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NASDAQ: CSTL
Castle Biosciences Inc Stock Ownership - Who owns Castle Biosciences?

OverviewForecastEarningsRevenueDividendOwnership

Insider buying vs selling

Have Castle Biosciences Inc insiders been buying or selling?

Buy
Sell
NameRoleDateSharesPriceValue
Derek J. MaetzoldCEO;Pres2026-08-05473$30.68
$14.51kSell
Derek J. MaetzoldCEO;Pres2026-08-05556$30.68
$17.06kSell
Derek J. MaetzoldCEO;Pres2026-08-052,546$30.68
$78.11kSell
Derek J. MaetzoldCEO;Pres2026-08-052,546$2.39
$6.08kBuy
Derek J. MaetzoldCEO;Pres2026-08-0420,356$2.39
$48.65kBuy
Derek J. MaetzoldCEO;Pres2026-08-044,063$31.34
$127.32kSell
Derek J. MaetzoldCEO;Pres2026-08-043,374$30.79
$103.88kSell
Derek J. MaetzoldCEO;Pres2026-08-048,421$30.79
$259.27kSell
Derek J. MaetzoldCEO;Pres2026-08-044,782$31.34
$149.85kSell
Derek J. MaetzoldCEO;Pres2026-08-0411,935$31.34
$374.00kSell

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Net Insider Buy/Sell (L12M) Ownership

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CSTL Shareholders

What type of owners hold Castle Biosciences Inc stock?

Institutional
Insider
Retail
NameHoldSharesValueType
Blackrock Inc9.76%2,982,946$95.54MInstitution
Rtw Investments LP9.03%2,758,335$88.35MInstitution
Principal Financial Group Inc5.79%1,769,877$56.69MInstitution
Sofinnova Healthquest Partners LP4.69%1,433,577$45.92MInsider
Portolan Capital Management LLC4.42%1,350,283$43.25MInstitution
Vanguard Capital Management LLC3.85%1,177,522$37.72MInstitution
Dimensional Fund Advisors LP3.40%1,039,761$33.30MInstitution
Derek J. Maetzold3.19%974,183$31.20MInsider
Summit Partners Public Asset Management LLC3.08%940,685$30.13MInstitution
Vanguard Portfolio Management LLC2.82%861,771$27.60MInstitution

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CSTL vs Diagnostic & Research Stocks

TickerInst. %Insider %Net Insider (L12M)Net Insider (L3M)
CSTL85.32%14.68%Net SellingNet Selling
OPK20.76%79.24%Net BuyingNet Selling
ACRS58.09%41.91%Net SellingNet Selling
FRNM9.46%24.63%Net BuyingNet Buying
FLGT56.66%43.34%Net SellingNet Selling
View Top Diagnostic & Research Stocks

Castle Biosciences Stock Ownership FAQ

Who owns Castle Biosciences?

Castle Biosciences (NASDAQ: CSTL) is owned by 90.38% institutional shareholders, 15.55% Castle Biosciences insiders, and 0.00% retail investors. Sofinnova Healthquest Partners LP is the largest individual Castle Biosciences shareholder, owning 1.43M shares representing 4.69% of the company. Sofinnova Healthquest Partners LP's Castle Biosciences shares are currently valued at $45.92M.

If you're new to stock investing, here's how to buy Castle Biosciences stock.
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