Tiffany Olson - 22 May 2026 Form 4 Insider Report for CASTLE BIOSCIENCES INC (CSTL)

Reporting relationship: Director
Issuer ticker: CSTL
Reported as of: 22 May 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 27 May 2026, 16:17:46 UTC
Prior SEC filing: 23 Jun 2025
Next SEC filing: 01 Jun 2026
Source filing: View source filing
Reporting owner signature: /s/ Frank Stokes, Attorney-in-fact

Key filing fact

Tiffany Olson filed Form 4 for CASTLE BIOSCIENCES INC (CSTL) on 27 May 2026.

Key facts

This page summarizes Tiffany Olson's Form 4 filing for CASTLE BIOSCIENCES INC (CSTL).
2 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 27 May 2026, 16:17.

Change

Previous filing in this sequence was filed on 23 Jun 2025.
Current net transaction value: $0.

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 0001442172 Primary reporting owner

Olson Tiffany

Relationship: Director
Address: C/O CASTLE BIOSCIENCES, INC., 1500 W. PARKWOOD AVE SUITE 400, FRIENDSWOOD
Signature: /s/ Frank Stokes, Attorney-in-fact
Signature date: 27 May 2025

Reported non-derivative transactions

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

CSTL transaction

Common Stock

Options Exercise

Transaction value
Shares: +13,667
Change %: +53%
Price
Shares after: 39,573
Date: 22 May 2026
Ownership: Direct
Footnotes: F1

Reported derivative securities

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

CSTL transaction Derivative

Restricted Stock Units

Options Exercise

Transaction value
Shares: -13,667
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 22 May 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 13,667
Exercise price
Footnotes: F1, F2

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

Each Restricted Stock Unit ("RSU") represents the right to receive one share of the Issuer's Common Stock.

Footnote F2

The RSUs vest in full on the earlier of the (a) one-year anniversary of the date on May 22, 2026, or (b) the day immediately preceding the next Annual Meeting of Stockholders following the date of the grant.