Large Shareholding Change: Collateral Pledge Released After Related-Party Loan Repayment

REPORT ON LARGE SHAREHOLDING STATUS OF STOCKS, ETC. (GENERAL) To: Financial Services Commission To: Korea Exchange Date obligation to report arose: July 31, 2026 Report preparation reference date: August 6, 2026 Reporter: Koo Bon-cheon (구본천) [SUMMARY INFORMATION] Issuing Company Name: LB Semicon Co., Ltd. (엘비세미콘(주)) Relationship with Issuing Company: Largest Shareholder Report Classification: Change Number of Shares Held and Holding Ratio: Shares Held Ratio (%) Previous Report: 19,088,153 31.11 Current Report: 19,088,153 31.11 Shares Subject to Major Contracts: Shares Ratio (%) Previous Report: 4,161,169 7.16 Current Report: 926,000 1.59 Voting Rights Held: Voting Rights Ratio (%) Previous Report: — — Current Report: — — Voting Rights Subject to Major Contracts: Voting Rights Ratio (%) Previous Report: — — Current Report: — — Reason for Report: Change in collateral agreement due to repayment of loan by special related party (cancellation of pledge/lien setting) ※ The reporter confirms that the shareholding status of the reporter and special related parties as of the report preparation reference date has been accurately prepared in accordance with relevant laws and regulations, and that there are no false statements or omissions of material facts. PART 1: OVERVIEW OF REPORT 1. Details of the Issuing Company Company Name: LB Semicon Co., Ltd. (엘비세미콘(주)) Company Code: 061970 Corporate Classification: KOSDAQ-listed corporation Total Number of Shares Issued with Voting Rights: 58,083,006 shares 2. Details of the Large Holder A. Reporter (1) Reporter Overview Report Classification: Change Joint Report: No Reporter Type: Individual (Domestic) Nationality: Republic of Korea Name (Korean): 구본천 Name (Hanja/English): 具本天 Address (up to dong/eup/myeon level): Cheongdam-dong, Gangnam-gu, Seoul Date of Birth or Business Registration No.: 640511 Occupation (Business Content): Registered Executive of LB Semicon Co., Ltd. Relationship with Issuing Company: Executive (Registered) Contact Information: Affiliated Company: LB Semicon Co., Ltd. Department: Planning Team Title: Senior Manager Phone: 031-68****** Name: Han Sun-gwang (한순광) Fax: 031-68****** Email: ******1@lbsemicon.com (2) Specific Details of the Reporter (applicable only for corporations, other organizations, statutory partnerships, and civil partnerships): N/A — All fields blank as reporter is an individual. B. Special Related Parties (1) Overview of Special Related Parties No. | Name | Type | Specific Relationship | DOB/Reg. No. | Nationality | Address | Occupation | Relationship w/ Company 1 | LB Co., Ltd. (㈜엘비) | Domestic Corp. | Affiliated company | 120-87-62897 | Korea | Daechi-dong, Gangnam-gu, Seoul | Holding company | Affiliated company 2 | Koo Bon-wan (구본완) | Individual (Dom.) | Relative | 661030 | Korea | Hannam-dong, Gangnam-gu, Seoul | — | Shareholder 3 | Koo Sang-mo (구상모) | Individual (Dom.) | Relative | 010317 | Korea | Cheongdam-dong, Gangnam-gu, Seoul | — | Shareholder 4 | Koo In-mo (구인모) | Individual (Dom.) | Relative | 030830 | Korea | Hannam-dong, Yongsan-gu, Seoul | — | Shareholder 5 | Lee Seong-eun (이성은) | Individual (Dom.) | Relative | 690330 | Korea | Cheongdam-dong, Gangnam-gu, Seoul | — | Shareholder 6 | Koo Hye-ran (구혜란) | Individual (Dom.) | Relative | 601231 | Korea | Daechi-dong, Gangnam-gu, Seoul | — | Shareholder 7 | Park Seong-eun (박성은) | Individual (Dom.) | Relative | 691014 | Korea | Hannam-dong, Yongsan-gu, Seoul | — | Shareholder 8 | Koo Hye-seon (구혜선) | Individual (Dom.) | Relative | 620505 | Korea | Bundang-gu, Seongnam-si, Gyeonggi | — | Shareholder 9 | Koo Jin-yeong (구진영) | Individual (Dom.) | Relative | 940305 | Korea | Cheongdam-dong, Gangnam-gu, Seoul | — | Shareholder 10 | Koo Ha-yeong (구하영) | Individual (Dom.) | Relative | 960917 | Korea | Cheongdam-dong, Gangnam-gu, Seoul | — | Shareholder 11 | Sim