Mr. Keith Bodnarchuk reports

COSA RESOURCES EXECUTES AGREEMENT TO FORM JOINT VENTURES WITH DENISON MINES ON MULTIPLE URANIUM PROJECTS

Cosa Resources Corp. has entered into an acquisition agreement with Denison Mines Corp. Pursuant to the acquisition agreement, Cosa will acquire an interest in three of Denison's uranium exploration projects located in the eastern Athabasca basin.

Highlights:

• Cosa to acquire a 70-per-cent interest in a portfolio of Denison's prospective uranium projects located in the eastern Athabasca basin;
• Denison to become 19.95-per-cent shareholder of Cosa and commits to a minimum of $1-million participation in future equity financings;
• Cosa's senior management team is uniquely experienced to advance these mature, discovery-ready projects.

The projects consist of: (a) the Murphy Lake North project, located within four kilometres of IsoEnergy Ltd.'s Hurricane deposit; (b) the Darby project, located 10 kilometres west of Cameco's Cigar Lake mine; and (c) the Packrat project, located 19 kilometres southwest of the Rabbit Lake mill.

Keith Bodnarchuk, Cosa's president and chief executive officer, commented: "This is a transformational day for Cosa Resources by bringing in an industry-leading shareholder in Denison and adding three strategically selected, discovery-ready exploration projects to Cosa's Athabasca basin portfolio. All three projects offer tremendous upside potential for our shareholders. Most notably, Murphy Lake North is within four kilometres of and on trend with IsoEnergy's Hurricane deposit -- discovered in 2018 by Cosa's management team and currently the highest-grade indicated mineral resource for uranium on the planet at a staggering average grade of 34.5 per cent U3O8 [triuranium octoxide]. Cosa views this strategic collaboration with Denison as mutually beneficial, allowing Cosa to increase discovery potential while offering Denison exposure to Cosa's exploration success. Cosa remains committed to advancing priority target areas within our existing exploration portfolio, including the 100-per-cent-owned Ursa project, where we recently intersected multiple intervals of basement-hosted radioactivity. In this highly competitive uranium market, opportunities to acquire projects of this quality are rare. Opportunities to acquire these projects and bring in a supportive long-term shareholder of Denison's quality are almost non-existent. This transaction is expected to create a competitive advantage for Cosa and differentiate us from our peers. We look forward to closing this agreement and continuing to update the market with our remaining 2024 results and plans for 2025."

David Cates, Denison's president and chief executive officer, commented: "Denison is pleased to collaborate with Cosa in a way that is mutually beneficial and enhances our exposure to the potential discovery of a meaningful uranium deposit on the properties and through Cosa's existing and prospective uranium exploration portfolio. With Denison focused on executing on our core mining and development-stage projects, we believe Cosa is an excellent partner to advance exploration of the projects. The entire Cosa senior management team has worked with Denison previously and have strong technical capabilities plus a unique familiarity with the projects and nearby discoveries."

The projects

Murphy Lake North

Murphy Lake North covers a portion of the Larocque Lake trend and is located 3.2 kilometres east of the Hurricane deposit. The Hurricane deposit is the world's highest-grade indicated mineral resource for uranium and was discovered and delineated for IsoEnergy by current members of Cosa's management, board of directors and advisers from 2018 through 2022. The Larocque Lake trend also hosts the Larocque Lake zone, the Yelka prospect and the Alligator Lake zone. Murphy Lake North contains approximately six kilometres of conductive strike length oriented subparallel to conductive features associated with the Hurricane deposit. Limited historical drilling completed on Murphy Lake North intersected weak mineralization in the basement and zones of alteration and structure in the sandstone and basement. Historical drilling, completed prior to the discovery of Hurricane, focused on the western extremity of the property and left most of the conductive strike length untested. Abundant drill targets exist at Murphy Lake North and diamond drilling is planned for the first half of 2025.

