Mr. Giancarlo Lagomarsino reports

MARIMACA ANNOUNCES THE APPOINTMENT OF LOUIS IRVINE TO ITS BOARD OF DIRECTORS

Marimaca Copper Corp. has appointed Louis Irvine as an independent non-executive director, effective Nov. 1, 2026. Mr. Irvine is a chartered accountant with over 30 years of experience in the mining industry, having most recently served as the chief financial officer of Ma'aden (Saudi Arabian Mining Company) from 2022 until his retirement in mid-2025, where he held a pivotal role in shaping their financial strategy and capital allocation framework. Prior to this, he held numerous executive finance roles at international mining companies, including Endeavour Mining (CFO), Anglo American (executive head of strategy and business development) and Xstrata (CFO Copper). Mr. Irvine has extensive experience in developing and financing copper projects in South America, including the Las Bambas, Quellaveco and Antapaccay operations in Peru.

Giancarlo Bruno Lagomarsino, independent chair of Marimaca Copper, commented:

"We are excited to welcome Louis to the Marimaca board. His extensive experience as a senior finance executive and listed company CFO across the mining industry, and deep experience in Latin America, will be a valuable addition to Marimaca as we develop the Marimaca oxide deposit.

"Louis brings first-hand experience financing mining projects through the development and construction phases, into operations across various commodities and jurisdictions. He joins at a pivotal time for Marimaca, as we prepare the project financing package for the MOD and advance towards a full construction decision."

About Marimaca Copper Corp.

Marimaca is a Toronto Stock Exchange-(MARI)- and Australian Securities Exchange-(MC2)-listed copper company focused on the development of high-quality copper assets in northern Chile. The company's flagship asset is the Marimaca oxide deposit project (MOD), located in Chile's prolific Antofagasta region. It is one of the few globally significant greenfield copper discoveries made in the last decade and represents a low-risk development opportunity, given the proximity to the city of Antofagasta and port of Mejillones, with substantial exploration upside. The company also controls additional exploration properties at Pampa Medina and Madrugador within the Sierra de Medina region, located 30 kilometres from the MOD, where recent drilling has identified both oxide extensions and high-grade sulphide mineralization at depth.

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