Castle Biosciences, Inc.

CSTLNASDAQHealthcare● Active

$20.12

$-0.89(-4.24%)

Market Cap$610238634

P/E Ratio—

52W High$44.28

52W Low$14.59

Avg Volume383K

Open$20.94

Beta1.02

Insider Trades Ownership Employees

Castle Biosciences, Inc. (CSTL) Insider Trading

Form 4 buy vs sell counts, ratio, and sentiment — switch this quarter or last 12 months; chart and transactions below.

SEC EDGAR · FMP · CSTL · as of Jun 8, 2026

Activity summary

Buy transactions

P-Purchase only

Sell transactions

12 Months

Buy/Sell ratio

0.00

Buy/Sell (by trades)

Overall sentiment

BEARISH

↑ Buy 0%Active transactions only · RSU vesting excluded100% Sell ↓

Castle Biosciences, Inc. insiders have been primarily selling shares over the past 12 Months. Selling activity is often driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment toward the company.

▸ Source: SEC EDGAR · Form 3 & 4 · via Financial Modeling Prep · Buy = P-Purchase only · Sell = S-Sale only

As of Jun 8, 2026

CSTL insider buying and selling by quarter

CSTL insider selling · CSTL insider buying stocks · quarterly insider activity

Total insider buying (incl. awards)Total insider selling

581K290K0

2024 Q3

2024 Q4

2025 Q1

2025 Q2

2025 Q3

2025 Q4

2026 Q1

2026 Q2

Mobile shows last 4Q · Desktop shows full 8Q

▸ Source: SEC EDGAR · Form 3 & 4 · via Financial Modeling Prep · last 8 quarters

As of Jun 8, 2026

Active insiders

Most active in past 12 months · CSTL ceo insider trading

Showing all insiders · Click a card to filter the transactions table below

▸ Aggregated from reportingName · top 5 by trade count (12M) · no extra API

Recent insider transactions

CSTL executive sell shares · CSTL board member insider trading · CSTL insider trading SEC filing

Showing 68 most recent · Common Stock · Form 4 only

Scroll horizontally to see all columns

Date	Insider	Type	Shares	Price	Value	After trans.	Filing
May 22, 2026	Cole G Bradley Director	Option	13,667	—	—	32,976	Form 4
May 22, 2026	BRADBURY DANIEL Director	Option	13,667	—	—	22,340	Form 4
May 22, 2026	Harrison Miles Director	Option	13,667	—	—	35,631	Form 4
May 22, 2026	Olson Tiffany Director	Option	13,667	—	—	39,573	Form 4
May 22, 2026	Goldberg Ellen Director	Option	13,667	—	—	40,921	Form 4
May 22, 2026	Caple Kim Director	Option	13,667	—	—	36,121	Form 4
May 22, 2026	Cotton Rodney Director	Option	13,667	—	—	32,998	Form 4
May 21, 2026	Juvenal Tobin W Chief Commercial Officer	Option	11,210	$3.38	$38K	98,035	Form 4
May 20, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	322	$20.00	$6K	45,816	Form 4
May 21, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	1,035	$20.20	$21K	44,781	Form 4
May 20, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	273	$20.00	$5K	38,941	Form 4
May 21, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	880	$20.20	$18K	38,061	Form 4
May 21, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Option	420	$2.39	$1K	21,899	Form 4
May 20, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Option	130	$2.39	$311	21,609	Form 4
May 20, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	130	$20.00	$3K	21,479	Form 4
May 21, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	420	$20.20	$8K	21,479	Form 4
May 20, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	66	$20.00	$1K	2,158	Form 4
May 21, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	212	$20.20	$4K	1,946	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	1,159	$22.08	$26K	46,336	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	198	$22.59	$4K	46,138	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	985	$22.08	$22K	39,382	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	168	$22.59	$4K	39,214	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Option	6,214	$2.39	$15K	27,693	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	5,308	$22.08	$117K	22,385	Form 4
May 7, 2026	MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director	Sale	906	$22.59	$20K	21,479	Form 4

