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Shares outstanding are shares that have been authorized, issued, and purchased by investors and are held by them. Castle Biosciences's average diluted shares outstanding for the quarter that ended in Jun. 2026 was 30.4 Mil.
A company may buy back shares or issue shares in any fiscal period. If a company buys back shares, we should observe that the total number of shares decline. If the company issues new shares, the number of shares outstanding increases.
Be Aware
Usually the presence of treasury shares and a history of buyback are good indicators that company has competitive advantage. But studies have shown that companies usually buy back at wrong time. Buying back shares below its intrinsic value increases value for remaining shareholders. Buying back overvalued shares destroys value for existing shareholders.
Castle Biosciences Shares Outstanding (Diluted Average) Related Terms
Castle Biosciences Shares Outstanding (Diluted Average) Historical Data
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The historical data trend for Castle Biosciences's Shares Outstanding (Diluted Average) 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.
Shares outstanding are shares that have been authorized, issued, and purchased by investors and are held by them. They have voting rights and represent ownership in the corporation by the person that holds the shares. They should be distinguished from treasury shares, which are shares held by the corporation itself, having no exercisable rights.
Shares outstanding can be calculated as either basic or fully diluted. The fully diluted shares outstanding count includes diluting securities, such as options, warrants or convertibles.
Please note: GuruFocus named Shares Outstanding (EOP) is the shares for that exact time point. It is usually used to calculate balance sheet related items, such as Book Value per Share, etc. While Shares Outstanding (Diluted Average) and Shares Outstanding (Basic Average) are the weighted average shares over a period of time (a year, a quarter, or so). They are usually used to calculate income statement or cashflow statement related items, such as Earnings per Share (Diluted), etc.
What does a Shares Outstanding (Diluted Average) of 30.4 Mil mean?
Castle Biosciences (CSTL) has a Shares Outstanding (Diluted Average) of 30.4 Mil as of Jun. 2026. The average shares outstanding over two periods including dilutive securities like preferred shares and convertibles. View historical data on Castle Biosciences and its competitors.
Is Castle Biosciences' Shares Outstanding (Diluted Average) too high?
Castle Biosciences' current Shares Outstanding (Diluted Average) is 30.4 Mil. Overall, Castle Biosciences has a GF Score™ of 81/100 and is considered Fairly Valued, reflecting its overall financial health beyond just this single metric.
How does Castle Biosciences' Shares Outstanding (Diluted Average) compare to OPK and FLGT?
Castle Biosciences' Shares Outstanding (Diluted Average) of 30.4 Mil can be compared against companies in the Medical Diagnostics & Research industry. See the competitive comparison table and distribution chart on this page for a detailed peer-by-peer breakdown.
What is a good Shares Outstanding (Diluted Average) for a Medical Diagnostics & Research company?
A good Shares Outstanding (Diluted Average) depends on the Medical Diagnostics & Research industry context. However, Shares Outstanding (Diluted Average) 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 Shares Outstanding (Diluted Average) mean?
A high Shares Outstanding (Diluted Average) can signal that a stock is expensive relative to its fundamentals. The average shares outstanding over two periods including dilutive securities like preferred shares and convertibles. View historical data on Castle Biosciences and its competitors. Castle Biosciences's current Shares Outstanding (Diluted Average) is 30.4 Mil. 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 Fairly Valued. The stock's GF Value™ is $29.40, compared to a current price of $28.00 — trading 4.8% below its estimated fair value. The current Shares Outstanding (Diluted Average) is 30.4 Mil. 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 Shares Outstanding (Diluted Average) calculated?
Shares Outstanding (Diluted Average) is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current Shares Outstanding (Diluted Average) is 30.4 Mil as of Jun. 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 $28.00 is trading 4.8% below its estimated GF Value™ of $29.40.
GuruFocus considers Castle Biosciences to be Fairly Valued.
Key valuation signals for CSTL:
Shares Outstanding (Diluted Average): 30.4 Mil
GF Value™: $29.40 vs. price of $28.00 (4.8% 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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