MAETZOLD DEREK J

PrivateCIK: 1239501
Location

FRIENDSWOOD, TX

MAETZOLD DEREK J (Pres. & Chief Exec. Officer) sold 38.1% of their position (44.13K shares) of CASTLE BIOSCIENCES INC on the open market

Open‑market sale worth $1.13M — a major position exit. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 8 sales
InsiderMAETZOLD DEREK JCIK 1239501
IssuerCASTLE BIOSCIENCES INCCIK 1447362
DirectorOfficer10% Owner· Pres. & Chief Exec. Officer
Since Jul 2019
-44.13K
Net shares
Net seller
$1.13M
Total sold
8
Open market trades
0B · 8S
10
Total transactions
6.23K acquired · 50.35K disposed
Non-Derivative Transactions9

Common Stock

Direct
M · Option Exercise

Shares

+6.23K

Price / share

$2.39

Trade value

$14.88K

% of position

5.9%
3/11/2026
105.82K112.05K

Common Stock

Direct
S · Sale

Shares

17.31K

Price / share

$26.11

Trade value

$451.95K

% of position

15.4%
3/11/2026
112.05K94.74K

Common Stock

Indirect
S · Sale

Shares

1.36K

Price / share

$26.11

Trade value

$35.43K

% of position

2.6%
3/11/2026
52.92K51.57K

Common Stock

Indirect
S · Sale

Shares

1.16K

Price / share

$26.11

Trade value

$30.29K

% of position

2.6%
3/11/2026
44.99K43.83K

Common Stock

Indirect
S · Sale

Shares

282.00

Price / share

$26.11

Trade value

$7.36K

% of position

7.8%
3/11/2026
3.62K3.34K

Common Stock

Indirect
S · Sale

Shares

279.00

Price / share

$26.11

Trade value

$7.28K

% of position

7.7%
3/11/2026
3.62K3.34K

Common Stock

Indirect
S · Sale

Shares

279.00

Price / share

$26.11

Trade value

$7.28K

% of position

7.7%
3/11/2026
3.62K3.34K

Common Stock

Indirect
S · Sale

Shares

279.00

Price / share

$26.11

Trade value

$7.28K

% of position

7.7%
3/11/2026
3.62K3.34K

Common Stock

Direct
S · Sale

Shares

23.18K

Price / share

$25.28

Trade value

$585.94K

% of position

24.5%
3/12/2026
94.74K71.56K
Total

Net shares

37.90K

Net value

-$1.12M

Derivative Transactions1

Stock option (right to buy)

Direct
M · Option Exercise
Converts to

Common Stock

6.23K shares

Shares

6.23K

Strike price

2.39

Held after

14.28K

Exercisable

3/11/2026
Non-Derivative Holdings (Post-Transaction)3

Common Stock

Indirect
Shares owned44.32K

Common Stock

Indirect
Shares owned85.96K

Common Stock

Indirect
Shares owned18.72K
Total
149K indirect149K
Derivative Holdings (Post-Transaction)0
No derivative holdings reported
MAETZOLD DEREK J — Insider Transaction (Form 4) Filed Mar 13, 2026 | Finecho