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SUMCOSTU:S3X -9.26%66 Market Cap is €9,631 Mil as of Jul. 16, 2026. GuruFocus rates STU:S3X with a GF Score™ of 66/100 and a GF Value™ of €9.62 (Significantly Overvalued). The stock has 8 warning signs investors should review. Among 1,033 Semiconductors companies, SUMCO ranks better than 89.55% on this metric.
Market cap is the total market value to buy the whole company. It is equal to the share price times the number of Shares Outstanding (EOP). SUMCO's share price for the quarter that ended in Dec. 2025 was €7.742. SUMCO's Shares Outstanding (EOP) for the quarter that ended in Dec. 2025 was 350 Mil. Therefore, SUMCO's market cap for the quarter that ended in Dec. 2025 was €2,707 Mil.
SUMCO's quarterly market cap
increased
from Jun. 2025 (€2,308 Mil) to Sep. 2025 (€3,147 Mil) but then
declined
from Sep. 2025 (€3,147 Mil) to Dec. 2025 (€2,707 Mil).
SUMCO's annual market cap
declined
from Dec. 2023 (€4,787 Mil) to Dec. 2024 (€2,490 Mil) but then
increased
from Dec. 2024 (€2,490 Mil) to Dec. 2025 (€2,707 Mil).
Enterprise Value is the theoretical takeover price. It is more comprehensive than market capitalization (market cap), which only includes common equity. Enterprise Value is calculated as the market cap plus debt and minority interest and preferred shares, minus total cash and cash equivalents. SUMCO's Enterprise Value for Today is €11,449 Mil.
SUMCO (STU:S3X) Market Cap Explanation
Market cap is not the real price you pay for a company. If you buy the company and become its owner, you become the owner of the cash the company has, and you also assume the companys debt. The real price you pay is the Enterprise Value.
Warren Buffett uses the ratio of total market cap of all public traded companies over GDP to measure if the market is expensive. As of April 2012, the US total market cap is about $14.7 trillion, while the US GDP is about $15 trillion. The market was modestly overvalued.
SUMCO Market Cap Related Terms
SUMCO Market Cap Historical Data
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The historical data trend for SUMCO's Market Cap can be seen below:
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
STU:S3X vs AMAT, LRCX, KLAC: Market Cap Comparison
For the Semiconductor Equipment & Materials subindustry, SUMCO's Market Cap, along with its competitors' market caps and Market Cap data, can be viewed below:
* Competitive companies are chosen from companies within the same industry, with headquarter located in same country, with closest market capitalization; x-axis shows the market cap, and y-axis shows the term value; the bigger the dot, the larger the market cap. Note that "N/A" values will not show up in the chart.
SUMCO Market Cap vs Semiconductors Industry
For the Semiconductors industry and Technology sector, SUMCO's Market Cap distribution charts can be found below:
* The bar in red indicates where SUMCO's Market Cap falls into.
Market cap is the short version of market capitalization. It is the total market value to buy the whole company. It is equal to the share price times the number of shares outstanding.
SUMCO's Market Cap for the fiscal year that ended in Dec. 2025 is calculated as
* For Operating Data section: All numbers are indicated by the unit behind each term and all currency related amount are in USD. * For other sections: All numbers are in millions except for per share data, ratio, and percentage. All currency related amount are indicated in the company's associated stock exchange currency.
SUMCO (STU:S3X) has a Market Cap of €9,631 Mil as of Jul. 16, 2026. Market cap equals the total value of a company's shares: price times shares outstanding. View historical data on SUMCO and its competitors. According to the industry distribution chart, SUMCO ranks #108 out of 1033 companies in the Semiconductors industry, placing it in the top 10.5%.
Is SUMCO's Market Cap too high?
SUMCO's current Market Cap is €9,631 Mil. Based on the distribution chart, SUMCO ranks #108 out of 1033 companies in the Semiconductors industry, which is in the top quartile — a strong position relative to peers. Overall, SUMCO has a GF Score™ of 66/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does SUMCO's Market Cap compare to AMAT and LRCX?
According to the Semiconductors industry distribution chart, SUMCO ranks #108 out of 1033 companies for Market Cap. This places SUMCO in the top 11% of its industry — outperforming the majority of peers. The industry median Market Cap is 517.36. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Market Cap for a Semiconductors company?
The median Market Cap among Semiconductors companies is 517.36, based on 1,033 companies in the industry. Companies in the top quartile (top 25%) have a Market Cap significantly above this median, while those in the bottom quartile fall well below. However, Market Cap should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Market Cap mean?
A high Market Cap can signal that a stock is expensive relative to its fundamentals. Market cap equals the total value of a company's shares: price times shares outstanding. View historical data on SUMCO and its competitors. For the Semiconductors industry, the median Market Cap is 517.36 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. SUMCO's current Market Cap is €9,631 Mil. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is SUMCO stock overvalued right now?
Based on GuruFocus' analysis, SUMCO (STU:S3X) is currently considered Significantly Overvalued. The stock's GF Value™ is €9.62, compared to a current price of €26.95 — trading 180.1% above its estimated fair value. The current Market Cap is €9,631 Mil. SUMCO's overall GF Score™ is 66/100 with 8 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Market Cap calculated?
Market Cap is calculated from a company's financial statements. For SUMCO (STU:S3X), the current Market Cap is €9,631 Mil as of Jul. 16, 2026. GuruFocus calculates this using data sourced from SEC filings and annual reports. See the calculation section and 30-year financial data on this page for the full breakdown.
Is SUMCO (STU:S3X) Overvalued in 2026?
Based on GuruFocus' analysis, SUMCO stock appears to be overvalued.
The current stock price of €26.95 is trading 180.1% above its estimated GF Value™ of €9.62.
GuruFocus considers SUMCO to be Significantly Overvalued.
Key valuation signals for STU:S3X:
Market Cap: €9,631 Mil
GF Value™: €9.62 vs. price of €26.95 (180.1% above fair value)
No single metric tells the full story. See the STU:S3X stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Founded in 1999 as a joint venture between Nippon Steel and two Mitsubishi entities, Sumco is the world's second-largest semiconductor-grade silicon wafer manufacturer, with an estimated 21% market share in 2025. Sumco is headquartered in Tokyo and operates seven production sites across Japan. It also maintains sales and support offices in Taiwan, the US, the UK, Indonesia, and Singapore. Sumco sells to most semiconductor manufacturers like TSMC, Intel, Samsung, and Micron. The firm employs over 9,700 people.
66GF Score
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