Focused on building reliable datasets, financial models, and research tools for value-minded investors. Committed to turning complex data into practical guidance for value-investing and long-term wealth.
Dr. Charlie Tian is the founder and CEO of GuruFocus.com, a leading global investment research platform established in 2004. With a Ph.D. in physics, Dr. Tian transitioned from science to finance, applying a data-driven, disciplined approach to value investing.
STU:SXC'
s Piotroski F-Score Range Over the Past 10 Years
Min: 4 Med: 7 Max: 9
Current: 7
During the past 13 years, the highest Piotroski F-Score of Sunny Optical Technology (Group) Co was 9. The lowest was 4. And the median was 7.
Sunny Optical Technology (Group) Co (STU:SXC) Piotroski F-Score Explanation
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.
Sunny Optical Technology (Group) Co Piotroski F-Score Related Terms
Sunny Optical Technology (Group) Co Piotroski F-Score Historical Data
* 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.
Sunny Optical Technology (Group) Co Piotroski F-Score Chart
For the Electronic Components subindustry, Sunny Optical Technology (Group) Co'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.
Sunny Optical Technology (Group) Co Piotroski F-Score vs Hardware Industry
For the Hardware industry and Technology sector, Sunny Optical Technology (Group) Co's Piotroski F-Score distribution charts can be found below:
* The bar in red indicates where Sunny Optical Technology (Group) Co'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.
*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.
Sunny Optical Technology (Group) Co's current Net Income (TTM) was 563.
==> 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.
Score 1 if positive, 0 if negative.
Sunny Optical Technology (Group) Co's current Cash Flow from Operations (TTM) was 737.
==> Positive ==> Score 1.
Question 3. Change in Return on Assets
Compare this year's return on assets (1) to last year's return on assets.
Sunny Optical Technology (Group) Co's return on assets of this year was 0.07969874. Sunny Optical Technology (Group) Co's return on assets of last year was 0.05480961.
==> This year is higher. ==> Score 1.
Question 4. Quality of Earnings (Accrual)
Compare Cash flow return on assets (2) to return on assets (1)
Sunny Optical Technology (Group) Co's gearing of this year was 0.02618973. Sunny Optical Technology (Group) Co's gearing of last year was 0.09872068.
==> 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
Sunny Optical Technology (Group) Co's current ratio of this year was 1.56643993. Sunny Optical Technology (Group) Co's current ratio of last year was 1.67295197.
==> Last year's current ratio is higher ==> Score 0.
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.
Sunny Optical Technology (Group) Co's number of shares in issue this year was 1092.083. Sunny Optical Technology (Group) Co's number of shares in issue last year was 1088.891.
==> 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.
Sunny Optical Technology (Group) Co's gross margin of this year was 0.19699424. Sunny Optical Technology (Group) Co's gross margin of last year was 0.1829514.
==> This year's gross margin is higher. ==> Score 1.
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
Sunny Optical Technology (Group) Co's asset turnover of this year was 0.74266545. Sunny Optical Technology (Group) Co's asset turnover of last year was 0.77761535.
==> Last year's asset turnover is higher ==> Score 0.
Evaluation
Piotroski F-Score
=
Que. 1
+
Que. 2
+
Que. 3
+
Que. 4
+
Que. 5
+
Que. 6
+
Que. 7
+
Que. 8
+
Que. 9
=
1
+
1
+
1
+
1
+
1
+
0
+
0
+
1
+
0
=
6
Good or high score = 7, 8, 9
Bad or low score = 0, 1, 2, 3
Sunny Optical Technology (Group) Co has an F-score of 6 indicating the company's financial situation is typical for a stable company.
Sunny Optical Technology (Group) Co (STU:SXC) has a Piotroski F-Score of 7 as of Jul. 15, 2026. The Piotroski F-score grades a company's business operating strength from 0-9. View historical data on Sunny Optical Technology (Group) Co and its competitors. This is near median its historical median of 7.00. Over the past decade, Sunny Optical Technology (Group) Co's Piotroski F-Score has ranged from 4.00 to 9.00. According to the industry distribution chart, Sunny Optical Technology (Group) Co ranks #215 out of 2434 companies in the Hardware industry, placing it in the top 8.8%.
