Core Viewpoint - MAC Copper Limited has announced the lodging of the Royal Court of Jersey's order sanctioning the acquisition of 100% of its issued share capital by Harmony Gold (Australia) Pty Ltd, a subsidiary of Harmony Gold Mining Company Limited [1] Group 1 - MAC Copper Limited is listed on both NYSE (MTAL) and ASX (MAC) [1] - The acquisition will result in Harmony Gold owning the entire issued share capital of MAC Copper Limited [1]

ST. HELIER, Jersey--(BUSINESS WIRE)--MAC Copper Limited ARBN 671 963 198 (NYSE:MTAL; ASX:MAC) MAC Copper Limited (NYSE:MTAL, ASX:MAC) ("MAC†or the "Company†) is pleased to announce that the Royal Court of Jersey (the "Court†) has today made orders sanctioning the proposed acquisition of 100% of the issued share capital in MAC by Harmony Gold (Australia) Pty Ltd (a wholly owned subsidiary of Harmony Gold Mining Company Limited (JSE:HAR, NYSE:HMY)) ("Harmony†) by way of a Jersey law scheme of ar. ...

ST. HELIER, Jersey--(BUSINESS WIRE)--MAC Copper Limited ARBN 671 963 198 (NYSE:MTAL; ASX:MAC) MAC Copper Limited (NYSE:MTAL, ASX:MAC) ("MAC†or the "Company†) is pleased to provide the following update on the proposed acquisition of 100% of the issued share capital in MAC by Harmony Gold (Australia) Pty Ltd (a wholly owned subsidiary of Harmony Gold Mining Company Limited (JSE:HAR, NYSE:HMY)) ("Harmony†) by way of a Jersey law scheme of arrangement pursuant to Article 125 of the Companies (Jers. ...

Financial Data and Key Metrics Changes - The proxy position at the general meeting was reported to be more than 97% in favor of the poll, with 83.11% of the register having voted [11][17]. Business Line Data and Key Metrics Changes - No specific data on individual business lines was provided in the meeting records. Market Data and Key Metrics Changes - The company has a significant presence in multiple markets, being listed on both the Australian Stock Exchange and the New York Stock Exchange, indicating a global shareholder base [17]. Company Strategy and Development Direction - The company is focused on implementing a scheme that requires authorization from the directors, which includes dealing with ancillary matters and altering the company's articles of association [20][21]. Management's Comments on Operating Environment and Future Outlook - The CEO noted a high turnout of total shareholders voting and an overwhelmingly favorable vote for the transaction, indicating confidence in the company's direction despite some press coverage suggesting discontent among shareholders [13][14]. Other Important Information - The meeting was designed to accommodate shareholders from different time zones, ensuring participation from North America, Australia, and Europe [17][19]. Q&A Session Summary Question: How many shareholders attended the meeting? - Seven shareholders were present in person, with online attendance numbers not immediately available [9]. Question: Has there been any protest votes regarding the takeover price? - The CEO confirmed that there has not been a protest vote, as the votes indicated overwhelming support for the transaction [13][14]. Question: Will the company publish a full copy of the webcast for shareholders? - The management did not consider this question relevant, citing overwhelming support for the meeting's approval [15]. Question: Why was the meeting scheduled late on a Friday night? - The company engaged a proxy solicitation firm to encourage shareholder participation and noted that the timing was chosen to accommodate global shareholders [16][17].

