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Exhibit 99.1

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Denison Mines Corp.

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2024 Annual Information Form

March 28, 2025

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About this Annual Information Form

This annual information form (“AIF”) is dated March 28, 2025. Information in this AIF is stated as at December 31, 2024 unless specified otherwise.

In this AIF, references to the “Company” or “Denison” refer to Denison Mines Corp., its subsidiaries and affiliates, or any one of them, as applicable.

This AIF has been prepared in accordance with Canadian securities laws and contains information regarding Denison’s history, business, mineral reserves and resources, the regulatory environment in which Denison does business, the risks that Denison faces and other important information for Denison’s shareholders.

Financial Information

Unless otherwise specified, all dollar amounts referred to in this AIF are stated in Canadian dollars (“CAD”). References to “US$” or “USD” mean United States dollars.

Financial information is generally derived from consolidated financial statements that have been prepared in accordance with International Financial Reporting Standards as issued by the International Accounting Standards Board.

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Caution about Forward-Looking Information

Certain information contained in this AIF and the documents incorporated by reference concerning the business, operations and financial performance and condition of Denison constitutes forward-looking information within the meaning of the United States Private Securities Litigation Reform Act of 1995 and similar Canadian legislation.

Generally, the use of words and phrases like “plans”, “expects”, “is expected”, “budget”, “scheduled”, “estimates”, “forecasts”, “intends”, “anticipates”, or “believes”, or the negatives and/or variations of such words and phrases, or statements that certain actions, events or results “may”, “could”, “would”, “might” or “will” “be taken”, “occur”, “be achieved” or “has the potential to” and similar expressions are intended to identify forward-looking information.

Forward-looking information involves known and unknown risks, uncertainties, material assumptions and other factors that may cause actual results or events to differ materially from those expressed or implied by such forward-looking statements. Denison believes that the expectations and assumptions reflected in this forward-looking information are reasonable, but no assurance can be given that these expectations will prove to be correct. Forward-looking information should not be unduly relied upon. This information speaks only as of the date of this AIF, and Denison will not necessarily update this information, unless required by securities laws.

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Examples of Forward-Looking Information

This AIF contains forward-looking information in a number of places, including statements pertaining to Denison’s:

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Statements relating to “mineral resources” are deemed to be forward-looking information, as they involve the implied assessment, based on certain estimates and assumptions that the mineral resources described can be profitably produced in the future.

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Material Risks

Denison’s actual results could differ materially from those anticipated. Management has identified the following risk factors which could have a material impact on the Company or the trading price of its common shares (“Shares”):

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The risk factors listed above are discussed in more detail later in this AIF (see “Risk Factors”). The risk factors discussed in this AIF are not, and should not be construed as being, exhaustive.

Material Assumptions

The forward-looking statements in this AIF and the documents incorporated by reference are based on material assumptions made by management of the Company, including the following, which may prove to be incorrect:

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Cautionary Notes to U.S. Investors Concerning Resource and Reserve Estimates

As a foreign private issuer reporting under the multijurisdictional disclosure system adopted by the United States, the Company has prepared this AIF in accordance with Canadian securities laws and standards for reporting of mineral resource estimates, which differ in some respects from United States standards. In particular, and without limiting the generality of the foregoing, the terms “measured mineral resources,” “indicated mineral resources,” “inferred mineral resources,” and “mineral resources” used or referenced in this AIF are Canadian mineral disclosure terms as defined in accordance with National Instrument 43-101 — Standards of Disclosure for Mineral Projects (“NI 43-101”) under the guidelines set out in the Canadian Institute of Mining, Metallurgy and Petroleum Standards for Mineral Resources and Mineral Reserves, Definitions and Guidelines, May 2014 (the “CIM Standards”). The Securities and Exchange Commission (the “SEC”) recognizes estimates of “measured mineral resources”, “indicated mineral resources” and “inferred mineral resources”. In addition, the SEC’s definitions of “proven mineral reserves” and “probable mineral reserves” are “substantially similar” to the corresponding definitions under the CIM Standards definition that are required under NI 43-101. Investors are cautioned that while the above terms are “substantially similar” to the corresponding CIM Standards definition, there are differences between the definitions under the United States Securities Exchange Act of 1934, as amended (the “U.S. Exchange Act”) and the CIM Standards definition. Accordingly, there is no assurance any mineral reserves or mineral resources that the Company may report as “proven mineral reserves”, “probable mineral reserves”, “measured mineral resources”, “indicated mineral resources” and “inferred mineral resources” under NI 43-101 would be the same had the Company prepared the mineral reserve or mineral resource estimates under the standards adopted under the U.S. Exchange Act. For the above reasons, information contained in the AIF and other documents incorporated by reference herein containing descriptions of mineral deposits may not be comparable to similar information made public by U.S. companies subject to the reporting and disclosure requirements under the United States federal securities laws and the rules and regulations thereunder. Additionally, investors are cautioned that “inferred mineral resources” have a great amount of uncertainty as to their existence, and great uncertainty as to their economic feasibility. Under Canadian rules, estimates of inferred mineral resources may not form the basis of feasibility or other economic studies, except in limited circumstances. It cannot be assumed that all or any part of an inferred mineral resource will ever be upgraded to a higher category. The term “resource” does not equate to the term “reserves”. Investors should not assume that all or any part of measured or indicated mineral resources will ever be converted into mineral reserves. Investors are also cautioned not to assume that all or any part of an inferred mineral resource exists or is economically mineable.

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About Denison

Denison Mines Corp. is engaged in uranium exploration, development and mining. The registered and head office of Denison is located at 1100 – 40 University Avenue, Toronto, Ontario, M5J 1T1, Canada. Denison’s website address is www.denisonmines.com.

The Shares are listed on the Toronto Stock Exchange (“TSX”) under the symbol “DML” and on the NYSE American under the symbol “DNN.”

Computershare Investor Services Inc. acts as the registrar and transfer agent for the Shares. The address for Computershare Investor Services Inc. is 100 University Avenue, 8th Floor, Toronto, ON, M5J 2Y1, Canada, and the telephone number is 1-800-564-6253.

Denison is a reporting issuer in each of the Canadian provinces and territories. The Shares are also registered under the U.S. Exchange Act, and Denison files periodic reports with the SEC.

Acknowledgement

Denison respectfully acknowledges that its business operates in Canada on lands that are in the traditional territory of Indigenous peoples. Denison’s activities encompass the entire mining life cycle, from early-stage exploration to advanced project evaluation, construction, operation, closure and restoration – with the potential for activities to span many decades. As such, Denison is committed to collaborating with Indigenous peoples and communities to build long-term, respectful, trusting, and mutually beneficial relationships and aspires to avoid any adverse impacts of Denison’s activities and operations.

Denison has adopted an Indigenous Peoples Policy, which reflects the Company’s recognition of the important role of Canadian business in the process of reconciliation with Indigenous peoples in Canada and outlines the Company’s commitment to take action towards advancing reconciliation. A copy of the Indigenous Peoples Policy is available on Denison’s website, in Déne, Cree, English and French languages.

Denison’s Head Office is located in the traditional territory of many nations, including the Mississaugas of the Credit, the Anishnabeg, the Chippewa, the Haudenosaunee and the Wendat peoples, and is now home to many diverse First Nations, Inuit and Métis peoples. Denison also acknowledges that Toronto is covered by Treaty 13 with the Mississaugas of the Credit.

Denison’s mining and mineral exploration operations in Saskatchewan, including its office in Saskatoon and various project interests in northern Saskatchewan, are located in regions covered by Treaty 6, Treaty 8 and Treaty 10, which encompass the traditional lands of the Cree, Dakota, Déne, Lakota, Nakota, Saulteaux, within the homeland of the Métis and within Nuhenéné.

Denison’s flagship Wheeler River uranium project, in particular, is located in northern Saskatchewan within the boundaries of Treaty 10, in the traditional territory of English River First Nation, in the homeland of the Métis and within Nuhenéné.

