Osisko Gold Announces Formal Construction Decision and Development Update for the Cariboo Gold Project
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NEWS RELEASE
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Osisko Gold Announces Formal Construction Decision and
Development Update for the Cariboo Gold Project
(All dollar amounts are expressed in Canadian dollars, unless stated otherwise)
HIGHLIGHTS
• Positive formal construction decision on the Cariboo Gold Project made by the Board of
Directors, with an expected first gold pour in Q1 2029 and commercial production in H2 2029
• US$30 million strategic private placement from an affiliate of Trafigura , concentrate and doré
off-take from Trafigura, and potential prepayment facility of up to US$120 million
• Go-forward capital obligation update for the Cariboo Gold Project of $990 million, supported by
total available and proposed estimated sources of capital of up to $1,637 million, including $837
million in cash & equivalents
• Project completion estimated at 22% as of July 31, 2026; Detailed engineering is approximately
40% complete; Procurement and commitments for long-lead items is progressing with an overall
completion of approximately 44%; $325 million has been committed to date
Toronto, Ontario, September 14, 2026 – Osisko Gold Group Inc. (NYSE: OGG, TSXV: OGG) ("Osisko Gold" or the
"Company") is pleased to announce that its Board of Directors has made a formal positive decision to proceed with
the construction of the Company 's 100% -owned Cariboo Gold Project ( "Cariboo" or the "Project"), located in
central British Columbia, Canada.
Sean Roosen, Chairman and CE O, commented: "The Board 's formal positive decision to commence full -scale
construction of our flagship Cariboo Gold Project represents a defining milestone for Osisko Gold and a pivotal
inflection point toward our objective of becoming an intermediate gold producer . This decision is a culmination of
more than a decade of de-risking work on the Project , from early exploration when the first drill s hit the ground in
2015, through permitting and technical studies, and into project financing and pre-construction. It reflects our
confidence in the significant long-term value Cariboo can deliver to our shareholders and other stakeholders, and in
the transformational impact it can have on the future of Osisko Gold. I'd like to commend our talented team for their
professionalism, dedication and extensive contributions over the years that have brought us to this important
milestone."
"With this step forward, supported by our strong balance sheet position and other sources of available and proposed
funding, our focus is now firmly on disciplined project execution toward first gold in early 2029. Based on an estimated
remaining go-forward capital obligation of C$990 million and spot gold prices of US$ 4,350/oz, the Project
demonstrates robust economics with after-tax NPV5% of C$ 3.2 billion, after-tax IRR of 42.7%, and average annual
free cash flow of C$642 million in the first 5 years, underscoring its significant leverage to the gold price. Construction
is expected to support 613 direct jobs at its peak, followed by 525 permanent jobs during operations, while generating
substantial direct and indirect economic benefits for local communities and the Province of British Columbia. Bringing
Cariboo through construction and into production represents only the first step in establishing a strong platform for
the Company's long-term growth strategy. In parallel, we continue to accelerate ongoing conversion drilling within
the current deposit and advance exploration of the substantial potential at depth and along strike within the existing
permit footprint, as well as across the broader Cariboo regional property. We look forward to providing further regular
updates on our progress."
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Project Go-Forward Capital Obligation Estimate Update
The Project's remaining go-forward capital obligation is estimated at $990 million, net of approximately $272 million
in costs incurred up to and including July 31, 2026, inclusive of contingency of approximately 16.5%, and assuming
the leasing of major mining equipment of approximately $ 117 million. Relative to the initial cost estimate outlined
in the 2025 Optimized Feasibility Study (as defined herein), the go -forward update reflects costs incurred to date,
progress achieved on detailed engineering and the procurement of major contracts, updates to certain cost
assumptions to account for market inflation due to passage of time and broader industry and labour trends,
inclusion of costs related to a PCM contract, and the reclassification of certain expenditures previously included in
operating costs, principally those associated with the construction of the transmission line. The update also reflects
certain modifications to the construction schedule, resulting in an anticipated 30 -month construction period from
August 1, 2026 (from 24 months in the 2025 FS) to first gold pour in Q1 2029 and 36 months (from 34 months in
the 2025 FS) to commercial production in H2 2029.
