Chairman Kwak Dong-Shin Files Plan to Purchase 2,870 Shares via Open Market

Report on Trading Plan for Specific Securities by Executive / Major Shareholder To: Financial Services Commission (Securities and Futures Commission) To: Korea Exchange Trading Start Date (Settlement Date): October 12, 2026 Date Obligation to Report Arose: September 9, 2026 Report Preparation Base Date: September 9, 2026 ※ The reporter confirms that the trading plan for specific securities as of the report preparation base date has been accurately prepared in accordance with relevant laws and disclosure guidelines, and that there are no false statements or omissions of material facts. Reporter: Kwak Dong-Shin, Chairman of Hanmi Semiconductor 1. Information on the Issuing Company Company Name: Hanmi Semiconductor Co., Ltd. Corporate Classification: Listed on the Korea Stock Exchange (KOSPI) Company Code: 042700 Total Issued Shares: 95,312,200 2. Information on the Reporter Reporter Classification: Individual (Domestic) Name (Korean): 곽 동 신 Name (Chinese/English): 郭 東 信 / Kwak, Dong-Shin Date of Birth: December 17, 1974 Address (district level): Hannam-dong, Yongsan-gu, Seoul Relationship with Issuing Company: Executive (Registered Director) Title: Chairman of Hanmi Semiconductor Appointment Date: March 16, 2007 Retirement Date: — Major Shareholder Status: De facto controlling shareholder Contact: IR & PR Department, Hanmi Semiconductor Co., Ltd. Department Manager: Cho Jae-hoon (Deputy) Phone: 032-580-1507 / Fax: 032-578-5557 Email: 2021089@hanmisemi.com 3. Ownership Status and Trading Plan for Specific Securities a. Ownership Status at Time of Trading Plan Submission Common Shares: 32,048,145 shares — 33.62% of total issued shares (No holdings in warrants, convertible bonds, bonds with warrants, participating bonds, exchangeable bonds, depositary receipts, or other instruments) Total specific securities: 32,048,145 shares (33.62%) Total Issued Shares (J): 95,312,200 b. Detailed Transactions in the Six Months Prior to Trading Start Date - April 29, 2026: Open-market purchase, 9,576 common shares @ ₩315,407/share = ₩3,020,342,000 - June 18, 2026: Open-market purchase, 23,657 common shares @ ₩338,917/share = ₩8,017,769,000 - August 3, 2026: Open-market purchase, 29,336 common shares @ ₩170,566/share = ₩5,003,711,800 Total prior 6-month purchases: 62,569 shares / ₩16,041,822,800 c. Trading Plan (1) Purpose: To enhance corporate value through direct acquisition of company shares (self-investment in own shares) (2) Transaction Volume and Amount Trading Start Date (Settlement): October 12, 2026 Trading End Date (Settlement): October 12, 2026 Trading Period: 1 day Method: Open-market purchase Security Type: Common shares Number of Shares: 2,870 Expected Price per Share: ₩244,500 Expected Transaction Amount: ₩701,715,000 ※ The number of shares (①) and price per share (②) represent the reporter's estimated quantity and price. Pursuant to Article 173-3(3) of the Capital Markets Act, the reporter may deviate from the plan within 70–130% of the planned transaction amount (③ = price × quantity); actual price and quantity may therefore differ. (3) Basis for Price Calculation Security Type: Common shares Price: ₩244,500 Basis: Closing price on September 8, 2026 (the trading day immediately preceding the report preparation base date) (4) Contracts Related to Planned Transactions: None d. Assessment of Transaction Scale Prior 6-month cumulative transactions: 62,569 shares / ₩16,041,822,800 Planned transaction: 2,870 shares / ₩701,715,000 Combined total: 65,439 shares / ₩16,743,537,800 Combined trading ratio relative to total issued shares: 0.07% e. Expected Ownership After Completion of Trading Plan Common Shares: 32,051,015 shares — 33.63% of total issued shares (No holdings in any other specific securities instruments) Total Issued Shares (J): 95,312,200 Expected ownership ratio: 33.63%