Fox River Resources Corporation — M&A Activity 2026

May 14, 2026

FORM 51-102F3

MATERIAL CHANGE REPORT

Item 1. Name and Address of Company

Fox River Resources Corporation (“Fox River” or the “Company”)
301-141 Adelaide St. West
Toronto, Ontario
M5H 3L5

Item 2. Date of Material Change

May 4, 2026

Item 3. News Release

A news release with respect to the material change referenced in this report was disseminated on May 4, 2026 by the Company, via the newswire services of ACCESS Newswire, a copy of which was subsequently filed under the Company’s profile on SEDAR+ at www.sedarplus.ca.

Item 4. Summary of Material Change

On May 4, 2026, the Company and Avenir Minerals Limited (“Avenir Minerals”) entered into an arrangement agreement (the “Arrangement Agreement”), pursuant to which, subject to the terms and conditions of the Arrangement Agreement, Avenir Minerals agreed to acquire all of the issued and outstanding common shares of Fox River (the “Fox River Shares”) other than the Fox River Shares held by Avenir Minerals and its affiliates, by way of a court-approved plan of arrangement under the Canada Business Corporations Act (the “Plan of Arrangement”) for cash consideration of C$1.10 for each Fox River Share (the “Consideration”) (collectively, the “Transaction”).

Item 5. Full Description of Material Change

5.1 Full Description of Material Change

Overview of the Transaction and the Arrangement Agreement

On May 4, 2026, the Company and Avenir Minerals entered into the Arrangement Agreement, pursuant to which, subject to the terms and conditions of the Arrangement Agreement, Avenir Minerals agreed to acquire all of the issued and outstanding Fox River Shares, other than the Fox River Shares held by Avenir Minerals and its affiliates, by way of the Plan of Arrangement for Consideration of C$1.10 for each Fox River Share payable in cash, for an aggregate purchase price of approximately C$94.3 million on a fully-diluted basis. The Consideration represents a premium of approximately 20% based on the 30-day volume-weighted

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average price of the Fox River Shares on the Canadian Securities Exchange (the "CSE") as of May 1, 2026.

Pursuant to the Arrangement Agreement and the Plan of Arrangement: (a) each outstanding option to purchase Fox River Shares (an "Option") will be deemed to be vested and will be cancelled at the effective time of the Transaction (the "Effective Time") for cash payment equal to the amount, if any, by which the Consideration exceeds the exercise price of such Option, less applicable withholdings; and (b) each outstanding performance share unit of the Company will be deemed to be vested and will be cancelled at the Effective Time for a cash payment equal to the Consideration, less applicable withholdings.

The Transaction is subject to the approval by: (a) at least two-thirds of the votes cast by holders of Fox River Shares ("Fox River Shareholders") and holders of Options (together with Fox River Shareholders, "Fox River Securityholders"), in each case present in person or represented by proxy at the special meeting of Fox River Securityholders to be held to consider and vote upon the Transaction (the "Special Meeting"), voting together as a single class; and (b) a simple majority of the votes cast by Fox River Shareholders present in person or represented by proxy at the Special Meeting, excluding votes cast by certain Fox River Shareholders required to be excluded under Multilateral Instrument 61-101 - Protection of Minority Security Holders in Special Transactions ("MI 61-101") (collectively, the "Required Securityholder Approval"). The Transaction is also subject to other customary closing conditions, including receipt of the approval of the Ontario Superior Court of Justice (Commercial List) and rights of dissent with respect to the Transaction having not been exercised in respect of more than 10% of the outstanding Fox River Shares.

The Transaction constitutes a "business combination" under MI 61-101 because a "related party" (as defined in MI 61-101) of Fox River is entitled to receive a "collateral benefit" (as defined in MI 61-101) as a consequence of the Transaction. The formal valuation requirement under MI 61-101 does not apply to the Transaction because no "interested party" (as defined in MI 61-101) would acquire Fox River or its business as a consequence of the Transaction and no interested party is otherwise party to a "connected transaction" (as defined in MI 61-101) to the Transaction. As described above, Fox River must obtain the requisite "minority approval" (as defined in MI 61-101) for the Transaction under MI 61-101 as part of the Required Securityholder Approval.

