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Stock research / United States / CSTL · Services-Medical Laboratories · Nasdaq

Castle Biosciences Inc. (CSTL)

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Castle Biosciences Inc. (CSTL) reported revenue of $104 million for Q2 FY2026, the quarter ended 30 June 2026, up 20.1% on the same quarter a year earlier. Net income was -$2 million, and diluted earnings per share $-0.07. The figures are the company's own, from the 10-Q it filed with the SEC on 30 July 2026.

Revenue$104 millionup 20.1%
Net income-$2 million
Diluted EPS$-0.07
QuarterQ2 FY2026ended 30 June 2026

Castle Biosciences (CSTL) in brief

Castle Biosciences (CSTL) reported revenue of $344 million for fiscal 2025, the year ended 31 December 2025, up 3.7% on the year before.
Read moreNet loss was $24 million and the diluted loss per share $0.83. Revenue was $332 million in fiscal 2024, $220 million in fiscal 2023, $137 million in fiscal 2022 and $94 million in fiscal 2021. Net income in the same years was $18 million, a loss of $57 million, a loss of $67 million and a loss of $31 million. Over the twelve months to 30 June 2026, Castle Biosciences reported revenue of $357 million and net loss of $19 million. Revenue grew 40.6% a year, compounded, over the five years to fiscal 2025. Castle Biosciences had 31 million shares outstanding at the latest filed count. At 30 June 2026 it carried $10 million of debt and $62 million of cash. At the close of 29 October 2026 the market cap of Castle Biosciences was $1.2 billion.

Ratios

From the filings

ROE-4.1%
ROCE-6.7%
Operating margin-9.0%
Net margin-5.4%
FCF margin-0.1%
Interest cover-85.62
Debt to equity0.02
Cash conversionn/a
Share count, last 12 months5.3%
Sales CAGR, 3 years35.9%
Profit CAGR, 3 yearsn/a
EPS, TTM-$0.66

At the close of 29 October 2026

Price$38.51
Market cap$1.2 billion
Stock P/En/a
Price to book2.50
EV / EBITDAn/a
Dividend yield0.0%
Market cap / sales3.29
52-week high$43.04
52-week low$18.15
Price, 1 year62.2%
Price CAGR, 3 years39.4%
Price CAGR, 5 years-9.2%
Worked from the filed figures; hover a name for the formula.
Read moreThe priced ones use the latest price, the last regular-hours trade on IEX. Debt to equity here stands on long-term debt as Castle Biosciences Inc. files it, with lease liabilities counted separately and never inside it. Nothing here is a valuation or a view.
CSTLgreeksoup.ai
Daily prices to 29 October 2026, adjusted for splits; from 28 September 2026 each day's price is the last regular-hours trade on IEX.
Read moreData provided for free by IEX. By accessing or using IEX Historical Data, you agree to the IEX Historical Data Terms of Use. Day by day for the last three years; before that one point a week, carrying the week's last close and its average daily volume, so a volume bar means the same thing across the whole series; the bars sit under the price on their own scale, on the right. The moving averages need consecutive days and are drawn from the daily part. P/E is the close over the trailing four quarters' EPS as filed at each filing date, on the current share count; the dashed line is the median over the range shown. Sales and margin are quarterly revenue and the operating margin from the tables above. EV/EBITDA, price to book and market cap to sales use the latest filed balance sheet and share count at each date. Before the quarters on file begin, P/E, price to book and market cap to sales stand on each annual report from the day it was filed. Drawn in your browser; the range and overlay you pick are remembered here only.

The public record on CSTL

Dividendsno dividend in its filings for fiscal 2018 onward
Filings15 in twelve months: 6 current reports (8-K), about 5 results of operations; 5 regulation FD disclosure; 1 shareholder vote
Planned insider sales32 Form 144 notices in twelve months, $19.4 million; latest 13 October 2026
Options tapeput/call 0.18 by open interest at the 29 October 2026 close; the straddle prices a 15.6% move to 20 November 2026
13F holders176 funds reported a position for the quarter to 30 June 2026; largest BlackRock, Inc.
Insider trading217 sales and 0 purchases on Form 4 in twelve months
Congress0 House trades disclosed in six months
Short interest2.0 million shares short, 5.98 days to cover at 15 October 2026
Documentsthe 10-K, the 10-Qs, the proxy and 5 earnings press releases, each linked

