ASE Holding Announces Subsidiary USI's Investment in Shanghai Shangce Xingrongxin Private Equity Fund

Release Date: July 17, 2026 Statement Date: July 16, 2026 Statement Time: 19:40:44 Company Code: 3711 Company Name: ASE Holding Subject: Announcement on behalf of subsidiary Universal Scientific Industrial (USI) regarding investment in Shanghai Shangce Xingrongxin Private Equity Fund (Limited Partnership) Applicable Clause: Clause 24 Factual Date: July 16, 2026

Details:

1. Name and nature of the subject matter (if preferred shares, specify issuance terms such as dividend rate): Shanghai Shangce Xingrongxin Private Equity Fund (Limited Partnership)

2. Factual Date: 07/16/115

3. Number of trading units, unit price, and total transaction amount: Number of units and unit price: Not applicable Total transaction amount: Capital commitment of RMB 50,000,000.00 (approximately NT$234,560,000)

4. Counterparty and its relationship with the company (if the counterparty is an individual and not a related party of the company, name disclosure may be omitted): Counterparty: Shanghai Guoce Investment Management Co., Ltd. (serving as fund manager, general partner, and managing partner) Relationship with company: Not a related party of the company

5. If the counterparty is a related party, disclose the reason for selecting such party, the previous transferor, the relationship among the previous transferor, the company, and the counterparty, the previous transfer date, and amount: Not applicable

6. If the owner of the subject matter was a related party of the company within the past five years, disclose the related party’s acquisition and disposal date, price, and relationship with the company at the time: Not applicable

7. Matters related to the disposal of receivables (including types of collateral attached to disposed receivables; if receivables from related parties are disposed, disclose the name of the related party and the book value of receivables disposed): Not applicable

8. Gain (or loss) from disposal (not applicable for acquisition of securities) (if deferred, list and explain recognition): Not applicable

9. Delivery or payment terms (including payment periods and amounts), contractual restrictions, and other important agreements: Delivery or payment terms: Unless otherwise agreed in the contract or decided by the manager, contributions shall be paid in four installments at 30%, 30%, 20%, and 20%, in RMB cash. Contractual restrictions and other important agreements: As stipulated in the contract.

10. Decision-making method for this transaction, reference basis for price determination, and decision-making unit: According to the company’s authorized approval authority

11. Net asset value per share of the securities-issuing company acquired or disposed: Not applicable

12. Difference between private placement reference price and per-share transaction amount of the securities-issuing company exceeds 20%: Not applicable

13. Cumulative number, amount, ownership ratio, and rights restriction status (e.g., pledge) of the securities involved in this transaction (including this transaction) held to date: Number of transactions: Not applicable Amount: RMB 50,000,000.00 Ownership ratio: Approximately 7.98% Rights restriction status: None

14. Proportion of private securities investment (including this transaction) to total assets and equity attributable to owners of the parent company in the company’s latest financial statements, and the amount of working capital in the latest financial statements: Proportion to total assets: 0.11% Proportion to equity of parent company: 0.13% Working capital: -NTD 3,568,201 thousand

15. Manager and brokerage fees: None

16. Specific purpose or use of the acquisition or disposal: Long-term investment

17. Opinion of dissenting directors regarding this transaction: None

18. Whether this transaction is a related-party transaction: No

19. Board approval date: Not applicable

20. Supervisor approval or Audit Committee consent date: Not applicable

21. Whether the accountant issued an adverse opinion on this transaction: Not applicable

22. Name of accounting firm: Not applicable

23. Name of accountant: Not applicable

24. Accountant’s practice certificate number: Not applicable

25. Other disclosures: Information required to be disclosed by Universal Scientific Industrial (USI) under Shanghai Stock Exchange regulations regarding this transaction can be found on the Shanghai Stock Exchange website.