Osisko Development : Q1 2024 Management’s Discussion and Analysis

This MD&A contains certain non-IFRS (as defined herein) measures including, "all-in sustaining cost" (or "AISC") and "cash cost". All-in sustaining cost per gold ounce is defined as production costs less silver sales plus general and administrative, exploration, other expenses and sustaining capital expenditures divided by gold ounces. Cash costs are a non-IFRS measure reported by the Company on an ounces of gold sold basis. Cash costs include mining, processing, refining, general and administration costs and royalties but exclude depreciation, reclamation, income taxes, capital and exploration costs for the life of the mine. Management believes that such measures provide investors with an improved ability to evaluate the performance of the Company. Non-IFRS measures do not have any standardized meaning prescribed under IFRS and, therefore, they may not be comparable to similar measures employed by other companies. The data is intended to provide additional information and should not be considered in isolation or as a substitute for measures of performance prepared in accordance with IFRS, such as Cost of sales.

Cautionary Note Regarding Forward-Looking Statements

Except for the statements of historical fact contained herein, the information presented in this MD&A constitutes "forward- looking information" within the meaning of applicable Canadian Securities Laws concerning the business, operations, plans and financial performance and condition of the Company (collectively, the "Forward-Looking Information"). Often, but not always, Forward-Looking Information can be identified by words such as "plans", "expects", "may", "should", "could", "will", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates", "believes", or variations including negative variations thereof, of such words and phrases that refer to certain actions, events or results that may, could, would, might or will occur or be taken or achieved.

Forward-Looking Information involves known and unknown risks, uncertainties and other factors which may cause the actual plans, results, performance or achievements of the Company to differ materially from any future plans, results, performance or achievements expressed or implied by the Forward-Looking Information. Such factors include, among others: risks relating to capital markets and the availability of future financing on the term acceptable to the Company (or at all); the ability of the Company to meet its financial obligations as they become due; actual operating cash flows, operating costs, free cash flows, mineral resources and reserves and other costs differing materially from those anticipated; changes in project parameters; project infrastructure requirements and anticipated processing methods, exploration expenditures differing materially from those anticipated; actual results of current exploration activities; variations in mineral resources, mineral reserves, mineral production, grades or recovery rates or optimization efforts and sales; failure to obtain, or delays in obtaining, governmental approvals or financing or in the completion of development or construction activities; uninsured risks, including, but not limited to, pollution, cave-ins or hazards for which insurance cannot be obtained; regulatory changes, defects in title; availability or integration of personnel, materials and equipment; risks relating to foreign operations; inability to recruit or retain management and key personnel; performance of facilities, equipment and processes relative to specifications and expectations; unanticipated environmental impacts on operations; market prices; production, construction and technological risks or capital requirements and operating risks associated with the operations or an expansion of the operations, dilution due to future equity financings, fluctuations in gold, silver and other metal prices and currency exchange rates; uncertainty relating to future production and cash resources; inability to successfully complete new development projects, planned expansions or other projects within the timelines anticipated; inability to achieve the business and project milestones as anticipated; adverse changes to market, political and general economic conditions or laws, rules and regulations applicable to the Company; outbreak of diseases and public health crises; the possibility of project cost overruns or unanticipated costs and expenses; accidents, labour disputes, community and stakeholder protests and other risks of the mining industry; failure of plant, equipment or processes to operate as anticipated; risk of an undiscovered defect in title or other adverse claim; factors discussed under the heading "Risk and Uncertainties" in this MD&A and "Risk Factors" in the Company's annual information form for the year ended December 31, 2023; and other risks, including those risks set out in the continuous disclosure documents of the Company, which are available on SEDAR+ (www.sedarplus.ca) and on EDGAR (www.sec.gov) under the issuer profiles of the Company.

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In addition, Forward-Looking Information herein is based on certain assumptions and involves risks related to the business of the Company. Forward-Looking Information contained herein is based on certain assumptions, including, but are not limited to, interest and exchange rates; the price of gold, silver and other metals; competitive conditions in the mining industry; title to mineral properties; financing and funding requirements; general economic, political and market conditions; and changes in laws, rules and regulations applicable to the Company.

