Osisko Gold Reports Final Results from its Lowhee Zone Infill Program at the Cariboo Gold Project

Osisko Gold Group Inc. announced final results from a completed 17,072-metre infill drilling program in the Lowhee Zone of the Cariboo Gold Project. Reconciliation at Zone 1 (1260 elevation level) showed approximately 30% more tonnes and approximately 6% more gold ounces, but approximately 18% lower gold grade than the existing short-term model. Zone 2 (1290 elevation level) reconciliation showed approximately 8% fewer tonnes but approximately 8% more gold ounces, with approximately 16% higher gold grade than the short-term model.

Core recovery improved from approximately 92% in 2025 to approximately 94% in 2026. The company anticipates satisfying technical conditions precedent for the remaining undrawn US$350 million senior secured project loan facility in Q3 2026, pending Appian Capital's review. Results validated geological and mine-planning assumptions, supporting continued use of existing assumptions for future infill and indicating potential for resource conversion or upside in unmodelled areas. The Cariboo Gold Project remains a permitted, 100%-owned feasibility-stage project in central British Columbia.

Osisko Development Corp. (ODV) confirmed the successful completion of its Lowhee Zone infill drilling, a key de-risking step that validates the project's mine plan assumptions. The results indicate a grade variance in Zone 1 of -18%, which is offset by a +16% variance in Zone 2, resulting in a net positive tonnage and ounce reconciliation. This outcome is consistent with standard infill drilling behavior and does not materially alter the project's economics.

The update also signals the unlocking of the next US$350 million tranche of the Appian facility, scheduled for Q3 2026. This milestone was already known to the market, which has previously priced in the recent US$300 million convertible notes and the going concern flag.

Osisko Development Corp. is a Canadian mining company focused on advancing its flagship Cariboo Gold Project in central British Columbia. The company 100%-owns the permitted, feasibility-stage Cariboo Gold Project, which is currently focused on the underground development of the Lowhee Zone and regional exploration.

The company also holds the Tintic Project in Utah, USA, where it operates a small-scale heap leach operation. Additionally, Osisko Development Corp. sold its San Antonio Gold Project in Sonora, Mexico, to Axo Copper Corp. in January 2026 in exchange for Axo shares and contingent payments.