MAETZOLD DEREK J

PrivateCIK: 1239501
Location

FRIENDSWOOD, TX

MAETZOLD DEREK J (Pres. & Chief Exec. Officer) sold 66.6% of their position (39.02K shares) of CASTLE BIOSCIENCES INC on the open market

Open‑market sale worth $1.21M — a major position exit. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 9 sales
InsiderMAETZOLD DEREK JCIK 1239501
IssuerCASTLE BIOSCIENCES INCCIK 1447362
DirectorOfficer10% Owner· Pres. & Chief Exec. Officer
Since Jul 2019
-39.02K
Net shares
Net seller
$1.21M
Total sold
9
Open market trades
0B · 9S
13
Total transactions
22.90K acquired · 61.92K disposed
Non-Derivative Transactions11

Common Stock

Direct
M · Option Exercise

Shares

+20.36K

Price / share

$2.39

Trade value

$48.65K

% of position

94.8%
8/4/2026
21.48K41.84K

Common Stock

Direct
S · Sale

Shares

8.42K

Price / share

$30.79

Trade value

$259.27K

% of position

20.1%
8/4/2026
41.84K33.41K

Common Stock

Indirect
S · Sale

Shares

3.37K

Price / share

$30.79

Trade value

$103.88K

% of position

10.6%
8/4/2026
31.78K28.41K

Common Stock

Indirect
S · Sale

Shares

2.87K

Price / share

$30.79

Trade value

$88.24K

% of position

10.6%
8/4/2026
27.01K24.14K

Common Stock

Direct
S · Sale

Shares

11.94K

Price / share

$31.34

Trade value

$374K

% of position

35.7%
8/4/2026
33.41K21.48K

Common Stock

Indirect
S · Sale

Shares

4.78K

Price / share

$31.34

Trade value

$149.85K

% of position

16.8%
8/4/2026
28.41K23.63K

Common Stock

Indirect
S · Sale

Shares

4.06K

Price / share

$31.34

Trade value

$127.32K

% of position

16.8%
8/4/2026
24.14K20.08K

Common Stock

Direct
M · Option Exercise

Shares

+2.55K

Price / share

$2.39

Trade value

$6.08K

% of position

11.9%
8/5/2026
21.48K24.02K

Common Stock

Direct
S · Sale

Shares

2.55K

Price / share

$30.68

Trade value

$78.11K

% of position

10.6%
8/5/2026
24.02K21.48K

Common Stock

Indirect
S · Sale

Shares

556.00

Price / share

$30.68

Trade value

$17.06K

% of position

2.4%
8/5/2026
23.63K23.07K

Common Stock

Indirect
S · Sale

Shares

473.00

Price / share

$30.68

Trade value

$14.51K

% of position

2.4%
8/5/2026
20.08K19.61K
Total

Net shares

16.11K

Net value

-$1.16M

Derivative Transactions2

Stock option (right to buy)

Direct
M · Option Exercise
Converts to

Common Stock

20.36K shares

Shares

20.36K

Strike price

2.39

Held after

41.40K

Exercisable

8/4/2026

Stock option (right to buy)

Direct
M · Option Exercise
Converts to

Common Stock

2.55K shares

Shares

2.55K

Strike price

2.39

Held after

38.86K

Exercisable

8/5/2026
Non-Derivative Holdings (Post-Transaction)8

Common Stock

Indirect
Shares owned11.81K

Common Stock

Indirect
Shares owned27.86K

Common Stock

Indirect
Shares owned23.22K

Common Stock

Indirect
Shares owned40.94K

Common Stock

Indirect
Shares owned11.81K

Common Stock

Indirect
Shares owned11.96K

Common Stock

Indirect
Shares owned11.81K

Common Stock

Indirect
Shares owned11.81K
Total
151.22K indirect151.22K
Derivative Holdings (Post-Transaction)0
No derivative holdings reported