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 .
Specification
Substitute marked-up specification filed on 12/16/2025 has been entered.
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 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 1-4 are rejected under 35 U.S.C. 103 as being unpatentable over Dehghani et al. WO2019232589 and in view of Bui et al. US9125973B2.
Regarding claims 1 and 4, Dehghani teaches medical implants derived from poly(propylene carbonate) and starch composite(page 8, lines 25-26). Dehghani notes that the poly(propylene carbonate) is synthesized by the copolymerization of CO2 and propylene oxide and that it is a biodegradable aliphatic polyester (page 2, lines 26-27). Dehghani does not address a chlorosulfonated polypropylene carbonate, however highlights that the surgical implants are prone to failure due to lack of bonding ability and high risk of infection. Dehghani notes that a person skilled in the art can generate other forms of the embodied polypropylene carbonate based composites (Industrial Applicability, page 30).
In order to improve bonding ability and decrease infection risk a skilled artisan would look to analogous art such as Bui who teaches immobilization of antimicrobial agents to polymer derived medical devices such as implants (col 1, lines 20-23 and lines 44-46). Bui discloses treating the polycarbonate surface with chlorosulfonic acid to generate sulfonyl chloride functional groups (Bui claim 7, and col 19, lines 33-35). Advantageously, Bui provides the motivation for functionalizing polycarbonate with sulfonyl chloride moieties, so that antimicrobial compounds which contain alkyl amino groups can be bonded to the polycarbonate surface (Bui, col 19, lines 23-26).
It would have been obvious to one of ordinary skilled in the art before the effective filing date of the invention to have modified Dehghani’s polypropylene carbonate to generate a chlorosulfonated polypropylene carbonate as taught by Bui for the same application of creating a medical device surface with antimicrobial activity.
The combination of Dehghani’s polypropylene carbonate and Bui’s method of reaction with a chlorosulfonic acid would be expected to generate the required chlorosulfonated polypropylene carbonate, as the same procedure is described by the instant specification. Instant specification (substitute specification: page 8, lines 3-5 and lines 13-15) notes that the required chlorosulfonated polypropylene carbonate is obtained by reacting polypropylene carbonate and a chlorosulfonation reagent such as chlorosulfonic acid.
Regarding claims 2 and 3, Dehghani discloses poly(propylene carbonate) with weight average molecular weight (Mw) of 160 KDa (page 18, line 19). Since Mw > Mn and a typical Mw/Mn ≥ 2, the number average molecular would be reasonably expected to be around 80 KDa. An obvious chlorosulfonated polypropylene carbonate derived from the combination of Dehghani and Bui would be a structure where in the required Formula I, both x and y are 0, leading to repeat unit molecular weight of 333 g/mol, which would result in degree of polymerization of 240.
Response to Arguments
Applicant's arguments filed on 12/16/2025 have been fully considered but they are not persuasive.
Applicant argues that the combination of Deghani and Bui do not teach the required chlorinated polypropylene carbonate as required by Formula I, and that the chlorine atom bound directly to the carbon atom in the polypropylene carbonate backbone would not be generated.
In response, as discussed in the rejection above, that the specification shows that the required chlorosulfonated polypropylene carbonate of Formula I is obtained by the reaction of polypropylene carbonate and a chlorosulfonation agent which can be selected to be chlorosulfonic acid (substitute specification: page 8, lines 3-5 and lines 13-15). Since the Deghani and Bui teach the same reactants as the instant specification, the same chlorosulfonation product would be expected. Applicant has not provided any reasons as to why the chlorine atom directly bonded to the carbon atom in the polypropylene carbonate backbone would not be formed even when the same reactants as recited in the specification, are also taught by Dehani and Bui.
Applicant’s arguments are therefore not convincing and the references Deghani and Bui continue to provide the support for maintaining the rejection.
Conclusion
THIS ACTION IS MADE FINAL. 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 Surbhi M Du whose telephone number is (571)272-9960. The examiner can normally be reached M-F 9:00 am to 5:00pm.
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, Heidi (Riviere) Kelley can be reached at 571-270-1831. 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.
/S.M.D./
Examiner
Art Unit 1765
/DAVID J BUTTNER/Primary Examiner, Art Unit 1765 2/17/26