Denison Announces Closing of Transaction with Skyharbour and Formation of Four Prospective Exploration Joint Ventures Proximal to Wheeler River

Rhea-AI Summary

Denison (NYSE: DNN) closed a transaction with Skyharbour and formed four exploration joint ventures on claims from Skyharbour's Russell Lake project located adjacent to Denison's Wheeler River.

Key terms: Denison will be operator and hold 49% of Wheeler North and 70% of Wheeler River Inliers; Denison holds 20% of Russell Lake and 30% of Getty East where Skyharbour will be operator. Denison has option agreements to increase its interest in Wheeler North and Getty East to up to 70%.

The announcement notes prior regulatory milestones for Wheeler River: provincial EA approval in July 2025 and conclusion of the CNSC public hearing in December 2025.

Positive

• Formed 4 joint ventures on claims adjacent to Wheeler River
• Denison to operate Wheeler North with a 49% interest
• Denison holds 70% of Wheeler River Inliers (operator)
• Earn-in options to increase ownership to up to 70% in two JVs

Negative

• None.

Key Figures

Wheeler North JV interest 49% Initial Denison ownership in Wheeler North joint venture

Wheeler River Inliers JV interest 70% Initial Denison ownership in Wheeler River Inliers joint venture

Russell Lake JV interest 20% Denison ownership in Russell Lake joint venture operated by Skyharbour

Getty East JV interest 30% Denison ownership in Getty East joint venture operated by Skyharbour

Earn-in cap 70% Maximum ownership Denison can earn in Wheeler North and Getty East JVs

Wheeler River interest 95% Denison’s effective interest in flagship Wheeler River Uranium Project

Athabasca land package ~457,000 hectares Denison’s direct ownership interests in Athabasca Basin properties

Skyharbour projects 37 projects / 616,000 hectares Skyharbour uranium exploration portfolio in Athabasca Basin

Market Reality Check

$2.48 Last Close

Volume Volume 38,178,583 vs 20-day avg 48,090,110 (relative volume 0.79x). normal

Technical Price $2.60 is trading above 200-day MA at $2.06 ahead of this JV closing.

Peers on Argus

Uranium peers were mixed: UUUU (+5.39%) and LEU (+5.94%) rose, while NXE (-1.29%) and UEC (-0.9%) fell, suggesting stock-specific factors around Denison’s JV closing.

Historical Context

Date	Event	Sentiment	Move	Catalyst
Dec 04	Community agreement	Positive	+5.2%	Impact Benefit and Exploration Agreements supporting Wheeler River development and exploration.
Dec 01	Community agreement	Positive	-1.6%	Nuhenéné Benefit Agreement granting consent and support for key Saskatchewan projects.
Nov 17	Strategic JV deal	Positive	-3.6%	Agreements with Skyharbour to acquire initial Russell Lake joint venture interests.
Nov 06	Earnings and ops	Positive	-4.1%	Q3 2025 results, first McClean North production, financing and progress at Phoenix ISR.
Nov 04	Legal challenge	Negative	-6.2%	Judicial review application seeking to set aside provincial EA approval for Wheeler River.

Pattern Detected

Operational and strategic positives have often seen muted or negative next-day moves, while clearly adverse legal headlines have aligned with declines.

Recent Company History

Over the last several months, Denison has advanced both community agreements and strategic positioning around Wheeler River. On Nov 17, 2025, it announced agreements with Skyharbour to secure initial Russell Lake joint venture interests. Subsequent benefit and impact agreements with regional Indigenous and municipal partners on Dec 1 and Dec 4, 2025 reinforced support for Wheeler River and related projects. However, a Nov 4, 2025 judicial review application challenged provincial EA approval. Today’s closing of the Skyharbour transaction builds directly on the prior JV framework.

