Key Highlights

  • United Microelectronics (NYSE:UMC) traded at USD 19.75 on October 21, 2026, up 0.41%, with a market value of USD 49.506 billion, a trailing P/E of 19.87 and a PEG of -1.69.
  • No company announcement dated October 21 was found; September sales were TWD 25.35 billion, up 27.22% from a year earlier, and August sales were TWD 25.04 billion, up 30.71%.
  • The quote is 31.8% below the 52-week high of USD 28.96, and published data shows a 9.7% fall to USD 23.72 on October 5, with no cause found.
  • Third quarter results are expected on October 28, 2026, and consensus is Hold, with a published target near USD 19.12, close to the current quote, so little upside is priced in.

Strong Sales, Weaker Shares

No company release dated October 21 was found. UMC reported September sales of TWD 25.35 billion, up 27.22% from a year earlier, and August sales of TWD 25.04 billion, up 30.71%, yet the receipts fell 9.7% to USD 23.72 on October 5, and no cause for that drop was found. The quote of USD 19.75 is about 16.7% below that level, simple arithmetic. A vice president sold 10,000 shares on September 23. Early-session volume was 1.148 million shares against a 3-month average of 12.202 million, so turnover was still building. The 52-week range is USD 6.97 to USD 28.96, so the stock has also more than doubled from its low, which makes the recent slide a pullback within a very large gain, simple arithmetic on two published figures. The sale by the executive was small.

What the Valuation Figures Show

A P/E of 19.87 sits just inside the 0 to 20 band and means investors pay about USD 19.87 for each USD 1 of trailing earnings. The PEG of -1.69 is negative, so the growth input is negative or unusable and says nothing about value. UMC is a Taiwan contract chipmaker that makes mature-node chips for others. Its sales are in New Taiwan dollars and its receipts trade in dollars, so currency swings add risk. Published data shows a dividend near USD 0.31, a yield of about 1.55%, and a consensus target near USD 19.12, close to the current quote. A Hold rating from analysts suggests they see limited upside from here.

Risks and What to Watch

Pricing pressure on mature chips, customer inventory cycles, Chinese competition and trade policy are the main risks for a foundry in Taiwan. Monthly sales growth above 27% shows demand, but the market's reaction on October 5 shows that investors worry about margins and outlook, and the filters cannot show that. Investors should watch the October 28 results for utilization rates, gross margin and guidance for the fourth quarter. Sales for October, usually published in early November, will show whether the strong run continued. Because the filters look at trailing numbers, they cannot say whether margins are holding, so the results call is the main source of evidence on profit.

Where Things Stand

No catalyst was found for United Microelectronics (NYSE:UMC) on October 21. Sales growth above 27% in August and September has not stopped the shares falling 31.8% from their high, and the cause of the October 5 drop is unknown. The P/E of 19.87 is just inside the filter band, and the negative PEG is unusable, so the filters show little about value. The next test is the October 28 report, where margins and guidance matter more than sales. This is not investment advice.