Healthcare · Medical - Diagnostics & Research
Price
$24.30
Market Cap
$737.0M
Employees
784
Beta
1.02
Avg Volume
390,517
CEO
Derek J. Maetzold
Business Description
Castle Biosciences, Inc. functions as a commercial-stage diagnostics firm, with its primary objective being the provision of both diagnostic and prognostic testing services, specifically targeting various dermatological cancers. Their flagship product, DecisionDx-Melanoma, represents an advanced multi-gene expression profile (GEP) assay engineered to assess the probability of metastasis in patients afflicted with invasive cutaneous melanoma. In addition to their leading solution, the company has created several other specialized, proprietary tests. Among these is DecisionDx-UM, a GEP test tailored to forecast the risk of metastasis for individuals with uveal melanoma, a less common malignancy of the eye. Another key offering is DecisionDx-SCC, a distinctive 40-gene expression profile test that utilizes a patient's unique tumor biology to predict their specific risk of squamous cell carcinoma metastasis, particularly for those presenting with recognized risk factors. Moreover, they offer DecisionDx DiffDx-Melanoma and myPath Melanoma, both proprietary GEP tests employed to assist in the accurate diagnosis of ambiguous pigmented lesions. These specialized testing services are provided by Castle Biosciences to patients predominantly through their healthcare providers. The organization commenced operations in 2007 and maintains its corporate headquarters in Friendswood, Texas.
Business History
Price Overview
Last updated: Jun 27, 2026 10:08am (just now)$24.30
+1.39 (+6.07%)
Day Range
$22.67 – $24.34
52-Week Range
$14.59 – $44.28
50-Day MA
$21.78
200-Day MA
$28.67
Volume
928,483.00
Analyst Price Targets
Low
$35.00
Consensus
$42.80
High
$52.00
(18 analysts)
Share Structure
Outstanding
30,329,952.00
Float
26,778,011.00
Free Float
88.3%
High free float
— 88.3% of shares trade freely, ~11.7% held by insiders/institutions
Very liquid — most shares trade freely. Low insider ownership can mean less management alignment, but makes large position sizing straightforward.
Price History (1 Year)
Revenue & Net Income Trend
The directional story — useful even when net income is negative.
Revenue
The top line — total sales before any costs or taxes are subtracted. A measure of how much business the company is doing.
Net Income
The bottom line — profit left after subtracting all expenses, interest, and taxes from revenue. Reflects accounting profitability, but includes non-cash items like depreciation, so it isn't the same as cash earned.
Operating Cash Flow
The real cash generated by the day-to-day business — selling products, paying suppliers, collecting from customers. Calculated from net income by adding back non-cash items and adjusting for timing (unpaid bills, unsold inventory). When OCF consistently lags net income, the reported profit may not be converting to real money.
| Period | Revenue | Net Income | Net Margin | YoY/QoQ |
|---|
Key Metrics
API Direct from provider
CALC Derived from statements
P/E Ratio (Price per dollar of earnings)
CALCStock Price / EPS (Diluted)
-29.28
Stock Price: $24.30
EPS (Diluted): -0.83
EPS (Diluted): -0.83
P/B Ratio (Price vs net asset value)
APIStock Price / Book Value Per Share
2.39
Stock Price: $24.30
Total Equity: $470.87M
Shares: 28,986,000
Total Equity: $470.87M
Shares: 28,986,000
EV/EBITDA (Total value vs operating profit)
APIEnterprise Value / EBITDA
-978.37
Market Cap: $737.02M
Total Debt: $10.06M
Cash: $116.73M
EBITDA: $11.34M
Total Debt: $10.06M
Cash: $116.73M
EBITDA: $11.34M
Enterprise Value (Takeover price (cap + debt - cash))
APIMarket Cap + Total Debt - Cash
$1.0B
Market Cap: $737.02M
Total Debt: $10.06M
Cash: $116.73M
Total Debt: $10.06M
Cash: $116.73M
P/S Ratio (Price per dollar of revenue)
