Mr. Sean Roosen reports

OSISKO GOLD COMPLETES US$600 MILLION AGGREGATE PRINCIPAL AMOUNT OF 9.250% SENIOR SECURED NOTES OFFERING

Osisko Gold Group Inc. has completed its previously announced offering of $600-million (U.S.) aggregate principal amount of 9.250 per cent senior secured notes due 2031. The notes will mature on Oct. 1, 2031, and are non-callable for the first two years, and will pay interest semi-annually in arrears on April 1 and Oct. 1 of each year, commencing on April 1, 2027.

The notes offering was completed on a private placement basis to persons reasonably believed to be qualified institutional buyers in accordance with Rule 144A under the United States Securities Act of 1933, as amended, and outside of the United States pursuant to Regulation S under the Securities Act.

Sean Roosen, chairman and chief executive officer, commented: "With construction of the Cariboo gold project under way following our positive final investment decision earlier this month, the completion of this offering further bolsters our already strong balance sheet position and, together with other available sources of capital, fully funds us through commercial production anticipated in 2029. Refinancing the existing Appian project finance facility on cost-effective terms lowers our overall cost of capital and provides greater financial flexibility as we progress construction. The exceptional support from leading institutional investors underscores the quality of the Cariboo gold project, our development strategy and management's ability to deliver. Our focus remains on disciplined project execution while concurrently advancing exploration programs aimed at unlocking the vast exploration potential of the project and its broader regional land package."

The notes are fully and unconditionally guaranteed by certain of the company's subsidiaries, which, at closing, consisted of Barkerville Gold Mines Ltd., its subsidiary that holds the Cariboo gold project in British Columbia, Canada, and are secured by a first priority lien on the company's and each guarantor's property, including equity interests owned by the company and each guarantor in their respective subsidiaries, the interest reserve account and disbursement account described below, and personal and real property, subject to certain exceptions.

The net proceeds from the offering were approximately $578.0-million (U.S.), after deducting the initial purchasers' discounts and commissions and estimated offering expenses. The net proceeds from the offering were used to:

• Repay all amounts outstanding, and terminate all commitments, under the company's senior secured credit facility with Appian Capital Advisory Ltd. with approximately $120.8-million (U.S.) of the net proceeds from the offering;
• Finance a segregated interest reserve account in an amount equal to the first five interest payments on the notes;
• Finance, with the remaining net proceeds, a segregated disbursement account with funds to be used to advance the Cariboo gold project.

Table 1 summarizes the estimated sources and uses of capital from Aug. 1, 2026, through to forecasted commercial production in H2 2029, after giving effect to the net proceeds from the offering.

In connection with the offering, the initial purchasers purchased the notes at a purchase price of 98.25 per cent of the principal amount of the notes.

About Osisko Gold Group Inc.

Osisko Gold Group is a 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, currently under construction in central British Columbia, Canada. The project is situated within the company's broader Cariboo regional land package, which hosts numerous prospective exploration targets and provides opportunities for future discoveries. Its Cariboo project pipeline is complemented by the Tintic project, located in the historic East Tintic mining district in Utah, United States, a brownfield property with significant exploration potential, extensive historical mining data and access to established infrastructure. Osisko Gold 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.

We seek Safe Harbor.