Market Pulse Summary

This announcement confirms closing of the Skyharbour transaction and formalizes four joint ventures surrounding Wheeler River, with Denison operating two and holding interests of up to 70% in key blocks. It builds on earlier agreements disclosed on Nov 17, 2025 and complements recent community benefit arrangements and permitting milestones. Investors may watch how exploration spending, earn-in progress, and federal approvals for the Phoenix ISR project evolve alongside these expanded land positions.

Key Terms

joint ventures financial

"formation of four joint ventures consisting of claims previously comprising"

A joint venture is a business arrangement where two or more companies come together to work on a specific project or goal, sharing both the risks and the rewards. It’s like partners teaming up for a common goal, which can help them access new markets, share expertise, or reduce costs. For investors, joint ventures can create new opportunities but also involve shared responsibilities and potential risks.

pre-feasibility study technical

"an update to the previously prepared 2018 Pre-Feasibility Study ('PFS') was completed"

A pre-feasibility study is an initial assessment that evaluates whether a proposed project or investment idea is worth exploring further. It involves examining basic factors like costs, potential benefits, and possible challenges, similar to conducting a preliminary check before deciding to invest more time and resources. This helps investors determine if pursuing the project further is practical and likely to be successful.

environmental assessment regulatory

"approval in July 2025 of the project's EA by the Province of Saskatchewan"

An environmental assessment is a process that evaluates how a project or activity might impact the natural surroundings, such as air, water, land, and wildlife. It helps identify potential environmental risks and ensures that any negative effects are managed or minimized. For investors, this assessment provides insight into the sustainability and long-term viability of projects, which can influence their financial decisions and risk management.

canadian nuclear safety commission regulatory

"conclusion in December 2025 of the Canadian Nuclear Safety Commission Public Hearing"

The Canadian Nuclear Safety Commission is the federal regulator that oversees the safety and security of nuclear energy and radioactive materials in Canada, setting rules, issuing licences, and inspecting facilities. Its decisions affect project timelines, operating costs and legal risk for companies in the nuclear, energy and medical isotope sectors—like a building inspector whose approval determines whether a project can open or must fix costly problems, so investors watch it closely.

toll milling agreement financial

"McClean Lake uranium mill ... under a toll milling agreement"

A toll milling agreement is a contract where one company pays a processor to grind, mill or otherwise transform its raw materials into finished or semi‑finished products while the material owner keeps legal title and pays a fee for the service. For investors it matters because it lets a business avoid buying expensive production plants, affecting costs, margins, supply‑chain risk and operational flexibility—like renting a specialized workshop instead of owning it.

in-situ recovery technical

"Phoenix feasibility study was completed for the Phoenix deposit as an ISR mining operation"

In-situ recovery is a mining method that extracts a valuable material by dissolving it underground and pumping the solution to the surface instead of digging or blasting rock. For investors, it matters because this approach often lowers upfront construction costs, shortens development time and reduces visible land disturbance, but it also brings regulatory, environmental and groundwater risks that can affect project timelines, operating costs and valuation.

AI-generated analysis. Not financial advice.

TORONTO, Dec. 17, 2025 /PRNewswire/ - Denison Mines Corp. ("Denison" or the "Company") (TSX: DML; NYSE American: DNN) is pleased to announce that it has closed the previously announced transaction (the "Transaction") with Skyharbour Resources Ltd. ("Skyharbour") (TSX-V:SYH) (OTCQX: SYHBF), (Frankfurt:SC1P) and the formation of four joint ventures consisting of claims previously comprising Skyharbour's Russell Lake Uranium Project ("Russell"), which is located directly adjacent to Denison's flagship Wheeler River Project ("Wheeler River"). View PDF Version.

The new joint ventures are designed to drive collaboration between Denison and Skyharbour's technical teams and to accelerate the evaluation of the prospective exploration ground adjacent to and proximal to Wheeler River.  Denison will serve as the operator for the Wheeler North and Wheeler River Inliers joint ventures, with ownership interests of 49% and 70% respectively.  Skyharbour will serve as the operator for the Russell Lake (or "RL") and Getty East joint ventures, with Denison having ownership interests of 20% and 30%, respectively. 