APIStock Price / Revenue Per Share
3.28
Stock Price: $24.30
Revenue: $344.23M
Shares: 28,986,000
Revenue: $344.23M
Shares: 28,986,000
EV/Sales (Total value vs revenue — works when P/E can't)
API3.04
Gross Margin (Revenue left after direct costs)
APIGross Profit / Revenue
79.4%
Gross Profit: $273.20M
Revenue: $344.23M
Revenue: $344.23M
Operating Margin (Revenue left after all operations)
APIOperating Income / Revenue
-12.4%
Operating Income: -$42.81M
Revenue: $344.23M
Revenue: $344.23M
Net Margin (Revenue left as actual profit)
APINet Income / Revenue
-7.0%
Net Income: -$24.16M
Revenue: $344.23M
Revenue: $344.23M
ROE (Profit from shareholder equity)
APINet Income / Total Equity
-2.8%
Net Income: -$24.16M
Total Equity: $470.87M
Total Equity: $470.87M
ROIC (Profit from all invested capital)
APINOPAT / Invested Capital
-4.8%
Operating Income: -$42.81M
Tax Rate: 18.1%
Equity: $470.87M
Total Debt: $10.06M
Cash: $116.73M
Tax Rate: 18.1%
Equity: $470.87M
Total Debt: $10.06M
Cash: $116.73M
Current Ratio (Can it pay short-term bills)
APICurrent Assets / Current Liabilities
5.26
Current Assets: $361.10M
Current Liabilities: $68.68M
Current Liabilities: $68.68M
Debt/Equity (Leverage — debt vs equity)
CALCTotal Debt / Total Equity
0.02
Short-Term Debt: $417,000
Long-Term Debt: $9.64M
Total Debt: $10.06M
Total Equity: $470.87M
Long-Term Debt: $9.64M
Total Debt: $10.06M
Total Equity: $470.87M
Rev/Share (Top-line per share)
CALCRevenue / Shares Outstanding
$11.88
Revenue: $344.23M
Shares: 28,986,000
Shares: 28,986,000
Book Value/Share (Net assets per share)
CALC(Total Assets - Total Liabilities) / Shares
$16.24
Total Equity: $470.87M
Shares: 28,986,000
Shares: 28,986,000
FCF/Share (Real cash generated per share)
CALC(Operating Cash Flow + CapEx) / Shares
$0.98
Operating CF: $64.35M
CapEx: -$36.02M
Shares: 28,986,000
CapEx: -$36.02M
Shares: 28,986,000
CapEx is negative (outflow) — added to OCF to get FCF
Div Yield (Annual income from holding)
APILast Annual Dividend / Stock Price
0.0%
Last Dividend: N/A
Stock Price: $24.30
Stock Price: $24.30
Payout Ratio (Earnings paid out as dividends)
Dividends Paid / Net Income
—
Dividends Paid: N/A
Net Income: -$24.16M
Net Income: -$24.16M
Dividends paid not available in cash flow statement
Industry Benchmarks
Compares CSTL against LLM-researched typical ranges for its
industry. One research call per industry, cached indefinitely — every stock in the same industry
reuses the same baseline.
Deep Analysis
Pre-flight intelligence scans the company first, then routes to the right analytical methods.
0
Company Classification
— What type of company is this?
1
Industry Landscape
— Where is the industry headed?
2
Company Momentum
— Where is this company trending?
3
Forward Projection
— 1Y & 2Y projected metrics (requires Layer 1 + 2)
4a
DCF Valuation
— Present value of future cash flows
4b
Earnings Power Value
— Floor value — worth with zero growth
4c
Anchored PE
— Industry PE adjusted for growth differential
4d
Reverse DCF
— What growth is the market pricing in?
4e
Revenue-Based DCF
— For growth/narrative companies (skip if mature earner)
4f
Anchored P/S
— Price-to-Sales peer comparison (skip if mature earner)
4g
Scenario Analysis
— Bull / Base / Bear (skip if mature earner)
4h
Dividend Discount Model
— For dividend/income stocks only
4i
Book Value Analysis
— For deep value / turnaround stocks only
4j
Insider Activity
— Are insiders buying or selling?
4f
Cash Flow Quality
— How trustworthy is the FCF?
4g
Debt Maturity Risk
— Can it handle its debt?
4h
Macro Environment
— Rates, market valuation, volatility
4i
Sector Intelligence
— How does this company compare within its sector?
4j
Revenue Confidence
— How reliable is the growth projection?
4k
Sensitivity Analysis
— How fragile is the fair value estimate?
4l
Sector Demand Cycle
— Is the sector in a boom, steady state, or contraction?
