UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(RULE 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☒ Definitive Proxy Statement

☐ Definitive Additional Materials

☐ Soliciting Material under §240.14a-12

5E ADVANCED MATERIALS, INC.

(Name of Registrant as Specified In Its Charter)

N/A

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):

☒ No fee required

☐ Fee paid previously with preliminary materials

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To be held on December 7, 2026

NOTICE IS HEREBY GIVEN that the 2026 Annual Meeting of Stockholders (the “Annual Meeting”) of 5E Advanced Materials, Inc., a Delaware corporation (the “Company”), will be held on December 7, 2026, at 10:00 a.m. Pacific time. To increase access for all of our stockholders, the Annual Meeting will be online and a completely virtual meeting of stockholders. You may attend, vote, and submit questions during the Annual Meeting via the live webcast on the Internet at meetnow.global/FEAM2026. You will not be able to attend the Annual Meeting in person, nor will there be any physical location.

Only stockholders of record at the close of business on October 14, 2026, are entitled to notice of, and to vote at, the Annual Meeting and any postponement or adjournment thereof. We are committed to ensuring our stockholders have the same rights and opportunities to participate in the Annual Meeting as if it had been held in a physical location. As further described in the proxy materials for the Annual Meeting, you may attend the Annual Meeting via the live webcast on the Internet at meetnow.global/FEAM2026. You may vote by telephone, Internet, or mail prior to the Annual Meeting. You will also be able to submit questions in advance of the Annual Meeting by logging in to meetnow.global/FEAM2026 using the 15-digit control number included on your proxy card or on the voting instruction form accompanying these proxy materials. While we encourage you to vote in advance of the Annual Meeting, you may also vote and submit questions relating to meeting matters during the Annual Meeting (subject to time restrictions).

To be admitted to the Annual Meeting at meetnow.global/FEAM2026, you must enter the control number found on your proxy card.

The Annual Meeting will be held for the following purposes:

to serve until the 2027 annual meeting of stockholders (the “2027 Annual Meeting”) and until their respective successors are duly elected and qualified or until such director’s earlier death, resignation, disqualification or removal;

This Notice of Annual Meeting and Proxy Statement is first being distributed or made available, as the case may be, on or about October 26, 2026. The Proxy Statement and our 2026 Annual Report are available at www.edocumentview.com/FEAM. The Notice of Internet Availability of Proxy Materials (“Notice”) provides instructions on how to vote online or by telephone and how to receive a paper copy of your proxy materials by mail.

TABLE OF CONTENTS

FORWARD-LOOKING STATEMENTS

This Proxy Statement contains various forward-looking statements that are not historical facts. These forward-looking statements generally are identified by the words “believe,” “project,” “expect,” “anticipate,” “intend,” “budget,” “target,” “aim,” “strategy,” “estimate,” “plan,” “guidance,” “outlook,” “may,” “should,” “could,” “will,” “would,” “will be,” “will continue,” “will likely result,” and similar expressions, although not all forward-looking statements contain these identifying words. Forward-looking statements reflect the Company and management’s beliefs and expectations based on current estimates and projections. While the Company believes these expectations, and the estimates and projections on which they are based, are reasonable and were made in good faith, these statements are subject to numerous risks and uncertainties, any of which could cause the Company’s actual results, performance, or achievements, or industry results, to differ materially from any future results, performance, or achievements expressed or implied by such forward-looking statements. All statements other than statements of historical fact contained in this Proxy Statement are forward-looking statements, including without limitation, statements regarding the Company’s business model and growth strategy, ability to attract and retain high-quality talent, and purpose and intent involving executive compensation. Forward-looking statements involve known and unknown risks and uncertainties, which include, but are not limited to, the risks described in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2026, under the heading “Risk Factors,” as such risk factors may be updated from time to time in other documents filed by the Company with the Securities and Exchange Commission (the “SEC”).

These forward-looking statements speak only as of the date hereof, and except as required by law, the Company undertakes no obligation to correct, update, or revise any forward-looking statement, whether as a result of new information, future events, or otherwise. You are advised, however, to consult any additional disclosures we make in our reports to the SEC. All subsequent written and oral forward-looking statements attributable to us or persons acting on our behalf are expressly qualified in their entirety by the cautionary statements contained in such disclosures and in our reports to the SEC.

2026 PROXY STATEMENT SUMMARY

This summary contains highlights about our upcoming 2026 Annual Meeting of Stockholders. This summary does not contain all of the information that you may wish to consider in advance of the meeting, and we encourage you to read the entire Proxy Statement before voting.

2026 Annual Meeting of Stockholders

* Our Annual Meeting will be conducted via live webcast. You may attend, ask questions relating to meeting matters, and vote during the Annual Meeting via the live webcast on the Internet at the link above (subject to time restrictions). You will not be able to attend the Annual Meeting in person. There will be no physical location for stockholders to attend.

Voting Matters and Board Recommendations

9329 Mariposa Road, Suite 210

Hesperia, CA 92344

PROXY STATEMENT

ANNUAL MEETING OF STOCKHOLDERS

December 7, 2026

This Proxy Statement and 2026 Annual Report are being furnished to the stockholders of 5E Advanced Materials, Inc. (the “Company” or “5E Materials”) in connection with the solicitation of proxies for the Company’s 2026 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on December 7, 2026, at 10:00 a.m. Pacific time, or at any adjournment or postponement thereof, for the purposes set forth herein. The Annual Meeting will be held via live webcast on the Internet at meetnow.global/FEAM2026. This solicitation is being made by the board of directors of the Company (the “Board of Directors” or the “Board”). You will be able to vote and submit questions online through the virtual-meeting platform during the Annual Meeting by visiting meetnow.global/FEAM2026 and entering your control number included in your Notice of Internet Availability of Proxy Materials, on your proxy card or on the instructions that accompanied your proxy materials.

This Proxy Statement is first being distributed or made available, as the case may be, on or about October 26, 2026.

THE INFORMATION PROVIDED IN THE “QUESTIONS AND ANSWERS” FORMAT BELOW IS FOR YOUR CONVENIENCE AND INCLUDES ONLY A SUMMARY OF CERTAIN INFORMATION CONTAINED IN THIS PROXY STATEMENT. YOU SHOULD READ THIS ENTIRE PROXY STATEMENT CAREFULLY.

QUESTIONS AND ANSWERS

Why am I receiving these materials?

We are distributing our proxy materials because our Board is soliciting your proxy to vote at the Annual Meeting. This Proxy Statement summarizes the information you need to vote at the Annual Meeting. You do not need to attend the Annual Meeting to vote your shares.

Why did I receive a notice regarding the availability of proxy materials on the internet?

As permitted by SEC rules, 5E Materials is making this proxy statement and its 2026 Annual Report available to its stockholders electronically via the Internet. On or about October 26, 2026, we first mailed to our stockholders a Notice of Internet Availability of Proxy Materials (the “Internet Notice”) containing instructions on how to access this proxy statement and our 2026 Annual Report and vote online. If you received an Internet Notice by mail, you will not receive a printed copy of the proxy materials in the mail unless you specifically request them. Instead, the Internet Notice instructs you on how to access and review all of the important information contained in this proxy statement and 2026 Annual Report. The Internet Notice also instructs you on how you may submit your proxy over the Internet. If you received an Internet Notice by mail and would like to receive a printed copy of our proxy materials, you should follow the instructions for requesting such materials contained in the Internet Notice.

How can I attend the Annual Meeting?

Stockholders of record at the close of business on October 14, 2026 (the “Record Date”) (or their duly appointed proxy holder) may attend, vote, and submit questions virtually during the Annual Meeting by logging in at meetnow.global/FEAM2026. To log in, stockholders (or their authorized representatives) will need the control number provided on their proxy card. If you are not a stockholder or do not have a control number, you may still access the meeting as a guest, but you will not be able to submit questions or vote at the meeting. The meeting will begin promptly at 10:00 a.m. Pacific time on December 7, 2026. We encourage you to access the meeting prior to the start time. Online access will open at 9:45 a.m. Pacific time and you should allow ample time to log in to the meeting webcast and test your computer audio system. We recommend that you carefully review the procedures needed to gain admission in advance.

Can I ask questions at the virtual Annual Meeting?

Only registered stockholders as of the Record Date who have accessed our virtual Annual Meeting as a stockholder (rather than as a “guest”) will have an opportunity to submit questions live via the Internet during a designated portion of the meeting. We also encourage you to submit questions in advance of the meeting until 11:59 p.m. Eastern time the day before the Annual Meeting by going to meetnow.global/FEAM2026 and logging in with your control number. During the meeting, we will spend up to 15 minutes answering stockholder questions that comply with the meeting rules of procedure. The rules of procedure, including the number and types of questions that will not be accepted, will be posted on the Annual Meeting website. To provide for orderly conduct of the Annual Meeting, we encourage you to submit questions in advance. If we receive substantially similar questions, we will group such questions together and provide a single response to avoid repetition. Stockholders must have available their control number provided on their proxy card to ask questions during the meeting.

What if I have technical difficulties or trouble accessing the virtual Annual Meeting?

We will have technicians ready to assist you with any technical difficulties you may have accessing the virtual meeting. If you encounter any difficulties accessing the virtual meeting during check-in or during the meeting, please call the technical support number that will be posted on the virtual stockholder meeting login page: meetnow.global/FEAM2026.

What proposals will be voted on at the Annual Meeting?

Stockholders will vote on four (4) proposals at the Annual Meeting:

to serve until the 2027 annual meeting of stockholders (the “2027 Annual Meeting”) and until their respective successors are duly elected and qualified or until such director’s earlier death, resignation, disqualification or removal (“Proposal One”);

We will also consider other business, if any, that properly comes before the Annual Meeting.

What happens if other business not discussed in this Proxy Statement comes before the meeting?

The Company does not know of any business to be presented at the Annual Meeting other than the proposals discussed in this Proxy Statement. If other business properly comes before the meeting under our Amended and Restated Certificate of Incorporation (the “Charter”), Second Amended and Restated Bylaws (the “Bylaws”), and rules established by the SEC, the proxies will use their discretion in casting all the votes that they are entitled to cast.

How does the Board recommend that stockholders vote on the proposals?

Our Board recommends that stockholders vote:

Who is entitled to vote?

