Q1 2026 Quarterly Report (32nd Fiscal Year)

Quarterly Report 6.5 TSE Co., Ltd. Quarterly Report (32nd Fiscal Year) Fiscal Year: January 1, 2026 to March 31, 2026 To: Financial Services Commission / Korea Exchange Date: May 15, 2026 Filing Entity Type: Listed Stock Corporation Exemption Reason: None Company Name: TSE Co., Ltd. Representative Directors: Kim Cheol-ho, Kim Myeong-jin Headquarters: 189 Gunsu 1-gil, Jiksan-eup, Seobuk-gu, Cheonan-si, Chungcheongnam-do Phone: 041-581-9955 Website: http://www.tse21.com Responsible Preparer: Vice President Tak Jeong (041-581-9955) Table of Contents [Confirmation by Representative Directors, etc.] I. Company Overview 1. Company Overview 1. Status of Consolidated Subsidiaries (Summary) (Unit: companies) - Listed: Beginning 3, Increase -, Decrease -, End 3 (Major subsidiaries: 2) - Unlisted: Beginning 7, Increase -, Decrease -, End 7 (Major subsidiaries: 1) - Total: Beginning 10, Increase -, Decrease -, End 10 (Major subsidiaries: 3) 1-1. Changes in Consolidated Companies: None (no new consolidations or de-consolidations). 2. Legal and Commercial Name The Company's name is TSE Co., Ltd. (English: TSE Co., Ltd., abbreviated TSE). 3. Date of Establishment and Duration The Company was established on August 31, 1995 with the primary business purpose of manufacturing and selling semiconductor inspection equipment and peripherals. It was listed via IPO on January 5, 2011. 4. Headquarters Address, Phone Number, and Website - TSE Co., Ltd.: 189 Gunsu 1-gil, Jiksan-eup, Seobuk-gu, Cheonan-si, Chungnam / 041-581-9955 / https://www.tse21.com - GM Test Co., Ltd.: 48 Seonggeo Sandan 1-ro, Seonggeo-eup, Seobuk-gu, Cheonan-si, Chungnam / 041-410-2652 / https://www.gmtest.com - Tiger Elec Co., Ltd.: 33 Yeomjeon-ro 187beon-gil, Nam-gu, Incheon (Dohwa-dong) / 032-579-4100 / https://www.tigerelec.com - Megatouch Co., Ltd.: 42 3-Gongdan 2-ro, Seobuk-gu, Cheonan-si, Chungnam / 041-412-7100 / https://www.megatouch.co.kr - Megasen Co., Ltd.: 7 Pungse Sandan-ro, Pungse-myeon, Dongnam-gu, Cheonan-si, Chungnam / 041-621-9030 / https://megasen.co.kr/ - LDT Co., Ltd. (*1): 126-33 Handeul 1-ro, Seobuk-gu, Cheonan-si, Chungnam (Baekseok-dong 1100) / 041-520-7300 / http://www.ldt.co.kr - Weihai Taisi Electronics Co., Ltd.: No.17 Hainan Road, Economic Technical Development Zone, Weihai, Shandong, China - TSE WORKS, INC.: 5700 Stoneridge Mall Rd Ste 310, Pleasanton, CA 94588 - MEGAELEC: Lot 031A, No 02, Road 7, VSIP Bac Ninh, Phu Chan Commune, Tu Son Town, Bac Ninh Province, Vietnam - TaiSi Technology: No. 1 Liufangyuanheng Road, Wuhan East Lake New Technology Development Zone, Wuhan, Hubei, China - Taisi Semicon (Hefei): Fanhua Avenue and Innovation in Taohua Industrial Park, Feixi County, Hefei, Anhui, China (*1) In December 2025, the Company participated in a third-party allocation capital increase of its affiliate LDT Co., Ltd., obtaining effective control and thereby including it as a consolidated subsidiary. 5. Legal Basis for Business Operations: Not applicable. 6. SME / Venture / Mid-sized Enterprise Status: - SME: Not applicable - Venture enterprise: Not applicable - Mid-sized enterprise: Applicable 7. Korean Agent (if any): Not applicable. 8. Major Business Activities 1) Parent Company: The Company manufactures and sells semiconductor and display inspection equipment, supplying inspection equipment to semiconductor and display panel manufacturers. Business purposes per the Articles of Incorporation include: (1) Manufacturing and sale of semiconductor inspection equipment and peripherals; (2) Operation of semiconductor inspection equipment and electronic control equipment; (3) Leasing of semiconductor inspection equipment; (4) Semiconductor manufacturing and sales; (5) Manufacturing and sale of electronic control equipment; (6) Real estate leasing; (7) All related businesses. 2) Major Subsidiaries: - Tiger Elec Co., Ltd.: PCB business; R&D on PCBs; import substitution of semiconductor PCBs; design development of semiconductor PCBs; import/export of high-multilayer PCBs; real estate leasing; related businesses. - Megatouch Co., Ltd.: Manufacturing and sale of semiconductor components; manufacturing and sale of PCBs; manufacturing/sale of electronic devices and components; import/export thereof; plating; related businesses. - GM Test Co., Ltd.: Test program development for semiconductor chips; test engineering services for chip development; electrical defect/characteristic analysis programs and engineering; mass-production test program development and testing; test engineering consulting; chip testing; semiconductor device design and IP business; semiconductor device packaging; device sales; semiconductor materials manufacturing/sale; semiconductor process equipment and parts manufacturing/sale/lease/related services; maintenance of semiconductor experimental equipment; test technology research lab operation; real estate trading/leasing; trading; e-commerce and mail-order sales; related businesses. 9. Credit Rating Recent 3-year credit ratings: - 2025.04.19: Corporate credit rating A- by E-Credible Co., Ltd. (AAA~D scale) - 2024.04.19: Corporate credit rating BBB+ by E-Credible - 2023.04.21: Corporate credit rating A- by E-Credible Credit Rating Definitions: AAA (highest debt service capacity) through D (currently in default), with intermediate grades AA, A, BBB, BB, B, CCC, CC, C. 10. Stock Listing and Special Listing Information - Listing Status: Listed on KOSDAQ - Listing Date: January 5, 2011 - Special Listing Type: Not applicable 2. Corporate History 1. TSE Co., Ltd. (Parent Company): [details follow] [Translation truncated]