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Formosa Optical Technology CoROCO:5312 +0.67%82 ROC (Joel Greenblatt) % is 17.94% as of Mar. 2026, which is 33% below its 10-year median of 26.93. GuruFocus rates ROCO:5312 with a GF Score™ of 82/100 and a GF Value™ of NT$110.74 (Modestly Undervalued). The stock has 3 warning signs investors should review. Among 838 Medical Devices & Instruments companies, Formosa Optical Technology Co ranks better than 68.14% on this metric.
Joel Greenblatt defined Return on Capital differently in his book The Little Book That Still Beats the Market (Little Books. Big Profits). He defines ROC (Joel Greenblatt) % as EBIT divided by the total of Property, Plant and Equipment and net working capital. Formosa Optical Technology Co's annualized ROC (Joel Greenblatt) % for the quarter that ended in Mar. 2026 was 17.94%.
The historical rank and industry rank for Formosa Optical Technology Co's ROC (Joel Greenblatt) % or its related term are showing as below:
ROCO:5312'
s ROC (Joel Greenblatt) % Range Over the Past 10 Years
Min: 11.73 Med: 26.93 Max: 37.5
Current: 18.8
During the past 13 years, Formosa Optical Technology Co's highest ROC (Joel Greenblatt) % was 37.50%. The lowest was 11.73%. And the median was 26.93%.
ROCO:5312's ROC (Joel Greenblatt) % is ranked better than 68.14% of 838
companies
in the Medical Devices & Instruments industry
Industry Median: 4.64
vs ROCO:5312: 18.80
Formosa Optical Technology Co (ROCO:5312) ROC (Joel Greenblatt) % Explanation
The way Joel Greenblatt defines Return on Capital is a more accurate measure of how efficiently the company generates returns onthe capital actually invested in the business. EBIT is used instead of net income because the tax and interest payment may be affected by factors other than the core business operation. Intangible assets are not included in the calculation because they don't need to be replaced.
* 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.
Formosa Optical Technology Co ROC (Joel Greenblatt) % Chart
ROCO:5312 vs ISRG, BDX, MDLN: ROC (Joel Greenblatt) % Comparison
For the Medical Instruments & Supplies subindustry, Formosa Optical Technology Co's ROC (Joel Greenblatt) %, along with its competitors' market caps and ROC (Joel Greenblatt) % 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.
Formosa Optical Technology Co ROC (Joel Greenblatt) % vs Medical Devices & Instruments Industry
For the Medical Devices & Instruments industry and Healthcare sector, Formosa Optical Technology Co's ROC (Joel Greenblatt) % distribution charts can be found below:
* The bar in red indicates where Formosa Optical Technology Co's ROC (Joel Greenblatt) % falls into.
Formosa Optical Technology Co ROC (Joel Greenblatt) % Calculation
Joel Greenblatt defined Return on Capital differently in his book The Little Book That Still Beats the Market (Little Books. Big Profits) . He defines Return on Capital as follows:
EBIT stands for Earnings Before Interest and Taxes.
Fixed Assets are also known as non-current assets. They include the Property, Plant and Equipment that the firm needs in its operation.
GuruFocus calculates net working capital as: (Accounts Receivable + Total Inventories + Other Current Assets) - (Accounts Payable & Accrued Expense + Deferred Revenue + Other Current Liabilities). We're trying to account for OPERATING assets and liabilities (part of daily business) when calculating working capital. Cash and marketable securities are considered NON-OPERATING assets and are not included in calculation. We will also back out all interest bearing debt, short term debt and the portion of long term debt that is due in the current period from the current liabilities. This debt will be considered when computing cost of capital and it would be inappropriate to count it twice.
Note:
The EBIT data used here is four times the quarterly (Mar. 2026) EBIT 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.
What does a ROC (Joel Greenblatt) % of 17.94% mean?
Formosa Optical Technology Co (ROCO:5312) has a ROC (Joel Greenblatt) % of 17.94% as of Mar. 2026. Joel Greenblatt's return on capital is the ratio of EBIT to average fixed assets and net working capital. View historical data on Formosa Optical Technology Co and its competitors. This is 33% below median its historical median of 26.93. Over the past decade, Formosa Optical Technology Co's ROC (Joel Greenblatt) % has ranged from 11.73 to 37.50. According to the industry distribution chart, Formosa Optical Technology Co ranks #267 out of 838 companies in the Medical Devices & Instruments industry, placing it in the top 31.9%.
Is Formosa Optical Technology Co's ROC (Joel Greenblatt) % too high?