Quarterly results, the last 20 quarters

Q3 FY2021Q4 FY2021 *Q1 FY2022Q2 FY2022Q3 FY2022Q4 FY2022 *Q1 FY2023Q2 FY2023Q3 FY2023Q4 FY2023 *Q1 FY2024 †Q2 FY2024Q3 FY2024Q4 FY2024 *Q1 FY2025Q2 FY2025Q3 FY2025Q4 FY2025 *Q1 FY2026Q2 FY2026
Revenue23.525.026.934.837.038.342.050.161.566.173.087.085.886.388.086.283.087.083.7104
Cost of revenue4.54.65.97.78.99.510.211.111.312.413.914.515.616.216.417.618.718.320.523.7
Gross profit19.020.420.927.228.228.831.939.150.253.759.172.570.270.171.668.664.368.763.179.8
Gross margin81%82%78%78%76%75%76%78%82%81%81%83%82%81%81%80%77%79%75%77%
R&D7.59.410.811.910.911.314.413.312.913.013.814.112.311.812.612.813.013.514.414.5
SG&A22.625.230.537.536.638.446.844.744.644.148.551.150.550.058.658.155.956.764.966.1
Operating income-11.8-15.2-24.5-4.0-21.5-22.8-31.5-21.2-9.6-5.7-5.55.05.14.0-27.9-4.3-6.8-3.8-18.4-3.1
Operating margin-50%-61%-91%-11%-58%-60%-75%-42%-16%-9%-7%6%6%5%-32%-5%-8%-4%-22%-3%
Interest expense0.00.00.00.00.00.00.00.00.00.00.00.20.20.10.00.00.00.00.10.2
Net income-11.8-6.4-24.6-1.6-20.2-20.6-29.2-18.8-6.9-2.6-2.58.92.39.6-25.84.5-0.5-2.3-14.5-2.1
Net margin-50%-26%-92%-5%-55%-54%-69%-37%-11%-4%-3%10%3%11%-29%5%-1%-3%-17%-2%
Diluted EPS-$0.47-$0.25-$0.97-$0.06-$0.77-$0.78-$1.10-$0.70-$0.26-$0.10-$0.09$0.31$0.08$0.32-$0.90$0.15-$0.02-$0.08-$0.49-$0.07
Operating cash flow-6.1-2.8-21.4-9.0-5.2-6.0-25.4-3.85.018.6-6.824.023.324.4-6.020.822.626.9-22.115.2
Capital expenditure0.90.90.41.42.01.83.34.02.53.89.25.26.47.64.79.314.87.212.58.7
Free cash flow-7.1-3.7-21.8-10.4-7.3-7.8-28.8-7.82.614.8-16.018.817.016.8-10.811.67.819.7-34.66.6
Shares outstanding25m25m25m26m26m27m27m27m27m27m28m28m28m28m29m29m29m30m30m31m
Filing10-Q10-K10-Q10-Q10-Q10-K10-Q10-Q10-Q10-K10-Q10-Q10-Q10-K10-Q10-Q10-Q10-K10-Q10-Q
Each quarter as filed, linked to its filing.
Read more* The fourth quarter is the full year less the first three quarters, because the company files the year and not the quarter on its own. A fourth quarter's EPS, and its diluted share count where shown, are from the company's results press release for that quarter, checked against the company's filed figures or a second data source. A quarter marked † is shown as the company last restated it in a later filing, so it compares with the quarters around it on one basis; rest on a figure for the one first filed. EPS is as filed. Money is in $ million as the company files it, or in $ billion by the switch above the tables; per share figures and the share count are as they are. Free cash flow is operating cash flow less capital expenditure; the effective tax rate is income tax over pre-tax income; margins are the line over revenue. Gross profit is revenue less cost of revenue, and operating income is revenue less the company's own total costs, where the statement does not print those lines. Cash flow lines filed year to date are the difference between two filings. Shares outstanding are at the period end where the balance sheet tags them, otherwise the count on the filing's cover page. A derived fourth-quarter EPS is left blank when a split in the year makes the arithmetic meaningless.

Income statement (profit and loss), 8 fiscal years and the trailing twelve months

