Osisko Development Reports Fourth Quarter and Year-End 2024 Results

Press Release

Montreal, Québec, Osisko Development Corp. (NYSE: ODV, TSXV: ODV) (“Osisko Development” or the “Company”) reports its financial and operating results for the three and twelve months ended December 31, 2024 (“Q4 2024”).

Q4 2024 HIGHLIGHTS

Operating, Financial and Corporate Updates:

• As of December 31, 2024, the Company had approximately $106.7 million in cash and cash equivalents. Approximately $36.0 million (US$25.0 million) was outstanding as of the end of Q4 2024 under the delayed draw term loan with National Bank of Canada, which matures on October 31, 2025.
• The Company completed a non-brokered private placement of units pursuant to which it issued an aggregate of 19,163,410 units at a price of US$1.80 per unit for gross proceeds of approximately US$34.5 million (the “2024 Non-Brokered Private Placement”). The 2024 Non-Brokered Private Placement was completed in two tranches comprised of the issuance of (i) 13,426,589 units at a price of US$1.80 per unit for gross proceeds of approximately US$24.2 million, which tranche closed on October 1, 2024, and (ii) 5,736,821 units at a price of US$1.80 per unit for gross proceeds of approximately US$10.3 million, which tranche closed on October 11, 2024. Each unit was comprised of one Common Share and one Common Share purchase warrant of the Company entitling the holder thereof to purchase one Common Share at a price of US$3.00 on or prior to October 1, 2029.
• On November 12, 2024, the Company completed a brokered private placement pursuant to which it issued an aggregate of 31,946,366 units at a price of US$1.80 per unit for aggregate gross proceeds of approximately US$57.5 million, including the exercise in full of the option granted to the agents (the “2024 Brokered Private Placement”). Each unit was comprised of one Common Share and one Common Share purchase warrant of the Company entitling the holder thereof to purchase one Common Share at a price of US$3.00 on or prior to October 1, 2029. In connection with the 2024 Brokered Private Placement, the agents were paid a cash commission equal to 4.5% of the aggregate gross proceeds.
• On December 5, 2024, Mr. Stephen Quin was appointed as independent director to the Company’s board of directors and, in connection thereof, was subsequently granted 80,000 deferred share units of the Company on December 19, 2024.
• On December 12, 2024, Ms. Marina Katusa resigned from the Company’s board of directors.

Cariboo Gold Project – British Columbia, Canada (100%-owned)

• Fully Permitted Status. On November 20, 2024, the Company was granted permits pursuant to the Mines Act (British Columbia) for its Cariboo Gold Project. Subsequently, on December 12, 2024, the Company was granted permits pursuant to the Environmental Management Act (British Columbia) for the Cariboo Gold Project. Together with the Mines Act (British Columbia) permits, these approvals mark the successful completion of the permitting process for key approvals, solidifying the Cariboo Gold Project’s shovel-ready status.
  • The Mines Act (British Columbia) permits grant the Company the ability to proceed with the construction, operation and reclamation activities on each of the sites outlined within the scope of the Project. The Environmental Management Act (British Columbia) permits pertain to any project-related discharges to the environment, including water and air, and the framework and limitations thereof, within the areas outside of the immediate mine site boundaries.
  • Work is ongoing with the Ministry of Water, Land and Resource Stewardship and the Ministry of Forests on obtaining all necessary approvals for the construction of the transmission line.
  • On November 7, 2024, the Company announced that, while it had yet to reach an agreement with the Xatśūll First Nation, it remained committed to ongoing engagement and consultation.
• Project Financing. The Company is actively engaged in ongoing discussions on various funding options, including a comprehensive project construction financing package, for the development of the Cariboo Gold Project.
• Pre-Construction Activities. During Q1 2024, under an existing provincial permit, the Company commenced an underground development drift from the existing Cow Portal into the Cariboo Gold Project’s Lowhee Zone to extract a bulk sample of up to 10,000 tonnes of mineralized material.
  • 100% of the underground development has been successfully completed, totalling approximately 1,172 m, to access the target area.
  • The extraction, sampling, assaying, and analysis of mineralized material from the target zone is currently ongoing. Approximately 7,400 tonnes of material has been extracted to date. Lengthy timeframes for receipt of assays and analysis of the results have extended completion of the bulk sampling program into Q2 2025. Once all information is available, a reconciliation process to compare the bulk sample results with the predicted tonnes and grade will be undertaken.

• Optimized Feasibility Study. The Company is in advanced stages of completing an optimized feasibility study (“OFS”) for the Cariboo Gold Project. The OFS will incorporate opportunities to enhance and streamline mine development and the process flowsheet, supporting an accelerated development timeline to reach 4,900 tonnes per day throughput earlier than previously contemplated. It will also reflect updated metal price and foreign exchange assumptions. Additionally, the OFS will integrate updated operating and capital cost estimates, while considering ways to reduce and mitigate any potential capital and operating cost pressures. The OFS base case will remain aligned with the existing permitting framework.

Figure 1: Cariboo Gold Project – Permitting Timeline Summary

Tintic Project – Utah, U.S.A. (100%-owned)

• Phase I Regional Drilling. In 2024, the Company completed two surface diamond drill holes totalling approximately 2,920 m (9,581 ft) at the Big Hill target area testing for copper-gold-molybdenum porphyry mineralization potential. Based on the geological information from these drill holes, the Company identified several high-priority targets for a next phase of the porphyry exploration program.
• Phase II Regional Drilling. As part of the ongoing Phase II regional drilling program initiated in December 2024, the Company is advancing the completion of two drill holes on the Big Hill West and Zuma porphyry targets, expected to be completed in the coming months.