As of the Record Date, 49,634,871 shares of common stock, par value $0.01 per share (“Common Stock”), were outstanding. Only holders of record of our Common Stock as of the Record Date will be entitled to notice of, and to vote at, the Annual Meeting or any

adjournment or postponement thereof. Each stockholder is entitled to one vote for each share of our Common Stock held by such stockholder on the Record Date. No cumulative voting rights are authorized.

How do I vote in advance of the Annual Meeting?

If you are a holder of record of shares of Common Stock of the Company, you may direct your vote without attending the Annual Meeting by following the instructions on the Internet Notice or, if you requested paper copies, the proxy card to vote by Internet or by telephone, or by signing, dating, and mailing a proxy card.

If you hold your shares in street name via a broker, bank, or other nominee, you may direct your vote without attending the Annual Meeting by following the instructions on the Internet Notice or, if you requested paper copies, the signing, dating, and mailing your voting instruction card. Internet or telephonic voting may also be available. Please see your Internet Notice or voting instruction card provided by your broker, bank, or other nominee for further details.

How do I vote during the Annual Meeting?

Shares held directly in your name as the stockholder of record may be voted if you are attending the Annual Meeting by entering the control number found on the Internet Notice or, if you requested paper copies, your proxy card when you log in to the meeting at meetnow.global/FEAM2026.

Shares held in street name through a brokerage account or by a broker, bank, or other nominee may only be voted at the Annual Meeting by submitting voting instructions to your bank, broker or other nominee or by presenting a legal proxy, issued in your name from the record holder (your bank, broker or other nominee).

Even if you plan to attend the Annual Meeting, we recommend that you vote in advance, as described above under “How do I vote in advance of the Annual Meeting?” so that your vote will be counted if you are unable to attend the Annual Meeting.

Can I change my vote or revoke my proxy?

You may change your vote or revoke your proxy at any time before it is voted at the Annual Meeting. If you are a stockholder of record, you may change your vote or revoke your proxy by:

If your shares are held in the name of a bank, broker, or other nominee, you may change your vote by submitting new voting instructions to your bank, broker, or other nominee. Please note that if your shares are held of record by a bank, broker, or other nominee and you decide to attend and vote at the Annual Meeting, your vote at the Annual Meeting will not be effective unless you present a legal proxy, issued in your name from the record holder (your bank, broker, or other nominee).

What is a broker non-vote?

Brokers, banks, or other nominees holding shares on behalf of a beneficial owner may vote those shares in their discretion on certain “routine” matters even if they do not receive voting instructions from the beneficial owner. With respect to “non-routine” matters, the broker, bank, or other nominee is not permitted to vote shares for a beneficial owner without voting instructions.

A broker non-vote occurs when a broker, bank, or other nominee does not vote on a non-routine matter because the beneficial owner of such shares has not provided voting instructions with regard to such matter. A broker, bank, or other nominee may exercise its discretionary voting authority on Proposal Two because Proposal Two is a routine matter, and as such, we do not expect any broker non-votes on Proposal Two. Broker non-votes may occur as to the other Proposals. The effect of broker non-votes on each of the other Proposals is described below.

What constitutes a quorum?

The presence at the Annual Meeting, either in person or by proxy, of holders of one-third in voting power of the shares of the Company entitled to vote at the Annual Meeting shall constitute a quorum for the transaction of business. Abstentions and broker non-votes will be counted as present for the purpose of determining whether there is a quorum at the Annual Meeting. Your shares are counted as being present if you participate virtually at the Annual Meeting and cast your vote online during the meeting prior to the closing of the polls by visiting meetnow.global/FEAM2026, or if you vote by proxy via the Internet, by telephone, or by returning a properly executed and dated proxy card or voting instruction form by mail.

What vote is required to approve each matter to be considered at the Annual Meeting?

Proposal One: Election of Five Director Nominees Named in This Proxy Statement.

Our Bylaws provide that the election of directors shall be determined by a majority of the votes cast at the meeting by the holders of stock entitled to vote thereon. Abstentions and broker non-votes will have no effect on Proposal One.

Under our Bylaws, a majority of the votes cast means that the number of shares voted “for” a nominee must exceed the votes cast “against” such nominee. The Nominating and Corporate Governance Committee has established procedures under which a director standing for reelection in an uncontested election must tender a resignation conditioned on the incumbent director’s failure to receive a majority of the votes cast. If an incumbent director who is standing for re-election does not receive a majority of the votes cast, the Nominating and Corporate Governance Committee shall make a recommendation to the Board of Directors on whether to accept or reject the resignation, or whether other action should be taken. The Board of Directors shall act on the committee’s recommendation and publicly disclose its decision and the rationale behind it within 90 days from the date of the certification of the election results.

Proposal Two: Ratification of the Appointment of PricewaterhouseCoopers LLP as Our Independent Registered Public Accounting Firm for the Fiscal Year Ending June 30, 2027.

The proposal to ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the 2027 fiscal year requires approval by the affirmative vote of the majority of shares present in person or represented by proxy at the meeting and entitled to vote on the matter. Abstentions will have the same effect as a vote against Proposal Two. Brokers will have discretionary authority to vote on this proposal. Accordingly, we do not expect any broker non-votes on Proposal Two.

Proposal Three: Approval of an amendment to the Amended and Restated 5E Advanced Materials, Inc. 2022 Equity Compensation Plan to increase the number of shares of Common Stock authorized for issuance.

This proposal shall be determined by the affirmative vote of the majority of shares present in person or represented by proxy at the meeting and entitled to vote on the matter. Abstentions will have the same effect as a vote against Proposal Three, and broker non-votes will have no effect on Proposal Three.

Proposal Four: Approval of the adjournment of the Annual Meeting, if necessary, to solicit additional proxies if there are not sufficient votes in favor of Proposal Three.

This proposal shall be determined by the affirmative vote of the majority of shares present in person or represented by proxy at the meeting and entitled to vote on the matter. Abstentions will have the same effect as a vote against Proposal Four, and broker non-votes will have no effect on Proposal Four.

What is the deadline for submitting a proxy?

So that proxies are received in time to be counted prior to the Annual Meeting, proxies submitted by Internet or by telephone must be received by 11:59 p.m. Eastern time on Sunday, December 6, 2026, and proxies submitted by mail should be received by the close of business on Thursday, December 3, 2026.

What does it mean if I receive more than one proxy card?

If you hold your shares in more than one account, you will receive one proxy card for each account. So that all of your shares are voted, please complete, sign, date, and return one proxy card for each account or use the proxy card for each account to vote by Internet or by telephone.

How will my shares be voted if I return a signed but blank proxy card or voting instruction form or submit a proxy without giving voting instructions?

If you are a holder of record of our Common Stock and you sign and return a proxy card or otherwise submit a proxy without giving specific voting instructions, your shares will be voted:

If you hold your shares in street name via a broker, bank, or other nominee and do not provide the broker, bank, or other nominee with voting instructions (including by signing and returning a blank voting instruction card), your shares:

Our Board knows of no matter to be presented at the Annual Meeting other than the Proposals identified in this Proxy Statement.

Who is making this solicitation and who will pay the expenses?

This proxy solicitation is being made on behalf of our Board. The Company will pay the cost of soliciting proxies for the Annual Meeting. In addition to solicitation by mail, our employees may solicit proxies personally or by telephone or facsimile, but they will not receive additional compensation for these services. Arrangements may be made with brokerage houses, custodians, nominees, and fiduciaries to send proxy materials to their principals, and we may reimburse them for their expenses.

A list of stockholders entitled to vote at the Annual Meeting will be available for inspection by stockholders for any purpose germane to the meeting for 10 business days prior to the Annual Meeting, at 5E Advanced Materials, Inc., 9329 Mariposa Road, Suite 210, Hesperia, CA 92344 between the hours of 9:00 a.m. and 5:00 p.m. Pacific time.

What is “householding” and how does it affect me?

We have adopted a procedure approved by the SEC called “householding.” Under this procedure, we send only one set of proxy materials to eligible stockholders who share a single address, unless we have received instructions to the contrary from any stockholder at that address. This practice is designed to eliminate duplicate mailings, conserve natural resources, and reduce our printing and mailing costs. Stockholders who participate in householding will continue to receive separate proxy cards.

If your shares are held beneficially and you share an address with another stockholder and receive only one set of proxy materials but would like to request a separate copy of these materials, please contact Broadridge Financial Solutions, Inc., by calling (866) 540-7095 or writing to Broadridge Householding Department, 51 Mercedes Way, Edgewood, New York 11717, and an additional copy of proxy materials will be promptly delivered to you. Similarly, if you receive multiple copies of the proxy materials and would prefer to receive a single copy in the future, you may also contact Broadridge at the above telephone number or address. If you own shares through a bank, broker, or other nominee, you should contact the nominee concerning householding procedures.

Where can I find the 2026 Annual Report?

Our 2026 Annual Report, including our Annual Report on Form 10-K for the fiscal year ended June 30, 2026, is being mailed with this Proxy Statement to those stockholders that receive this Proxy Statement in the mail.

Our Annual Report on Form 10-K for the fiscal year ended June 30, 2026 has also been filed with the SEC. It is available free of charge at the SEC’s website at www.sec.gov. Upon written request by a stockholder, we will mail without charge a copy of our Annual Report on Form 10-K, including the financial statements and financial statement schedules, but excluding exhibits. Exhibits to the Annual Report on Form 10-K are available upon payment of a reasonable fee, which is limited to our expenses in furnishing the requested exhibit. All requests should be directed to the Corporate Secretary at 9329 Mariposa Road, Suite 210, Hesperia, California 92344.

How can I find out the results of the voting at the Annual Meeting?

We will announce preliminary voting results at the Annual Meeting. We will also disclose voting results on a Current Report on Form 8-K that we will file with the SEC within four business days after the Annual Meeting.

When are stockholder proposals due for the 2027 Annual Meeting of the stockholders?

Rule 14a-8 Shareholder Proposals. Stockholders who intend to have a proposal considered for inclusion in our proxy materials for presentation at our 2027 Annual Meeting of Stockholders pursuant to Rule 14a-8 under the Securities Exchange Act of 1934, as amended (the “Exchange Act”) must submit the proposal to our executive offices at 9329 Mariposa Road, Suite 210, Hesperia, California 92344 in writing not later than June 28, 2027.