Table 1: Go-forward Capital Obligation Estimate Update – Summary1,6
Items Go-forward Capital Obligation
(C$ mm)
Go-forward Capital Obligation
(US$ mm)2
Underground mine & development3 $390 $283
Water and waste management $124 $90
Power and electrical $98 $71
Surface infrastructure $47 $34
Process plant – Mine Site Complex $213 $154
Construction indirects $215 $156
Contingency (16.5%) $82 $59
Capital Costs $1,169 $847
Pre-production net revenue4 ($231) ($167)
Pre-production capitalized operating costs4 $169 $122
Equipment financing5 ($117) ($85)
Go-forward Capital Obligation Update $990 $717
1. From August 1, 2026.
2. Assuming a USD:CAD exchange rate of C$1.38 per US$1.00.
3. Underground mine and development costs already include an embedded contingency.
4. The pre-production period is defined as the period prior to the achievement of a minimum of 30 consecutive days of operations during which the mill operates at
an average of at least 60% of nameplate throughput of 4,900 tpd. During this ramp-up phase operating costs are capitalized and netted against revenues.
5. Equipment lease financing includes certain assumptions on mining and other equipment contemplated under currently negotiated, non -binding term sheets, and
remain subject to change as negotiations progress. The equipment leasing market remains robust, and the Company continues to evaluate opportunities that
would enhance its financial flexibility throughout the construction period and thereafter.
6. Totals may not add up due to rounding.
7. In connection with the go-forward capital obligation update, the Company will undertake a normal course review of its non -financial assets relating to the
Cariboo Gold Project in accordance with IFRS Accounting Standards as at September 30, 2026, as part of its third quarter 2026 financial results preparation. For
the avoidance of doubt, any impairment charge, if any, would be non -cash in nature and would have no impact on the Company 's cash flows.
The estimated go-forward capital obligation is expected to be expended over the construction period set out below,
based on an assumed USD:CAD exchange rate of C$1.38 per US$1.00 . To mitigate financial exposures associated
with the go -forward capital obligation, including currency and commodity risks, and to protect future operating
cash flows, the Company may opportunistically contemplate entering into derivative contracts, such as put options.
Table 2: Go-forward Capital Obligation – Estimated Timing of Spend (% of total)1,2
20263 2027 2028 2029
10% 40% 35% 15%
1. Assuming a USD:CAD exchange rate of C$1.38 per US$1.00.
2. Capital spend percentage breakdown associated with capital cost items only, and excludes capitalized revenue in year 2029.
3. Partial year from August 1, 2026, onwards.
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The Project is designed as a conventional, decline-accessed underground mining operation employing mechanized
long-hole stoping mining methods , with paste backfill, to extract ore from gold -bearing vein corridors .
Underground access is currently provided through the Cow portal, with development extending into the Lowhee
and Cow deposit Zones. At the mine site complex, earthworks have commenced on the second underground access
at the Valley Portal. Once established, the Valley Portal will provide a second development front and support critical
path primary development access to the Valley and Sh aft Zones, which host the majority of the Cariboo Gold
deposit's mineral reserves and mineral resources.
