MAETZOLD DEREK J 4
4 · CASTLE BIOSCIENCES INC · Filed Mar 17, 2026
Research Summary
AI-generated summary of this filing
Castle Biosciences (CSTL) CEO Derek Maetzold Sells Shares
What Happened
Derek J. Maetzold, President & Chief Executive Officer and a director of Castle Biosciences (CSTL), sold a total of 30,779 shares in open-market transactions between March 13 and March 16, 2026, generating approximately $792,410 in proceeds. The sales were carried out pursuant to a Rule 10b5-1 trading plan adopted December 3, 2025, and the reported prices (weighted averages where applicable) were $25.45, $25.96 and $26.68.
Key Details
- Transaction dates and amounts:
- 2026-03-13: 13,204 shares sold at a weighted-average price of $25.45 for $336,002. (Footnote F2: multiple trades at $25.210–$25.785)
- 2026-03-16: 17,449 shares sold at a weighted-average price of $25.96 for $453,046. (Footnote F3: multiple trades at $25.660–$26.630)
- 2026-03-16: 126 shares sold at $26.68 for $3,362.
- Total shares sold: 30,779; total proceeds: ~$792,410.
- Shares owned after the transactions: not specified in the information provided in this summary.
- Notable footnotes: sales were made under a 10b5-1 plan (F1); some holdings referenced in the filing are held in various family or grantor retained annuity trusts (F4–F12).
- Filing/timeliness: Form 4 filed March 17, 2026 (covers trades on 3/13 and 3/16); filing appears to be within the standard two-business-day reporting window.
Context
These are open-market sales (code S) executed under a pre-established 10b5-1 plan. Such sales are generally considered routine liquidity transactions under a trading plan and do not by themselves indicate management’s view of the company’s near-term prospects. The filing includes weighted-average prices and notes that detailed trade-level data is available upon request to the SEC or issuer.
Insider Transaction Report
- Sale
Common Stock
[F1][F2]2026-03-13$25.45/sh−13,204$336,002→ 58,354 total - Sale
Common Stock
[F1][F3]2026-03-16$25.96/sh−17,449$453,046→ 40,905 total - Sale
Common Stock
[F1]2026-03-16$26.68/sh−126$3,362→ 40,779 total
- 51,566(indirect: By Trust)
Common Stock
[F4] - 43,826(indirect: By Trust)
Common Stock
[F5] - 3,336(indirect: By Trust)
Common Stock
[F6] - 3,336(indirect: By Trust)
Common Stock
[F7] - 3,336(indirect: By Trust)
Common Stock
[F8] - 3,336(indirect: By Trust)
Common Stock
[F9] - 85,959(indirect: By Trust)
Common Stock
[F10] - 18,718(indirect: By Trust)
Common Stock
[F11] - 44,323(indirect: By Trust)
Common Stock
[F12]
Footnotes (12)
- [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. 5 of which the Reporting Person is the trustee and beneficiary.
- [F11]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.
- [F12]Held by DJM Grantor Retained Annuity Trust No. 7 of which the Reporting Person is the trustee and beneficiary.
- [F2]This transaction was executed in multiple trades at prices ranging from $25.210 to $25.785, 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 $25.660 to $26.630, 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]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.
- [F5]Held by Derek Maetzold 2020 Irrevocable Trust of which the Reporting Person is the trustee and his children are beneficiaries.
- [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.