Treasury share acquisition: results report

What happened

Treasury Share Acquisition: Results Report 6.0 Omnisystem Co., Ltd.

To the Governor of the Financial Supervisory Service August 21, 2026

Company name: Omnisystem Co., Ltd. Representative Director: Park Hye-rin Head office address: 284 Yeonsam-ro, Ganam-eup, Yeoju-si, Gyeonggi-do (Phone) 031-883-5400 (Website) http://www.omnisystem.co.kr Preparer: (Title) Vice Chairman (Name) Yoon Ho-kwon (Phone) 031-883-5400

1. Name and address of the issuer a. Name: Omnisystem Co., Ltd. b. Address: 284 Yeonsam-ro, Ganam-eup, Yeoju-si, Gyeonggi-do

2. Matters concerning the acquisition report a. Filing date of the material event report: July 21, 2026 b. Acquisition period: July 23, 2026 to August 19, 2026 (dates based on trade execution date)

3. Acquisition details (unit: KRW, shares), Date: order quantity, acquired quantity, price per share, total acquisition value, brokerage firm, financial investment business ID: 2026.07.23: common shares, order 150,000, acquired 150,000, price 913, total 136,926,397, Daishin Securities, 00110893 2026.07.24: common shares, order 150,000, acquired 150,000, price 779, total 116,861,463, Daishin Securities, 00110893 2026.07.27: common shares, order 210,000, acquired 210,000, price 906, total 190,253,621, Daishin Securities, 00110893 2026.07.28: common shares, order 210,000, acquired 210,000, price 941, total 197,594,070, Daishin Securities, 00110893 2026.07.29: common shares, order 210,000, acquired 210,000, price 925, total 194,354,689, Daishin Securities, 00110893 2026.07.30: common shares, order 210,000, acquired 210,000, price 894, total 187,712,148, Daishin Securities, 00110893 2026.07.31: common shares, order 210,000, acquired 210,000, price 864, total 181,416,953, Daishin Securities, 00110893 2026.08.06: common shares, order 200,000, acquired 200,000, price 827, total 165,356,278, Daishin Securities, 00110893 2026.08.07: common shares, order 210,000, acquired 210,000, price 851, total 178,760,345, Daishin Securities, 00110893 2026.08.10: common shares, order 210,000, acquired 210,000, price 864, total 181,471,591, Daishin Securities, 00110893 2026.08.11: common shares, order 200,000, acquired 200,000, price 926, total 185,141,430, Daishin Securities, 00110893 2026.08.12: common shares, order 80,000, acquired 80,000, price 852, total 68,157,763, Daishin Securities, 00110893 2026.08.13: common shares, order 19,000, acquired 19,000, price 692, total 13,155,861, Daishin Securities, 00110893 2026.08.14: common shares, order 3,500, acquired 3,500, price 704, total 2,464,791, Daishin Securities, 00110893 2026.08.18: common shares, order 532, acquired 532, price 689, total 366,548, Daishin Securities, 00110893 2026.08.19: common shares, order 8, acquired 8, price 680, total 5,440, Daishin Securities, 00110893 Total: order 2,273,040; acquired 2,273,040; average price 880; total acquisition value 1,999,999,388 - The dates above are based on trade execution date. "Price per share" and "total acquisition value" exclude brokerage fees.

4. Whether the planned and actual acquisition amounts match Planned acquisition amount (KRW): common shares 2,000,000,000; other shares - Total acquisition value (KRW): common shares 1,999,999,388; other shares - Shortfall from planned amount: None Reason if shortfall occurred: - Note: The Company completed the acquisition as close as possible to the planned amount stated in the material event report; the small difference between the total acquisition value and the planned amount reflects a fraction of one share's price. Due to share-price fluctuations during the acquisition period, the planned quantity (2,176,278 shares) differed from the actual quantity acquired (2,273,040 shares).

5. Treasury share holdings after acquisition (as of August 21, 2026) (unit: KRW, shares, %) Holdings under Article 165-3 (A): common shares 4,665,507 shares, 7.86%, total value KRW 4,003,999,744 Holdings under trust contracts per Article 165-3 (B): - Total (A+B): common shares 4,665,507 shares, 7.86%, KRW 4,003,999,744 - "Total value" and "amount" above are book values including fees.

6. Changes in the largest shareholder's holdings before and after acquisition (as of August 21, 2026) (unit: shares) BIOSMART Co., Ltd.: common shares, holdings before 16,342,962, holdings after 20,107,269, reason for change: on-market purchase Total: common shares, 16,342,962 before, 20,107,269 after; other shares none; combined total 16,342,962 before, 20,107,269 after