CSTL Healthcare

Castle Biosciences, Inc.

$35.14+0.57%

Price as of close on Nov 3, 2026 · Financials updated Oct 8, 2026

Basics

Sector: Healthcare
Industry: Diagnostics & Research
Country: United States
Market cap: 1.1B USD
Enterprise value: 719.6M USD
Full-time employees: 1,002

Overall health

Strength: lower risk than most peers: more short-term liquidity and less debt relative to equitylower risk: more liquidity and less debt vs equity
Drawback: less profitable than most peersless profitable than peers
Drawback: its shares are priced higher than most peers relative to what it earnspriced higher than peers for its earnings
Drawback: its share price swings more than most peers’ (beta 0.94 vs a peer median of 0.63), though less than the overall marketbigger price swings (beta 0.94 vs peers 0.63)
About average: growth

Ranks #777 of 1,157 healthcare companies (bottom 33%)

See how it ranks against its peers

Worth knowing

Shareholders being diluted. Shares outstanding up 15% from December 2022 to July 2026.
Castle Biosciences had 15% more shares at July 2026 than at December 2022, mostly from issuing stock (for pay, acquisitions or fundraising). Each existing share now owns a smaller slice of the business.Castle Biosciences had 15% more shares at July 2026 than at December 2022, mostly from issuing stock. Each existing share now owns a smaller slice of the business.
Stock-based pay is a large cost. Stock pay was 13% of revenue in 2025.
Castle Biosciences paid employees $46M in stock in 2025, 13% of its $344M revenue. It doesn't use cash, so it flatters cash flow, but it is a real cost to shareholders through dilution.
Investment surge. Capital spending 10% of revenue, up from 4.1% in 2022.
Castle Biosciences is spending 10% of revenue on facilities and equipment, up from 4.1% in 2022. That weighs on free cash flow today; whether it pays off depends on the returns those investments earn.
Valuation signals disagree. Cheaper than 50% of peers on free cash flow, but only 0% on earnings.
Relative to its free cash flow, Castle Biosciences looks cheaper than 50% of peers; relative to its earnings, cheaper than only 0%. The valuation score blends the two, so look at which measure fits this business best.

StockQuotient Score

43/ 100

Oct 5 43 → Nov 4 43

Valuation

Is the price right?

8/100

Weak

3/3 inputs reported · High confidence

Since last quarter: No major changeValuation also moves with the share price every day.

Why

Weaker than most peers on:

▼ Earnings yield
▼ EBITDA yield

Compare with peers

Behind the score

Sector-normalized EBITDA, earnings, and free cash flow yields.

Earnings yield-1.8%

SEC filings · 12 months to Jun 2026Negative (a loss or cash outflow), so it counts as zero whatever the share price30% base weight · Z-score -1.00Sector median: 0.0148 · MAD: 0.0148

EBITDA yield-2.0%

SEC filings · 12 months to Jun 2026Negative (a loss or cash outflow), so it counts as zero whatever the share price50% base weight · Z-score -1.00Sector median: 0.0401 · MAD: 0.0401

Free cash flow yield-0.0%

SEC filings · 12 months to Jun 2026 · operating cash flow − capital spendingNegative (a loss or cash outflow), so it counts as zero whatever the share price20% base weight · Z-score 0.00Sector median: 0.0000 · MAD: 0.0000

Other data (not scored)

Book yield43.8%

SEC filings · latest balance sheetReported valueInformational · 0% composite weightSector median: 0.3716 · MAD: 0.2313

Growth

Is it growing?

57/100

Moderate

3/3 inputs reported · High confidence

Since last quarter: ▲ Stronger

12-month revenue up 5.1%

Why

Mixed versus peers:

▲ 3-yr revenue
▼ EPS growth

Compare with peers

Behind the score

Revenue and earnings-per-share growth over one year, and revenue growth over three years.

