Castle Biosciences, Inc. (CSTL) AI Stock Analysis

Castle Biosciences, Inc. is a diagnostics company specializing in advanced testing services for dermatological cancers. The company delivers diagnostic and prognostic solutions designed to assist treatment decisions for patients with skin cancer diagnoses. Its flagship test, DecisionDx-Melanoma, evaluates metastatic risk in invasive cutaneous melanoma. Castle Biosciences also provides DecisionDx-UM for uveal melanoma, DecisionDx-SCC for squamous cell carcinoma, and DecisionDx DiffDx-Melanoma alongside myPath Melanoma for characterizing suspicious pigmented lesions. Through partnerships with physicians, the company provides these testing services to support personalized clinical care.

Annual revenue increased from $94.1M in FY2021 to $332.1M in FY2024, reaching $344.2M in FY2025, which reflects a 5-year CAGR of 40.6%. Annual revenue growth slowed from 51.1% in FY2024 to 3.7% in FY2025. Gross margins have stayed elevated, registering 79.4% in FY2025 compared to 81.9% in FY2024. After achieving net income of $18.2M and an operating margin of 2.6% in FY2024, Castle Biosciences posted a net loss of -$24.2M and an operating margin of -12.4% in FY2025. For the trailing twelve months ended June 30, 2026, revenue stood at $357.3M with a profit margin of -5.4%. In the latest quarter, revenue grew 20.1% year-over-year while earnings fell 51.6%.

As of June 30, 2026, Castle Biosciences held $266.8M in cash and short-term investments and $36.6M in total debt, yielding net cash of $230.2M. Liquidity is supported by a current ratio of 6.04 and a debt-to-equity ratio of 0.08 against shareholders' equity of $470.0M. In FY2025, the company generated $64.3M in operating cash flow and $28.3M in free cash flow. Capital expenditures were $36.0M in FY2025, while the company's share count increased 20.0% over 5 years.

Castle Biosciences trades at a price-to-sales multiple of 2.7x and an enterprise value to revenue ratio of 2.3x, below the US-listed Healthcare median price-to-sales ratio of 4.1x. Its EV-to-EBITDA ratio of 43.0x is higher than the US-listed Healthcare median of 12.0x, alongside a price-to-book ratio of 2.3x. Over the past 12 months, CSTL stock advanced 41.9%, outperforming the S&P 500 (SPY) return of 16.8%. However, over a 5-year period, the stock fell 49.7%, trailing the S&P 500 return of 83.0%.

Consensus ratings include 9 Strong Buy recommendations, with 0 Buy, 0 Hold, 0 Sell, and 0 Strong Sell ratings. The mean price target of $45.22 reflects an implied upside of 41.5% from the October 16, 2026 close of $31.96. For the fiscal year ending December 31, 2026, analysts estimate revenue of $373.5M and an EPS of -$1.26. For the next fiscal year, 9 analysts project revenue of $412.5M. Castle Biosciences beat EPS estimates in 3 of the last 4 quarters, with its next earnings date scheduled for November 5, 2026.

This page is an AI-written research summary of Castle Biosciences, Inc. (CSTL). The text was generated on October 30, 2026 from Quotelinks data as of October 16, 2026 (company profile, annual results, latest balance sheet, valuation, price performance and analyst estimates). An automatic check rejects any draft that contains a figure not found in that data. It is not investment advice; verify figures on the linked tabs before making decisions.

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