# Castle Biosciences, Inc. (CSTL)

> Source: Nexqual · https://nexqual.com/CSTL · data as of 2026-10-23 16:26 UTC · cite as "Nexqual, Castle Biosciences, Inc. (CSTL), nexqual.com/CSTL" · informational, not investment advice.

**Price:** USD 33.09 (-0.32% today) · US market open, as of October 23, 2026 at 16:26 UTC; quotes may be delayed. Prev close 33.19 · day 32.69–33.61 · 52w 17.72–44.28 · market cap $1.01B · NGM

## Key facts
- Last four reported quarters (through Jun 30, 2026): revenue $357M, net income -$19.4M (-5.4% margin), free cash flow -$489K (SEC filings).
- Analysts: Buy (mean 2.00 on a 1–5 scale) (9 analysts), mean target USD 45.22 (range 35–57).
- Total return with dividends: 1Y +36.8% vs S&P 500 +14.6%; 5Y -46.9% vs S&P 500 +77.3%.
- Next earnings: 2026-11-05, EPS estimate USD -0.35, revenue estimate $92.5M.

## Financials (SEC 10-K; TTM = last four 10-Q/10-K quarters)
| USD | FY2021 | FY2022 | FY2023 | FY2024 | FY2025 | TTM |
|---|---|---|---|---|---|---|
| Revenue | $94.1M | $137M | $220M | $332M | $344M | $357M |
| Gross profit | $78.3M | $105M | $175M | $272M | $273M | — |
| Operating income | -$40.1M | -$72.9M | -$68.0M | $8.7M | -$42.8M | -$32.1M |
| Net income | -$31.3M | -$67.1M | -$57.5M | $18.2M | -$24.2M | -$19.4M |
| EPS (diluted) | -$1.24 | -$2.58 | -$2.14 | $0.62 | -$0.83 | — |
| Free cash flow | -$22.5M | -$47.3M | -$19.2M | $36.5M | $28.3M | -$489K |
| Gross margin | 83.2% | 76.6% | 79.5% | 81.9% | 79.4% | — |
| Operating margin | -42.6% | -53.2% | -30.9% | 2.6% | -12.4% | -9.0% |
| Net margin | -33.3% | -49.0% | -26.1% | 5.5% | -7.0% | -5.4% |
| Revenue growth | +50.2% | +45.7% | +60.4% | +51.1% | +3.7% | — |
| Cash + short-term investments | $330M | $259M | $243M | $293M | $300M | — |
| Total debt | — | — | $0K | $10.0M | $10.1M | — |
Fiscal years end Dec. EPS is split-adjusted.

## Valuation (price ÷ last four quarters, through Jun 30, 2026)
P/S 2.8x · EV/Sales 2.1x · P/B 2.1x · FCF yield -0.05% · Earnings yield -1.92% · Net cash $257M · EV $754M
P/E at fiscal year-ends: Dec 2024 42.7x.

## Analysts
Consensus Buy (mean 2.00 on a 1–5 scale), 9 analysts; mean target USD 45.22 (low 35, high 57).
Rating changes, last 120 days:
| Date | Firm | Action | Rating | Price target |
|---|---|---|---|---|
| 2026-08-03 | BTIG | Target raised | Buy | $40 → $44 |

## Total return (dividends reinvested)
|  | 1Y (from 2025-10-23) | 5Y (from 2021-10-25) |
|---|---|---|
| Total return | +36.8% | -46.9% |
| S&P 500 (SPY) | +14.6% | +77.3% |
| Per year | +36.9% | -11.9% |
| Volatility (annualized) | 57.7% | 71.7% |
| Max drawdown | -57.8% (Jan 2026→May 2026) | -80.1% (Oct 2021→Oct 2023) |

## Peers (Diagnostics & Research)
OPK (Opko Health, Inc.) USD 1.62 -0.49% · FRNM (Freenome, Inc.) USD 12.62 -3.66% · PSNL (Personalis, Inc.) USD 15.83 +0.06% · MYGN (Myriad Genetics, Inc.) USD 5.82 +0.95% · FLGT (Fulgent Genetics, Inc.) USD 20.09 +0.48% · WGS (GeneDx Holdings Corp.) USD 60.14 -10.43%

## More
Full page: https://nexqual.com/CSTL · Free keyless MCP server with the same data and citations: https://mcp.nexqual.com/mcp · Guide for agents: https://nexqual.com/agents · https://nexqual.com/llms.txt

## Supply chain and relationships (SEC annual reports)

Named in CSTL's own 10-K filed 2026-02-26 (https://www.sec.gov/Archives/edgar/data/1447362/000162828026012272/cstl-20251231.htm):

| Relationship | Company | Sentence in the filing |
|---|---|---|
| Supplier | ThermoFisher Scientific | "We procure certain reagents, equipment, chips/cards and other materials used to perform our tests from sole suppliers such as ThermoFisher Scientific, Inc., Promega and Qiagen, Inc. Some of these items are unique to thes…" |
| Supplier | Promega and Qiagen | "We procure certain reagents, equipment, chips/cards and other materials used to perform our tests from sole suppliers such as ThermoFisher Scientific, Inc., Promega and Qiagen, Inc. Some of these items are unique to thes…" |
| Supplier | General | "General business and economic conditions that could affect our business, financial condition or results of operations include fluctuations in economic growth, debt and equity capital markets, liquidity of the global fina…" |

## Revenue by product line (quarter ended 2026-06-30)

| Line | Revenue | Share | YoY |
|---|---|---|---|
| Non-Dermatologic | $54.8M | 53.0% | +83.5% |
| Dermatologic | $48.7M | 47.0% | -13.5% |
| Total revenue | $103.5M | 100% | — |

## Company outlook (8-K filed 2026-07-30)

- "Castle Biosciences is raising its guidance for anticipated total revenue i n 2026."
- "The Company now anticipates generating between $365-375 million in total revenue in 2026, compared to the previously provided guidance of between $345-355 million."
- "Further, the Company expects to achieve positive Adjusted EBITDA for the third quarter, the fourth quarter and the full year 2026."

## Analyst estimates and revisions

| Period | EPS est. | 90d ago | Change | Revenue est. | Analysts |
|---|---|---|---|---|---|
| Current quarter (ends 2026-09-30) | $-0.35 | $-0.30 | +16.2% | $92.5M | 9 |
| Next quarter (ends 2026-12-31) | $-0.36 | $-0.29 | +24.9% | $94.2M | 9 |
| Current fiscal year (ends 2026-12-31) | $-1.26 | $-1.42 | -11.2% | $373.5M | 9 |
| Next fiscal year (ends 2027-12-31) | $-0.91 | $-0.96 | -4.5% | $412.5M | 9 |

## Options: expected move (Cboe, 15-min delayed)

Expected move by 2027-01-15 (includes earnings 2026-11-05): ±21.8%; last 8 reports averaged ±17.1%.

| Expiration | Days | ATM IV | Expected move |
|---|---|---|---|
| 2027-01-15 | 84 | 54.7% | ±21.8% |
| 2027-04-16 | 175 | 59.1% | ±33.4% |