FY2018 †FY2019FY2020FY2021FY2022FY2023FY2024FY2025TTM
Revenue22.851.962.694.1137220332344357
Cost of revenue5.37.39.715.832.045.060.271.081.3
Gross profit17.544.653.078.3105175272273276
Gross margin76.8%85.9%84.5%83.2%76.6%79.5%81.9%79.4%77.3%
Research and development4.97.413.329.644.953.652.051.955.4
Selling, general and administrative16.529.848.186.7143180200229244
Operating income-3.87.3-6.5-40.1-72.9-68.08.7-42.8-32.1
Operating margin-16.8%14.1%-10.4%-42.6%-53.2%-30.9%2.6%-12.4%-9.0%
Interest expense2.34.62.60.00.00.00.60.10.4
Income tax0.00.10.1-8.7-1.80.13.3-5.40.2
Net income-6.45.3-10.3-31.3-67.1-57.518.2-24.2-19.4
Net margin-27.9%10.2%-16.4%-33.3%-49.0%-26.1%5.5%-7.0%-5.4%
Diluted EPS-$5.33-$0.21-$0.54-$1.24-$2.58-$2.14$0.62-$0.83-$0.66
Filing10-K10-K10-K10-K10-K10-K10-K10-K
From each year's 10-K, linked; TTM is the last four quarters.
Read moreFree cash flow is operating cash flow less capital expenditure; the effective tax rate is income tax over pre-tax income; margins are the line over revenue. Gross profit is revenue less cost of revenue, and operating income is revenue less the company's own total costs, where the statement does not print those lines. Those four are arithmetic on the filed numbers; everything else is as filed. Money is in $ million as the company files it, or in $ billion by the switch above the tables; per share figures and share counts are as they are. † The year as the company last restated it in a later filing; rest on a figure for the one first filed. EPS is as filed.

Revenue by product or service FY2023 to FY2025

FY2023FY2024FY2025Share
of the parts, latest year
Dermatologic18325721662.9%
Non Dermatologic36.475.112837.1%
DermatologicNon Dermatologic
220FY2023332FY2024344FY2025

$ million; hover a block for its figure and share

From the company's 10-Ks, in its own words (latest 10-K).
Read moreEach year's figures come from the most recent 10-K that includes that year. A year is shown only where the parts add up to the revenue above. Fiscal years are labelled by the year they end in.

Cash flow and capital returned

FY2018 †FY2019FY2020FY2021FY2022FY2023FY2024FY2025TTM
Operating cash flow-12.37.09.9-19.0-41.7-5.664.964.342.6
Capital expenditure0.30.94.83.55.613.628.336.043.1
Free cash flow-12.66.15.1-22.5-47.3-19.236.528.3-0.5
Free cash flow margin-55.2%11.7%8.2%-23.9%-34.5%-8.8%11.0%8.2%-0.1%
Cash from investing-0.3-0.9-4.7-66.7-167-16.2-50.1-60.4-51.3
Cash from financing15.888.33065.41.5-2.36.1-7.0-11.4
Depreciation and amortisation0.30.40.53.410.512.316.040.815.6
Share-based compensation0.31.28.321.736.351.250.345.944.9
Dividend per share$0.00$0.00$0.00$0.00$0.00$0.00$0.00$0.00n/a
Diluted shares, weighted2m9m19m25m26m27m29m29m30m
Shares outstanding at period end2m17m25m25m27m27m28m30m31m
Filing10-K10-K10-K10-K10-K10-K10-K10-K
Cash paid in the year, from the cash flow statement.
Read moreThe dividend per share is as declared. Diluted shares are the weighted average for the year; a falling count is the buybacks net of issuance. TTM sums the last four quarters; the share counts are the latest quarter's.

Balance sheet at year end

FY2018 †FY2019FY2020FY2021FY2022FY2023FY2024FY2025TTM
Funded by
Shareholders' equity-56.685.1416412399391456471470
Short-term borrowings0.0n/an/an/an/an/an/an/an/a
Debt24.526.70.00.00.00.010.010.110.1
Operating lease liabilitiesn/an/a0.06.911.514.214.325.224.9
Finance lease liabilitiesn/an/an/a0.10.10.00.30.30.3
Other liabilities54.57.923.643.836.647.950.772.155.9
Total liabilities and equity22.4120439463447453531579561
Owned
Fixed assets1.52.17.19.514.3n/an/an/an/a
Goodwilln/an/an/a0.010.710.710.710.710.7
Intangible assets0.00.00.088.911610795.588.984.4
Investmentsn/an/an/a0.0136144173183205
Cash and equivalents4.598.841033012398.812011762.1
Receivables12.114.612.817.323.538.351.243.448.3
Inventory0.91.22.22.04.07.98.110.310.6
Other assets3.43.07.415.220.646.772.5126140
Total assets22.4120439463447453531579561
Filing10-K10-K10-K10-K10-K10-K10-K10-K
At the fiscal year end; the TTM column is the latest quarter end.
Read moreBoth totals are the company's own. Other liabilities is the filed total less the rows above it: payables, deferred revenue, taxes, borrowings the rows above do not carry and the rest; other assets is the same on the other side. Investments add the current and non-current lines as filed. Debt is the company's own stated total where it files one, otherwise its long-term debt with the current maturities, never parts added together. A row is left blank in a year where the lines shown overlap and the remainder would fall below nil.

