[Form 4] Castle Biosciences, Inc. Insider Trading Activity

Rhea-AI Filing Summary

Castle Biosciences insider activity: The reporting person, Tobin W. Juvenal (Chief Commercial Officer), reported acquisition and disposition of common stock on 08/08/2025. He acquired 10,640 shares through performance-based stock units (PSUs) at $0 and disposed of 4,294 shares at $19.36. The PSUs are described as representing one share each and constitute the remaining 50% of a grant from December 23, 2022, which vested on August 9, 2024.

After the reported transactions the form shows 84,527 shares directly beneficially owned and 2,230 shares held indirectly by the Tobin W. and Susan M. Juvenal Family Revocable Trust. The report was submitted on behalf of the reporting person by an attorney-in-fact.

Positive

• 10,640 PSUs acquired at $0, reflecting the conversion of performance-based awards into common shares
• PSUs explicitly described as one-for-one rights to common stock and tied to a December 23, 2022 grant that vested on August 9, 2024
• Indirect trust holdings disclosed (2,230 shares), improving transparency about attributable ownership

Negative

• 4,294 shares sold at $19.36, reducing direct shareholdings
• Beneficial ownership decreased to 84,527 shares directly after the reported disposal

Insights

Financial Analyst

TL;DR: Officer received 10,640 PSUs and sold 4,294 shares at $19.36, leaving 84,527 shares directly owned; routine compensation and sale.

The filing shows compensation-related equity (10,640 PSUs) converting to common shares at no cash outlay and a contemporaneous cash sale of 4,294 shares at $19.36. This combination—vesting-driven acquisition plus a partial disposition—is consistent with typical executive liquidity following award vesting. The net direct holding reported is 84,527 shares, with an additional 2,230 shares held indirectly via a family trust. Impact on shareholders is informational; the filing does not state transaction rationale or signal material change to corporate strategy.

Corporate Governance Expert

TL;DR: Disclosure documents vesting and sale activity; PSUs described explicitly and trust holdings disclosed, meeting Section 16 reporting expectations.

The Form 4 documents time-based PSU conversion and an open-market disposition consistent with standard insider reporting. The form identifies the reporting persons officer role and discloses the family revocable trust as an indirect holder, clarifying potential attribution. From a governance perspective the filing provides the required transparency on executive compensation realization and related share moves; it does not allege issues of compliance or control deficiencies within the submitted information.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Juvenal Tobin W

(Last) (First) (Middle)

C/O CASTLE BIOSCIENCES, INC.

505 S FRIENDSWOOD DRIVE, SUITE 401

(Street)

FRIENDSWOOD TX 77546

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
CASTLE BIOSCIENCES INC [ CSTL ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Commercial Officer

3. Date of Earliest Transaction (Month/Day/Year)
08/08/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	08/08/2025		M		10,640	A	$0	88,821	D
Common Stock	08/08/2025		F		4,294	D	$19.36	84,527	D
Common Stock								2,230	I	By Tobin W and Susan M Juvenal Family Revocable Trust(1)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Performance-Based Stock Unit	(2)	08/08/2025		M			10,640	(2)	(2)	Common Stock	10,640	$0	0	D

Explanation of Responses:

1. Held by Tobin W and Susan M Juvenal Family Revocable Trust of which the Reporting Person and his spouse are the trustees and the Reporting Person, his spouse and their children are the beneficiaries.

2. Each Performance-Based Stock Unit ("PSU") represents the right to receive one share of the Issuer's Common Stock. These PSUs represent the remaining 50% of the PSUs granted on December 23, 2022, which were all subject to time-based vesting and vested in full on the one-year anniversary of August 9, 2024.

Remarks:

	/s/ Frank Stokes, Attorney-in-fact	08/12/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transactions did CSTL report for Tobin W. Juvenal?

The Form 4 shows acquisition of 10,640 shares via performance-based stock units (PSUs) and disposition of 4,294 shares at $19.36, both dated 08/08/2025.

How many Castle Biosciences (CSTL) shares does Tobin Juvenal beneficially own after the transactions?

The filing reports 84,527 shares directly beneficially owned following the transactions and 2,230 shares held indirectly by the Tobin W. and Susan M. Juvenal Family Revocable Trust.

What are the PSUs reported on the CSTL Form 4?

Each Performance-Based Stock Unit represents the right to receive one share of common stock; these PSUs are the remaining 50% of a grant from 12/23/2022 and are stated to have vested on 08/09/2024.

What is Tobin Juvenal's role at Castle Biosciences according to the filing?

The reporting person is identified as an Officer with the title Chief Commercial Officer.

Was any indirect ownership disclosed in the CSTL Form 4 filing?

Yes. The filing discloses 2,230 shares held indirectly by the Tobin W. and Susan M. Juvenal Family Revocable Trust, of which the reporting person and spouse are trustees and family members are beneficiaries.