Approximately 3.0 kilometres of underground development has been completed to date. Early works have already
commenced during pre-construction, with preparatory activities advancing at the mine site complex, waste rock
storage facility, sediment control pond and water treatment plant , among other areas. Major earthworks are
scheduled to ramp -up in Q3 2026 and are expected to continue through Q4 2027 , with the process plant
foundations work commencing in the summer of 2027 and building enclosure targeted for Q2 2028 . The expected
timeline to commercial production, including key milestones and work areas, is outlined in Figure 1 below:
FIGURE 1: Cariboo Gold Project Development Timeline to Commercial Production
Trafigura Financing and Commercial Agreements
As part of the Board’s decision to approve a final investment decision ("FID"), the Company is pleased to announce
that it and its wholly -owned subsidiary, Barkerville Gold Mines Ltd. (" Barkerville"), have entered into agreements
(the "Trafigura Financing and Commercial Agreements") with Trafigura Canada Limited ("Trafigura") and Urion
Investments Holdings Limited ("Urion"), an affiliate of Trafigura, that support the development of the Project.
The Trafigura Financing and Commercial Agreements comprises: (i) a subscription agreement between the
Company and Urion pursuant to which Urion has agreed to acquire 9,554,141 common shares of the Company
(each, a "Common Share ") at a price of US$ 3.14 per Common Share (the " Issue Price "), representing a 10%
premium to the five-day volume weighted average price of the Common Shares on the TSX Venture Exchange prior
to signing, for gross proceeds of approximately US$30 million (the "Equity Investment"); (ii) offtake agreements
between Barkerville and Trafigura for 100% of the (x) gold concentrate for the first four years of production at the
Cariboo Gold Project (or until 80,000 dry metric tons of concentrate are delivered) and (y) gold doré for the first
four years of production (together, the "Offtake Agreements"); and (iii) non-binding terms and an exclusivity period
in respect of a potential subordinated gold prepayment facility and a further six -years of concentrate and doré
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offtake between Barkerville and Trafigura (the "Prepay Facility "). The proposed Prepay Facility, as currently
contemplated, doesn't provide for any financial maintenance covenants, with final terms remaining subject to the
execution of a definitive agreement.
Sean Roosen further commented: “We are very pleased to welcome Trafigura, a global leader in the commodities
industry, as a long -term strategic partner at Cariboo . Its strategic investment in the Company reflects confidence in
both the Project and our team's ability to execute on its construction. We look forward to advancing towards a definitive
agreement on the prepay financing, which would provide a significant additional non-dilutive source of capital for the
construction of Cariboo.”
The proceeds of the Equity Investment will be used for the development of the Cariboo Gold Project. The Common
Shares to be issued under the Equity Investment will be subject to a statutory hold period of four months and one
day from the date of issuance pursuant to applicable Canadian securities laws. Closing of the Equity Investment
remains subject to final acceptance of the TSX Venture Exchange and the New York Stock Exchange.
In connection with the Equity Investment, Urion has also agreed to enter into a voting support agreement with the
Company (the "Voting Support Agreement "), pursuant to which Urion will agree to vote its Common Shares in
accordance with the recommendations of the board of directors or management of the Company, subject to certain
exceptions. The Voting Support Agreement also contains customary standstill an d lock-up provisions restricting
Urion's ability to acquire additional Common Shares or dispose of its Common Shares for specified periods.
The Offtake Agreements provide for the purchase by Trafigura of 100% of the gold concentrate and doré bars
produced by Barkerville from the Cariboo Gold Project at prices that incorporate prevailing London Bullion Market
Association and deductions including standard treatment and refining charges. Deliveries under the Offtake
Agreements are expected to commence upon the start of first gold pour at the Cariboo Gold Project.
Barkerville and Trafigura have also agreed to non -binding terms in respect of a potential Prepay Facility of up to
US$120 million and Trafigura has been granted an exclusivity period during which the parties will negotiate
definitive documentation for such facility. There is no assurance that definitive documentation for the Prepay Facility
will be entered into on the terms currently contemplated or at all. The non-binding terms contemplate that the
Prepay Facility will be secured by a subordinated security interest against the assets of Barkerville. The facility is
contemplated to be available to draw for three years from closing, with a maturity date that is at a minimum five
years from closing at an interest rate of SOFR plus 6.00%.