Denison’s legacy mines operations in the Elliot Lake region of northern Ontario are located within the boundaries of the Robinson Huron Treaty of 1850, signatories to which include the Serpent River First Nation.

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Denison’s Team

At the end of 2024, Denison had a total of 75 active employees, all of whom were employed in Canada. None of the Company’s employees are unionized.

Denison’s Structure

Denison conducts its business through a number of subsidiaries and joint arrangements. The following is a diagram depicting the corporate structure of Denison, its active subsidiaries and corporate and partnership joint arrangements, including the name, jurisdiction of incorporation and proportion of ownership interest in each, as at December 31, 2024.

JCU (Canada) Exploration Company, Ltd. (“JCU”) is owned by Denison (50%) and UEX Corporation (“UEX”, 50%). UEX, a wholly-owned subsidiary of Uranium Energy Corp., is manager of JCU, and JCU’s operations are managed in accordance with a shareholders agreement between Denison, UEX and JCU.

As at the date hereof, the Waterbury Lake Uranium Limited Partnership (“WLULP”) is held by Denison (70.55%) and Korea Waterbury Uranium Limited Partnership (“KWULP”) (29.45%) as limited partners and Waterbury Lake Uranium Corporation (“WLUC”) (0.02%), as general partner.

The Formation of Denison Mines Corp.

The Denison name has a long history in the Canadian uranium mining industry. Based on company archives, Denison’s involvement in the uranium mining industry dates back to 1954, when a predecessor to modern Denison acquired uranium claims in the Elliot Lake region.

Modern Denison was established by articles of amalgamation as International Uranium Corporation (“IUC”) on May 9, 1997 pursuant to the Business Corporations Act (Ontario) (the “OBCA”). On December 1, 2006, IUC completed a plan of arrangement (the “IUC Arrangement”) with Denison Mines Inc. (“DMI”). Pursuant to the IUC Arrangement, all of the issued and outstanding shares of DMI were acquired in exchange for IUC’s shares. Effective December 1, 2006, IUC’s articles were amended to change its name to “Denison Mines Corp.”

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Denison subsequently completed a plan of arrangement with Energy Fuels Inc. in 2012 and filed articles of amalgamation on January 1, 2014, July 1, 2014 and July 3, 2014 in connection with Denison’s acquisitions of JNR Resources Inc. and Fission Energy Corp.

Denison Overview

Uranium Mining, Development, and Exploration

Denison’s uranium property interests are held directly by the Company and/or indirectly through DMI, Denison Waterbury Corp. and Denison AB Holdings Corp.

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Toll Milling

Denison is a party to a toll-milling arrangement through its 22.50% interest in the MLJV, whereby ore is processed for the Cigar Lake Joint Venture (“CLJV”) at the McClean Lake processing facility (the “Cigar Toll Milling”). In February 2017, Denison completed a transaction (the “Ecora Transaction”) with Ecora Resources PLC (“Ecora”) and its wholly owned subsidiary Centaurus Royalties Ltd. to raise gross proceeds to Denison of $43,500,000. The Ecora Transaction monetized Denison’s future share of the Cigar Toll Milling, providing Denison with the financial flexibility to advance its interests in the Athabasca Basin, including the Wheeler River project. See “Denison’s Operations – Cigar Lake Toll Milling – Ecora Transaction”.

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Developments Over the Last Three Years

2022…

Project Developments – Wheeler River

In February, Denison announced that it completed three drill holes during the fall of 2021 to follow up on the discovery of high-grade uranium mineralization in drill hole GWR-045 at Wheeler River’s Phoenix deposit (“Phoenix”), which hole was located outside of the previously defined extent of the high-grade domain of Phoenix Zone A. All three follow-up holes returned intervals of high-grade uranium mineralization. The results were highlighted by drill hole GWR-049, which was expected to intersect a narrow high-grade interval according to then-current modeling, but instead returned 24.9% eU3O8 over 4.2 metres.

In July, Denison announced that it received approval from the Province of Saskatchewan to prepare, construct, and operate the facilities required to carry out the in-situ recovery (“ISR”) Feasibility Field Test (“FFT”) planned for the Phoenix deposit. The FFT was designed to use the existing commercial-scale ISR test pattern to perform a combined assessment of the Phoenix deposit’s hydraulic flow properties along with the leaching characteristics that had been assessed through the metallurgical core-leach testing program. The approval was granted by the Saskatchewan Minister of Environment and authorizes Denison to operate “pollutant control facilities”, which is typical for mining operations and allows for the management of material recovered from mineral extraction through to wastewater treatment, discharge, and storage (as applicable). The approval followed the completion of a process involving the review of and consultation on the Company’s permit application and supporting materials related to the FFT.

In August, the Company announced that it had received a Licence to Possess, Use, Store and Transfer a Nuclear Substance from the Canadian Nuclear Safety Commission (“CNSC”). With the receipt of this approval, the Company was fully permitted to operate the FFT facility and carry out the process of recovering a uranium bearing solution from the Phoenix ore body.

Also in August, Denison announced the substantial completion of extensive metallurgical test work to define the mechanical components for the planned Phoenix processing plant as part of the FS underway for Wheeler River. The test work confirmed the ability to produce a yellowcake product that meets industry standard ASTM C967-13 specifications.

In September, the Company reported the completion of the construction and wet commissioning of the lixiviant injection system for the FFT and commencement of the leaching phase of the FFT.

In October, the Company announced that it had successfully recovered uranium bearing solution from the ISR FFT at targeted rates and grades, indicating that the hydrogeological system at Phoenix was responding as expected with pH trends, flow characteristics, and uranium recovery meeting expectations. The preliminary results demonstrated the successful acidification of the test pattern and recovery of uranium using the ISR mining method. Given the highly successful results of the FFT, lixiviant injection ceased, and operations at the Phoenix FFT site transitioned from the leaching phase of the FFT to the neutralization phase.

Also in October, Denison announced a significant regulatory milestone for Wheeler River with the submission of the draft Environmental Impact Statement (“EIS”) to the Saskatchewan Ministry of Environment (“SKMOE”) and the CNSC as part of the Environmental Assessment (“EA”) process being undertaken in accordance with the requirements of the Canadian Environmental Assessment Act, 2012 (“CEAA 2012”) and the Saskatchewan Environmental Assessment Act. The EIS submission outlines the Company’s assessment of the potential effects, including applicable mitigation measures, of the proposed ISR uranium mine and processing plant planned for Wheeler River, and reflects several years of baseline environmental data collection, technical assessments, plus extensive engagement and consultation with Indigenous and non-Indigenous interested parties.

In November, Denison announced the CNSC had completed its conformity review of the draft EIS submitted for the proposed ISR uranium mine and processing plant. The CNSC determined the draft EIS met the requirements for the advancement of the EA process, and the federal technical review of the EIS commenced.

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In December, Denison announced highly successful results from long-term core leach metallurgical testing completed to further support the establishment of ISR production and recovery curves to be used in the Phoenix FS. The Company completed a long-term test of a representative intact core sample using specialized equipment to replicate in-situ leaching conditions of the Phoenix deposit. The results were highlighted by: (a) overall recovery of uranium in excess of 97%, demonstrating excellent recovery of uranium from intact high-grade core without the use of permeability enhancement; (b) average recovered solution uranium head grade of 18.3 grams per litre (“g/L”), exceeding the assumed 15 g/L uranium head grade being used in plant designs; (c) continuous intact core leach testing over a period of 377 days, with uranium recovery head grades consistently maintained above 5 g/L during the final stages of the production curve and then declining during the ramp-down stage; and (d) maximum recovered solution uranium head grade of 49.8 g/L achieved using similar lixiviant concentrations as to those used during the FFT.

And in December, Denison reported that the neutralization phase of the FFT had been successfully completed, advising that sampling of monitoring wells (“MWs”) around the FFT site confirmed the successful restoration of the leaching zone to environmentally acceptable pH conditions, as outlined in the applicable regulatory approvals for the FFT. The neutralization phase was initiated in mid-October, following the highly successful completion of the leaching phase of the FFT, and was designed to confirm certain environmental assessment assumptions and verify the efficiency and effectiveness of the neutralization process planned for ISR mining at Phoenix. The FFT was highlighted by the recovery of 14,400 pounds of U3O8 dissolved in solutions generated during the leaching and neutralization phases of the test. The final phase of the FFT, involving the management of the recovered solution, was undertaken in 2023.

