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Exhibit

Exhibit Description

99.1 Announcement on 2023/11/07: To clarify news reported by Commercial Times on November 7, 2023

99.2 Announcement on 2023/11/09: To announce the registration of capital reduction due to cancellation of the RSA

99.3 Announcement on 2023/11/16: UMC will attend investor conferences on 2023/11/22

99.4 Announcement on 2023/11/06: October Revenue

99.5 Announcement on 2023/11/10: the trading and pledge of UMC common shares by directors, executive officers and 10% shareholders of UMC 1. Date of occurrence of the event: 2023/11/07

Exhibit 99.1

To clarify news reported by Commercial Times on November 7, 2023

2. Company name: UNITED MICROELECTRONICS CORP.

3. Relationship with the Company (please enter “the company itself” or “subsidiaries”): the company itself

4. Reciprocal shareholding percentage: N/A

5. Name of the reporting media: Commercial Times, A14

6. Content of the report: Expected to return to double-digit growth in 2024

7. Cause of occurrence:

UMC did not announce any revenue forecast. Regarding to the Company’s financial and operating results, please refer to the public notice on MOPS.

8. Countermeasures: None

9. Any other matters that need to be specified: None 1. Date of the competent authority’s approval of capital reduction: 2023/11/08

Exhibit 99.2

To announce the registration of capital reduction due to cancellation of the RSA

2. Date of completion of capitalization change registration: 2023/11/08

3. Effect on the financial statements (including any discrepancy between the amount of paid-in capital and the no. of shares outstanding, and the effect on net worth per share):

(1) Before the capital reduction: The paid-in capital is NT$125,031,392,410; the shares outstanding are 12,503,139,241 shares; book value per share is NT$27.97

(2) After the capital reduction: The paid-in capital is NT$125,030,946,600; the shares outstanding are 12,503,094,660 shares; book value per share is NT$27.97

(Note: Net worth per share was calculated based on the consolidated financial statements for the third quarter of 2023 reviewed by CPA.)

4. Plan for expected share replacement operations: NA

5. Estimated no. of listed common shares after capital reduction and new issue: NA

6. Estimated no. of listed common shares as a percentage of issued common shares after capital reduction and new issue (No. of common shares after capital reduction/No. of issued common shares): NA

7. Countermeasures for poor circulation of equity if the aforesaid estimated no. of listed common shares does not reach 60 million shares and the percentage does not reach 25% after capital reduction: NA

8. Any other matters that need to be specified: None 1. Date of institutional investor conference: 2023/11/22

Exhibit 99.3

UMC will attend investor conferences on 2023/11/22

2. Time of institutional investor conference: 02:00 PM

3. Location of institutional investor conference: W Hotel Taipei

4. Outline of institutional investor conference:

The Company will attend the “Taiwan Corporate Day”, held by Citi.

5. Any other matters that need to be specified: None This is to report the changes or status of 1) Sales volume, 2) Funds lent to other parties, 3) Endorsements and guarantees, and 4) Financial derivative transactions for the period of October 2023.

Exhibit 99.4

United Microelectronics Corporation

November 6, 2023

a Not under hedging accounting: NT$ thousand

UMC

Exhibit 99.5

United Microelectronics Corporation

For the month of October, 2023

This is to report 1) the trading of directors, executive officers and 10% shareholders of United Microelectronics Corporation (“UMC”) (NYSE: UMC); 2) the pledge and clear of pledge of UMC common shares by directors, executive officers and 10% shareholders of UMC;