Sunshine Silver Mining closes IPO with full over-allotment exercise

Sunshine Silver Mining & Refining Announces Closing of Initial Public Offering, Including Full Exercise of Over-Allotment Option Sunshine Silver Mining & Refining Announces Closing of Initial Public Offering, Including Full Exercise of Over-Allotment Option PR Newswire KELLOGG, Idaho , June 5, 2026 /PRNewswire/ -- Sunshine Silver Mining & Refining Company (the "Company" or "Sunshine") today announced the closing of its initial public offering of 23,000,000 shares of common stock at a public offering price of $13.50 per share, including the full exercise by the underwriters of their option to purchase additional shares. The aggregate gross proceeds from the offering, before deducting underwriting discounts and commissions and other offering expenses were approximately $310.5 million. Sunshine's common stock began trading on the New York Stock Exchange on June 4, 2026, under the ticker symbol "SSMR." Morgan Stanley, Scotiabank and BMO Capital Markets acted as joint lead book-running managers for the offering.

Canaccord Genuity, Citigroup and RBC Capital Markets acted as joint bookrunners. A registration statement relating to these securities was declared effective by the Securities and Exchange Commission on June 3, 2026. A prospectus relating to and describing the terms of the offering has been filed with the Securities and Exchange Commission and is available on the SEC's website at www.sec.gov .   A copy of the prospectus may also be obtained from: Morgan Stanley & Co. LLC, Attention: Prospectus Department, 180 Varick Street, 2nd Floor, New York, New York 10014; Scotia Capital (USA) Inc., 250 Vesey Street, 24th Floor, New York, NY 10281, Attention: Equity Capital Markets, or by telephone at (212) 255-6854, or by email at   us.ecm@scotiabank.com; and BMO Capital Markets Corp., Attn: Equity Syndicate Department, 151 W 42nd Street, 32nd Floor, New York, NY 10036, or by email at   bmoprospectus@bmo.com.

This press release shall not constitute an offer to sell or the solicitation of an offer to buy these securities, nor shall there be any sale of these securities in any state or jurisdiction in which such an offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. About Sunshine Silver Mining & Refining Company The Company is dedicated to bringing the historic, permitted Sunshine Mine back into production. As the largest mineral rights holder in Idaho's Coeur d'Alene Mining District – the most prolific silver district in U.S. history – Sunshine benefits from favorable mining regulations, an existing skilled labor force, mine suppliers and strong support for mining from the local population and government.

The Sunshine Mine is one of the highest-grade primary silver resources in the world, and the Company is one of the few U.S.-based entities with a vertically integrated mine-to-mill-to-refinery platform, supported by a permitted onsite silver refinery and the major permits required for antimony production. Forward-Looking Statements This press release contains forward-looking statements, including statements regarding the Company's business strategy, the Company's plans and objectives for future operations and industry trends. These statements are not historical facts but rather are based on the Company's current expectations and projections regarding its business, operations and other factors relating thereto.