Mr. Keith Bodnarchuk reports

COSA RESOURCES ISSUES DEFERRED PAYMENT SHARES TO DENISON MINES

Cosa Resources Corp. has issued common shares to Denison Mines Corp. as full satisfaction of the deferred consideration pursuant to the acquisition agreement between Cosa and Denison.

Keith Bodnarchuk, president and chief executive officer, commented: "Working closely with Denison since January, 2025, has been incredibly rewarding for the company, and we are very pleased to continue to work with Denison as our largest shareholder and joint venture partner. Full satisfaction of the deferred consideration, combined with the recently completed $12-million bought deal financing, has left the company debt free and well financed through 2027. With an irrevocable 70-per-cent ownership in the Murphy Lake North joint venture and an ongoing drill program that is the largest in Cosa's history, we are excited for the future and thank Denison for their continued support and participation."

Deferred consideration shares

The company announces that it has issued an aggregate of 2,154,476 deferred consideration shares at a deemed price of 69.036 cents per share as full satisfaction of the deferred consideration per the acquisition agreement between Cosa and Denison dated Nov. 26, 2024. The deferred consideration shares are subject to a statutory hold period of four months and a day.

Denison will be filing an early warning report, under National Instrument 62-103, The Early Warning System and Related Take-Over Bid and Insider Reporting Issues, in respect of its acquisition of the 2,154,476 deferred consideration shares. Prior to the issuance of the deferred consideration shares by Cosa, Denison held 21,740,864 shares and 2,417,679 common share purchase warrants, representing 17.5 per cent of Cosa on a partially diluted basis. Immediately after giving effect to the issuance of the deferred consideration shares, Denison had beneficial ownership of, or control and direction over, 23,895,340 shares, representing 18.9 per cent of the issued and outstanding shares of Cosa on a partially diluted basis as of the date hereof and 2,417,679 common share purchase warrants, representing 13.5 per cent of Cosa's issued and outstanding warrants. The deferred consideration shares were acquired pursuant to Denison's rights under the acquisition agreement and held by Denison for investment purposes. Denison intends to review, on a continuous basis, various factors related to its investment in Cosa, and may decide to acquire or dispose of additional securities of Cosa as future circumstances may dictate, including pursuant to the exercise of warrants, the terms of the acquisition agreement, and/or its pre-emptive rights under the investor rights agreement between Denison and Cosa. Further information will be available in the early warning report to be filed by Denison under Cosa's profile on SEDAR+ or by contacting Denison, Geoff Smith, vice-president corporate development and commercial, Denison Mines, info@denisonmines.com, Suite 1100, 40 University Ave., Toronto, Ont., M5J 1T1.

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 underexplored 100-per-cent-owned and Cosa-operated joint venture projects in the Athabasca basin region, the majority of which reside within or adjacent to established uranium corridors.

In January of 2025, the company entered a transformative strategic collaboration with Denison Mines that has secured access to several additional highly prospective eastern Athabasca uranium exploration projects. As Cosa's largest shareholder, Denison gains exposure to Cosa's potential for exploration success and its pipeline of uranium projects.

The company's primary focus through the remainder of 2026 will be drilling at the Murphy Lake North and Darby projects in the eastern Athabasca basin. Drilling at Murphy Lake North will follow up uranium mineralization within an extensive zone of strong structure and hydrothermal alteration at the Cyclone trend. Drilling at Darby will follow up on intersections of anomalous geochemistry, structure and zones of hydrothermal alteration from both winter 2026 drilling and historical drilling.

Cosa's award-winning management team has a record of success in Saskatchewan. In 2022, members of the Cosa team were awarded the AME Colin Spence Award for the discovery of the Hurricane uranium deposit. Cosa personnel led teams or had integral roles in the discovery of Denison's Gryphon deposit, and held key roles in the founding of both NexGen and IsoEnergy.

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