Marimaca Announces Receipt of Environmental Approval for the Marimaca Oxide Deposit 

VANCOUVER, British Columbia, Nov. 11, 2025 (GLOBE NEWSWIRE) -- Marimaca Copper Corp. (“Marimaca Copper” or the “Company”) (TSX:MARI, ASX:MC2) is pleased to announce that its Chilean subsidiary, Marimaca NewCo Limitada (“Marimaca”), has received the formal Resolución de Calificación Ambiental (“RCA”) for its Marimaca Oxide Project (the “MOD” or “Project”), located in the low coastal cordillera of the Antofagasta region of Chile. The RCA represents the formal approval of the Company’s Declaración de Impacto Ambiental (Environmental Impact Statement) (“DIA”) submission made in December 2024 and marks another strategic step closer to being construction-ready at the MOD.

The RCA has been issued following a rigorous preparation and engagement process, including multiple years of baseline environmental studies, social and archaeological information collection, multiple voluntary stakeholder engagement programs and various technical and project engineering studies.

The receipt of the RCA allows Marimaca to advance the next phase of permitting activities for the Project, known as the Sectorial Permits, which are auxiliary permits required for various stages of construction and operation. The Company is already well advanced in its planning for this phase, laying the groundwork for its master execution schedule and positioning the Project to be construction ready in the second half of 2026.

Jose Antonio Merino, Managing Director, Chile and CFO of Marimaca Copper, commented:

“Developing our assets in Chile to the highest possible environmental and social standards is a core objective of Marimaca. We committed significant time and resources to our permitting strategy, to design a project which delivers a strong mitigation strategy for the environmental and social risks identified, a framework for ongoing risk management, while aligning with our corporate ethos to deliver a project which generates long term value for all of our stakeholders. The receipt of the RCA reflects the exceptional work completed, over several years, by our team.

“I would also like to thank our local, regional, and governmental stakeholders for their efficient engagement during the intensive review process, since our formal submission in December 2024. We look forward to a positive ongoing working relationship as we commence the next phase of permitting workstreams required to begin full construction and support our future operations.”

Hayden Locke, President & CEO of Marimaca Copper, commented:

“On behalf of our board and shareholders, I would like to extend our thanks and congratulations to our Chilean team for the significant milestone Marimaca has achieved. They have been the architects and executors of our permitting strategy, which is the culmination of several years of planning and preparation. It has been a challenging week for the Company with the sudden loss of Colin Kinley, a steadfast supporter of the team’s permitting strategy, and we are proud to achieve this milestone as a reflection of his commitment to Marimaca’s success.

“Our team is immensely proud of the Company we are building and holds themselves to high standards when it comes to the responsible development of our projects and our burgeoning reputation as a highly credible custodian for these assets.

“Our focus now shifts to the critical path for Final Investment Decision and Project Sanctioning, for which we have set ourselves the ambitious target of being ready in the second half of 2026.

“Exploration efforts at Pampa Medina continue, and we are increasingly confident in our long-term growth strategy beyond the 50Ktpa of copper production contemplated in our Definitive Feasibility Study. We expect to release a Pampa Medina exploration update to the market in the very near term. There is a sense of real momentum gathering behind us here at Marimaca and we are truly excited for the next stage of development as a Company.”

Contact Information

For further information please visit or contact:

Tavistock

+44 (0) 207 920 3150

Emily Moss / Ruairi Millar

This press release has been authorized for release on the ASX by the Board of Directors of the Company.

Forward-looking Statements

This news release includes certain “forward-looking statements” under applicable Canadian securities legislation, including, without limitation, statements regarding its permitting process and future Sectoral Permits. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by Marimaca, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: risks that Sectoral and Construction Permits are delayed or not received, risks related to share price and market conditions, the inherent risks involved in the mining, exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating costs and expenses, uncertainties related to the necessity of financing, uncertainties relating to regulatory procedure and timing for permitting submissions and reviews, the availability of and costs of financing needed in the future as well as those factors disclosed in the annual information form of the Company dated March 27, 2025 and other filings made by the Company with the Canadian securities regulatory authorities (which may be viewed at ). Readers should not place undue reliance on forward-looking statements. Marimaca undertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.

Neither the TSX nor the Canadian Investment Regulatory Organization accepts responsibility for the adequacy or accuracy of this release.