CSTL

CASTLE BIOSCIENCES INC

Name: CASTLE BIOSCIENCES INC insider trading (SEC Form 4) history
Creator: U.S. Securities and Exchange Commission

SEC CIK 1447362

$20.70 −40.8% · 90 days

90-day buys

0 open-market

90-day sells

$865.3K

33 open-market

Net insider flow

−$865.3K

Net selling

Filings shown

Most recent

At a glance

Over the last 90 days, insiders at CSTL have sold a net $865.3K of stock (0 open-market buys vs 33 sells).

Largest recent trade: Juvenal Tobin W sold $526.6K of CSTL, trimming their stake 19%.

Most active filer: Maetzold Derek J, with 45 transactions among the recent filings shown.

Insider transaction history

Form 4 filings for CSTL, newest first

View on SEC EDGAR ↗

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed May 11, 2026 ΔOwn −0.4%

Maetzold Derek J sold $4.5K of CSTL.

−$4.5K

198 sh @ $23

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed May 11, 2026 ΔOwn −0.4%

Maetzold Derek J sold $3.8K of CSTL.

−$3.8K

168 sh @ $23

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed May 11, 2026 ΔOwn −1.8%

Maetzold Derek J sold $926 of CSTL, trimming their stake 2%.

−$926

41 sh @ $23

CSTL

CASTLE BIOSCIENCES INC

Option exercise MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Option exercise · filed Apr 23, 2026 ΔOwn +2.6%

+$1.3K

550 sh @ $2

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 23, 2026 ΔOwn −2.5%

Maetzold Derek J sold $13.8K of CSTL, trimming their stake 2%.

−$13.8K

550 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 23, 2026 ΔOwn −2.8%

Maetzold Derek J sold $34.1K of CSTL, trimming their stake 3%.

−$34.1K

1,357 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 23, 2026 ΔOwn −2.8%

Maetzold Derek J sold $28.9K of CSTL, trimming their stake 3%.

−$28.9K

1,153 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 23, 2026 ΔOwn −10%

Maetzold Derek J sold $7K of CSTL, trimming their stake 10%.

−$7K

278 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Option exercise MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Option exercise · filed Apr 8, 2026 ΔOwn +29%

+$14.9K

6,214 sh @ $2

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 8, 2026 ΔOwn −22%

Maetzold Derek J sold $155.5K of CSTL, trimming their stake 22%.

−$155.5K

6,214 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 8, 2026 ΔOwn −2.7%

Maetzold Derek J sold $34K of CSTL, trimming their stake 3%.

−$34K

1,357 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 8, 2026 ΔOwn −2.7%

Maetzold Derek J sold $28.9K of CSTL, trimming their stake 3%.

−$28.9K

1,153 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Apr 8, 2026 ΔOwn −9.1%

Maetzold Derek J sold $7K of CSTL, trimming their stake 9%.

−$7K

278 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Option exercise MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Option exercise · filed Mar 30, 2026 ΔOwn +2.6%

+$1.3K

550 sh @ $2

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 30, 2026 ΔOwn −2.5%

Maetzold Derek J sold $14.1K of CSTL, trimming their stake 2%.

−$14.1K

550 sh @ $26

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 30, 2026 ΔOwn −2.6%

Maetzold Derek J sold $34.7K of CSTL, trimming their stake 3%.

−$34.7K

1,357 sh @ $26

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 30, 2026 ΔOwn −2.6%

Maetzold Derek J sold $29.5K of CSTL, trimming their stake 3%.

−$29.5K

1,153 sh @ $26

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 30, 2026 ΔOwn −8.3%

Maetzold Derek J sold $7.1K of CSTL, trimming their stake 8%.

−$7.1K

278 sh @ $26

CSTL

CASTLE BIOSCIENCES INC

Option exercise Cotton Rodney · Director · Option exercise · filed Mar 30, 2026 ΔOwn +38%

+$0

5,329 sh

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 19, 2026 ΔOwn −2.9%

Maetzold Derek J sold $16.5K of CSTL, trimming their stake 3%.

−$16.5K

650 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 19, 2026 ΔOwn −46%

Maetzold Derek J sold $483.6K of CSTL, trimming their stake 46%.

−$483.6K

18,650 sh @ $26

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 17, 2026 ΔOwn −30%

Maetzold Derek J sold $453K of CSTL, trimming their stake 30%.

−$453K

17,449 sh @ $26

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 17, 2026 ΔOwn −0.3%

Maetzold Derek J sold $3.4K of CSTL.

−$3.4K

126 sh @ $27

CSTL

CASTLE BIOSCIENCES INC

Sell MAETZOLD DEREK J · Director, Pres. & Chief Exec. Officer · Open-market sale · filed Mar 17, 2026 ΔOwn −18%

Maetzold Derek J sold $336K of CSTL, trimming their stake 18%.

−$336K

13,204 sh @ $25

CSTL

CASTLE BIOSCIENCES INC

Sell Juvenal Tobin W · Chief Commercial Officer · Open-market sale · filed Mar 16, 2026 ΔOwn −19%

Juvenal Tobin W sold $526.6K of CSTL, trimming their stake 19%.

−$526.6K

20,863 sh @ $25

About CSTL insider activity

This page tracks every recent Form 4 filed for CASTLE BIOSCIENCES INC with the U.S. Securities and Exchange Commission. Form 4 is the disclosure that company insiders — officers, directors, and holders of more than 10% of the stock — must file within two business days of buying or selling shares.

The summary above nets open-market purchases against open-market sales over the trailing 90 days. Open-market trades (codes P and S) tend to carry the most signal because they reflect a deliberate choice to put money in or take it out, as opposed to routine grants, option exercises, or tax-withholding events. Use the badges on each row to tell them apart, and always confirm details against the original filing before drawing conclusions.

Frequently asked questions

How often is CSTL insider data updated?

Continuously. We read from SEC EDGAR, so new Form 4 filings for CASTLE BIOSCIENCES INC usually appear here within minutes of being accepted by the SEC.

What does "net insider flow" mean?

It is the total dollar value of open-market insider purchases minus open-market sales over the last 90 days. A positive number (green) means insiders bought more than they sold; a negative number (red) means the reverse.

Why do some rows show grants or option exercises instead of buys?

Insiders receive stock through compensation as well as buying it outright. Form 4 captures all of these. We label each transaction by its SEC code so you can focus on open-market activity if you prefer.

Is this investment advice?

No. InsiderSource presents public filing data for informational purposes only. Insider activity is one of many factors to consider and is never a recommendation to buy or sell.