The depth to the unconformity at Murphy Lake North is approximately 250 metres.

The Darby project

The Darby project is located 10 kilometres west of the Cigar Lake mine and 17 kilometres north of the McArthur River mine. Darby is interpreted to contain more than 25 kilometres of conductive strike length, including the eight-kilometre-long 95B trend oriented parallel to the Cigar Lake/Tucker Lake trend. Historical drilling on 95B defined more than 25 metres of unconformity offset where a package of metasedimentary rocks hosting graphitic brittle structure, hydrothermal alteration and weak uranium mineralization lies in fault contact with underlying granitic rocks. Only one drill hole completed along strike is interpreted to have intersected the optimal target in this prospective geological setting. Weak uranium mineralization has also been intersected in the northeast portion of Darby proximal to the Cigar Lake/Tucker Lake trend and along the northern extension of the 4A trend north of Darby. Initial work is expected to include diamond drilling to follow up historical drilling results and geophysical surveying to refine conductive drill targets.

The depth to the unconformity at Darby is between 480 and 650 metres.

The Packrat project

The Packrat project is located 28 kilometres east of the Cigar Lake mine and 19 kilometres southwest of the Rabbit Lake mill. Packrat covers a prominent magnetic break and basement-hosted resistivity-low trend lying along interpreted magnetic lineaments related to the Cigar Lake/Tucker Lake magnetic-low trend. Limited historical drilling on Packrat, which targeted the resistivity-low trend and magnetic break, intersected weak uranium mineralization and zones of structural disruption and alteration of basement rocks. Initial work at Packrat is expected to include compilation and reinterpretation of historical geophysical and drilling data.

The depth to the unconformity at Packrat is less than 100 metres.

Transaction summary

Under the terms of the acquisition agreement, Cosa will acquire a 70-per-cent interest in each of the projects from Denison. Upon closing of the transaction, the parties will enter into a joint venture on each of the projects. Cosa will initially be the operator for all joint ventures. In addition, Denison has agreed to participate in subsequent equity financings of Cosa for aggregate total proceeds of a minimum of $1-million.

As consideration for the transaction, Cosa will issue 14,195,506 common shares, equivalent to 19.95 per cent of the outstanding common shares of Cosa upon completion of the transaction.

Additionally, Cosa will be required to:

• Issue Denison a further $2.25-million in deferred consideration shares within a five-year period beginning at the closing date of the transaction;
• Finance 100 per cent of the first $1.5-million in exploration expenditures on the Murphy Lake North project by Dec. 31, 2027; failure to do so will result in Denison's ownership in the Murphy Lake North project reverting to 51 per cent and Denison will assume operatorship;
• Finance 100 per cent of the first $5-million in exploration expenditures on the Darby project by June 30, 2029; failure to do so will result in Denison's ownership in the Darby project reverting to 51 per cent and Denison will assume operatorship.

The Darby project is subject to a buydown, which permits Denison to reclaim up to 60 per cent of the Darby project and is to be the greater of: (i) $50-million; or (ii) 450 per cent of Cosa's exploration expenditures to date (excluding the initial $5-million in Cosa-financed expenditures) incurred on the Darby claim(s) for the proportion of the property interest subject to the buydown. The buydown can be completed through a combination of cash payments and Denison sole-financed work and must be a minimum of 25 per cent cash. The buydown will be extinguished if Denison's interest in the Darby project claims subject to the buydown fall below 10 per cent or upon commercial production of 500,000 pounds of U3O8 from the claims subject to the buydown. Cosa is to appoint a technical adviser nominated by Denison for a period of five years from the closing date or until all of Cosa's obligations under the acquisition agreement have been fulfilled.

The transaction is an arm's-length transaction under the policies of the TSX Venture Exchange. The transaction will constitute a reviewable transaction under the policies of the TSX-V. No finders' fees are expected to be paid by the company in connection with the transaction. The consideration shares and the deferred consideration shares will be subject to a statutory hold period of four months and one day from the date of issuance thereof. Trading of the company's common shares on the TSX-V is expected to remain halted, pending receipt and review of documentation relating to the transaction.