Other Project Developments

In January, the Company announced that the CNSC approved an amendment to the operating licence for the MLJV and MWJV operations, which allows for the expansion of the McClean Lake Tailings Management Facility (“TMF”) and accepts the associated revised Preliminary Decommissioning Plan (“PDP”) and cost estimate. See “Denison’s Operations – McClean Lake Mill & Cigar Lake Toll Milling – Mill Licence” for more information.

In March, Denison reported that multiple new high-grade intercepts of unconformity-hosted uranium mineralization were discovered in the final three drill holes completed during the winter 2022 exploration program at the Waterfound property, operated by Orano Canada. Denison holds an effective 24.68% ownership interest in Waterfound through its direct interest in the joint venture and its 50% ownership of JCU. The results were highlighted by drill hole WF-68, which returned a broad zone of uranium mineralization, including a peak interval of 5.91% eU3O8 over 3.9 metres (0.05% eU3O8 cut-off) with a sub-interval grading 25.30% eU3O8 over 0.7 metres, located approximately 800 metres west, along the La Rocque Conductive Corridor, of the previously discovered high-grade mineralization (including 4.49% U3O8 over 10.53 metres) at the Alligator Zone.

In April, Denison completed the sale of 40,000 pounds of U3O8, representing the Company’s share of production from the patented Surface Access Borehole Resource Extraction (“SABRE”) mining method test mining program completed at the at the McClean Lake property in 2021. The uranium was sold at a price of $74.65 (US$59.25) per pound U3O8. The five-year test program was highlighted by the completion of the final stage of the program from May to September 2021 with four mining cavities successfully excavated to produce approximately 1,500 tonnes of high-value ore ranging in grade from 4% U3O8 to 11% U3O8. The program was concluded with no safety, environmental or radiological incidents and confirmed the ability to achieve key operating objectives associated with the test program – including targets for cavity diameter, rates of recovery, and mine production rates. The majority of the ore recovered from the test mining program was transferred to the McClean Lake mill, resulting in the production of approximately 176,000 pounds of U3O8 (Denison’s share: approximately 40,000 pounds of U3O8) in the fourth quarter of 2021.

In September, Denison announced that assays received from exploration drilling completed at McClean Lake during the winter of 2022 resulted in a significant expansion of the high-grade unconformity-hosted zone of uranium mineralization discovered in 2021 between the McClean South 8W and 8E pods. Ten drill holes completed during 2022 by Orano Canada returned notable uranium mineralization, including drill hole MCS-58, which returned 2.96% U3O8 over 15.5 metres, including 24.49% U3O8 over 1.5 metres, located approximately 54 metres to the southeast of drill hole MCS-34, which was completed in 2021 and returned a mineralized interval of 8.67% U3O8 over 13.5 metres. Overall, the results from 2022 have successfully expanded the footprint of the mineralized zone to approximately 180 metres in strike length.

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Also in September, Denison announced that uranium mineralization was encountered in three of the seven drill holes completed during the summer exploration program at Waterfound, highlighted by drill hole WF-74A, which intersected 4.75% eU3O8 over 13.3 metres, including a sub-interval grading 25.23% eU3O8 over 0.5 metres. The mineralized intersection from WF-74A represents the best mineralized hole drilled on the Waterfound property to date and highlights the potential for the discovery of additional high-grade uranium mineralization further along strike to the west of the Alligator Zone.

Financing Developments

In January, the Company amended and extended its credit facility with the Bank of Nova Scotia (the “Credit Facility”) to January 31, 2023.

During 2022, the Company issued 11,042,862 Shares under an at-the-market equity offering program (the “2021 ATM Program”) qualified by a short form base shelf prospectus filed with the securities regulatory authorities in each of the provinces and territories of Canada and a registration statement on Form F-10, as amended (SEC File No. 333-258939). The Shares were issued on the market at an average price of $1.83 per Share for aggregate gross proceeds of $20,200,000. Denison also recognized issue costs of $599,000 related to the 2021 ATM Program Share issuances which includes $404,000 of commissions and $195,000 other costs associated with the maintenance of the 2021 ATM Program.

In December, the Company amended the terms of the Credit Facility to extend the maturity date to January 31, 2024, and to increase the credit available under the facility to cover additional standby letters of credit with respect to environmental obligations associated with the FFT activities at Wheeler River.

Corporate Developments

Also in January, the Company executed a Repayment Schedule Agreement (the “Repayment Agreement”) with Uranium Industry a.s. (“UI”) pursuant to which the parties negotiated the repayment of the debt owing from UI to Denison with respect to the contingent proceeds of Denison’s sale to UI of its interest in the Gurvan Saihan Joint Venture in Mongolia in 2015 (the “Mongolia Transaction”). In accordance with the Repayment Agreement, the Company received aggregate installment payments in 2022 of US$4,800,000.

And in January, Denison announced the appointment of Ms. Laurie Sterritt to the Board of Directors of the Company (the “Board”) and the appointment of Mr. Kevin Himbeault as the Company’s Vice President Plant Operations & Regulatory Affairs.

In February, Mr. Jun Gon Kim resigned from the Board. Mr. Yun Chang Jeong joined the Board in early March, filling the vacancy created by Mr. Kim’s resignation.

In April, Denison released its inaugural ESG Report regarding the Company’s environmental, social and governance initiatives and demonstrating its ongoing commitment to sustainability and transparency. Denison’s ESG Reports focus on key ESG topics including the Company’s objective to maintain excellence in corporate governance practices, “best in class” engagement with communities potentially impacted by its activities, diversity in the Company’s workforce, and robust assessments of the environment and biodiversity in the regions within which it operates.

And in April, in connection with the updated PDP and related decrease in the financial assurances required for the MLJV and MWJV reclamation obligation, the Company entered into a further amendment with respect to the Credit Facility pursuant to which the pledged amount of cash required under the Credit Facility was decreased and the additional cash collateral was released.

In May, at Denison’s Annual General Meeting of Shareholders (the “2024 AGM”), Mr. Bob Dengler did not stand for re-election to the Board.

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In June, Denison and Kineepik Métis Local #9 (“KML”) entered into a Participation and Funding Agreement (the “KML PFA”), which expresses Denison’s and KML’s mutual commitment to the co-development of an agreement supporting the advancement of the Phoenix ISR project. The KML PFA builds on an existing letter agreement between Denison and KML with respect to the support of KML’s contributions to, and participation in, the Federal and Provincial EA process. The parties also entered into an Exploration Agreement (the “KML Exploration Agreement”) in respect of Denison’s exploration and evaluation activities within KML’s Land and Occupancy Area. These agreements reflect Denison’s commitment to the principles set out in the Company’s Indigenous Peoples Policy (“IPP”) and advancing reconciliation through taking action.

In October, Denison announced that it entered into an exploration agreement (the “YNLRO Exploration Agreement”) with the Ya’thi Néné Lands and Resources Office (“YNLRO”), Hatchet Lake Denesułiné First Nation, Black Lake Denesułiné First Nation, Fond du Lac Denesułiné First Nation (collectively, the “Athabasca Nations”) and the Northern Hamlet of Stony Rapids, the Northern Settlement of Uranium City, the Northern Settlement of Wollaston Lake and the Northern Settlement of Camsell Portage (collectively, the “Athabasca Communities”) in respect of Denison’s exploration and evaluation activities within the traditional territory of the Athabasca Nations (the “Nuhenéné”). The YNLRO Exploration Agreement expresses the parties’ intention to build a long-term relationship between Denison and the YNLRO, Athabasca Nations, and Athabasca Communities. Denison wishes to conduct and advance its exploration activities in a sustainable manner that respects the Athabasca Nations’ Indigenous rights, advances reconciliation with Indigenous peoples, and provides economic opportunities and other benefits to the Athabasca Communities in an authentic, cooperative and respectful way.

