Castle Biosciences (CSTL) CEO reports stock sales under 10b5-1 plan
Rhea-AI Filing Summary
Castle Biosciences Inc. reported insider stock sales by its president, chief executive officer and director. On 12/15/2025, the reporting person sold 18,513 shares of common stock at a weighted-average price of $38.747 and 1,012 shares at $39.304. On 12/16/2025, they sold an additional 12,821 shares at a weighted-average price of $38.554. These trades were made under a Rule 10b5-1 trading plan adopted on May 8, 2025. After the reported sales, the reporting person directly owns 34,869 shares of common stock and also has indirect beneficial ownership of multiple blocks of shares through several family and grantor retained annuity trusts.
Positive
- None.
Negative
- None.
Insider Trade Summary
| Type | Security | Shares | Price | Value |
|---|---|---|---|---|
| Sale | Common Stock | 12,821 | $38.554 | $494K |
| Sale | Common Stock | 18,513 | $38.747 | $717K |
| Sale | Common Stock | 1,012 | $39.304 | $40K |
| holding | Common Stock | -- | -- | -- |
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| holding | Common Stock | -- | -- | -- |
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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 $38.240 to $39.220, 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. This transaction was executed in multiple trades at prices ranging from $39.240 to $39.390, 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. This transaction was executed in multiple trades at prices ranging from $38.135 to $39.070, 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 transaction did Castle Biosciences (CSTL) disclose in this Form 4?
The filing reports that the president, chief executive officer and director of Castle Biosciences Inc. sold common stock in several transactions on 12/15/2025 and 12/16/2025 under a pre-established Rule 10b5-1 trading plan.
Is the Castle Biosciences (CSTL) insider sale part of a Rule 10b5-1 plan?
Yes. The filing states that these transactions were made pursuant to a Rule 10b5-1 plan adopted by the reporting person on May 8, 2025, which is a pre-arranged trading plan for equity securities.
What indirect holdings in Castle Biosciences (CSTL) are reported through trusts?
The filing lists indirect beneficial ownership in several trusts, including The Maetzold Descendants 2020 Trust, the Derek Maetzold 2020 Irrevocable Trust, multiple 2018 Remainder Trusts for family members, and DJM Grantor Retained Annuity Trusts Nos. 5, 6 and 7.
What role does the reporting person hold at Castle Biosciences (CSTL)?
The reporting person is identified as a director and as an officer of Castle Biosciences Inc., serving as President & Chief Executive Officer.