Compounded growth

10 years5 years3 yearsTTM
Sales growth, compoundedn/a40.6%35.9%3.2%
Profit growth, compoundedn/an/an/an/a
Return on equity, averagen/a-8.0%-5.3%-5.1%
Yearly growth, compounded; TTM is the last four quarters against the four before.
Read moreReturn on equity is net income over shareholders' equity at each year end, averaged over the window (the TTM column is the latest year alone); equity is the parent's shareholders' equity as tagged in the 10-K. Arithmetic on filed numbers, nothing forecast.

Questions

What was Castle Biosciences' revenue in fiscal 2025?

Castle Biosciences (CSTL) reported revenue of $344 million for fiscal 2025, the year ended 31 December 2025, up 3.7% on the year before.

How much did Castle Biosciences earn in fiscal 2025?

Net loss was $24 million for fiscal 2025, and the diluted loss per share $0.83.

What is Castle Biosciences' market cap?

The market cap of Castle Biosciences was $1.2 billion at the close of 29 October 2026.

How much debt does Castle Biosciences have?

At 30 June 2026 Castle Biosciences carried $10 million of debt and $62 million of cash.

Peers: Healthcare

CompanyMarket capP/EROEOp. marginSales growth
TTM
Debt to equityDiv. yield
Natera, Inc. NTRA$62.6 billionn/a-10.6%-10.7%37.8%0.04n/a
Labcorp Holdings Inc. LH$29.8 billion30.4511.6%10.4%6.4%0.680.8%
Quest Diagnostics Inc. DGX$27.8 billion25.2014.8%14.6%9.1%0.731.3%
Guardant Health, Inc. GH$24.8 billionn/an/a-39.7%42.7%n/an/a
Caris Life Sciences, Inc. CAI$10.2 billion100.4417.8%15.5%n/a0.66n/a
Grail, Inc. GRAL$7.1 billionn/a-15.4%-338.4%23.1%0.00n/a
RadNet, Inc. RDNT$5.8 billionn/a-1.9%3.1%18.9%1.22n/a
Veracyte, Inc. VCYT$4.2 billion37.008.2%18.8%17.3%0.00n/a
CareDx, Inc. CDNA$3.8 billion29.9227.5%23.4%38.9%0.00n/a
Fortrea Holdings Inc. FTRE$2.2 billionn/a-12.9%0.5%-3.4%1.98n/a
Personalis, Inc. PSNL$1.7 billionn/a-45.6%-164.1%-13.3%n/an/a
Castle Biosciences Inc. CSTL$1.2 billionn/a-4.1%-9.0%3.2%0.020.0%
All 49 in Healthcare
CompanyMarket capP/EROEOp. marginSales growth
TTM
Debt to equityDiv. yield
HCA Healthcare, Inc. HCA$100.8 billion15.84n/a12.5%5.8%n/a0.6%
Natera, Inc. NTRA$62.6 billionn/a-10.6%-10.7%37.8%0.04n/a
Labcorp Holdings Inc. LH$29.8 billion30.4511.6%10.4%6.4%0.680.8%
Quest Diagnostics Inc. DGX$27.8 billion25.2014.8%14.6%9.1%0.731.3%
Guardant Health, Inc. GH$24.8 billionn/an/a-39.7%42.7%n/an/a
Tenet Healthcare Corp. THC$21.5 billion7.8553.3%24.4%6.2%2.40n/a
Encompass Health Corp. EHC$13.0 billion21.4123.9%18.0%9.5%1.010.6%
Davita Inc. DVA$12.3 billion14.24n/a15.0%6.4%n/an/a
BrightSpring Health Services, Inc. BTSG$11.9 billionn/an/an/an/a1.07n/a
Ensign Group, Inc. ENSG$10.9 billion27.7315.6%9.0%17.5%0.080.1%
Universal Health Services Inc. UHS$10.6 billion7.1920.3%11.4%10.0%0.650.5%
Caris Life Sciences, Inc. CAI$10.2 billion100.4417.8%15.5%n/a0.66n/a
Pacs Group, Inc. PACS$7.9 billion29.7124.2%7.4%16.6%0.22n/a
Grail, Inc. GRAL$7.1 billionn/a-15.4%-338.4%23.1%0.00n/a
Chemed Corp. CHE$7.0 billion25.9132.8%13.9%5.2%0.270.5%
Hims & Hers Health, Inc. HIMS$6.9 billionn/a-43.8%-6.0%28.0%4.21n/a
