Western Copper and Gold Progresses Casino Project with Mitsubishi Materials Share Acquisition and YESAB Supplementary Filings

Mitsubishi Materials Finalizes Non-Dilutive Share Purchase

Mitsubishi Materials Corporation has successfully completed the acquisition of 1.2 million common shares of Western Copper and Gold through open market purchases. This transaction satisfies conditions set forth in the amended and restated investor rights agreement announced on June 15, 2026, increasing Mitsubishi’s ownership stake in Western to approximately 5% on a non-dilutive basis, meaning no new shares were issued.

This acquisition underscores the extension of the investor rights agreement and reinforces the strategic partnership between Mitsubishi Materials and Western. The non-dilutive share purchase reflects confidence from a major global materials company in Western’s strategic direction and the Casino Project’s potential, validating the project’s economics and development trajectory amid ongoing regulatory and permitting efforts.

Submission of Supplementary YESAB Responses Advances Assessment

On July 15, 2026, Western submitted comprehensive responses to supplementary information requests and clarification inquiries from the Executive Committee of the Yukon Environmental and Socio-economic Assessment Board. This submission enhances the technical foundation for YESAB’s formal review of the Casino Project, addressing specific environmental and socio-economic impact questions raised during the assessment.

The Company emphasized that these responses build upon a "substantial body of technical work" supporting YESAB’s evaluation. Following YESAB’s sufficiency determination—a regulatory milestone confirming adequate information has been provided—the Executive Committee is expected to establish a review panel and define its terms of reference. This sufficiency determination is a crucial step in the Yukon assessment process, with investors awaiting YESAB’s next regulatory actions.

Federal Government Names Yukon-B.C. Grid Connect a National Transmission Priority

On June 26, 2026, the Honourable Tim Hodgson, Minister of Energy and Natural Resources, announced the federal government’s prioritization of five transmission projects across Canada, including the Yukon-B.C. Grid Connect. This designation supports infrastructure critical to the Casino Project’s development and aligns with Canada’s National Electricity Strategy, launched by Prime Minister Mark Carney on May 14, 2026, which aims to double the country’s grid capacity by 2050.

The federal priority status directly impacts Western’s project economics and timeline by mitigating uncertainties related to grid infrastructure. The announcement signals government recognition that the transmission project underpins Canada’s long-term energy objectives and resource development in Yukon, strengthening the regulatory and political environment surrounding the Casino Project.

Casino Project Integral to Canada’s Energy Infrastructure Vision

The National Electricity Strategy, unveiled in May 2026, provides a framework within which the Casino Project and its associated infrastructure operate. With a goal to double grid capacity by 2050, the strategy emphasizes renewable and sustainable energy development, aligning with the Casino Project’s role as a major resource development in Yukon.

Western’s leadership views this supportive external environment as validation of the project’s long-term significance for Yukon and Canadian economic growth. President and CEO Sandeep Singh noted that "the backdrop for our project, and our company, continues to strengthen" through strategic partnerships and government backing for energy alternatives in Yukon, positioning the Casino Project as a key component of Canada’s energy transition rather than a standalone mining venture.

Strategic Partnership with Mitsubishi Materials Bolsters Project Progress

Mitsubishi Materials’ ongoing investment in Western through open market share acquisitions signals sustained confidence in the Casino Project and Western’s execution capabilities. As a global diversified materials corporation with extensive copper and mineral resource exposure, Mitsubishi’s share purchases at market prices indicate internal validation of the project’s value and regulatory outlook.

The extension of the investor rights agreement, contingent on Mitsubishi’s share acquisition, formalizes the strategic partnership, granting both parties defined governance and information rights. This structure is typical of significant mining development collaborations and reflects the Casino Project’s long-term nature. Investors may interpret the share acquisition as a positive indicator of momentum in regulatory and technical progress.

Management Highlights Regulatory Progress and Stakeholder Collaboration

Sandeep Singh, President and CEO of Western Copper and Gold, described the Company’s regulatory approach as a careful advancement through the YESAB process, coupled with a commitment to "the highest levels of technical analysis and engagement." This underscores the Casino Project’s alignment with international standards for responsible mining development and ongoing dialogue with Yukon First Nations, local communities, and regulators.

Singh emphasized the convergence of supportive factors: strategic partner confidence from Mitsubishi Materials, government infrastructure backing via Yukon-B.C. Grid Connect federal priority, and recognition of the Casino Project as "a key driver of sustainable, long term, shared benefits in the Yukon and in Canada." This framing situates the project within broader themes of energy security, regional economic growth, and responsible resource stewardship.

Continued Technical and Environmental Assessment Efforts

The July 15, 2026 submission of supplementary YESAB responses reflects Western’s ongoing investment in detailed technical analysis. YESAB’s assessment process requires thorough evaluation of environmental impacts, cumulative effects, socio-economic factors, and mitigation plans. Western’s description of its responses as building on a "substantial body of technical work" indicates extensive baseline studies, impact modeling, and engagement documentation.

Supplementary requests typically arise from YESAB’s detailed technical review. By providing comprehensive responses, Western equips the regulatory body with essential information to complete its assessment and proceed toward panel establishment. The forthcoming sufficiency determination will confirm that the assessment phase has gathered adequate data to support informed decision-making by the panel and authorities.

Commitment to Responsible Mining and First Nations Collaboration

Western emphasizes its dedication to "working collaboratively with First Nations and local communities" and employing "internationally recognized responsible mining technologies and practices." This commitment is crucial for regulatory approval in Yukon, where First Nations governance and consultation are integral to assessment and decision-making. The Casino Project’s location within traditional Yukon First Nations territories makes social license and collaborative relationships foundational to success.

The Company’s focus on responsible mining aligns with growing investor and regulatory emphasis on environmental, social, and governance (ESG) standards. Explicit incorporation of ESG principles into corporate communications reflects Western’s view of ESG performance as central to project economics and regulatory approval, rather than a separate compliance issue. This approach is typical of major greenfield mining projects aiming to differentiate themselves and build enduring stakeholder support.

Regulatory Timeline and Investor Focus Areas

The next key regulatory milestone is YESAB’s sufficiency determination. Upon reaching this decision, the Executive Committee will establish the review panel and define its terms of reference. The timeline for this determination has not been disclosed. Following panel formation, a formal review will be conducted, with recommendations issued to decision-makers within a timeframe set by the terms of reference.

Investors tracking Western will be attentive to announcements regarding YESAB’s sufficiency determination, panel establishment, and disclosure of the panel’s terms and schedule. Additionally, updates on Yukon-B.C. Grid Connect’s development, including regulatory approvals and financing progress, may provide indirect insights into the broader infrastructure environment supporting the Casino Project. Federal and Yukon government communications on resource development policy or energy strategy could also influence the project’s regulatory landscape.