Capstone Copper Provides Update on Labour Negotiations and Operational Impact at Mantoverde Mine
Capstone Copper Corp. (“Capstone” or the “Company”) (TSX: CS) (ASX: CSC) today provided an update regarding labour negotiations at its Mantoverde Mine in Chile. The Company announced that Union #2, one of the four labour unions operating at Mantoverde, has elected to commence strike action effective January 2, 2026.
Union #2 represents approximately 50% of Mantoverde’s direct employees, which equates to roughly 22% of the mine’s total workforce. Prior to the issuance of the strike notice, Capstone engaged in negotiations with Union #2 in good faith and made sustained efforts to reach agreement on the terms of a new collective bargaining agreement. Despite these efforts, the parties were unable to reach a resolution before the statutory negotiation period concluded.
As a result of the strike action, Capstone has begun to gradually and safely reduce certain operational activities at the Mantoverde Mine. During the strike period, the Company expects to continue operating the mine at reduced levels, with production anticipated to reach up to approximately 30% of normal operating capacity. All operational adjustments are being implemented in accordance with established safety protocols to ensure the well-being of employees, contractors, and surrounding communities.
Capstone reiterated that it remains open and willing to participate in further discussions with Union #2 to reach a mutually acceptable resolution. The Company will continue to comply fully with all applicable legal and regulatory requirements, respect the rights of all employees, and maintain transparent communication with relevant authorities. Capstone has invited Union #2 to re-engage in constructive dialogue and will continue to provide authorities with any information requested throughout the process.
The Company emphasized its ongoing commitment to the highest standards of integrity, transparency, and responsible mining practices. Capstone looks forward to resolving the current labour disruption and returning its full focus to safe, stable, and sustainable operations at Mantoverde—an operation that delivers significant economic and social benefits to employees, local communities, and the broader Atacama region.
Capstone also highlighted its positive labour relations track record at Mantoverde. During 2025, the Company successfully negotiated new three-year collective bargaining agreements with the mine’s three other unions, underscoring its commitment to collaborative and constructive engagement with its workforce.
Mantoverde continues to play a meaningful role in Chile’s economy. In 2024, Capstone Copper distributed approximately $682 million in economic value across its Chilean operations, including $136 million in employee wages and benefits. The Mantoverde Mine currently employs approximately 1,270 direct employees, of whom about 550 are from local communities within the Atacama region. In total, the Mantoverde workforce comprises approximately 2,940 individuals, including roughly 1,670 contractors.
Capstone Copper remains committed to fostering long-term value for its employees, host communities, and stakeholders, and continues to view constructive labour relations as a cornerstone of its sustainable operating strategy.
About Capstone Copper Corp.
Capstone Copper Corp. 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, USA, 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 our portfolio of assets. We focus on profitability and disciplined capital allocation to surface stakeholder value. We are committed to creating a positive impact in the lives of our people and local communities, while delivering compelling returns to investors by responsibly producing copper to meet the world’s growing needs.