Castle Biosciences (CSTL) CEO logs Rule 10b5-1 common stock sale
Rhea-AI Filing Summary
Castle Biosciences Inc. reported an insider stock sale by a director who also serves as president and chief executive officer. On December 4, 2025, the insider sold 1,339 shares of common stock at a weighted-average price of $40.03 per share in a transaction made under a contract, instruction or written plan intended to satisfy Rule 10b5-1(c), which was adopted on May 8, 2025.
After this sale, the insider directly owned 37,547 shares of Castle Biosciences common stock and reported additional indirect holdings through several family trusts, including 52,923 shares held by The Maetzold Descendants 2020 Trust and 44,986 shares held by the Derek Maetzold 2020 Irrevocable Trust.
Positive
- None.
Negative
- None.
Insider Trade Summary
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock | 1,339 | $40.03 | $54K |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
| holding | Common Stock | -- | -- | -- |
Footnotes (1)
- These transactions were made pursuant to a Rule 10b5-1 plan adopted by the Reporting Person on May 8, 2025. This transaction was executed in multiple trades at prices ranging from $40.00 to $40.11, 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. 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. Held by Derek Maetzold 2020 Irrevocable Trust of which the Reporting Person is the trustee and his children are beneficiaries. 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. 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. 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. 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. Held by DJM Grantor Retained Annuity Trust No. 5 of which the Reporting Person is the trustee and beneficiary. 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. Held by DJM Grantor Retained Annuity Trust No. 7 of which the Reporting Person is the trustee and beneficiary.
FAQ
What insider stock transaction did Castle Biosciences (CSTL) report?
The filing reports that a Castle Biosciences director who is also president and chief executive officer sold 1,339 shares of common stock on December 4, 2025 at a weighted-average price of $40.03 per share.
Was the CSTL insider sale made under a Rule 10b5-1 trading plan?
Yes. The filing states the transactions were made pursuant to a Rule 10b5-1 plan adopted by the reporting person on May 8, 2025, intended to satisfy the affirmative defense conditions of Rule 10b5-1(c).
Did the Castle Biosciences (CSTL) insider report any derivative securities?
The section for derivative securities (Table II) does not list any derivative securities acquired, disposed of, or beneficially owned for this reporting person.
What transaction pricing details are provided in the CSTL insider sale?
The sale of 1,339 shares was executed in multiple trades at prices ranging from $40.00 to $40.11 per share, with a reported weighted-average sale price of $40.03 per share.