Earnings per share growthUnavailable

The loss per share widened33% base weight · Z-score -1.20Sector median: 0.0976 · MAD: 0.2991

3-year revenue growth28.7%

SEC filings · 3 years to Jun 2026Reported value33% base weight · Z-score 2.72Sector median: 0.0584 · MAD: 0.0840

Revenue growth3.2%

SEC filings · 12 months to Jun 2026Reported value33% base weight · Z-score -0.30Sector median: 0.0609 · MAD: 0.0974

Profitability

Does it earn well?

31/100

Weak

3/3 inputs reported · High confidence

Since last quarter: ▼ Weaker

Free cash flow turned negative over the last 12 months

Why

Weaker than most peers on:

▼ Operating margin
▼ ROIC
▼ ROA

Compare with peers

Behind the score

Return on invested capital, operating margin, and return on assets.

Operating margin-9.0%

SEC filings · 12 months to Jun 2026Reported value33% base weight · Z-score -1.32Sector median: 0.0706 · MAD: 0.1217

Return on assets-3.5%

SEC filings · 12 months to Jun 2026Reported value33% base weight · Z-score -0.95Sector median: 0.0166 · MAD: 0.0537

Return on invested capital-6.1%

SEC filings · 12 months to Jun 2026Reported value33% base weight · Z-score -1.07Sector median: 0.0471 · MAD: 0.1004

Other data (not scored)

Gross margin77.3%

SEC filings · 12 months to Jun 2026Reported valueInformational · 0% composite weightSector median: 0.4697 · MAD: 0.2310

Return on equity-4.1%

SEC filings · 12 months to Jun 2026Reported valueInformational · 0% composite weightSector median: 0.0330 · MAD: 0.1225

Risk

Debt, liquidity, price swings

Lower

Lower relative risk

3/3 inputs reported · High confidence

Since last quarter: No major change

Why

Stronger than most peers on:

▲ Debt / equity
▲ Current ratio

Compare with peers

Behind the score

Relative to sector peers: 0 = lower relative risk · 1 = moderate · 2 = higher. Based on leverage, beta and liquidity.

Beta0.94

Yahoo Finance · 5-year monthly beta vs the marketReported value33% base weight · Z-score -0.95Sector median: 0.6250 · MAD: 0.3380

Current ratio6.04×

SEC filings · latest balance sheetReported value33% base weight · Z-score 2.49Sector median: 2.5860 · MAD: 1.3850

Debt / equity0.02×

SEC filings · latest balance sheetReported value33% base weight · Z-score 0.98Sector median: 0.2215 · MAD: 0.2039

Valuation, growth and profitability scores: higher is better. Risk: 0 is lower, 2 is higher. Risk is a relative proxy, not a bankruptcy probability. Scores depend on available sector peers.

Questions investors ask about Castle Biosciences

Is Castle Biosciences getting weaker?: Its latest SEC filing (Jul 30, 2026) got weaker in some ways: free cash flow turned negative over the last 12 months. Its overall score is unchanged at 43/100 since Oct 28, 2026.
How is Castle Biosciences valued vs its peers?: Priced higher than most peers relative to what it earns. Valuation scores 8/100 against 1,393 healthcare peers. Earnings yield -1.8% vs a peer median of 1.5% (weaker than 100% of peers).Earnings yield -1.8% vs peers 1.5% (weaker than 100% of peers).
Is Castle Biosciences growing?: At about the same pace as its peers. Growth scores 57/100 against 1,393 healthcare peers. 3-year revenue growth 28.7% vs a peer median of 5.8% (stronger than 87% of peers).3-year revenue growth 28.7% vs peers 5.8% (stronger than 87% of peers).
How profitable is Castle Biosciences?: Less profitable than most of its peers. Profitability scores 31/100 against 1,393 healthcare peers. Operating margin -9.0% vs a peer median of 7.1% (weaker than 74% of peers).Operating margin -9.0% vs peers 7.1% (weaker than 74% of peers).
How risky is Castle Biosciences?: Lower risk relative to 1,393 healthcare peers, judged on debt, liquidity and share-price swings. Debt / equity 0.02× vs a peer median of 0.22× (stronger than 84% of peers).Debt / equity 0.02× vs peers 0.22× (stronger than 84% of peers). Beta 0.94 vs a peer median of 0.63 (weaker than 69% of peers).Beta 0.94 vs peers 0.63 (weaker than 69% of peers). A relative measure, not a bankruptcy probability.