And in December, Mr. David Bronkhorst retired from his position as Vice President Operations of Denison, remaining with the Company in a technical advisory role. Concurrently therewith, Mr. Himbeault became Vice President Operations & Regulatory Affairs.

2023…

Project Developments – Wheeler River

In August, Denison filed a technical report summarizing the results of (i) the feasibility study completed for ISR mining of the high-grade Phoenix uranium deposit (the “Phoenix FS”); and (ii) a cost update to the Pre-Feasibility Study (“PFS”) for the Wheeler River project completed in 2018 for conventional underground mining of the basement-hosted Gryphon uranium deposit (“Gryphon PFS Update”). The results of the respective studies illustrated that both deposits have the potential to be competitive with the lowest cost uranium mining operations in the world. See “Wheeler River” for more details.

And in August, reflective of the extensive efforts undertaken by and for the Company, the CNSC deemed complete the Company’s responses to approximately 250 EIS information requests from the Federal Indigenous Review Team (“FIRT”). In November 2023, a subsequent round of information requests was received from the CNSC, seeking additional details for responses not fully accepted by the FIRT.

In September, Denison announced the signing of a Shared Prosperity Agreement (“SPA”) with English River First Nation (“ERFN”) supporting the development and operation of the Wheeler River project. The SPA received support from a substantial majority of ERFN members who participated in a ratification vote on its key terms. The signing of the SPA follows years of active engagement, including a four-month-long ERFN-led community consultation process ahead of the ratification vote, and represents a significant milestone in the history of both Denison’s relationship with ERFN and the Wheeler River project.

In October, the SKMOE confirmed its satisfaction with Denison’s comment responses and proposed EIS updates. The confirmation indicates that Denison could finalize the EIS for the purpose of obtaining a Provincial EA approval, however this would delink the coordinated Provincial – Federal EA process, which was not expected to provide a meaningful schedule advantage for the Phoenix project. Denison plans to submit one version of the final EIS to both authorities once the FIRT information requests have been resolved.

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In November, the Company announced the successful completion of the recovered solution management phase of the ISR FFT. The solution recovered during the FFT was stored on site and this final phase of the FFT involved the treatment of the recovered solution via an on-site purpose-built treatment system. Following treatment, a uranium precipitate product and a treated effluent were produced. The mineralized precipitates were recovered from the process with over 99.99% efficiency. The treated effluent was tested to ensure compliance with permit conditions before being injected into a designated subsurface area.

Other Project Developments

In April, Denison announced the completion of an internal conceptual mining study examining the potential application of the ISR mining method at the Midwest project. The concept study was prepared by Denison in 2022 and formally issued to the MWJV in early 2023. Based on the positive results of the concept study, the MWJV approved the completion of additional ISR-related work for Midwest in 2023 and 2024.

And in April, Denison reported the discovery of high-grade sandstone-hosted uranium mineralization approximately 30 metres above the unconformity in drill hole MS 23-10A, which was completed as part of the 2023 winter exploration program at the Moon Lake South property. The intersection in MS 23-10A returned 2.46% U3O8 over 8.0 metres, including a sub-interval grading 3.71% U3O8 over 4.5 metres. This result represents the best drill hole completed on the Moon Lake South property to date.

In November, the Company announced the completion of an inaugural ISR field test program at THT on the Waterbury Lake property. The program included (i) the installation of an eight well ISR test pattern designed to collect an initial database of hydrogeological data, (ii) testing of a permeability enhancement technique, (iii) the completion of hydrogeologic test work, highlighted by the achievement of hydraulic conductivity values consistent with those from the Waterbury PEA, and (iv) the execution of an ion tracer test which established a 10 hour breakthrough time between the injection and extraction wells, while also demonstrating hydraulic control of the injected solution. Overall, the program successfully achieved each of its planned objectives.

Financing Developments

In October, Denison completed a bought deal equity financing resulting in the issuance of 37,000,000 shares at a price of $2.03 (US$1.49) per share for total gross proceeds of $75.1 million (US$55.1 million). The Company intends to use the net proceeds from the offering to fund (1) the advancement of the proposed Phoenix ISR uranium mining operation through the procurement of long lead items (including associated engineering, testing and design) identified during the ongoing Front End Engineering Design (“FEED”) process and the Phoenix FS; (2) exploration and evaluation expenditures; and (3) general corporate and administrative expenses, including those in support of corporate development activities, and working capital requirements.

And in October, the Company completed a $15 million strategic investment in F3 Uranium Corp. (“F3”) with the acquisition of unsecured convertible debentures (the “Debentures”), which carry a 9% coupon and will be convertible at Denison’s option into common shares of F3 at a conversion price of $0.56 per share. F3 has the right to pay up to one third of the quarterly interest payable by issuing common shares. F3 will also have certain redemption rights on or after the third anniversary of issuance of the Debentures and/or in the event of an F3 change of control.

In December, the Company amended and extended its Credit Facility to January 31, 2025.

In 2023, the Company sold 200,000 pounds U3O8 at an average selling price of $99.50 per pound U3O8 (US$73.38 per pound U3O8), representing a realized gain on sale of $12.6 million (US$8.8 million), based on Denison’s average acquisition cost of $36.67 per pound U3O8 (US$29.66 per pound U3O8). As at December 31, 2023, the Company’s remaining uranium portfolio had increased in value by 228% since acquisition, to $120.35 per pound U3O8 (US$91.00 per pound U3O8), for an aggregate value of approximately $276.8 million (US$209.3 million).

During 2023, the Company issued 19,786,160 shares under the 2021 ATM Program. The Shares were issued at an average price of $1.91 per share for aggregate gross proceeds of $37,877,000. The Company also recognized costs of $845,000 related to the maintenance of the 2021 ATM Program and Share issuances, which includes $757,000 of commissions, for net proceeds after commissions of $37,130,000.

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Corporate Developments

In February, Mr. Yun Chang Jeong resigned from the Board. Mr. Byeong Min An joined the Board in early March, filling the vacancy created by Mr. Jeong’s resignation.

In September, Ms. Elizabeth Sidle was appointed Interim Chief Financial Officer of the Company, in addition to her current role as Vice President Finance, in connection with the leave of absence and subsequent departure from the Company of Mr. McDonald, former Executive Vice President & Chief Financial Officer. Ms. Sidle was appointed Chief Financial Officer in December.

In December, Mr. Geoff Smith joined Denison in the position of Vice President Corporate Development & Commercial, focused on supporting Denison’s investor and customer engagement, the evaluation and execution of growth opportunities and financing arrangements, and the development and oversight of the Company’s uranium sales and contracting strategies.

2024…

Project Developments – Wheeler River

In January, Denison awarded a contract for approximately $16 million to Wood Canada Limited (“Wood”), for the completion of detailed design engineering for Phoenix. The contracted scope of the facilities to be designed by Wood is extensive. The work commenced in the first quarter of 2024 and is expected to be substantially completed in the third quarter of 2025. Throughout 2024, the Company continued to focus its efforts on the advancement of Phoenix towards a final investment decision (“FID”), in support of its objective to achieve first production by the first half of 2028, including the advancement of Phoenix detailed design engineering activities. Total engineering completion at end of 2024 was approximately 65%, supported by finalization of process design, piping and instrumentation diagrams, hazard and operability studies, as well as the selection of major process equipment and electrical distribution infrastructure.

In March, Denison signed a Sustainable Communities Investment Agreement (the “SCIA”) with the municipalities of the Northern Village of Beauval, the Northern Village of Île-à-la Crosse, the Northern Hamlet of Jans Bay, and the Northern Hamlet of Cole Bay (the “SCIA Communities”). The SCIA reflects a common goal of facilitating qualified businesses and workers in benefitting from opportunities associated with the development of the Wheeler River project. The SCIA establishes commitments for funding to support community development initiatives, focused on contributing to the current and future economic prosperity and sustainability of the Communities by promoting economic development and investments in capital projects, job creation and training, housing, education, and other initiatives. In consideration for such contributions to the Communities’ initiatives, the Communities have provided their consent and support for the Wheeler River project and have committed, amongst other things, to support all regulatory approvals issued for the Wheeler River project related to exploration, evaluation, development, operation, reclamation, and closure activities.

