MAETZOLD DEREK J 4
4 · CASTLE BIOSCIENCES INC · Filed Jun 17, 2026
Research Summary
AI-generated summary of this filing
Castle Biosciences (CSTL) CEO Derek Maetzold Sells 86,192 Shares
What Happened
- Derek J. Maetzold, President & Chief Executive Officer of Castle Biosciences (CSTL), executed option exercises and multiple open-market sales on June 15, 2026. He exercised 550 shares at $2.39 (cost $1,315) and recorded another 550-share derivative conversion/transfer shown at $0.00. Separately, he sold a total of 86,192 shares in multiple open-market transactions at a weighted-average price of $20.66 for aggregate reported proceeds of $86,192. These transactions were reported on a Form 4 filed June 17, 2026.
Key Details
- Transaction date: June 15, 2026; Form 4 filed June 17, 2026 (timely).
- Sales: 86,192 shares sold in multiple trades; weighted-average sale price $20.66 (trades ranged $20.44–$20.98 per footnote).
- Option exercise: 550 shares exercised at $2.39 (cost $1,315); an additional 550-share derivative conversion shown with $0.00 value.
- Plan/authority: Sales executed pursuant to a Rule 10b5-1 trading plan adopted Dec 3, 2025 (footnote).
- Vesting: The option(s) involved are fully vested (footnote F13).
- Shares owned after transaction: Not specified in the provided filing excerpt.
- Other notes: Filing includes several family trust transfer footnotes dated June 10, 2026 describing reallocations among Maetzold trusts.
Context
- This pattern—exercising vested options and selling shares under a pre-established 10b5-1 plan—is common for executives managing option exercises, tax obligations, or diversification and does not by itself indicate a change in company outlook. The filing shows both an exercise and immediate sales (consistent with cashless or planned-sale treatment) and includes a zero-dollar derivative disposition that likely reflects a non-cash transfer or surrender as recorded on the Form 4.
Insider Transaction Report
Form 4
MAETZOLD DEREK J
DirectorPres. & Chief Exec. Officer
Transactions
- Exercise/Conversion
Common Stock
[F1]2026-06-15$2.39/sh+550$1,315→ 22,029 total - Sale
Common Stock
[F1][F2]2026-06-15$20.66/sh−550$11,363→ 21,479 total - Sale
Common Stock
[F1][F2][F3]2026-06-15$20.66/sh−1,357$28,036→ 42,067 total(indirect: By Trust) - Sale
Common Stock
[F1][F2][F4]2026-06-15$20.66/sh−1,153$23,821→ 35,755 total(indirect: By Trust) - Sale
Common Stock
[F1][F2][F5][F6]2026-06-15$20.66/sh−278$5,743→ 12,646 total(indirect: By Trust) - Sale
Common Stock
[F1][F2][F5][F7]2026-06-15$20.66/sh−278$5,743→ 12,646 total(indirect: By Trust) - Sale
Common Stock
[F1][F2][F5][F8]2026-06-15$20.66/sh−278$5,743→ 12,646 total(indirect: By Trust) - Sale
Common Stock
[F1][F2][F5][F9]2026-06-15$20.66/sh−278$5,743→ 12,646 total(indirect: By Trust) - Exercise/Conversion
Stock option (right to buy)
[F1][F13]2026-06-15−550→ 91,881 totalExercise: $2.39Exp: 2028-05-09→ Common Stock (550 underlying)
Holdings
- 18,718(indirect: By Trust)
Common Stock
[F10] - 44,323(indirect: By Trust)
Common Stock
[F11] - 40,935(indirect: By Trust)
Common Stock
[F12]
Footnotes (13)
- [F1]These transactions were made pursuant to a Rule 10b5-1 plan adopted by the Reporting Person on December 3, 2025.
- [F10]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.
- [F11]Held by DJM Grantor Retained Annuity Trust No. 7 of which the Reporting Person is the trustee and beneficiary.
- [F12]Held by DJM Grantor Retained Annuity Trust No. 8 of which the Reporting Person is the trustee and beneficiary. On June 10, 2026, 40,935 shares of common stock were transferred from DJM Grantor Annuity Trust No. 5 to the Reporting Person's direct holdings, and subsequently transferred from the Reporting Person's direct holdings to DJM Grantor Retained Annuity Trust No. 8.
- [F13]The shares subject to the option are fully vested.
- [F2]This transaction was executed in multiple trades at prices ranging from $20.44 to $20.98, 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]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.
- [F4]Held by Derek Maetzold 2020 Irrevocable Trust of which the Reporting Person is the trustee and his children are beneficiaries.
- [F5]Reflects the transfers on June 10, 2026, of 45,024 shares of common stock from DJM Grantor Annuity Trust No. 5, of which, 11,256 transferred to The Maetzold 2018 Remainder Trust FBO Emily Carol Kirk, 11,256 transferred to The Maetzold 2018 Remainder Trust FBO Hannah Elizabeth Maetzold, 11,256 transferred to The Maetzold 2018 Remainder Trust FBO John Derek Maetzold and 11,256 transferred to The Maetzold 2018 Remainder Trust FBO Peter Douglas Maetzold. The remaining 40,935 shares of common stock held by DJM Grantor Annuity Trust No. 5 were transferred as described in footnote 12, after which DJM Grantor Annuity Trust No. 5 holds no remaining shares of common stock.
- [F6]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.
- [F7]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.
- [F8]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.
- [F9]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.
Signature
/s/ Frank Stokes, Attorney-in-fact|2026-06-17