H1 2026 Semi-Annual Report (26th Fiscal Term, Jan–Jun 2026) — ISC

Summary

ISC Co., Ltd. filed its 26th-term semi-annual report covering January 1 through June 30, 2026. The company's core business remains the design and manufacture of semiconductor test sockets (silicon rubber contactors) and spring contact probes, with three unchanged consolidated subsidiaries in the US, Vietnam, and Hong Kong. The AA credit rating from iCredible has been maintained consecutively since at least 2020, signaling stable financial health. Total issued shares stand at 21,197,058 with 54,607 treasury shares (0.3%), partly attributable to the 1st and 2nd series exchangeable bonds converted as of April 1, 2026 — details of which appear in the truncated portion of the filing. No changes to the consolidated group or capital structure were reported during the period.

Historical Impact

1 past Semi-Annual Report · ≈ 10-Q event at ISC

Median +5d

-11.02%

Range

-11.02% to -11.02%

Positive outcomes

0/1

Filed	P₀	P₊₅	+5d
Aug 14, 2025	₩64,400	₩57,300	-11.02%

Past performance does not guarantee future results. Small sample sizes may not be representative. For informational purposes only.

Full Translation

SEMI-ANNUAL REPORT 6.7 ISC Co., Ltd. Y 131111-0057876 SEMI-ANNUAL REPORT (26th Term) Fiscal Year: January 1, 2026 to June 30, 2026 To: Financial Services Commission / Korea Exchange Date of Submission: August 14, 2026 Type of Reporting Entity: Listed equity company Exemption grounds: None applicable Company Name: ISC Co., Ltd. Representative Director: Kim Jeong-ryeol Headquarters: 26, Geumto-ro 40beon-gil, Sujeong-gu, Seongnam-si, Gyeonggi-do (Geumto-dong) Telephone: 031-777-7675 Website: http://isc21.kr Prepared by: Finance Director — Lee Jae-seung Telephone: 031-777-7675 TABLE OF CONTENTS [Confirmation by CEO, etc.] I. COMPANY OVERVIEW 1. Company Overview a. Legal and Commercial Name The company's name is 'ISC Co., Ltd.' (주식회사 아이에스시 in Korean) and 'ISC Co., Ltd.' in English. As of the report date, consolidated subsidiaries are: ISC International INC, ISC VINA MANUFACTURING COMPANY LIMITED, and TechDream Co., Limited. b. Date of Incorporation and Duration The company was incorporated on February 22, 2001, with the primary business purpose of manufacturing test socket products — key consumable components used in back-end semiconductor and electronic component inspection equipment. Its shares have been listed on the KOSDAQ market since October 1, 2007. c. Headquarters Address, Telephone, and Website - ISC Co., Ltd. Address: 26, Geumto-ro 40beon-gil, Sujeong-gu, Seongnam-si, Gyeonggi-do (Geumto-dong) Tel: 031-777-7675 Website: http://www.isc21.kr - ISC International, INC Address: 5201 Great America Parkway 446, Santa Clara, CA, USA - ISC VINA MANUFACTURING COMPANY LIMITED Address: LOT A12-2, Ba Thien 2 Industrial Zone, Vinh Phuc Province, Hanoi, Vietnam - TechDream Co., Limited Address: Flat/RM 701, 7F, Tower 2, Silvercord, 30 Canton Road, Tsim Sha Tsui, Kowloon, Hong Kong, China d. Principal Business Activities The company supplies semiconductor and ICT total solutions, including the world's first commercially mass-produced silicon rubber test socket (Silicone Rubber Contactor: iSC) and test probe (Spring Contact Probe: iSP). For further details, refer to Section II (Business Overview) and Section IX (Affiliated Companies) of this report. e. Credit Ratings | Date | Instrument | Rating | Agency (Scale) | Type | |------------|--------------------------|--------|------------------------|------| | 2025-04-24 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2024-04-24 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2023-04-27 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2022-04-21 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2021-10-05 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2021-04-24 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2020-09-23 