In early July, Denison announced the signing of a Mutual Benefits Agreement (“MBA”) with KML and a Community Benefit Agreement (“CBA”) with the northern Village of Pinehouse Lake (“Pinehouse”), in support of the development and operation of Wheeler River. The MBA acknowledges that Wheeler River is located within KML’s Land and Occupancy Area in northern Saskatchewan and provides KML’s consent and support to advance the project. Additionally, the MBA recognizes that the development and operation of Wheeler River can support KML in advancing its social and economic development aspirations, while mitigating the impacts on the local environment and KML members. The MBA provides KML and its Métis members an important role in environmental monitoring and commits to the sharing of benefits from the successful operation of Wheeler River – including benefits from community investment, business opportunities, employment and training opportunities, and financial compensation. The CBA acknowledges that Pinehouse is the closest residential community to Wheeler River by road, which relies on much of the same regional infrastructure that Denison will rely on as it advances the project. Pinehouse has provided its consent and support for Wheeler River, while Denison, on behalf of the Wheeler River Joint Venture (“WRJV”), is committed to help Pinehouse develop its own capacity to take advantage of economic and other development opportunities in connection with the advancement and operation of the project.

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Multiple key regulatory milestones were achieved in late 2024, including (i) completion of the technical review phase of the federal EA approval process in November, (ii) acceptance by the CNSC of the EIS in December, and (iii) the CNSC’s determination of the sufficiency of Denison’s application for a Licence to Prepare and Construct a Uranium Mine and Mill (“Licence to Construct”), in November. These accomplishments indicate that the CSNC staff support the advancement of the Phoenix project. Accordingly, the CNSC Registrar has set the schedule for the CNSC public hearing for Wheeler River. The hearing is scheduled to be held in two parts (October 8, 2025, and December 8 to 12, 2025) and represents the final step in the federal approval process for Wheeler River’s EA and Licence to Construct.

In October 2024, Denison submitted a final EIS to the SKMOE, in substantially the same form as the EIS that has been submitted to the CNSC. The province completed a public and Indigenous review period on the EIS in November and December 2024, of which the comments received will be considered in the issuance of a Ministerial Decision for the EA.

For further details, see “Wheeler River” and “Environmental, Health, Safety and Sustainability Matters” below.

In October 2024, the WRJV Management Committee approved the findings and recommendations of the Phoenix FS, which became an Approved Development Program (“ADP”) under the WRJV Agreement, providing the WRJV’s approval for development and construction of the project in accordance with the Phoenix FS. Denison has not yet made a FID with respect to the Phoenix project, pending project EA and License to Construct approval.

At the October 2024 meeting of the WRJV Management Committee, JCU abstained from voting on the ADP. In accordance with the terms of the WRJV Agreement, non-support of the ADP by a participant means that such participant is no longer liable for its cost share of WRJV expenditures. As a result of JCU’s non-support through abstention, Denison has funded, and expects to continue to fund, 100% of the project expenditures from October 2024. The WRJV Agreement further requires that a participant who does not support an ADP must sell or transfer their interest. UEX, as operator of JCU, has notified Denison that it does not agree that JCU’s abstention from the ADP vote should be taken as non-support for the ADP and the sale or transfer of JCU’s participating interest in the WRJV has not yet occurred. See “Legal and Regulatory Proceedings” for further information.

Other Project Developments

In January, Denison and Orano Canada announced that the MLJV has approved a restart of uranium mining operations using the joint venture’s patented SABRE mining method. Mining is planned to commence at the McClean North deposit in 2025. Activities in 2024 focused on preparations necessary to ready the existing SABRE mining site and equipment for continuous commercial operations, as well as the installation of pilot holes for the first mining cavities planned for excavation. See “Denison Operations-SABRE Mining Program” for further details.

And in January, Denison entered into an agreement (the “KLP Agreement”) with Grounded Lithium Corp. (“Grounded Lithium”) with respect to the Kindersley Lithium Project (“KLP”) in Saskatchewan. The KLP Agreement includes a series of earn-in options, with each earn-in option being comprised of a cash payment to Grounded Lithium as well as project expenditures to advance KLP. The investment in KLP was seen as an opportunity for Denison to leverage its technical expertise to potentially unlock greater value for the project. Should Denison complete all three earn-in options, it will have made cumulative cash payments to Grounded Lithium of $3.2 million and have funded $12 million in project expenditures to earn a 75% working interest in the KLP. Upon funding the total amounts of each earn-in option phase, Denison has the right to either exercise the earn-in option and acquire the working interest associated with that phase or move on to the ensuing option phase. The KLP Agreement terminates on the earliest of: (i) Denison electing to acquire its working interest and convert to a formal joint venture or to terminate, (ii) June 30, 2028, or (iii) a date as otherwise agreed between the parties.

In February, the Company announced its acquisition of fixed and mobile MaxPERF Tool Systems from Penetrators Canada Inc. (“Penetrators”). The MaxPERF Tool Systems have been successfully deployed several times as a method of permeability enhancement in ISR field studies conducted on the Company’s potential ISR mining projects, including at the Phoenix deposit. Penetrators has also agreed to work exclusively with Denison for a 10-year period with respect to the use of the MaxPERF Tool Systems for uranium mining applications, and related services, in Saskatchewan.

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In June, Denison and Orano Canada announced the completion of an ISR field test program at Midwest. The program involved drilling ten small diameter boreholes within the Midwest Main deposit, primarily undertaken to evaluate site-specific conditions for ISR mining. A series of tests were successfully performed on each borehole, creating an extensive database of geological, hydrogeological, geotechnical, and metallurgical data and validating certain key assumptions in the previously completed concept study evaluating the potential use of ISR mining at Midwest. For further details see “Mineral Properties – Other Athabasca and Exploration Properties - Midwest 2024 Activities”.

In September, Denison executed an option agreement with Foremost Clean Energy Ltd (“Foremost”), which grants Foremost a multi-phase option to acquire up to 70% of Denison’s interest in 10 non-core uranium exploration properties (the “Foremost Transaction”). Pursuant to the Foremost Transaction, Foremost would acquire such total interests upon completion of a combination of direct payments to Denison and funding of exploration expenditures with an aggregate value of up to approximately $30 million. In October 2024, Foremost completed the conditions for the first tranche of the option, pursuant to which Denison received an upfront payment in Foremost common shares, and in November 2024, Denison participated in a Foremost equity offering. At December 31, 2024, Denison owned ~19.13% of the outstanding common shares of Foremost. If Foremost completes the remaining two phases of the Foremost Transaction, Denison will receive further cash and/or common share milestone payments of $4.5 million and Foremost will fund $20 million in project exploration expenditures.

In November, Denison executed an acquisition agreement with Cosa Resources Corp. (“Cosa”) pursuant to which Cosa agreed to acquire a 70% interest in three of Denison’s portfolio uranium exploration properties in exchange for approximately 14.2 million Cosa common shares, $2.25 million in deferred equity consideration, and a commitment to spend $6.5 million in exploration expenditures on the properties (the “Cosa Transaction”).

Financing Developments

In April, Denison completed the sale of 100,000 pounds of U3O8 from its physical uranium holdings, at a price of $135.98 (US$100.00) per pound. Denison acquired its physical uranium position in 2021 at an average cost of US$29.65 per pound U3O8.

In December, the Company completed a private placement of 3,000,000 Shares that qualify as “flow-through shares” for purposes of the Income Tax Act (Canada) at a price of $4.70 per share for gross proceeds of approximately $14,100,000, the proceeds of which are to be used on the Company’s exploration activities in 2025. The income tax benefits of this issue were renounced to subscribers with an effective date of December 31, 2024.

Corporate Developments

In March, Mr. Byeong Min An resigned from the Board. Mr. Jong Ho Hong joined the Board in March, filling the vacancy created by Mr. An’s resignation.

