DETAILED ACTION
Notice of Pre-AIA or AIA Status
1. The present application, filed on or after March 16, 2013, is being examined under the first inventor to file provisions of the AIA .
Claim Status
2. Claims 1-20 are pending and examined herein.
Claim Rejections - 35 USC § 101
3. The present invention is directed to the production of Actinium-225 from Radium-225 under irradiation by neutrons produced in a nuclear fission reactor. It is known that the neutron flux in a nuclear reactor can cause the 226Ra (n, 2n) 225Ra reaction.1 Thus, the claimed invention possesses a well-established utility.
Claim Rejections - 35 USC § 112
4. The following is a quotation of the first paragraph of 35 U.S.C. 112(a):
(a) IN GENERAL.—The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor or joint inventor of carrying out the invention.
5. The following is a quotation of the first paragraph of pre-AIA 35 U.S.C. 112:
The specification shall contain a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same, and shall set forth the best mode contemplated by the inventor of carrying out his invention.
6. Claims 1-20 are rejected under 35 U.S.C. 112(a) or 35 U.S.C. 112 (pre-AIA ), first paragraph, as failing to comply with the enablement requirement. The claim(s) contains subject matter which was not described in the specification in such a way as to enable one skilled in the art to which it pertains, or with which it is most nearly connected, to make and/or use the invention. As explained above, the conversation of Ra-226 into Ra-225 by neutron irradiation in a nuclear fission reactor is a known phenomenon. Applicant’s invention differs from the prior art in that it employs a “converter material” (claim 1) comprising lithium-6 deuteride (claim 1, claim 3, claim 10). Applicant alleges that the 6LiD reacts with thermal neutrons produced in a moderated nuclear fission reactor to produce an alpha particle and a tritium nucleus, which then “undergo fusion” with one another, producing a fast neutron (see spec. at [0016]). However, there is no description in the specification to indicate how the claimed invention causes the alpha particle and tritium nucleus to “undergo fusion.”
7. Thus, the claimed invention relies on achieving nuclear fusion without meeting the accepted and established conditions necessary for fusion to occur, known as the Lawson criterion.2 “Plasmas must meet three conditions for fusion to occur, including reaching sufficient temperature, density, and [confinement] time.” Georgia State University3 explains:
“The temperatures required to overcome the coulomb barrier for fusion to occur are so high as to require extraordinary means for their achievement. Such thermally initiated reactions are commonly called thermonuclear fusion. With particle energies in the range of 1-10keV, the temperatures are in the range of 107–108 K.”
8. Lithium deuteride can be caused to undergo fusion in a nuclear weapon, using the explosive force of an uncontrolled fission reaction to compress the lithium deuteride to the extreme temperature and pressure necessary to initiate fusion between the nuclei present.4
9. However, the instant disclosure fails to describe how the conditions required for achieving fusion with the neutron capture products of the 6Li nucleus are obtained. There is no indication of how the product alpha particle and triton achieve sufficient density to encounter one another nor of how the nuclei obtain sufficient kinetic energy (temperature) to overcome the barrier to nuclear fusion.
To be enabling, the disclosure, as filed, must be sufficiently complete to enable a person of ordinary skill in the art to make and a use the full scope of the claimed invention without undue experimentation. It is the Examiner’s position that an undue amount of experimentation would be required to produce an operative embodiment of the claimed invention.
10. To determine whether a given claim is supported in sufficient detail (by combining the information provided in the disclosure with information known in the art) such that any person skilled in the art could make and use the invention as of the filing date of the application without undue experimentation, at least the following factors should be included:
(A) The breadth of the claims;
(B) The nature of the invention;
(C) The state of the prior art;
(D) The level of one of ordinary skill;
(E) The level of predictability in the art;
(F) The amount of direction provided by the inventor;
(G) The existence of working examples; and
(H) The quantity of experimentation needed to make or use the invention based on the content of the disclosure.
This standard is applied in accordance with the U.S. Federal Court of Appeals decision In re Wands, 858 F.2d at 731, 737, 8 USPQ2d 1400, 1404 (Fed. Cir. 1988). See also United States v. Telectronics Inc., 857 F.2d 778, 785, 8 USPQ2d 1217, 1223 (Fed. Cir. 1988), cert. denied, 490 U.S. 1046 (1989).