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | | 2020-04-09 | Credit / Cash Flow Grade | AA | iCredible (AAA ~ D) | — | Note: The above ratings apply to ISC Co., Ltd. only; no credit ratings exist for subsidiaries. iCredible Credit Rating Definitions: | Rating | Definition | Cumulative Distribution | |--------|------------|-------------------------| | AAA | Highest debt repayment capability | 0.01% | | AA+/AA/AA- | Very high capability, marginally inferior to AAA | 0.05% | | A+/A/A- | High capability, more susceptible to economic downturns than higher grades | 0.5% | | BBB+/BBB/BBB- | Adequate capability, but potential for deterioration under adverse conditions | 12% | | BB+/BB/BB- | No current issue, but speculative elements exist under adverse market conditions | 40% | | B+/B/B- | Repayment capability exists, but speculative risk of default in adverse environment | 83% | | CCC+/CCC/CCC- | High likelihood of default; highly speculative | 92% | | CC | High probability of default | 94% | | C | Very high probability of default | 98% | | D | Currently in default | 100% | | NCR | Rating cancelled/suspended due to fraudulent conduct | — | Cash Flow Rating Definitions: | Grade | Definition | |-------|------------| | A (CR-1) | Cash generation capability very strong and stable | | B (CR-2) | Cash generation capability good, but stability slightly inferior to A | | C+ (CR-3) | Above-average cash generation; some risk of decline under adverse conditions | | C- (CR-4) | Average cash generation; risk of decline under adverse conditions | | D (CR-5) | Low cash generation or weak repayment ability relative to total borrowings | | E (CR-6) | Negligible cash generation; very poor repayment ability | | NF | Insufficient or unreliable financial statements | | NR | Less than 3 years of financial statements available | 1. Overview of Consolidated Subsidiaries Consolidated Subsidiaries Summary (Unit: companies) | Category | Beginning | Increase | Decrease | End | Listed | Non-listed | |--------------|-----------|----------|----------|-----|--------|------------| | Non-listed | 3 | — | — | 3 | — | — | | Total | 3 | — | — | 3 | — | — | ※ For details, refer to Detailed Table 1: Status of Consolidated Subsidiaries. 1-1. Changes in Consolidated Entities | Category | Subsidiary | Reason | |--------------------|------------|--------| | Newly consolidated | — | — | | Deconsolidated | — | — | SME / Venture / Mid-sized Enterprise Classification: - SME: Not applicable - Venture: Not applicable - Mid-sized Enterprise: Not applicable Stock Listing Details: | Market | Listing Date | Special Listing Type | |-------------|-------------------|------------------------| | KOSDAQ | October 1, 2007 | Not applicable | 2. Company History Per disclosure format guidelines, company history is omitted from semi-annual reports. Please refer to the 25th Annual Business Report submitted on March 18, 2026. 3. Changes in Paid-in Capital Per disclosure format guidelines, this section is omitted from semi-annual reports. Please refer to the 25th Annual Business Report submitted on March 18, 2026. 4. Total Number of Shares Share Count Summary (As of June 30, 2026) (Unit: shares, %) | Category | Common Shares | Total | |------------------------------------------------|---------------|-------------| | I. Authorized shares | 40,000,000 | 40,000,000 | | II. Total shares ever issued | 21,197,058 | 21,197,058 | | III. Total shares retired | — | — | | 1. Capital reduction | — | — | | 2. Profit-funded cancellation | — | — | | 3. Redemption of redeemable shares | — | — | | 4. Other | — | — | | IV. Total issued shares (II – III) | 21,197,058 | 21,197,058 | | V. Treasury shares | 54,607 | 54,607 | | VI. Floating shares (IV – V) | 21,142,451 | 21,142,451 | | VII. Treasury share ratio | 0.3% | 0.3% | Note: The treasury share count reflects, as of April 1, 2026, shares related to the 1st and 2nd series exchangeable bond principal — [Translation truncated]