Bernstein maintains UMC Underperform: high expectations built on weak assumptions

Overview

In this Asia Semiconductors & Global Memory report, Bernstein updated its models for UMC, Vanguard, and Novatek. The core conclusion is that the sharp share-price gains in UMC and Vanguard reflect high expectations for mature-node price hikes, demand spillover from TSMC's capacity exit, potential cooperation with Intel, and silicon photonics opportunities, but the report argues that most of these expectations are built on insufficient or weak assumptions. UMC is maintained at Underperform, while Vanguard and Novatek remain Market-Perform.

Core views

The report is most cautious on UMC. UMC is up about 150% since the start of the year, but channel checks show that 2H26 price increases are only in the high-single-digit range, which is hard to justify such a large stock move. Potential spillover demand from TSMC exiting Fab 2 and Fab 5 is limited in scale, and TSMC is still expanding mature-node capacity in Japan and Europe. UMC's silicon photonics business is still at an early stage and may take years to reach a scale large enough to affect company performance; even if discussions exist around cooperation with Intel at 3nm, execution would be difficult because UMC lacks 7nm/5nm experience and a customer base, and Intel's 3nm process would need to become more foundry-friendly. Vanguard looks relatively better, mainly because power management products account for a high share of revenue and TSMC interposer outsourcing should help VSMC improve profitability faster; Novatek, meanwhile, is benefiting from SoC demand driven by edge AI video applications, but high memory costs could cause end-demand destruction and order cuts in 4Q26.

Analysis framework

The report evaluates UMC, Vanguard, and Novatek using company model updates, valuation multiples, historical valuation comparisons, ROE/P/B correlations, channel checks, capacity spillover calculations, ASP and utilization assumptions, depreciation and expense assumptions, and comparisons with market consensus expectations. UMC is valued using target P/B, Vanguard using target P/B, and Novatek using target P/E.

Methodology notes

• Valuation methodsP/B-ROE valuation framework

  Set target P/B based on the historical correlation between P/B and ROE

  UMC's target P/B was raised from 1.5x to 2.5x, based on expected ROE improvement in 2026–2028 and the historical correlation between P/B and ROE; Vanguard's target P/B was raised from 3x to 4x, reflecting improved visibility for VSMC and the pricing outlook for 8-inch power management products.

• Valuation methodsP/E valuation framework

  Apply target P/E to forward Q5-Q8 EPS

  Novatek's NT$480.00 target price is based on Q5-Q8 EPS of NT$34 and a 14x target P/E; TSMC's NT$2,780 target price is based on Q5-Q8 EPS of NT$139 and a 20x P/E.

• industry_analysiscapacity spillover calculation

  Estimate the potential impact of TSMC Fab 2 and Fab 5 exits on UMC and Vanguard capacity

  Even if all demand from TSMC Fab 2 and Fab 5 flows to UMC and Vanguard, it would only equal 8–13% of their combined non-12-inch capacity, or 4–6% of total capacity; based on this, the report argues that spillover demand is unlikely to materially change fundamentals.

Asset mapping & comparison

Structured mapping from thesis to named assets (strengths, weaknesses, peers, risks).

• UMC.US / 2303.TT

  primary covered company; mature-node wafer foundry

  Strengths

  Higher ASP and utilization assumptions, with revenue expected to grow 16% and 15% in 2026 and 2027, respectively; greater 22nm contribution should help improve gross margin and operating margin; silicon photonics and CPO may provide long-term optionality.

  Weaknesses

  The stock has already risen sharply and valuation remains high; TSMC spillover demand is limited; mature-node demand is not strong; lacking 7nm and 5nm experience and customer base, Intel 3nm cooperation is unlikely to generate meaningful financial benefit.

  Comparison

  The report believes UMC is in a weaker position than Vanguard because Vanguard has a high revenue share from power management products and benefits from TSMC interposer outsourcing support; UMC's valuation remains above the peak during the COVID supply shortage period.

  Risks

  Upside risks include better-than-expected 28nm progress or pricing, stronger-than-expected end-demand recovery, and lighter-than-expected competitive pressure from China; downside pressure comes from valuation compression, falling mature-node prices, and Chinese competition.

• Vanguard International Semiconductor Corp / 5347.TT

  peer company under the same theme; mature-node and power management-related foundry

  Strengths

  More than 75% of revenue comes from power management products; TSMC interposer outsourcing improves VSMC demand visibility; VSMC phase-one 44KWPM capacity has already been locked in by long-term agreements, with mass production planned for 1Q27.

  Weaknesses

  The stock has also risen about 65% since the start of the year; VSMC depreciation will begin in 4Q26 and rise in 2027 and 2028; the report still sees about 7% potential downside.

  Comparison

  Better than UMC, because power management ICs and CMOS image sensors are exceptions in a backdrop of weak mature-node demand.

  Risks

  Risks include the pace of Singapore fab integration and cost reduction, driver IC demand and migration to 12-inch wafers, FX fluctuations, and changes in China's semiconductor support policies.

• Novatek Microelectronics Corp / 3034.TT

  company covered in the same report; display driver IC and SoC company

  Strengths

  Edge AI video, AI surveillance, and machine vision applications are becoming new growth drivers for SoC; the company can pass through higher memory costs via price increases; a higher SoC mix helps gross margin.

  Weaknesses

  High memory costs may lead to end-demand destruction and trigger order cuts in 4Q26; the stock is currently trading at 16.8x forward P/E, and the target price still implies about 7% downside.