Proxy Access. Under our Bylaws, if you wish to nominate a director through proxy access, you must give timely written notice to our Secretary at the principal executive offices of the Company. To be timely, notice must be delivered to the Secretary not later than 120 days nor more than 150 days prior to the first anniversary of the date that our definitive proxy statement was first sent to stockholders in connection with the preceding year’s annual meeting of stockholders. For the 2027 Annual Meeting of Stockholders, written notice must be received by the Secretary between the close of business on May 29, 2027, and the close of business on June 28, 2027. In the event that the 2027 Annual Meeting of Stockholders is advanced by more than 30 days or delayed by more than 60 days from the anniversary of the preceding year’s annual meeting, or if no annual meeting was held in the preceding year, notice must be delivered to the Secretary not earlier than the close of business on the 150th day prior to such annual meeting and not later than the close of business on the later of (i) the 120th day prior to such annual meeting or (ii) the 10th day following the day on which public disclosure

of the date of such annual meeting is first made by us. Such notices must comply with the procedural and content requirements of our Bylaws, a copy of which is available upon request to our Secretary.

Proposals or Director Nominees (other than through Proxy Access). Stockholders intending to present a proposal of business at the 2027 Annual Meeting of Stockholders, but not to include the proposal in our proxy statement, or to nominate a person for election as a director, must comply with the requirements set forth in our Bylaws. Our Bylaws require, among other things, that the stockholder of record deliver their intent to present such proposal or nomination to the Secretary at the principal executive offices of the Company (A) not later than the close of business on the 90th day, nor earlier than the close of business on the 120th day, in advance of the anniversary of the previous year’s annual meeting, if such meeting is to be held on a day which is not more than 30 days in advance of the anniversary of the previous year’s annual meeting or not later than 60 days after the anniversary of the previous year’s annual meeting, and (B) with respect to any other annual meeting of stockholders, including in the event that no annual meeting was held in the previous year, not earlier than the close of business on the 120th day prior to the annual meeting and not later than the close of business on the later of the 90th day prior to the annual meeting and the close of business on the 10th day following the first date of public disclosure of the date of such meeting. For the 2027 Annual Meeting of Stockholders, the Secretary must receive notice of such a proposal or nomination no earlier than the close of business on August 9, 2027, and no later than the close of business on September 8, 2027. The notice must contain the information required by our Bylaws, a copy of which is available upon request to our Secretary.

SEC rules permit management to vote proxies in its discretion in certain cases if the stockholder does not comply with the above deadlines and, in certain other cases notwithstanding the stockholder’s compliance with these deadlines.

In addition to satisfying the foregoing requirements under our Bylaws, to comply with the universal proxy rules, stockholders who intend to solicit proxies in support of director nominees other than the Company’s nominees must provide notice that sets forth the additional information required by Rule 14a-19(b) of the Exchange Act.

We reserve the right to reject, rule out of order, or take other appropriate action with respect to any proposal that does not comply with these or other applicable requirements.

In connection with our solicitation of proxies for our 2027 Annual Meeting, we intend to file a proxy statement and WHITE proxy card with the SEC. Stockholders may obtain our proxy statement (and any amendments and supplements thereto) and other documents as and when filed with the SEC without charge from the SEC’s website at: www.sec.gov.

Who can I contact for further information?

You may request additional copies, without charge, of this Proxy Statement and other proxy materials or ask questions about the Annual Meeting, the proposals, or the procedures for voting your shares by writing to our Corporate Secretary at 9329 Mariposa Road, Suite 210, Hesperia, California 92344.

Unless indicated otherwise, all share and per share numbers in this Proxy Statement reflect our 1-for-23 reverse stock split effected in February 2025.

MATTERS TO BE CONSIDERED AT THE ANNUAL MEETING

PROPOSAL ONE (1) TO (5)

ELECTION OF DIRECTORS

General

At the Annual Meeting, our stockholders will vote on five directors for a one-year term and until the election and qualification of their respective successors in office, or until such director’s earlier death, resignation, disqualification or removal.

The directors named herein have agreed to serve, if elected, until the next annual meeting of stockholders and until their successors have been duly elected and qualified or until their earlier death, resignation, disqualification or removal. There are no family relationships between or among any of our executive officers, nominees, or continuing directors. Mr. Hébert and Mr. van’t Hoff, two of our director nominees, were initially recommended to serve as members of our Board by BEP Special Situations IV LLC (“Bluescape”) pursuant to Bluescape designation rights described elsewhere in this proxy statement. On April 13, 2026, Mr. Siegler was appointed to the Board, having been designated for appointment by Bluescape designation rights described elsewhere in this proxy statement, and he succeeds Mr. van’t Hoff as one of Bluescape’s designees and serves alongside Mr. Herbert. Each of the director nominees was evaluated in accordance with our standard review process for director candidates in connection with their nomination for election at the Annual Meeting.

The election of each nominee will be voted on separately.

Director Nominees

The following table sets forth information with respect to our director nominees for election at the Annual Meeting:

Director Nominee Skills Matrix

More detailed biographical descriptions of the nominees are set forth in the text below. These descriptions include the experience, qualifications, qualities, and skills that led to the conclusion that each director should serve as a member of our Board at this time.

Our directors bring a range of skills and experience in relevant areas, including finance, exploration and production, environment, international business and leadership, as well as specialty chemicals. We believe this cross-section of capabilities enables our Board of Directors to help guide our objectives and corporate governance practices.

Recommendation of Our Board of Directors

OUR BOARD OF DIRECTORS RECOMMENDS THAT OUR STOCKHOLDERS VOTE “FOR” THE ELECTION OF EACH NOMINEE NAMED ABOVE.

CORPORATE GOVERNANCE

Our Board believes sound corporate governance processes and practices, as well as high ethical standards, are critical to handling challenges and to achieving business success. We embrace leading governance practices and conduct ongoing reviews of our governance structure and processes to reflect changing circumstances. Below are highlights of our corporate governance practices and principles.

Director Independence

Our Common Stock is listed on the Nasdaq Stock Market (the “Nasdaq”). Under the rules of the Nasdaq, a director will only qualify as an “independent director” if the board of directors determines that the director has no relationship which would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In addition, the director must not be precluded from qualifying as independent under the per se bars set forth by the Nasdaq rules.

Audit Committee members must also satisfy the independence criteria set forth in Rule 10A-3 under the Exchange Act. In order to be considered independent for purposes of Rule 10A-3, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the board of directors, or any other board committee, (1) accept, directly or indirectly, any consulting, advisory, or other compensatory fee from the listed company or any of its subsidiaries or (2) be an affiliated person of the listed company or any of its subsidiaries.

At least annually, our Board evaluates all relationships between us and each director in light of relevant facts and circumstances for the purposes of determining whether a relationship exists that might interfere with such director’s ability to satisfy his or her responsibilities as an independent director. Based on this evaluation, our Board will make an annual determination of whether each director is independent within the meaning of the independence standards of Nasdaq and the SEC.

Consistent with our corporate governance guidelines and Nasdaq rules, our Board has determined that each of Messrs. Dick, Hébert, Jones, van’t Hoff and Siegler qualifies as an “independent director.” Our Board also has determined that Messrs. Dick, Hébert, Jones, and van’t Hoff, who currently serve on our Audit Committee, Compensation Committee, and Nominating and Corporate Governance Committee, satisfy the applicable independence standards for such committee service established by the SEC and the rules of Nasdaq. In making such determinations, our Board considered the relationships that each non-employee director has with our Company and all other facts and circumstances our Board deemed relevant in determining independence, including the beneficial ownership of our capital stock by each non-employee director and any institutional stockholder with which he or she is affiliated.

Board Leadership Structure

Our Corporate Governance Guidelines provide the Board will conduct an annual assessment of its leadership structure to determine that the leadership structure is the most appropriate for the Company. The Chairman of the Board and CEO positions may, but need not, be filled by the same individual. At this time, the offices of the Chairman of the Board and the CEO are not combined. If the offices were combined, the Board would appoint a lead independent director to coordinate the activities of the other independent directors and to perform such other duties and responsibilities as the Board may determine. Graham van’t Hoff currently serves as Chairman of the Board.

Role of the Board in Risk Oversight

The Board is responsible for the oversight of risk, while management is responsible for the day-to-day management of risk. The Board, directly and through its committees, carries out its oversight role by regularly reviewing and discussing with management the risks inherent in the operation of our business and applicable risk mitigation efforts. Management meets regularly to discuss the Company’s business strategies, challenges, risks and opportunities and reviews those items with the Board at regularly scheduled meetings. The Compensation Committee is responsible for overseeing the management of risks relating to our compensation plans and arrangements, including whether the Company’s incentive compensation plans encourage excessive or inappropriate risk taking. The Audit Committee is responsible for overseeing our risk assessment and management processes related to, among other things, our financial reports and record-keeping, major litigation and financial risk exposures, and cybersecurity risk, and the steps management has taken to monitor and control such exposures. The Nominating and Corporate Governance Committee is responsible for risk oversight associated with corporate governance practices and the composition of our Board and its committees.

Evaluations of the Board of Directors

The Board evaluates its performance and the performance of its committees and individual directors on an annual basis through an evaluation process administered by our Nominating and Corporate Governance Committee. The Board discusses each evaluation to determine what, if any, actions should be taken to improve the effectiveness of the Board or any committee thereof or of the directors.

Board and Committee Meetings and Attendance

Directors are expected to make every effort to attend all meetings of the Board and all meetings of the committees on which they serve. During fiscal year ended June 30, 2026 (“fiscal year 2026”), our Board had eight Board meetings, our Audit Committee had four meetings, our Nominating and Corporate Governance Committee had one meeting and our Compensation Committee had three meetings. During fiscal year 2026, each current member of our Board attended at least 75% of all Board and relevant committee meetings held during the period in which such director served. Our independent directors hold regularly scheduled executive sessions without our management present. These executive sessions of independent directors are chaired by our Chairman of the Board.

Board Attendance at Annual Stockholders’ Meeting

Each director is encouraged and generally expected to attend the Company’s annual meeting of stockholders, and two directors attended last year’s annual meeting of stockholders.

Board Committees

Our Board has established an Audit Committee, a Compensation Committee and a Nominating and Corporate Governance Committee. The composition and responsibilities of each of the committees of our Board are described below. Copies of the charters of the committees are available on the investor relations page of our website at https://5eadvancedmaterials.com/investors/corporate-governance/. The information in or accessible through our website is not incorporated into, and is not considered part of, this Proxy Statement. Members serve on these committees until their resignation or until otherwise determined by our Board. Our Board may establish other committees as it deems necessary or appropriate from time to time.

