DETAILED ACTION
Claims 1-44 are pending and claims 1-2, 4-5, 11-18, 28-29, and 34-43 are currently under review.
Claims 3, 6-10, 19-27, 30-33, and 44 are withdrawn.
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/Remarks
The remarks filed 9/18/2026 have been entered. Applicant’s remarks have overcome each and every 112(b) rejection previously set forth in the Non-Final Office Action mailed 5/18/2026.
Claim Interpretation
The term “precious metal” is interpreted to refer to any metal that is not a “base metal”, and the term “base metal” is interpreted to refer to any metal that is not a “precious metal” as defined in [0153-0154] of the instantly filed specification.
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.
Claim(s) 1-2, 4-5, 11-14, 34, and 36-41 is/are rejected under 35 U.S.C. 102(a)(1) as being anticipated by Little (US 4,645,535).
Regarding claims 1-2 and 4-5, Little discloses a method for recovery (ie. liberating) of precious metals such as gold, silver, platinum etc. from a sulfide ore (ie. sulfide encapsulating the precious metal), wherein said method includes a step of contacting the ore material with a thiourea such as thiosemicarbazide under acidic conditions in a lixiviant solution [abstract, col.3 ln.13-45].
Regarding claims 11-14, Little discloses the method of claim 1 (see previous). Little further teaches a concentration of 2 g of said thiourea (which can be thiosemibarbazide as stated above) in 907 g of water, which results in approximately 2.2 g/L of said thiourea and converts to a molarity of approximately 24 mM of thiourea based on a molar mass of 91.13 g/mol of thiosemicarbazide as calculated by the examiner [col.3 ln.34-37]. Specifically regarding claim 14, the term “about” allows for deviation of 20% of the modified term (in this case “20 mM”) and therefore allows for up to 24 mM, which meets the claimed range.
Regarding claims 34 and 36, Little discloses the method of claim 1 (see previous). The examiner notes that the lixiviant solution formation step of Little (ie. contacting) naturally results in separation of remaining precious metals from the ore and therefore meets the limitation of “residue” according to broadest reasonable interpretation. The examiner also notes that contact between the precious metal residue in the lixiviant solution meets the limitation of “contacting with a lixiviant” as claimed.
Regarding claims 37-38, Little discloses the method of claim 1 (see previous). The examiner notes that the lixiviation of Little reasonable meets the limitation of leaching [col.1 ln.28-30], wherein the lixiviant solution of Little would naturally be stored in some kind of container which meets the limitation of tank/vat leaching.
Regarding claims 39-41, Little discloses the method of claim 1 (see previous). Little further teaches cementation recovery of the precious metals [col.3 ln.46-52]. The examiner notes that cementation of the precious metals from the solution naturally meets the limitation of solid-liquid separation.
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) 11-18, 37-38, and 43 is/are rejected under 35 U.S.C. 103 as being unpatentable over Little (US 4,645,535) in view of Dixon et al. (WO2016165027).
Regarding claims 11-18, Little discloses the method of claim 1 (see previous). Little does not expressly teach reagent concentration ranges as claimed. Dixon et al. discloses that it is known to recover precious metals from base metal sulfide materials [abstract, p.2]; wherein the base metal can first be extracted from said base metal materials by contacting with a thiourea reagent concentration of less than 0.3 mM or about 0.2 mM [p.17]. The examiner notes that the range of “less than 0.3 mM” overlaps with the claimed ranges. Alternatively, the examiner notes that the term “about” allows for values below 0.2 mM, which overlaps with or is substantially close to the claimed range of “about 0.002 to 0.02 mM” of claim 18 because similar results of recovering precious metals are achieved. Alternatively, Dixon et al. further teaches embodiments such as example 1 wherein 0 to 10 mM of reagent is utilized, which overlaps with all of the claimed ranges [p.18]. See MPEP 2144.05(I). Therefore, it would have been obvious to one of ordinary skill to modify the method of Little by including an initial thiourea extraction step to extract base metal materials such as Cu and/or Ni as taught by Dixon et al.
Regarding claims 37-38, Little discloses the method of claim 1 (see previous). Dixon et al. teaches an initial extraction/leaching step as explained above, wherein said leach can further be several types of leaching to such as percolation leaching or heap leaching [p.15].
Regarding claim 43, the aforementioned prior art discloses the method of claim 1 (see previous). As stated above, Dixon et al. discloses that it is known to recover precious metals from base metal sulfide materials of Cu and/or Ni (see previous).
Claim(s) 28-29 and 35 is/are rejected under 35 U.S.C. 103 as being unpatentable over Little (US 4,645,535) in view of either one of Riekkola-Vanhanen et al. (US 2008/0241024) or Li et al. (CN103789546, machine translation referred to herein).
Regarding claims 29 and 35, the aforementioned prior art discloses the method of claim 1 (see previous). The aforementioned prior art does not expressly teach pressure oxidation with oxygen during contacting/leaching as claimed. However, this feature would have been obvious in view of the prior art. Riekkola-Vanhanen et al. discloses that controlled oxygen pressure and addition of sulfites are both known means of controlling leaching [0025]. Li et al. also teaches metal recovery with thioureas wherein oxidation treatment can be performed by oxygen pressure oxidation or chemical oxidation [0034, 0037-0038]. Therefore, it would have been obvious to one of ordinary skill to utilizing an oxidizing agent such as oxygen to control leaching as taught by the prior art above.
Claim(s) 41-42 is/are rejected under 35 U.S.C. 103 as being unpatentable over Little (US 4,645,535) in view of Dixon et al. (WO2018072029, herein referred to as “Dixon et al. (‘029)”).
Regarding claim 42, the aforementioned prior art discloses the method of claim 1 (see previous). The aforementioned prior art does not expressly teach a step of recovering the reagent as claimed. Dixon et al. (‘029) teaches recirculation (ie. recovery) of the thiocarbonyl reagent to the lixiviant such that extraction may be supplemented [p.11]. Therefore, it would have been obvious to one of ordinary skill to modify the method of the aforementioned prior art by recovering the reagent as taught by Dixon et al. (‘029) to supplement lixiviation.
Claim(s) 43 is/are rejected under 35 U.S.C. 103 as being unpatentable over Little (US 4,645,5359) in view of Lesoille (US 4,342,591).
Regarding claim 43, Little discloses the method of claim 1 (see previous). Little does not expressly teach that the precious metal is encapsulated by a base metal sulfide as claimed. Lesoille discloses that it is well known that precious metals are contained (ie. encapsulated) in base metal sulfides, wherein thiourea treatment is a known way of industrially and economically recovering precious metals from said sulfides [abstract, col.1 ln.55-64]. Therefore, it would have been obvious to one of ordinary skill to modify the method of Little by recovering precious metals from base metal sulfides as an economic and industrial way to recover precious metals from ores.
Response to Arguments
The previous 102 and 103 rejections over Dixon et al. are withdrawn in view of applicant’s remarks. However, upon further consideration, a new ground(s) of rejection is made in view of Little as explained above.
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to NICHOLAS A WANG whose telephone number is (408)918-7576. The examiner can normally be reached usually M-Th: 7-5.
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, Jonathan Johnson can be reached at 5712721177. The fax phone number for the organization where this application or proceeding is assigned is 571-273-8300.
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/NICHOLAS A WANG/Primary Examiner, Art Unit 1734