Financial Data and Key Metrics Changes - The proxy position at the general meeting was reported to be more than 97% in favor of the poll, with 83.11% of the register having voted [11][15]. Business Line Data and Key Metrics Changes - No specific data on individual business lines was provided during the meeting [6]. Market Data and Key Metrics Changes - The company has a significant presence of shareholders in Europe, North America, and Australia, indicating a global market engagement [16]. Company Strategy and Development Direction and Industry Competition - The company is focused on implementing a scheme that requires approval from shareholders and the court, indicating a strategic move towards consolidation or acquisition [19]. - The management emphasized strong engagement with shareholders and efforts to encourage participation in the voting process, reflecting a commitment to shareholder interests [15][16]. Management's Comments on Operating Environment and Future Outlook - The CEO noted that despite some press coverage regarding the transaction, shareholders overwhelmingly voted in favor of the scheme, indicating confidence in the company's direction [13]. - Management expressed comfort with the high turnout of shareholders voting, suggesting a positive outlook on shareholder engagement and support for the company's initiatives [15][16]. Other Important Information - The meeting was conducted with a focus on ensuring that all shareholders, regardless of their location, had the opportunity to participate, reflecting the company's global operational strategy [16]. Q&A Session Summary Question: Attendance of shareholders at the meeting - There were seven shareholders in attendance at the meeting in Jersey [9]. Question: Concerns about the takeover price - The proxy position was reported to be more than 97% in favor, indicating no significant protest votes against the takeover [11][13]. Question: Availability of meeting materials for shareholders - The management did not consider the request for publishing a full copy of the webcast relevant, citing overwhelming support for the previous meeting [14]. Question: Scheduling of meetings for Australian shareholders - The company engaged a proxy solicitation firm to encourage participation, and noted that the meeting time was chosen to accommodate shareholders across multiple time zones [15][16].

Financial Data and Key Metrics Changes - The proxy position at the general meeting is more than 97% in favor of the poll, with 83.11% of the register having voted [11][15]. Business Line Data and Key Metrics Changes - No specific business line data or key metrics were discussed in the meeting [6]. Market Data and Key Metrics Changes - No specific market data or key metrics were discussed in the meeting [6]. Company Strategy and Development Direction and Industry Competition - The company is focused on ensuring strong shareholder engagement and participation in meetings, with efforts made to accommodate shareholders across different time zones [16]. - The company has been set up and run as a global business, listed on both the Australian Stock Exchange and the New York Stock Exchange, indicating a broad market presence [16]. Management's Comments on Operating Environment and Future Outlook - Management noted a high turnout of total shareholders voting and an overwhelmingly favorable vote for the transaction, despite some press coverage suggesting discontent among shareholders [13]. - The CEO emphasized that there has been strong engagement with shareholders, and the company is comfortable with the level of participation and support for the scheme [16]. Other Important Information - The meeting included a discussion on the voting process and the importance of shareholder participation, with a proxy solicitation firm engaged to encourage voting [15]. - The company plans to comply with all regulations regarding the disclosure of voting outcomes [17]. Q&A Session Summary Question: How many shareholders attended the meeting? - There were seven shareholders in attendance at the meeting in Jersey [9]. Question: Has there been any protest votes regarding the takeover price? - The proxy position is more than 97% in favor, indicating no significant protest votes [11][13]. Question: Will the company publish a full copy of the webcast for shareholders? - The company does not consider this issue material and will not publish the webcast [14]. Question: Why was the meeting scheduled late on a Friday night? - The timing was designed to accommodate shareholders in North America, Australia, and Europe, ensuring participation from all regions [16]. Question: Will headcount numbers be included in the voting outcome disclosure? - The company assured compliance with ASX and NYSE regulations regarding the publication of voting results [17].

Exhibit 99.1 Table of Contents 25 August 2025 APPENDIX 4D HALF YEAR ENDED 30 JUNE 2025 ST. HELIER, Jersey - (BUSINESS WIRE) – MAC Copper Limited (NYSE: MTAL; ASX:MAC) The Directors of MAC Copper Limited ARBN 671 963 198 (NYSE: MTAL; ASX: MAC), a private limited company incorporated under the laws of Jersey, Channel Islands ("MAC" or the "Company") are pleased to provide the Appendix 4D and the Half Year Report, for the half year ended 30 June 2025. The Appendix 4D and the Half Year Report, comprising this p ...

