Prosecution Insights
Last updated: September 17, 2026
Application No. 18/850,486

LITHIUM HYDRIDE FIRST WALL

Non-Final OA §112
Filed
Sep 24, 2024
Priority
Apr 04, 2022 — EU 22305451.1 +1 more
Examiner
DAVIS, SHARON M
Art Unit
Tech Center
Assignee
Renaissance Fusion
OA Round
1 (Non-Final)
68%
Grant Probability
Favorable
1-2
OA Rounds
1y 6m
Est. Remaining
95%
With Interview

Examiner Intelligence

Grants 68% — above average
68%
Career Allowance Rate
421 granted / 619 resolved
+8.0% vs TC avg
Strong +27% interview lift
Without
With
+26.7%
Interview Lift
resolved cases with interview
Typical timeline
3y 6m
Avg Prosecution
44 currently pending
Career history
668
Total Applications
across all art units

Statute-Specific Performance

§101
6.6%
-33.4% vs TC avg
§103
44.8%
+4.8% vs TC avg
§102
7.0%
-33.0% vs TC avg
§112
37.8%
-2.2% vs TC avg
Black line = Tech Center average estimate • Based on career data from 619 resolved cases

Office Action

§112
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 Status 1. Claims 1-19 are pending and examined herein. Drawings 2. The drawings are objected to under 37 CFR 1.83(a). The drawings must show every feature of the invention specified in the claims. Therefore, the features of claims 11 and 15 must be shown or the feature(s) canceled from the claim(s). No new matter should be entered. Corrected drawing sheets in compliance with 37 CFR 1.121(d) are required in reply to the Office action to avoid abandonment of the application. Any amended replacement drawing sheet should include all of the figures appearing on the immediate prior version of the sheet, even if only one figure is being amended. The figure or figure number of an amended drawing should not be labeled as “amended.” If a drawing figure is to be canceled, the appropriate figure must be removed from the replacement sheet, and where necessary, the remaining figures must be renumbered and appropriate changes made to the brief description of the several views of the drawings for consistency. Additional replacement sheets may be necessary to show the renumbering of the remaining figures. Each drawing sheet submitted after the filing date of an application must be labeled in the top margin as either “Replacement Sheet” or “New Sheet” pursuant to 37 CFR 1.121(d). If the changes are not accepted by the examiner, the applicant will be notified and informed of any required corrective action in the next Office action. The objection to the drawings will not be held in abeyance. Claim Objections 2. Claims 3, 7, 18, and 19 objected to because of the following listed informalities. Appropriate correction is required. In claim 3, the word “have” should be “has.” In claim 7, the phrases “the width of the first wall is…comprised between” should be amended to “a width of the first wall is between.” (There are two instances needing correction in the claim.) In claim 18, the preamble should be amended to “A method adapted to form the first wall according to claim 1, the method comprising: In claim 19, the word “applicating” should be amended to “applying.” (There are two instances needing correction in the claim.) Claim Interpretation The following is a quotation of 35 U.S.C. 112(f): (f) Element in Claim for a Combination. – An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. The following is a quotation of pre-AIA 35 U.S.C. 112, sixth paragraph: An element in a claim for a combination may be expressed as a means or step for performing a specified function without the recital of structure, material, or acts in support thereof, and such claim shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof. 3. The claims in this application are given their broadest reasonable interpretation using the plain meaning of the claim language in light of the specification as it would be understood by one of ordinary skill in the art. The broadest reasonable interpretation of a claim element (also commonly referred to as a claim limitation) is limited by the description in the specification when 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is invoked. As explained in MPEP § 2181, subsection I, claim limitations that meet the following three-prong test will be interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph: (A) the claim limitation uses the term “means” or “step” or a term used as a substitute for “means” that is a generic placeholder (also called a nonce term or a non-structural term having no specific structural meaning) for performing the claimed function; (B) the term “means” or “step” or the generic placeholder is modified by functional language, typically, but not always linked by the transition word “for” (e.g., “means for”) or another linking word or phrase, such as “configured to” or “so that”; and (C) the term “means” or “step” or the generic placeholder is not modified by sufficient structure, material, or acts for performing the claimed function. Use of the word “means” (or “step”) in a claim with functional language creates a rebuttable presumption that the claim limitation is to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites sufficient structure, material, or acts to entirely perform the recited function. Absence of the word “means” (or “step”) in a claim creates a rebuttable presumption that the claim limitation is not to be treated in accordance with 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. The presumption that the claim limitation is not interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, is rebutted when the claim limitation recites function without reciting sufficient structure, material or acts to entirely perform the recited function. Claim limitations in this application that use the word “means” (or “step”) are being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. Conversely, claim limitations in this application that do not use the word “means” (or “step”) are not being interpreted under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph, except as otherwise indicated in an Office action. 