5
AI Investigation
— Adaptive research engine (Claude)
5b
Thesis Evaluation
— What does the market believe? (narrative/platform stocks only)
6
Valuation Synthesis
— Weighted verdict from all methods (requires Layer 4)
Income Statement (Annual)
Last updated: Jun 27, 2026 10:08am (just now)| Metric | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|
| Revenue | $94.1M | $137.0M | $219.8M | $332.1M | $344.2M |
| Cost of Revenue | $15.8M | $32.0M | $45.0M | $60.2M | $71.0M |
| Gross Profit | $78.3M | $105.0M | $174.8M | $271.9M | $273.2M |
| Operating Expenses | $118.3M | $177.9M | $242.8M | $263.2M | $316.0M |
| Operating Income | -$40.1M | -$72.9M | -$68.0M | $8.7M | -$42.8M |
| Net Income | -$31.3M | -$67.1M | -$57.5M | $18.2M | -$24.2M |
| EBITDA | -$36.6M | -$58.3M | -$45.0M | $38.1M | $11.3M |
| EPS | $-1.24 | $-2.58 | $-2.14 | $0.66 | $-0.83 |
| EPS (Diluted) | — | — | — | — | — |
Balance Sheet (Annual)
Last updated: Jun 27, 2026 10:08am (just now)| Metric | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|
| Cash & Equivalents | $329.6M | $122.9M | $98.8M | $119.7M | $116.7M |
| Total Current Assets | $353.7M | $292.3M | $295.6M | $360.2M | $361.1M |
| Total Assets | $462.6M | $447.3M | $453.3M | $531.2M | $578.6M |
| Current Liabilities | $24.9M | $36.1M | $47.7M | $49.4M | $68.7M |
| Long-Term Debt | $0 | $0 | $0 | $9.7M | $9.6M |
| Total Liabilities | $50.8M | $48.2M | $62.1M | $75.4M | $107.7M |
| Total Equity | $411.7M | $399.2M | $391.3M | $455.8M | $470.9M |
| Retained Earnings | -$93.8M | -$160.9M | -$218.4M | -$200.1M | -$224.3M |
Cash Flow (Annual)
Last updated: Jun 27, 2026 10:08am (just now)| Metric | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|
| Operating Cash Flow | -$19.0M | -$41.7M | -$5.6M | $64.9M | $64.3M |
| Capital Expenditure | -$3.5M | -$5.6M | -$13.6M | -$28.3M | -$36.0M |
| Free Cash Flow | -$22.5M | -$47.3M | -$19.2M | $36.5M | $28.3M |
| Acquisitions (net) | -$63.2M | -$27.0M | $0 | $18,000 | -$18.7M |
| Debt Repayment | — | — | — | — | — |
| Dividends Paid | — | — | — | — | — |
| Stock Buybacks | $0 | $0 | $0 | $0 | $0 |
| Net Change in Cash | -$80.2M | -$206.7M | -$24.1M | $20.9M | -$3.0M |
Analyst Estimates (Annual)
Last updated: Jun 27, 2026 10:08am (just now)| Metric | 2027 | 2028 | 2029 | 2030 |
|---|---|---|---|---|
| Revenue |
$393.5M $390.4M – $397.3M
|
$435.1M $434.8M – $435.4M
|
$469.7M $466.0M – $474.2M
|
$507.9M $503.9M – $512.8M
|
| EBITDA |
-$68.6M -$69.3M – -$68.1M
|
-$75.9M -$75.9M – -$75.8M
|
-$81.9M -$82.7M – -$81.3M
|
-$88.6M -$89.4M – -$87.9M
|
| Net Income |
-$27.1M -$27.4M – -$26.8M
|
-$11.2M -$35.2M – $2.6M
|
$9.3M $9.2M – $9.4M
|
$21.4M $21.2M – $21.7M
|
| EPS | — | — | — | — |
Growth Trends (YoY %)
Last updated: Jun 27, 2026 10:08am (just now)| Metric | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|
| Revenue Growth | +45.7% | +60.4% | +51.1% | +3.7% |
| Gross Profit Growth | +34.2% | +66.4% | +55.5% | +0.5% |
| Operating Income Growth | -81.8% | +6.7% | +112.8% | -593.8% |
| Net Income Growth | -114.6% | +14.4% | +131.7% | -232.4% |
| EBITDA Growth | -59.4% | +22.8% | +184.7% | -70.3% |
Insider Trading (Recent)
Type codes
PPurchase
SSale
AAward / grant
MOption exercise
FIn-kind (tax)
CConversion
GGift
DReturn to issuer
All SEC Form 4 codes
Open market
- P Purchase
- Open-market or private purchase of shares.