Formosa Optical Technology Co's current ROC (Joel Greenblatt) % of 17.94% is 33% below median its 10-year median of 26.93. Over the past 10 years, this metric has ranged from a low of 11.73 to a high of 37.50. The Medical Devices & Instruments industry median ROC (Joel Greenblatt) % is 4.64. Formosa Optical Technology Co's value of 17.94% is 286.6% above this industry median. Based on the distribution chart, Formosa Optical Technology Co ranks #267 out of 838 companies in the Medical Devices & Instruments industry, which is above the industry midpoint. Overall, Formosa Optical Technology Co has a GF Score™ of 82/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Formosa Optical Technology Co's ROC (Joel Greenblatt) % compare to ISRG and BDX?
According to the Medical Devices & Instruments industry distribution chart, Formosa Optical Technology Co ranks #267 out of 838 companies for ROC (Joel Greenblatt) %. This puts Formosa Optical Technology Co in the upper half of its industry. The industry median ROC (Joel Greenblatt) % is 4.64. Formosa Optical Technology Co's value of 17.94% is 286.6% above this benchmark. Historically, Formosa Optical Technology Co's own ROC (Joel Greenblatt) % has ranged from 11.73 to 37.50 over the past decade. While the company's 10-year median is 26.93 vs. the industry median of 4.64, Formosa Optical Technology 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 ROC (Joel Greenblatt) % for a Medical Devices & Instruments company?
The median ROC (Joel Greenblatt) % among Medical Devices & Instruments companies is 4.64, based on 838 companies in the industry. Companies in the top quartile (top 25%) have a ROC (Joel Greenblatt) % significantly above this median, while those in the bottom quartile fall well below. However, ROC (Joel Greenblatt) % should not be evaluated in isolation — investors should consider it alongside profitability, growth, and financial strength metrics. Formosa Optical Technology Co's current ROC (Joel Greenblatt) % of 17.94% is 286.6% 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 ROC (Joel Greenblatt) % mean?
A high ROC (Joel Greenblatt) % can signal that a stock is expensive relative to its fundamentals. Joel Greenblatt's return on capital is the ratio of EBIT to average fixed assets and net working capital. View historical data on Formosa Optical Technology Co and its competitors. For the Medical Devices & Instruments industry, the median ROC (Joel Greenblatt) % is 4.64 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Formosa Optical Technology Co's current ROC (Joel Greenblatt) % is 17.94%, which is 33% below median its own 10-year median of 26.93. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Formosa Optical Technology Co stock overvalued right now?
Based on GuruFocus' analysis, Formosa Optical Technology Co (ROCO:5312) is currently considered Modestly Undervalued. The stock's GF Value™ is NT$110.74, compared to a current price of NT$89.50 — trading 19.2% below its estimated fair value. The current ROC (Joel Greenblatt) % is 17.94%, which is 33% below median its 10-year median of 26.93 and 286.6% above the Medical Devices & Instruments industry median of 4.64. Formosa Optical Technology Co's overall GF Score™ is 82/100 with 3 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is ROC (Joel Greenblatt) % calculated?
ROC (Joel Greenblatt) % is calculated from a company's financial statements. For Formosa Optical Technology Co (ROCO:5312), the current ROC (Joel Greenblatt) % is 17.94% as of Mar. 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 Formosa Optical Technology Co (ROCO:5312) Overvalued in 2026?
Based on GuruFocus' analysis, Formosa Optical Technology Co stock appears to be undervalued.
The current stock price of NT$89.50 is trading 19.2% below its estimated GF Value™ of NT$110.74.
GuruFocus considers Formosa Optical Technology Co to be Modestly Undervalued.
Key valuation signals for ROCO:5312:
ROC (Joel Greenblatt) %: 17.94% (33% below median its 10-year median of 26.93)
GF Value™: NT$110.74 vs. price of NT$89.50 (19.2% below fair value)
Industry Position: 286.6% above the Medical Devices & Instruments median (#267 of 838)
No single metric tells the full story. See the ROCO:5312 stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Formosa Optical Technology Co Ltd is mainly engaged in the eyewear business, including optometry services and the retail business selling contact lenses and eye drops. The Group mainly derives revenue from the business divisions of Formosa Optical Technology and Bo Wei Optical, with Formosa Optical Technology generating maximum revenue. The majority of revenue is derived from the sale of glasses. The Group generates the majority of its revenue from Taiwan.
82GF Score
Get the complete analysis for ROCO:5312
ROC (Joel Greenblatt) % is just one metric. See GF Value™, 30-year financials, guru trades, warning signs, and more.
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