An anonymous director reports

DENISON ANNOUNCES US$55 MILLION BOUGHT DEAL OFFERING

Denison Mines Corp. has entered into an agreement with Cantor Fitzgerald Canada Corp. as sole book-runner and lead underwriter on its own behalf and on behalf of a syndicate of underwriters, under which the underwriters have agreed to purchase, on a bought deal basis, 37 million shares of the company at $1.49 (U.S.) per share for aggregate gross proceeds of approximately $55.13-million (U.S.).

In addition, Denison has agreed to grant to the underwriters an overallotment option exercisable, in whole or in part, at the sole discretion of the underwriters to purchase up to an additional 5.55 million shares of the company at the issue price until Oct. 16, 2023, for potential additional gross proceeds to Denison of up to approximately $8.27-million (U.S.).

Denison intends to use the net proceeds from the offering to finance: (1) the advancement of the proposed Phoenix in situ recovery uranium mining operation at Denison's Wheeler River project through the procurement of long-lead items (including associated engineering, testing and design) identified during the continuing front-end engineering design process and the Phoenix feasibility study; (2) exploration and evaluation expenditures; and (3) general corporate and administrative expenses, including those in support of corporate development activities and working capital requirements.

Based upon preliminary budgets and plans, Denison expects the funds, taken together with existing financial resources, including those from prior prospectus financings, will be sufficient to advance the Phoenix project to a final investment decision and into the project execution phase. Denison further expects to be able to finance operations during this period while maintaining a large portion of its current physical uranium holdings to be utilized in the future in connection with financing the continued advancement and/or construction of the Phoenix project.

Denison will pay to the underwriters a cash commission equal to 4.75 per cent of the gross proceeds of the offering, including any proceeds received from the exercise of the overallotment option.

The offering will be made by way of a prospectus supplement to the company's existing Canadian short form base shelf prospectus and U.S. registration statement on Form F-10, as amended (file No. 333-258939), each dated Sept. 16, 2021. The registration statement was declared effective by the U.S. Securities and Exchange Commission on Sept. 17, 2021. The prospectus supplement has been filed with the securities commissions in each of the provinces and territories of Canada, except Quebec, and with the SEC. The Canadian prospectus supplement is available on the SEDAR+ website maintained by the Canadian Securities Administrators. The U.S. prospectus supplement (together with the related U.S. base shelf prospectus) is available on the SEC's website. Alternatively, the prospectus supplement may be obtained upon request by contacting the company or Cantor Fitzgerald Canada in Canada, attention: equity capital markets, 181 University Ave., Suite 1500, Toronto, Ont., M5H 3M7, e-mail: ecmcanada@cantor.com, or Cantor Fitzgerald, attention: equity capital markets, 499 Park Ave., sixth floor, New York, N.Y., 10022, or by e-mail at prospectus@cantor.com.

The offering is expected to close on or about Oct. 16, 2023, subject to the satisfaction of certain conditions, including, but not limited to, the receipt of all necessary approvals, including the approval of the Toronto Stock Exchange and the NYSE American.

About Denison Mines Corp.

Denison is a uranium exploration and development company with interests focused in the Athabasca basin region of Northern Saskatchewan, Canada. In addition to the company's effective 95-per-cent interest in its flagship Wheeler River uranium project, Denison's interests in Saskatchewan include a 22.5-per-cent ownership interest in the McClean Lake joint venture, which comprises several uranium deposits and the McClean Lake uranium mill that is contracted to process the ore from the Cigar Lake mine under a toll milling agreement, plus a 25.17-per-cent interest in the Midwest Main and Midwest A deposits and a 67.41-per-cent interest in the Tthe Heldeth Tue 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.

Through its 50-per-cent ownership of JCU, Denison holds additional interests in various uranium project joint ventures in Canada, including the Millennium project (JCU, 30.099 per cent), the Kiggavik project (JCU, 33.8118 per cent) and Christie Lake (JCU, 34.4508 per cent).

Denison's exploration portfolio includes further interests in properties covering approximately 285,000 hectares in the Athabasca basin region.

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