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Keystone MicrotechROCO:6683 -3.61%85 Piotroski F-Score is 7 as of Aug. 31, 2026, which is 40% above its 10-year median of 5.00. GuruFocus rates ROCO:6683 with a GF Score™ of 85/100 and a GF Value™ of NT$537.54 (Significantly Overvalued). The stock has 2 warning signs investors should review. Among 997 Semiconductors companies, Keystone Microtech ranks better than 92.18% on this metric.
Good Sign:
Piotroski F-Score is 7, indicates a very healthy situation.
The zones of discrimination were as such:
Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Keystone Microtech has an F-score of 7. It is a good or high score, which usually indicates a very healthy situation.
The historical rank and industry rank for Keystone Microtech's Piotroski F-Score or its related term are showing as below:
ROCO:6683'
s Piotroski F-Score Range Over the Past 10 Years
Min: 3 Med: 5 Max: 8
Current: 7
During the past 12 years, the highest Piotroski F-Score of Keystone Microtech was 8. The lowest was 3. And the median was 5.
The developer of the system is Joseph D. Piotroski is relatively unknown accounting professor who shuns publicity and rarely gives interviews.
He graduated from the University of Illinois with a B.S. in accounting in 1989, received an M.B.A. from Indiana University in 1994. Five years later, in 1999, after earning a Ph.D. in accounting from the University of Michigan, he became an associate professor of accounting at the University of Chicago.
He wanted to see if he can develop a system (using a simple nine-point scoring system) that can increase the returns of a strategy of investing in low price to book (referred to in the paper as high book to market) value companies.
What he found was something that exceeded his most optimistic expectations.
Buying only those companies that scored highest (8 or 9) on his nine-point scale, or F-Score as he called it, over the 20 year period from 1976 to 1996 led to an average out-performance over the market of 13.4%.
Even more impressive were the results of a strategy of investing in the highest F-Score companies (8 or 9) and shorting companies with the lowest F-Score (0 or 1).
Over the same period from 1976 to 1996 (20 years) this strategy led to an average yearly return of 23%, substantially outperforming the average S&P 500 index return of 15.83% over the same period.
Keystone Microtech Piotroski F-Score Related Terms
Keystone Microtech Piotroski F-Score Historical Data
* Premium members only.
The historical data trend for Keystone Microtech's Piotroski F-Score 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 LRCX, AMAT, KLAC: Piotroski F-Score Comparison
For the Semiconductor Equipment & Materials subindustry, Keystone Microtech's Piotroski F-Score, along with its competitors' market caps and Piotroski F-Score 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 Piotroski F-Score vs Semiconductors Industry
For the Semiconductors industry and Technology sector, Keystone Microtech's Piotroski F-Score distribution charts can be found below:
* The bar in red indicates where Keystone Microtech's Piotroski F-Score falls into.
* 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.
This Year (Jun26) TTM:
Last Year (Jun25) TTM:
Net Income was 138.891 + 145.159 + 169.497 + 163.788 = NT$617 Mil. Cash Flow from Operations was 303.766 + 228.95 + 249.231 + -80.696 = NT$701 Mil. Revenue was 555.647 + 579.999 + 664.648 + 651.597 = NT$2,452 Mil. Gross Profit was 251.75 + 287.094 + 324.343 + 331.253 = NT$1,194 Mil.
Average Total Assets from the begining of this year (Jun25)
to the end of this year (Jun26) was
(3215.967 + 3109.382 + 3367.579 + 3595.685 + 3773.939) / 5 = NT$3412.5104 Mil. Total Assets at the begining of this year (Jun25) was NT$3,216 Mil. Long-Term Debt & Capital Lease Obligation was NT$4 Mil. Total Current Assets was NT$2,813 Mil. Total Current Liabilities was NT$915 Mil.
Net Income was 108.413 + 145.379 + 102.096 + 32.901 = NT$389 Mil.
*Note: If the latest quarterly/semi-annual/annual total assets data is 0, then we will use previous quarterly/semi-annual/annual data for all the items in the balance sheet.
Profitability
Question 1. Return on Assets (ROA)
Net income before extraordinary items for the year divided by Total Assets at the beginning of the year.
Score 1 if positive, 0 if negative.
Keystone Microtech's current Net Income (TTM) was 617.
==> Positive ==> Score 1.
Question 2. Cash Flow Return on Assets (CFROA)
Net cash flow from operating activities (operating cash flow) divided by Total Assets at the beginning of the year.
Keystone Microtech's return on assets of this year was 0.19195937. Keystone Microtech's return on assets of last year was 0.13734458.
==> This year is higher. ==> Score 1.
Question 4. Quality of Earnings (Accrual)
Compare Cash flow return on assets (2) to return on assets (1)
Keystone Microtech's gearing of this year was 0.00125304. Keystone Microtech's gearing of last year was 0.00167524.
==> This year is lower or equal to last year. ==> Score 1.
Question 6. Change in Working Capital (Liquidity)
Compare this year's current ratio (current assets divided by current liabilities) to last year's current ratio.