San Antonio Gold Project – Sonora State, Mexico (100%-owned)

• The San Antonio Gold Project remains in care and maintenance.
• The Company is awaiting further guidance from the Mexican government regarding the permitting process and the status of open-pit mining in the country.
• The Company continues to conduct a strategic review of the project and engaged a financial advisor in connection thereof. The strategic review includes, among others, exploring the potential for a financial or strategic partner in the asset or a full or partial sale of the asset.

KEY UPCOMING MILESTONES

*as at December 31, 2024

Notes:

1. The expenditures disclosed in this table include amounts approved by the Board of Directors up until the end of June 2025. Additional expenditures will be required to complete certain of the milestones and are subject to approval by the Board of Directors.

SUBSEQUENT TO Q4 2024

• On January 9, 2025, the Company announced that Mr. David Rouleau was appointed as Vice President, Project Development, and Mr. Éric Tremblay resigned from his position as Chief Operating Officer of the Company.
• On February 3, 2025, the Company released drilling results from its 2024 initial exploration and historic data validation infill drill campaign at its Quesnel River Mine Prospect located within the Company’s wider Cariboo Gold Project.
• On March 26, 2025, the Company appointed Philip Rabenok as Vice President, Investor Relations. Mr. Rabenok joined Osisko Development in November 2022 as Director, Investor Relations.

2024 Year-End Disclosure Documents

The Company’s annual information form (“AIF”) for the year ended December 31, 2024, audited consolidated financial statements (the “Financial Statements”) and related management’s discussion and analysis (“MD&A”) for the three and twelve months ended December 31, 2024 have been filed with Canadian securities regulatory authorities. Osisko Development has also filed its Annual Report Form 40-F consisting of its AIF, Financial Statements and MD&A for the year ended December 31, 2024 with the U.S. Securities and Exchange Commission.

These filings are available on the Company’s website at www.osiskodev.com, on SEDAR+ (www.sedarplus.ca) and on EDGAR (www.sec.gov) under Osisko Development’s issuer profile. Hard copies of these documents will be provided to shareholders of the Company upon written request to the Company’s Investor Relations department, 1100, Av. des Canadiens-de-Montreal, Suite 300, Montreal, Quebec, Canada H3B 2S2 or to ir@osiskodev.com.

Qualified Persons

The scientific and technical information contained in this news release has been reviewed and approved by Daniel Downton, P.Geo., Chief Resource Geologist of Osisko Development, a “qualified person” within the meaning of National Instrument 43-101 – Standards of Disclosure for Mineral Projects (“NI 43-101”).

Technical Reports

Information relating to the Cariboo Gold Project and the current feasibility on the Cariboo Gold Project is supported by the technical report titled “Feasibility Study for the Cariboo Gold Project, District of Well, British Columbia, Canada”, dated January 10, 2023 (amended January 12, 2023) with an effective date of December 30, 2022 (the “Cariboo Technical Report”).

Information relating to the Tintic Project and the current mineral resource estimate for the Trixie deposit (the “2024 Trixie MRE”) is supported by the technical report titled “NI 43-101 Technical Report, Mineral Resource Estimate for the Trixie Deposit, Tintic Project, Utah, United States of America” dated April 25, 2024 (with an effective date of March 14, 2024) (the “Tintic Technical Report”).

Information relating to San Antonio Gold Project is supported by the technical report titled “NI 43-101 Technical Report for the 2022 Mineral Resource Estimate on the San Antonio Project, Sonora, Mexico”, dated July 12, 2022 (with an effective date of June 24, 2022) (the “San Antonio Technical Report”, collectively, with the Tintic Technical Report and the Cariboo Technical Report, the “Technical Reports”).

For readers to fully understand the information in the Technical Reports, reference should be made to the full text of the Technical Reports in their entirety, including all assumptions, qualifications and limitations thereof. The Technical Reports are intended to be read as a whole, and sections should not be read or relied upon out of context. The Technical Reports were prepared in accordance with NI 43-101 and are available electronically on SEDAR+ (www.sedarplus.ca) and on EDGAR (www.sec.gov) under Osisko Development’s issuer profile and on the Company’s website at www.osiskodev.com.

End Notes (excluding tables)

1. In this news release the Company uses certain abbreviations, including: meters (“m”); feet (“ft”).

ABOUT OSISKO DEVELOPMENT CORP.

Osisko Development Corp. is a North American gold development company focused on past-producing mining camps located in mining friendly jurisdictions with district scale potential. The Company’s objective is to become an intermediate gold producer by advancing its flagship fully permitted 100%-owned Cariboo Gold Project, located in central B.C., Canada. Its project pipeline is complemented by the Tintic Project in the historic East Tintic mining district in Utah, U.S.A., and the San Antonio Gold Project in Sonora, Mexico—brownfield properties with significant exploration potential, extensive historical mining data, access to existing infrastructure and skilled labour. The Company’s strategy is to develop attractive, long-life, socially and environmentally responsible mining assets, while minimizing exposure to development risk and growing mineral resources.

For further information, visit our website at www.osiskodev.com or contact:

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