- S Sale
- Open-market or private sale of shares.
Compensation (Rule 16b-3)
- A Award / grant
- Grant or award of securities (RSUs, options, etc.) under Rule 16b-3.
- D Return to issuer
- Securities disposed back to the company under Rule 16b-3.
- F In-kind (tax)
- Shares withheld or delivered to pay the option-exercise price or tax — not an open-market sale.
- I Discretionary
- Discretionary transaction under an employee plan — Rule 16b-3(f).
- M Option exercise
- Exercise or conversion of a derivative (option/RSU) into shares — exempt.
Derivatives
- C Conversion
- Conversion of a derivative security into the underlying shares.
- E Short expiration
- Expiration of a short derivative position.
- H Long expiration
- Expiration or cancellation of a long derivative position with value received.
- O OTM exercise
- Exercise of an out-of-the-money derivative.
- X ITM exercise
- Exercise of an in-the-money or at-the-money derivative.
Other exempt
- G Gift
- Bona fide gift of securities.
- L Small acquisition
- Small acquisition under Rule 16a-6.
- W Inheritance
- Acquisition or disposition by will or the laws of descent.
- Z Voting trust
- Deposit into or withdrawal from a voting trust.
Other
- J Other
- Other acquisition or disposition (explained in a Form 4 footnote).
- K Equity swap
- Transaction in an equity swap or similar instrument.
- U Tender / buyout
- Disposition via tender of shares in a change-of-control transaction.
Compensation-plan codes (A, D, F, M) are routine and rarely directional. Open-market P (buy) and S (sale) carry the most signal.
| Date | Insider | Type | Shares | Price | Value |
|---|---|---|---|---|---|
| 2026-06-16 | Oelschlager Kristen M | S-Sale | 8,587.00 | $20.71 | $177,837 |
| 2026-06-15 | MAETZOLD DEREK J | M-Exempt | 550.00 | $2.39 | $1,315 |
| 2026-06-15 | MAETZOLD DEREK J | S-Sale | 1,357.00 | $20.66 | $28,036 |
| 2026-06-15 | MAETZOLD DEREK J | S-Sale | 1,153.00 | $20.66 | $23,821 |
| 2026-06-15 | MAETZOLD DEREK J | M-Exempt | 550.00 | $2.39 | $1,315 |
| 2026-06-15 | MAETZOLD DEREK J | S-Sale | 550.00 | $20.66 | $11,363 |
| 2026-06-15 | MAETZOLD DEREK J | S-Sale | 278.00 | $20.66 | $5,743 |
| 2026-05-28 | Olson Tiffany | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-28 | Goldberg Ellen | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-28 | Harrison Miles | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-28 | Cotton Rodney | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-28 | Caple Kim | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-28 | BRADBURY DANIEL | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-28 | Cole G Bradley | A-Award | 11,766.00 | $0.00 | $0 |
| 2026-05-22 | Cole G Bradley | M-Exempt | 13,667.00 | $0.00 | $0 |
| 2026-05-22 | Cole G Bradley | M-Exempt | 13,667.00 | $0.00 | $0 |
| 2026-05-22 | BRADBURY DANIEL | M-Exempt | 13,667.00 | $0.00 | $0 |
| 2026-05-22 | BRADBURY DANIEL | M-Exempt | 13,667.00 | $0.00 | $0 |
| 2026-05-22 | Harrison Miles | M-Exempt | 13,667.00 | $0.00 | $0 |
| 2026-05-22 | Harrison Miles | M-Exempt | 13,667.00 | $0.00 | $0 |
Narrative Economics
The story the market is telling about this stock — the intangible X-factor
(founder mythology, cult dynamics, TAM-of-imagination) that moves price beyond
what cash flows alone explain. After Shiller, Narrative Economics.
No narrative profile yet for CSTL — it's generated by the pipeline (
market-narrative step).
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Data via Financial Modeling Prep · Cached for performance · fmp
v1.1.352 · d1100787 · 2026-06-26 11:39:30