G. Bradley Cole - 05 Mar 2026 Form 4 Insider Report for CASTLE BIOSCIENCES INC (CSTL)

Reporting relationship: Director
Issuer ticker: CSTL
Reported as of: 05 Mar 2026
Net transaction value: -$210,727
SEC form: 4
Accepted by SEC: 09 Mar 2026, 16:12:43 UTC
Prior SEC filing: 05 Jun 2025
Next SEC filing: 27 May 2026
Source filing: View source filing
Reporting owner signature: /s/ Frank Stokes, Attorney-in-fact

Key filing fact

G. Bradley Cole filed Form 4 for CASTLE BIOSCIENCES INC (CSTL) on 09 Mar 2026.

Key facts

This page summarizes G. Bradley Cole's Form 4 filing for CASTLE BIOSCIENCES INC (CSTL).
4 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 09 Mar 2026, 16:12.

Change

Previous filing in this sequence was filed on 05 Jun 2025.
Current net transaction value: -$210,727.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001337798 Primary reporting owner

Cole G Bradley

Relationship: Director
Address: C/O CASTLE BIOSCIENCES, INC., 1500 W. PARKWOOD AVE SUITE 400, FRIENDSWOOD
Signature: /s/ Frank Stokes, Attorney-in-fact
Signature date: 09 Mar 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

CSTL transaction

Common Stock

Options Exercise

Transaction value
Shares: +4,748
Change %: +22%
Price: $3.38^*
Shares after: 26,712
Date: 05 Mar 2026
Ownership: Direct

CSTL transaction

Common Stock

Sale

Transaction value: $135,033
Shares: -4,748
Change %: -18%
Price: $28.44
Shares after: 21,964
Date: 05 Mar 2026
Ownership: Direct
Footnotes: F1

CSTL transaction

Common Stock

Sale

Transaction value: $75,694
Shares: -2,655
Change %: -12%
Price: $28.51
Shares after: 19,309
Date: 05 Mar 2026
Ownership: Direct
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

CSTL transaction Derivative

Stock option (right to buy)

Options Exercise

Transaction value
Shares: -4,748
Change %: -19%
Price: $0.000000^*
Shares after: 20,000
Date: 05 Mar 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 4,748
Exercise price: $3.38
Footnotes: F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 3 footnotes

Footnote F1

This transaction was executed in multiple trades at prices ranging from $28.39 to $28.51, inclusive. The price reported above reflects the weighted-average sale price. The Reporting Person hereby undertakes to provide upon request to the Securities and Exchange Commission staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

Footnote F2

This transaction was executed in multiple trades at prices ranging from $28.47 to $28.57, inclusive. The price reported above reflects the weighted-average sale price. The Reporting Person hereby undertakes to provide upon request to the Securities and Exchange Commission staff, the issuer or a security holder of the issuer full information regarding the number of shares and prices at which the transaction was effected.

Footnote F3

The shares subject to the option are fully vested.