Sumitomo Metal Mining : Document of Matters Subject to Measures for Electronic Provision

The following is an English translation of the Notice of Convocation of the 98th Ordinary General Meeting of Shareholders of Sumitomo Metal Mining Co., Ltd. (hereinafter referred to as the "Company"). The Company provides this translation for your reference and convenience only and without any warranty as to its accuracy or otherwise. The Japanese original is the sole official version and shall prevail in the event of any discrepancy between the Japanese original and this English translation.

[Delivered paper-based documents]

Document of Matters Subject to Measures for

Electronic Provision Regarding the 98th Ordinary General Meeting of Shareholders

Sumitomo Metal Mining Co., Ltd.

Securities Code No. 5713

The following matters that are not presented in this document are not presented in the paper- based documents delivered to shareholders who have requested the delivery of such documents as they are posted on the Company's website and Tokyo Stock Exchange's website, which are presented on page 1 of this notice, in accordance with the laws and regulations and Article 16, Paragraph 2 of the Articles of Incorporation of the Company.

• Main businesses, etc., Main offices and plants, etc., Employees, Summary of details of Contract for Limitation of Liability, Matters related to Directors and Officers liability insurance contract, Matters related to Accounting Auditor, Matters related to the development of systems necessary to ensure the properness of operations and Basic policies related to the way a person is to control the decisions on the financial and business policies of the Company
• Consolidated Statement of Changes in Equity and Notes on the Consolidated Financial Statements
• Non-consolidatedStatement of Changes in Equity and Notes on the Non-consolidated Financial Statements

The content presented in this document is part of the documents audited by the Accounting Auditor when preparing the accounting audit report and by the Audit & Supervisory Board Members when preparing the audit report.

Business Report

(From April 1, 2022 to March 31, 2023)

1. Matters relating to the current status of the corporate group

1. Business activities and results

In the Group's performance in the fiscal year ended March 31, 2023, consolidated net sales increased year on year mainly due to the substantial depreciation of the yen, increased prices of nickel, and good sales of battery materials for automobile batteries. Consolidated profit before taxes decreased year on year because gain on sales associated with the transfer of all the interests in Sierra Gorda Copper Mine (Chile) and share of profit of investments accounted for using equity method regarding the mine were recorded for the previous fiscal year, but there is no such factor for the fiscal year under review. Profit attributable to owners of parent decreased year on year mainly due to a decrease in consolidated profit before tax.

The economic environment and other factors during fiscal 2022 were as follows.

Overview of the world economy

The growth slowed mainly due to Russia's prolonged invasion of Ukraine, global inflation and monetary contraction, and China's strict COVID-19 prevention policy followed by a temporary rapid spread after the end of the policy.

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Mineral Resources Segment

Main businesses

Exploration, development, production, and sales of non-ferrous metal resources in Japan and overseas

The Hishikari Mine (Kagoshima Prefecture) continued steady operation as planned.

Production volume at the Morenci Copper Mine (the United States) increased year on year because of the end of a COVID-19 prevention measure that reduced the operating capacity of mineral ore mills. Production volume at the Cerro Verde Copper Mine (Peru) rose year on year due mainly to an increase in ore grade and a rise in mill plant operation rates.

Segment income decreased year on year, despite the significant depreciation of the yen. This is mainly due to decreased copper prices, the decline in the volume of gold shipped from the Hishikari Mine in conjunction with its transition to sustainable production, and the lack of recording of gain on sales associated with the transfer of all the interests in Sierra Gorda Copper Mine and share of profit of investments accounted for using equity method related to the mine in the fiscal year under review (as they were recorded for the previous fiscal year).

(Note) Sociedad Minera Cerro Verde S.A.A. is a company accounted for by the equity method and is not included in net sales, but is included in segment income.

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Smelting & Refining Segment

Main businesses

Smelting and refining and sales of copper, nickel, ferronickel, gold, silver, etc.

The production volume and sales volume of electrolytic copper increased from the previous fiscal year.

The production volume and sales volume of electrolytic nickel were affected by a shortage of raw materials, but kept the same level as the previous fiscal year, supported by an increased production volume toward the end of the fiscal year.

The production volume and sales volume of ferronickel decreased year on year.

At Coral Bay Nickel Corporation (Philippines), where intermediate raw materials for nickel are manufactured, the production volume remained at the same level as in the previous fiscal year. At Taganito HPAL Nickel Corporation (Philippines), where intermediate raw materials for nickel are also manufactured, the production volume increased from the previous fiscal year, in which equipment failures caused decreased production.

Segment income increased year on year, due mainly to the significant depreciation of the yen and the rising price of nickel, despite the decline in copper prices.

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Materials Segment

Main businesses

Manufacturing and sales of battery materials and advanced materials such as powder materials and crystal materials

Regarding battery materials for automobile batteries, demand remained steady, and sales had strong performance against the backdrop of the shift toward decarbonization.

Regarding powder materials and crystal materials, sales volume decreased year on year due to weakened demand for smartphones and others in China and other regions worldwide.

Segment income decreased year on year, which mainly resulted from the stagnant smartphone markets.

• Net sales and profit of each segment include intersegment transactions.
• Figures for consolidated net sales are the sum of external net sales after eliminating intersegment transactions.

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