Stark/Nelson as suggested by Shah with a reasonable expectation of success. A skilled artisan would have been motivated to do so because Nelson teaches that a poor solvent for PLGA is utilized in the wet spinning process and Shah teaches known poor solvents of PLGA. A skilled artisan would have reasonably expected that any known poor solvent of PLGA such as ethanol and water would be effective as a non-solvent in the wet spinning process of PLGA fibers. It is noted that claims 7-10 are deemed product-by-process claims due to the limitation, “produced by the process of...” and as such, determination of patentability is based on the product itself, not by the method in which it is made. If the product in the product-by-process claim is the same as or obvious from a product of the prior art, the claim is unpatentable even though the prior product was made by a different process (MPEP 2113). It is also noted that the limitation, “by interdiffusion of desorption of acetone and penetration of the water”, is considered a property specifically attributed to the particular materials being utilized. The art, as discussed above, teaches each of the particular materials claimed and, as such, would necessarily meet said limitation. A composition and its properties are inseparable. (MPEP 2112.01). Thus, the combined teachings of Stark, Nelson and Shah render the instant claims prima facie obvious. Response to Arguments Applicant's arguments, filed 2/16/2026, regarding the 103 rejection over Stark, Nelson and Shah have been fully considered but they are not persuasive. Applicant argues that Stark, Nelson and Shah do not disclose that, by using acetone as a good solvent for dissolving PDLLGA resin and using water as a poor solvent having a large deviation in Hansen solubility parameters from acetone and a higher specific gravity than acetone, acetone released from the fibrous spinning solution discharged from the nozzle outlet rises upward in the poor solvent water and therefore does not dissolve the fibers, whereby the fibers solidified by removal of acetone are deposited in a floating state in the collector vessel without adhesion between fibers and are recovered in a cotton-like form. Remarks, pages 6-9. In response, it is respectfully submitted that Applicant appears to be arguing limitations (e.g., large deviation in Hansen solubility parameters, higher specific gravity, etc.) that are not in the claims. Although the claims are interpreted in light of the specification, limitations from the specification are not read into the claims. See In re Van Geuns, 988 F.2d 1181, 26 USPQ2d 1057 (Fed. Cir. 1993). Furthermore, as explained in the rejection above, Stark teaches fibrous compositions and implant materials for bone applications and specifically describes a cotton-like material. Stark also teaches a wet spinning process. Stark teaches copolymers of glycolic and lactic acid (including D-, L-, or DL lactic acid) as well as acetone as a suitable solvent. While Stark is silent to a poor solvent (i.e., water), Nelson teaches wet-spinning PLGA/PDLLGA monofilament fibers for tissue engineering scaffolds comprising loading a dissolved polymer solution into a syringe, placing the needle tip in a coagulation bath composed of a poor solvent for the polymer, and extruding the fibers. It would have also been prima facie obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to include a poor solvent in Stark as suggested by Nelson with a reasonable expectation of success because Nelson teaches that it is conventional to place the needle tip into a coagulation bath composed of a poor solvent for the polymer when forming fibers by wet spinning. While Stark and Nelson, are silent to the particular poor solvent, water, Shah teaches that water is a known poor solvent for PLGA. 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 include the particular poor solvent, water, in Stark/Nelson as suggested by Shah with a reasonable expectation of success because Nelson teaches that a poor solvent for PLGA is known to be utilized in the wet spinning process and Shah teaches water as a known poor solvent of PLGA. A skilled artisan would have reasonably expected that any known poor solvent of PLGA such as water would be effective as a non-solvent in the wet spinning process of PLGA fibers. Thus, the combined teachings of Stark, Nelson and Shah teach the claimed invention including the elements of acetone, PDLLGA, water, etc. While the cited art does not explicitly teach a large deviation in Hansen solubility parameters between acetone and water or water having a higher specific gravity than acetone, such characteristics would necessarily result in said elements being present. Accordingly, the combined teachings of Stark, Nelson and Shah render the claimed invention prima facie obvious. Thus, for these reasons, Applicant’s arguments are found unpersuasive. Said rejection is maintained. Conclusion All claims have been rejected; no claims are allowed. 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. Correspondence Any inquiry concerning this communication or earlier communications from the examiner should be directed to CASEY HAGOPIAN whose telephone number is (571)272-6097. The examiner can normally be reached on M-F 9:00 am - 5:00 pm. 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, Sue Liu can be reached on 571-272-5539. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300. 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 https://ppair-my.uspto.gov/pair/PrivatePair. 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. Casey S. Hagopian Examiner, Art Unit 1617 /CARLOS A AZPURU/Primary Examiner, Art Unit 1617
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Prosecution Timeline

May 24, 2023
Application Filed
Dec 20, 2025
Non-Final Rejection — §103
Feb 16, 2026
Response Filed
Mar 11, 2026
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
88%
With Interview (+33.0%)
3y 5m
Median Time to Grant
Moderate
PTA Risk
Based on 558 resolved cases by this examiner. Grant probability derived from career allow rate.

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