DETAILED ACTION 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. Election/Restrictions Applicant’s election without traverse of claim 11 in the reply filed on 11/14/25 is acknowledged. New claims 31-39 depend upon elected claim 11. 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. Claim s 31-33 and 35-36 are rejected under 35 U.S.C. 112(b) as being indefinite for failing to particularly point out and distinctly claim the subject matter which the inventor or a joint inventor, or for pre-AIA the applicant regards as the invention. Claims 31-33 recite a % of rare earth metals in the rare earth oxide powder. It is unclear if the % refers to mol, weight, volume, or some other measure of percentage, such as a metals basis. Claim 35 recite s a % of base metals in the rare earth oxide powder. It is unclear if the % refers to mol, weight, volume, or some other measure of percentage, such as a metals basis. Claim 36 recite s a % of rare earth metals solubilized from the rare earth oxide powder. It is unclear if the % refers to mol, weight, volume, or some other measure of percentage, such as a metals basis. 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 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. Language from the reference(s) is shown in quotations. Limitations from the claims are shown in quotations within parentheses. Examiner explanations are shown in italics. 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. 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 set forth in Graham v. John Deere Co. , 383 U.S. 1, 148 USPQ 459 (1966), that are applied 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. Claim s 11 and 36 are rejected under 35 U.S.C. 103 as being unpatentable over Brewer et al. ( WO 2014066668 A1). Regarding claim 1 1 , Brewer teaches that “methods are described for the recovery and separation of the rare earth elements from ore, tailings, or any other solid source” (which reads upon “a method for the selective separation of rare earth elements, comprising the steps of”, as recited in the instant claim; abstract). Brewer teaches “the extraction and separation of REE oxides, hydroxides, salts and organometallic compounds through the use of mechanochemistry” (which reads upon “digesting a rare earth oxide powder”, as recited in the instant claim; page 2). Brewer teaches that “ i n the case of the method titration is used by adding a solution stepwise which contains a precipitating compound such as sodium hydroxide, or oxalic acid to a solution containing REE compound , and that a variety of other acids may be used including nitric acid , hydrochloric acid, sulfuric acid, trichloroacetic acid, phosphoric acid, formic acid, acetic acid, propionic acid, carbonic acid mixtures of these or other suitable acids ” (which reads upon “ in nitric acid to form a first rare earth solution comprising solubilized rare earth elements ”, as recited in the instant claim; page 5 ). Brewer teaches that “ the base may be selected from sodium hydroxide, potassium hydroxide, magnesium hydroxide, calcium hydroxide, sodium bicarbonate, calcium carbonate, ammonium hydroxide , potassium carbonate, lithium hydroxide, mixtures of these, or other suitable bases ” (which reads upon “ contacting the first rare earth solution with ammonium hydroxide ”, as recited in the instant claim; page 5 ). Brewer teaches that “the addition of a precipitating agent to the REE containing solution causes the REE to come out of solution as a solid which is no longer soluble in the original solvent ” (which reads upon “ to precipitate a first precipitation product and form a second rare earth solution ”, as recited in the instant claim; page 5 ). Brewer teaches that “the pH 1 adjusted solution was then titrated with a base (i.e., NaOH or KOH) to various pH end points ” ( page 8 ). Brewer teaches that “ a t those end points, specific materials precipitated and the solution was centrifuged to separate the precipitated solid material from the solution ” (which reads upon “ separating the first precipitation product from the second rare earth solution ”, as recited in the instant claim; page 8 ). Brewer teaches that “ a t each endpoint, the solution was decanted from the solid precipitate and titrated to the next end point ” (which reads upon “ increasing the pH of the second rare earth solution to precipitate additional rare earth elements from the second rare earth solution as a first intermediate particulate feed ”, as recited in the instant claim; page 8 ). Brewer teaches