In May, in connection with the 2024 AGM, changes were made to the composition of the Company’s Board of Directors, with Mr. Ron Hochstein not standing for re-election at the meeting, and Ms. Jennifer Traub, a partner in the Securities Group, and Co-Chair of the Mining Group, at Cassels Brock & Blackwell LLP, was appointed Chair of the Board.

2025 Recent Developments…

In January, the Company closed the Cosa Transaction, and Denison and Cosa formed three uranium exploration joint ventures. In February, the Company participated in a Cosa equity offering, and upon completion Denison owned 19.95% of Cosa shares on a partially-diluted basis.

In February, the CNSC Registrar set the schedule for the CNSC Hearing for Wheeler River. The Hearing is scheduled to be held in two parts (October 8, 2025, and December 8 to 12, 2025) and represents the final step in the federal approval process for the Project’s EA and Licence to Prepare and Construct a Uranium Mine and Mill.

In March, there were a number of Board changes, with the appointment of Mr. Ken Hartwick, former President & CEO of Ontario Power Generation, the retirement of Mr. Brian Edgar, after 20 years of service to the Company, the resignation of Mr. Jong Ho Hong, and the appointment of Mr. Jinsu Baik to fill the vacancy created by Mr. Hong’s resignation.

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The Uranium Industry 2024

In 2024, the long-term price of U3O8 steadily increased, finishing the year up approximately 16% from the end of 2023, which represents a 15-year high. This comes after a significant increase during 2023 of 33% from US$51 per pound U3O8 at the end of 2022 to US$68 per pound U3O8 at the end of 2023. The Company believes the strengthening long-term price over the course of 2024 is representative of strong underlying market fundamentals for uranium. In January 2024, the spot price for uranium surpassed US$100 per pound U3O8 for the first time since 2008. For the balance of 2024, the spot price converged with the long-term price at around US$80 per pound U3O8 before falling slightly below the long-term price near the end of the year and finishing the year down 20%. The spot price reflects sporadic discretionary buying and selling activity and, as a result, continues to experience greater price volatility than the long-term price, which reflects pricing that typically comes from producer to consumer contracting in the form of multi-year supply contracts. Generally, a significant majority of uranium sales occur via long-term supply agreements, with comparatively smaller annual volumes clearing through the spot market.

The Company believes the current uranium market environment demonstrates notable similarities to the last time prices reached these levels. In the early 2000s, highly enriched uranium (HEU) and other former Soviet Union supplies remained a market hangover from the Cold War with elevated inventory levels weighing on prices for years with limited new supply coming online. Ultimately, this period of low prices, then compounded with adverse supply shocks, created a favourable environment for uranium prices in future years when paired with significant expected demand growth driven by ambitious plans for nuclear power in China.

Meaningful new sources of supply were scarce, due to years of under investment, at a time of rapid demand growth. The Japanese tsunami and associated Fukushima nuclear incident in 2011 disrupted the market and set in motion a similar period of low prices and excess inventories. Given the sudden shut-down of the Japanese nuclear fleet and other reductions in demand, excess uranium inventories and excess enrichment capacity, which provided the ability to create additional uranium supply, catalyzed a downward shock to price. During this extended period, prices were below the cost of production for many producers, leading to the shutdown of multiple mines and a sharp reduction in investment in new exploration and development activities across the sector.

After years of supply discipline, and the accumulation of physical uranium positions amongst financial investors, the market reached an inflection point followed by five consecutive years of long-term price increases between 2020 and 2024, reflective of a market transitioning to be driven by the cost of future production rather than by the availability of surplus inventories. Looking ahead, the Company believes that increasing demand for nuclear energy, coupled with a prolonged period of limited investment in new supply, creates supply-demand dynamics that are supportive of strong uranium prices for the foreseeable future.

During 2024, investor interest in the uranium and nuclear energy sectors accelerated. This is believed to largely be driven by a continued focus on global goals to achieve net-zero carbon emissions, and the growing recognition of the necessary role for nuclear energy in the “clean energy transition”. In assessing the potential paths to reduce carbon emissions many nations, policymakers, interest groups, and businesses have recognized the critical role that existing or planned future nuclear power plants could play in achieving decarbonization objectives. The Company believes these positive nuclear demand fundamentals support expectations for robust uranium markets. There is also increasing support from large technology companies that have announced partnerships with nuclear utilities indicating a desire for reliable and emission-free electricity to meet expected growth in artificial intelligence and data centres’ electricity needs. This includes a 2024 commitment announced by Microsoft to support the restart of one of the Three Mile Island nuclear reactors and Amazon’s agreement to support small modular nuclear reactor projects with Dominion Energy.

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Uranium Demand

There is global focus on the importance of nuclear power in enabling the achievement of carbon emission goals and responding to growing energy demands. This recognition was further enshrined as over 20 nations pledged to triple nuclear energy generation capacity by 2050 at COP28 in Dubai in December 2023. This support continued to grow with now over 30 nations pledging such support as of COP29 in Baku in November 2024. The Company believes this wide-spread government support for nuclear energy represents a paradigm shift. In addition to the renewed commitment to nuclear from powerhouse nations like Japan, Korea, France, and the United States in recent years, positive nuclear demand developments occurred in many nations in 2024. Three notable nuclear reactor projects that had been in construction for a decade reached commercial operations in 2024 including Vogtle 4 in the United States, Shin Hanul 2 in South Korea, and Barakah 4 in the United Arab Emirates. China continues to be a major source of growth for nuclear energy, with UxC LLC (“UxC”) reporting that China currently has 31 reactors under construction, and 12 new build projects in the licensing process.

In Canada, Ontario Power Generation (“OPG”) announced refurbishment plans for its Darlington nuclear plant, and Bruce Power continued its ongoing refurbishment efforts. OPG also announced reactor life extension projects at the Pickering B station and has begun planning a new nuclear plant, which could accommodate up to 10,000 megawatts of new generation capacity. Additionally, small modular reactors (“SMRs”) are being advanced in both Ontario and Saskatchewan, with OPG targeting completion of its first SMR project before 2030. In Japan, two boiling water reactors (“BWR”) reactors were restarted in 2024, becoming the first BWRs to restart since the 2011 Fukushima accident.

Taken together, forecasts from UxC for global reactor units and nuclear capacity in 2035 is 552 units and 514 gigawatts electrical (“GWe”) installed capacity (estimated as of Q4’2024) – representing a 30% increase in global nuclear power generation from 439 units producing 396 GWe as of December 2024. UxC forecasts nuclear generation capacity growth to translate into similar increases in demand for uranium and forecasts 2035 base case uranium demand of 253 million pounds U3O8, an estimated 32% increase from expected 2024 demand of 192 million pounds U3O8.

Primary Uranium Supply

On the supply side, uranium production for 2024 is estimated at 153 million pounds U3O8, which represents a 7% increase over 2023 production levels, largely due to the ramp-up of the McArthur River mine in Canada and Budenovskoye 6 and 7 in Kazakhstan. Taken together with UxC estimates of total demand for 2024, there is a significant primary supply shortfall estimated to be approximately 20% of total demand or 39 million pounds U3O8.

In Q4’2024, UxC estimated 2025 primary production to increase to 170 million pounds U3O8, with the production increase being supported by increasing production from Kazatomprom in Kazakhstan and the ramp-up of a series of mines in the United States and Africa. Additionally, UxC estimates secondary supplies for 2025 are projected at 25 million pounds of U3O8 equivalent (“U3O8e”), which is a significant reduction from 38 million pounds U3O8e of secondary supplies estimated in 2024, 61 million pounds U3O8e in 2023, and 69 million pounds U3O8e in 2022. Strong demand in past years has accelerated the process of drawing down these secondary sources of supply. With this rapid decline in secondary supplies, the market is expected to continue its shift from an inventory-driven market to a production-driven market in the coming years.

