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Castle Biosciences has the Profitability Rank of 3. It has had trouble to make a profit.
GuruFocus Profitability Rank ranks how profitable a company is and how likely the company's business will stay that way. It is rated on a scale of 1 to 10 and is based on these factors:
1. Operating Margin %
2. Piotroski F-Score
3. Trend of the Operating Margin % (5-year average). The company with an uptrend profit margin has a higher rank.
4. Consistency of the profitability
5. Predictability Rank
A higher score indicates superior profitability, with companies rated 7 or above considered to have more robust and sustainable profit generation. Conversely, a score of 3 or lower suggests challenges in generating consistent profits.
Castle Biosciences Profitability Rank Related Terms
CSTL vs OPK, FLGT, MYGN: Profitability Rank Comparison
For the Diagnostics & Research subindustry, Castle Biosciences's Profitability Rank, along with its competitors' market caps and Profitability Rank 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.
Castle Biosciences Profitability Rank vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Castle Biosciences's Profitability Rank distribution charts can be found below:
* The bar in red indicates where Castle Biosciences's Profitability Rank falls into.
GuruFocus Profitability Rank ranks how profitable a company is and how likely the company's business will stay that way.
The rank is rated on a scale of 1 to 10. A higher score indicates superior profitability, with companies rated 7 or above considered to have more robust and sustainable profit generation. Conversely, a score of 3 or lower suggests challenges in generating consistent profits.
Castle Biosciences has the Profitability Rank of 3. It has had trouble to make a profit.
Profitability Rank is not directly related to the Financial Strength. But if a company is consistently profitable, its financial strength will be stronger.
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.
* 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.
Castle Biosciences (CSTL) has a Profitability Rank of 3 as of Mar. 2026. Profitability and Growth ranks a company based on its profit margins and earnings growth. View historical data on Castle Biosciences and its competitors. This is near median its historical median of 3.00. Over the past decade, Castle Biosciences' Profitability Rank has ranged from 1.00 to 4.00.
Is Castle Biosciences' Profitability Rank too high?
Castle Biosciences' current Profitability Rank of 3 is near median its 10-year median of 3.00. Over the past 10 years, this metric has ranged from a low of 1.00 to a high of 4.00. Overall, Castle Biosciences has a GF Score™ of 81/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Castle Biosciences' Profitability Rank compare to OPK and FLGT?
Castle Biosciences' Profitability Rank of 3 can be compared against companies in the Medical Diagnostics & Research industry. Historically, Castle Biosciences' own Profitability Rank has ranged from 1.00 to 4.00 over the past decade. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Profitability Rank for a Medical Diagnostics & Research company?
A good Profitability Rank depends on the Medical Diagnostics & Research industry context. However, Profitability Rank 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 Profitability Rank mean?
A high Profitability Rank can signal that a stock is expensive relative to its fundamentals. Profitability and Growth ranks a company based on its profit margins and earnings growth. View historical data on Castle Biosciences and its competitors. Castle Biosciences's current Profitability Rank is 3, which is near median its own 10-year median of 3.00. However, context matters — high-growth companies often justify higher valuations. Always evaluate alongside other metrics like GF Score™ and GF Value™.
Is Castle Biosciences stock overvalued right now?
Based on GuruFocus' analysis, Castle Biosciences (CSTL) is currently considered Modestly Undervalued. The stock's GF Value™ is $29.23, compared to a current price of $24.46 — trading 16.3% below its estimated fair value. The current Profitability Rank is 3, which is near median its 10-year median of 3.00. Castle Biosciences' overall GF Score™ is 81/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Profitability Rank calculated?
Profitability Rank is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current Profitability Rank is 3 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 Castle Biosciences (CSTL) Overvalued in 2026?
Based on GuruFocus' analysis, Castle Biosciences stock appears to be undervalued.
The current stock price of $24.46 is trading 16.3% below its estimated GF Value™ of $29.23.
GuruFocus considers Castle Biosciences to be Modestly Undervalued.
Key valuation signals for CSTL:
Profitability Rank: 3 (near median its 10-year median of 3.00)
GF Value™: $29.23 vs. price of $24.46 (16.3% below fair value)
No single metric tells the full story. See the CSTL stock analysis page for a complete view including 30-year financials, guru trades, and insider activity.
Castle Biosciences Inc is a molecular diagnostics company. The group provides test solutions for the diagnosis and treatment of dermatologic cancers, Barrett's esophagus (BE), and uveal melanoma. The product portfolio of the company includes DecisionDx-Melanoma, a risk stratification gene expression profile (GEP) test; DecisionDx-SCC, a risk stratification test for cutaneous squamous cell carcinoma; MyPath Melanoma, a diagnostic GEP test for use in patients with difficult-to-diagnose melanocytic lesions; and TissueCypher, a test to predict future development of progression of high-grade dysplasia and/or esophageal cancer. The company derives revenues through the delivery of test reports for its molecular diagnostic tests.
81GF Score
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