that “ a s the pH of the solution increased each REE element precipitated selectively and was collected for further verification of the purity and identity of the REE present ” (which reads upon “ increasing the pH of the second rare earth solution to precipitate additional rare earth elements from the second rare earth solution as a first intermediate particulate feed ”, as recited in the instant claim; page 9 ). Brewer is silent regarding digesting the first intermediate particulate feed in nitric acid to form a third rare earth solution; and contacting the third rare earth solution with ammonium hydroxide to precipitate a second precipitation product and form a fourth rare earth solution , which amounts to a repetition of the process performed . Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to modify the process of Brewer to include digesting the first intermediate particulate feed in nitric acid to form a third rare earth solution; and contacting the third rare earth solution with ammonium hydroxide to precipitate a second precipitation product and form a fourth rare earth solution so that the REE product recovered will become purer and more impurities can be removed . Mere duplication of known elements has no patentable significance unless a new and unexpected result is produced. In re Harza, 124 USPQ 378, 380 (CCPA 1960). Regarding claim 36 , modified Brewer teaches the method of claim 11 as stated above. Brewer teaches that “the process has been shown to extract > 90% of the REE from both simulate and actual ore samples” (page 7; REE must be solubilized to be recovered ). Brewer teaches “ nearly 100% recovery of the REE compounds ” (page 5 ). Claim s 31-33 and 35 are rejected under 35 U.S.C. 103 as being unpatentable over Brewer et al. ( WO 2014066668 A1 ), as applied to claim 1 1 above, and further in view of Li et al. ( CN 1098361 C ) , as machine translated . Regarding claim s 31-33 and 35 , Brewer teaches the method of claim 1 1 as stated above. Brewer is silent regarding the starting composition of the rare earth oxide powder. Brewer teaches that “methods are described for the recovery and separation of the rare earth elements from ore, tailings, or any other solid source” (abstract). Li is similarly concerned with rare earth oxides (paragraph [00 06 ]). Li teaches “ a process for extracting and separating cerium and thorium from bastnaesite leachat e ” (paragraph [00 04 ]). Li teaches that “the back-extraction solution containing cerium organic phase was treated as in Example 1 to obtain cerium oxide ” (which reads upon “ rare earth oxide powder ”, as recited in the instant claim; paragraph [00 23 ]). Li teaches that “the CeO<sub>2</sub> extraction recovery rate was 91%, and the CeO<sub>2</sub>/REO ratio was 99.99% ” (which reads upon “ wherein the rare earth oxide powder comprises at least about 90, 95, or 97% rare earth metals ”, as recited in instant claim s 31-33 ; which reads upon “wherein the rare earth oxide powder comprises not greater than about 0.02% base metals”, as recited in instant claim 35 ; paragraph [00 23 ]). Li teaches that “the contents of rare earth impurities were as follows: 0.002% La, 0.0006% Pr, 0.0014% Nd, Sm < 0.0005%, Eu < 0.0005%, Gd < 0.0005%, Tb < 0.0005%, Dy < 0.0005%, Ho < 0.0005%, Er < 0.0005%, Tm < 0.0005%, Yb < 0.0005%, Lu < 0.0005%, Y < 0.0005% ” (paragraph [00 23 ]). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use the CeO powder of Li in the method of Brewer because Brewer teaches that any solid source may be used. Claim 34 is rejected under 35 U.S.C. 103 as being unpatentable over Brewer et al. (WO 2014066668 A1), as applied to claim 11 above, and further in view of Calkins et al. (US 2815264 A ). Regarding claim 34 , Brewer teaches the method of claim 11 as stated above. Brewer is silent regarding wherein the metal impurities in the rare earth oxide powder comprise thorium and uranium . Brewer teaches that “methods are described for the recovery and separation of the rare earth elements from ore, tailings, or any other solid source” (abstract). Calkins is similarly concerned with a process for the recovery of thorium, uranium, and rare earths from their ores , particularly monazite sand ( column 1 , lines 15-17 ). Calkins teaches that “the most important source of thorium and the rare earths is monazite sand” (column 1 , lines 18-20 ). Calkins teaches that “the rare earth oxide content may run as high as 86%, the thorium oxide content as high as 10%, and the uranium oxide (U 3 O 8 ) as high as 