  Comparison

  Compared with UMC and Vanguard, Novatek's drivers come more from SoC and AI edge applications rather than mature-node foundry price hikes.

  Risks

  Risks include the pace of OLED smartphone shipments, TDDI ASP and margin erosion or share loss, entry by Chinese competitors, and the pace of progress in fingerprint sensor products.

• TSMC / 2330.TT / TSM.US

  source of mature-node spillover demand and industry reference company

  Strengths

  TSMC is still rated Outperform by the report, with a target price of NT$2,780; the report notes that it is expanding mature-node capacity in Japan and Europe, while strong CoWoS demand is driving interposer demand.

  Weaknesses

  The report portrays TSMC mature-node demand as weak, citing the company's view that mature-node demand is not strong.

  Comparison

  Part of the bullish narrative for UMC and Vanguard depends on TSMC exiting older capacity, but the report estimates the scale of spillover is limited.

  Risks

  If TSMC changes its mature-node capacity expansion, customer migration, or interposer outsourcing pace, this could affect demand expectations for UMC and Vanguard.

Key data

• UMC share price performance since the start of the yearabout +150%The rise was mainly driven by expectations for mature-node price hikes and spillover demand from TSMC.
• Vanguard share price performance since the start of the yearabout +65%The logic behind the rise is similar to UMC, but the report believes Vanguard's fundamentals are relatively better.
• Potential spillover capacity share from TSMC Fab 2 and Fab 58–13% of UMC and Vanguard's combined 6-inch and 8-inch capacity; 4–6% of total capacityThe report believes this scale is insufficient to constitute meaningful spillover demand.
• UMC target priceNT$88.00；UMC.US US$13.6Raised from NT$47.00, but Underperform maintained.
• UMC valuation method2.5x target P/B × Q5-Q8 BVPS NT$35.2Target P/B raised from 1.5x to 2.5x.
• UMC potential returnabout 31% potential downside; dividend yield about 2%Based on the July 24 closing price.
• UMC revenue forecast+16% in 2026; +15% in 2027Driven by higher ASP and utilization.
• UMC ROE forecastrising from 14% to 18% from 2026 to 2028Still below the 28% ROE level during COVID.
• Vanguard target priceNT$146.00Raised from NT$94.00, Market-Perform maintained.
• Vanguard potential returnabout 7% potential downside; dividend yield about 3%Based on the July 24 closing price.
• Vanguard power management product revenue sharemore than 75%The report believes this makes Vanguard relatively better positioned against a backdrop of weak mature-node demand.
• VSMC phase-one capacity44KWPMCut from 55KWPM, with current demand already locked in by long-term agreements; mass production planned for 1Q27.
• Novatek target priceNT$480.00Raised from NT$370.00, Market-Perform maintained.
• Novatek potential returnabout 7% potential downside; dividend yield about 4%Based on the report's estimate.
• Novatek revenue forecast+9.7% in 2026; about +5% in 2027 and 2028The SoC business is driven by edge AI video-related applications.

Impact & implications

In investment terms, the report believes UMC's current share price has fully, and perhaps excessively, priced in mature-node price hikes and spillover demand, with valuation risk outweighing fundamental improvement; although Vanguard also faces short-term downside risk, it is relatively better than UMC due to stronger visibility in power management and VSMC demand; Novatek's SoC growth and cost pass-through provide some support, but high memory costs may suppress end demand. Overall, the report remains cautious on the share-price rerating of the mature-node foundry sector, emphasizing valuation, the authenticity of demand, and long-term competitive pressures.

Risks

• UMC valuation is elevated; if mature-node price hikes fall short of market expectations, the stock may pull back.
• Spillover demand from TSMC's exit of older capacity may be insufficient to support the rally narrative for UMC and Vanguard.
• High memory costs may weaken end demand and affect orders related to mature nodes, DDIC, and SoC.
• Competitive pressure from China's mature-node capacity may cause a long-term decline in 8-inch mature-node pricing.
• Potential UMC-Intel 3nm cooperation faces technological, customer-base, and capex hurdles, making it difficult to translate into financial returns.
• Vanguard faces risks from VSMC depreciation, integration and cost reduction, FX, and changes in China policy.
• Novatek faces risks from TDDI price and margin erosion, OLED smartphone shipment volatility, and entry by Chinese competitors.
• A contraction in overall market valuation multiples and geopolitical uncertainty may affect sector performance.

What to watch

• Whether UMC's actual 2H26 mature-node price increases exceed the high-single-digit range.
• Whether UMC's 2026–2028 ASP, utilization, depreciation, and ROE can meet the report's raised assumptions.
• Whether demand from TSMC Fab 2 and Fab 5 truly spills over to UMC and Vanguard, and whether the scale exceeds the report's estimates.
• The progress of TSMC's mature-node capacity expansion in Japan and Europe.
• Customer progress, capex plans, and revenue contribution timing for UMC's silicon photonics business.
• The actual feasibility of UMC's 3nm cooperation with Intel, capex sharing, and customer onboarding.
• VSMC 40nm mass-production progress, utilization of phase-one 44KWPM capacity, phase-two evaluation, and TSMC interposer outsourcing orders.
• Vanguard power management IC demand and the pricing trend for 8-inch mature-node capacity.
• Growth in Novatek's SoC revenue related to edge AI video, AI surveillance, and machine vision.
• Whether high memory costs cause order cuts or end-demand destruction in 4Q26.