Material event report

What happened

MATERIAL EVENT REPORT / Matters subject to stock exchange reporting duty To: Financial Services Commission / Korea Exchange August 13, 2026

Company name: Koas Co., Ltd. CEO: Noh Byeong-gu Head office address: 17 Seonyu-ro 52-gil, Yeongdeungpo-gu, Seoul (Dangsan-dong 6-ga) (Phone) 02-2163-6000 (Website) http://www.ikoas.com Preparer: (Title) Executive Director (Name) Jang Hyeong-gi (Phone) 02-2163-6000

Decision to acquire own bonds with stock warrants before maturity

1. Type of bond Series: 4 Type: Unregistered, coupon-bearing, unsecured, non-separable, privately placed bonds with stock warrants

2. Bond issue date: 2024-09-11 3. Bond issuance method: Private placement 4. Bond maturity date: 2027-09-11 5. Total face value (electronically registered) of the bonds (KRW): 398,300,168 6. Face value (electronically registered) amount of bonds subject to acquisition (KRW): 8,296,447 7. Acquisition decision date: 2026-08-13 8. Acquisition amount Amount (KRW): 8,296,447 Basis for calculation: principal and interest payment (scheduled) date: 2026-09-11 Source of acquisition funds: Own funds 9. Acquisition method: Over-the-counter purchase 10. Reason for acquisition before maturity: Exercise of bondholder's early redemption request (put option) 11. Future handling plan: Scheduled for retirement after acquisition 12. Matters related to the stock warrants Exercise ratio (%): 100 Exercise price as of report date (KRW/share): 2,994 Whether the bond and the warrant are separable: Non-separable Type of shares to be issued upon exercise: Common shares Number of shares: 2,721 As % of total shares: 0.02 Rights exercise period - Start date: 2025-09-11; End date: 2027-08-11 13. Remaining face value (electronically registered) of bonds after acquisition (KRW): 390,003,721 14. Whether subject to Fair Trade Commission filing: Not applicable 15. Other matters for reference in investment decisions - The above "7. Acquisition decision date" is the date internal approval for this bond acquisition was completed. - Details related to the 4th series bonds with stock warrants are as follows: 1) Total issued amount: KRW 10,000,000,000 2-1) Total amount already converted: KRW 8,157,905,789 2-2) Total amount already acquired (retired): KRW 1,443,794,043 3) Balance before this acquisition: KRW 398,300,168 4) Total amount to be acquired this time: KRW 8,269,447 (as stated in the filing; inconsistent with the KRW 8,296,447 given in items 6 and 8 above) 5) Balance after acquisition: KRW 390,003,721 - The "shares to be issued upon conversion" referenced under "12. Matters related to conversion" above (as stated in the filing, though this report concerns stock warrants rather than conversion) is the number of shares and the ratio to total shares that would be issued if the bonds acquired this time were converted; the portion acquired this time will not be converted but will instead be retired.

[Matters related to the seller] Seller name: - Relationship with the company or largest shareholder: - Basis for selection: Bondholder Transaction history and plans within 6 months before/after the acquisition decision: - Face value of bonds sold (KRW): 8,296,447 Remarks: -