Double Zero Capital LP ( "Double Zero"), an existing insider of the Company, has pre -emptive rights under the
investor rights agreement dated August 15, 2025, between Double Zero and the Company (the "Double Zero IRA")
to participate in the Equity Investment on the same terms as Urion, subject to the terms and conditions of the
Double Zero IRA. Double Zero is entitled to participate in the Equity Investment on the same terms as Urion in order
to maintain its existing ownership percentage in the Company. As of the date hereof, Double Zero has not waived
its pre-emptive rights under the Double Zero IRA.
Closing of the Equity Investment is expected to occur in September 2026, subject to the satisfaction of customary
closing conditions, including final acceptance of the TSX Venture Exchange and the New York Stock Exchange. The
Equity Investment is not subject to any minimum subscription amount.
Sources and Uses of Capital
The Company intends to maintain a disciplined approach to capital allocation over the ensuing construction period,
focused on preserving sufficient liquidity and financial flexibility through the Project's construction, ramp-up and
achievement of commercial production. The Company also intends to continue its infill and conversion drilling
programs throughout the construction phase to further de -risk planned production areas by : (a) increasing
geological confidence and definition of the existing measured and indicated mineral resources , and (b) supporting
the upgrade of inferred mineral resources to higher confidence categories and, where appropriate, their potential
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conversion of such resources to mineral reserves after considering applicable modifying factors.
Table 3 summarizes the estimated sources and uses of capital from August 1, 2026 through to forecasted
commercial production in H2 2029. Total sources of capital are estimated at approximately $1,637 million (US$1,186
million) and comprise current cash and cash equivalents, marketable securities, and project debt, and are subject to
the successful closing of the Equity Investment, the execution of the related definitive agreement in connection with
the gold prepay facility, and certain assumptions in relation to equipment financing. Estimated uses of capital are
estimated at approximat ely $1,435 million (US$1,040 million) and include the remaining go -forward capital
obligation, working capital, exploration expenditures, debt service and financing costs, and other general corporate
expenditures. This results in projected surplus liquidity of approximately $201 million (US$146 million).
TABLE 3: Sources and Uses of Capital (from August 1, 2026 to commercial production)
1. Adjusted working capital is as of June 30, 2026, and includes cash and cash equivalents of approximately $837 million, net of current liabilities.
2. Exploration expenditures include remaining flow-through expenditure obligations of approximately $22 million, with the balance related to planned exploration
activities across conversion, infill, and CGP deeps exploration surface and underground drilling.
Additional potential sources not reflected in the estimated sources above include proceeds, if any, from the exercise
of certain outstanding warrants of the Company. Full exercise of such warrants would generate potential proceeds
of approximately US$120 million from the warrants expiring in August 2027 with an exercise price of US$2.56 per
Common Share, which are subject to an acceleration provision beginning in mid -November 2026 , and
approximately US$150 million from warrants expiring in October 2029 with a n exercise price of US$3.00 per
Common Share. The Company continues to actively evaluate opportunities to optimize its project debt structure
and reduce its overall cost of capital. The exercise of Company warrants is entirely at the discretion of the holders
thereof, and there can be no assurance that any or all of the Company w arrants will be exercised or that the
Company will receive any proceeds therefrom.
Summary of Project Metrics
In connection with the Project's go-forward capital obligation update, the Company has adjusted, where applicable,
certain financial inputs in the Cariboo Technical Report (as defined herein) to reflect the Project's current status and
the prevailing commodity price environment , which have an impact on project economics . As noted above, t he
update also reflects certain modifications to the construction schedule, resulting in an anticipated 30 -month
construction period from August 1, 2026 (from 24 months in the 2025 FS) to first gold pour in Q1 2029 and 36
months (from 34 months in the 2025 FS) to commercial production in H2 2029.