Although the Company has attempted to identify important factors that could cause plans, actions, events or results to differ materially from those described in Forward-Looking Information in this MD&A, there may be other factors that cause plans, actions, events or results not to be as anticipated, estimated or intended. There is no assurance that such statements will prove to be accurate as actual plans, results and future events could differ materially from those anticipated in such statements or information. Accordingly, readers should not place undue reliance on Forward-Looking Information in this MD&A. All of the Forward-Looking Information in this MD&A is qualified by these cautionary statements.

Certain Forward-Looking Information and other information contained herein concerning the mining industry and the expectations of the Company concerning the mining industry and the Company are based on estimates prepared by the Company using data from publicly available industry sources as well as from market research and industry analysis and on assumptions based on data and knowledge of this industry which the Company believes to be reasonable. However, although generally indicative of relative market positions, market shares and performance characteristics, this data is inherently imprecise. While the Company is not aware of any misstatement regarding any industry data presented herein, the mining industry involves risks and uncertainties that are subject to change based on various factors.

Readers are cautioned not to place undue reliance on Forward-Looking Information. The Company does not undertake any obligation to update any of the Forward-Looking Information in this MD&A, except as required by law.

Cautionary Note to U.S. Investors Regarding the Use of Mineral Reserve and Mineral Resource Estimates

The Company is subject to the reporting requirements of the applicable Canadian Securities Laws, and as a result reports information regarding mineral properties, mineralization and estimates of mineral reserves and mineral resources in accordance with Canadian reporting requirements, which are governed by National Instrument 43-101 - Standards of Disclosure for Mineral Projects ("NI 43-101"). As such, the information contained in this MD&A concerning mineral properties, mineralization and estimates of mineral reserves and mineral resources is not comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements of the U.S. Securities and Exchange Commission.

1. OUR BUSINESS

Osisko Development is a Canadian-based exploration and development company focused on past-producing properties located in mining friendly jurisdictions with district scale potential. The Company's objective is to become a North American intermediate producer of precious metals, through curating and advancing a portfolio of development projects and investments with potential for value creation. The principal mining assets wholly owned through subsidiaries of the Company as of March 31, 2024, are as follows:

• Cariboo Gold Project (Permitting - British Columbia, Canada) (the "Cariboo Gold Project"), owned and operated by Barkerville Gold Mines Ltd. ("Barkerville").
• Tintic Project (including, the Trixie test mine located within the Company's wider Tintic Project) (Test mining and exploration - Utah, United States) (the "Tintic Project"), owned and operated by Tintic Consolidated Metals LLC ("Tintic").

The Board of Directors of the Company has authorized a strategic review of the San Antonio Project, which includes exploring the potential for a financial or strategic partner in the asset or for a full or partial sale of the asset. The Company has engaged a financial advisor in connection with the strategic review.

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As an exploration and development stage corporation, the Company does not generate sufficient cash flows to advance the evaluation and development of its various projects and properties and has historically relied on equity and debt funding to maintain financial liquidity. Continued adequate financial liquidity is dependent on management's ability to secure additional financings in the future; however, there can be no assurance that the Company will be able to obtain adequate financings in the future, or at terms favourable to the Company (refer to "Liquidity and Capital Resources").

The accompanied unaudited condensed interim consolidated financial statements have been prepared on the basis of accounting principles applicable to a going concern, which contemplates the realization of assets and settlement of liabilities in the normal course of business as they come due. In assessing whether the going concern assumption is appropriate, Management takes into account all available information about the future, which is at least, but not limited to twelve months from the end of the reporting period. The working capital position as at March 31, 2024, will not be sufficient to meet the Company's obligations, commitments and forecasted expenditures up to the period ending March 31, 2025. Management is aware, in making its assessment, of material uncertainties related to events and conditions that may cast a substantial doubt upon the Company's ability to continue as a going concern and accordingly, the appropriateness of the use of accounting principles applicable to a going concern.

2. FINANCIAL AND OPERATING HIGHLIGHTS

The table below provides selected financial information relating to Osisko Development's performance for the three months ended March 31, 2024 and relevant comparable period in 2023:

3. HIGHLIGHTS - Q1 2024

The following summarizes Osisko Development's financial and operational highlights from Q1 2024:

Sustainability & Permitting

There are no environmental issues reported in Q1 2024.

