Slide 1: Canada's Leading Copper Development Company
Canada’s Leading Copper Development Company March 2026 TSX: OM | OTCQX: OMZNF | FRA: 0B51
Slide 2: Forward-looking statements and cautionary notes regarding technical information
Forward-looking statements and cautionary notes regarding technical information This presentation (the "Presentation") contains "forward-looking information" within the meaning of applicable Canadian securities legislation. These “forward-looking information” are based on the expectations, estimates
Slide 3: Generating world-class wealth in Quebec
Generating world-class wealth in Quebec > $11 billion in market capitalization value created since 2003 > $100 billion of new wealth creation since 2003 from gold alone…. CANADIAN MALARTIC, QUEBEC WINDFALL, QUEBEC GASPÉ COPPER, QUEBEC 1st Drill Hole Pours 1st Gold Bar Sale for C$4.3Bn Drilling begin
Slide 4: Experienced Canadian mining team with track record of delivering shareholder returns
Experienced Canadian mining team with track record of delivering shareholder returns JOHN BURZYNSKI ROBERT WARES DONALD NJEGOVAN EXECUTIVE CHAIRMAN CHIEF EXECUTIVE OFFICER PRESIDENT CANADIAN MALARTIC: 20M oz Au MARBAN: 3M oz Au WINDFALL: 8M oz Au Canada’s largest Canadian Malartic Quebec’s highest g
Slide 5: Gaspé Copper: one of North America's largest undeveloped copper projects
Gaspé Copper: one of North America’s largest undeveloped copper projects with infrastructure in place Strategic off-take partner GASPÉ COPPER PROJECT Current in-pit resource* 824 Mt Indicated 670 Mt Inferred • 0.27 Cu % • 0.30 Cu % • 0.015 Mo % • 0.020 Mo % • 1.74 g/t Ag • 1.37 g/t Ag • 0.34 Cu Eq %
Slide 6: World class copper assets: Gaspé has the potential to become a world leader
World class copper assets: Gaspé has the potential to become a world leader Copper Resources (Cu Blbs) & Grade (M&I % Cu) 15.00 M&I Resources (Cu Blbs) Inferred Resources (Cu Blbs) M&I Cu Grade (%) 1.40% 1.24% 1.20% 12.50 1.19% 1.00% 10.00 Contained Cu (Blbs) M&I Cu Grade (%) 0.80% 7.50 0.60% 0.59%
Slide 7: Institutions and strategic investors own approximately 80% of the shares outstanding
Institutions and strategic investors own approximately 80% of the shares outstanding TSX: OM | OTCQX: OMZNF | FRA: 0B51 Shares outstanding 727M RESEARCH COVERAGE Shares outstanding (Fully Diluted) 1,058M Canaccord Genuity Peter Bell, Steve Searles Market capitalization C$1.113B Cash (Fully Diluted)
Slide 8: Gaspé Copper today
Gaspé Copper today Porphyry Mtn. Oxide Stockpiles Copper Mtn. Pit Copper Mtn. Former Smelter Location Water Treatment Plant Garages and 2025 Drilling Area Administration Buildings Needle Mtn. Pit TSX: OM | OTCQX: OMZNF | FRA: 0B51 8
Slide 9: Gaspé Copper 2025: completed 118,000 metre drill program
Gaspé Copper 2025: completed 118,000 metre drill program N Completed 118,000-metre drill program with the objective of: • converting existing resources into the indicated and measured resource categories • testing potential expansion of the resources: o to 250 metres below the current resource volum
Slide 10: Gaspé Copper geological cross section
Gaspé Copper geological cross section View looking NE FALL 2024 MRE INDICATED 824 Mt @ 0.34% CuEq SPRING 2024 MRE INFERRED 670 Mt @ 0.39% CuEq C Zone E Zone 2025 Drill program to Porphyry Mtn target: confirm and expand Underground bulk- tonnage potential from the resource 1994 discovery TSX: OM | OT
Slide 11: Gaspé Copper Drill Intercept Highlights February 25, 2026
Gaspé Copper Drill Intercept Highlights February 25, 2026 30-1179 30-1168 30-1167 30-1177 30-0888 (Re-assay) 574.5 m @ 0.37% Cu and 694.0 m @ 0.31% Cu and 816.5 m @ 0.24% Cu and 315.0 m @ 0.42% Cu and 4.13 g/t Ag 92.9 m @ 0.35% Cu and 1.52 g/t Ag 1.26 g/t Ag 1.79 g/t Ag including 51.0 m @ 1.24% Cu a
