CASTLE BIOSCIENCES INC — Director's Dealing 2021

May 27, 2021

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CASTLE BIOSCIENCES INC (CSTL)
CIK: 0001447362
Period of Report: 2021-05-25

Reporting Person: MAETZOLD DEREK J (Director, Pres. & Chief Exec. Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2021-05-25	Common Stock	S	8599	$60.50	Disposed	546020	Direct
2021-05-26	Common Stock	S	2433	$58.66	Disposed	543587	Direct
2021-05-26	Common Stock	S	585	$59.97	Disposed	543002	Direct
2021-05-26	Common Stock	S	1015	$60.86	Disposed	541987	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	156460	Indirect
Common Stock	179300	Indirect
Common Stock	166700	Indirect

Footnotes

F1: These transactions were made pursuant to a Rule 10b5-1 plan adopted by the Reporting Person on December 11, 2020.

F2: This transaction was executed in multiple trades at prices ranging from $60.01 to $60.97, 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.

F3: This transaction was executed in multiple trades at prices ranging from $58.35 to $59.19, 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.

F4: This transaction was executed in multiple trades at prices ranging from $59.35 to $60.34, 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.

F5: This transaction was executed in multiple trades at prices ranging from $60.43 to $61.27, 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.

F6: Held by DJM Grantor Retained Annuity Trust No. 1 of which the Reporting Person is the trustee and beneficiary.

F7: 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.

F8: Held by Derek Maetzold 2020 Irrevocable Trust of which the Reporting Person is the trustee and his children are beneficiaries.