Announcement PDF RNS Number : 5298Z Great Southern Copper PLC 19 October 2026 THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION AS STIPULATED UNDER THE UK VERSION OF THE MARKET ABUSE REGULATION NO 596/2014 WHICH IS PART OF ENGLISH LAW BY VIRTUE OF THE EUROPEAN (WITHDRAWAL) ACT 2018, AS AMENDED. ON PUBLICATION OF THIS ANNOUNCEMENT VIA A REGULATORY INFORMATION SERVICE, THIS INFORMATION IS CONSIDERED TO BE IN THE PUBLIC DOMAIN. 19 October 2026 Great Southern Copper plc (“GSC” or the “Company”) Issue of Shares and Director/PDMR Shareholdings Great Southern Copper plc (LSE: GSCU), the company focused on copper-gold-silver exploration in Chile, announces that it has issued new ordinary shares of 1p each ("New Ordinary Shares") to Charles Bond, Chairman of Great Southern Copper, in accordance with the terms of Mr. Bond's letter of appointment whereby it was agreed his salary will be paid quarterly in ordinary shares. The New Ordinary Shares represent the share compensation due from 1 April 2026 to 30 September 2026 to Mr Bond. A total of 599,595 New Ordinary Shares will be issued. The details of the issuance are set out below: Period/Shareholder Value of share issuance GBP£ Number of new ordinary shares issued Number of new ordinary shares held following the issuance Percentage of the enlarged ordinary share capital Charles Bond 1/04/2026 – 30/06/2026 1/07/2026 – 30/09/2026 £7,776 £7,210 279,697 319,898 9,776,453 1.1% Admission and Total Voting Rights Application will be made for the 599,595 New Ordinary Shares, which will rank pari passu in all respects with the existing ordinary shares in the Company, to be admitted to the Standard List segment of Official List and to trading on the main market of the London Stock Exchange plc, which is expected to occur on or around 8.00 a.m. on 23 October 2026 ("Admission"). The total number of issued shares and the total number of voting rights in the Company is 907,303,084. The above figure should be used by shareholders in the Company as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change to their interest in, the share capital of the Company under the Financial Conduct Authority's Disclosure Guidance and Transparency Rules. Engage with the GSC management team directly by asking questions, watching video summaries and seeing what other shareholders have to say. Navigate to our Interactive Investor hub here: https://gscplc.com/ Enquiries: Great Southern Copper plc https://gscplc.com/link/exdAEe Sam Garrett, Chief Executive Officer +44 (0)20 4582 3500 SI Capital Limited Nick Emerson +44 (0)14 8341 3500 BlytheRay Megan Ray / James Mulligan +44 (0) 20 7138 3204 gsc@blytheray.com Notification and public disclosure of transactions by persons discharging managerial responsibilities/ person closely associated with them. 1 Details of the person discharging managerial responsibilities/person closely associated a) Name Charles Bond 2 Reason for the notification a) Position/status Chairman b) Initial notification/ Amendment Initial Notification 3 Details of the issuer, emission allowance market participant, auction platform, auctioneer or auction monitor a) Name Great Southern Copper plc b) LEI 213800RF6N9WA8PZH313 4 Details of the transaction(s): section to be repeated for (i) each type of instrument; (ii) each type of transaction; (iii) each date; and (iv) each place where transactions have been conducted a) Description of the financial instrument, type of instrument Identification code Ordinary shares of 1 pence each GB00BLB5BF24 b) Nature of the transaction Shares issued in lieu of salary c) Price(s) and volume(s) Price(s) Volume(s) 2.78p* 2.254p** 279,697 319,898 *weighted average share price from 1 April 2026 to 30 June 2026 ** weighted average share price from 1 July 2026 to 30 September 2026 e) Date of the transaction 19 October 2026 f) Place of the transaction Outside of trading venue – issued of new ordinary shares About Great Southern Copper This information is provided by RNS, the news service of the London Stock Exchange. RNS is approved by the Financial Conduct Authority to act as a Primary Information Provider in the United Kingdom. Terms and conditions relating to the use and distribution of this information may apply. For further information, please contact rns@lseg.com or visit www.rns.com. RNS may use your IP address to confirm compliance with the terms and conditions, to analyse how you engage with the information contained in this communication, and to share such analysis on an anonymised basis with others as part of our commercial services. For further information about how RNS and the London Stock Exchange use the personal data you provide us, please see our Privacy Policy. END IOEFZMMGGLRGVZM Great Southern Copper PLC is a UK-listed mineral exploration company focused on the discovery of copper-gold-silver deposits in Chile. The Company has the option to acquire mining rights to 100% of Especularita project in the under-explored coastal belt of Chile that is prospective for large scale copper-gold-silver deposits. Chile is a globally significant mining jurisdiction being the world’s largest producer and exporter of copper. The Especularita Project is located in the coastal metallogenic belt of Chile which hosts significant copper mines and deposits, including Teck’s Carmen de Andacollo copper mine, and boasts excellent access to infrastructure such as roads, power and ports. Significant historical small-scale and artisanal workings for both copper and gold are readily evident in the exploration project area. The coastal belt offers deposit type optionality for copper including porphyry and IOCG style deposits as well as newly recognised intrusive-related copper and gold deposits. Great Southern Copper is strategically positioned to support the global market for copper – a critical battery metal in the clean energy transition around the world. The Company is actively engaged in exploration and evaluation work programmes targeting both large tonnage, low to medium grade Cu- Au as well as high-grade Cu-Ag-Au deposits. Further information on the Company is available on the Company’s website: https://gscplc.com