CSTL Stock Analysis: Castle Biosciences | NASDAQ

Diagnostics & Research | NASDAQ, USA | Market Cap: 734m USD | 12M Return: 19.6% | Charts, Fundamentals & Technical Analysis

Diagnostics, Oncology, Dermatology, Gastroenterology
Total Rating 42
Safety 87
Buy Signal -0.45
Diagnostics & Research
Industry Rotation: -2.6
Market Cap: 734M
Avg Turnover: 7.22M
Risk 3d forecast
Volatility59.1%
VaR 5th Pctl9.18%
VaR vs Median-4.94%
Reward TTM
Sharpe Ratio0.52
Rel. Str. IBD22
Rel. Str. Peer Group11.8
Character TTM
Beta0.135
Beta Downside-0.071
Hurst Exponent0.487
Drawdowns 3y
Max DD57.83%
CAGR/Max DD0.25
CAGR/Mean DD0.64
EPS (Earnings per Share) EPS (Earnings per Share) of CSTL over the last years for every Quarter: "2021-06": -0.35, "2021-09": -0.47, "2021-12": -0.25, "2022-03": -0.97, "2022-06": -0.06, "2022-09": -0.77, "2022-12": -0.78, "2023-03": -1.1, "2023-06": -0.7, "2023-09": -0.26, "2023-12": -0.1, "2024-03": -0.09, "2024-06": 0.31, "2024-09": 0.08, "2024-12": 0.32, "2025-03": -0.9, "2025-06": 0.15, "2025-09": -0.02, "2025-12": -0.08, "2026-03": -0.49,
Last SUE: 0.00
Qual. Beats: 0
Revenue Revenue of CSTL over the last years for every Quarter: 2021-06: 22.758, 2021-09: 23.475, 2021-12: 25.039, 2022-03: 26.852, 2022-06: 34.838, 2022-09: 37.011, 2022-12: 38.338, 2023-03: 42.037, 2023-06: 50.138, 2023-09: 61.493, 2023-12: 66.12, 2024-03: 72.974, 2024-06: 87.002, 2024-09: 85.782, 2024-12: 86.311, 2025-03: 87.988, 2025-06: 86.188, 2025-09: 83.043, 2025-12: 87.01, 2026-03: 83.679,
Rev. CAGR: 29.36%
Rev. Trend: 90.0%
Last SUE: 0.74
Qual. Beats: 0

Warnings

High Debt/EBITDA With Thin Interest Coverage
Interest Coverage Ratio Critical
Below Sma 200d

Tailwinds

No distinct edge detected

Seasonality 6.9 years of data

Jan +3.3% 37
Feb -15.6% 24
Mar -5.8% 17
Apr -0.6% 0
May -6.6% 18
Jun +4.7% 0
Jul +1.3% 2
Aug +14.4% 61
Sep -10.3% 27
Oct -3.0% 16
Nov -3.9% 15
Dec +2.1% 17

How good or bad each month usually is (without trend). The score below shows how much you can trust it: 0 = pure chance, >40 gets interesting and >55 is strong.

Description: CSTL Castle Biosciences

Castle Biosciences is a molecular diagnostics company that develops and commercializes gene expression profile (GEP) tests and related tissue-based assays. Its flagship DecisionDx-Melanoma test predicts the risk of sentinel lymph node positivity and metastasis in invasive cutaneous melanoma, while DecisionDx-SCC addresses risk stratification in cutaneous squamous cell carcinoma. The company has expanded into adjacent indications with TissueCypher for Barretts esophagus, AdvanceAD-Tx for atopic dermatitis, and DecisionDx-UM for uveal melanoma, selling primarily to dermatology and gastroenterology practices. Founded in 2007 and headquartered in Friendswood, Texas, Castle Biosciences went public on Nasdaq in 2019.

As a clinical GEP-based diagnostics business, the company operates in the dermatology and gastroenterology markets, generating revenue primarily through per-test reimbursement from commercial and Medicare payers. Because the tests are physician-ordered and patient-specific, the business model relies on clinical adoption, inclusion in treatment guidelines, and favorable coverage decisions to drive recurring test volume.

Headlines to Watch Out For
  • DecisionDx-Melanoma test volume growth drives dermatology segment revenue
  • TissueCypher Barretts esophagus adoption accelerates gastroenterology sales
  • NCCN guideline inclusion expands reimbursement coverage and physician adoption
Piotroski VR-10 (Strict) 1.0
Net Income: -12.8m TTM > 0 and > 6% of Revenue
FCF/TA: 0.01 > 0.02 and ΔFCF/TA -7.50 > 1.0
NWC/Revenue: 82.41% < 20% (prev 89.92%; Δ -7.51% < -1%)
CFO/TA 0.09 > 3% & CFO 48.3m > Net Income -12.8m
Net Debt/EBITDA: error (EBITDA <= 0)
Current Ratio: 6.75 > 1.5 & < 3
Outstanding Shares: last quarter (29.9m) vs 12m ago 4.47% < -2%
Gross Margin: 77.07% > 18% (prev 81.94%; Δ -4.87% > 0.5%)
Asset Turnover: 64.78% > 50% (prev 69.18%; Δ -4.40% > 0%)
Interest Coverage Ratio: -86.09 > 6 (EBIT TTM -17.5m / Interest Expense TTM 203k)
Altman Z'' 7.32
A: 0.51 (Total Current Assets 328.9m - Total Current Liabilities 48.8m) / Total Assets 547.8m
B: -0.44 (Retained Earnings -238.8m / Total Assets 547.8m)
C: -0.03 (EBIT TTM -17.5m / Avg Total Assets 524.8m)
D: 5.34 (Book Value of Equity 461.4m / Total Liabilities 86.4m)
Altman-Z'' = 7.32 = AAA
Beneish M -3.13
DSRI: 0.77 (Receivables 42.3m/56.4m, Revenue 339.9m/347.1m)
GMI: 1.06 (GM 81.94% / 77.07%)
AQI: 1.11 (AQ_t 0.19 / AQ_t-1 0.17)
SGI: 0.98 (Revenue 339.9m / 347.1m)
TATA: -0.11 (NI -12.8m - CFO 48.3m) / TA 547.8m)
Beneish M = -3.13 (Cap -4..+1) = AA
What is the price of CSTL shares?

