This is a routine administrative filing with no earnings or strategic news. The CFO's 600,000-share sale is notable but not alarming given the $49.9B market cap. Monitor the next 20-F or 6-K for any broader insider selling pattern or operational updates.
Price Chart
Executive Summary
UMC filed a routine 6-K reporting a subsidiary general manager change at United Semiconductor (Xiamen) and September 2026 insider trading data. CFO Chitung Liu sold 600,000 shares and VP JT Lin sold 10,000 shares during the month. No material financial data, guidance, or strategic announcements were included.
Key Facts
- Subsidiary United Semiconductor (Xiamen) appointed LO, CHING-SHU as new General Manager effective October 23, 2026, replacing TAN, WEN YI due to job relocation.
- CFO Chitung Liu reduced his shareholding from 2,112,917 to 1,512,917 shares (a decrease of 600,000 shares) during September 2026.
- VP JT Lin reduced his shareholding from 515,060 to 505,060 shares (a decrease of 10,000 shares) during September 2026.
- No pledges or pledge clearances were reported by directors, executive officers, or 10% shareholders for September 2026.
- No financial results, guidance, or material agreements were disclosed in this filing.
Financial Impact
No financial figures reported. Insider sales by CFO and VP are modest relative to total shares outstanding and do not indicate a material change in company fundamentals.
Risk Factors
- CFO selling 600,000 shares in a single month could signal personal portfolio diversification or reduced conviction, though the amount is small relative to market cap.
- No forward-looking guidance or operational metrics were provided, leaving the near-term outlook uncertain.
Market Snapshot
Investment Themes
Documents Analyzed
This report is based on 5 SEC documents filed with EDGAR.
| Document | Accession Number |
|---|---|
| 6-K Filing (Primary) | 0001193125-26-429369 |
| Document: umc-ex99.htm | 0001193125-26-429369 |
| Document: 0001193125-26-429369-index-headers.html | 0001193125-26-429369 |
| Document: 0001193125-26-429369-index.html | 0001193125-26-429369 |
| Document: 0001193125-26-429369.txt | 0001193125-26-429369 |
Filters
| Type | Now | ||||
|---|---|---|---|---|---|
Oct 23, 2026 4d ago | 6-K | $18.89 | awaiting T+5 | — | $19.45 (+2.96%) |
Oct 13, 2026 14d ago | 6-K | $22.39 $19.67 | ▼ −12.15% | ▼ −11.00% | $19.45 (−13.13%) |
Oct 7, 2026 21d ago | Court Ruling | $22.82 $20.92 | ▼ −8.33% | ▼ −8.05% | $19.45 (−14.77%) |
Oct 6, 2026 21d ago | 6-K | $23.19 $22.39 | ▼ −3.45% | ▼ −3.31% | $19.45 (−16.13%) |
Oct 5, 2026 22d ago | 6-K | $23.92 $22.55 | ▲ +5.73% | ▲ +6.15% | $19.45 (+18.69%) |
Sep 29, 2026 28d ago | 6-K | $24.72 $23.19 | ▼ −6.19% | ▼ −8.14% | $19.45 (−21.32%) |
Sep 22, 2026 5w ago | Insider Cluster | $25.77 $24.72 | ▲ +4.07% | ▲ +2.89% | $19.45 (+24.52%) |
Sep 4, 2026 7w ago | 6-K | $20.77 $21.90 | ▲ +5.44% | ▲ +6.65% | $19.45 (−6.36%) |
Sep 2, 2026 7w ago | 6-K | $19.97 $22.12 | ▲ +10.77% | ▲ +11.72% | $19.45 (−2.60%) |
Aug 26, 2026 8w ago | 6-K | $19.03 $19.97 | ▼ −4.94% | ▼ −5.06% | $19.45 (−2.21%) |
US Market Status
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