Osisko Development Receives Environmental Management Act Permits for Cariboo Gold Project

Press Release

Montreal, Québec, December 12, 2024 – Osisko Development Corp. (NYSE: ODV, TSXV: ODV) (“Osisko Development” or the “Company”) is pleased to announce the granting of the Environmental Management Act permits for its 100%-owned Cariboo Gold Project (“Cariboo” or the “Project”) located in central British Columbia (“BC”), Canada. Together with the BC Mines Act permits secured on November 20, 2024, these approvals mark the successful completion of the permitting process for key approvals, solidifying the Cariboo Gold Project’s shovel-ready status.

“We are very pleased with the receipt of the EMA permits, which, together with the Mines Act permits put the Cariboo Gold project in the enviable position of being construction and operation ready. This significant milestone brings us one step closer to unlocking the project’s value potential for shareholders, Indigenous nations, and stakeholders, while upholding the highest standards in environmental stewardship. With the ongoing bulk sample and underground development work set for completion in Q1 2025, and an optimized feasibility well underway and expected in Q2 2025, the Cariboo Gold project is on track to becoming Canada’s next large-scale gold mine,” commented Sean Roosen, Founder, Chairman and CEO.

“Our government is pleased that this project is one step closer to operation, which will provide good, well-paying jobs and open up long-term opportunities for local small businesses, communities, and First Nations,” said Jagrup Brar, Minister of Mining and Critical Minerals. “We will continue to work with the mining industry to ensure efficient permitting while also guaranteeing the Province’s commitment to environmental protection and reconciliation.”

As previously disclosed, a formal positive final investment decision and the engagement on a project financing package in the coming months would allow for full-scale construction to commence in the second half of 2025 with a targeted completion date at the end of 2027. The Company is advancing discussions, which are active and ongoing, on various funding options, including a comprehensive financing package.

CARIBOO GOLD PROJECT PERMITS

Following a robust and rigorous review process by a dedicated Mine Review Committee, set up by the

Major Mines Office, the Company received the following permits for the Cariboo Gold Project:

• M-247 – Mines Act permit for the Mine Site Complex and Bonanza Ledge;
• M-198 – Mines Act permit for the QR Mill;
• PE-111511 – Environmental Management Act Permit for the Mine Site Complex;
• PE-12601 – Environmental Management Act Permit for QR Mill; and
• PE-17876 – Environmental Management Act Permit for Bonanza Ledge.

The Mines Act permits (received on November 20, 2024) grant the Company the ability to proceed with the construction, operation and reclamation activities on each of the site boundaries, as outlined within the scope of the Project. The Environmental Management Act permits pertain to any Project-related discharge activities to the environment, including water and air, and the framework and limitations thereof, within the areas outside of the immediate mine site boundaries.

Work is ongoing with the Ministry of Water, Land and Resource Stewardship and the Ministry of Forests, which is tracking well, on obtaining all necessary approvals for the construction of the transmission line.

ABOUT OSISKO DEVELOPMENT CORP.

Osisko Development Corp. is a North American gold development company focused on past-producing mining camps located in mining friendly jurisdictions with district scale potential. The Company’s objective is to become an intermediate gold producer by advancing its 100%-owned Cariboo Gold Project, located in central B.C., Canada, the Tintic Project in the historic East Tintic mining district in Utah, U.S.A., and the San Antonio Gold Project in Sonora, Mexico. In addition to considerable brownfield exploration potential of these properties, that benefit from significant historical mining data, existing infrastructure and access to skilled labour, the Company’s project pipeline is complemented by other prospective exploration properties. The Company’s strategy is to develop attractive, long-life, socially and environmentally sustainable mining assets, while minimizing exposure to development risk and growing mineral resources.

For further information, visit our website at www.osiskodev.com or contact:

Sean Roosen		Philip Rabenok
Chairman and CEO		Director, Investor Relations
Email: sroosen@osiskodev.com		Email: prabenok@osiskodev.com
Tel: +1 (514) 940-0685		Tel: +1 (437) 423-3644

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