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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. Inspire Medical Systems's annualized ROC (Joel Greenblatt) % for the quarter that ended in Mar. 2026 was -1.45%.
The historical rank and industry rank for Inspire Medical Systems's ROC (Joel Greenblatt) % or its related term are showing as below:
STU:2DR'
s ROC (Joel Greenblatt) % Range Over the Past 10 Years
Min: -1423.28 Med: -218.76 Max: 37.52
Current: 21.24
During the past 11 years, Inspire Medical Systems's highest ROC (Joel Greenblatt) % was 37.52%. The lowest was -1423.28%. And the median was -218.76%.
STU:2DR's ROC (Joel Greenblatt) % is ranked better than 71.55% of 840
companies
in the Medical Devices & Instruments industry
Industry Median: 4.145
vs STU:2DR: 21.24
Inspire Medical Systems's 5-Year average Growth Rate of ROC (Joel Greenblatt) % was 0.00% per year.
Inspire Medical Systems (STU:2DR) 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.
Inspire Medical Systems ROC (Joel Greenblatt) % Related Terms
Inspire Medical Systems ROC (Joel Greenblatt) % Historical Data
* Premium members only.
The historical data trend for Inspire Medical Systems's ROC (Joel Greenblatt) % 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.
Inspire Medical Systems ROC (Joel Greenblatt) % Chart
STU:2DR vs ENOV, PRCT, AHCO: ROC (Joel Greenblatt) % Comparison
For the Medical Devices subindustry, Inspire Medical Systems'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.
Inspire Medical Systems ROC (Joel Greenblatt) % vs Medical Devices & Instruments Industry
For the Medical Devices & Instruments industry and Healthcare sector, Inspire Medical Systems's ROC (Joel Greenblatt) % distribution charts can be found below:
* The bar in red indicates where Inspire Medical Systems's ROC (Joel Greenblatt) % falls into.
Inspire Medical Systems 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 -1.45% mean?
Inspire Medical Systems (STU:2DR) has a ROC (Joel Greenblatt) % of -1.45% 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 Inspire Medical Systems and its competitors. According to the industry distribution chart, Inspire Medical Systems ranks #239 out of 840 companies in the Medical Devices & Instruments industry, placing it in the top 28.5%.
Is Inspire Medical Systems' ROC (Joel Greenblatt) % too high?
Inspire Medical Systems' current ROC (Joel Greenblatt) % is -1.45%. Based on the distribution chart, Inspire Medical Systems ranks #239 out of 840 companies in the Medical Devices & Instruments industry, which is above the industry midpoint. Overall, Inspire Medical Systems has a GF Score™ of 59/100 and is considered Possible Value Trap, reflecting its overall financial health beyond just this single metric.
How does Inspire Medical Systems' ROC (Joel Greenblatt) % compare to ENOV and PRCT?
According to the Medical Devices & Instruments industry distribution chart, Inspire Medical Systems ranks #239 out of 840 companies for ROC (Joel Greenblatt) %. This puts Inspire Medical Systems in the upper half of its industry. The industry median ROC (Joel Greenblatt) % is 4.15. 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 4.15, based on 840 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. 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 Inspire Medical Systems and its competitors. For the Medical Devices & Instruments industry, the median ROC (Joel Greenblatt) % is 4.15 — values significantly above this may indicate overvaluation, while values below may suggest a bargain or underlying issues. Inspire Medical Systems's current ROC (Joel Greenblatt) % is -1.45%. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Inspire Medical Systems stock overvalued right now?
Based on GuruFocus' analysis, Inspire Medical Systems (STU:2DR) is currently considered Possible Value Trap. The stock's GF Value™ is €186.93, compared to a current price of €43.80 — trading 76.6% below its estimated fair value. The current ROC (Joel Greenblatt) % is -1.45%. Inspire Medical Systems' overall GF Score™ is 59/100 with 7 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 Inspire Medical Systems (STU:2DR), the current ROC (Joel Greenblatt) % is -1.45% 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 Inspire Medical Systems (STU:2DR) Overvalued in 2026?
Based on GuruFocus' analysis, Inspire Medical Systems stock appears to be undervalued.
The current stock price of €43.80 is trading 76.6% below its estimated GF Value™ of €186.93.
GuruFocus considers Inspire Medical Systems to be Possible Value Trap.
Key valuation signals for STU:2DR:
ROC (Joel Greenblatt) %: -1.45%
GF Value™: €186.93 vs. price of €43.80 (76.6% below fair value)
No single metric tells the full story. See the STU:2DR stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Inspire Medical Systems Inc operates as a medical technology company. It focuses on the development and commercialization of minimally invasive solutions for patients with obstructive sleep apnea (OSA). It offers Inspire system, a neurostimulation technology that provides a safe and effective treatment for moderate to severe obstructive sleep apnea. The firm has operating footprints in the United States and All other countries wherein, it generates a majority of its revenue from the United States. Its segment revenues are derived from the sales of its product, the Inspire system, to hospitals and ambulatory surgery centers in the U.S. and in selected countries in Europe and the Asia Pacific region.
59GF Score
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