The Arrangement Agreement contains customary representations and warranties made by Fox River and Avenir Minerals, and also contains customary covenants, including, among other things, agreement by Fox River to conduct its business in the ordinary course consistent with past practice and to not engage in certain kinds of transactions or take certain actions unless consented to in writing by Avenir Minerals, in each case, during the interim period between the execution of the

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Arrangement Agreement and the earlier of the closing of the Transaction and the termination of the Arrangement Agreement.

The Arrangement Agreement provides for customary deal protection provisions, including non-solicitation covenants that restrict Fox River from, among other things, soliciting Acquisition Proposals (as defined in the Arrangement Agreement), entering into any agreement (other than an Acceptable Confidentiality Agreement (as defined in the Arrangement Agreement)) relating to an Acquisition Proposal or making a Change in Recommendation (as defined in the Arrangement Agreement) in respect of the Transaction, in each case, with limited “fiduciary out” exceptions relating to any Acquisition Proposal that constitutes or could reasonably be expected to constitute or lead to a Superior Proposal (as defined in the Arrangement Agreement), subject to Avenir Minerals’ customary “right to match” any Superior Proposal. If, prior to obtaining the Required Securityholder Approval, Fox River receives an Acquisition Proposal that constitutes a Superior Proposal and certain other conditions are satisfied, the board of directors of the Company (the “Board”) may make a Change in Recommendation and Fox River may enter into a Permitted Acquisition Agreement (as defined in the Arrangement Agreement) with respect to such Superior Proposal. However, in such circumstances, Fox River will be required to hold the Special Meeting in order to put the Transaction to Fox River Securityholders for consideration, and Fox River will not be entitled to terminate the Arrangement Agreement unless the Required Securityholder Approval is not obtained.

The Arrangement Agreement contains certain termination rights in favour of each of Fox River and Avenir Minerals, including, among others, where: (a) the Required Securityholder Approval is not obtained at the Special Meeting; (b) the Effective Time does not occur by August 21, 2026, which date may be postponed for up to a maximum of 90 days in certain circumstances (such date, as may be postponed in accordance with the terms of the Arrangement Agreement, the “Outside Date”); (c) a law or order is enacted that makes closing of the Transaction illegal or that otherwise prohibits or enjoins Fox River or Avenir Minerals from completing the Transaction, and such law has become final and non-appealable, if applicable; or (d) the other party breaches any of its representations or warranties or fails to perform any of its covenants under the Arrangement Agreement in a manner that would cause certain closing conditions to not be satisfied and such breach or failure is incapable of being cured by the Outside Date or is not cured in accordance with the terms of the Arrangement Agreement.

In addition, Avenir Minerals has separate termination rights under the Arrangement Agreement that are exercisable if: (a) prior to obtaining the Required Securityholder Approval, (i) the Board makes a Change in Recommendation, (ii) the Company accepts, approves, endorses or enters into a Permitted Acquisition Agreement or publicly proposes or discloses an intention to do so or (iii) the Company wilfully breaches, or breaches in any material respect, its non-solicitation covenants under the Arrangement Agreement; or (b) a Material Adverse Effect (as defined in the

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Arrangement Agreement) in respect of the Company occurs that is incapable of being cured by the Outside Date.

The Arrangement Agreement provides that a termination fee of C$2.5 million will be payable by the Company to Avenir Minerals upon termination of the Arrangement Agreement in certain circumstances, including if the Arrangement Agreement is terminated by Avenir Minerals prior to obtaining the Required Securityholder Approval as a result of a Change in Recommendation or a material breach of the Company’s non-solicitation covenants.

The Arrangement Agreement also provides that Avenir Minerals will be entitled to an expense reimbursement from the Company up to a maximum amount of C$500,000 upon termination of the Arrangement Agreement by Avenir Minerals if a breach of any representation or warranty or failure to perform any covenant or agreement on the part of the Company under the Arrangement Agreement occurs that would cause any condition relating to the Company’s representations, warranties or covenants not to be satisfied, and such breach or failure is incapable of being cured on or prior to the Outside Date or is not cured in accordance with the Arrangement Agreement, provided that Avenir Minerals is not then in breach of the Arrangement Agreement so as to cause any mutual conditions or any condition relating to Avenir Minerals’ representations, warranties or covenants not to be satisfied.

Fairness Opinion and Voting Recommendation

A special committee (the “Special Committee”) was established to consider and evaluate the Transaction. In connection with its review and consideration of the Transaction, the Special Committee engaged Mills Dunlop Capital Partners Ltd. (“Mills Dunlop”) to act as independent financial advisor to the Special Committee. Mills Dunlop delivered a fairness opinion to the Special Committee stating that, as of the date of the opinion and based upon and subject to the assumptions, limitations, qualifications and other matters set forth in the opinion, the Consideration to be received by Fox River Shareholders (other than Avenir Minerals and its affiliates) under the Transaction is fair, from a financial point of view, to such Fox River Shareholders. Mills Dunlop will receive a fixed fee for its services that is not dependent on completion of the Transaction.

Following consideration of various factors, including receipt of the fairness opinion from Mills Dunlop, and in consultation with its financial and legal advisors, the Special Committee determined that the Transaction is fair and reasonable to Fox River Securityholders and in the best interests of Fox River. Accordingly, the Special Committee (acting through David Lotan, as the sole deliberating and voting member) recommended that the Board: (a) approve the Arrangement Agreement and the Transaction; and (b) recommend that Fox River Securityholders vote in favour of the Transaction.

Following a review of the terms of the Transaction, the recommendation of the Special Committee, and receipt of the fairness opinion from Mills Dunlop, and in consultation with its financial and legal advisors, the Board (acting through David

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Lotan, as the sole deliberating and voting member) determined that the Transaction is fair and reasonable to Fox River Securityholders and in the best interests of Fox River, and resolved to recommend that Fox River Securityholders vote in favour of the Transaction.

Voting Support Agreements

In connection with the Transaction, each of the directors and officers of the Company, who collectively own or exercise control over approximately 23.6% of the issued and outstanding Fox River Shares on a non-diluted basis, have entered into a voting and support agreement (collectively, the “Voting Support Agreements”) with Avenir Minerals, pursuant to which each of them has agreed, among other things, to vote all of their Fox River Shares and Options in favour of the Transaction. In addition, Adrian Day Asset Management (“ADAM”) has entered into a Voting Support Agreement with Avenir Minerals, pursuant to which it has agreed, among other things, to vote or cause to be voted up to approximately 14.7% of the issued and outstanding Fox River Shares in favour of the Transaction. The Voting Support Agreement between ADAM and Avenir Minerals may be terminated if, among other things, a Change in Recommendation occurs.

Other Matters

Avenir Minerals and its affiliates currently own 7.2 million Fox River Shares representing approximately 9.0% of the issued and outstanding Fox River Shares on a non-diluted basis. Avenir Minerals and its affiliates intend to vote each of the Fox River Shares they own in favour of the Transaction.

Subject to the satisfaction or waiver of all conditions to closing set out in the Arrangement Agreement, it is anticipated that the Transaction will be completed early in the third quarter of 2026. Upon closing of the Transaction, it is expected that the Fox River Shares will be delisted from the CSE and that the Company will cease to be a reporting issuer under applicable Canadian securities laws.

Additional Information

The foregoing summaries of the Arrangement Agreement, the Plan of Arrangement and the Voting Support Agreements are not complete and are subject to, and are qualified in their entirety by, the full text of the Arrangement Agreement (including the Plan of Arrangement) and the Voting Support Agreements, copies of which are available under the Company’s profile on SEDAR+ at www.sedarplus.ca. In addition, a copy of the written fairness opinion of Mills Dunlop, and a description of the various factors considered by the Special Committee and the Board in their respective determination to approve the Transaction, as well as other relevant background information, will be included in the Company’s management information circular (the “Circular”) that will be prepared and mailed to Fox River Securityholders in connection with the Special Meeting. Copies of the Circular and certain related documents will be filed with the applicable Canadian securities

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regulators and will be available under the Company’s profile on SEDAR+ at www.sedarplus.ca.

5.2 Disclosure for Restructuring Transactions

Not applicable.

Item 6. Reliance on subsection 7.1(2) of National Instrument 51-102

Not applicable.

Item 7. Omitted Information

Not applicable.

Item 8. Executive Officer

Stephen Case, President and Chief Executive Officer
Tel: (416) 972-9222

Item 9. Date of Report

May 14, 2026

Cautionary Note Regarding Forward-Looking Statements

Certain of the statements and information in this material change report constitute “forward-looking statements” within the meaning of the United States Private Securities Litigation Reform Act of 1995 and “forward-looking information” within the meaning of applicable Canadian provincial securities laws. Forward-looking statements and information can be identified by statements that certain actions, events or results “could”, “may”, “should”, “will” or “would” be taken, occur or achieved. All statements, other than statements of historical fact, are forward-looking statements or information. Forward-looking statements or information in this material change report relate to, among other things: the proposed acquisition by Avenir Minerals of all of the Fox River Shares (other than Fox River Shares held by Avenir Minerals and its affiliates) and the terms thereof; the anticipated filing of materials on SEDAR+; the approval of the Transaction by Fox River Securityholders; regulatory approvals and closing conditions to the Transaction; the expected date of completion of the Transaction; the expectation that the Fox River Shares will be delisted from the CSE and that Fox River will cease to be a reporting issuer under applicable Canadian securities laws and other statements that are not historical facts.

The forward-looking statements and information contained in this material change report reflect Fox River’s current views with respect to future events and are necessarily based upon a number of assumptions that, while considered reasonable by Fox River, are inherently subject to significant operational, business, economic and regulatory uncertainties and contingencies.

Fox River cautions the reader that forward-looking statements and information involve known and unknown risks, uncertainties and other factors that may cause actual results and developments to differ materially from those expressed or implied by such forward-looking statements or

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information contained in this material change report and Fox River has made assumptions and estimates based on or related to many of these factors. In addition, in connection with the forward-looking statements contained in this material change report, Fox River has made certain assumptions, including the ability of the parties to receive, in a timely manner and on satisfactory terms, the necessary court and securityholder approvals; the ability of the parties to satisfy, in a timely manner, the other conditions for the completion of the Transaction, and other expectations and assumptions concerning the Transaction. The anticipated dates indicated may change for a number of reasons, including the necessary securityholder and court approvals, the necessity to extend the time limits for satisfying the other conditions for the completion of the Transaction or the ability of the Board to consider and approve, subject to compliance by Fox River with its obligations under the Arrangement Agreement, a superior proposal for Fox River. Among the key factors that could cause actual results to differ materially from those projected in the forward-looking financial information and statements are the following: the failure of the parties to obtain the necessary securityholder and court approvals or to otherwise satisfy the conditions for the completion of the Transaction; the failure of the parties to obtain such approvals or satisfy such conditions in a timely manner; significant transaction costs or unknown liabilities; the ability of the Board to consider and approve, subject to compliance by Fox River with its obligations under the Arrangement Agreement, a superior proposal for Fox River; the effect of the announcement of the Transaction on the ability of Fox River to retain and hire key personnel and maintain business relationships; the market price of the Fox River Shares and business generally; potential legal proceedings relating to the Transaction and the outcome of any such legal proceeding; the inherent risks, costs and uncertainties associated with transitioning the business successfully; the occurrence of any event, change or other circumstances that could give rise to the termination of the Arrangement Agreement and general economic conditions. Failure to obtain the necessary securityholder and court approvals, or the failure of the parties to otherwise satisfy the conditions for the completion of the Transaction may result in the Transaction not being completed on the proposed terms or at all. In addition, if the Transaction is not completed, and Fox River continues as an independent entity, there are risks that the announcement of the Transaction and the dedication of substantial resources by Fox River to the completion of the Transaction could have an impact on its business and strategic relationships, including with future and prospective employees, customers, suppliers and partners, operating results and activities in general, and could have a material adverse effect on its current and future operations, financial condition and prospects. Additional risks, uncertainties and other factors are identified in Fox River's most recent management's discussion and analysis, which has been filed with the Canadian provincial securities regulatory authorities, as applicable.

Although Fox River has attempted to identify important factors that could cause actual results to differ materially from those set out or implied by the forward-looking statements and information, the foregoing list is not exhaustive and there may be other factors that cause results not to be as anticipated, estimated, described or intended. Investors should use caution when considering, and should not place undue reliance on any, forward-looking statements and information. Forward-looking statements and information are designed to help readers understand Fox River's current views in respect of the Transaction and related matters and may not be appropriate for other purposes. Fox River does not intend, nor does it assume any obligation to update or revise forward-looking statements or information, whether as a result of new information, changes in assumptions, future events or otherwise, except to the extent required by law.

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This material change report does not constitute (and may not be construed to be) a solicitation or offer by Fox River or any of its respective directors, officers, employees, representatives or agents to buy or sell any securities of any person in any jurisdiction, or a solicitation of a proxy of any securityholder of any person in any jurisdiction, in each case, within the meaning of applicable laws.