Stocks · Healthcare · Medical - Diagnostics & Research
Castle Biosciences, Inc. CSTL
$36.65 +3.07% Close, Oct 5, 2026 · NASDAQ · Market cap $1.09B
Strong trendLow risk
Next earnings report: Nov 2, 2026
Scroll or pinch to zoom, drag to move. Daily prices adjusted for splits. Markers: E = earnings (green beat, red miss), S = split, D = dividend.
Three things to know
- The stock is in an uptrend: above its 200-day average for 33 trading days, with the 50-day average above the 200-day.
- Over the past year the stock returned +64.9%, ahead of the S&P 500 by 49.1 percentage points.
- The company holds net cash of $25.5M (cash above total debt).
PromtFinance scores
Each score is a percentile within the Healthcare sector (0–100). Under each score: how the stock ranks in its sector on every component. As of Oct 6, 2026.
How fast revenue, earnings and cash flow are growing.
- Revenue growth (TTM, YoY)Bottom 36%
- FCF growth (TTM, YoY)Bottom 13%
- Revenue growth, 3-year CAGRTop 18%
- Revenue growth accelerationTop 18%
Returns on capital, margins, earnings quality and balance-sheet strength.
- Return on invested capitalTop 39%
- Gross marginTop 34%
- Operating marginBottom 48%
- Accruals (lower is better)Top 31%
- Interest coverBottom 13%
How cheap the shares are relative to earnings, cash flow and their own history.
- Earnings yieldTop 35%
- Free-cash-flow yieldTop 36%
- EBITDA / enterprise valueTop 38%
- Sales / enterprise valueTop 39%
Strength and persistence of the price trend, including versus the S&P 500.
- 12-month return excluding last monthTop 34%
- 6-month returnTop 22%
- 1-year return vs S&P 500Top 23%
- Distance from 52-week highTop 29%
- Trend checklist (0–4)Top 10%
Earnings surprises and analyst sentiment (estimate-revision history is being collected).
- Average EPS surprise, last 4 quartersTop 11%
- Consecutive EPS beatsBottom 49%
- Share of analysts rating BuyTop 10%
- Upside to consensus price targetBottom 17%
Low volatility, shallow drawdowns, low market sensitivity and modest leverage.
- Volatility, 60 days (lower is better)Top 38%
- Maximum drawdown, 3 yearsTop 32%
- Beta vs S&P 500 (lower is better)Top 18%
What changed
Latest four quarters versus the same period a year earlier (growth: versus one quarter earlier).
| Measure | Before | Now | |
|---|---|---|---|
| Revenue growth (YoY) | -2.1% | 3.2% | ↑ |
| Gross margin | 81.0% | 77.3% | ↓ |
| Operating margin | -6.7% | -9.0% | ↓ |
| FCF margin | 10.0% | -0.1% | ↓ |
Fundamental momentum
| Measure | Now (TTM) | Year / quarter before | Sector rank | |
|---|---|---|---|---|
| Revenue growth (TTM, YoY) | 3.2% | -2.1% | ↑ | Bottom 36% |
| Gross margin | 77.3% | 81.0% | ↓ | Top 34% |
| Operating margin | -9.0% | -6.7% | ↓ | Bottom 48% |
| Net margin | -5.4% | -2.7% | ↓ | — |
| Free-cash-flow margin | -0.1% | 10.0% | ↓ | — |
| Return on invested capital | -6.3% | — | Top 39% | |
| Revenue growth, 3-year CAGR | 35.9% | — | Top 18% |
Quality of earnings and balance sheet
- Accruals (net income − OCF) / assetsLower is better; high accruals can signal weaker earnings quality.
- -11.1%
- Stock-based compensation / revenueA cost to shareholders through dilution.
- 12.6%
- Receivables growth vs revenue growthReceivables growing much faster than sales can be a warning.
- -10.8 pp
- Net debt / EBITDABelow 1× is conservative; above 3× is high leverage.
- Net cash
- Interest cover (operating income / interest)How many times operating profit covers interest.
- -85.6×
Shareholder returns
- Dividend yield (dividends paid, TTM)
- 0.00%
- Net buyback yield (TTM)
- -0.43%
- Shareholder yield
- -0.43%
- Share count change, 1 year
- +2.9%
- Share count change, 3-year CAGR
- +4.4%
Shareholder yield = dividends + net buybacks over the last four quarters, divided by market cap.
Based on the four quarters through Jun 30, 2026 (filed Jul 30, 2026).
Earnings and expectations
Earnings momentum
- Consecutive EPS beats
- 1
- Beats in the last 8 reports
- 6 of 8
- Average EPS surprise, last 4
- +60.5%
- Average 2-day reaction, last 8
- +1.9%
- Positive 20 days after report
- 3 of 8
Analysts
- Consensus price target
- $39.00
- Target vs current price
- +6.4%
- Analysts with a rating
- 11
- Share rating Buy or Strong Buy
- 100%
- Consensus rating
- Buy
How the stock reacted to recent reports
| Report date | EPS surprise | 2 days | 5 days | 20 days | 60 days |
|---|---|---|---|---|---|
| Jul 30, 2026 | +82.8% | +9.5% | +24.3% | +39.3% | — |
| May 6, 2026 | +0.0% | +0.6% | -24.3% | -17.1% | +13.8% |
| Feb 26, 2026 | +65.2% | +3.4% | -8.6% | -18.0% | -33.4% |
| Nov 3, 2025 | +94.1% | +1.9% | +29.6% | +53.4% | +53.6% |
| Aug 4, 2025 | +129.4% | +4.6% | +32.2% | +63.9% | +63.5% |
| May 5, 2025 | -1025.0% | -3.1% | -13.2% | -15.9% | -16.9% |
| Feb 27, 2025 | +900.0% | -2.9% | -18.1% | -22.9% | -39.0% |
| Nov 4, 2024 | +233.3% | +1.5% | +0.4% | -5.3% | -14.7% |
Returns from the close before each report. Past reactions do not determine future ones.