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Three months ended March 31, 2024 and 2023

• In Q1 2024, the Company generated revenues of $1.8 million and incurred an operating loss of $20.5 million compared to $3.5 million and $22.3 million respectively, in Q1 2023. In Q1 2024, the decrease in revenues compared to Q1 2023 is mainly attributable to the decrease of revenue from Bonanza Ledge II and the reduction of sales from the Tintic Project and the San Antonio Project, both projects in care and maintenance during Q1 2024. The lower operating loss in Q1 2024 compared to Q1 2022 is primarily due to the decrease in the level of activities.
• In Q1 2024, the Company incurred a net loss of $8.0 million compared to a net loss of $23.3 million in Q1 2023. The decrease in net loss is primarily due to the reasons noted above offset by a higher fair value gain adjustment of the warrant liability in Q1 2024 compared to Q1 2023.
• The net cash flows used in operating activities in Q1 2024 amounted to $9.1 million compared to $12.8 million in Q1 2023. The decrease is primarily due to the reduction in the general operating activities at the Tintic Project and the San Antonio Project, including the impact on each project's respective working capital.
• Additions to mining interests, property, plant and equipment and exploration and evaluation expenses for Q1 2024 amounted to $10.1 million compared to $23.7 million in Q1 2023. The decrease is primarily due to a reduction in mining development activities including the decrease in exploration spending at the Cariboo Gold Project.
• Net cash inflows from financing activities amounted to $29.1 million in Q1 2024 compared to net cash inflows of $52.1 million in Q1 2023. In Q1 2023, the Company completed a bought deal financing of $51.8 million. In Q1 2024, the Company entered into a credit agreement as described below.

Exploration Activities

• On February 22, 2024, the Company announced the remaining underground drilling and chip sampling results from new development areas as part of its 2023 exploration program at Trixie.
• On March 15, 2024, the Company announced an updated mineral resource estimated for its 100%-owned underground Trixie deposit within the Company's wider Tintic Project. See Section 6.3 Tintic Project - Utah, U.S.A. for additional information.

Management Updates

• On March 1, 2024, Mr. Francois Vézina resigned from his position as Senior Vice President, Project Development, Technical Services and Environment effective as of March 1, 2024 to pursue outside interests.

US$50 Million Credit Facility

• On March 4, 2024, the Company announced that the Company, as guarantor, and Barkerville, its wholly owned subsidiary, as borrower, entered into a credit agreement dated March 1, 2024 with National Bank of Canada, as lender and administrative agent, and National Bank Financial Markets, as mandated lead arranger and sole bookrunner, in connection with a US$50 million delayed draw term loan (the "Credit Facility"). The Credit Facility will be exclusively used to fund ongoing detailed engineering and pre-construction activities at the Cariboo Gold Project. On March 1, 2024, an amount of US$25.0 million ($33.9 million) was drawn under the Credit Facility, net of US$0.7 million ($0.9 million) of fees.

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1. HIGHLIGHTS - SUBSEQUENT TO Q1 2024
2. • On April 26, 2024, the Company announced the filing of a technical report for the updated mineral resource estimate on its 100%-owned underground Trixie deposit within the Company's wider Tintic Project. See Section 6.3 Tintic Project - Utah, U.S.A. for additional information.
3. MANAGEMENT AND BOARD COMPOSITION

The Board of Directors of Osisko Development includes, as elected at the Company's annual meeting of shareholders on May 11, 2023: Sean Roosen (Chair); Charles E. Page (Lead Director); Michele McCarthy; Duncan Middlemiss; Marina Katusa; David Danziger and Éric Tremblay.

Management of Osisko Development includes Sean Roosen (Chair of the Board of Directors and Chief Executive Officer); Chris Lodder (President); Éric Tremblay (interim Chief Operating Officer); Alexander Dann (Chief Financial Officer & Vice President Finance); Laurence Farmer (General Counsel, VP Strategic Development and Corporate Secretary); and Maggie Layman (Vice President, Exploration).