1%” (which reads upon “wherein the metal impurities in the rare earth oxide powder comprise thorium and uranium”, as recited in the instant claim; column 1 , lines 18-30 ). Accordingly, it would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to use monazite sand in the method of Brewer, as taught by Calkins because the most important source of thorium and the rare earths is monazite sand and because Brewer teaches that any solid source can be used. The selection of a known material, which is based upon its suitability for the intended use, is within the ambit of one of ordinary skill in the art. See In re Leshin, 125 USPQ 416 (CCPA 1960), Sinclair & Carroll Co. v. Interchemical Corp., 325 U.S. 327, 65 USPQ 297 (1945), and MPEP § 2144.07. Here Calkins teaches that monazite sand is a known material suitable as a source of rare earth metals for an extraction process. Claim s 37-39 are rejected under 35 U.S.C. 103 as being unpatentable over Brewer et al. (WO 2014066668 A1), as applied to claim 11 above, and further in view of Chiola et al. (US 3582264 A). Regarding claim s 37-39 , Brewer teaches the method of claim 11 as stated above. Brewer teaches that “the pH 1 adjusted solution was then titrated with a base (i.e., NaOH or KOH) to various pH end points” (page 8). Brewer is silent regarding the exact pH end points used and the %HNO3 . Regarding the subject limitations, in order to carry out the invention of Brewer , it would have been necessary and obvious to look to the prior art for exemplary pH end points used and the %HNO3 used in rare earth extraction processes. Chiola provides this teaching. Chiola is similarly concerned with the process for separating the lighter rare earth elements from heavier rare earth elements (abstract). Chiola teaches “an improvement to a process for separating and purifying rare earth material wherein a first extraction step is used to separate the light and heavy rare earths and thereafter the phase containing the heavier rare earths is further processed to separate the particular rare earth desired from the other heavier rare earths” (column 2, lines 50-64). Chiola teaches “scrubbing the organic extraction phase that is loaded with the heavier rare earths with an aqueous acidic scrub solution, adjusting the pH of the aqueous acidic solution after scrubbing to between about 5 and 7 and adding the adjusted solution to the extraction step at an intermediate stage to thereby increase the efficiency of the extraction step” (column 2, lines 50-64). Chiola teaches that “the pH of the scrub solution, after scrubbing, is below about 3” (column 3, lines 34-48). Chiola teaches that “it is adjusted to a pH of about 5 to about 7 by the addition of a base” (which reads upon “wherein the step of contacting the first rare earth solution with ammonium hydroxide results in a pH of at least about pH 4”, as recited in instant claim 38; which reads upon “wherein the step of contacting the first rare earth solution with ammonium hydroxide results in a pH of not greater than about pH 5.5”, as recited in instant claim 39; column 3, lines 34-48). Chiola teaches that “aqueous ammonium hydroxide solutions containing from about 5% to about 20% by weight of ammonium hydroxide are especially preferred” (which reads upon “at least about 18% HNO3”, as recited in instant claim 37; column 3, lines 34-48). It would have been obvious to one of ordinary skill in the art before the effective filing date of the claimed invention to perform the method of Brewer , adjusting and varying the pH and %HNO3 , such as within the claimed ranges, as taught by Chiola , motivated to perform a conventional rare earth extraction process using known and tested pH end points used and %HNO3 . Contact Information Any inquiry concerning this communication or earlier communications from the examiner should be directed to REBECCA JANSSEN whose telephone number is (571)272-5434 . The examiner can normally be reached on Mon-Thurs 10-7 and alternating Fri 10-6 . 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. The Examiner requests that interviews not be scheduled during the last week of each fiscal quarter or the last half of September, which is the end of the fiscal year. Q1: 1/5-1/9/26; Q2: 3/30-4/3/26; Q3: 6/22-6/26/26; Q4: 9/21-9/30/26. If attempts to reach the examiner by telephone are unsuccessful, the examiner’s supervisor, Keith Hendricks can be reached on (571)272-1401 . 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. /REBECCA JANSSEN/ Primary Examiner, Art Unit 1733