11. Reviewing the aforementioned Wands factors, the evidence weighs in favor of a finding that undue experimentation would be necessary to make and use the claimed invention, and therefore, a determination that the disclosure fails to satisfy the enablement requirement. Specifically:
(A) The breadth of the claims: Claims 1 and 11 require “a converter material.” How the converter material functions in the claimed invention is not enabled by the disclosure as filed. Federal Circuit precedent has shown that claims which are broad enough to encompass significant nonenabled subject matter will be found nonenabled: Sitrick v. Dreamworks, LLC, 516 F.3d 993, 997-1000 (Fed. Cir. 2008) (“Because the asserted claims are broad enough to cover both movies and video games, the patents must enable both embodiments”). Automotive Technologies Intern., Inc. v. BMW of North America, Inc., 501 F.3d 1274, 1285 (Fed. Cir. 2007) (“Disclosure of only mechanical side impact sensors does not permit one skilled in the art to make and use the invention as broadly as it was claimed, which includes electronic side impact sensors”). Liebel-Flarsheim Co. v. Medrad, Inc., 358 F.3d 898, 905–09 (Fed. Cir. 2004); (claim covering two types of needle holders was not enabled by description of only one of the needle holders). In re Wright, 999 F.2d 1557, 27 USPQ2d 1510 (Fed. Cir. 1993). The full scope of the claimed invention must be enabled. See MPEP § 2164.08.
(B) The nature of the invention: The nature of the invention, i.e., the subject matter to which the claimed invention pertains, revolves around the viability causing the products of neutron capture in the 6Li nucleus to undergo nuclear fusion. The disclosure fails to describe how nuclear fusion can be achieved. See MPEP § 2164.05(a).
(C) The state of the prior art: The effects claimed by Applicant have not been verified by the existing body of scientific work and are, in fact, incompatible with it. The examiner can find no literature observing nuclear fusion resultant from neutron capture in 6Li. Applicant has supplied no supporting documentation for this phenomenon. See MPEP § 2164.05(a).
(D) The level of one of ordinary skill: The “converter” of the claimed invention allegedly converts a thermal neutron into a fast neutron by a nuclear fusion reaction. Those generally skilled in the art of nuclear physics would appreciate the obstacles and repeated failure in achieving/ sustaining nuclear fusion when the Lawson criterion is not satisfied—e.g., extreme global temperature and density. See MPEP § 2164.05(b).
(E) The level of predictability in the art: There is no predictability in the art of “converting” a thermal neutron to a fast neutron by neutron capture in 6Li, as this phenomenon has not yet been reported. See MPEP § 2164.03.
(F) The amount of direction provided by the inventor: Applicant's underlying theory (spec. at [0016]) is aspirational at best, and no independent experimental results or other persuasive supporting evidence is provided for the record. See MPEP § 2164.03.
(G) The existence of working examples: There is no evidence the invention has been tested, reliably reproduced or that it enjoys mainstream support. See MPEP § 2164.02.
(H) The quantity of experimentation needed to make or use the invention based on the content of the disclosure: The quantity of experimentation needed is unreasonable because the practical guidance provided is insufficient to enable one to build or operate a working prototype of the invention, and the provided theoretical guidance is insufficient to enable one to understand the underlying sequence of phenomena required to attempt such an endeavor. See MPEP § 2164.06.
12. 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.
13. Claims 2, 4, 5, 6, 7, 16, 17, are 18 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.
14. Regarding claims 2, 4, 5, 6, 16, and 17, claim 1 is directed to a capsule with the capsule’s constituent parts being “a target material” and “a converter material.” The dependent claims are directed to physical aspects of the “capsule” but fails to specify which constituent part the dependent claims further limit. It appears that the dependent claims are attempting to describe aspects of a housing (e.g., 301 in Fig. 3) without positively claiming such a structure as a constituent element of the capsule.
15. Regarding claims 7 and 18, the term “at least partially enriched with radium-226” is unclear. The term enrichment, as it pertains to isotopes of an element, refers to increasing the amount of a particular isotope of an element to a value greater than its naturally-occurring abundance. So, “enriched uranium” refers to uranium that has greater than 0.72% of the 235U isotope, because naturally-occurring uranium comprises 0.72% 235U. Radium has no naturally-occurring isotopes, so it is impossible to enrich radium in a particular isotope. Thus, it is unclear what is meant by “a radium compound at least partially enriched with radium-226.”
Claim Rejections - 35 USC § 103
16. 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.