Except for these adjustments, the information contained in the Cariboo Technical Report (as defined herein) relating
to geology and mineralization, mineral reserves and mineral resources, mining method s and mineral processing,
together with all other material assumptions and qualifications, remains current and unchanged. A summary of
Project metrics is presented in Table 4:
Sources of Capital C$ mm US$ mm Uses of Capital C$ mm US$ mm
Adjusted working capital $817 $592 Go-forward Capital Obligation $990 $717
Marketable securities (equity book) $74 $53 Corporate G&A $60 $43
Project Debt, net $483 $350 Exploration Expenditures $164 $119
Equipment Leasing, net basis $56 $40 Debt service, financing, other, net $221 $160
Trafigura Equity Investment $41 $30
Offtake Prepay Facility $166 $120
Total Sources $1,637 $1,186 Total Uses $1,435 $1,040
SURPLUS $201 $146
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Table 4: Cariboo Gold Project – Summary of Project Metrics1
Metric units Feasibility Study
(April 2025)
Go-Forward Update
(August 2026)
Mine life years 10 10
Annual throughput tpd 4,900 4,900
Average gold head grade g/t Au 3.62 3.62
Total payable gold, LOM koz Au 1,894 1,894
Avg. gold production, LOM / First 5 years koz/yr 190 / 202 190 / 202
Gold price US$/oz $2,400 $3,570 (LT consensus) $4,350 (spot)
Exchange rate USDCAD 1.35 1.38 1.38
Total cash costs2 US$/oz $947 $957 $996
All-in sustaining costs2 US$/oz $1,157 $1,163 $1,202
Project Go-Forward Capital Obligation3
Initial capital $ mm $881 $990 $9394
Sustaining capital $ mm $426 $426 $426
Economic Results (after-tax)
Total free cash flow, LOM $ mm $1,577 $3,610 $4,828
Net present value (NPV5%) $ mm $943 $2,323 $3,181
Internal rate of return (IRR) % 22.1% 34.7% 42.7%
Payback, from commercial production years 2.8 2.2 1.8
Average free cash flow2, LOM / first 5 years $ mm $158 / $296 $362 / $5215 $485 / $6425
1. Totals may not add up due to rounding. Spot pricing scenario is based on the LBMA gold price as of the close of business on September 11, 2026, rounded to
nearest US$50/oz.
2. Non-IFRS Financial Measure. See Cautionary Statements – Non-IFRS Financial Measures.
3. Go-forward capital obligation associated with the August 2026 update assumes remaining capital costs from August 1, 2026 to commercial production. Refer to
Table 1 for a more detailed breakdown.
4. Under the spot gold price scenario, higher pre-production revenues provide a greater offset to the go-forward capital obligation than under the long-term
consensus pricing scenario.
5. Average free cash flow for the first 5 years is calculated for the periods between 2029 and 2034, inclusive of the pre -production period.
Cariboo Gold Project Update
Project Activity Update
Health and Safety • The Total Recordable Injury Frequency Rate for the Project sits at 1.21 year-to-date for 2026,
with over 2.3 million total person-hours worked project-to-date.
Project Completion • Based on total costs incurred to date, including indirects and owners' costs, overall project
completion is estimated at 22%, as of July 31, 2026.
Underground Development • Approximately 3.0 km of underground development has been completed to date. Underground
development continues from the existing Cow Portal into the Lowhee Zone and along the main
access ramp into the Cow Mountain Zone.
• Development rates continue to improve as headings advance beyond the Lowhee fault, where
enhanced ground support was required, and into more favourable ground conditions in the
Cow Zone.
• Development rates are expected to reach target monthly rates of up to approximately 500
metres by year-end.
• At the mine site complex, earthworks have commenced on the second underground access at
the Valley Portal, which is expected to be collared by mid-September 2026. Once established, it
will provide a second development front and support critical path primary development access
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Project Activity Update
to the Valley and Shaft Zones, which host the majority of the Cariboo Gold deposit's mineral
reserves and mineral resources.
