MARIMACA COPPER CORP. — Capital/Financing Update 2025

Sep 7, 2025

Appendix 3B - Proposed issue of securities

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Update Summary

Entity name

MARIMACA COPPER CORP.

Announcement Type

Update to previous announcement

Date of this announcement

6/9/2025

Reason for update to a previous announcement

Amendment to number of shares offered to Mitsubishi Corporation (Mitsubishi) in accordance with their equity participation rights (see MC2 prospectus dated 31 March 2025 for further details of the rights) and subject to any necessary TSX approval or shareholder approvals under TSX Listing Rules. Mitsubishi has 30 business days to advise whether they intend to exercise their equity participation rights.

Refer to next page for full details of the announcement

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Appendix 3B - Proposed issue of securities

Part 1 - Entity and announcement details

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1.1 Name of +Entity

MARIMACA COPPER CORP.

We (the entity named above) give ASX the following information about a proposed issue of +securities and, if ASX agrees to +quote any of the +securities (including any rights) on a +deferred settlement basis, we agree to the matters set out in Appendix 3B of the ASX Listing Rules.

If the +securities are being offered under a +disclosure document or +PDS and are intended to be quoted on ASX, we also apply for quotation of all of the +securities that may be issued under the +disclosure document or +PDS on the terms set out in Appendix 2A of the ASX Listing Rules (on the understanding that once the final number of +securities issued under the +disclosure document or +PDS is known, in accordance with Listing Rule 3.10.3C, we will complete and lodge with ASX an Appendix 2A online form notifying ASX of their issue and applying for their quotation).

1.2 Registered Number Type

Registration Number

ARBN 683017094

1.3 ASX issuer code

MC2

1.4 The announcement is

Update/amendment to previous announcement

1.4a Reason for update to a previous announcement

Amendment to number of shares offered to Mitsubishi Corporation (Mitsubishi) in accordance with their equity participation rights (see MC2 prospectus dated 31 March 2025 for further details of the rights) and subject to any

necessary TSX approval or shareholder approvals under TSX Listing Rules. Mitsubishi has 30 business days to advise whether they intend to exercise their equity participation rights.

1.4b Date of previous announcement to this update

5/9/2025

1.5 Date of this announcement

6/9/2025

1.6 The Proposed issue is:

A placement or other type of issue

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Appendix 3B - Proposed issue of securities

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Part 7 - Details of proposed placement or other issue

Part 7A - Conditions

7A.1 Do any external approvals need to be obtained or other conditions satisfied before the placement or other type of issue can proceed on an unconditional basis? Yes 7A.1a Conditions

Approval/Condition Other (please specify in comment section)

Date for determination Is the date estimated or ** Approval actual? received/condition met? 8/9/2025 Estimated No

Comments

Completion of the Placement is subject to certain closing conditions, including but not limited to the receipt of all necessary regulatory and other approvals, including the approval of the Toronto Stock Exchange.

Part 7B - Issue details

Is the proposed security a 'New class' (+securities in a class that is not yet quoted or recorded by ASX) or an 'Existing class' (additional securities in a class that is already quoted or recorded by ASX)? Existing class

Will the proposed issue of this +security include an offer of attaching +securities? No

Details of +securities proposed to be issued

ASX +security code and description

MC2 : CHESS DEPOSITARY INTERESTS 1:1

Number of +securities proposed to be issued

8,247,423

Offer price details

Are the +securities proposed to be issued being issued for a cash consideration? Yes

In what currency is the cash What is the issue price per consideration being paid? +security? AUD - Australian Dollar AUD 9.70000

Will these +securities rank equally in all respects from their issue date with

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Appendix 3B - Proposed issue of securities

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the existing issued +securities in that class? Yes

Is the proposed security a 'New Will the proposed issue of this class' (+securities in a class that is +security include an offer of not yet quoted or recorded by ASX) attaching +securities? or an 'Existing class' (additional No securities in a class that is already quoted or recorded by ASX)? Existing class

Details of +securities proposed to be issued

ASX +security code and description

MC2AA : COMMON SHARES

Number of +securities proposed to be issued

400,000

Reason for the update of 'Number of +securities proposed to be issued'

Offer price details

Are the +securities proposed to be issued being issued for a cash consideration? Yes

In what currency is the cash What is the issue price per consideration being paid? +security? CAD - Canadian Dollar CAD 8.74000

AUD equivalent to issue price amount per +security

9.700000

FX rate (in format AUD 1.00 / primary FX rate (in format AUD rate/primary currency rate): currency rate) Primary Currency rate CAD 0.90100000 AUD 1.00

Will these +securities rank equally in all respects from their issue date with the existing issued +securities in that class? Yes

Part 7C - Timetable

7C.1 Proposed +issue date 12/9/2025

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Appendix 3B - Proposed issue of securities

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Part 7D - Listing Rule requirements

7D.1 Has the entity obtained, or is it obtaining, +security holder approval for the entire issue under listing rule 7.1? No

7D.1b Are any of the +securities proposed to be issued without +security holder approval using the entity's 15% placement capacity under listing rule 7.1? No

7D.1c Are any of the +securities proposed to be issued without +security holder approval using the entity's additional 10% placement capacity under listing rule 7.1A (if applicable)? No

7D.2 Is a party referred to in listing rule 10.11 participating in the proposed issue? No

7D.3 Will any of the +securities to be issued be +restricted securities for the purposes of the listing rules? No

7D.4 Will any of the +securities to be issued be subject to +voluntary escrow? No

Part 7E - Fees and expenses

7E.1 Will there be a lead manager or broker to the proposed issue? Yes

7E.1a Who is the lead manager/broker?

Macquarie Capital (Australia) Limited, Euroz Hartleys Limited, and Beacon Securities Limited

7E.1b What fee, commission or other consideration is payable to them for acting as lead manager/broker?

5% of the proceeds raised

7E.2 Is the proposed issue to be underwritten? No

7E.4 Details of any other material fees or costs to be incurred by the entity in connection with the proposed issue

Part 7F - Further Information

7F.01 The purpose(s) for which the entity is issuing the securities

Detailed design and engineering and project related workstreams at the Marimaca Oxide Deposit, exploration at the Pampa Medina Project and Marimaca sulphide target, and for general corporate purposes.

7F.1 Will the entity be changing its dividend/distribution policy if the proposed issue proceeds? No

7F.2 Any other information the entity wishes to provide about the proposed issue

Up to 400,000 common shares will be offered to Mitsubishi in accordance with their equity participation rights (see the Company¿s prospectus dated 31 March 2025 for further details of the equity participation rights) and subject to any necessary TSX approval or shareholder approvals under the TSX Listing Rules. The exact number of shares to be issued to Mitsubishi is yet to be agreed upon with the Company and Mitsubishi has 30 business days to advise the Company whether they intend to exercise their equity participation rights.

7F.3 Any on-sale of the +securities proposed to be issued within 12 months of their date of issue will comply with the secondary sale provisions in sections 707(3) and 1012C(6) of the Corporations Act by virtue of: The publication of a cleansing notice under section 708A(5), 708AA(2)(f), 1012DA(5) or 1012DAA(2)(f)

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