17. 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.
18. Claims 1-12 and 16-20 are rejected under 35 U.S.C. 103 as being unpatentable over DeGroot et al., US 2022/0108812 in view of CN-116994788-A, as evidenced by Phillips, Jr. US 33,692,888 and Tsang, US 2018/0050911.
19. Regarding claims 1, 3, and 10, DeGroot discloses a capsule (Fig. 1) configured to be inserted into a fission reactor ([0016], [0022]), the capsule comprising: a target material (5) comprising radium-226 ([0013], [0022-3]); and a converter material (3) at least partially surrounding the target material. DeGroot’s converter is “made from a material with a high thermal cross section.” DeGroot’s capsule further comprises the neutron moderator graphite (6, [0042]). CN ‘788 teaches an isotope production target comprising a moderator that could be lithium hydride (p.6), equating this material to graphite. Further, it is known that lithium deuteride is an equivalent neutron moderator or neutron absorber to lithium hydride, as evidenced by Phillips (see column 1, lines 12-15). Tsang further establishes that the 6Li isotope is a more effective thermal neutron absorber than the more abundant 7Li isotope (see Figs. 3A, 3B, 3C ). Accordingly the skilled artisan, knowledgeable in nuclear physics, at the time of the invention/filing would have found it obvious to employ a converter material comprising a compound of lithium and hydrogen at least partially enriched with lithium-6 and deuterium in the device of DeGroot to accomplish the predictable purpose of providing fast neutrons to the Ra226 target in the capsule (see DeGroot at ([0040]).
20. Regarding claim 2, the modification of DeGroot with a LiD converter material makes claim 1 obvious. DeGroot further discloses a capsule wherein the target material and the converter material are hermetically sealed within the capsule ([0042]).
21. Regarding claims 4 and 5, the modification of DeGroot with a LiD converter material makes claim 1 obvious. DeGroot further discloses a capsule wherein the capsule is a metal cylinder (7, [0042]) and wherein the target material is encapsulated within a glass vessel (4, [0042]).
22. Regarding claim 6, the modification of DeGroot with a LiD converter material makes claim 1 obvious. DeGroot further discloses a capsule further comprising at least one carbon plug arranged between the converter material and an interior side of the capsule (6, [0042]).
23. Regarding claims 7 and 9, the modification of DeGroot with a LiD converter material makes claim 1 obvious. DeGroot further discloses a capsule wherein the target material comprises a radium compound at least partially enriched with radium-226 ([0023], [0038]: because there are no naturally occurring isotopes of radium, the terminology in DeGroot indicates that its target is 100% 226Ra).
24. Regarding claim 8, the modification of DeGroot with a LiD converter material makes claim 7 obvious. DeGroot further discloses that the 226Ra “can be provided in the desired chemical form ( as a metal oxide, salt, or mixture thereof) ([0038]). Accordingly, one of ordinary skill in the art at the time of invention/filing would have found the specific radium chloride salt to be obvious based on DeGroot’s disclosure of the generic radium salt as a suitable target compound.
25. Regarding claim 10, DeGroot further disclose a method of obtaining actinium-225 (see claim 1), the method comprising: inserting a capsule (Fig. 1) comprising a target material (5) comprising radium-226 ([0022]) and a converter material (3) at least partially surrounding the target material into a fission reactor (step (a)(i)),leaving the capsule in the fission reactor for a first time period (steps (a)(i) and (b));removing the capsule from the fission reactor (implicit) ;extracting the target material from the capsule (implicit); and milking the target material for actinium (step (c)).
DeGroot’s converter is “made from a material with a high thermal cross section.” DeGroot’s capsule further comprises the neutron moderator graphite (6, [0042]). CN ‘788 teaches an isotope production target comprising a moderator that could be lithium hydride (p.6), equating this material to graphite. Further, it is known that lithium deuteride is an equivalent neutron moderator or neutron absorber to lithium hydride, as evidenced by Phillips (see column 1, lines 12-15). Tsang further establishes that the 6Li isotope is a more effective thermal neutron absorber than the more abundant 7Li isotope (see Figs. 3A, 3B, 3C ). Accordingly the skilled artisan, knowledgeable in nuclear physics, at the time of the invention/filing would have found it obvious to employ a converter material comprising a compound of lithium and hydrogen at least partially enriched with lithium-6 and deuterium in the device of DeGroot to accomplish the predictable purpose of providing fast neutrons to the Ra226 target in the capsule (see DeGroot at ([0040]).
