[Amended] Material event report (decision to redeem own convertible bonds early)

A later amendment corrects this filing, so the terms on this page may be out of date. See the latest version (2026-09-11) →

What happened

OptiCore Co., Ltd. Amendment report (filing) August 31, 2026

1. Disclosure document being amended: Decision to redeem own convertible bonds before maturity 2. Original filing date of the disclosure document being amended: June 30, 2026 3. Amendment details Item: 8. Acquisition amount - Amount (KRW) Reason for amendment: Amendment due to a change in the installment repayment schedule Before amendment: 3,818,900,950 After amendment: 3,820,151,500

Item: 15. Other matters for investors' reference Before amendment (Note 2): see below After amendment (Note 1): see below

After amendment - installment repayment details Installment | Date | Principal repaid | Interest repaid | Total payment 1st | 2026-06-30 | 700,000,000 | 16,626,960 | 716,626,960 2nd | 2026-09-15 | 1,000,000,000 | 30,172,260 | 1,030,172,260 3rd | 2026-10-31 | 1,000,000,000 | 34,075,130 | 1,034,075,130 4th | 2026-12-31 | 1,000,000,000 | 39,277,150 | 1,039,277,150 Total | - | 3,700,000,000 | 120,151,500 | 3,820,151,500

Before amendment - installment repayment details Installment | Date | Principal repaid | Interest repaid | Total payment 1st | 2026-06-30 | 700,000,000 | 16,626,960 | 716,626,960 2nd | 2026-08-31 | 1,000,000,000 | 28,921,710 | 1,028,921,710 3rd | 2026-10-31 | 1,000,000,000 | 34,075,130 | 1,034,075,130 4th | 2026-12-31 | 1,000,000,000 | 39,277,150 | 1,039,277,150 Total | - | 3,700,000,000 | 118,900,950 | 3,818,900,950

Material event report / Exchange disclosure obligation matter To the Financial Services Commission / Korea Exchange June 30, 2026 Company name: OptiCore Co., Ltd. CEO: Moon Yu-seok Head office address: Room 501, 602 Dongtan-gihung-ro, Yeongcheon-dong, The First Tower 3, Hwaseong-si, Gyeonggi-do Phone: 070-4492-5446; Website: http://www.opticore.co.kr Person responsible for preparation: (Title) Head of Management Support Division, (Name) Kim Hee-jin, Phone: 070-4492-5446

Decision to redeem own convertible bonds before maturity 1. Type of bond: Series 5; registered coupon-bearing unsecured private-placement convertible bonds 2. Bond issue date: September 17, 2025 3. Bond issuance method: Private placement 4. Bond maturity date: September 17, 2028 5. Total face value (electronically registered) of the bonds (KRW): 3,700,000,000 6. Face value (electronically registered amount) of the bonds to be acquired (KRW): 3,700,000,000 7. Acquisition decision date: June 30, 2026 8. Acquisition amount: Amount (KRW) 3,820,151,500; basis of calculation - principal and interest payment (scheduled) date December 31, 2026; source of acquisition funds - own funds 9. Acquisition method: Over-the-counter purchase 10. Reason for acquisition before maturity: Mutual agreement with the bondholder 11. Future handling plan: To be decided at a future board of directors meeting (planned resale or retirement) 12. Matters concerning conversion: Conversion ratio (%) 100; conversion price as of the report date (KRW/share) 3,428; type of shares to be issued upon conversion: OptiCore Co., Ltd. registered common stock; number of shares 1,079,346; ratio to total shares (%) 4.23; conversion request period - start date September 17, 2026, end date August 17, 2028 13. Remaining face value (electronically registered amount) of the bonds after acquisition (KRW): - 14. Whether subject to Fair Trade Commission reporting: Not applicable 15. Other matters for investors' reference - Item 7 above, the "acquisition decision date," is the board resolution date, and item 8 above, the "scheduled payment date," indicates that payment and acquisition will occur a total of 4 times at 2-month intervals starting June 30, 2026. Withholding tax will be deducted from the interest portion of the repayment amount before payment. - Installment repayment details Installment | Date | Principal repaid | Interest repaid | Total payment 1st | 2026-06-30 | 700,000,000 | 16,626,960 | 716,626,960 2nd | 2026-09-15 | 1,000,000,000 | 30,172,260 | 1,030,172,260 3rd | 2026-10-31 | 1,000,000,000 | 34,075,130 | 1,034,075,130 4th | 2026-12-31 | 1,000,000,000 | 39,277,150 | 1,039,277,150 Total | - | 3,700,000,000 | 120,151,500 | 3,820,151,500 - Regarding item 11 above, the future handling plan: since acquiring these bonds before maturity, no separate discussion has taken place to date on a concrete handling plan. A final decision on resale or retirement will be made in the future through a board resolution. - Regarding item 12 above, matters concerning conversion: the conversion price as of the report date reflects an adjustment because, effective May 7, 2026, the Company's shares were consolidated 2-for-1 (from KRW 100 to KRW 200 par value), and the conversion price of these bonds was accordingly adjusted from 1,714 won to 3,428 won.

[Matters concerning the seller] Seller name | Relationship to the Company or largest shareholder | Basis for selection | Transactions/plans within 6 months before and after the acquisition decision | Face value of bonds sold (KRW) | Remarks ITEC Co., Ltd. (as stated in the filing) | - | Bondholder of these bonds | - | 3,700,000,000 | -

[Where the seller includes a corporation or organization] (1) Basic information on the corporation or organization Name | Number of investors (persons) | CEO (representative partner) | Managing partner | Largest shareholder (largest investor) - name, stake (%) ITEC Co., Ltd. | 8,940 | Lee Jang-hyeok | - | Choi Hyeon-sik, 10.69%

(2) Key financial matters of the corporation or organization for the most recent fiscal year (unit: KRW millions) Fiscal year: 2025, settlement month: December Total assets: 210,275; Revenue: 48,518; Total liabilities: 38,436; Net income (loss): -7,002; Total equity: 171,839; External auditor: Yeil Accounting Corporation; Capital stock: 11,697; Audit opinion: Unqualified