Is Sunny Optical Technology (Group) Co's Piotroski F-Score too high?
Sunny Optical Technology (Group) Co's current Piotroski F-Score of 7 is near median its 10-year median of 7.00. Over the past 10 years, this metric has ranged from a low of 4.00 to a high of 9.00. The Hardware industry median Piotroski F-Score is 5.00. Sunny Optical Technology (Group) Co's value of 7 is 40% above this industry median. Based on the distribution chart, Sunny Optical Technology (Group) Co ranks #215 out of 2434 companies in the Hardware industry, which is in the top quartile — a strong position relative to peers. Overall, Sunny Optical Technology (Group) Co has a GF Score™ of 81/100 and is considered Significantly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Sunny Optical Technology (Group) Co's Piotroski F-Score compare to APH and GLW?
According to the Hardware industry distribution chart, Sunny Optical Technology (Group) Co ranks #215 out of 2434 companies for Piotroski F-Score. This places Sunny Optical Technology (Group) Co in the top 9% of its industry — outperforming the majority of peers. The industry median Piotroski F-Score is 5.00. Sunny Optical Technology (Group) Co's value of 7 is 40% above this benchmark. Historically, Sunny Optical Technology (Group) Co's own Piotroski F-Score has ranged from 4.00 to 9.00 over the past decade. While the company's 10-year median is 7.00 vs. the industry median of 5.00, Sunny Optical Technology (Group) Co 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 Hardware company?
The median Piotroski F-Score among Hardware companies is 5.00, based on 2,434 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. Sunny Optical Technology (Group) Co'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 Sunny Optical Technology (Group) Co and its competitors. For the Hardware 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. Sunny Optical Technology (Group) Co's current Piotroski F-Score is 7, which is near median its own 10-year median of 7.00. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Sunny Optical Technology (Group) Co stock overvalued right now?
Based on GuruFocus' analysis, Sunny Optical Technology (Group) Co (STU:SXC) is currently considered Significantly Undervalued. The stock's GF Value™ is €9.35, compared to a current price of €6.16 — trading 34.1% below its estimated fair value. The current Piotroski F-Score is 7, which is near median its 10-year median of 7.00 and 40% above the Hardware industry median of 5.00. Sunny Optical Technology (Group) Co's overall GF Score™ is 81/100 with 6 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 Sunny Optical Technology (Group) Co (STU:SXC), the current Piotroski F-Score is 7 as of Jul. 15, 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 Sunny Optical Technology (Group) Co (STU:SXC) Overvalued in 2026?
Based on GuruFocus' analysis, Sunny Optical Technology (Group) Co stock appears to be undervalued.
The current stock price of €6.16 is trading 34.1% below its estimated GF Value™ of €9.35.
GuruFocus considers Sunny Optical Technology (Group) Co to be Significantly Undervalued.
Key valuation signals for STU:SXC:
Piotroski F-Score: 7 (near median its 10-year median of 7.00)
GF Value™: €9.35 vs. price of €6.16 (34.1% below fair value)
Industry Position: 40% above the Hardware median (#215 of 2434)
No single metric tells the full story. See the STU:SXC stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Sunny Optical Technology (Group) Co Business Description
Headquartered in Yuyao, China, Sunny Optical is one of China's biggest handset camera module makers and the world's largest handset lens sets manufacturer. Higher-margin lens sets are used in smartphones, vehicles, and extended reality. Sunny Optical is a key beneficiary of the secular growth of extended-reality devices and vehicle camera demand, as advanced driver-assistance systems witness rising adoption among automakers. The firm also manufactures optical instruments, such as high-end microscopes and optical measuring instruments. The company employed over 34,393 people as of Dec. 31, 2025.
81GF Score
Get the complete analysis for STU:SXC
Piotroski F-Score is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
Quick Browse
Personalize
Premium Gurus 
Create New Portfolio
STU:SXC has been successfully added to your 