As of July 11, 2026, the stock is trading at USD 23.72 with a total of 200,770 shares traded. Over the past week, the price has changed by -1.62%, over one month by +12.52%, over three months by +2.55% and over the past year by +19.56%.

Current recommended Stop Loss: 22.50 (which is 5.1% or 1.2 ATR below the current price).

Is CSTL a buy, sell or hold?

Castle Biosciences has received a consensus analysts rating of 4.89. Therefore, it is recommended to buy CSTL.

  • StrongBuy: 8
  • Buy: 1
  • Hold: 0
  • Sell: 0
  • StrongSell: 0

What are the forecasts/targets for the CSTL price?
Analysts Target Price 43.6 83.6%
Castle Biosciences (CSTL) - Fundamental Data Overview as of 08 July 2026
Market Cap USD = 734.3m (734.3m USD * 1.0 USD.USD)
P/S = 2.1602
P/B = 1.5848
Revenue TTM = 339.9m USD
EBIT TTM = -17.5m USD
EBITDA TTM = -726k USD
Long Term Debt = 8.40m USD (from longTermDebt, last quarter)
Short Term Debt = 2.92m USD (from shortTermDebt, last quarter)
Debt = 63.4m USD (from shortLongTermDebtTotal, last quarter) + Leases 26.7m
Net Debt = -198.3m USD (calculated: Debt 63.4m - CCE 261.7m)
Enterprise Value = 536.0m USD (734.3m + Debt 63.4m - CCE 261.7m)
Interest Coverage Ratio = -86.09 (Ebit TTM -17.5m / Interest Expense TTM 203k)
EV/FCF = 118.6x (Enterprise Value 536.0m / FCF TTM 4.52m)
FCF Yield = 0.84% (FCF TTM 4.52m / Enterprise Value 536.0m)
FCF Margin = 1.33% (FCF TTM 4.52m / Revenue TTM 339.9m)
Net Margin = -3.78% (Net Income TTM -12.8m / Revenue TTM 339.9m)
Gross Margin = 77.07% ((Revenue TTM 339.9m - Cost of Revenue TTM 77.9m) / Revenue TTM)
Gross Margin QoQ = 72.15% (prev 78.95%)
Tobins Q-Ratio = 0.98 (Enterprise Value 536.0m / Total Assets 547.8m)
Interest Expense / Debt = 0.32% (Interest Expense 203k / Debt 63.4m)
Taxrate = 21.0% (US federal default 21%)
NOPAT = -13.8m (EBIT -17.5m * (1 - 21.00%)) [loss with tax shield]
Current Ratio = 6.75 (Total Current Assets 328.9m / Total Current Liabilities 48.8m)
Debt / Equity = 0.14 (Debt 63.4m / totalStockholderEquity, last quarter 461.4m)
 Debt / EBITDA = 273.3 (negative EBITDA) (Net Debt -198.3m / EBITDA -726k)
 Debt / FCF = -43.89 (Net Debt -198.3m / FCF TTM 4.52m)
Total Stockholder Equity = 463.7m (last 4 quarters mean from totalStockholderEquity)
RoA = -2.45% (Net Income -12.8m / Total Assets 547.8m)
RoE = -2.77% (Net Income TTM -12.8m / Total Stockholder Equity 463.7m)
RoCE = -3.70% (EBIT -17.5m / Capital Employed (Equity 463.7m + L.T.Debt 8.40m))
 RoIC = -2.85% (negative operating profit) (NOPAT -13.8m / Invested Capital 485.0m)
 WACC = 5.97% (E(734.3m)/V(797.7m) * Re(6.46%) + D(63.4m)/V(797.7m) * Rd(0.32%) * (1-Tc(0.21)))
Discount Rate = 6.46% (= CAPM, Blume Beta Adj.)
Shares (quarterly) Correlation: 51.11 | Cagr: 4.38%
[DCF] Terminal Value 73.10% ; FCFF base≈19.4m ; Y1≈17.0m ; Y5≈13.8m
[DCF] Fair Price = 13.82 (EV 220.8m - Net Debt -198.3m = Equity 419.1m / Shares 30.3m; r=8.35% [WACC [floored]]; 5y FCF grow -15.0% → 2.50% )
EPS Correlation: N/A | EPS CAGR: N/A | SUE: 0.0 | # QB: 0
Revenue Correlation: 90.01 | Revenue CAGR: 29.36% | SUE: 0.74 | # QB: 0
EPS current Quarter (2026-06-30): EPS=-0.40 | Chg30d=-1.18% | Revisions=-36% | Analysts=9
EPS next Quarter (2026-09-30): EPS=-0.30 | Chg30d=-1.44% | Revisions=-36% | Analysts=9
EPS current Year (2026-12-31): EPS=-1.40 | Chg30d=-1.40% | Revisions=-18% | GrowthEPS=-69.2% | GrowthRev=+2.5%
EPS next Year (2027-12-31): EPS=-0.93 | Chg30d=-0.35% | Revisions=-36% | GrowthEPS=+33.5% | GrowthRev=+11.6%
[Analyst] Revisions Ratio: -40% (up=9, down=23)