Castle Biosciences Ownership

Who are the major shareholders and have insiders been buying or selling?

Recent Insider Transactions

Insider Trading Volume

Insider Buying: Insufficient data to determine if insiders have bought more shares than they have sold in the past 3 months.

Ownership Breakdown

What is the ownership structure of CSTL?
Owner Type	Number of Shares	Ownership Percentage
Individual Insiders	759,135	2.62%
Hedge Funds	1,489,572	5.13%
General Public	1,615,663	5.57%
Institutions	25,143,911	86.7%

Dilution of Shares: Shareholders have not been meaningfully diluted in the past year.

Top Shareholders

Top 25 shareholders own 73.82% of the company

Ownership	Name	Shares	Current Value	Change %	Portfolio %
10.9%	BlackRock, Inc.	3,154,679	US$71.7m	5.74%	no data
7.48%	The Vanguard Group, Inc.	2,170,028	US$49.3m	5.98%	no data
6.2%	Principal Global Investors, LLC	1,799,050	US$40.9m	22.6%	0.02%
5.13%	Portolan Capital Management, LLC	1,489,572	US$33.8m	17.7%	1.74%
4.75%	Dimensional Fund Advisors LP	1,378,005	US$31.3m	14.8%	no data
3.62%	Wasatch Advisors LP	1,049,773	US$23.9m	5.14%	0.08%
3.06%	Citadel Advisors LLC	888,515	US$20.2m	244%	0.02%
2.84%	Braidwell LP	822,735	US$18.7m	125%	0.75%
2.66%	Teachers Insurance and Annuity Association-College Retirement Equities Fund	772,054	US$17.5m	6.7%	no data
2.46%	Allianz Asset Management GmbH	712,242	US$16.2m	11.5%	0.01%
2.44%	State Street Global Advisors, Inc.	707,687	US$16.1m	-1.03%	no data
2.38%	Geode Capital Management, LLC	689,926	US$15.7m	6.17%	no data
2.31%	Renaissance Technologies LLC	670,500	US$15.2m	-4.38%	0.02%
2.24%	Schroder Investment Management North America Inc.	648,572	US$14.7m	8.62%	0.04%
1.98%	Palisade Capital Management, LP	575,116	US$13.1m	17.4%	0.4%
1.88%	Acadian Asset Management LLC	544,250	US$12.4m	-19.5%	0.02%
1.61%	UBS Asset Management AG	466,590	US$10.6m	300%	no data
1.48%	Millennium Management LLC	428,397	US$9.7m	68.2%	0.01%
1.4%	Wellington Management Group LLP	407,211	US$9.3m	-50.9%	no data
1.28%	Columbia Management Investment Advisers, LLC	372,467	US$8.5m	14.4%	no data
1.27%	Bank of America Corporation	369,248	US$8.4m	0.44%	no data
1.21%	Parkman Healthcare Partners LLC	352,262	US$8.0m	0.49%	0.78%
1.13%	Derek Maetzold	327,038	US$7.4m	-1.21%	no data
1.1%	Trexquant Investment LP	318,072	US$7.2m	27.7%	0.08%
1.04%	Nuveen Investments, Inc.	301,053	US$6.8m	47.8%	0.02%

Company Analysis and Financial Data Status

Data	Last Updated (UTC time)
Company Analysis	2025/10/05 04:27
End of Day Share Price	2025/10/03 00:00
Earnings	2025/06/30
Annual Earnings	2024/12/31

Data Sources

The data used in our company analysis is from S&P Global Market Intelligence LLC. The following data is used in our analysis model to generate this report. Data is normalised which can introduce a delay from the source being available.

Package	Data	Timeframe	Example US Source ^*
Company Financials	10 years	Income statement Cash flow statement Balance sheet	SEC Form 10-K SEC Form 10-Q
Analyst Consensus Estimates	+3 years	Forecast financials Analyst price targets	Analyst Research Reports Blue Matrix
Market Prices	30 years	Stock prices Dividends, Splits and Actions	ICE Market Data SEC Form S-1
Ownership	10 years	Top shareholders Insider trading	SEC Form 4 SEC Form 13D
Management	10 years	Leadership team Board of directors	SEC Form 10-K SEC Form DEF 14A
Key Developments	10 years	Company announcements	SEC Form 8-K

^* Example for US securities, for non-US equivalent regulatory forms and sources are used.

Unless specified all financial data is based on a yearly period but updated quarterly. This is known as Trailing Twelve Month (TTM) or Last Twelve Month (LTM) Data. Learn more.

Analysis Model and Snowflake

Details of the analysis model used to generate this report is available on our Github page, we also have guides on how to use our reports and tutorials on Youtube.

Learn about the world class team who designed and built the Simply Wall St analysis model.

Industry and Sector Metrics

Our industry and section metrics are calculated every 6 hours by Simply Wall St, details of our process are available on Github.

Analyst Sources

Castle Biosciences, Inc. is covered by 9 analysts. 8 of those analysts submitted the estimates of revenue or earnings used as inputs to our report. Analysts submissions are updated throughout the day.

Analyst	Institution
Catherine Ramsey Schulte	Baird
Mark Massaro	BTIG
Kyle Mikson	Canaccord Genuity