Marimaca Copper Corp. (TSX: MARI) (ASX: MC2) is pleased to announce the closing of the previously announced brokered placement in Australia and select other jurisdictions, excluding Canada.

Pursuant to the closing of the Placement, the Company issued 8,247,423 Chess Depositary Interests each at a price of A$9.70 for gross proceeds of approximately A$80,000,000 or approximately C$72,080,000.

Net proceeds from the Placement will be used for exploration at the Pampa Medina Project and Marimaca sulphide target, detailed design and engineering and project related workstreams at the Marimaca Oxide Deposit, and for general corporate purposes.

Euroz Hartleys Limited, Beacon Securities Limited and Macquarie Capital (Australia) Limited, acted as joint lead managers in respect of the Placement. Canaccord Genuity (Australia) limited acted as a co-manager in respect of the Placement. Allotment of the CDIs will occur on September 12, 2025 (AEST). The Placement is subject to the receipt of final approval from the Toronto Stock Exchange (the “TSX”).

This announcement has been prepared for publication in Australia and may not be released to U.S. wire services or distributed in the United States. This news release does not constitute an offer to sell, or the solicitation of an offer to buy, securities in the United States, nor shall there be any sale of these securities in any jurisdiction in which such offer, solicitation or sale would be unlawful. The securities offered in the Placement have not been, and will not be, registered under the U.S. Securities Act of 1933, as amended or any U.S. state securities laws, and may not be offered or sold in the United States or to, or for the account or benefit of, United States persons absent registration or an applicable exemption from the registration requirements of the U.S. Securities Act and applicable U.S. state securities laws.

Related Party Transaction Disclosure

Existing insiders of the Company Assore International Holdings Limited and Ithaki Ltd. participated in the Placement for 1,376,289 CDIs and 1,226,805 CDIs, respectively. Additional information regarding their participation will be disclosed in the material change report to be filed by the Company in accordance with Canadian securities laws.

Other Information

In connection with the Placement, Greenstone Resources L.P. and certain of its affiliates have waived their participation rights. AIH participated directly in the Placement. Mitsubishi Corporation has a participation right to purchase shares pro rata on the same terms as the Placement, exercisable for a period of 30 business days from the closing of the Placement. Mitsubishi’s current ownership, prior to the closing of the Placement, is approximately 4.4% based on public filings.

About Marimaca 

Marimaca is a copper exploration and development company focused on its 100%-owned flagship Marimaca Copper Project and surrounding exploration properties located in Antofagasta Region, Chile.

The Marimaca Copper Project hosts the Marimaca Oxide Deposit, an IOCG-type copper deposit. The Company is currently progressing the Marimaca Copper Project through the Definitive Feasibility Study led by Ausenco Chile Ltda. In parallel, the Company is exploring its extensive land package in the Antofagasta region, including the >15,000ha wholly-owned Sierra de Medina property block, located 25km from the MOD.

This news release is authorized for release by the Board of Directors of Marimaca.

Contact Information

For further information please visit www.marimaca.com or contact:

Tavistock
+44 (0) 207 920 3150
Emily Moss / Ruairi Millar

marimaca@tavistock.co.uk