Osisko Development Awards Project and Construction Management Services Contract for the Development of the Cariboo Gold Project

Press Release

MONTREAL, Feb. 09, 2026 Osisko Development Corp. (NYSE: ODV, TSXV: ODV) (“Osisko Development” or the “Company”) is pleased to announce that its wholly-owned subsidiary, Barkerville Gold Mines Ltd., has entered into a definitive Project and Construction Management Services Agreement with JDS Energy & Mining Inc. (“JDS”) for the development of the Cariboo Gold Project, located in British Columbia (the “Cariboo Gold Project”).

Sean Roosen, Chairman and CEO, commented, “Formalizing our partnership with JDS supports an integrated approach to project delivery, as we advance the next phase of work at the Cariboo Gold Project. JDS’ project and construction management experience provides additional capacity and structure across planning and execution, supporting disciplined progress on the development of the Cariboo Gold Project.”

About JDS Energy & Mining Inc.

JDS is a Western Canada-based mining services company founded in 2004 by Jeff Stibbard and comprised of a diverse team of skilled and highly experienced mining and construction professionals. With a proven track record of providing clients with fit-for-purpose solutions and delivering value, JDS has earned a reputation for delivering and executing project plans on budget, on schedule, and most importantly, safely. The JDS team prides itself on delivering projects from concept through operations and ultimately reclamation – an approach it has executed across Canadian and international operations. Past projects include the Minto Mine, the Gahcho Kue Mine, and the Silvertip Mine. Please visit their website at https://jdsmining.ca for more information.

ABOUT OSISKO DEVELOPMENT CORP.

Osisko Development Corp. is a continental North American gold development company focused on past producing mining camps with district scale potential. The Company’s objective is to become an intermediate gold producer through the development of its flagship, fully permitted, 100%-owned Cariboo Gold Project, located in central British Columbia, Canada. Its project pipeline is complemented by the Tintic Project located in the historic East Tintic mining district in Utah, U.S.A., a brownfield property with significant exploration potential, extensive historical mining data, and access to established infrastructure. Osisko Development is focused on developing long-life mining assets in mining-friendly jurisdictions while maintaining a disciplined approach to capital allocation, development risk management, and mineral inventory growth.

For further information, contact:

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