Score 1 if this year's current ratio is higher, 0 if it's lower
Keystone Microtech's current ratio of this year was 3.0750135. Keystone Microtech's current ratio of last year was 2.82815194.
==> This year's current ratio is higher. ==> Score 1.
Question 7. Change in Shares in Issue
Compare the number of shares in issue this year, to the number in issue last year.
Score 0 if there is larger number of shares in issue this year, 1 otherwise.
Keystone Microtech's number of shares in issue this year was 27.527. Keystone Microtech's number of shares in issue last year was 27.418.
==> There is larger number of shares in issue this year. ==> Score 0.
Efficiency
Question 8. Change in Gross Margin
Compare this year's gross margin (Gross Profit divided by sales) to last year's.
Score 1 if this year's gross margin is higher, 0 if it's lower.
Keystone Microtech's gross margin of this year was 0.48715053. Keystone Microtech's gross margin of last year was 0.50571042.
==> Last year's gross margin is higher ==> Score 0.
Question 9. Change in asset turnover
Compare this year's asset turnover (total sales for the year divided by total assets at the beginning of the year) to last year's asset turnover ratio.
Score 1 if this year's asset turnover ratio is higher, 0 if it's lower
Keystone Microtech's asset turnover of this year was 0.76241174. Keystone Microtech's asset turnover of last year was 0.69363696.
==> This year's asset turnover is higher. ==> Score 1.
Evaluation
Piotroski F-Score
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7
Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Keystone Microtech has an F-score of 7. It is a good or high score, which usually indicates a very healthy situation.
Keystone Microtech (ROCO:6683) has a Piotroski F-Score of 7 as of Aug. 31, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Keystone Microtech and its competitors. This is 40% above median its historical median of 5.00. Over the past decade, Keystone Microtech's Piotroski F-Score has ranged from 3.00 to 8.00. According to the industry distribution chart, Keystone Microtech ranks #78 out of 997 companies in the Semiconductors industry, placing it in the top 7.8%.
Is Keystone Microtech's Piotroski F-Score too high?
Keystone Microtech's current Piotroski F-Score of 7 is 40% above median its 10-year median of 5.00. Over the past 10 years, this metric has ranged from a low of 3.00 to a high of 8.00. The Semiconductors industry median Piotroski F-Score is 5.00. Keystone Microtech's value of 7 is 40% above this industry median. Based on the distribution chart, Keystone Microtech ranks #78 out of 997 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 85/100 and is considered Significantly Overvalued, reflecting its overall financial health beyond just this single metric.
How does Keystone Microtech's Piotroski F-Score compare to LRCX and AMAT?
According to the Semiconductors industry distribution chart, Keystone Microtech ranks #78 out of 997 companies for Piotroski F-Score. This places Keystone Microtech in the top 8% of its industry — outperforming the majority of peers. The industry median Piotroski F-Score is 5.00. Keystone Microtech's value of 7 is 40% above this benchmark. Historically, Keystone Microtech's own Piotroski F-Score has ranged from 3.00 to 8.00 over the past decade. While the company's 10-year median is 5.00 vs. the industry median of 5.00, 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 Piotroski F-Score for a Semiconductors company?
The median Piotroski F-Score among Semiconductors companies is 5.00, based on 997 companies in the industry. Companies in the top quartile (top 25%) have a Piotroski F-Score significantly above this median, while those in the bottom quartile fall well below. However, Piotroski F-Score should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Keystone Microtech's current Piotroski F-Score of 7 is 40% 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 Piotroski F-Score mean?
A high Piotroski F-Score can signal that a stock is expensive relative to its fundamentals. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Keystone Microtech and its competitors. For the Semiconductors industry, the median Piotroski F-Score is 5.00 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Keystone Microtech's current Piotroski F-Score is 7, which is 40% above median its own 10-year median of 5.00. 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$537.54, compared to a current price of NT$1,200.00 — trading 123.2% above its estimated fair value. The current Piotroski F-Score is 7, which is 40% above median its 10-year median of 5.00 and 40% above the Semiconductors industry median of 5.00. Keystone Microtech's overall GF Score™ is 85/100 with 2 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Piotroski F-Score calculated?
Piotroski F-Score is calculated from a company's financial statements. For Keystone Microtech (ROCO:6683), the current Piotroski F-Score is 7 as of Aug. 31, 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 Keystone Microtech (ROCO:6683) Overvalued in 2026?
Based on GuruFocus' analysis, Keystone Microtech stock appears to be overvalued.
The current stock price of NT$1,200.00 is trading 123.2% above its estimated GF Value™ of NT$537.54.
GuruFocus considers Keystone Microtech to be Significantly Overvalued.
Key valuation signals for ROCO:6683:
Piotroski F-Score: 7 (40% above median its 10-year median of 5.00)
GF Value™: NT$537.54 vs. price of NT$1,200.00 (123.2% above fair value)
Industry Position: 40% above the Semiconductors median (#78 of 997)
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.
85GF Score
Get the complete analysis for ROCO:6683
Piotroski F-Score is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
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