Yun-seon (심윤선) | Individual (Dom.) | Relative | 831219 | Korea | Daechi-dong, Gangnam-gu, Seoul | — | Shareholder 12 | Jang Yun-jeong (장윤정) | Individual (Dom.) | Relative | 881214 | Korea | Bundang-gu, Seongnam-si, Gyeonggi | — | Shareholder 13 | Koo Do-yeon (구도연) | Individual (Dom.) | Relative | 120629 | Korea | Hannam-dong, Yongsan-gu, Seoul | — | Shareholder * Addresses recorded only up to dong/eup/myeon level. (2) Specific Details of Special Related Parties (corporations) ① LB Co., Ltd. (㈜엘비) (Unit: KRW millions) Legal nature: Stock company Total assets (or total managed assets): 227,853 Total liabilities: 21,399 Total equity: 161,049 Capital stock: 1,000 Representative(s): Koo Bon-cheon, Kim Yun-gwon Decision-making body: General meeting of shareholders and Board of Directors Largest shareholder: Koo Bon-cheon Largest shareholder's stake (%): 28.27 C. Collective Investment Business Operator: N/A 3. Number of Shares Held and Holding Ratio Report Reference Date | Reporter | No. of Special Related Parties | Total Shares (shares) | Ratio (%) | Voting Shares (shares) | Ratio (%) | Total Voting Shares Issued Previous Report (2026-07-22) | Koo Bon-cheon | 14 | 19,088,153 | 31.11 | 15,819,778 | 27.24 | 58,083,006 Current Report (2026-08-06) | Koo Bon-cheon | 14 | 19,088,153 | 31.11 | 15,819,778 | 27.24 | 58,083,006 Change: 0 | 0 | 0 | 0 | 0 4. Purpose of Holding Purpose: Influence over management The reporter intends to make decisions in accordance with the company's management objectives regarding the following matters set forth in Article 154, Paragraph 1 of the Enforcement Decree of the Financial Investment Services and Capital Markets Act, should any of the following events arise in connection with the company's business operations: 1. Appointment or dismissal of executives, or suspension of their duties 2. Amendment of the articles of incorporation related to the board of directors and other corporate bodies 3. Changes in the company's capital 4. [Deleted] 5. Merger, division, or division-merger of the company 6. Comprehensive share exchange and share transfer 7. Transfer or acquisition of all or a material part (as designated by the FSC) of the business 8. Disposal of all assets or a material part (as designated by the FSC) 9. Lease of all operations, management entrustment, contracts sharing all profits and losses with a third party, or conclusion, modification, or termination of equivalent contracts 10. Dissolution of the company 5. Reason for Change Method of change: — Reason for change in shares: — Reason for change in terms: Change in collateral agreement due to repayment of loan by special related party (cancellation of pledge/lien setting) PART 2: DETAILS OF LARGE SHAREHOLDING 1. Shareholding Details by Reporter and Special Related Parties A. Shareholding Details by Type of Securities Relationship | Name | DOB/Reg. No. | Common Shares (w/ voting rights) | Shares | Ratio(%) | [other security types all zero] | Total Shares | Total Ratio(%) Reporter | Koo Bon-cheon | 640511 | 4,452,789 | — | — | — | 4,452,789 | 7.26 Special Related Party | LB Co., Ltd. (㈜엘비) | 120-87-62897 | 4,826,120 shares + CBs convertible to 3,268,375 shares | — | — | — | 8,094,495 | 13.19 Special Related Party | Koo Bon-wan | 661030 | 3,189,842 | — | — | — | 3,189,842 | 5.20 Special Related Party | Koo Sang-mo | 010317 | 729,480 | — | — | — | 729,480 | 1.19 Special Related Party | Koo In-mo | 030830 | 733,656 | — | — | — | 733,656 | 1.20 Special Related Party | Lee Seong-eun| 690330 | 817,530 | — | — | — | 817,530 | 1.33 Special Related Party | Koo Hye-ran | 601231 | 192,200 | — | — | — | 192,200 | 0.31 Special Related Party | Park Seong-eun| 691014 | — | — | — | — | — | — Special Related Party | Koo Hye-seon | 620505 | 89,327 | — | — | — | 89,327 | 0.15 Special Related Party | Koo Jin-yeong| 940305 | 366,961 | — | — | — | 366,961 | 0.60 [Translation truncated — source disclosure content ends here]