Completion of the transaction is subject to a number of conditions precedent, including, but not limited to: (i) acceptance by the TSX-V and receipt of other applicable regulatory approvals and (ii) certain other closing conditions customary for a transaction of this nature.

Upon completion of the transaction: (a) current shareholders of Cosa will hold approximately 80.05 per cent of the common shares; and (b) Denison will hold approximately 19.95 per cent of the outstanding common shares.

Ancillary agreements

In connection with closing of the transaction, Cosa and Denison will enter into a royalty agreement for each project, an investor rights agreement and a joint venture agreement for each project.

The royalty agreements will provide Denison with a 2-per-cent net smelter royalty (NSR) on the Darby and Packrat projects and a 0.5-per-cent NSR on the Murphy Lake North project. Cosa will have the right to repurchase 50 per cent of the royalties on the Darby project and the Packrat project in exchange for a cash payment of $2-million per project.

The investor rights agreement will provide, among other things, that, for so long as Denison holds at least 5 per cent of the issued and outstanding common shares, it will have a pre-emptive right and top-up rights entitling it to maintain and/or otherwise acquire up to a 19.95-per-cent interest in Cosa. Additionally, Denison will have the right to nominate one director to Cosa's board of directors for so long as Denison holds at least 5 per cent of the issued and outstanding common shares and an additional director to Cosa's board of directors for so long as Denison holds at least 10 per cent of the issued and outstanding common shares.

Pursuant to the joint venture agreements, the parties will form joint ventures, in which Cosa will have a 70-per-cent interest and Denison will have a 30-per-cent interest in each project as of the closing date.

The transaction is expected to be completed by early 2025.

About Cosa Resources Corp.

Cosa Resources is a Canadian uranium exploration company operating in Northern Saskatchewan. The portfolio comprises roughly 237,000 hectares across multiple 100-per-cent-owned-and-Cosa-operated joint venture projects in the Athabasca basin region, all of which are underexplored, and the majority reside within or adjacent to established uranium corridors.

Cosa's award-winning management team has a long record of success in Saskatchewan. In 2022, members of the Cosa team were awarded the AME Colin Spence Award for their previous involvement in discovering IsoEnergy's Hurricane deposit. Prior to Hurricane, Cosa personnel led teams or had integral roles in the discovery of Denison's Gryphon deposit and 92 Energy's Gemini zone and held key roles in the founding of both NexGen and IsoEnergy.

Cosa's primary focus through 2024 was initial drilling at the 100-per-cent-owned Ursa project, which captures over 60 kilometres of strike length of the Cable Bay shear zone, a regional structural corridor with known mineralization and limited historical drilling. It potentially represents the last remaining eastern Athabasca corridor to not yet yield a major discovery, which the company believes is primarily due to a lack of modern exploration. Modern geophysics completed by Cosa in 2023 identified multiple high-priority target areas characterized by conductive basement stratigraphy beneath or adjacent to broad zones of inferred sandstone alteration -- a setting that is typical of most eastern Athabasca uranium deposits. Guided by a recently completed ambient noise tomography (ANT) survey, Cosa's second and most recent drilling campaign at Ursa intersected a significant zone of unconformity-style sandstone-hosted structure and alteration underlain by several intervals of anomalous radioactivity in the basement rocks. Follow-up is currently in planning for 2025.

Qualified person

The company's disclosure of technical or scientific information in this press release has been reviewed and approved by Andy Carmichael, PGeo, vice-president, exploration, for Cosa. Mr. Carmichael is a qualified person as defined under the terms of National Instrument 43-101. This news release refers to neighbouring properties in which the company has no interest. Mineralization on those neighbouring properties does not necessarily indicate mineralization on the company's properties.

We seek Safe Harbor.