Nuclear sentiment also continues to be supported by an increased focus on energy security in the aftermath of Russia’s invasion of Ukraine. Additionally, the importance of security of supply was further magnified in July of 2023, as a military coup was waged in Niger, which led to the withdrawal of foreign embassy personnel, and an expropriation of Orano’s uranium mining operations in June 2024. In 2022, Niger ranked as the seventh largest uranium-producing country. The Russian invasion of Ukraine in February 2022 continues to cause significant turmoil in the global nuclear fuel market. Russia is a significant supplier of enriched uranium to the rest of the world, operating over 40% of the world’s uranium enrichment capacity prior to the Ukraine invasion. In 2021, Russian enrichment comprised 31% of European Union enrichment purchases and 28% of US utility enrichment purchases. While deliveries of material from Russia to Western utilities continue, increased demand for non-Russian supply has led to significantly increased prices for uranium processing services.

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From December 2021 to December 2024, the long-term price of conversion and enrichment services increased by 178% and 172%, respectively. In the short- to medium-term, in order to increase enriched uranium production in the supply-constrained Western enrichment market, Western enrichers are expected to input more UF6 (overfeed) into their centrifuges in order to maximize production capacity. As a consequence, Western utilities, in aggregate, would require more natural uranium feedstock to produce the same quantity of enriched uranium (i.e., enrichment contracts contain higher tails assay levels).

In 2023, US and European utilities demonstrated a path towards reduced reliance on Russian nuclear fuel supply and increasingly favouring Western supply chains. In December 2023, a US bill to curb imports of Russian uranium was approved by US Congress. In May 2024, the U.S. President signed law H.R. 1042, the Prohibiting Russia Uranium Imports Act, which prohibits the importation into the U.S. of low enriched uranium produced in the Russian Federations or by a Russian entity. This law includes a waiver provision to allow for imports if the U.S. Secretary of Energy determines no alternative source can be procured or if shipments are deemed in the national interest. This law reinforces the ongoing shift of Western uranium supply chains away from Russia, which increasingly favours North American uranium supply.

Russia is also a major player in uranium logistics, with significant quantities of uranium from Central Asia typically transported through Russia to Russian ports for delivery to Western uranium conversion facilities. UxC estimates Kazakhstan and Uzbekistan combined for 45% of global primary uranium production in 2024. As a result, logistics of uranium shipped through Russia remains an item of concern to uranium end users. Some uranium has been successfully shipped from Kazakhstan to Canada via the Trans-Caspian International Transport Route, which does not include transit through Russia; however, reports indicate that this route is subject to operational limitations.

Outlook

Overall, nuclear demand growth appears poised for acceleration led by a shifting energy mix towards decarbonized energy at a time when limited investment in bringing new uranium mine supply online has occurred over the past decade. While some idled or curtailed production from existing uranium mining operations has returned to the market, it is expected that (i) production costs associated with further potential restart projects will be higher than previous levels due to inflation and other restart challenges, and (ii) much of the potential new or greenfield mine supply required to meet demand estimates remains several years away.

The accelerated decline in secondary sources of uranium supply in recent years, the depletion of existing mines, the increase in tails assay at Western enrichment plants, and growing future reactor demand, point to larger supply deficits during the second half of this decade that may prove difficult to balance without considerable and rapid investment in new large-scale uranium mining projects. Uncovered utility uranium requirements for the period from 2024 to 2040, not including typical inventory building or restriction on existing supply agreements with Russia, are estimated at 2.1 billion pounds U3O8. It is therefore evident that the necessary new future sources of supply required by the market have not yet been secured by utilities, and that the response from incumbent suppliers to sign significant long-term supply contracts in recent years have not satisfied the needs of utility customers. Together, there is indication of a good reason to expect a further phase of utility procurement directed at incentivizing new projects to meet long-term demand needs.

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Competition

The uranium industry is small compared to other commodity or energy industries. Uranium demand is international in scope, but supply is characterized by a relatively small number of companies operating in only a few countries. Primary uranium production is concentrated amongst a limited number of producers and is also geographically concentrated, with 82% of the world’s production in 2024 projected to come from only four countries: Kazakhstan, Canada, Namibia, and Australia. Producers compete for market share and commercial terms necessary to support project economics. This is complicated by the influence of state-owned enterprises that operate within the uranium mining industry, often producing uranium supply as part of a vertical integration strategy that may be less sensitive to uranium pricing than those operating uranium mines as a primary business.

Competition is somewhat different amongst exploration & development companies focused on the discovery or development of a uranium deposit. Exploration for uranium is being carried out on various continents, but in recent years development activities by public companies have been generally concentrated in Canada, Africa, Australia, and the United States. In Canada, exploration has focused on the Athabasca Basin region in northern Saskatchewan. Explorers have been drawn to this area by the high-grade uranium deposits that have produced some of the most successful uranium mining operations in recent history. Within the Athabasca Basin region, exploration is generally divided between activity that is occurring in the eastern portion of the Basin and the western portion of the Basin. The eastern portion of the Basin is a district that is defined by rich infrastructure associated with existing uranium mines and uranium processing facilities. Infrastructure includes access to the provincial power grid and a network of all-weather provincial highways. By comparison, there are no uranium mines or processing facilities in the western portion of the Basin, and access to the provincial power grid is not currently available. Several uranium discoveries have been made in the Athabasca Basin region in recent years, and competition for capital, high-quality properties, and professional staff can be intense.

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Mineral Reserves and Mineral Resources

NI 43-101 requires mining companies to disclose mineral reserve and resource estimates using the subcategories of proven mineral reserves, probable mineral reserves, measured mineral resources, indicated mineral resources and inferred mineral resources.

Chad Sorba, P.Geo, Denison’s Vice President Technical Services and Project Evaluation, is a “Qualified Person” in accordance with the requirements of NI 43-101, and has reviewed and approved all disclosure of scientific or technical information in this AIF.

Denison Mineral Reserves and Mineral Resources

The following tables show the Company’s current estimates of mineral reserves and mineral resources as at December 31, 2024. For more information about the Company’s properties, see “Wheeler River” and “Other Exploration & Evaluation Projects”.

Proven Mineral Reserve Estimates (1,13)

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Probable Mineral Reserve Estimates (1,2,3,4,13)

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Measured Mineral Resource Estimates (1,5,7,13)

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Indicated Mineral Resource Estimates (1,5,7,13)

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Inferred Mineral Resource Estimates (1,6,13)

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Historical Estimates

A qualified person has not done sufficient work to verify and classify these historical estimates as current mineral resources for the Company or confirm their reporting of resources is in accordance with NI 43-101 categories, though the Company has no reason to believe the information is not relevant or reliable. The Company is not treating this information as current mineral resources. As these do not represent material properties for the Company at this time, the Company does not currently have any plans to conduct work to verify the historical estimates.

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JCU Estimates

Historical Indicated Mineral Resource Estimates (13)

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Historical Inferred Mineral Resource Estimates (13)

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McClean South

McClean South Historical Estimates (14)

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Notes to Mineral Resource and Mineral Reserve & Historical Estimates Tables:

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The summary information on Denison’s proven mineral reserve estimate for McClean was prepared from the year-end stockpile survey reported by Orano Canada, the MLJV operator.

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Mineral Properties – Athabasca Basin

Denison’s mineral property interests are primarily located in the Athabasca Basin region of northern Saskatchewan, the majority of which are located in the eastern portion of the Athabasca Basin, which is host to considerable existing infrastructure including uranium mines and mills, and provincial powerlines and highways (see location map, below). As at December 31, 2024, Denison has direct interests in 35 mineral properties in the Athabasca Basin, comprised of 227 claims covering approximately 385,000 hectares. Denison holds additional indirect interests in various uranium project joint ventures in Canada through its 50% ownership interest in JCU. Denison also holds an earn-in option to acquire an interest in the KLP from Grounded Lithium.

Location Map of Denison’s Athabasca Basin Mineral Properties

Athabasca Basin Overview

The Athabasca Basin covers an area of approximately 100,000 square kilometres in northern Saskatchewan and northeastern Alberta. The Athabasca Basin is one of the principal uranium-producing districts in the world and is host to the world’s highest-grade and some of the world’s largest uranium mines and deposits, including the McArthur River mine and Cigar Lake mine located in the eastern Athabasca Basin.

