Prosecution Insights
Last updated: April 19, 2026
Application No. 18/270,118

IRON OXIDE MAGNETIC PARTICLES

Non-Final OA §102§103§112§DP
Filed
Jun 28, 2023
Examiner
DICKINSON, PAUL W
Art Unit
1618
Tech Center
1600 — Biotechnology & Organic Chemistry
Assignee
ZTI BIOSCIENCES CO., LTD.
OA Round
1 (Non-Final)
63%
Grant Probability
Moderate
1-2
OA Rounds
3y 4m
To Grant
72%
With Interview

Examiner Intelligence

Grants 63% of resolved cases
63%
Career Allow Rate
646 granted / 1025 resolved
+3.0% vs TC avg
Moderate +10% lift
Without
With
+9.5%
Interview Lift
resolved cases with interview
Typical timeline
3y 4m
Avg Prosecution
43 currently pending
Career history
1068
Total Applications
across all art units

Statute-Specific Performance

§101
0.6%
-39.4% vs TC avg
§103
42.0%
+2.0% vs TC avg
§102
20.0%
-20.0% vs TC avg
§112
25.2%
-14.8% vs TC avg
Black line = Tech Center average estimate • Based on career data from 1025 resolved cases

Office Action

§102 §103 §112 §DP
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 . 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 4 and 7 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. It’s unclear what it means for the claimed iron oxide to be “derived” from complexes of iron and one or more compounds. A chemical derivative is a compound formed from a parent compound by replacing one or more atoms or functional groups with others. It’s unclear how far removed the iron oxide can be from the complexes or iron and one or more compounds and still be considered iron oxide. Further regarding claim 4, in the recitation “amine-based compound,” it’s unclear if this means compounds that comprise an amine, if this includes compounds that comprise amine derivatives, and if this includes compounds that are based on amine functionality but do not comprise an amine or amine derivative in their structure. Further regarding claim 7, it’s unclear what it means for the weight ratio to be based on iron oxide, if this means that the weight ratio being claimed is wherein iron oxide is “1” in the ratio, or if “MXn” is “1” in the ratio 1:005 to 0.10. Claim Rejections - 35 USC § 102 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 the appropriate paragraphs of 35 U.S.C. 102 that form the basis for the rejections under this section made in this Office action: A person shall be entitled to a patent unless – (a)(1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention. (a)(2) the claimed invention was described in a patent issued under section 151, or in an application for patent published or deemed published under section 122(b), in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Claims 1, 3-5, and 6-9 are rejected under 35 U.S.C. 102(a)(1) and (a)(2) as being anticipated by JP 2008-189967 A (hereafter “Fujifilm”). Fujifilm teaches magnetic nanoparticles cores comprising an iron oxide such as a-Fe2O3, y Fe2O3, FeO, or Fe3O4, and a shell of which is comprised of a platinum salt, such as PtCl4 and a polypropylene oxide coating adsorbed onto the nanoparticles; the average diameter of the nanoparticles being between 5 nm and 20 nm; and the nanoparticles being used at a frequency of 150 kHz (abstract; paragraphs 17, 31, 34-35, and 59; claims 1, 2 and 14). This is Iron oxide magnetic particles containing iron oxide and MXₙ where M is Pt (a transition metal containing electrons in a 5d orbital on the periodic table) (claim 1), wherein at least a portion of the surface of the iron oxide magnetic particles is additionally coated with a hydrophilic polymer to form a complex (claim 3), the iron oxide is derived from iron and one or more compounds selected from an amine-based compound) (claim 4); the iron oxide is a-Fe2O3, y Fe2O3, FeO, or Fe3O4 (claim 5), the polymer is polypropylene oxide (claim 6), the particles have a diameter of 0.1 nm to 1,000 nm (claim 8), and the iron oxide magnetic particles are used at a frequency of 1 kHz to 1 MHz (claim 9). 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 1-3, 5, 6, 8-11 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2008-189967 A (“Fujifilm”). The relevant portions of Fukifilm are given above. Fujifilm fails to teach “wherein the iron oxide magnetic particles contain MXn at a weight ratio of 1:0.005 to 0.08 based on iron oxide.” It would have been obvious to one of ordinary skill in the art at the time the invention was filed to optimize the amount of platinum salt on the surface of the iron oxide magnetic particles, and in this way, one would find the present weight ratio through routine experimentation with a reasonable expectation of success, as the amount of platinum salt is a result effective parameter in the use of the particles as imaging agents in MRI and X-ray contrast agents. “‘[W]here 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.’ In re Aller, 220 F.2d 454, 456, 105 USPQ 233, 235 (CCPA 1955)” MPEP § 2144.05, II. Claims 1-3, 5-11 are rejected under 35 U.S.C. 103 as being unpatentable over JP 2008-189967 A (“Fujifilm”) in further view of Kubik (Frontiers in Medicine, 2021). The relevant portions of Fujifilm are given above. Fujifilm fails to teach wherein M comprises a radioisotope. Kubik teaches that isotopic iron oxide particles are useful for tracing biological processes and the location of the particles once administered to a patient(abstract; introduction). It would have been obvious to one of ordinary skill in the art at the time the invention was made modify M to comprise a radioisotope. The motivation for this would have been to trace the path of the iron oxide nanoparticle after it enters the body to monitor when the agent reaches the portion of the body that needs imaging. 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 1-11 are provisionally rejected on the ground of nonstatutory double patenting as being unpatentable over claims 1-13 of copending U.S. Patent Application No. 18/327,118 in view of US 20140194733 to Goforth. Although the claims at issue are not identical, they are not patentably distinct from each other because the difference between the two set of claims is that the present claims recite “includes one or more selected from the group consisting of Hf, Ta, W, Re, Os, Ir, Pt, Au and Hg” where the copending recite “includes one or more from the group constitng of Tl, Pb, Bi, and Po.” However, Goforth teaches that nanoparticles coated with bismuth salts BiI3, BiCl3, and BiBr3 (corresponding to present MXₙ, wherein M is Bi; X is I, Cl, or Br; and n is 3) are useful as contrast agents. It would have been obvious to substitute the salt enumerated in the present claims with BiI3, BiCl3, and/or BiBr3, the motivation would be to produce an iron oxide magnetic particle which can be used as an x-ray contrast agent. This is a provisional nonstatutory double patenting rejection because the patentably indistinct claims have not in fact been patented. Conclusion Any inquiry concerning this communication or earlier communications from the examiner should be directed to PAUL W DICKINSON whose telephone number is (571)270-3499. The examiner can normally be reached on M-F 9 AM to 7:30 PM. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Michael Hartley can be reached on 571-272-0616. 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 http://pair-direct.uspto.gov. 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. /PAUL W DICKINSON/Primary Examiner, Art Unit 1618 December 26, 2025
Read full office action

Prosecution Timeline

Jun 28, 2023
Application Filed
Dec 27, 2025
Non-Final Rejection — §102, §103, §112 (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

1-2
Expected OA Rounds
63%
Grant Probability
72%
With Interview (+9.5%)
3y 4m
Median Time to Grant
Low
PTA Risk
Based on 1025 resolved cases by this examiner. Grant probability derived from career allow rate.

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