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Altiplano Metals Inc.

250 Southridge NW, Suite 300

Edmonton, AB

Canada

T6H 4M9

47415910v1

Altiplano Provides an Additional Update on Legal Proceedings in Chile

EDMONTON AB, September 16th, 2026 - Altiplano Metals Inc. (TSXV: APN) (WKN: A2JNFG) ("Altiplano" or the "Company") provides an update on the legal actions initiated against two of the Company's wholly owned Chilean subsidiaries, Andes Metals SpA and Altiplano Minerals SpA. The Company and the Company's other subsidiaries are not subject to these initiated proceedings.

Altiplano confirms in both court cases that it has submitted its defense to each court. The Company's counsel attended the preliminary hearings, attended the evidentiary hearings, submitted the evidence in favor of the Company and submitted the objections to the evidence submitted by the plaintiff. Both liquidation requests are pending resolution. The final ruling in both cases is scheduled for September 23, 2026.

The Company confirms that is working with local stake holders and authorities to resolve the proceedings to prevent any further actions. The Company will provide an update once more information is available.

ON BEHALF OF THE BOARD

/s/ "Alastair McIntyre"

President, CEO and Director

For further information, please contact:

Alastair McIntyre, CEO

alastairm@apnmetals.com

Tel: (416) 434 3799

Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this release.

Forward-Looking Information: This news release contains forward-looking information within the meaning of applicable Canadian securities laws, including statements regarding proceedings in respect of certain of the Company's subsidiaries in Chile and, the timing and potential outcome of these court proceedings and related matters. Forward-looking information is based on assumptions and is subject to known and unknown risks and uncertainties that could cause actual results to differ materially from those expressed or implied. Readers are cautioned not to place undue reliance on forward-looking information. The Company undertakes no obligation to update or revise such information except as required by applicable securities laws.