Financial Data and Key Metrics Changes - The company reported a liquidity position of approximately USD 196 million at the end of June, with actual cash on the balance sheet amounting to USD 102 million [4][28] - The company achieved record quarterly operating free cash flow of about USD 42 million, driven by a 23% increase in production and an 8% increase in copper grade [9][26] - Interest costs were significantly reduced, with an average weighted interest cost decrease of more than 30% due to refinancing, leading to expected annual savings of USD 14 million [27][28] Business Line Data and Key Metrics Changes - The company produced just under 10,600 tons of copper in Q2, representing a 23% increase quarter on quarter, with a copper grade of 4.4%, an 8% increase from the previous quarter [5][7] - Growth capital expenditure increased by 139% for the quarter, primarily driven by the ventilation project and the Mariner mine [24][25] - Sustaining capital expenditure is focused on the Stage 10 TSF, which is on track for completion in Q4 of this year [26] Market Data and Key Metrics Changes - The company maintained its production guidance of 43,000 to 48,000 tons for the year, with expectations to be in the lower half of that range [9][10] - The average realized copper price increased by 3% over the quarter, contributing positively to cash flow [26] Company Strategy and Development Direction - The company is focused on consistent, safe, and low-cost high-grade production while advancing the Harmony transaction and progressing key growth projects [13][32] - The ventilation project and the Mariner mine are key growth initiatives, with significant capital expenditures planned to support these projects [24][33] - Exploration efforts are ongoing, with a new drilling initiative targeting a strong anomaly identified north of the mine [38] Management's Comments on Operating Environment and Future Outlook - Management expressed confidence in the company's strong balance sheet and operational performance, noting a significant improvement in safety records [4][41] - The company is optimistic about production levels in July, expecting to produce between 5,900 to 6,200 tons of copper at an average grade of around 7% [17][22] - Management acknowledged the challenges posed by the transaction announcement but noted that operations have stabilized and production has ramped up [6][41] Other Important Information - The company has executed restructuring agreements with Cisco and Glencore related to the Harmony transaction, with a court hearing scheduled for July 30 [11][15] - The company donated AUD 100,000 to the local Cobar Shire Council's museum effort, emphasizing its commitment to the local community [14] Q&A Session Summary Question: No questions were raised during the session - There were no questions from participants during the call, and the session concluded with closing remarks from management [42][44]

Financial Performance & Liquidity - Q2 2025 saw record quarterly operational free cash flow (FCF) of approximately US$42 million[18] - Cash and cash equivalents were approximately US$102 million at the end of Q2 2025[14, 18, 54] - Liquidity of approximately US$196 million was available, including an undrawn revolving facility of approximately US$59 million[13, 54] - C1 costs achieved for Q2 2025 was US$1.48/lb, with June 2025 achieving US$0.94/lb[18] - Total cash cost was US$2.17/lb[18] Production & Operations - Copper production increased by 23% quarter-over-quarter (QoQ) to 10,587 tonnes in Q2 2025[18, 34] - Copper grade was 4.4% for Q2 2025, an increase of 8% QoQ[18] - Record daily copper production of 385 tonnes was achieved under MAC ownership[18] - Capital expenditure increased in Q2 with higher capitalised development driven by a 46% increase in capital development meters compared to previous quarter combined with delivery of new operational drills[49] Growth Projects & Future Targets - The company is targeting copper equivalent production of over 50ktpa by 2026[13] - The ventilation project is progressing, targeting completion by Q3 2026[14, 19, 72] - First ore from the new Merrin Mine is targeted for Q4 2025[14, 19, 64] Harmony Transaction - MAC entered into Restructure Documents regarding the Harmony Transaction[19, 29] - The transaction is subject to shareholder and regulatory approvals[32]

Key Highlights - MAC achieved a 67% increase in the Life of Mine (LOM) [27, 73] - The company saw a 64% increase in reserves [28, 74] - Mineral Resources increased by 42% [30, 60, 76] - Q1 2024 copper production reached 8,786 tonnes with C1 costs of US$2.15/lb [36, 82] - Approximately US$127 million of interest-bearing liabilities were repaid in Q1 [36, 82] Financial Position - The fully-diluted market capitalization stands at US$1,250 million [21] - Liquidity as of March 31, 2024, was approximately US$100 million [21, 36, 54, 82] - The company completed an ASX IPO with proceeds of A$325 million (US$214 million) [54] Production Guidance - Copper production guidance for 2024 is set between 38Kt and 43Kt, with expectations to exceed 50kt by 2026 [36, 71, 82] - The mine life, based on Mineral Reserves, now extends to the end of 2034 [70, 81] Operational Improvements - Tonnes milled per employee increased by 19% from Q1 2023 to Q1 2024 [42] - Development costs per meter decreased significantly from US$18,677 in Q1 2023 to US$15,478 in Q1 2024 [49]