Change of largest shareholder

What happened

S-Oil/Change of Largest Shareholder/(2026.10.01) Change of Largest Shareholder

Change of Largest Shareholder 1. Change Details Previous largest shareholder, etc.: Aramco Overseas Company B.V. (AOCBV) and 5 others Shares held: 71,411,335 Ownership (%): 63.43 New largest shareholder, etc.: Aramco Downstream Asia Pte. Ltd (ADA) and 5 others Shares held: 71,411,335 Ownership (%): 63.43 2. Reason for Change: Transfer of S-Oil equity between AOCBV and ADA, both affiliates of Saudi Arabian Oil Company (SAOC) 3. Purpose of Equity Acquisition: Restructuring of equity ownership among affiliated companies - Method of funding acquisition: Transfer of a bond (promissory note) - Plan to appoint/dismiss officers after acquisition: No change 4. Change Date: 2026-10-01 5. Change Confirmation Date: 2026-10-01 6. Other Matters for Investment Reference - This transaction is between two affiliates of SAOC, under which ADA, another SAOC affiliate, acquires all S-Oil shares held by AOCBV (71,387,560 common shares and 351,502 preferred shares). - There is no change in the number of shares held or ownership ratio of the largest shareholder group as a result of this transaction. The largest shareholder, AOCBV, transfers all of its common and preferred shares to ADA; the shares held by the 5 related parties (23,775 common shares, 465 preferred shares) are unchanged. - The "shares held before/after change" in "1. Change Details" above consist of 71,387,560 common shares held by the largest shareholder and a total of 23,775 common shares held by the 5 related parties. - The "method of funding acquisition" in "3. Purpose of Equity Acquisition" above refers to payment for the share transfer using a bond issued by SAOC. - "4. Change Date" and "5. Change Confirmation Date" above refer to the settlement date of this share transaction. - ADA was established on December 15, 2025 for the purpose of a broader organizational restructuring within the SAOC group. Upon completion of the restructuring, ADA will hold SAOC's global asset portfolio as an affiliate of SAOC. ※ Related Disclosures: -

[Detailed Change Information] Name (corporation) | Relationship | Before Change (Shares / Ownership %) | After Change (Shares / Ownership %) | Remarks AOCBV: Previous largest shareholder; Before: 71,387,560 shares, 63.41%; After: 0 shares, 0.00%; Remarks: - ADA: New largest shareholder; Before: 0 shares, 0.00%; After: 71,387,560 shares, 63.41%; Remarks: - Ahn Jong-beom: Related party of the new largest shareholder; Before: 9,140 shares, 0.01%; After: 9,140 shares, 0.01%; Remarks: Affiliated company officer Bang Ju-wan: Related party of the new largest shareholder; Before: 10,000 shares, 0.01%; After: 10,000 shares, 0.01%; Remarks: Affiliated company officer Kang Min-su: Related party of the new largest shareholder; Before: 3,888 shares, 0.00%; After: 3,888 shares, 0.00%; Remarks: Affiliated company officer Kang Gyeong-don: Related party of the new largest shareholder; Before: 300 shares, 0.00%; After: 300 shares, 0.00%; Remarks: Affiliated company officer Kim Seung-hu: Related party of the new largest shareholder; Before: 447 shares, 0.00%; After: 447 shares, 0.00%; Remarks: Affiliated company officer