6. EXPLORATION AND EVALUATION / MINING DEVELOPMENT ACTIVITIES

As of the date of this MD&A, the Company's only material properties are the Cariboo Gold Project and the Tintic Project. The following sets out the key milestones, estimated timing and costs in respect of the Company's material mineral projects, based on the Company's reasonable expectations and intended courses of action and current assumptions and judgement, as at March 31, 2024.

*As at March 31, 2024

Notes:

1. The bulk sample expenditures include up until the end of June 2024 and were approved by the Board of Directors.
2. These activities are contributing towards the completion of permitting, which are presently expected to be completed in Q2 2024. Additional costs and time relating to engineering, including water and waste management and electrical and communication, will be required in the construction phase (subject to a positive construction decision and completion of project financing).

Readers are cautioned that the above represents the opinions, assumptions and estimates of management considered reasonable at the date the statements are made and, are inherently subject to a variety of risks and uncertainties and other known and unknown factors that could cause actual events or results to differ materially from those described above. See "Cautionary Note Regarding Forward Looking Statements".

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The Cariboo Gold Project is an advanced stage gold exploration project 100%-owned by the Company located in the historic Wells-Barkerville mining camp, in the District of Wells, central British Columbia, Canada, that extends for approximately 77 kilometres from northwest to southeast. The Company's total land package consists of 415 mineral titles and covers an area of approximately 155,000 hectares. On November 21, 2019, OGR acquired the Cariboo Gold Project through the acquisition of Barkerville. The project was part of the OGR contributed assets that created the Company on November 25, 2020.

Technical reports and mineral resource estimate

The Company completed a Feasibility Study ("FS") for the Cariboo Gold Project with an effective date of January 12, 2023. The scientific and technical information contained in this MD&A relating to the Cariboo Gold Project is supported by the technical report filed in respect of the FS on the Cariboo Gold Project titled "Feasibility Study for the Cariboo Gold Project, District of Well, British Columbia, Canada", dated January 10, 2023 (as amended January 12, 2023) with an effective date of December 30, 2022 (the "Cariboo FS"), which was prepared for the Company by Colin Hardie, P. Eng, Mathieu Bélisle, P. Eng, Katherine Mueller, P. Eng., John Cunning, P. Eng., Paul Gauthier, P. Eng., Aytaç Göksu, P. Eng, Saileshkumar Singh, P. Eng., Éric Lecomte, P. Eng., Vincent-Nadeau Benoit, P. Geo., Carl Pelletier, P. Geo, Jean-François Maillé, P. Eng., Keith Mountjoy, P. Geo., Michelle Liew. P. Eng., David Willms, P. Eng., Timothy Coleman, P. Eng., Thomas Rutkowski., P. Eng., and Laurentius Verburg., P. Geo. Information relating to the Cariboo Gold Project and the Cariboo FS provided herein is qualified in its entirety by the full text of the Cariboo FS, which is available electronically on the Company's website or on SEDAR+ (www.sedarplus.ca) and on EDGAR (www.sec.gov) under the Company's issuer profile, including the assumptions, qualifications and limitations therein.

The Cariboo FS contemplates a staged, lower capital intensity project design with scalable infrastructure to account for the current global inflationary environment. Management believes that this approach to developing the Cariboo Gold Project may mitigate development capital intensity risks while providing an opportunity to maximize margins. The Company anticipates that the potential development of the Cariboo Gold Project may provide a basis for progress towards the establishment of a broader mining district camp, including development of multiple deposits over several trends totaling approximately 80 km of mineralization. A summary of the Cariboo FS results is presented below:

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Notes:

1. Totals may not add up due to rounding.
2. This is a non-IFRS measure. Refer to Non-IFRS Financial Measures.
3. Capital Expenditures do not include sunk costs ($2.5M) nor pre-permit expenses ($64.8M).