Earnings history
| Report date | EPS | Estimate | Surprise | Revenue |
|---|---|---|---|---|
| Jul 30, 2026 | -$0.07 | -$0.41 | +82.8% | $103.5M |
| May 6, 2026 | -$0.49 | -$0.49 | +0.0% | $84.2M |
| Feb 26, 2026 | -$0.08 | -$0.23 | +65.2% | $87.0M |
| Nov 3, 2025 | -$0.02 | -$0.34 | +94.1% | $83.0M |
| Aug 4, 2025 | $0.15 | -$0.51 | +129.4% | $86.2M |
| May 5, 2025 | -$0.90 | -$0.08 | -1025.0% | $87.2M |
| Feb 27, 2025 | $0.32 | -$0.04 | +900.0% | $86.3M |
| Nov 4, 2024 | $0.08 | -$0.06 | +233.3% | $85.8M |
Valuation in context
| Multiple | Now | 5-year median | 5-year percentile | Sector rank (cheapness) |
|---|---|---|---|---|
| EV / Sales | 2.97× | — | — | Top 39% |
| Free-cash-flow yield | -0.05% | — | — | Top 36% |
| Earnings yield | -1.79% | — | — | Top 35% |
Technical state
Trend checklist
- ✓ Price above 20-day average
- ✓ Price above 50-day average
- ✓ Price above 200-day average
- ✓ 50-day average above 200-day
- ✗ MACD histogram positive
Trend quality
- Days above the 50-day average
- 72
- Days above the 200-day average
- 33
- 50-day average slope (20 days)
- +15.0%
- 200-day average slope (20 days)
- -1.2%
- Distance from 50-day average
- +12.5%
- Distance from 200-day average
- +26.1%
- RSI (14)
- 64.7
- Relative volume
- 1.06×
Risk and drawdowns
- Volatility, 60 days (annualized)
- 49.0%
- Volatility vs own 5-year history
- 8th percentile · Low for this stock
- Beta vs S&P 500 (2 years, weekly)
- 0.54
- Correlation with S&P 500
- 0.13
- Current drawdown from 1-year high
- -14.8%
- Maximum drawdown, 3 years
- -57.8%
Largest declines in the past six years
| From peak | To low | Decline | Length | Recovery |
|---|---|---|---|---|
| Feb 9, 2021 | Jun 5, 2023 | -88.0% | 583 days | Not yet recovered |
| Oct 9, 2020 | Nov 25, 2020 | -20.5% | 33 days | 8 days (Dec 8, 2020) |
| Jan 20, 2021 | Jan 27, 2021 | -20.5% | 5 days | 5 days (Feb 3, 2021) |
Declines of 10% or more from a closing high, measured on daily closes.
Financial statements
- Market cap
- $1.09B
- EPS, diluted (TTM)
- -$0.66
- Revenue (TTM)
- $357.3M
- 52-week range
- $17.72 – $44.28
| FY 2021 | FY 2022 | FY 2023 | FY 2024 | FY 2025 | |
|---|---|---|---|---|---|
| Revenue | $94.1M | $137.0M | $219.8M | $332.1M | $344.2M |
| Gross profit | $78.3M | $105.0M | $174.8M | $271.9M | $273.2M |
| Operating income | -$40.1M | -$72.9M | -$68.0M | $8.7M | -$42.8M |
| Net income | -$31.3M | -$67.1M | -$57.5M | $18.2M | -$24.2M |
| EPS (diluted) | -$1.24 | -$2.58 | -$2.14 | $0.62 | -$0.83 |
| Q3 2024 | Q4 2024 | Q1 2025 | Q2 2025 | Q3 2025 | Q4 2025 | Q1 2026 | Q2 2026 | |
|---|---|---|---|---|---|---|---|---|
| Revenue | $85.8M | $86.3M | $88.0M | $86.2M | $83.0M | $87.0M | $83.7M | $103.5M |
| Net income | $2.3M | $9.6M | -$25.8M | $4.5M | -$501,000 | -$2.3M | -$14.5M | -$2.1M |
| EPS (diluted) | $0.08 | $0.32 | -$0.90 | $0.15 | -$0.02 | -$0.08 | -$0.49 | -$0.07 |
| FY 2021 | FY 2022 | FY 2023 | FY 2024 | FY 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 |
| Dividends paid | $0 | $0 | $0 | $0 | $0 |
| Net share buybacks | $0 | $0 | $0 | $2.0M | $2.2M |
Cash outflows are shown as negative numbers.
- Cash and short-term investments
- $266.8M
- Total assets
- $561.2M
- Total liabilities
- $91.1M
- Total debt
- $36.6M
- Net debt
- -$25.5M
- Shareholders’ equity
- $470.0M
As of Jun 30, 2026 (filed Jul 30, 2026).
Short interest
- Shares sold short
- 1,899,369
- Days to cover
- 7.36
- Change vs previous report
- -3.9%
FINRA short interest, settlement date Sep 15, 2026.