The uranium deposits are classified as unconformity-associated (also unconformity-related and –type) deposits owing to their spatial association with a major unconformable contact between a relatively undeformed Proterozoic sedimentary basin (the Athabasca Basin) and underlying metamorphosed and deformed Archean to Palaeoproerozoic basement rocks.

A broad variety of unconformity-associated deposit shapes, sizes, and compositions have been discovered. Two distinct varieties have been classified; 1) ‘egress-style’ polymetallic lenses at and above the unconformity, with variable and often highly elevated base metal and rare earth elements (“REE”) contents, and 2) ‘ingress-style’ vein sets within basement rocks, with typically lower base metal and REE contents.

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Egress-style deposits can occur in the sandstone, directly above the unconformity (e.g., Cigar Lake, Sue A and B), straddling the unconformity (e.g., Phoenix, Collins Bay B Zone, Midwest Main, Midwest A, McClean North, Key Lake) or perched high above the unconformity (certain zones at McClean Lake, Midwest, Cigar Lake). Ingress-style deposits are located in the basement rocks (e.g., Gryphon, Huskie, Eagle Point, Sue C, Sue E, Millennium, Arrow, Triple R); however, the Millennium deposit and, to an extent, the Gryphon deposit also contain subordinate mineralization at and above the unconformity. The Shea Creek deposits contain mineralization in the basement, deep in the basement, at the unconformity, and perched in the sandstone. In some deposits, there is a plunge to the mineralized pods from sandstone-hosted to basement-hosted within deposit–scale strike lengths (e.g., the Rabbit Lake-Collins Bay-Eagle Point trend, Sue trend deposits, McClean North).

The Athabasca unconformity-associated deposits are typically related to graphite-bearing structural zones within the metamorphosed and deformed Archean to Palaeoproerozoic basement rocks, which are often termed ‘corridors’ or ‘trends’. Alteration ‘halos’ or ‘envelopes’ tend to surround the mineralization, most notably in the overlying sandstone, and provide an enlarged exploration target through the detection of diagnostic alteration clays and geochemical pathfinder elements. Empirical exploration for the deposits typically involves mapping of structural corridors/trends by geophysical methods (dominantly electromagnetics, resistivity, or magnetics), followed by drill testing, given the buried or blind nature of the deposits below glacial cover or Athabasca sandstone, respectively. Drill core is subject to a variety of sampling and analytical methods to determine possible vectors toward mineralization, and downhole surveying is commonplace to test for elevated radioactivity or reconcile geophysical responses. The significant number of Athabasca uranium discoveries to date has also led to the development of numerous exploration models which are commonly used to facilitate interpretations and prioritize target areas.

Historical uranium production in the Athabasca Basin region used conventional open pit mining methods, such as the operations at Rabbit Lake, Cluff Lake, Key Lake and McClean Lake. Later in the mine life of Cluff Lake and Rabbit Lake, there was a transition to underground mining of other deposits on those properties.

The discovery of high-grade deposits such as Midwest, McArthur River and Cigar Lake in the 1980s did not immediately lead to production. The combination of challenging ground conditions (most notably the friable and water-saturated Athabasca sandstone conditions above the mineralization), depth, and the high-grade nature of the deposits required extensive research and development to design safe extraction methods before production was possible. Production from McArthur was achieved in the early 2000s, while Cigar Lake only initiated production in 2014. Production from these mines was only made possible by their unique combination of high grades (average grades > 10% U3O8) and large scale (>300 million lbs U3O8), as well as the development of innovative mining techniques, including ground freezing combined with either raise-bore mining or the use of the jet-boring mining system (“JBS”). The Midwest deposits are smaller in size than McArthur River and Cigar Lake, and remain undeveloped.

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In terms of mineral processing, each historical mining operation included a dedicated processing plant: Cluff Lake, Key Lake, Rabbit Lake and McClean Lake operations included on-site processing plants. Due to the rising cost of construction for such facilities and the availability of highways and other infrastructure in Saskatchewan’s North, processing of ores has transitioned to toll milling at existing facilities. McArthur River ore production is toll milled at the Key Lake mill, while Cigar Lake production is toll milled at the McClean Lake mill. With the suspension of operations at Rabbit Lake in 2016 and McArthur River in 2018, in part due to a prolonged slump in the global uranium market, only the Cigar Lake mine and the McClean Lake mill continued to operate and produce yellowcake in Saskatchewan during 2021.

In response to the COVID-19 pandemic, the Cigar Lake Joint Venture, operated by Cameco Corporation (“Cameco”), temporarily suspended production at the Cigar Lake mine from the end of March 2020 until September 2020, and then again from the end of December 2020 until April 2021. Coordinated therewith, the MLJV suspended operations at the McClean Mill for the duration of the suspended production.

In February 2022, Cameco announced its intention to restart uranium production at its McArthur River uranium mine and Key Lake uranium mill in 2022 — while at the same time outlining its intention to, together with Orano, continue to limit overall production at McArthur River and Cigar Lake well below full production rates. In February 2023, Cameco announced that due to improved uranium market conditions, Cigar Lake will instead target operating at its licensed capacity of 18 million pounds U3O8 and the plan will be for McArthur River to increase production to 18 million pounds U3O8 per year starting in 2024. Cameco announced that in 2024 it produced 16.9 million pounds U3O8 at Cigar Lake (due to a lower production rate at the McClean Lake Mill) and 20.3 million pounds U3O8 at McArthur River and Key Lake (setting a production record).

In January 2024, Denison and Orano Canada announced that the MLJV has approved a restart of uranium mining operations using the joint venture’s patented SABRE mining method. Mining is planned to commence at the McClean North deposit in 2025. See “Denison’s Operations-SABRE Mining Program” for further details.

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Wheeler River

Wheeler River, Denison’s material project, is the largest undeveloped uranium project in the infrastructure-rich eastern portion of the Athabasca Basin region, in northern Saskatchewan. The project is host to the high-grade Phoenix and Gryphon uranium deposits, discovered by Denison in 2008 and 2014, respectively. The Wheeler River Joint Venture participants are Denison (90%) and JCU (10%). Denison is the operator/manager of the project.

In June 2023, Denison announced the results of (i) the Phoenix FS completed for ISR mining of the high-grade Phoenix deposit and (ii) the Gryphon PFS Update for conventional underground mining of the basement-hosted Gryphon deposit.

The results of the Phoenix FS and Gryphon PFS Update were summarized in the technical report entitled “NI 43-101 Technical Report on the Wheeler River Project, Athabasca Basin, Saskatchewan, Canada”, filed on August 9, 2023, with an effective date of June 23, 2023 (the “Wheeler Report”), authored by David Myers P.Eng., Lorne Schwartz P.Eng., and Paul O’Hara P.Eng. of Wood; Gordon Graham P.Eng. of Engcomp Engineering and Computing Professionals Inc. (“Engcomp”), Mark Hatton P.Eng. of Stantec Consulting Ltd., Dan Johnson P.E., RM SME, then of WSP USA Environment and Infrastructure Inc., Gregory Newman P.Eng. of Newmans Geotechnique Inc., Jeffrey Martin P.Eng. of Ecometrix Incorporated, Mark Mathisen C.P.G. SLR International Corporation (“SLR”), William McCombe P.Eng. of Hatch Ltd., Cliff Revering P.Eng. of SRK Consulting (Canada) Inc. (“SRK”), and Geoffrey Wilkie P.Eng. of CanCost Consulting Inc.. The Wheeler Report is available on the Company’s website, under its profile on the SEDAR+ website at www.sedarplus.ca and on EDGAR at www.sec.gov/edgar.shtml.

The Phoenix FS reflects several design changes and the results of a rigorous technical de-risking program completed by Denison following the publication of the 2018 PFS and confirms robust economics and the technical viability of an ISR uranium mining operation with low initial capital costs and a high rate of return. Highlights of the Phoenix FS include:

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