Creation of Premier Lithium Exploration Company in James Bay Region

Fully-Subscribed C$4.1 Million Financing to Fund First Phase of Lithium Exploration Program

Continued Exposure to and Advancement of Highly Prospective Lithium Exploration Assets Through Equity Ownership Interest in Electric Elements by Osisko Development and O3 Mining

Osisko Development Corp. (NYSE: ODV) (TSX-V: ODV) and O3 Mining Inc. (TSX-V: OIII) (OTCQX: OIIIF) are pleased to announce the successful formation and capitalization of “Electric Elements Mining Corp.” to explore for lithium potential on certain James Bay properties in Eeyou Istchee Area, Nunavik, Québec transferred to Electric Elements by Osisko Development and O3 Mining.

Spin-Out Transaction

Pursuant to the Spin-out Transaction, Electric Elements acquired from:

After giving effect to the Transfer, Osisko Development and O3 Mining held 80% and 20%, respectively, of the outstanding EEM Shares.

The assets transferred to Electric Elements consist of: (i) all of the issued and outstanding shares of Coulon Mines Inc., formerly a wholly-owned subsidiary of Osisko Development; (ii) all of the issued and outstanding common shares of 9852239 Canada Inc., formerly a wholly-owned subsidiary of Osisko Development; (iii) all of the issued and outstanding partnership units in General Partnership Osisko Baie James formerly held by Osisko Development; and (iv) all of O3 Mining’s rights, title and interest in and to the Éléonore Opinaca property, together with any claims, permits, leases, or other forms of tenure substituted, renewed or amended for such interests, and all contractual rights currently held or acquired for the benefit of such property.

Financing

Subsequent to the Transfer, Electric Elements completed an equity financing of 8,217,405 EEM Shares at a price of C$0.50 per EEM Share for aggregate gross proceeds to Electric Elements of C$4,108,702.50. Proceeds of the Financing will be used by Electric Elements to fund the first phase of exploration activities on its newly-acquired James Bay properties and for general corporate purposes.

After giving effect to the Financing, Osisko Development and O3 Mining hold approximately 47% and 12%, respectively, of the outstanding EEM Shares, with the remaining approximately 41% of the outstanding EEM Shares held by the subscribers participating in the Financing.

Completion of the Spin-out Transaction allows Osisko Development and O3 Mining to continue to focus on their respective primary businesses of developing their respective material gold properties, while continuing to have exposure to the Transferred Assets through their respective ownership interests in Electric Elements.

The Financing was completed in reliance on exemptions from the prospectus requirement under National Instrument 45-106 – Prospectus Exemptions, and the EEM Shares sold thereunder are subject to resale restrictions under Canadian securities laws ending four months and one day after the date that Electric Elements becomes a reporting issuer in any province or territory of Canada.

Certain insiders of Osisko Development participated in the Financing for an aggregate of 1,400,000 EEM Shares for total consideration of C$700,000. Each subscription by an insider may be considered to be a “related party transaction” for purposes of Multilateral Instrument 61-101 – Protection of Minority Security Holders in Special Transactions as the Financing may be a transaction whereby Osisko Development is deemed to sell, transfer or dispose of an asset to “related parties” (within the meaning of MI 61-101). The subscriptions by such related parties are exempt from the formal valuation and minority shareholder requirements under MI 61-101 in reliance upon the exemptions contained in section 5.5(a) and 5.7(1)(a), respectively, of MI 61-101 as the fair market value of the transaction, insofar as it involves interested parties, is not more than the 25% of Osisko Development’s market capitalization.

About Osisko Development Corp.

Osisko Development Corp. is a premier North American gold development company focused on high-quality past-producing properties 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.

About O3 Mining Inc.

O3 Mining Inc. is a gold explorer and mine developer on the road to produce from its highly prospective gold camps in Québec, Canada. O3 Mining benefits from the support and expertise of a team of industry leaders as it grows towards being a gold producer with several multi-million-ounce deposits in Québec. O3 Mining is well-capitalized and owns a 100% interest in all its properties (62,000 hectares) in Québec.