Current Committee Composition and Meeting Information for Fiscal Year 2026

The following table provides current membership and meeting information for fiscal year 2026 for each of these committees of our Board with directors marked with an asterisk (*) identified as committee chair:

Audit Committee

Messrs. Dick, Jones and van't Hoff are the current members of the Audit Committee. Mr. Dick is the Chairman of the Audit Committee. Our Board has determined that each current and prospective member of the Audit Committee qualifies as an independent director under the Nasdaq corporate governance standards and the independence requirements of Rule 10A-3 of the Exchange Act and meets the requirements for financial literacy for service on an Audit Committee, as defined under applicable Nasdaq rules. Our Board has determined that each of Messrs. Dick, Jones and van't Hoff qualify as an “audit committee financial expert” as such term is defined in Item 407(d)(5) of Regulation S-K, and that each of the members meets the requirements for financial literacy for service on an Audit Committee, as defined under applicable Nasdaq rules.

Under its charter, the functions of the Audit Committee include, among other things:

Compensation Committee

Messrs. Jones, Hébert and Dick are the current members of the Compensation Committee. Mr. Jones is the Chairman of the Compensation Committee. The Board has determined that each of Messrs. Jones, Hébert and Dick, qualifies as an independent director and is considered to be a “non-employee director” under Rule 16b-3 of the Exchange Act.

Under its charter, the functions of the Compensation Committee include, among other things:

The Compensation Committee charter also provides that the Compensation Committee shall have the sole authority to retain or obtain the advice of a compensation consultant, legal counsel or other adviser. However, before engaging or receiving advice from a compensation consultant, external legal counsel or any other adviser, the Compensation Committee will consider the independence of each such adviser.

Nominating and Corporate Governance Committee

Messrs. Hébert, Dick and van't Hoff are the current members of the Nominating and Corporate Governance Committee. Mr. Hébert is the Chairman of the Nominating and Corporate Governance Committee. The Board has determined that each of Messrs. Hébert, Dick and van't Hoff qualifies as an independent director.

Under its charter, the functions of the Nominating and Corporate Governance Committee include, among other things:

The Nominating and Corporate Governance Committee has the sole authority to retain and terminate any search firm to be used to identify director candidates and shall have sole authority to approve the search firm’s fees and other retention terms.

The Nominating and Corporate Governance Committee meets periodically to assess, develop and communicate with the full Board concerning the appropriate criteria for nominating and appointing directors, including the Board’s size and composition, corporate governance policies, applicable listing standards and laws, individual director performance, expertise, experience, qualifications, attributes, skills, tenure and willingness to serve actively, the number of other public and private Company Boards on which a director candidate serves, consideration of director nominees proposed or recommended by stockholders and related policies and procedures, and other appropriate factors. Whenever a new seat or a vacated seat on the Board is being filled, candidates that appear to best fit the needs of the Board and the Company will be identified, interviewed and evaluated by the Nominating and Corporate Governance Committee. Potential director candidates recommended by the Company’s management and stockholders are evaluated in the same manner as nominees identified by the Nominating and Corporate Governance Committee. Candidates selected by the Nominating and Corporate Governance Committee will then be recommended to the full Board.

Director Recommendations by Stockholders

Recommendations of persons for election to the Board may be made by any stockholder of the Company. All candidates, regardless of the source of their recommendation, are evaluated in the same manner as nominees identified by the Nominating and Corporate Governance Committee.

Election of Directors

We have voluntarily adopted a majority-voting standard for uncontested elections of directors. Our Bylaws provide that, unless otherwise required by law or our Charter or Bylaws, the election of our directors will be decided by a majority of the votes cast at a meeting of the stockholders by the holders of stock entitled to vote in the election, unless our Secretary determines that the number of nominees for director exceeds the number of directors to be elected, in which case directors will be elected by a plurality of the votes of the shares represented in person or by proxy at any meeting of stockholders held to elect directors and entitled to vote on such election of directors.

If a nominee for director who is not an incumbent director does not receive a majority of the votes cast, the nominee will not be elected. Our Nominating and Corporate Governance Committee has established procedures under which a director standing for reelection in an uncontested election must tender a resignation conditioned on the incumbent director’s failure to receive a majority of the votes cast. If an incumbent director who is standing for reelection does not receive a majority of the votes cast, the Nominating and Corporate Governance Committee will make a recommendation to the Board of Directors on whether to accept or reject the resignation, or whether other action should be taken. The Board of Directors must act on the committee’s recommendation and publicly disclose its decision and the rationale behind it within 90 days from the date of the certification of the election results. The director who fails to receive a majority vote is not permitted to participate in the committee’s recommendation or the Board of Directors’ decision.

Corporate Governance Guidelines and Code of Business Conduct

We have adopted Corporate Governance Guidelines and a written Code of Business Conduct (the “Code of Conduct”), which are available on our website at https://investors.5eadvancedmaterials.com/governance-documents. The information in or accessible through our website is not incorporated into, and is not considered part of, this Proxy Statement.

Our Corporate Governance Guidelines provide the framework for our corporate governance along with our Charter, Bylaws, committee charters and other key governance practices and policies. Our Corporate Governance Guidelines cover a wide range of subjects, including the conduct of Board meetings, independence and selection of directors, Board membership criteria, and Board committee composition.

Our Code of Conduct is applicable to our directors, executive officers and employees, including our principal executive officer, principal financial officer or controller, or persons performing similar functions. The Code of Conduct codifies the business and ethical principles that govern all aspects of the Company’s business. Any waiver of this Code of Conduct for any individual director or officer of our Company must be approved, if at all, by our Board of Directors or a duly authorized committee. We intend to make any

legally required disclosures regarding amendments to, or waivers of, provisions of our Code of Conduct on our website rather than by filing a Current Report on Form 8-K.

Insider Trading Policy

Our Board has adopted an Insider Trading Compliance Policy (the “Insider Trading Policy”), that governs the purchase, sale and/or other disposition of the Company’s securities by our directors, officers, employees and consultants. We believe our Insider Trading Policy is reasonably designed to promote compliance with insider trading laws, rules and regulations, as well as listing standards applicable to the Company. In addition, with regard to the Company’s trading in its own securities, it is the Company’s policy to comply with the federal securities laws and the applicable exchange listing requirements. The foregoing summary of the Insider Trading Policy does not purport to be complete and is qualified in its entirety by reference to the full text of the Insider Trading Policy attached as Exhibit 19.1 to our Annual Report on Form 10-K for the fiscal year ended June 30, 2026.

Prohibition on Hedging and Pledging of Company Securities

Our Insider Trading Policy, among other things, prohibits officers, directors, and employees from engaging in hedging transactions, such as the purchase or sale of puts or calls, or the use of any other derivative instruments. Officers, directors, and employees of the Company are also prohibited from including Company securities in a margin account or pledging Company securities as collateral for a loan, unless approved in advance by the Board as to directors and executive officers and by the Corporate Secretary as to other persons covered by the Insider Trading Policy.

Stockholder Communications

Any stockholder or other interested party who wishes to communicate with our Board or any individual director may send written communications to our Board or such director, care of 5E Advanced Materials, Inc., 9329 Mariposa Road, Suite 210, Hesperia, California 92344, Attention: Corporate Secretary. Our Corporate Secretary shall initially review and compile all such communications and may summarize such communications prior to forwarding to the appropriate party. Our Corporate Secretary will not forward communications that are not relevant to the duties and responsibilities of the Board. The Board will generally respond, or cause the Company to respond, in writing to bona fide communications from stockholders addressed to one or more members of the Board.

CERTAIN RELATIONSHIPS AND RELATED PERSON TRANSACTIONS

Policies and Procedures with Respect to Related Party Transactions

The Company’s Audit Committee charter requires that the Audit Committee review and approve or disapprove all related person transactions that are required to be disclosed by Item 404 of Regulation S-K. The Company reviews all relationships and transactions reported to it in which the Company and our directors and executive officers or their immediate family members or any person who is known by the Company to be the beneficial owner of more than five percent (5%) of our voting stock are participants to determine whether such persons have a direct or indirect material interest. The Company’s Secretary is primarily responsible for the development and implementation of processes and controls to obtain information from the directors and executive officers with respect to related person transactions and for then determining, based on the facts and circumstances, whether the Company or a related person has a direct or indirect material interest in the transaction. All historical share amounts set forth in this proxy have been adjusted, as applicable, for the 1-for-23 reverse stock split we effected in February 2025.

Our Board of Directors has adopted a policy regarding transactions affecting director independence as part of a comprehensive governance program. This policy regarding transactions between us or any of our affiliates and our directors, officers, and employees is set forth in writing in our Corporate Governance Guidelines and our Code of Business Conduct. These documents are available on our website. The Board of Directors believes these documents promote the effective functioning of the Board, its committees, and management. Accordingly, they are periodically reviewed and revised, as appropriate.

Certain Relationships and Related Transactions

Described below are the transactions and proposed transactions, since the beginning of our fiscal year ended June 30, 2024, in which we were or are to be a participant and in which any related person has or will have a direct or indirect material interest involving the lesser of $120,000 and one percent (1%) of the average of our total assets as of year end for the last two completed fiscal years. A related person is any executive officer, director, nominee for director, or holder of 5% or more of our Common Stock, or an immediate family member of any of those persons.

As of June 30, 2026, Ascend (inclusive of holdings by Meridian Investments Corporation (“Meridian”), to which Ascend is the sole shareholder) and Bluescape beneficially owned approximately 20.1% and 29.2%, respectively, of our outstanding Common Stock. Pursuant to the terms of an investor and registration rights agreement dated January 14, 2025, to which we are a party, each of Bluescape and Ascend has the right to designate two individuals to our Board for so long as it beneficially owns at least 25% of our Common Stock, reducing to one director for so long as it beneficially owns at least 10% of our Common Stock. In April 2026, Mr. Siegler succeeded Graham van’t Hoff as Bluescape’s designee to serve alongside Mr. Hébert who is Bluescape’s second designee. Mr. Dick serves as Ascend’s designee.

