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Keystone MicrotechROCO:6683 -8.16%79 Operating Margin % is 24.83% as of Dec. 2025, which is 17% below its 10-year median of 29.83. GuruFocus rates ROCO:6683 with a GF Score™ of 79/100 and a GF Value™ of NT$486.03 (Significantly Overvalued). The stock has 2 warning signs investors should review. Among 1,023 Semiconductors companies, Keystone Microtech ranks better than 89.15% on this metric.
Just like Gross Margin %, it is important to see a company maintains its operating margin over time. Among the same industry, a company with higher operating margin is more efficient in its operation. It is also more stable during industry slowdown or recessions. Peter Lynch prefers those with higher margins than those with lower margins.
Be Aware
Operating Margin % can be manipulated by adjusting the rate of depreciation, depletion and amortization (DDA).
If a company is facing competition, its Operating Margin % may decline. Often the Operating Margin % declines well before the company's Revenue or even profit decline. Therefore, Operating Margin % is a very important indicator of whether the company is facing problems.
For instance, by 2012, Nokia (NOK)'s problems were well known and its stock had lost more than 90% of its market value since 2007. But Nokias Operating Margin % had already been in decline since 2002, although its Earnings per Share (Diluted) were still rising. Investors who paid attention to Operating Margin % would have avoided this huge loss. The same can be said for Research-in-Motion (RIMM).
Therefore, Operating Margin % is a very important screening filter for GuruFocus. GuruFocus's Buffett-Munger screener requires that the profit margin is either consistent or expanding. The Model Portfolio of the Buffett-Munger screener has outperformed the market every year since inception in 2009.
Keystone Microtech Operating Margin % Related Terms
Keystone Microtech Operating Margin % Historical Data
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The historical data trend for Keystone Microtech's Operating Margin % 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.
ROCO:6683 vs AMAT, LRCX, KLAC: Operating Margin % Comparison
For the Semiconductor Equipment & Materials subindustry, Keystone Microtech's Operating Margin %, along with its competitors' market caps and Operating Margin % 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.
Keystone Microtech Operating Margin % vs Semiconductors Industry
For the Semiconductors industry and Technology sector, Keystone Microtech's Operating Margin % distribution charts can be found below:
* The bar in red indicates where Keystone Microtech's Operating Margin % falls into.
Operating Margin % - also known as operating income margin, operating profit margin and return on sales (ROS) - is the ratio of Operating Income divided by net sales or Revenue, usually presented in percent.
Keystone Microtech's Operating Margin % 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.
Keystone Microtech (ROCO:6683) has a Operating Margin % of 24.83% as of Dec. 2025. Operating margin is the ratio of total operating income to net sales. View historical data on Keystone Microtech and its competitors. This is 17% below median its historical median of 29.83. Over the past decade, Keystone Microtech's Operating Margin % has ranged from 24.90 to 36.12. According to the industry distribution chart, Keystone Microtech ranks #111 out of 1023 companies in the Semiconductors industry, placing it in the top 10.9%.
Is Keystone Microtech's Operating Margin % too high?
Keystone Microtech's current Operating Margin % of 24.83% is 17% below median its 10-year median of 29.83. Over the past 10 years, this metric has ranged from a low of 24.90 to a high of 36.12. The Semiconductors industry median Operating Margin % is 5.33. Keystone Microtech's value of 24.83% is 365.9% above this industry median. Based on the distribution chart, Keystone Microtech ranks #111 out of 1023 companies in the Semiconductors industry, which is in the top quartile — a strong position relative to peers. Overall, Keystone Microtech has a GF Score™ of 79/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Keystone Microtech's Operating Margin % compare to AMAT and LRCX?
According to the Semiconductors industry distribution chart, Keystone Microtech ranks #111 out of 1023 companies for Operating Margin %. This places Keystone Microtech in the top 11% of its industry — outperforming the majority of peers. The industry median Operating Margin % is 5.33. Keystone Microtech's value of 24.83% is 365.9% above this benchmark. Historically, Keystone Microtech's own Operating Margin % has ranged from 24.90 to 36.12 over the past decade. While the company's 10-year median is 29.83 vs. the industry median of 5.33, Keystone Microtech has consistently been above the industry average. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Operating Margin % for a Semiconductors company?
The median Operating Margin % among Semiconductors companies is 5.33, based on 1,023 companies in the industry. Companies in the top quartile (top 25%) have a Operating Margin % significantly above this median, while those in the bottom quartile fall well below. However, Operating Margin % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Keystone Microtech's current Operating Margin % of 24.83% is 365.9% above the industry median. Use the industry distribution chart on this page to see where any company falls relative to its peers.
What does a high Operating Margin % mean?
A high Operating Margin % can signal that a stock is expensive relative to its fundamentals. Operating margin is the ratio of total operating income to net sales. View historical data on Keystone Microtech and its competitors. For the Semiconductors industry, the median Operating Margin % is 5.33 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Keystone Microtech's current Operating Margin % is 24.83%, which is 17% below median its own 10-year median of 29.83. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Keystone Microtech stock overvalued right now?
Based on GuruFocus' analysis, Keystone Microtech (ROCO:6683) is currently considered Significantly Overvalued. The stock's GF Value™ is NT$486.03, compared to a current price of NT$1,350.00 — trading 177.8% above its estimated fair value. The current Operating Margin % is 24.83%, which is 17% below median its 10-year median of 29.83 and 365.9% above the Semiconductors industry median of 5.33. Keystone Microtech's overall GF Score™ is 79/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Operating Margin % calculated?
Operating Margin % is calculated from a company's financial statements. For Keystone Microtech (ROCO:6683), the current Operating Margin % is 24.83% as of Dec. 2025. 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 Keystone Microtech (ROCO:6683) Overvalued in 2026?
Based on GuruFocus' analysis, Keystone Microtech stock appears to be overvalued.
The current stock price of NT$1,350.00 is trading 177.8% above its estimated GF Value™ of NT$486.03.
GuruFocus considers Keystone Microtech to be Significantly Overvalued.
Key valuation signals for ROCO:6683:
Operating Margin %: 24.83% (17% below median its 10-year median of 29.83)
GF Value™: NT$486.03 vs. price of NT$1,350.00 (177.8% above fair value)
Industry Position: 365.9% above the Semiconductors median (#111 of 1023)
No single metric tells the full story. See the ROCO:6683 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Keystone Microtech Corp operates as a semiconductor device manufacturing company. The company is mainly an important operating department engaged in the manufacture and sale of various circuit testing solutions for semiconductors, including IC front-end test solutions (probe cards and substrates), IC back-end test solutions (load boards and burn-in boards), and other related testing boards. Geographically, it operates in Taiwan and other regions, out of which the majority of its revenue is derived from Taiwan.
79GF Score
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