RadNet, Inc. RDNT$5.8 billionn/a-1.9%3.1%18.9%1.22n/a
Sotera Health Co. SHC$5.3 billion32.8224.6%n/a8.1%3.21n/a
Concentra Group Holdings Parent, Inc. CON$5.3 billion26.6041.7%16.4%14.0%3.300.6%
LifeStance Health Group, Inc. LFST$5.2 billion104.853.4%4.9%20.4%0.19n/a
Option Care Health, Inc. OPCH$4.8 billion23.9416.6%5.9%5.9%0.92n/a
Veracyte, Inc. VCYT$4.2 billion37.008.2%18.8%17.3%0.00n/a
CareDx, Inc. CDNA$3.8 billion29.9227.5%23.4%38.9%0.00n/a
National Healthcare Corp. NHC$3.3 billion23.7712.5%9.3%6.9%0.001.2%
Surgery Partners, Inc. SGRY$3.0 billionn/a-5.3%11.4%4.0%2.25n/a
Aveanna Healthcare Holdings, Inc. AVAH$2.9 billion10.7895.6%10.5%19.5%4.52n/a
Privia Health Group, Inc. PRVA$2.8 billion104.713.6%1.9%24.1%0.00n/a
Acadia Healthcare Company, Inc. ACHC$2.7 billionn/a-56.9%-32.6%4.3%1.22n/a
Brookdale Senior Living Inc. BKD$2.5 billionn/an/a3.5%-4.4%n/an/a
Addus HomeCare Corp. ADUS$2.3 billion21.799.2%10.0%15.9%0.05n/a
Pediatrix Medical Group, Inc. MD$2.3 billion15.8417.7%10.9%1.9%0.68n/a
Fortrea Holdings Inc. FTRE$2.2 billionn/a-12.9%0.5%-3.4%1.98n/a
Progyny, Inc. PGNY$2.2 billion30.8817.3%8.6%5.5%0.00n/a
GeneDx Holdings Corp. WGS$2.1 billionn/a-43.5%-20.3%25.4%0.41n/a
Ardent Health, Inc. ARDT$1.7 billion22.345.8%3.2%3.3%0.82n/a
Personalis, Inc. PSNL$1.7 billionn/a-45.6%-164.1%-13.3%n/an/a
Healthcare Services Group Inc. HCSG$1.7 billion16.5719.7%n/a4.0%0.00n/a
Sonida Senior Living, Inc. SNDA$1.6 billionn/a-14.2%-13.6%49.4%1.82n/a
Teladoc Health, Inc. TDOC$1.6 billionn/a-12.0%-6.6%-2.4%0.77n/a
Pennant Group, Inc. PNTG$1.5 billion47.188.0%5.6%37.9%0.49n/a
agilon health, Inc. AGL$1.4 billion26.42-102.1%-5.2%0.3%0.13n/a
U S Physical Therapy Inc. USPH$1.3 billion97.757.2%9.4%11.3%0.492.1%
InnovAge Holding Corp. INNV$1.3 billionn/a-1.1%0.3%15.9%0.21n/a
Omada Health, Inc. OMDA$1.2 billion393.201.7%-0.1%n/a0.00n/a
Castle Biosciences Inc. CSTL$1.2 billionn/a-4.1%-9.0%3.2%0.020.0%
AdaptHealth Corp. AHCO$808 millionn/a-16.6%-4.5%-0.4%1.37n/a
Starling Oncology, Inc. STLN$667 millionn/an/a-4.4%38.4%n/an/a
Fulgent Genetics, Inc. FLGT$596 millionn/a-8.4%-37.7%6.8%0.00n/a
SBC Medical Group Holdings Inc. SBC$583 million12.0918.6%37.3%-6.9%0.14n/a
12 companies share its SEC industry code (Services-Medical Laboratories); the rest are the names nearest in size in its wider industry, Healthcare, one of the Fama-French 48 industries, a published grouping of SEC industry codes.
Read moreBy market capitalisation; a click on a heading sorts by it, largest first, and a second click turns it round. Each figure is the same arithmetic as the ratio box above, on each company's own filings and latest close; a name marked * is a foreign company that files once a year, on its latest fiscal year.

Filings

FilingPeriodFiledWhere
10-Q30 June 202630 July 2026EDGAR
10-Q31 March 20266 May 2026EDGAR
10-K31 December 202526 February 2026EDGAR
10-Q30 September 20253 November 2025EDGAR
10-Q30 June 20254 August 2025EDGAR
10-Q31 March 20255 May 2025EDGAR
10-K31 December 202427 February 2025EDGAR
10-Q30 September 20244 November 2024EDGAR
10-Q30 June 20245 August 2024EDGAR
10-Q31 March 20242 May 2024EDGAR