Ascend Subscription Agreement

On December 5, 2023, we entered into a subscription agreement with Ascend, pursuant to which Ascend agreed to purchase up to $10.0 million of our Common Stock at a purchase price of $1.025 per share, plus an additional 10% of the shares sold in the offering as a placement fee. On January 18, 2024, we issued 5,365,854 shares (the “Subscription Shares”) of Common Stock to Ascend pursuant to the subscription agreement for an aggregate purchase price of $7.5 million. At the closing, we also granted Ascend registration rights with respect to the Subscription Shares.

Amended and Restated Note Purchase Agreement

On January 18, 2024, in connection with a series of out-of-court restructuring transactions, we entered into an Amended and Restated Note Purchase Agreement (as subsequently amended, the “Amended and Restated Note Purchase Agreement”) with the holders of our 4.50% senior secured convertible notes (the “Noteholders”): Bluescape, Ascend and Meridian. The agreement provided for the amendment of certain terms of our then outstanding $60.0 million aggregate principal amount of 4.50% senior secured convertible notes, including (among other things) to provide for certain adjustments to the conversion rate in the event of certain change of control transactions or other events (a “Make-Whole Adjustment”) and the minimum cash covenant has been waived through June 28, 2024 (the “Covenant Waiver”). In connection therewith, we also entered into an Amended and Restated Investor and Registration Rights Agreement with the Noteholders, pursuant to which we (i) granted the Noteholders certain registration rights for the shares of Common Stock underlying the convertible notes and the Subscription Shares, and (ii) granted the director designation rights to each of Bluescape and Ascend.

Amendment No. 1 to Amended and Restated Note Purchase Agreement

On April 28, 2024, we entered into an amendment to the Amended and Restated Note Purchase Agreement with the Noteholders, pursuant to which the Noteholders agreed to extend the Covenant Waiver through December 31, 2024.

Amendment No. 2 to Amended and Restated Note Purchase Agreement

On May 28, 2024, we entered into a second amendment to the Amended and Restated Note Purchase Agreement, pursuant to which we agreed to (i) issue and sell $3.0 million principal amount of new senior secured convertible notes to each of Bluescape and Ascend (the “June 2024 Notes”), (ii) amend and restate the Amended and Restated Note Purchase Agreement to (among other things) adjust the Make-Whole Adjustment, and (iii) amend and restate the existing Amended and Restated Investor and Registration Rights Agreement to provide for registration rights covering the shares of Common Stock underlying the new notes. The transactions contemplated by Amendment No. 2, including the issuance and sale of the June Notes, closed on June 11, 2024.

Amendment No. 3 to Amended and Restated Note Purchase Agreement

On August 25, 2024, we entered into commitment letters with Bluescape and Ascend, pursuant to which they agreed to purchase $3.0 million principal amount of new senior secured convertible notes, which were subsequently issued and sold on September 16, 2024 (the “September 2024 Notes”) pursuant to an Amended and Restated Note Purchase Agreement. At the closing, we also entered into an Amended and Restated Investor and Registration Rights Agreement to provide for registration rights covering the shares of Common Stock underlying the new notes.

Amendment No. 4 to Amended and Restated Note Purchase Agreement

On January 14, 2025, we entered into a fourth amendment to the Amended and Restated Note Purchase Agreement and agreed, among other things, to (i) issue and sell new senior secured convertible notes in substantially the same form and under the same terms as the September 2024 Notes, in an aggregate principal amount of $5.0 million (the “January 2025 Notes” and, together with the August 2022 Notes, the June 2024 Notes and the September 2024 Notes, the “Convertible Notes”) to the Noteholders, and (ii) amend and restate the Amended and Restated Note Purchase Agreement. The Amended and Restated Note Purchase Agreement also extended the date to which we were required to comply with a financial covenant to maintain a cash balance of at least $7.5 million from December 31, 2024 to March 31, 2025.

Debt Exchange and Related Agreements

On January 14, 2025, we entered into a restructuring support agreement (the “2025 Restructuring Support Agreement”) with Bluescape, Ascend and Meridian in connection with certain restructuring and recapitalization transactions with respect to our capital structure (collectively the “Exchange Transaction”), including our Convertible Notes issued pursuant to the Amended and Restated Note Purchase Agreement.

Pursuant to the 2025 Restructuring Support Agreement, the parties agreed to effect the Exchange Transaction consisting of, among other things:

On March 4, 2025, at a special meeting of stockholders, our stockholders voted in favor of the Exchange Transaction, and on March 5, 2025 the Exchange was completed and resulted in 13,586,524 shares of our Common Stock issued to Bluescape and Ascend, the termination of the Amended and Restated Note Purchase Agreement and the extinguishment of all indebtedness owed by us under the Amended and Restated Note Purchase Agreement.

On March 13, 2025, pursuant to the January 2025 Subscription Agreement, we issued and sold an aggregate of 1,408,173 shares of Common Stock to Bluescape, Ascend and Meridian at a Subscription Price of $3.5507 per share for aggregate net proceeds of $4.9 million. Also pursuant to the January 2025 Subscription Agreement, we issued Restructuring Warrants to purchase up to an aggregate of 5,632,692 shares of Common Stock to Bluescape and Ascend. The Restructuring Warrants are immediately exercisable and expire on March 13, 2026, and have an exercise price per share equal to the Subscription Price.

Participation in August 2025 Public Offering

On August 21, 2025, we completed the public offering of 2,374,481 shares of our Common Stock at a price to the public of $3.50 per share. Each of Bluescape and Ascend purchased 100,000 shares in the offering at $3.50 per share, the same terms as other investors in the offering.

Restructuring Warrant Amendments and Exercise

On December 4, 2025, we entered into amendments to the Restructuring Warrants with each of Bluescape, Ascend and Meridian (the “Warrant Amendments”). The Warrant Amendments permitted each holder to exercise its Restructuring Warrants on a cashless basis after the holder exercised at least 10% of the shares underlying its Restructuring Warrants for cash. On December 4, 2025, each of Bluescape, Ascend and Meridian exercised its Restructuring Warrants in full (10% by cash exercise and 90% by cashless exercise). Under the cashless exercise feature, the number of shares issued upon net exercise was determined using a formula that compared the five-day volume weighted average price of our Common Stock on the date we received notice of the holder’s intent to exercise to the existing warrant exercise price of $3.5507 per share. In connection with these exercises, we issued an aggregate of 1,067,296 shares of Common Stock and received approximately $2.0 million in cash proceeds. Following the exercises, Bluescape, Ascend and Meridian held no remaining Restructuring Warrants.

EXIM Warrants

In November 2025, we submitted an application to the Export-Import Bank of the United States (“EXIM”) for a $10.0 million funding package (the “EMP Loan”) through EXIM’s Engineering Multiplier Program. On December 8, 2025, at our 2025 annual meeting of stockholders, our stockholders approved our entry into a letter agreement (the “Letter Agreement”) to issue warrants to purchase up to 2,816,346 shares of our Common Stock, representing up to $10.0 million of Common Stock at an exercise price of $3.5507 per share (the “EXIM Warrants”), to Bluescape and Ascend, or their respective affiliates (the “Guarantors”), in connection with each Guarantor providing a guarantee or collateral package (the “Guarantee”) to EXIM as a condition to the award of the EMP Loan. On January 7, 2026, we entered into the Letter Agreement with the Guarantors and issued the EXIM Warrants. The EXIM Warrants (i) vest and become exercisable only after the date the Guarantors provide the Guarantee to EXIM, and only in an amount equal to the amount guaranteed by such Guarantor, (ii) expire upon the earlier of the second anniversary of the date the EMP Loan is repaid or the release of the Guarantee, and (iii) do not include an option for the holder to require us to repurchase the EXIM Warrants for their Black-Scholes value in connection with a fundamental transaction. As of the date of this Proxy Statement, the EMP Loan has not been awarded and the Guarantee has not been provided; accordingly, the EXIM Warrants have not vested and no shares are issuable thereunder. We are under no obligation to secure the EMP Loan with the Guarantee and may pursue other security or collateral arrangements with EXIM.

Participation in February 2026 Public Offering

In February 2026, we completed the issuance and sale of an aggregate of 18,000,000 shares of our Common Stock at a price of $2.00 per share. Bluescape purchased 4,000,000 shares in the offering at $2.00 per share, the same terms as other investors in the offering.

Indemnification Agreements

We have entered into agreements to indemnify our directors and executive officers. These agreements will, among other things, require us to indemnify these individuals for certain expenses (including attorneys’ fees), judgments, fines and settlement amounts reasonably incurred by such person in any action or proceeding, including any action by or in our right, on account of any services undertaken by such person on behalf of our Company or that person’s status as a member of our Board of Directors to the maximum extent allowed under Delaware law.

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information with respect to beneficial ownership of the Company’s Common Stock as of October 14, 2026, by each person, or group of affiliated persons, known to the Company to own beneficially more than 5% of the Company’s outstanding Common Stock, each director, each named executive officer, and all the executive officers and directors of the Company as a group. Unless otherwise indicated in the footnotes to the table, the address of each such person is care of the Company, 9329 Mariposa Road, Suite 210, Hesperia, California 92344. Share numbers in the table below, including the footnotes thereto, have been updated to reflect the Company’s 1-for-23 reverse stock split the Company effected in February 2025.

Beneficial ownership is determined in accordance with Rule 13d-3 of the Exchange Act. Shares of Common Stock subject to options currently exercisable or exercisable within 60 days of October 14, 2026, are deemed outstanding for purposes of computing the percentage beneficially owned by such holder but are not deemed outstanding for purposes of computing the percentage beneficially owned by any other person. Except as otherwise indicated, the Company believes that the beneficial owners of the Common Stock listed below, based on information furnished by such owners, have sole investment and voting power with respect to such shares, subject to community property laws where applicable, and that there are no other affiliations among the stockholders listed in the table. The percentage for each beneficial owner is calculated based on (i) the aggregate number of shares reported to be owned by such group or individual and (ii) the aggregate number of shares of Common Stock outstanding as of October 14, 2026 (49,634,871 shares).

Shares Owned by Certain Beneficial Holders

The amounts and percentages of Common Stock beneficially owned are reported on the basis of regulations of the SEC governing the determination of beneficial ownership of securities. Under the rules of the SEC, a person is deemed to be a “beneficial owner” of a security if that person has or shares “voting power,” which includes the power to vote or to direct the voting of such security, or “investment power,” which includes the power to dispose of or to direct the disposition of such security. A person is also deemed to be a beneficial owner of any securities of which that person has the right to acquire beneficial ownership within 60 days. Under these rules, more than one person may be deemed a beneficial owner of the same securities and a person may be deemed to be a beneficial owner of securities as to which such person has no economic interest.