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. 4. Claims 4, 5, 7, and 10-19 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. 5. Regarding claim 4, the phrase "for example" renders the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d). 6. Regarding claim 5, the phrases “for example” and “preferably” render the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d). Further, the recitation “of high atomic number” is relative and indefinite. Finally, the recitation “lithium” in the last line is unclear because claim 1 introduces a “liquid metal mixture comprising at lease lithium and lithium hydride. It appears this limitation should be amended to “…interaction between the liquid metal mixture and the core.” The examiner suggests the following language: at least one of the pebbles is a neutron attenuating pebble having a core primarily comprising lead; and/or at least one of the pebbles is a neutron multiplying pebble having a core primarily comprising beryllium; and/or the outer shell primarily comprises silicon carbide or graphite. 7. Regarding claim 7, the phrase "for example" renders the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d). 8. Regarding claim 10 (and dependents), the scope of the claim is unclear because the preamble is redundant. What is the different between “a first wall device” and “a first wall”? Further, the recitation “a liquid metal mixture…” is unclear because claim 1 already introduces this recitation. The examiner suggests amending claim 10 as follows: The vessel according to claim 10, further comprising flowing means adapted to form a flow of the liquid metal mixture on the inner wall. 10. Regarding claim 11, claim limitation “means for adding the pebbles” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. However, the written description fails to disclose the corresponding structure, material, or acts for performing the entire claimed function and to clearly link the structure, material, or acts to the function. The disclosure fails to describe the structure associated with the means for adding the pebbles and there is no depiction of the structure in the drawings. Therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Applicant may: (a) Amend the claim so that the claim limitation will no longer be interpreted as a limitation under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph; (b) Amend the written description of the specification such that it expressly recites what structure, material, or acts perform the entire claimed function, without introducing any new matter (35 U.S.C. 132(a)); or (c) Amend the written description of the specification such that it clearly links the structure, material, or acts disclosed therein to the function recited in the claim, without introducing any new matter (35 U.S.C. 132(a)). If applicant is of the opinion that the written description of the specification already implicitly or inherently discloses the corresponding structure, material, or acts and clearly links them to the function so that one of ordinary skill in the art would recognize what structure, material, or acts perform the claimed function, applicant should clarify the record by either: (a) Amending the written description of the specification such that it expressly recites the corresponding structure, material, or acts for performing the claimed function and clearly links or associates the structure, material, or acts to the claimed function, without introducing any new matter (35 U.S.C. 132(a)); or (b) Stating on the record what the corresponding structure, material, or acts, which are implicitly or inherently set forth in the written description of the specification, perform the claimed function. For more information, see 37 CFR 1.75(d) and MPEP §§ 608.01(o) and 2181. 11. Regarding claim 12, the phrase "for example" renders the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d). Further, the recitation “divided in at least two parts in the vessel” is unclear. At a minimum, the first tube is illustrated as being exterior to the vessel (see Fig. 1), so the recitation is not consistent with the disclosure (see MPEP 2173.03). 12. Regarding claim 13, the recitation “adapted to circulating the…” is indefinite because it does not adequately delineate what structure the flowing means must possess to make it capable of the recited function. See MPEP 2111.04 and 2173.05(g). Further , the phrase "for example" renders the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d). 