Castle Biosciences (CSTL) Stock Price, News & Analysis

Company Overview

Castle Biosciences, Inc. is a molecular diagnostics company specializing in the development and commercialization of prognostic and diagnostic tests for patients with dermatologic conditions. The company’s proprietary portfolio of genomic assays is designed to improve risk assessment and guide clinical decision-making for individuals with skin cancers and other skin-related diseases. By combining genomic data with advanced statistical algorithms, Castle Biosciences seeks to provide actionable insights that help physicians tailor treatment plans and monitoring strategies.

The company’s flagship test, DecisionDx-Melanoma, evaluates the probability of metastasis in patients diagnosed with cutaneous melanoma, supporting more personalized surveillance and therapeutic approaches. In addition to its melanoma assay, Castle Biosciences offers DecisionDx-SCC for cutaneous squamous cell carcinoma and DecisionDx-Merkel for Merkel cell carcinoma. These tests leverage RNA expression profiling to stratify patients according to their individual risk profiles, enabling clinicians to determine optimal treatment intensity and follow-up schedules.

Founded in 2014 and headquartered in Friendswood, Texas, Castle Biosciences has expanded its operations across the United States, collaborating with dermatologists, oncologists and pathologists to integrate its tests into routine clinical practice. The company went public in 2017 and has since pursued strategic partnerships with academic medical centers and commercial laboratories to broaden access to its diagnostic services. Castle Biosciences maintains a robust intellectual property portfolio to protect its assay methodologies and ongoing research initiatives.

Guided by an experienced management team, Castle Biosciences continues to advance its pipeline of dermatologic tests and explore applications in other oncology and immune-mediated disease settings. The company’s leadership emphasizes rigorous clinical validation, regulatory compliance and payer engagement to support reimbursement and drive adoption of its genomic tests. Through ongoing research collaborations and real-world evidence generation, Castle Biosciences aims to refine its testing platforms and extend the clinical utility of molecular diagnostics in dermatology and beyond.

Key Stats

• Today's Range: $22.10 to $22.74
• 50-Day Range: $19.16 to $24.65
• 52-Week Range: $14.59 to $35.84
• Volume: 230,821 shs
• Average Volume: 296,420 shs
• Market Capitalization: $642.28 million
• P/E Ratio: N/A
• Dividend Yield: N/A
• Price Target: $36.57
• Consensus Rating: Moderate Buy

Castle Biosciences Stock Analysis - MarketRank™

Castle Biosciences scored higher than 62% of companies evaluated by MarketBeat, and ranked 389th out of 941 stocks in the medical sector. Scores are calculated by averaging available category scores, with extra weight given to analysis and valuation.

Analyst's Opinion

• Score: 3.9 / 5
• Analyst Rating: Moderate Buy

Consensus Rating

Castle Biosciences has received a consensus rating of Moderate Buy. The company's average rating score is 2.67, and is based on 7 buy ratings, 1 hold rating, and 1 sell rating.

Upside Potential

Castle Biosciences has a consensus price target of $36.57, representing about 65.2% upside from its current price of $22.14.

Amount of Analyst Coverage

Castle Biosciences has only been the subject of 3 research reports in the past 90 days.

Earnings and Valuation

• Score: 0.0 / 5
• Proj. Earnings Growth: Decreasing

Earnings Growth

Earnings for Castle Biosciences are expected to decrease in the coming year, from $0.44 to ($1.51) per share.

Price to Earnings Ratio vs. the Market

The P/E ratio of Castle Biosciences is -63.26, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.

Price to Earnings Ratio vs. Sector

The P/E ratio of Castle Biosciences is -63.26, which means that its earnings are negative and its P/E ratio cannot be compared to companies with positive earnings.

Price to Book Value per Share Ratio

Castle Biosciences has a P/B Ratio of 1.36. P/B Ratios below 3 indicates that a company is reasonably valued with respect to its assets and liabilities.

Short Interest

• Score: 4.0 / 5
• Short Interest Level: Healthy

Percentage of Shares Shorted

5.34% of the outstanding shares of Castle Biosciences have been sold short.

Short Interest Ratio / Days to Cover

Castle Biosciences has a short interest ratio ("days to cover") of 3.2, which is generally considered an acceptable ratio of short interest to trading volume.

Change versus previous month

Short interest in Castle Biosciences has recently decreased by 13.89%, indicating that investor sentiment is improving significantly.

Dividend

• Score: 0.0 / 5
• Dividend Strength: N/A

Dividend Yield

Castle Biosciences does not currently pay a dividend.

Dividend Growth

Castle Biosciences does not have a long track record of dividend growth.

Sustainability and ESG

• Score: N/A
• Environmental Score: N/A

Percentage of Shares Shorted

5.34% of the outstanding shares of Castle Biosciences have been sold short.

Short Interest Ratio / Days to Cover

Castle Biosciences has a short interest ratio ("days to cover") of 3.2, which is generally considered an acceptable ratio of short interest to trading volume.

Change versus previous month

Short interest in Castle Biosciences has recently decreased by 13.89%, indicating that investor sentiment is improving significantly.