In addition, Denison and Skyharbour have entered into option agreements (the "Earn-In Option Agreements"), which allow Denison to increase its ownership interest in each of the Wheeler North and Getty East joint ventures to up to 70%.

About Denison

Denison is a leading uranium mining, development, and exploration company with interests focused in the Athabasca Basin region of northern Saskatchewan, Canada. Denison has an effective 95% interest in its flagship Wheeler River Uranium Project, which is the largest undeveloped uranium project in the infrastructure rich eastern portion of the Athabasca Basin region of northern Saskatchewan.

In mid-2023, the Phoenix feasibility study was completed for the Phoenix deposit as an ISR mining operation, and an update to the previously prepared 2018 Pre-Feasibility Study ('PFS') was completed for Wheeler River's Gryphon deposit as a conventional underground mining operation. Based on the respective studies, both deposits have the potential to be competitive with the lowest cost uranium mining operations in the world. Permitting efforts for the planned Phoenix ISR operation commenced in 2019 and are nearing completion with approval in July 2025 of the project's EA by the Province of Saskatchewan and conclusion in December 2025 of the Canadian Nuclear Safety Commission Public Hearing for Federal approval of the EA and project construction license.

Denison's interests in Saskatchewan also include a 22.5% ownership interest in the McClean Lake Joint Venture ('MLJV'), which includes unmined uranium deposits (with mining at McClean North deposit via the MLJV's SABRE mining method having commenced in July 2025 using the MLJV's SABRE mining method) and the McClean Lake uranium mill (currently utilizing a portion of its licensed capacity to process the ore from the Cigar Lake mine under a toll milling agreement), plus a 25.17% interest in the Midwest Joint Venture Midwest Main and Midwest A deposits, and a 70.55% interest in the Tthe Heldeth Túé ('THT') and Huskie deposits on the Waterbury Lake Property. The Midwest Main, Midwest A, THT and Huskie deposits are located within 20 kilometres of the McClean Lake mill. Taken together, Denison has direct ownership interests in properties covering ~457,000 hectares in the Athabasca Basin region.

Additionally, through its 50% ownership of JCU (Canada) Exploration Company, Limited ('JCU'), Denison holds interests in various uranium project joint ventures in Canada, including the Millennium project (JCU, 30.099%), the Kiggavik project (JCU, 33.8118%) and Christie Lake (JCU, 34.4508%).

In 2024, Denison celebrated its 70th year in uranium mining, exploration, and development, which began in 1954 with Denison's first acquisition of mining claims in the Elliot Lake region of northern Ontario.

About Skyharbour

Skyharbour holds an extensive portfolio of uranium exploration projects in Canada's Athabasca Basin and is well positioned to benefit from improving uranium market fundamentals with interest in thirty-seven projects covering over 616,000 hectares (over 1.5 million acres) of land. Skyharbour has acquired from Denison, a large strategic shareholder of Skyharbour, a 100% interest in the Moore Uranium Project, which is located 15 kilometres east of Denison's Wheeler River project and 39 kilometres south of Cameco's McArthur River uranium mine. Moore is an advanced-stage uranium exploration property with high-grade uranium mineralization in several zones at the Maverick Corridor. Adjacent to the Moore Project is the Russell Lake Uranium Project, which hosts widespread uranium mineralization in drill intercepts over a large property area with exploration upside potential. Skyharbour is actively advancing these projects through exploration and drilling programs.