Cole G Bradley

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

BRADBURY DANIEL

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

Harrison Miles

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

Olson Tiffany

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

Goldberg Ellen

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

Caple Kim

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

Cotton Rodney

Director

Option

Date

May 22

13,667

Price

—

Value

—

View Form 4 on SEC.gov

Juvenal Tobin W

Chief Commercial Officer

Option

Date

May 21

11,210

Price

$3.38

Value

$38K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 20

322

Price

$20.00

Value

$6K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 21

1,035

Price

$20.20

Value

$21K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 20

273

Price

$20.00

Value

$5K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 21

880

Price

$20.20

Value

$18K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Option

Date

May 21

420

Price

$2.39

Value

$1K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Option

Date

May 20

130

Price

$2.39

Value

$311

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 20

130

Price

$20.00

Value

$3K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 21

420

Price

$20.20

Value

$8K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 20

Price

$20.00

Value

$1K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 21

212

Price

$20.20

Value

$4K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 7

1,159

Price

$22.08

Value

$26K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 7

198

Price

$22.59

Value

$4K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 7

985

Price

$22.08

Value

$22K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 7

168

Price

$22.59

Value

$4K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Option

Date

May 7

6,214

Price

$2.39

Value

$15K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 7

5,308

Price

$22.08

Value

$117K

View Form 4 on SEC.gov

MAETZOLD DEREK J

Pres. & Chief Exec. Officer · Director

Sale

Date

May 7

906

Price

$22.59

Value

$20K

View Form 4 on SEC.gov

⚡ = value ≥ $1M · Award/Option price shows — · formType=4 · securityName=Common Stock · url → sec.gov/Archives/edgar

1 / 3

▸ Source: SEC EDGAR · Form 4 filings · ⚡ = value ≥ $1M · Award/Option price shows —

About CSTL insider trading

CSTL insider trades

Castle Biosciences, Inc. (CSTL) insider trading data is sourced from SEC Form 4 filings submitted by corporate insiders, including MAETZOLD DEREK J (Pres. & Chief Exec. Officer · Director), Juvenal Tobin W (Chief Commercial Officer), Cole G Bradley (Director). Over the past 12 months, 5 insiders have filed transactions with the SEC. CSTL insiders have been primarily selling, which may reflect pre-scheduled Rule 10b5-1 plan executions.

For Castle Biosciences, Inc.'s institutional ownership breakdown and insider ownership percentage, see the Ownership tab → Ownership tab →

Buy/Sell signal logic

acquisitionOrDisposition field:

A = Acquisition (buy) · D = Disposition (sell)

RSU vesting (M-Exempt) excluded from sentiment

Form 4SEC filing required within 2 business days of any insider transaction

10b5-1Pre-scheduled trading plan that allows insiders to sell on autopilot

Open MktDirect purchase or sale on the open market (excludes awards, options)

Ownership SEC filings Financial statements Price history Forecast & ratings Earnings

Frequently asked questions

CSTL insider trading · 5 questions

The insiders of Castle Biosciences, Inc. (CSTL) include executives and directors such as MAETZOLD DEREK J (Pres. & Chief Exec. Officer · Director), Juvenal Tobin W (Chief Commercial Officer), Cole G Bradley (Director), among others. Over the past 12 months, 5 insiders have filed Form 4 transactions with the SEC. Insider transactions are required to be reported within 2 business days of the trade date.

CSTL board member insider tradingwho are CSTL insidersCSTL insider rosterCastle Biosciences, Inc. executives insider activity

▸ Source: FMP /stable/insider-trading/search · SEC EDGAR Form 3 & 4 · acquisitionOrDisposition A=Buy, D=Sell · RSU vesting (M-Exempt) excluded from sentiment bar · As of Jun 8, 2026