Mr. Daniel Sampieri reports

CAPSTONE COPPER PROVIDES UPDATE ON LABOUR NEGOTIATIONS AT MANTOVERDE OPERATION

Union No. 2, one of the four unions at Capstone Copper Corp.'s Mantoverde mine in Chile, representing approximately 50 per cent of Mantoverde employees, or 22 per cent of the total work force, will take strike action, effective Jan. 2, 2026. Prior to the strike notice, Capstone attempted, in good faith, to reach an agreement for a new collective bargaining agreement with Union No. 2. As a result of the strike, certain activities at the mine will be gradually reduced in a safe manner. During the strike, Capstone expects to continue operations at Mantoverde at a level of up to 30 per cent of normal production.

Capstone Copper remains willing to participate in meetings to reach a resolution, and will continue to adhere to legal procedures, respecting the rights of all its employees, inviting the union to engage in a constructive dialogue and providing the authorities with all requested information. Capstone Copper is committed to the highest standards for integrity and transparency, and looks forward to returning its focus to safe and responsible mining at Mantoverde, which brings great benefits to the work force and surrounding communities.

During 2025, Mantoverde was able to negotiate new three-year collective bargaining agreements with the three other unions.

In 2024, Capstone Copper distributed $682-million in economic value to Chile across its operations, including $136-million in employee wages and benefits. Today, Mantoverde employs approximately 1,270 total employees, including approximately 550 individuals from the local communities in the Atacama region of Chile. The total work force at Mantoverde is approximately 2,940 individuals, including approximately 1,670 contractors.

About Capstone Copper Corp.

Capstone Copper is an Americas-focused copper mining company headquartered in Vancouver, Canada. Capstone's operating portfolio of assets includes the Pinto Valley copper mine located in Arizona, United States, the Cozamin copper-silver mine located in Zacatecas, Mexico, the Mantos Blancos copper-silver mine located in the Antofagasta region, Chile, and the Mantoverde copper-gold mine, located in the Atacama region, Chile. Capstone's growth pipeline includes the fully permitted Santo Domingo copper-iron-gold project, located approximately 35 kilometres northeast of Mantoverde in the Atacama region, Chile, as well as a portfolio of exploration properties in the Americas.

Capstone Copper's strategy is to unlock transformational copper production growth while executing on cost and operational improvements through innovation, optimization, and safe and responsible production throughout its portfolio of assets. The company focuses on profitability and disciplined capital allocation to surface stakeholder value. It is committed to creating a positive impact in the lives of people and local communities while delivering compelling returns to investors by responsibly producing copper to meet the world's growing needs.

We seek Safe Harbor.