StockCIK 1447362

CASTLE BIOSCIENCES INC (CSTL): Insider Trades and Fund Holdings

In the past 12 months, CASTLE BIOSCIENCES INC insiders reported 0 open-market purchases worth $0 and 25 sales worth $5.65M; 22 of the sales were reported as made under a 10b5-1 trading plan.

0Insider buys, 12 months

$0Bought by insiders, 12 months

$5.65MSold by insiders, 12 months

1Tracked funds holding

Recent insider trades

Open-market purchases (code P) and sales (code S) from Form 4. Grants, option exercises and gifts are not shown. Latest filing: Oct 21, 2026.

Recent CSTL insider trades
Filed	Traded	Insider	Role	Type	Shares	Price ($)	Value	Holding	Filing
Oct 21	Oct 19	Derek J. MaetzoldPres. & Chief Exec. Officer	Pres. & Chief Exec. Officer	▼ SELL10b5-1	8,580	31.91	$274K	−41%	Form 4 ↗
Oct 21	Oct 19	Derek J. MaetzoldPres. & Chief Exec. Officer	Pres. & Chief Exec. Officer (ind.)	▼ SELL10b5-1	5,916	31.91	$189K	−59%	Form 4 ↗
Oct 14	Oct 12	Tobin W. JuvenalChief Commercial Officer	Chief Commercial Officer	▼ SELL10b5-1	3,288	33.64	$111K	−6.3%	Form 4 ↗
Oct 7	Oct 5	Derek J. MaetzoldPres. & Chief Exec. Officer	Pres. & Chief Exec. Officer	▼ SELL10b5-1	8,580	35.57	$305K	−29%	Form 4 ↗
Oct 7	Oct 5	Derek J. MaetzoldPres. & Chief Exec. Officer	Pres. & Chief Exec. Officer (ind.)	▼ SELL10b5-1	5,916	35.57	$210K	−46%	Form 4 ↗
Oct 5	Oct 1	Kristen M. OelschlagerCOO	COO	▼ SELL10b5-1	4,153	35.95	$149K	−24%	Form 4 ↗
Oct 1	Sep 29	Tobin W. JuvenalChief Commercial Officer	Chief Commercial Officer	▼ SELL10b5-1	5,543	35.50	$197K	−9.5%	Form 4 ↗
Oct 1	Sep 30	Tobin W. JuvenalChief Commercial Officer	Chief Commercial Officer	▼ SELL10b5-1	1,034	34.20	$35K	−1.9%	Form 4 ↗
Sep 23	Sep 21	Derek J. MaetzoldPres. & Chief Exec. Officer	Pres. & Chief Exec. Officer	▼ SELL10b5-1	8,580	35.33	$303K	−29%	Form 4 ↗
Sep 23	Sep 21	Derek J. MaetzoldPres. & Chief Exec. Officer	Pres. & Chief Exec. Officer (ind.)	▼ SELL10b5-1	5,916	35.33	$209K	−38%	Form 4 ↗

Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings

All 25 CSTL insider trades →

Insiders who traded in the past year

Insider	Role	Bought	Sells	Sold	Latest
Derek J. Maetzold	Pres. & Chief Exec. Officer	$0	12	$2.79M	Oct 21, 2026
Tobin W. Juvenal	Chief Commercial Officer	$0	8	$990K	Oct 14, 2026
Kristen M. Oelschlager	COO	$0	4	$1.13M	Oct 5, 2026
Frank Stokes	CFO	$0	1	$742K	Aug 18, 2026

Tracked funds that report CSTL

From each fund's latest 13F. Holdings are as of quarter end and are filed up to 45 days later.

Fund	Quarter	Shares	Value	% of portfolio	Change
Renaissance Technologies	Q2 2026	371,200	$8.85M	0.01%	▼ −30.3%

Source: SEC Form 13F-HR filings, retrieved Oct 28, 2026. How we read filings

Reading these numbers

Insiders sell for many reasons: taxes, diversification, a house. Purchases with their own money are rarer and are usually read as more informative. A Form 4 is due within two business days of the trade. How to read a Form 4 →