Mineral Resources Estimate

The Cariboo FS includes an updated Mineral Resources estimate incorporating an additional 35,578 meters of drilling data from Shaft, Valley, and Lowhee completed since May 24, 2022 being the effective date of the technical report titled "Preliminary Economic Assessment for the Cariboo Gold Project, District of Well, British Columbia, Canada", dated May 24, 2022 for the deposits of Cow Mountain (Cow and Valley Zones), Island Mountain (Shaft and Mosquito Zones), and Barkerville Mountain (Lowhee and KL Zones). This resulted in an increase of 6% of total gold ounces in the Inferred Resources category. Measured and Indicated resources are exclusive of Mineral Reserves. Mineral Resources have an effective date of November 11, 2022.

Table 5: Cariboo Mineral Resources Statement - November 11, 2022

Notes:

1. Mineral Resources are exclusive of Mineral Reserves. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability.
2. The Mineral Resource Estimate conforms to the 2014 CIM Definition Standards on Mineral Resources and Reserves and follows the 2019 CIM Estimation of Mineral Resources and Mineral Reserves Best Practice Guidelines.

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1. A total of 481 vein zones were modelled for the Cow Mountain (Cow and Valley), Island Mountain (Shaft and Mosquito), Barkerville Mountain (BC Vein, KL, and Lowhee) deposits and one gold zone for Bonanza Ledge. A minimum true thickness of 2.0 m was applied, using the Au gold grade of the adjacent material when assayed or a value of zero when not assayed.
2. The estimate is reported for a potential underground scenario at a cut-off grade of 2.0 g/t Au, except for Bonanza Ledge at a cut- off grade of 3.5 g/t Au. The cut-off grade for the Cow, Valley, Shaft, Mosquito, BC Vein, KL, and Lowhee deposits was calculated using a gold price of US$1,700/oz; a USD:CAD exchange rate of 1.27; a global mining cost of $54.32/t; a processing and transport cost of $22.29/t;a G&A plus Environmental cost of $15.31/t; and a sustaining CAPEX cost of $31.19/t. The cut-off grade for the Bonanza Ledge deposit was calculated using a gold price of US$1,700/oz; a USD:CAD exchange rate of 1.27; a global mining cost of $79.13/t; a processing and transport cost of $65.00/t; and a G&A plus Environmental cost of $51.65/t. The cut-off grades should be re-evaluated in light of future prevailing market conditions (metal prices, exchange rate, mining cost, etc.).
3. Bulk density varies from 2.69 g/ cm3 to 3.20 g/ cm3.
4. A four-step capping procedure was applied to composited data. Restricted search ellipsoids ranged from 7 to 50 g/t Au at four different distances ranging from 25 m to 250 m. High-grades at Bonanza Ledge were capped at 70 g/t Au on 2.0 m composited data.
5. The gold Mineral Resources for the Cow, Valley, Shaft, Mosquito, BC Vein, KL, and Lowhee vein zones were estimated using Datamine StudioTM RM 1.9 software using hard boundaries on composited assays. The silver Mineral Resources and the dilution halo gold mineralization were estimated using Datamine StudioTM RM Pro 1.11. The OK method was used. Mineral Resources for Bonanza Ledge were estimated using GEOVIA GEMSTM 6.7 software using hard boundaries on composited assays. The OK method was used to interpolate a block model.
6. Results are presented in situ. Calculations used metric units (meters, tonnes, g/t). Any discrepancies in the totals are due to rounding effects.

Mineral Reserves Estimate

Probable Mineral Reserves of 16.7 Mt grading 3.78 g/t Au for 2.03 Moz of contained gold in underground deposits, as defined below, have an effective date of December 6, 2022 and form the basis of the Cariboo FS. Only Mineral Resources that were classified as Measured and Indicated were given economic attributes in the mine design and when demonstrating economic viability were classified as Mineral Reserves, incorporating an external mining dilution factor of 8% into the Mineral Reserves estimate.

Table 6: Cariboo Mineral Reserves Statement - December 6, 2022

Notes:

1. Totals may not add up due to rounding.
2. Mineral Reserves have been estimated in accordance with CIM Definition Standards for Mineral Resources and Mineral Reserves (2014), which are incorporated by reference in NI 43-101.
3. Mineral Reserves used the following assumptions: US$1,700/oz gold price, USD:CAD exchange rate of 1.27, and variable cut- off value from 1.70 g/t to 4.00 g/t Au

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