The following table sets forth the information for each person deemed to beneficially own 5% or more of our outstanding Common Stock, based on information regarding the beneficial ownership of Common Stock available to us as of October 14, 2026.

EXECUTIVE OFFICERS

The following information with respect to our executive officers is presented as of October 26, 2026:

Paul Weibel was appointed Chief Executive Officer in June 2024, is an active Certified Public Accountant and previously served as Corporate Secretary from June 2023 to October 2024. Mr. Weibel was appointed as the Manager of 5E Boron Americas, LLC in July 2022 when Fort Cady (California) Corporation converted to a Delaware LLC. Previously, Mr. Weibel was appointed Chief Financial Officer and Treasurer of 5E Advanced Materials, Inc. in November 2021, Chief Financial Officer of Fort Cady (California) Corporation in May 2021 where he oversaw the accounting and financial reporting departments, and director of Fort Cady (California) Corporation in April 2022. Mr. Weibel served as Corporate Secretary of Fort Cady (California) Corporation from August 2021 to April 2022 and Treasurer from April 2022 to June 2022. Previously, Mr. Weibel was the Financial Controller of Genlith, Inc. from January 2017 to May 2021 and Finance Director of the Schooner Investment Group LLC from July 2014 to December 2017. Mr. Weibel holds a Bachelor of Science in Finance and Accounting from Lehigh University College of Business.

Joshua Malm was appointed Chief Financial Officer in October 2024. Previously, Mr. Malm served as Interim Chief Financial Officer, on a contract basis, from June 2024 to October 2024 and as our Interim Chief Accounting Officer, on an independent contract basis, from September 2023 to June 2024. Mr. Malm has served as the Managing Member of Malm Consulting LLC, a public accounting firm that advises companies in the energy, mining and chemical industries since July 2023. Prior to that, Mr. Malm served as the Senior Manager of Technical Accounting from March of 2019, was promoted to Director of Financial Reporting in February 2020, and promoted and served as Financial Controller from September of 2021 until February of 2023 at Chord Energy Corporation (Nasdaq: CHRD), where he joined the company through its acquisition of Whiting Petroleum Corporation (NYSE: WLL) in July of 2022. Prior to Chord Energy Corporation, Mr. Malm was with PricewaterhouseCoopers LLP in Denver, Colorado, where he held various positions in their oil and gas audit practice since 2008. He has over 17 years of accounting experience and is an active Certified Public Accountant. Mr. Malm holds a Bachelor of Science in Business Administration and a Master of Science in Accountancy from the University of Colorado at Boulder.

EXECUTIVE COMPENSATION

Introduction and Named Executive Officers

This section discusses the material components of the executive compensation program for our executive officers who are named in the “Summary Compensation Table” below. During fiscal year 2026, our named executive officers or “NEOs” were:

Summary Compensation Table

The following table presents summary information regarding compensation earned with respect to the fiscal years ended June 30, 2025 and June 30, 2026, by our NEOs.

Narrative to Summary Compensation Table

Annual Base Salary

The compensation of our NEOs is generally determined and approved by our Board. The fiscal year 2026 base salaries of each of our NEOs are described under the subsection titled “—Employment Agreements” below.

Annual Bonus

In addition to base salaries, our NEOs are eligible to receive annual performance-based cash bonuses, which are designed to provide appropriate incentives to our executives to achieve annual corporate goals and to reward our executives for individual achievement towards these goals. The annual performance-based bonus each NEO is eligible to receive is based on the extent to which we achieve

the corporate goals that our Board establishes each fiscal year. At the end of the fiscal year, our Board reviews our performance against each corporate goal and determines the extent to which we achieved each of our corporate goals.

For fiscal year 2026, Messrs. Weibel and Malm were eligible to earn a target annual bonus equal to 60% and 40%, respectively, of the executive’s respective annual base salary.

The corporate goals the Board established for fiscal year 2026 related to liquidity, progression of customer engagement and offtake agreements, operational progress, organizational health and culture, and safety goals. Bonuses are typically determined and paid in the third calendar quarter of the year following our June 30 fiscal year end. For fiscal year 2026, the bonuses for our NEOs paid in the fourth quarter of 2026 are reflected in the Summary Compensation Table above.

Equity-Based Incentive Awards

Our equity-based incentive awards are designed to align our interests and those of our stockholders with those of our employees, including our executive officers. The Board or an authorized committee thereof is responsible for approving equity grants. We grant equity awards under our Amended and Restated 2022 Equity Compensation Plan (the “Incentive Plan”).

In March 2026, Messrs. Weibel and Malm were awarded 10,227 RSUs and 12,784 RSUs, respectively, under our Incentive Plan. The RSUs will vest in three equal installments on September 15, 2026, September 15, 2027 and September 15, 2028, subject to the executives’ continued employment through the applicable vesting date.

In addition, in March 2026, Messrs. Weibel and Malm were awarded a target number of 92,046 PSUs and 38,352 PSUs, respectively, under our Incentive Plan. The PSUs may be earned between 0% to 100% of the target number of PSUs granted upon the achievement of certain financial and operational targets, including (i) construction of a large-scale commercial facility commencing prior to June 30, 2027; (ii) an approved final investment decision in the large-scale commercial facility at a modeled internal rate of return of 18%; and (iii) achievement of the Company’s share price exceeding $8.80 per share, in each case, over the three-year performance period ending on September 15, 2028, subject to the executive’s continued employment through the applicable vesting date.

For a description of any additional accelerated vesting applicable to our NEOs’ stock awards, see “Employment Agreements” below.

Outstanding Equity Awards at Fiscal Year End

The following table sets forth the outstanding equity awards held by our NEOs as of June 30, 2026.

Employment Agreements

We have entered into employment agreements with certain of our executive officers, including our NEOs, which govern the terms of their employment with us.

Paul Weibel

Under the terms of Mr. Weibel's employment agreement, Mr. Weibel is entitled to an annual base salary and is eligible to earn an annual bonus of up to 80% of his then-in-effect base salary (on target performance would result in a bonus payment equal to 40% of Mr. Weibel’s then-in-effect base salary), subject to the achievement of performance objectives as determined by our Board.

Regardless of the manner in which Mr. Weibel’s employment terminates, he is entitled to receive certain accrued amounts previously earned during his employment, including unpaid salary, reimbursement of expenses owed, and accrued but unpaid paid time off and any continuation of benefits required by applicable law.

In addition, Mr. Weibel is entitled to certain severance benefits under his employment agreement, subject to his execution of a release of claims and compliance with post-termination obligations. Pursuant to Mr. Weibel’s employment agreement, upon a termination of his employment by the Company for reasons other than for “cause” (as defined in the employment agreement), Mr. Weibel is entitled to (i) an amount in cash equal to six months of annual base salary, payable in a lump sum, (ii) payment of the COBRA premiums for Mr. Weibel and his eligible dependents for a maximum period of up to 6 months from the date of his termination of employment, and (iii) accelerated vesting of all unvested Company equity awards, provided that any Company equity awards that vest based on the attainment of performance goals will remain outstanding and will be eligible to vest in accordance with the terms of the applicable award agreements.

Joshua Malm

On May 15, 2025, we entered into an employment agreement with our Chief Financial Officer and principal accounting officer, Joshua Malm. Pursuant to the employment agreement, Mr. Malm is entitled to cash compensation of $300,000 per year for his service

as our Chief Financial Officer. Additionally, Mr. Malm is eligible to earn an annual bonus of up to 80% of his then-in-effect base salary (on target performance would result in a bonus payment equal to 40% of Mr. Malm’s then-in-effect base salary), subject to the achievement of performance objectives as determined by the Board.

Regardless of the manner in which Mr. Malm’s employment terminates, he is entitled to receive certain accrued amounts previously earned during his employment, including unpaid salary, reimbursement of expenses owed, and accrued but unpaid paid time off and any continuation of benefits required by applicable law.

In addition, Mr. Malm is entitled to certain severance benefits under his employment agreement, subject to his execution of a release of claims and compliance with post-termination obligations. Pursuant to Mr. Malm’s employment agreement, upon a termination of his employment by the Company for reasons other than for “cause” or by Mr. Malm for “good reason” (each term as defined in the employment agreement), Mr. Malm is entitled to (i) an amount in cash equal to six months of annual base salary, payable in a lump sum, (ii) a pro-rated bonus based on target performance for the portion of the year he was employed, (iii) payment of the COBRA premiums for Mr. Malm and his eligible dependents for a maximum period of up to 6 months from the date of his termination of employment, and (iv) accelerated vesting of all unvested Company equity awards, provided that any Company equity awards that vest based on the attainment of performance goals will remain outstanding and will be eligible to vest in accordance with the terms of the applicable award agreements, provided, further, that in the event such termination occurs during the period commencing on the date that is three (3) months prior to a change in control and ending on the date that is eighteen (18) months following a change in control, any PSUs outstanding where the termination date is within twelve (12) months of the end of their respective performance period(s), and there is a reasonable probability that the respective performance goal(s) for such PSUs would have been achieved at target (or above) absent the change in control, then such PSUs that would have vested within such twelve (12) month period following the change in control shall also vest.

Health and Welfare Benefits; Perquisites

All of our employee executives are eligible to participate in our employee benefit plans, including our medical, dental, vision, disability, and life insurance plans, in each case on the same basis as all of our other employees. We generally do not provide perquisites or personal benefits to our NEOs, except in limited circumstances. Our Board may elect to adopt qualified or non-qualified benefit plans in the future if it determines that doing so is in our best interests.

Retirement Plan

We sponsor a 401(k) plan covering substantially all of our employees, including our NEOs. Employees become eligible to participate in the plan upon completing three months of service and attainment of age 21. Eligible employees may elect to make either pretax or Roth contributions to the plan, subject to limitations set forth in the plan and the Internal Revenue Code of 1986, as amended (the “Code”). We may make safe-harbor matching contributions equal to 100% of the first 4% of employees’ eligible earnings and an additional 50% on the next 2% of employees’ eligible earnings. We also may make discretionary profit-sharing contributions.

Clawback Policy

We have adopted a compensation recovery policy that is compliant with the Nasdaq Listing Rules, as required by the Dodd-Frank Act.