• A total of four (4) portal accesses are planned, with no shafts or hoisting systems. The existing
Cow portal will serve as the primary access for mine equipment and waste haulage, while the
three portals at the Valley Complex will provide secondary access, ventilation, and material
conveyance, respectively.
Site Infrastructure • Water treatment plant – upgrades to the Bonanza Ledge water treatment plant are complete.
Final commissioning continues, with full operation expected in Q3 2026. Excavation for the
Mine Site Complex water treatment plant, which will serve as the primary facility during
operations, has commenced, with the plant slated to be fully operational by the end of 2027.
• Sediment control pond (Bonanza Ledge) – has been completed.
• Waste rock storage facility – construction is progressing with Phase 1a cut and fill completed,
underdrains installation complete, and placement of liner bedding approximately 50%
complete. Completion of Phase 1 is anticipated in mid-2027.
• Permanent camp – the site camp upgrade and expansion to 375 rooms is complete and,
together with other Company-controlled accommodations, is expected to provide sufficient
capacity aligned with peak construction and exploration manpower requirements.
• Construction of other critical infrastructure is progressing.
Early Works • Early works at the mine site complex, which will host the primary processing facility,
commenced in Q2 2026 and include tree clearing and geotechnical drilling.
• Excavation of the Valley Portal and earthworks and foundation construction for the main water
treatment plant at the Mine Site Complex have commenced in Q3 2026. Installation of the
Willow River Bridge, which will provide the Project's primary access once completed, is
expected to begin in Q3 2026.
Transmission Line • All long lead packages, transformer, conductor cabling and high voltage breakers have been
procured and are expected to arrive at site in Q3 2027.
Engineering • Approximately 40% of detailed engineering has been completed.
• Engineering progress status for key planned activities by category is as follows: process plant &
site utilities (10%), water treatment plant (90%), MSC sediment control pond (10%), waste rock
storage facility (100%), MSC civil works (75%), transmission line (100%), overland piping (75%),
and other remaining areas (75%).
Procurement • Procurement and commitments for long-lead items is progressing and includes a total of 466
work contract packages, with overall completion at approximately 44%. Approximately $325
million has been committed to date.
• Major construction contracts have been awarded, including those covering earthworks,
structural steel erection, electrical and instrumentation, site services, the transmission line,
overland piping, and others. Procurement activities for the remaining contract packages are
actively progressing.
Construction Management • Project and Construction Management Services Agreement with JDS Energy & Mining Inc. in
place.
Permitting • The Project obtained all permits necessary for construction, operation, and closure in Q4 2024
with the receipt of the Mines Act (British Columbia) and Environmental Management Act (British
Columbia) permits.
• License of Occupation for the transmission line is expected to be obtained in Q4 2026.
• All remaining authorizations, permit amendments, and routine construction permits are
expected to be obtained in the ordinary course as construction progresses.
Labour and workforce • Construction and exploration workforce at site currently exceeds 350 active personnel and is
expected to ramp-up to up to 360-375 over the coming months.
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Project Activity Update
First Nations and Stakeholder
Engagement
• The Company has entered into a Life of Project Agreement with Lhtako Dené Nation (2020) and
entered into a Participation Agreement with Williams Lake First Nation (2022). Consultation and
engagement with Xatśūll First Nation continues.
• The Company entered into a Support and Benefits Agreement with the District of Wells (2026)
and continues to be an active participant in the local community.
Exploration • Underground development reached the first access point into the Cow Mountain Zone where a
dedicated drill gallery is being advanced to enable infill drilling to support resource conversion,
which is expected to commence at the end of September 2026.
• Up to 20 drill rigs are expected to be active at times throughout 2026 and beyond, as the
various programs overlap and advance, representing up to approximately 160,000 metres of
planned drilling across all targets. Thirteen drill rigs are currently operating across all programs,
including three drills active underground.
Project Development Photos
FIGURE 2: Mine Site Complex processing facility site earthworks underway.