United Microelectronics Corp
UMC- Exchange
- NYSE
- Industry
- Semiconductors & Related Devices
- SEC CIK
- 0001033767
No open-market purchases or sales by United Microelectronics Corp insiders were filed in the last 90 days; 365 institutions reported holding it in 13F filings for Q2 2026, worth $4.89B in total; Maverick Capital is the only superinvestor holding it.
Holders of 5% or more of UMC
Holders whose latest Schedule 13D or 13G filing reports 5% or more of United Microelectronics Corp, largest stake first. The change is against the holder's previous filing.
| Holder | Latest form | Stake | Change | First filed | Latest filing | Filing |
|---|---|---|---|---|---|---|
| BlackRock, Inc. | 13G/A | 6.50%817.5M shares | – | Apr 29, 20261 filing | Apr 29, 2026 | SEC |
Stakes are as of each holder's latest filing. Holders whose last filing was in the old format (before December 18, 2024) have no stake on record and are not listed, and after an acquisition or delisting holders usually stop filing.
13D and 13G filings
1 Schedule 13D or 13G filing on United Microelectronics Corp, newest first, including old-format filings without a stake.
| Filed (ET) | Filer | Form | Stake | Change | Event date | Filing |
|---|---|---|---|---|---|---|
| Apr 29, 202611:21 AM ET | BlackRock, Inc. | 13G/A | 6.50%817.5M shares | – | Mar 31, 2026 | SEC |
Form 144: proposed insider sales
Notices from officers, directors and other affiliates planning to sell United Microelectronics Corp shares.
No Form 144 notices for United Microelectronics Corp are on file.