Equity Grant Practices

Compensation of Non-Employee Directors

The following table sets forth the compensation earned by our non-employee directors during the year ended June 30, 2026.

Non-Employee Director Compensation Policy

We maintain a compensation program for our non-employee directors (the “Director Compensation Policy”). This policy is intended to fairly compensate our directors for the time and effort necessary to serve on the Board.

The Director Compensation Policy provides for annual retainer fees and equity awards for our non-employee directors. Each non-employee director will receive an annual cash retainer of $50,000, with the non-employee director serving as chair of the board of directors or lead independent director receiving an additional annual cash retainer of $45,000. The non-employee directors serving as the chairs of the audit, compensation, and nominating and corporate governance committees will receive additional annual cash retainers of $25,000. Non-employee directors serving as members of the audit, compensation, and nominating and corporate governance committees will receive additional annual cash retainers of $15,000.

On the last day of each calendar quarter, each non-employee director will receive a grant of RSUs, with an equivalent cash value as the above cash retainers divided by four, subject to any shareholder approvals required, with the number of RSUs determined by dividing the cash value by the average closing price of the Company’s Common Stock during the applicable calendar quarter (inclusive of the first and last day of such calendar quarter). Such quarterly grants will vest on July 1st following the grant date, subject to continued service through such vesting date. Awards to our non-employee directors will also vest in full (i) immediately upon the effectiveness of a non-employee director’s voluntary resignation of service on the Board, (ii) in the event of a change in control or (iii) upon a non-employee director’s death or disability.

Compensation under our non-employee director compensation program will be subject to the annual limits on non-employee director compensation set forth in the Incentive Plan, as described below.

Securities authorized for issuance under equity compensation plans

The following table sets forth the equity awards outstanding under the Company’s 2022 Equity Compensation Plan (the “Incentive Plan”) as of June 30, 2026. There are no equity awards outstanding under the employee share option plan of the Company’s predecessor, ABR (the “ABR Employee Share Option Plan”).

PROPOSAL TWO

RATIFICATION OF THE APPOINTMENT OF PRICEWATERHOUSECOOPERS LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR THE FISCAL YEAR ENDING JUNE 30, 2027

Our Board and the Audit Committee are asking our stockholders to ratify the appointment by the Audit Committee of PricewaterhouseCoopers LLP (“PwC”), as the independent public accounting firm to conduct the audit of our financial statements for the fiscal year ending June 30, 2027. Stockholder ratification of such appointment is not required by our Bylaws or any other applicable legal requirement. However, our Board is submitting the appointment of PwC to our stockholders for ratification as a matter of good corporate governance.

In the event our stockholders do not ratify the appointment, the Audit Committee will reconsider whether to continue to retain PwC for the fiscal year ending June 30, 2027. Even if the appointment is ratified, the Audit Committee, in its discretion, may direct the appointment of a different independent registered public accounting firm at any time during the year if the Audit Committee believes that such a change should be made. Representatives of PwC are expected to be present at the Annual Meeting and will have an opportunity to make statements if they desire and will be available to respond to appropriate questions.

Principal Accountant Fees and Services

Fees billed by PwC for the fiscal years ended June 30, 2026 and 2025, respectively, are as follows:

Audit fees for the year ended June 30, 2026 include $627,500 paid to PwC for the audit of the Company’s year-end financial statements included in our Annual Report on Form 10-K for the fiscal year ended June 30, 2026, consents, and other items related to SEC matters. Other fees for the year ended June 30, 2026 include $2,000 paid to PwC for accounting research and disclosure software.

Audit fees for the year ended June 30, 2025 include $770,313 paid to PwC for the audit of the Company’s year-end financial statements included in our Annual Report on Form 10-K for the fiscal year ended June 30, 2025, consents, and other items related to SEC matters. Other fees for the year ended June 30, 2025 include $2,132 paid to PwC for accounting research and disclosure software.

Determination of Independence

In considering the nature of the services provided by our independent registered public accounting firm, the Audit Committee determined that such services are compatible with the provision of independent audit services. The Audit Committee discussed these services with our independent registered public accounting firm and our management to determine that they are permitted under the rules and regulations concerning auditor independence.

Additional information concerning the Audit Committee and its activities can be found in the following sections of this Proxy Statement: “Corporate Governance—Audit Committee” and “Report of the Audit Committee.”

Pre-Approval Policy

According to policies adopted by the Audit Committee and ratified by our Board, to facilitate compliance with the SEC’s rules regarding auditor independence, all audit and non-audit services to be provided by our independent registered public accounting firm must be pre-approved by the Audit Committee. The Audit Committee has established a general pre-approval policy for certain audit and non-audit services, up to a specified amount for each identified service that may be provided by the independent auditors.

The Audit Committee approved one hundred percent (100%) of all services provided by PwC during the years ended June 30, 2026 and June 30, 2025, respectively. The Audit Committee has considered the nature and amount of the fees billed by PwC and believes that the provision of the services for activities unrelated to the audit is compatible with maintaining PwC’s independence.

Recommendation of Our Board of Directors and Audit Committee

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMEND THAT OUR STOCKHOLDERS VOTE “FOR” THE RATIFICATION OF THE APPOINTMENT OF PricewaterhouseCoopers LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR THE FISCAL YEAR ENDING JUNE 30, 2026.

REPORT OF THE AUDIT COMMITTEE

Management is responsible for the preparation, presentation, and integrity of the Company’s financial statements, accounting and financial-reporting principles, internal controls and procedures designed to ensure compliance with accounting standards, and applicable laws and regulations. The Audit Committee is responsible for appointing, compensating, overseeing, and, where appropriate, discharging and replacing the Company’s independent registered public accounting firm (the “independent accounting firm”). In addition, the Audit Committee is involved in the selection of the lead audit engagement partner whenever a rotational change is required by applicable law or listing standards or for any other reason. The independent accounting firm is responsible for expressing an opinion on the conformity of the Company’s audited financial statements with generally accepted accounting principles. In addition, once applicable, the independent accounting firm will express its own opinion on the effectiveness of the Company’s internal controls over financial reporting.

The function of the Audit Committee is not intended to duplicate or attest as to the activities of management and the independent accounting firm, nor can the Audit Committee certify that the independent accounting firm is “independent” under applicable rules. The Audit Committee serves a board-level oversight role, in which it provides advice, counsel, and direction to management and the independent accounting firm on the basis of the information it receives, discussions with management and the independent accounting firm, and the experience of the Audit Committee’s members in business, financial, and accounting matters.

In this context, the Audit Committee met and held numerous discussions with management and the independent accounting firm during fiscal year 2026. Management represented to the Audit Committee that the Company’s consolidated financial statements were prepared in accordance with GAAP, and the Audit Committee has reviewed and discussed the consolidated financial statements with management and the independent accounting firm. The Audit Committee discussed with the independent accounting firm matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board. The independent accounting firm also provided to the Audit Committee the written disclosures and the letter required by Rule 3526 of the Public Company Accounting Oversight Board, Communications with Audit Committees Concerning Independence, and the Audit Committee discussed with the independent accounting firm the firm’s independence.

Based upon the Audit Committee’s discussion with management and the independent accounting firm and the Audit Committee’s review of the representations of management and the report of the independent accounting firm on the Consolidated Financial Statements, the Audit Committee recommended that the Board of Directors include the audited consolidated financial statements in the Company’s Annual Report on Form 10-K for the fiscal year ended June 30, 2026, filed with the SEC on September 17, 2026.

PROPOSAL THREE

TO APPROVE AN AMENDMENT TO THE AMENDED AND RESTATED 5E ADVANCED MATERIALS, INC. 2022 EQUITY COMPENSATION PLAN TO INCREASE THE NUMBER OF SHARES OF COMMON STOCK AUTHORIZED FOR ISSUANCE

Introduction

On October 14, 2026, our Board adopted an amendment (the “Plan Amendment”) to the Amended and Restated 5E Advanced Materials, Inc. 2022 Equity Compensation Plan, as amended (the “Incentive Plan”), which increases the aggregate number of shares reserved for issuance under the Incentive Plan by 2,500,000 shares.

We refer to the Incentive Plan, as amended by the Plan Amendment, as the “Amended Plan.” The Plan Amendment is subject to stockholder approval. If approved by our stockholders, the Plan Amendment will become effective as of the date the Board adopted the Plan Amendment (the “Amendment Effective Date”). The Board recommends that you vote “FOR” the approval of the Plan Amendment.

Why Stockholders Should Vote to Approve the Plan Amendment

We do not have any other stock incentive plans pursuant to which equity awards can be granted; however, we previously granted equity awards under the employee share option plan of the Company’s predecessor, ABR (the “ABR Employee Share Option Plan”), all of which expired as of October 1, 2025. We are asking our stockholders to approve the Plan Amendment because we believe the availability of an adequate reserve of shares under the Incentive Plan is an integral part of our compensation program, as well as our continued growth and success. If the Plan Amendment is not approved, we believe the foregoing goals will be adversely affected.

Information on Equity Compensation Plans as of October 14, 2026

The information included in this Proxy Statement and our 2026 Annual Report on Form 10-K is updated by the following information regarding all existing equity compensation plans as of October 14, 2026:

Background of Determination of Shares Under the Plan Amendment

As mentioned above, in its determination to approve the Plan Amendment, the Board was primarily motivated by a desire to ensure the Company has an available pool of shares from which to grant long-term equity-based incentive awards, which the Board believes is an incentive and retention mechanism for our employees, consultants and non-employee directors. The Board considered key factors in making its determination including our historical grant rates, the shares remaining available for issuance under the Incentive Plan, and the potential dilution associated with the Incentive Plan.

This review included a consideration of the following key metrics, factors and philosophies:

If approved by our stockholders, the Plan Amendment would increase the aggregate number of shares available for grant by 2,500,000 shares of Common Stock.

If we exhaust the share reserve under the Incentive Plan without approval of the Plan Amendment, we would lose an important element of our compensation program that is essential to attract, motivate and retain highly qualified talent, and that aligns the interests of our employees with our stockholders.

In light of the factors described above, the Board believes that the size of the share reserve proposed by the Plan Amendment is reasonable and appropriate at this time.

