Osisko Metals (OM) investor relations material

Strategic positioning and leadership

• Positioned as a leading copper development company in Canada with a strong track record of value creation in Quebec mining projects.

• Senior management team has delivered major gold and copper projects, including Canadian Malartic and Windfall, with significant shareholder returns.

• Backed by strategic investors and institutions, which collectively own about 80% of shares outstanding.

Gaspé Copper project highlights

• One of North America's largest undeveloped copper projects, with infrastructure including a deep-sea port, power substation, and paved highway.

• Current in-pit measured and indicated resources total 1.83 billion tonnes at 0.32% CuEq, with 0.24 billion tonnes inferred at 0.46% CuEq.

• Fully funded 50,000-metre drill program in 2026 aims to upgrade resources and test expansion potential.

• Large, long mine life with a low strip ratio of 1.57 and envisioned production of over 140,000 tonnes of copper per year.

• Metallurgical tests indicate high recoveries and clean concentrates; offtake agreement in place with Glencore.

Resource and exploration details

• Updated NI 43-101 mineral resource estimate (base case 0.16% CuEq cut-off): 1.83 Bt M&I at 0.32% CuEq, 0.27% Cu, 0.017% Mo, 1.57 g/t Ag; 0.24 Bt inferred at 0.46% CuEq.

• Historical and ongoing drilling at Porphyry Mountain shows significant intervals, supporting future underground potential.

• 2026 drill program targets resource conversion, expansion at depth and southward, and characterization of high-grade skarn zones.