Osisko Development Announces Proceeds of $24.9 Million from Warrant Exercise

ODV NYSE TSXV News Release

www.osiskodev.com Page 1 of 1

OSISKO DEVELOPMENT ANNOUNCES PROCEEDS OF $24.9 MILLION FROM

WARRANT EXERCISE

Montreal, Québec , March 9, 2026 – Osisko Development Corp. (NYSE: ODV, TSXV: ODV)

("Osisko Development" or the " Company") announces that it has received approximately C$24.9

million from the exercise of 5,625,031 common share purchase warrants of the Company (the

"Warrants") held by funds advised by Appian Capital Advisory Limited ("Appian").

The Warrants were originally issued to Appian with an exercise price of C$ 4.43 per common share on

July 21, 2025, in connection with the senior secured project loan credit facility totaling US$450 million

for the development and construction of the Company's fully permitted, 100%-owned Cariboo Gold

Project located in central British Columbia, Canada.

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 si gnificant 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:

Sean Roosen Philip Rabenok

Chairman and CEO Vice President, Investor Relations

Email: [email protected] Email: [email protected]

Tel: +1 (514) 940-0685 Tel: +1 (437) 423-3644

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the

TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this news release. No stock exchange,

securities commission or other regulatory authority has approved or disapproved the information contained herein.