News and Social Media

• Score: 2.8 / 5
• News Sentiment: 1.00

News Sentiment

Castle Biosciences has a news sentiment score of 1.00. This score is calculated as an average of sentiment of articles about the company over the last seven days and ranges from 2 (good news) to -2 (bad news). This is a higher news sentiment than the 0.46 average news sentiment score of Medical companies.

News Coverage This Week

MarketBeat has tracked 2 news articles for Castle Biosciences this week, compared to 5 articles on an average week.

Search Interest

Only 4 people have searched for CSTL on MarketBeat in the last 30 days. This is a decrease of -33% compared to the previous 30 days.

MarketBeat Follows

1 people have added Castle Biosciences to their MarketBeat watchlist in the last 30 days.

Company Ownership

• Score: 2.5 / 5
• Insider Trading: Selling Shares

Insider Buying vs. Insider Selling

In the past three months, Castle Biosciences insiders have sold more of their company's stock than they have bought. Specifically, they have bought $0.00 in company stock and sold $29,418.00 in company stock.

Percentage Held by Insiders

Only 6.50% of the stock of Castle Biosciences is held by insiders.

Percentage Held by Institutions

92.60% of the stock of Castle Biosciences is held by institutions. High institutional ownership can be a signal of strong market trust in this company.

CSTL Stock Analysis - Frequently Asked Questions

How have CSTL shares performed this year?

Castle Biosciences' stock was trading at $26.65 at the beginning of 2025. Since then, CSTL shares have decreased by 16.9% and is now trading at $22.14.

How were Castle Biosciences' earnings last quarter?

Castle Biosciences, Inc. (NASDAQ:CSTL) posted its earnings results on Monday, August, 4th. The company reported $0.15 earnings per share for the quarter, beating the consensus estimate of ($0.51) by $0.66. The business had revenue of $86.18 million for the quarter, compared to analysts' expectations of $71.53 million. Castle Biosciences had a negative net margin of 2.73% and a positive trailing twelve-month return on equity of 2.37%.
Read the conference call transcript.

When did Castle Biosciences IPO?

Castle Biosciences (CSTL) raised $50 million in an initial public offering on Thursday, July 25th 2019. The company issued 3,300,000 shares at a price of $14.00-$16.00 per share. SVB Leerink and Baird served as the underwriters for the IPO and Canaccord Genuity and BTIG were co-managers.

Who are Castle Biosciences' major shareholders?

Castle Biosciences' top institutional shareholders include Inspire Investing LLC (0.07%), Harbor Capital Advisors Inc. (0.05%), Green Alpha Advisors LLC (0.03%) and CWM LLC (0.01%). Insiders that own company stock include Kristen M Oelschlager, Derek J Maetzold, Tobin W Juvenal, Frank Stokes, Ellen Goldberg, Tiffany Olson and Daniel Bradbury.
View institutional ownership trends.

How do I buy shares of Castle Biosciences?

Shares of CSTL stock can be purchased through any online brokerage account. Popular online brokerages with access to the U.S. stock market include Charles Schwab, E*TRADE, Fidelity, and Vanguard Brokerage Services.

What other stocks do shareholders of Castle Biosciences own?

Based on aggregate information from My MarketBeat watchlists, some other companies that Castle Biosciences investors own include NVIDIA (NVDA), Meta Platforms (META), CrowdStrike (CRWD), PayPal (PYPL), Adobe (ADBE), Advanced Micro Devices (AMD) and Broadcom (AVGO).

Company Calendar

• Last Earnings: 8/04/2025
• Today: 10/18/2025
• Next Earnings (Estimated): 11/03/2025
• Fiscal Year End: 12/31/2025

Industry, Sector and Symbol

• Stock Exchange: NASDAQ
• Sector: Medical
• Industry: MED - BIOMED/GENE
• Sub-Industry: Healthcare
• Current Symbol: NASDAQ:CSTL
• CIK: 1447362
• Web: castlebiosciences.com
• Phone: (866) 788-9007
• Fax: N/A
• Employees: 540
• Year Founded: 2008

Price Target and Rating

• Average Price Target for Castle Biosciences: $36.57
• High Price Target: $41.00
• Low Price Target: $30.00
• Potential Upside/Downside: +65.2%
• Consensus Rating: Moderate Buy
• Rating Score (0-4): 2.67
• Research Coverage: 9 Analysts

Profitability

• EPS (Trailing Twelve Months): ($0.35)
• Trailing P/E Ratio: N/A
• Forward P/E Ratio: 50.32
• P/E Growth: N/A
• Net Income: $18.25 million
• Net Margins: -2.73%
• Pretax Margin: -2.96%
• Return on Equity: 2.37%
• Return on Assets: 2.03%

Debt

• Debt-to-Equity Ratio: 0.02
• Current Ratio: 6.85
• Quick Ratio: 6.69

Sales & Book Value

• Annual Sales: $332.07 million
• Price / Sales: 1.93
• Cash Flow: $0.97 per share
• Price / Cash Flow: 22.90
• Book Value: $16.28 per share
• Price / Book: 1.36

Miscellaneous

• Outstanding Shares: 29,010,000
• Free Float: 27,122,000
• Market Cap: $642.28 million
• Optionable: Optionable
• Beta: 1.13