Skyharbour also has joint ventures with industry leaders Denison, Orano Canada Inc., Azincourt Energy, and Thunderbird Resources at the Russell, Preston, East Preston, and Hook Lake Projects, respectively. Skyharbour also has several active earn-in option partners, including CSE-listed Basin Uranium Corp. at the Mann Lake Uranium Project; TSX-V listed North Shore Uranium at the Falcon Project; UraEx Resources at the South Dufferin and Bolt Projects; Hatchet Uranium at the Highway Project; CSE-listed Mustang Energy at the 914W Project; and TSX-V listed Terra Clean Energy at the South Falcon East Project.

Cautionary Statement Regarding Forward-Looking Statements

Certain information contained in this news release constitutes 'forward-looking information', within the meaning of the applicable United States and Canadian legislation, concerning the business, operations and financial performance and condition of Denison.  Generally, these forward-looking statements can be identified by the use of forward-looking terminology such as 'potential', 'plans', 'expects', 'budget', 'scheduled', 'estimates', 'forecasts', 'intends', 'anticipates', or 'believes', or the negatives and/or variations of such words and phrases, or state that certain actions, events or results 'may', 'could', 'would', 'might' or 'will' 'be taken', 'occur' or 'be achieved'.

In particular, this news release contains forward-looking information pertaining to Denison's current intentions, objectives and commitments with respect to the Transaction and the expected benefits thereof; the Company's exploration, development and expansion plans and objectives; and expectations regarding its joint venture ownership interests and the continuity of its agreements with its partners and third parties.

Forward looking statements are based on the opinions and estimates of management as of the date such statements are made, and they are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of Denison to be materially different from those expressed or implied by such forward-looking statements. For example, the parties to the Option Agreement may not complete the option phases as described and/or the exploration objectives may not be achieved.  In addition, Denison may decide or otherwise be required to discontinue testing, evaluation and other work on the Company's other properties if it is unable to maintain or otherwise secure the necessary resources (such as testing facilities, capital funding, joint venture approvals, regulatory approvals, etc.).  Denison believes that the expectations reflected in this forward-looking information are reasonable but no assurance can be given that these expectations will prove to be accurate and results may differ materially from those anticipated in this forward-looking information. For a discussion in respect of risks and other factors that could influence forward-looking events, please refer to the factors discussed in Denison's Annual Information Form dated March 28, 2025 under the heading 'Risk Factors' or in subsequent quarterly financial reports. These factors are not, and should not be construed as being, exhaustive.

Accordingly, readers should not place undue reliance on forward-looking statements. The forward-looking information contained in this news release is expressly qualified by this cautionary statement. Any forward-looking information and the assumptions made with respect thereto speaks only as of the date of this news release. Denison does not undertake any obligation to publicly update or revise any forward-looking information after the date of this news release to conform such information to actual results or to changes in Denison's expectations except as otherwise required by applicable legislation.

 

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SOURCE Denison Mines Corp.

FAQ

What joint ventures did Denison and Skyharbour form related to Wheeler River (DNN)?

They formed four JVs: Wheeler North, Wheeler River Inliers, Russell Lake (RL), and Getty East, using Skyharbour claims adjacent to Wheeler River.

What ownership stakes did Denison announce in the new JVs (DNN)?

Denison holds 49% of Wheeler North, 70% of Wheeler River Inliers, 20% of Russell Lake, and 30% of Getty East.

Can Denison increase its JV stakes in the Wheeler-area deals (DNN)?

Yes. Denison and Skyharbour entered earn-in option agreements allowing Denison to increase ownership in Wheeler North and Getty East to up to 70%.

Which parties will operate the new joint ventures near Wheeler River (DNN)?

Denison will operate Wheeler North and Wheeler River Inliers; Skyharbour will operate Russell Lake and Getty East.

What recent regulatory milestones for Wheeler River did Denison disclose (DNN)?

Denison noted provincial EA approval in July 2025 and conclusion of the CNSC public hearing for federal approvals in December 2025.

How do these JVs relate to Denison’s Wheeler River project (DNN)?

The JVs cover prospective exploration ground directly adjacent to and proximal to Denison's Wheeler River flagship project.