[Amended] Change of largest shareholder

What happened

Daedong Steel Co., Ltd. / Change of Largest Shareholder / (2026.09.18) Correction Report on Change of Largest Shareholder

Correction Date: 2026-09-18

1. Disclosure Document Subject to Correction Change of Largest Shareholder

2. Submission Date of Disclosure Document Subject to Correction 2026-06-01

3. Reason for Correction Change of largest shareholder due to inheritance

4. Correction Details

Correction Item | Before Correction | After Correction

1. Change of Content Largest Shareholder, etc.: Lim Hyung-gi and 3 others | Number of Shares Owned (shares): 3,999,149 | Ownership Ratio (%): 41.44 Largest Shareholder, etc.: Lim Ju-hee and 1 other | Number of Shares Owned (shares): 4,110,473 | Ownership Ratio (%): 42.59

2. Reason for Change Change due to death of largest shareholder Lim Hyung-gi | Inheritance completed due to death of largest shareholder and Representative Director Lim Hyung-gi

3. Date of Change 2026-05-31 | 2026-09-18

4. Date of Change Confirmation 2026-06-01 | 2026-09-18

5. Other Matters for Reference in Investment Decisions The largest shareholder is expected to change due to the death of the existing largest shareholder and Representative Director Lim Hyung-gi. Following completion of the inheritance procedures regarding the inherited shares of Representative Director Lim Hyung-gi, a re-disclosure is planned. The inheritance procedures due to the death of the existing largest shareholder and Representative Director Lim Hyung-gi have been completed, and the largest shareholder has changed to Representative Director Lim Ju-hee. The date of change in item 4 above is the completion date of the inherited property division agreement. The date of change confirmation in item 5 above is the date confirmed by the company through the "Report on Large-Scale Shareholding of Stocks, etc."

- Change of Largest Shareholder

1. Change of Content Before Change | Largest Shareholder, etc.: Lim Hyung-gi and 3 others | Number of Shares Owned (shares): 3,999,149 | Ownership Ratio (%): 41.44 After Change | Largest Shareholder, etc.: Lim Ju-hee and 1 other | Number of Shares Owned (shares): 4,110,473 | Ownership Ratio (%): 42.59

2. Reason for Change Inheritance completed due to death of largest shareholder and Representative Director Lim Hyung-gi - Whether change due to acquisition of treasury shares: No - Whether mandatory holding period applies to acquired shares: No

3. Purpose of Equity Acquisition - Method of Raising Acquisition Funds: Own funds (KRW) - Borrowed funds (KRW) - Lender - Borrowing Period - ~ - Collateral Details - - Plan for Appointment/Dismissal of Officers After Acquisition: -

4. Date of Change 2026-09-18

5. Date of Change Confirmation 2026-09-18

6. Other Matters for Reference in Investment Decisions The inheritance procedures due to the death of the existing largest shareholder and Representative Director Lim Hyung-gi have been completed, and the largest shareholder has changed to Representative Director Lim Ju-hee. The date of change in item 4 above is the completion date of the inherited property division agreement. The date of change confirmation in item 5 above is the date confirmed by the company through the "Report on Large-Scale Shareholding of Stocks, etc."

※ Related Disclosure

- [Detailed Change Details]

Name (Corporate Name, Partnership Name, Other Organization Name) | Relationship | Before Change | After Change | Remarks Number of Shares (shares) | Ownership Ratio (%) | Number of Shares (shares) | Ownership Ratio (%)

Lim Hyung-gi | Largest Shareholder Before Change | 2,009,247 | 20.82 | - | - | Deceased

O Su-bok | Special Related Party of Largest Shareholder Before Change | 1,000,000 | 10.36 | - | - | Special Related Party of Largest Shareholder Before Change (Spouse) / Special Related Party of Largest Shareholder After Change (Mother) / Change in number of shares due to gift on 2026-08-28 (Recipients: Lim Ju-hee, Lim Ji-hyun)

Lim Ju-hee | Special Related Party of Largest Shareholder Before Change | 542,187 | 5.61 | 2,104,724 | 21.81 | Inheritance (Deceased: Lim Hyung-gi) +1,004,624 / Gift (Donor: O Su-bok) +500,000

Lim Ji-hyun | Special Related Party of Largest Shareholder Before Change | 447,715 | 4.63 | 2,005,749 | 20.78 | Largest Shareholder After Change / Special Related Party (Registered Officer) / Inheritance (Deceased: Lim Hyung-gi) +1,004,623 / Gift (Donor: O Su-bok) +500,000

[Information Regarding the Largest Shareholder After Change (Individual)]

1. Basic Information of Individual Name: Lim Ju-hee | Nationality: Republic of Korea

- Officer Career of Individual Name | Company Name | Listed Status | Delisting Date (for delisted corporations) | Position | Date of Joining | Date of Resignation | Remarks Lim Ju-hee | Daedong Steel Co., Ltd. | Listed (KOSDAQ) | - | Representative Director | 2008-01-14 | - | -

- History of Largest Shareholder in Listed Corporations of Individual Name | Company Name | Listed Status | Delisting Date (for delisted corporations) | Period as Largest Shareholder (Start Date) | Period as Largest Shareholder (End Date) | Remarks Lim Ju-hee | Daedong Steel Co., Ltd. | Listed (KOSDAQ) | - | 2026-09-18 | - | -

2. Relationship Between the Listed Corporation and the Largest Shareholder (Individual) Representative Director

3. Recent 3-Year Transaction History Between the Listed Corporation and the Largest Shareholder (Individual) (Excluding Routine Transactions) Category | Transaction Details Current Year | None Previous Year | None Year Before Previous | None