[Amended] Change of largest shareholder

What happened

Korea Advanced Materials / Change of Largest Shareholder / (2026.08.31) Change of Largest Shareholder Amendment Report Amendment date: 2026-08-31

1. Disclosure document being amended: Change of Largest Shareholder 2. Filing date of the disclosure document being amended: August 26, 2026 3. Reason for amendment: Correction of an error and addition of content

4. Amended items Amendment item: "1. Details of the change" Before amendment: Largest shareholder, etc. after the change: Nakamoto Investment Partnership After amendment: Largest shareholder, etc. after the change: Nakamoto Investment Partnership and 1 other

Amendment item: "6. Other matters for reference in investment decisions" Before amendment: - Nakamoto Investment Partnership: Shares transferred and equity ratio 2,214,710 shares (7.76%); Transfer amount KRW 6,710,571,300 - Flake Co., Ltd.: Shares transferred and equity ratio 1,251,346 shares (4.38%); Transfer amount KRW 3,791,578,380

After amendment: - Nakamoto Investment Partnership: Shares transferred and equity ratio 2,214,710 shares (7.76%); Transfer amount KRW 6,710,571,300; Date of execution of the transfer agreement and final payment date: August 26, 2026 - Flake Co., Ltd.: Shares transferred and equity ratio 1,251,346 shares (4.38%); Transfer amount KRW 3,791,578,380; Date of execution of the transfer agreement and final payment date: August 26, 2026 - The Series 10 convertible bonds held by Nakamoto Investment Partnership have a face value of KRW 6,800 million, approximately 90.67% of the total face value of the Series 10 convertible bonds of KRW 7,500 million. Applying that ratio to the external valuation institution's total valuation of the Series 10 convertible bonds of KRW 7,399,852,554 gives a valuation amount of KRW 6,709,199,649. - The Series 12 convertible bonds held by Flake Co., Ltd. have a face value of KRW 4,000 million, approximately 34.19% of the total face value of the Series 12 convertible bonds of KRW 11,700 million. Applying that ratio to the external valuation institution's total valuation of the Series 12 convertible bonds of KRW 11,841,531,399 gives a valuation amount of KRW 4,048,386,803. - The above valuation amounts were calculated based on the results of the external valuation institution's assessment as of the valuation reference date of August 24, 2026.

Amendment item (within "Matters Concerning the Largest Shareholder After the Change (Where a Partnership)," item 4, transactions over the most recent 3 years): After amendment: Prior year: Acquisition of convertible bonds, KRW 4.0 billion; Acquisition of shares and equity securities of other companies, KRW 4.0 billion (as stated in the filing)

Change of Largest Shareholder

1. Details of the change Largest shareholder, etc. before the change: Satoshi Holdings Co., Ltd.; Shares held: 3,466,056; Ownership ratio: 12.14% Largest shareholder, etc. after the change: Nakamoto Investment Partnership and 1 other; Shares held: 3,466,056; Ownership ratio: 12.14%

2. Reason for the change: Change resulting from performance of a share transfer agreement - Whether the change resulted from the acquisition of forfeited shares: No - Whether the transferred shares are subject to a mandatory holding period: No

3. Purpose of the equity acquisition: Participation in management - Method of financing the acquisition: Own funds (KRW) 10,502,149,680; Borrowed funds (KRW) -; Lender -; Borrowing period - to -; Collateral details - - Plan to appoint or dismiss executives after the acquisition: Not applicable

4. Date of change: 2026-08-26 5. Date the change was confirmed: 2026-08-26

6. Other matters for reference in investment decisions - The ownership ratios in "1. Details of the change" above were calculated based on the Company's total issued shares of 28,544,307. - Method of financing the acquisition: Satoshi Holdings Co., Ltd., the largest shareholder before the change, entered into a share transfer agreement to transfer its 3,466,056 shares to Nakamoto Investment Partnership and Flake Co., Ltd., as follows. - Nakamoto Investment Partnership: Shares transferred and equity ratio 2,214,710 shares (7.76%); Transfer amount KRW 6,710,571,300; Date of execution of the transfer agreement and final payment date: August 26, 2026 - Flake Co., Ltd.: Shares transferred and equity ratio 1,251,346 shares (4.38%); Transfer amount KRW 3,791,578,380; Date of execution of the transfer agreement and final payment date: August 26, 2026 - The method of financing the acquisition was recorded as own capital, paid in by way of set-off using the Series 10 and Series 12 convertible bonds of Satoshi Holdings Co., Ltd. held by the largest shareholder, etc. after the change. - The Series 10 convertible bonds held by Nakamoto Investment Partnership have a face value of KRW 6,800 million, approximately 90.67% of the total face value of the Series 10 convertible bonds of KRW 7,500 million. Applying that ratio to the external valuation institution's total valuation of the Series 10 convertible bonds of KRW 7,399,852,554 gives a valuation amount of KRW 6,709,199,649. - The Series 12 convertible bonds held by Flake Co., Ltd. have a face value of KRW 4,000 million, approximately 34.19% of the total face value of the Series 12 convertible bonds of KRW 11,700 million. Applying that ratio to the external valuation institution's total valuation of the Series 12 convertible bonds of KRW 11,841,531,399 gives a valuation amount of KRW 4,048,386,803. - The above valuation amounts were calculated based on the results of the external valuation institution's assessment as of the valuation reference date of August 24, 2026. * Related disclosures: Not applicable.

[Details of the Change] Satoshi Holdings Co., Ltd.: Largest shareholder before the change; Before: 3,466,056 shares, 12.14%; After: -, - Nakamoto Investment Partnership: Largest shareholder after the change; Before: -, -; After: 2,214,710 shares, 7.75% Flake Co., Ltd.: Related party of the largest shareholder after the change; Before: -, -; After: 1,251,346 shares, 4.38%

[Matters Concerning the Largest Shareholder After the Change (Where a Partnership)]

1. Basic information on the partnership - Legal basis for formation: The Civil Act - Name: Nakamoto Investment Partnership - Registration number: 730-80-03449 - Number of investors (persons): 2 - Total partnership assets (KRW): 6,800,000,000 - Representative partner: Lee Hee-seup; Equity (%) - - Managing partner: -; Equity (%) - - Largest investor: Kim Byeong-jin; Equity (%) 100 - Major investors (10% or more): Largest investor Kim Byeong-jin, 100% - Executive career of the representative partner, managing partner, and largest investor: Kim Byeong-jin / Flake Co., Ltd. / Unlisted / - / CEO / Date joined 2016-12-01 / Date left - / - - History as largest shareholder of a listed company: - / - / - / - / Start date - / End date - / -

2. Key financial matters, etc. (Unit: KRW million): Fiscal year - / Settlement month - / Total assets - / Capital stock - / Total liabilities - / Revenue - / Total equity - / Net income - / External auditor - / Audit opinion -

3. Relationship with the listed company - Relationship between the listed company and the largest shareholder (partnership): Major shareholder - Relationship between the listed company's executives and the largest shareholder (partnership): Kim Byeong-jin; Relationship: Director; Relationship with largest shareholder (partnership): Largest investor

4. Transactions between the listed company and the largest shareholder (partnership) over the most recent 3 years (excluding ordinary transactions) Current year: - Prior year: Acquisition of shares and equity securities of other companies, KRW 4.0 billion Year before that: -