Osisko Development Announces Supplemental Listing of Warrants

Montreal, Québec, April 14, 2025 – Osisko Development Corp. (NYSE: ODV, TSXV: ODV) (“Osisko Development” or the “Company”) is pleased to announce that its common share purchase warrants (the “Warrants”) issued pursuant to private placements completed by the Company between October and November of 2024 will be listed for trading on the TSX Venture Exchange (the “TSXV”) under the symbol “ODV.WT.V”. The Warrants are expected to be listed for trading on the TSXV effective as of the opening of markets on April 17, 2025.

An aggregate of 51,109,776 Warrants will be listed on the TSXV, which were issued pursuant to (i) a non-brokered private placement of units of the Company that closed in two tranches on October 1, 2024, and October 11, 2024, and (ii) a brokered private placement of units of the Company that closed on November 12, 2024. The Warrants are governed by the terms of a warrant indenture dated October 1, 2024, as amended and supplemented on October 11, 2024, and further amended and supplemented on November 12, 2024, between the Company and TSX Trust Company, as warrant agent (the “Warrant Indenture”).

Each Warrant entitles the holder thereof to purchase one common share of the Company (each, a “Common Share”) at an exercise price of US$3.00 per Common Share on or prior to October 1, 2029. The Warrants will be trading on the TSXV in U.S. dollars.

A copy of the Warrant Indenture is available on SEDAR+ (www.sedarplus.ca) under Osisko Development’s issuer profile.

The Company also anticipates listing the Warrants on the New York Stock Exchange (the “NYSE”) in due course, subject to satisfying certain regulatory conditions and requirements in connection thereof.

This news release does not constitute an offer to sell or a solicitation of an offer to buy any securities of the Company.

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 flagship fully permitted 100%-owned Cariboo Gold Project, located in central B.C., Canada. Its project pipeline is complemented by the Tintic Project in the historic East Tintic mining district in Utah, U.S.A., and the San Antonio Gold Project in Sonora, Mexico—brownfield properties with significant exploration potential, extensive historical mining data, access to existing infrastructure and skilled labour. The Company’s strategy is to develop attractive, long-life, socially and environmentally responsible mining assets, while minimizing exposure to development risk and growing mineral resources.

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

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