Latest filing: what changed

Quarter ended Jun 30, 2026 · filed Jul 30, 2026 · compared with the quarter ended Mar 31, 2026

Got weaker

Free cash flow turned negative over the last 12 months

	Previous quarter	Latest quarter	Change
Revenue (12 months)	339.9M USD	357.3M USD	+5.1%
Net income (12 months)	−12.8M USD	−19.4M USD	+51.3%
Operating margin	-9.8%	-9.0%	+0.8 pts
Free cash flow (12 months)	4.5M USD	−489,000 USD	turned negative
Debt	10.1M USD	10.1M USD	+0.1%
Cash	63.8M USD	62.1M USD	−2.6%
Shares outstanding	30.3M	30.5M	+0.7%

From the company’s own SEC filings, as filed. Twelve-month figures roll forward one quarter at a time.

Industry valuation context

Industry: Diagnostics & Research · 26 companies

Valuations in Diagnostics & Research are within their usual range since Nov 2018.

53% of months since Nov 2018 were valued lower than now.
24% of companies are in the most expensive fifth of their own price-to-sales history.
Median price-to-sales is +109% vs the whole market, against a usual +111%.

Nov 2018Shaded: most expensive fifth of its range2026

Financials

Fiscal years from SEC annual filings · change vs the prior year

Key ratios	FY 2021	FY 2022	FY 2023	FY 2024	FY 2025	Change
Gross margin	—	—	—	—	—	—
Operating margin	-42.6%	-53.2%	-30.9%	2.6%	-12.4%	▼ 15 pts
Net margin	-33.3%	-49.0%	-26.1%	5.5%	-7.0%	▼ 13 pts
Return on assets (ROA)	-6.8%	-15.0%	-12.7%	3.4%	-4.2%	▼ 7.6 pts
Return on equity (ROE)	-7.6%	-16.8%	-14.7%	4.0%	-5.1%	▼ 9.1 pts
Free cash flow margin	-23.9%	-34.5%	-8.8%	11.0%	8.2%	▼ 2.8 pts
Current ratio	14.21×	8.09×	6.20×	7.29×	5.26×	▼ 28%
Quick ratio	14.13×	7.98×	6.04×	7.13×	5.11×	▼ 28%
Debt to equity	—	—	0.00×	0.02×	0.02×	▼ 2.9%
Interest coverage	-40079.00×	-4285.59×	-6179.73×	15.03×	-497.79×	▼ >999%

CSTL price history

Price history is added with the daily price update and will appear after the next one.

Similar companies

Sector leaderboards

BB Biotech AGBBZA.DE100/ 100

Arbutus Biopharma CorporationABUS97/ 100

Q32 Bio Inc.QTTB97/ 100

Bringing the fundamentals into focus…

Overall health

Strength: lower risk than most peers: more short-term liquidity and less debt relative to equitylower risk: more liquidity and less debt vs equity

Drawback: less profitable than most peersless profitable than peers

Drawback: its shares are priced higher than most peers relative to what it earnspriced higher than peers for its earnings

Drawback: its share price swings more than most peers’ (beta 0.94 vs a peer median of 0.63), though less than the overall marketbigger price swings (beta 0.94 vs peers 0.63)

About average: growth

Ranks #777 of 1,157 healthcare companies (bottom 33%)

See how it ranks against its peers

Worth knowing

Shareholders being diluted. Shares outstanding up 15% from December 2022 to July 2026.

Castle Biosciences had 15% more shares at July 2026 than at December 2022, mostly from issuing stock (for pay, acquisitions or fundraising). Each existing share now owns a smaller slice of the business.Castle Biosciences had 15% more shares at July 2026 than at December 2022, mostly from issuing stock. Each existing share now owns a smaller slice of the business.

Stock-based pay is a large cost. Stock pay was 13% of revenue in 2025.