Slide 12: DPEX re-assay results - DDH 30-0943 February 5, 2026
DPEX re-assay results - DDH 30-0943 February 5, 2026 Needle 3.0 km Mountain Historical Pit GCP - Copper Open Mountain 30-0943 2024Q4 - MRE 852 m @ 0.70% Cu, 2.92 g/t Ag, and 0.062% Mo Resource Block Model Effective Date November 4, 2024 0.12% copper cut-off -200 m 824 Mt 670 Mt Indicated Inferred •
Slide 13: Large, long mine life – Low strip ratio
Large, long mine life – Low strip ratio Positive 2024 metallurgical test Large, long mine life • Modelled base case pit shell measures 700 X 2,000 metres and reaches a maximum depth of approximately 800 metres (2024 MRE) • Low open pit strip ratio of 1.5 (2024 MRE) • Envisioning 160,000 – 200,000 to
Slide 14: A responsible development project focused on sustainable development
A responsible development project focused on sustainable development and respect for host communities Key strategies include: • Implementing comprehensive engagement strategies for local communities, First Nations, and other stakeholders • Government of Québec leading a pilot project designed to max
Slide 15: A six-year timeline to potential mine start-up
A six-year timeline to potential mine start-up 2026 2027-2028 2029-2031 2032 ✓ Completed private placement with strategic investors • Public hearings • Potential start of • Minimum 50,000-metre drill program • Feasibility study (‘27) • Permit issuance production • Start dewatering the historical pit
Slide 16: Osisko Metals: Canada's next leading copper development company
Osisko Metals: Canada’s next leading copper development company Led by a senior multi-disciplinary team with a proven track record of discovery, development, finance, building and operating, and high shareholder returns Strong balance sheet of $200 M (Fully Diluted) with the closing of $32.5M privat
Slide 17: Appendices
Appendices TSX: OM | OTCQX: OMZNF | FRA: 0B51 17
Slide 18: Gaspé Copper acquisition with Glencore Canada
Gaspé Copper acquisition with Glencore Canada Option Terms Price to Pay upon US$25,000,000 through issuance of a convertible note. Exercise of Option The note will be convertible by Glencore into units of Osisko Metals at a price of $0.40 per unit. Each unit will consist of one share and a half-warr
Slide 19: New in-pit indicated resource outlines one of the largest undeveloped Cu-Mo deposits
New in-pit indicated resource outlines one of the largest undeveloped Cu-Mo deposits in North America NI 43-101 Mineral Resource Estimate (base case at 0.12% copper cut-off) Copper Tonnes equivalent Copper Copper Copper Molybdenum Molybdenum Molybdenum Silver Silver Class Mt % % M lbs kt % M lbs Kt
Slide 20: Gaspé Copper 2026 claims boundary
Gaspé Copper 2026 claims boundary N 2026 Gaspé Copper claims boundary Mining concession boundary 2026 active claims boundary TSX: OM | OTCQX: OMZNF | FRA: 0B51 20
Slide 21: Historical Assay Results from Porphyry mountain
Historical Assay Results from Porphyry mountain Large-scale potential for additional mineralization at Gaspé Copper • Deep-seated deposit located below and NE of the 2024 MRE pitshell that remains open at depth • 13 historical drill holes assay results • Future underground bulk-tonnage potential Key
Slide 22: Global Base Metals Comps
Global Base Metals Comps Periodical Global Equity Research 5 February 2 0 26 CG - Base Metal Price Market Enterprise Target Return to 1-Day 1-Week 1-Month 3-Month YTD Ticker Rating P/NAV Projects Commodity Location Analyst Developers 2026/02/04 Capitalization Value Price Target Return Return Return
Slide 23: <100 kilometres from Murdochville to Gaspé, a deep sea port
<100 kilometres from Murdochville to Gaspé, a deep sea port Murdochville Gaspé 97km TSX: OM | OTCQX: OMZNF | FRA: 0B51 23
Slide 24: www.osiskometals.com
www.osiskometals.com TSX: OM | OTCQX: OMZNF | FRA: 0B51 24