To the extent we grant any awards between October 14, 2026 and the date of this Annual Meeting, the available share reserve under the Amended Plan will be reduced from 2,861,651 shares (i.e., the remaining available reserve as of October 14, 2026 (361,651 shares, assuming the achievement of outstanding PSUs at “target” performance goals) plus 2,500,000 shares) by the number of shares that we grant during such period.

The Amended Plan Combines Compensation and Governance Best Practices

The Amended Plan includes provisions that are designed to protect our stockholders’ interests and to reflect corporate governance best practices including:

Stockholder Approval

As mentioned above, if this Plan Amendment is approved, then as of the Amendment Effective Date, an aggregate of (i) 2,500,000 shares and (ii) any shares which are subject to awards outstanding under the Incentive Plan which become available for issuance under the Amended Plan following the effective date of the existing Incentive Plan will be reserved for issuance pursuant to the Amended Plan. Approval of the Plan Amendment will constitute approval pursuant to the Nasdaq Stock Market stockholder approval requirements applicable to equity compensation plans.

If our stockholders do not approve the Plan Amendment pursuant to this Proposal Three, the additional shares proposed by the Plan Amendment will not become available for issuance and the existing Incentive Plan (not as amended by the Plan Amendment) will continue in full force and effect, without giving effect to the Plan Amendment, and we may continue to grant equity-based awards under the Incentive Plan subject to shares remaining available for grant under the Incentive Plan.

Material Terms of the Amended Plan

Summary of the Amended Plan

This section summarizes certain principal features of the Amended Plan. The summary is qualified in its entirety by reference to the complete text of the Plan Amendment, which is attached hereto as Appendix A, and the Incentive Plan, as amended, which is attached hereto as Appendix B.

Eligibility; Administration

Employees and non-employee directors of our Company or any of its affiliates and consultants, advisers or other persons or entities that can be granted an award that is eligible to be registered on a Form S-8 Registration Statement will be eligible to receive awards under the Amended Plan. Approximately 252 employees, 5 non-employee directors, and 2 consultants are eligible to receive awards under the Amended Plan. The Amended Plan will be administered by the Board or, to the extent it has delegated its authority under the Amended Plan, the Compensation Committee of the Board (or such other committee of the Board) (the “Plan Administrator”). The Compensation Committee is comprised of “nonemployee directors” for purposes of Rule 16b-3 under the Exchange Act. The Plan Administrator has the power in its discretion to grant awards under the Amended Plan, to designate the eligible participants, to determine the terms and conditions of such awards, to construe and interpret the provisions of the Amended Plan, and to make any other determination and take any other action as it deems necessary or desirable for the administration of the Amended Plan and to protect our interests, among other authority provided under the Amended Plan.

Limitation on Awards and Shares Available

As of October 14, 2026, there were 361,651 shares remaining available for grant under the existing Incentive Plan (assuming achievement of outstanding PSUs at “target” performance goals). As described above, if this Proposal Three is approved, then, as of the Amendment Effective Date, the aggregate number of shares reserved for issuance under the Amended Plan will equal 2,861,651 shares of our Common Stock, all of which may be granted as Incentive Stock Options (“ISOs”) pursuant to Section 422 of the Code. The shares issued under the Amended Plan may be authorized but unissued shares, shares held in treasury or shares purchased in the open market or by private purchase.

As noted above, while we may continue to grant further awards under the existing Incentive Plan prior to the Annual Meeting date, to the extent we do so, the available share reserve under the Amended Plan will be reduced by the number of shares that we grant under the Incentive Plan, if any, between October 14, 2026 and the Annual Meeting date.

To the extent that an award is canceled, forfeited, or terminated without issuance of the full number of shares to which the award related, any shares subject to the award will be available for future grant under the Amended Plan. Additionally, shares withheld in payment of the exercise price or tax-related items with respect to awards will be returned to the Amended Plan for future grants of awards. To the extent an award is paid out in cash rather than shares, such cash payment shall not reduce the number of shares available for issuance under the Amended Plan.

Awards granted under the Amended Plan upon the assumption of, or in substitution for, awards authorized or outstanding under a qualifying equity plan maintained by an entity with which the Company enters into a merger or similar corporate transaction will not reduce the shares authorized for grant under the Amended Plan.

The number of shares that may be issued to any individual under the Amended Plan (when combined with all of our other securities-based arrangements, as applicable) may not exceed 3% of our outstanding number of issued shares from time to time. In addition, under the Amended Plan, the maximum aggregate value of cash compensation and equity-based awards which may be granted to a non-employee director in any fiscal year is $750,000 (calculating the value of any such awards based on the grant-date fair value of such awards for financial-reporting purposes).

Material U.S. Federal Income Tax Consequences

The following is a general summary under current law of the principal United States federal income tax consequences related to awards under the Amended Plan. This summary deals with the general federal income tax principles that apply and is provided only for general information. Some kinds of taxes, such as state, local and foreign income taxes and federal employment taxes, are not discussed. This summary is not intended as tax advice to participants, who should consult their own tax advisors.

Section 409A of the Code

Certain types of awards under the Amended Plan may constitute, or provide for, a deferral of compensation subject to Section 409A of the Code. Unless certain requirements set forth in Section 409A of the Code are complied with, holders of such awards may be taxed earlier than would otherwise be the case (e.g., at the time of vesting instead of the time of payment) and may be subject to an additional 20% penalty tax (and, potentially, certain interest, penalties and additional state taxes). To the extent applicable, the Amended Plan and awards granted under the Amended Plan are intended to be structured and interpreted in a manner intended to either comply with or be exempt from Section 409A of the Code and the Department of Treasury regulations and other interpretive guidance that may be issued under Section 409A of the Code. To the extent determined necessary or appropriate by the Plan Administrator, the Amended Plan and applicable award agreements may be amended to further comply with Section 409A of the Code or to exempt the applicable awards from Section 409A of the Code.

New Plan Benefits

Except for grants of RSUs that will be awarded to each non-employee director serving on our Board in accordance with the non-employee director compensation policy, future awards that our named executive officers, directors, other executive officers and other employees and consultants may receive under the Amended Plan will be determined in the discretion of our Board or Compensation Committee, and neither our Board nor the Compensation Committee has made any determination to make future grants to any persons under the Amended Plan as of the date of this Annual Meeting. Therefore, it is not possible to determine the future benefits that will be received by these participants under the Amended Plan.

Plan Benefits

The table below sets forth summary information concerning the number of shares of our Common Stock subject to equity awards granted to certain persons under the Incentive Plan as of October 14, 2026. The closing per share market value of our stock on October 14, 2026, was $3.06.

Certain awards set forth in this table for the named executive officers were granted in fiscal year 2026 and therefore also are included in the Summary Compensation Table set forth in this Proxy Statement and are not additional awards. Certain awards set forth in this table for the non-employee directors were granted in fiscal year 2026 and therefore also are included in the Compensation of Non-Employee Directors Table set forth in this Proxy Statement and are not additional awards.

Recommendation of Our Board of Directors

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT OUR STOCKHOLDERS VOTE “FOR” THE APPROVAL OF AN AMENDMENT TO THE INCENTIVE PLAN TO INCREASE THE NUMBER OF SHARES OF COMMON STOCK AUTHORIZED FOR ISSUANCE.

PROPOSAL FOUR

TO APPROVE THE ADJOURNMENT OF THE ANNUAL MEETING, IF NECESSARY, TO SOLICIT ADDITIONAL PROXIES IF THERE ARE NOT SUFFICIENT VOTES IN FAVOR OF PROPOSAL THREE

The Proposal

The Board believes that, if the Annual Meeting is convened and a quorum is present, but there are not sufficient votes to approve Proposal Three, it is in the best interests of the Company and its stockholders to enable the Company to continue to seek to obtain a sufficient number of additional votes to approve Proposal Three.

The Company is requesting that our stockholders vote in favor of adjourning the Annual Meeting to another time and place, if necessary, to solicit additional proxies in the event there are not sufficient votes to approve Proposal Three. If our stockholders approve this proposal, we could adjourn the Annual Meeting, and any adjourned or postponed session of the Annual Meeting, to use the additional time to solicit additional proxies, including the solicitation of proxies from our stockholders that have previously voted.

Recommendation of Our Board of Directors

OUR BOARD OF DIRECTORS UNANIMOUSLY RECOMMENDS THAT OUR STOCKHOLDERS VOTE “FOR” THE APPROVAL OF THE ADJOURNMENT OF THE ANNUAL MEETING, IF NECESSARY, TO SOLICIT ADDITIONAL PROXIES IF THERE ARE NOT SUFFICIENT VOTES IN FAVOR OF PROPOSAL THREE.

Your vote is important. Please promptly vote your shares by completing, signing, dating and returning your proxy card or by Internet or telephone voting as described on your proxy card.

APPENDIX A

PROPOSED AMENDMENT TO THE AMENDED AND RESTATED 2022 EQUITY COMPENSATION PLAN

This Amendment (the “Plan Amendment”) to the 5E Advanced Materials, Inc. Equity Compensation Plan (the “Incentive Plan”), is made effective as of the 14th day of October 2026 (the “Amendment Effective Date”), by 5E Advanced Materials, Inc., a Delaware corporation (the “Company”).

“Subject to Section 14 of the Incentive Plan, the maximum number of shares of Common Stock available for issuance pursuant to Awards granted under the Incentive Plan is 3,934,771 (the “Plan Share Reserve”). The Company cannot increase such number without shareholder approval. Notwithstanding anything to the contrary herein, no more than 3,934,771 Shares may be issued pursuant to the exercise of Incentive Stock Options.”

APPENDIX B

Amended and Restated

5E Advanced Materials, Inc.

2022 Equity Compensation Plan

The Board of Directors (the “Board”) of 5E Advanced Materials Inc., a Delaware corporation (the “Company”), has adopted this Amended and Restated 2022 Equity Compensation Plan (the “Plan”) to promote the financial interests of the Company by providing a means by which current and prospective directors, officers, key employees and consultants of the Company can be retained and motivated through acquiring an equity interest in the Company or be paid incentive compensation in the form of the Company’s Common Stock. This Plan constitutes an amendment and restatement of the 2022 Equity Compensation Plan, as amended (the “Original Plan”). This amended and restated Plan will be effective on the Restatement Effective Date. In the event stockholders of the Company do not approve this amended and restated Plan, the Original Plan will continue in full force and effect on its existing terms and conditions.

The Plan provides for the grant of any of the following Awards: