Capstone Copper Corp. — Capital/Financing Update 2022

Jun 14, 2022

EXECUTION VERSION

SECOND AMENDMENT TO COMMON TERMS AGREEMENT

June 22, 2021

between MANTOVERDE S.A. as Borrower

MUFG BANK, LTD. as Administrative Agent

BANCO DE CRÉDITO E INVERSIONES

as Onshore Collateral Agent

BNP PARIBAS as Offshore Collateral Agent

Mantoverde S.A.: Common Terms Agreement

This second amending agreement to the Common Terms Agreement is dated June 22, 2021 (this “ Agreement ”), and made between:

MANTOVERDE S.A. , a sociedad anónima , duly incorporated and validly existing under the laws of Chile (the “ Borrower ”);

MUFG BANK, LTD. , as Administrative Agent (acting on behalf of the Majority Senior Lenders) for and on behalf of each of the Finance Parties (in such capacity, together with its successors and permitted assigns, the “ Administrative Agent ”);

BNP PARIBAS , as Offshore Collateral Agent for and on behalf of each of the Finance Parties (the “ Offshore Collateral Agent ”); and

BANCO DE CRÉDITO E INVERSIONES , as Onshore Collateral Agent (in such capacity, together with its successors and permitted assigns, the “ Onshore Collateral Agent ”),

together, the ” Parties ”.

RECITALS

• (A) The Parties and others have entered into the Common Terms Agreement dated February 4, 2021 (as amended on April 16, 2021) between, among others, the Borrower, the Administrative Agent, the Offshore Collateral Agent, the Onshore Collateral Agent, and the other parties and financial institutions party to it from time to time (the “ Common Terms Agreement ”) to set out the terms and conditions common to the Facilities made available for the purpose of the financing of the Project.

• (B) The Senior Lenders have agreed to make available to the Borrower, certain Facilities on, and subject to, the terms and conditions of the Common Terms Agreement, and the other Finance Documents.

• (C) The Permitted Hedging Providers have agreed to execute Hedging Transactions under, and subject to, certain Permitted Hedge Agreements, and terms and conditions of the Common Terms Agreement, and the other Finance Documents.

• (D) The Borrower, the Intercreditor Agent, the Administrative Agent, the Collateral Agent, the Senior Lenders, the Permitted Hedging Providers among others, have entered into a Collateral Agency and Intercreditor Agreement, dated 4 February 2021 (the “ Intercreditor Agreement ”).

• (E) The Borrower requested certain amendments to the Common Terms Agreement, in the form of an amendment request letter dated 12 May 2021 (the “ Request Letter ”). The Required Majority approves the terms of the Request Letter and the amendment requested in it, in accordance with the terms of the Intercreditor Agreement, and on the condition of the execution of this Agreement to formally record the proposed amendments to the Common Terms Agreement.

• (F) Each of the Administrative Agent (acting on the instructions of the Required Majority) and the Offshore Collateral Agent is executing and delivering this Agreement on behalf of each of the Finance Parties pursuant to section 23.4(d) ( Amendment and Waiver ) of the Common Terms Agreement.

In consideration of the mutual promises contained in this Agreement, the adequacy of which are hereby acknowledged by each Party, the Parties HEREBY AGREE AS FOLLOWS:

1.1 Amendments to the Section 1.1 Common Terms Agreement

With effect from the date of this Agreement, the definition of Permitted Asset Disposition in section 1.1 of the Common Terms Agreement shall have been amended and restated as follows:

““ Permitted Asset Disposition ” means, as at any particular time, a sale, transfer or other Disposition of:

• (a) inventory in the ordinary course of business;

• (b) provided the Borrower has complied with all the environmental audits required by Applicable Law prior to such transfer or renouncement, the transfer or renouncement of exploration concessions not included in the description of the Project;

• (c) tangible personal property that is obsolete, or worn out property no longer required in the conduct of the Business;

• (d) Minerals pursuant to this Agreement or otherwise in the ordinary course of business in compliance with the terms of this Agreement;

• (e) any exploration mining concessions that the Borrower determines to be no longer required or desirable in the conduct of the Business;

• (f) other assets and properties of the Borrower, provided that (x) such sale, transfer or other Disposition is permitted by the terms of Section 9.13(b), or (y) the aggregate fair market value of the assets or properties so Disposed do not exceed: (i) with respect to any one transaction or series of transactions, an amount equal to US$5,000,000, and (ii) with respect to all Dispositions of the Borrower in any one Fiscal Year, an aggregate amount equal to US$10,000,000;

• (g) Power Transmission Lines; and

• (h) one or more receivables in respect of any sales of Minerals to any third party in connection with any Permitted Indebtedness as contemplated in paragraph (h) of the definition of Permitted Indebtedness, provided that at any one time the aggregate outstanding amount of receivables so disposed of may not exceed US$30,000,000 (less the aggregate outstanding amount at such time of any other receivables disposed of further to any Permitted Indebtedness as contemplated in paragraph (h) of the definition of Permitted Indebtedness) and for which 100% of the proceeds of such disposal will be received into the Offshore USD Proceeds Account.”

1.2 Amendments to Section 9.3(e) of the Common Terms Agreement

With effect from the date of this Agreement, section 9.3(e) ( Notifications to the Administrative Agent ) of the Common Terms Agreement shall have been amended and restated as follows:

“(e) Until the Final Maturity Date, the Borrower shall:

• (i) promptly notify the Administrative Agent of a suspension of operations of the Project (by the Borrower or any Material Project Party): (A) for a period of more than 15 days during a 30-day period; or (B) which is reasonably likely to result in a suspension of operations of the Project for a period of more than 30 days (excluding any period of scheduled or emergency maintenance), and accompany such notice with an Officer’s Certificate of the Borrower setting forth details of the occurrence referred to therein;

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• (ii) provide access and otherwise allow representatives of the Finance Parties and its advisors to discuss with the Borrower’s senior officers and technical advisors such event;

• (iii) provide the Administrative Agent with such other information with respect to such event or the Borrower’s remedial plans with respect thereto as the Administrative Agent reasonably requests;

• (iv) deliver to the Administrative Agent a certified copy of any Hedge Agreement entered into by the Borrower, in the form agreed in the Hedging Strategy and otherwise in form and substance acceptable to the Administrative Agent (acting reasonably), a certified copy of each confirmation in relation to that Hedge Agreement and, if appropriate a certified copy of an Intercreditor Accession Deed; and

• (v) deliver to the Administrative Agent, notice (with copy to the applicable Offtake Contract counterparty) of the proposed disposal of one or more receivables in respect of sales of Minerals to any third party in connection with any Permitted Indebtedness as contemplated in paragraph (h) of the definition of Permitted Indebtedness in an aggregate outstanding amount of such receivables not exceeding US$30,000,000 (less the aggregate outstanding amount at such time of any other receivables disposed of further to any Permitted Indebtedness as contemplated in paragraph (h) of the definition of Permitted Indebtedness) as permitted under paragraph (h) of the definition of Permitted Asset Disposition, and 100% of the proceeds of which will be received into the Offshore USD Proceeds Account.”

1.3 Representations and Warranties

The Borrower represents and warrants to each Finance Party, on the date of this Agreement as follows:

• (a) upon this Agreement becoming effective, the Repeating Representations of the Borrower will be true, accurate and complete in all material respects by reference to the facts and circumstances then subsisting, to the same extent as though made on and as of this date (or the date this Agreement becomes effective); and

• (b) upon this Agreement becoming effective, no Potential Event of Default or Event of Default has occurred and is continuing, except (as previously disclosed to the legal advisers to the Finance Parties) in respect of the delay in the provision of certain Insurance endorsements in respect of the marine cargo policy and certain Offshore Reinsurance Security Agreements and related notices of assignment in accordance with Section 9.1(i)(i) of the Common Terms Agreement by 17 May 2021, which the Borrower is in the process of procuring during the thirty (30) day cure period which commenced on 18 May 2021 pursuant to Section 11.1(b)(i) of the Common Terms Agreement.

1.4 Interpretation

• (a) Capitalised terms used (but not otherwise defined) in this Agreement and its preamble and recitals have the meaning given to them in the Common Terms Agreement.

• (b) The provisions of sections 1.2 ( Certain Rules of Interpretation ), 1.3 ( Currency ), 1.4 ( Knowledge ), 1.5 ( No Subordination ), and 1.6 ( Conflict ) of the Common Terms Agreement apply to this Agreement as if set forth in this Agreement, mutatis mutandis .

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1.5 Third-Party Rights

• (a) Unless expressly provided to the contrary in a Finance Document, a person who is not a Party has no right under the Third Parties Act to enforce or to enjoy the benefit of any term of this Agreement.

• (b) Subject to section 6.5(a) of the Common Terms Agreement but otherwise notwithstanding any term of any Finance Document, the consent of any person who is not a Party is not required to rescind or vary this Agreement at any time.

1.6 References to and Effect on Other Finance Documents

• (a) Each of the parties to this Agreement agrees that it constitutes a Finance Document for all purposes under the Common Terms Agreement and the other Finance Documents.

• (b) On and after the effectiveness of this Agreement, each reference in the Common Terms Agreement to “this Agreement”, the “Common Terms Agreement”, “hereunder”, “hereof” or words of like import referring to the Common Terms Agreement, and each reference in the other Finance Documents to the “Common Terms Agreement”, “thereunder”, “thereof” or words of like import referring to the Common Terms Agreement, shall mean and be a reference to the Common Terms Agreement, as modified by this Agreement.

• (c) The Common Terms Agreement, as specifically modified by this Agreement, is and shall continue to be in full force and effect and is hereby in all respects ratified and confirmed. Without limiting the generality of the foregoing, the Security Documents and all of the Collateral described in such Security Documents do and shall continue to secure the payment of all Obligations of the Borrower under the Common Terms Agreement, as modified by this Agreement.

• (d) The execution, delivery and effectiveness of this Agreement shall not, except as expressly provided in this Agreement: (i) operate as a waiver of any right, power or remedy of any Senior Lender, Permitted Hedging Provider or any Agent under any of the Finance Documents, nor constitute a waiver of any provision of any of the Finance Documents, (ii) prejudice any other right, power or remedy which the Senior Lenders, the Permitted Hedging Provider or any Agent now have or may have in the future under or in connection with the Common Terms Agreement or the other Finance Documents, or (iii) be a novation (novación) of the obligations of the Borrower under any of the Finance Documents.

1.7 Partial Invalidity

If, at any time, any provision of this Agreement is or becomes illegal, invalid or unenforceable in any respect under any law of any jurisdiction, that will not affect or impair: (i) the legality, validity or enforceability in that jurisdiction of any other provision of the Finance Documents; or (ii) the legality, validity or enforceability in other jurisdictions of that or any other provision of the Finance Documents.

1.8 Notices

The provisions of Section 22.1 ( Notices ) of the Common Terms Agreement shall apply to this Agreement.

1.9 Counterparts

The provisions set out in section 23.13 ( Counterparts ) of the Common Terms Agreement are incorporated by reference in this Agreement as if fully contained in this Agreement.

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1.10 Governing Law and Jurisdiction

This Agreement is governed by English law. The provisions set out in section 23.10 ( Governing Law; Jurisdiction ) of the Common Terms Agreement are incorporated by reference in this Agreement as if fully contained in this Agreement.

1.11 Enforcement

The provisions set out in section 23.11 ( Service of Process ) of the Common Terms Agreement are incorporated by reference in this Agreement as if fully contained in this Agreement.

IN WITNESS WHEREOF this Agreement has been executed by the parties on the date first written above.

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(S) Authorized Signatory

EXECUTED and DELIVERED by ) MUFG Bank, Ltd as Administrative Agent , acting by )

(S) Authorized Signatory

EXECUTED and DELIVERED by ) BNP Paribas as Offshore Collateral Agent , acting by ) )

(S) Authorized Signatory

( Signature page to Second Amending Agreement to Common Terms Agreement )

EXECUTED and DELIVERED by ) BANCO DE CRÉDITO E INVERSIONES as Onshore ) Collateral Agent , acting by ) )

(S) Authorized Signatory

( Signature page to Second Amending Agreement to Common Terms Agreement )