Mr. Sean Roosen reports

OSISKO DEVELOPMENT ANNOUNCES PROCEEDS OF $24.9 MILLION FROM WARRANT EXERCISE

Osisko Development Corp. has received approximately $24.9-million from the exercise of 5,625,031 common share purchase warrants of the company held by funds advised by Appian Capital Advisory Ltd.

The warrants were originally issued to Appian with an exercise price of $4.43 per common share on July 21, 2025, in connection with the senior secured project loan credit facility totalling $450-million (U.S.) for the development and construction of the company's fully permitted, 100-per-cent-owned Cariboo gold project, located in central British Columbia, Canada.

About Osisko Development Corp.

Osisko Development 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-per-cent-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, 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.