13. Regarding claim 16, claim limitation “means for generating a magnetic field” invokes 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph. However, the written description fails to disclose the corresponding structure, material, or acts for performing the entire claimed function and to clearly link the structure, material, or acts to the function. The disclosure fails to describe the structure associated with the means for adding the pebbles and there is no depiction of the structure in the drawings. Therefore, the claim is indefinite and is rejected under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. Applicant may: (a) Amend the claim so that the claim limitation will no longer be interpreted as a limitation under 35 U.S.C. 112(f) or pre-AIA 35 U.S.C. 112, sixth paragraph; (b) Amend the written description of the specification such that it expressly recites what structure, material, or acts perform the entire claimed function, without introducing any new matter (35 U.S.C. 132(a)); or (c) Amend the written description of the specification such that it clearly links the structure, material, or acts disclosed therein to the function recited in the claim, without introducing any new matter (35 U.S.C. 132(a)). If applicant is of the opinion that the written description of the specification already implicitly or inherently discloses the corresponding structure, material, or acts and clearly links them to the function so that one of ordinary skill in the art would recognize what structure, material, or acts perform the claimed function, applicant should clarify the record by either: (a) Amending the written description of the specification such that it expressly recites the corresponding structure, material, or acts for performing the claimed function and clearly links or associates the structure, material, or acts to the claimed function, without introducing any new matter (35 U.S.C. 132(a)); or (b) Stating on the record what the corresponding structure, material, or acts, which are implicitly or inherently set forth in the written description of the specification, perform the claimed function. For more information, see 37 CFR 1.75(d) and MPEP §§ 608.01(o) and 2181. 14. Regarding claim 17, the recitation “forms at least part of a plasma confinement vessel, a nuclear reactor vessel, or an isotopic separation chamber” is unclear because this recitation does not clearly delineate what additional structure the vessel of claim 10 possesses to meet the limitation of claim 17. Rather, the limitation seems to denote an intended use of the vessel. Further, the term “first wall” introduced in claim 1 has a specific meaning in the art of plasma confinement (see the instant specification at [0002]) and it is unclear how such a structure would be useful in a nuclear reactor vessel (e.g.., a boiling or pressurized water reactor vessel, which does not utilize plasma) or in an isotopic separation chamber, which has no particular definition. 15. Regarding claim 18, the recitation “a liquid metal mixture” is unclear because claim 1 already introduces this term. Claim 18 should be amended as follows: A method adapted to form the first wall according to claim 1, the method comprising: injecting the liquid metal mixture to an inner wall of a vessel. 16. Regarding claim 19, the phrases "for example" and “such as” render the claim indefinite because it is unclear whether the limitation(s) following the phrase are part of the claimed invention. See MPEP § 2173.05(d). Allowable Subject Matter 17. Claim 1 is allowed. 18. The following is a statement of reasons for the indication of allowable subject matter: Woolley (cited on attached PTO892) is considered the closest prior art. Wooley’s first wall is made of lithium and has neither lithium hydride nor pebbles. ITO (cited on the attached PTO-892) teaches a liquid lithium first wall composition comprising solid particles of lithium compounds are included in the liquid lithium. Davis (cited on attached PTO-892) teaches a first wall comprising a lithium alloy material with suspended pellets of metal hydride (Fig. 4 and [0046-7]), but does not specifically teach lithium hydride. It is noted that the Pereira cited on the IDS dated 09/24/24 does not provide reasonable motivation to modify a liquid lithium first wall material with lithium hydride because it is directed to the use of lithium hydride in a solid lithium material for improving mechanical properties. Further, pellets for first walls are known (e.g., Plaza cited on the attached PTO-892), but there is no teaching, suggestion, or motivation to combine them with a liquid lithium first wall. 19. Although many of the structural limitations of the independent claims may be found separately in the prior art, it would not have been obvious to one of ordinary skill in the art at the time of filing to combine the separately taught limitations to arrive at the claimed invention without the hindsight of utilizing the present disclosure as a blueprint. 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. 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, Jack Keith can be reached at 571-272-6878. 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. /SHARON M DAVIS/Primary Examiner, Art Unit 3646
Read full office action

Prosecution Timeline

Sep 24, 2024
Application Filed
Aug 13, 2026
Non-Final Rejection mailed — §112 (current)

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Prosecution Projections

1-2
Expected OA Rounds
68%
Grant Probability
95%
With Interview (+26.7%)
3y 6m (~1y 6m remaining)
Median Time to Grant
Low
PTA Risk
Based on 619 resolved cases by this examiner. Grant probability derived from career allowance rate.

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