26. Regarding claim 11, the modification of DeGroot with a LiD converter material makes claim 11 obvious. DeGroot further disclose a method wherein the first time period is at least 5 days 9see Fig. 2).
27. Regarding claim 16, the modification of DeGroot with a LiD converter material makes claim 11 obvious. DeGroot further discloses a capsule wherein the target material and the converter material are hermetically sealed within the capsule ([0042]).
28. Regarding claim 17, the modification of DeGroot with a LiD converter material makes claim 11 obvious. DeGroot further discloses a capsule wherein the capsule is a metal cylinder (7, [0042])
29. Regarding claims 18 and 20, the modification of DeGroot with a LiD converter material makes claim 11 obvious. DeGroot further discloses a capsule wherein the target material comprises a radium compound at least partially enriched with radium-226 ([0023], [0038]: because there are no naturally occurring isotopes of radium, the terminology in DeGroot indicates that its target is 100% 226Ra).
27. Regarding claim 19, the modification of DeGroot with a LiD converter material makes claim 11 obvious. DeGroot further discloses that the 226Ra “can be provided in the desired chemical form ( as a metal oxide, salt, or mixture thereof) ([0038]). Accordingly, one of ordinary skill in the art at the time of invention/filing would have found the specific radium chloride salt to be obvious based on DeGroot’s disclosure of the generic radium salt as a suitable target compound.
28. Claims 13 and 14 are rejected under 35 U.S.C. 103 as being unpatentable over DeGroot et al., US 2022/0108812 as applied to claim 11 and further in view of Bernstein et al., US 2022/0199276.
29. Regarding claims 13 and 14, the modification of DeGroot with a LiD converter material makes claims 11 and 12 obvious. Bernstein teaches a method of isolating Ac225 from a fast neutron irradiated Ra226 target material (Abs., [0024-5])) comprising further comprising waiting for at least 1 hour between extracting the target material from the capsule and milking the target material for actinium and wherein milking the target material for actinium comprises: a first milking period during which the target material is milked for actinium, thereby producing a first yield of actinium that includes actinium-225 and actinium-227; and a second milking period during which the target material is milked for actinium, thereby producing a second yield of actinium that consists essentially of actinium-225 ([0038-9]). One of ordinary skill in the art at the time of invention/filing would have found it obvious to employ the Ac225 isolation steps taught by Bernstein to the method of DeGroot for the predictable purpose of “producing actinium-225 that is free of contamination from both fission fragments and actinium-227…with a radiochemical purity of 99.9999% ([0022]).
30. Claim 15 is rejected under 35 U.S.C. 103 as being unpatentable over DeGroot et al., US 2022/0108812 as applied to claim 11 and further in view of Allen et al., US 2013/0336436.
31. Regarding claim 15, the modification of DeGroot with a LiD converter material makes claim 11 obvious. DeGroot is silent a as to how the capsule is inserted into the reactor. Allen teaches a method of producing radioisotopes ([0003]) by irradiation of a capsule in a nuclear reactor ([0031]), the method comprising operating a drive unit to drive the capsule through a guide tube into the fission reactor (see Fig. 2, Fig. 8; [0037-8])). One of ordinary skill in the art at the time of invention/filing would have found it obvious to apply the capsule insertion methodology taught by Allen to the method of DeGroot for the predictable purpose of producing radioisotopes in a commercial nuclear reactor “without shutting down the reactor or requiring chemical extraction processes.”
Conclusion
Any inquiry concerning this communication or earlier communications from the examiner should be directed to SHARON M DAVIS whose telephone number is (571)272-6882. The examiner can normally be reached Monday - Thursday, 7:00 - 5:00 pm ET.
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/SHARON M DAVIS/Primary Examiner, Art Unit 3646
1 See Iwahashi and Melville attached hereto.
2 The Science of Fusion Where triple product reigns supreme”, https://usfusionenergy.org/science-fusion (last visited 03/18/26).
3 Temperatures for Fusion, Department of Physics and Astronomy, Georgia State University: <http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/coubar.html>.
4 Cochran, Thomas B., Norris, Robert S.. "nuclear weapon". Encyclopedia Britannica, 13 Jun. 2026, https://www.britannica.com/technology/nuclear-weapon. Accessed 23 June 2026. Attached hereto.
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