Castle Biosciences's book value per share for the quarter that ended in Mar. 2026 was $15.23.
During the past 12 months, Castle Biosciences's average Book Value Per Share Growth Rate was -0.20% per year.
During the past 3 years, the average Book Value Per Share Growth Rate was 1.80% per year.
During the past 5 years, the average Book Value Per Share Growth Rate was -1.00% per year.
Please click Growth Rate Calculation Example (GuruFocus) to see how GuruFocus calculates Wal-Mart Stores Inc (WMT)'s revenue growth rate. You can apply the same method to get the book value growth rate using book value per share data.
During the past 9 years, the highest 3-Year average Book Value Per Share Growth Rate of Castle Biosciences was 44.60% per year. The lowest was -5.20% per year. And the median was 0.65% per year.
Castle Biosciences's current price is $24.725. Its book value per share for the quarter that ended in Mar. 2026 was $15.23. Hence, today's PB Ratio of Castle Biosciences is 1.62.
During the past 9 years, the highest P/B Ratio of Castle Biosciences was 8.50. The lowest was 0.86. And the median was 1.77.
Castle Biosciences (NAS:CSTL) Book Value per Share Explanation
Usually a company's book value and Tangible Book per Share may not reflect its true value. The assets may be carried on the balance sheets at the original cost minus depreciation. This may underestimate the true economic values of the assets. It also may over-estimate their true economic value because the assets can become obsolete.
For financial companies such as banks and insurance companies, their assets may be reported in current market value of the assets owned. Book values of financial companies are more accurate indicator of the economic value of the company.
Castle Biosciences Book Value per Share Related Terms
Castle Biosciences Book Value per Share Historical Data
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The historical data trend for Castle Biosciences's Book Value per Share 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.
CSTL vs FLGT, MYGN, OPK: Book Value per Share Comparison
For the Diagnostics & Research subindustry, Castle Biosciences's PB Ratio, along with its competitors' market caps and PB Ratio 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 PB Ratio vs Medical Diagnostics & Research Industry
For the Medical Diagnostics & Research industry and Healthcare sector, Castle Biosciences's PB Ratio distribution charts can be found below:
* The bar in red indicates where Castle Biosciences's PB Ratio 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.
Castle Biosciences (CSTL) has a Book Value per Share of $15.23 as of Mar. 2026. Book value per share gives the per-share value of a company's stockholder equity. View historical data on Castle Biosciences and its competitors.
Is Castle Biosciences' Book Value per Share too high?
Castle Biosciences' current Book Value per Share is $15.23. Overall, Castle Biosciences has a GF Score™ of 77/100 and is considered Modestly Undervalued, reflecting its overall financial health beyond just this single metric.
How does Castle Biosciences' Book Value per Share compare to FLGT and MYGN?
Castle Biosciences' Book Value per Share of $15.23 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 Book Value per Share for a Medical Diagnostics & Research company?
A good Book Value per Share depends on the Medical Diagnostics & Research industry context. However, Book Value per Share 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 Book Value per Share mean?
A high Book Value per Share can signal that a stock is expensive relative to its fundamentals. Book value per share gives the per-share value of a company's stockholder equity. View historical data on Castle Biosciences and its competitors. Castle Biosciences's current Book Value per Share is $15.23. 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 $29.19, compared to a current price of $24.73 — trading 15.3% below its estimated fair value. The current Book Value per Share is $15.23. Castle Biosciences' overall GF Score™ is 77/100 with 4 warning signs to review. Investors should evaluate multiple metrics — including profitability, growth, and financial strength — before making a decision.
How is Book Value per Share calculated?
Book Value per Share is calculated from a company's financial statements. For Castle Biosciences (CSTL), the current Book Value per Share is $15.23 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 $24.73 is trading 15.3% below its estimated GF Value™ of $29.19.
GuruFocus considers Castle Biosciences to be Modestly Undervalued.
Key valuation signals for CSTL:
Book Value per Share: $15.23
GF Value™: $29.19 vs. price of $24.73 (15.3% 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.
77GF Score
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