Mr. Hayden Locke reports

MARIMACA ANNOUNCES C$20 MILLION STRATEGIC INVESTMENT FROM MITSUBISHI CORPORATION

Marimaca Copper Corp. will receive a $20-million equity investment by Mitsubishi Corp. by way of non-brokered private placement. Proceeds from the strategic investment will be used to advance and accelerate the development of the company's flagship Marimaca copper project located in the Antofagasta region, Chile.

Mitsubishi will subscribe for an aggregate 4,640,371 units consisting of one common share and one common share purchase warrant at a price of $4.31 per unit. Each warrant will entitle Mitsubishi to purchase one additional common share at an exercise price of $5.60 for a period of 24 months following the closing of the strategic investment. Following completion of the strategic investment, Mitsubishi will own approximately 5.0 per cent of Marimaca's issued and outstanding common shares on a non-diluted basis.

The unit subscription price represents an 11-per-cent premium to the 20-day volume-weighted average price of the company's common shares on the Toronto Stock Exchange as of June 19, 2023.

Mitsubishi is a major investor in the Latin American copper industry with a portfolio of existing investments including Escondida, Los Pelambres, Antamina, Los Bronces and Quellaveco.

Hayden Locke, president and chief executive officer of Marimaca Copper, commented:

"We are pleased to welcome Mitsubishi Corp. as a partner and shareholder in Marimaca. This investment is a strong endorsement of the quality of the Marimaca project from an exceptionally well-respected and established stakeholder in the Chilean copper industry.

"We are pleased that Mitsubishi shares our view that the Marimaca copper project is a unique, very high-quality, development-stage project. Its location affords it several advantages including an expectation that it will be among the lowest carbon intensity copper producers in the industry. It is one of very few new copper projects that has the potential to deliver near-term production of meaningful scale.

"Mitsubishi's investment significantly de-risks our next phase of development and provides funding to accelerate progress toward the definitive feasibility study and permitting, while minimizing dilution to our existing shareholders."

Taro Abe, general manager, base metals department, Mitsubishi Corp., commented:

"We are excited to be involved in the Marimaca project, which has the potential to deliver a meaningful new supply of copper in the near term. Of particular importance to us are the sustainability credentials of the project, which we believe will be a source of very low carbon intensity copper.

"We look forward to working together with the Marimaca team as it moves into the next phase of studies and permitting with the hope we can fully utilize our deep experience in the Chilean copper industry to further enhance this project."

Marimaca intends to use the proceeds of the strategic investment to progress the definitive feasibility study (DFS) and permitting workstreams on the company's Marimaca copper project, and for working capital and general corporate purposes. The strategic investment is expected to close on or before July 11, 2023, and is subject to the approval of the TSX. The securities issued pursuant to the strategic investment will be subject to a statutory four-month hold period in accordance with applicable Canadian securities laws. No finder's fee is payable in connection with the strategic investment.

In connection with the strategic investment, Mitsubishi will be granted certain rights including:

• For so long as Mitsubishi maintains an ownership interest of at least 2.5 per cent, Mitsubishi will be granted participation and top-up rights that enable it to maintain its pro rata ownership interest in the company.
• The right to nominate one member for election to the company's board of directors should Mitsubishi's ownership interest increase to 7.5 per cent or greater.
• The right to appoint two members to an environmental and technical committee that will be formed.

In connection with the strategic investment, Greenstone Resources LP and certain of its affiliates and affiliates of Tembo Capital Mining GP Ltd., including Ndovu Capital XIV BV, have agreed to waive their respective pre-existing rights to participate on a pro rata basis in equity financings by the company.

RBC Capital Markets is acting as financial adviser to the company in connection with the strategic investment.

About Marimaca Copper Corp.

Marimaca Copper is a Canadian exploration and development company focused on developing the Marimaca project, an oxide, open-pit, heap leach copper project located in the Antofagasta region of northern Chile. The company's shares trade on the TSX under the symbol MARI and on the OTCQX under the symbol MARIF.

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