MAETZOLD DEREK J 4

4 · CASTLE BIOSCIENCES INC · Filed Mar 5, 2026

Insider Transaction Report

Form 4

Period: 2026-03-03

CASTLE BIOSCIENCES INCCSTL

MAETZOLD DEREK J

DirectorPres. & Chief Exec. Officer

Transactions

Tax Payment
Common Stock
[F1]
2026-03-03$27.57/sh−19,043$525,016→ 64,655 total
Exercise/Conversion
Common Stock
[F2]
2026-03-04+59,097→ 123,752 total
Tax Payment
Common Stock
2026-03-04$28.17/sh−17,931$505,116→ 105,821 total
Award
Restricted Stock Units
[F2][F12]
2026-03-03+102,597→ 102,597 total
→ Common Stock (102,597 underlying)
Exercise/Conversion
Restricted Stock Units
[F2][F13]
2026-03-04−31,110→ 62,218 total
→ Common Stock (31,110 underlying)
Exercise/Conversion
Restricted Stock Units
[F2][F14]
2026-03-04−27,987→ 83,961 total
→ Common Stock (27,987 underlying)

Holdings

Common Stock
[F3]
(indirect: By Trust)
52,923
Common Stock
[F4]
(indirect: By Trust)
44,986
Common Stock
[F5]
(indirect: By Trust)
3,618
Common Stock
[F6]
(indirect: By Trust)
3,615
Common Stock
[F7]
(indirect: By Trust)
3,615
Common Stock
[F8]
(indirect: By Trust)
3,615
Common Stock
[F9]
(indirect: By Trust)
85,959
Common Stock
[F10]
(indirect: By Trust)
18,718
Common Stock
[F11]
(indirect: By Trust)
44,323

Footnotes (14)

[F1]Reflects the withholding of shares of the Issuer's common stock to satisfy tax withholding obligations in connection with the delivery of vested performance stock units reported on January 12, 2026.
[F10]Held by DJM Grantor Retained Annuity Trust No. 6 of which the Reporting Person is the trustee and the beneficiaries are The Maetzold 2018 Remainder Trust FBO John Derek Maetzold, The Maetzold 2018 Remainder Trust FBO Emily Carol Kirk, The Maetzold 2018 Remainder Trust FBO Peter Douglas Maetzold and The Maetzold 2018 Remainder Trust FBO Hannah Elizabeth Maetzold.
[F11]Held by DJM Grantor Retained Annuity Trust No. 7 of which the Reporting Person is the trustee and beneficiary.
[F12]The RSU's vest in four equal annual installments beginning on March 03, 2027.
[F13]On March 4, 2024, the Reporting Person was granted 124,437 RSUs which vest in four equal installments beginning on March 4, 2025.
[F14]On March 4, 2025, the Reporting Person was granted 111,948 RSUs which vest in four equal installments beginning on March 4, 2026.
[F2]Each Restricted Stock Unit ("RSU") represents the right to receive one share of the Issuer's Common Stock.
[F3]Held by The Maetzold Descendants 2020 Trust of which the Reporting Person's spouse is the trustee and the Reporting Person's spouse and their children are beneficiaries.
[F4]Held by Derek Maetzold 2020 Irrevocable Trust of which the Reporting Person is the trustee and his children are beneficiaries.
[F5]Held by The Maetzold 2018 Remainder Trust FBO Emily Carol Kirk of which the Reporting Person is the trustee and his child is the beneficiary.
[F6]Held by The Maetzold 2018 Remainder Trust FBO Hannah Elizabeth Maetzold of which the Reporting Person is the trustee and his child is the beneficiary.
[F7]Held by The Maetzold 2018 Remainder Trust FBO John Derek Maetzold of which the Reporting Person is the trustee and his child is the beneficiary.
[F8]Held by The Maetzold 2018 Remainder Trust FBO Peter Douglas Maetzold of which the Reporting Person is the trustee and his child is the beneficiary.
[F9]Held by DJM Grantor Retained Annuity Trust No. 5 of which the Reporting Person is the trustee and beneficiary.

Signature

/s/ Frank Stokes, Attorney-in-fact|2025-03-05

Documents

1 file

4
wk-form4_1772748733.xmlPrimary
FORM 4