Castle Biosciences paid employees $46M in stock in 2025, 13% of its $344M revenue. It doesn't use cash, so it flatters cash flow, but it is a real cost to shareholders through dilution.

Investment surge. Capital spending 10% of revenue, up from 4.1% in 2022.

Castle Biosciences is spending 10% of revenue on facilities and equipment, up from 4.1% in 2022. That weighs on free cash flow today; whether it pays off depends on the returns those investments earn.

Valuation signals disagree. Cheaper than 50% of peers on free cash flow, but only 0% on earnings.

Relative to its free cash flow, Castle Biosciences looks cheaper than 50% of peers; relative to its earnings, cheaper than only 0%. The valuation score blends the two, so look at which measure fits this business best.

Questions investors ask about Castle Biosciences

Is Castle Biosciences getting weaker?

Its latest SEC filing (Jul 30, 2026) got weaker in some ways: free cash flow turned negative over the last 12 months. Its overall score is unchanged at 43/100 since Oct 28, 2026.

How is Castle Biosciences valued vs its peers?

Priced higher than most peers relative to what it earns. Valuation scores 8/100 against 1,393 healthcare peers. Earnings yield -1.8% vs a peer median of 1.5% (weaker than 100% of peers).Earnings yield -1.8% vs peers 1.5% (weaker than 100% of peers).

Is Castle Biosciences growing?

At about the same pace as its peers. Growth scores 57/100 against 1,393 healthcare peers. 3-year revenue growth 28.7% vs a peer median of 5.8% (stronger than 87% of peers).3-year revenue growth 28.7% vs peers 5.8% (stronger than 87% of peers).

How profitable is Castle Biosciences?

Less profitable than most of its peers. Profitability scores 31/100 against 1,393 healthcare peers. Operating margin -9.0% vs a peer median of 7.1% (weaker than 74% of peers).Operating margin -9.0% vs peers 7.1% (weaker than 74% of peers).

How risky is Castle Biosciences?

Lower risk relative to 1,393 healthcare peers, judged on debt, liquidity and share-price swings. Debt / equity 0.02× vs a peer median of 0.22× (stronger than 84% of peers).Debt / equity 0.02× vs peers 0.22× (stronger than 84% of peers). Beta 0.94 vs a peer median of 0.63 (weaker than 69% of peers).Beta 0.94 vs peers 0.63 (weaker than 69% of peers). A relative measure, not a bankruptcy probability.

Previous quarter

Latest quarter

Change

Revenue (12 months)

339.9M USD

357.3M USD

+5.1%

Net income (12 months)

−12.8M USD

−19.4M USD

+51.3%

Operating margin

-9.8%

-9.0%

+0.8 pts

Free cash flow (12 months)

4.5M USD

−489,000 USD

turned negative

Debt

10.1M USD

10.1M USD

+0.1%

Cash

63.8M USD

62.1M USD

−2.6%

Shares outstanding

30.3M

30.5M

+0.7%

Key ratios

FY 2021

FY 2022

FY 2023

FY 2024

FY 2025

Change

Gross margin

—

Operating margin

-42.6%

-53.2%

-30.9%

2.6%

-12.4%

▼ 15 pts

Net margin

-33.3%

-49.0%

-26.1%

5.5%

-7.0%

▼ 13 pts

Return on assets (ROA)

-6.8%

-15.0%

-12.7%

3.4%

-4.2%

▼ 7.6 pts

Return on equity (ROE)

-7.6%

-16.8%

-14.7%

4.0%

-5.1%

▼ 9.1 pts

Free cash flow margin

-23.9%

-34.5%

-8.8%

11.0%

8.2%

▼ 2.8 pts

Current ratio

14.21×

8.09×

6.20×

7.29×

5.26×

▼ 28%

Quick ratio

14.13×

7.98×

6.04×

7.13×

5.11×

▼ 28%

Debt to equity

—

0.00×

0.02×

▼ 2.9%

Interest coverage

-40079.00×

-4285.59×

-6179.73×

15.03×

-497.79×

▼ >999%