Changes in Beneficial Ownership · 4
Castle Biosciences, Inc.
CSTLNASDAQEQUITYCurrent
Changes in Beneficial Ownership
Structured filing — 4
wk-form4_1791403842.xml
Filing details
- Report period
- 2026-10-05
- Issuer
- CASTLE BIOSCIENCES INC
- Issuer CIK
- 0001447362
- Trading symbol
- CSTL
- Rule 10b5-1 indication
- Checked
Reporting owner 1
- Name
- MAETZOLD DEREK J
- Reporting owner CIK
- 0001239501
- Relationship
- Director · Officer
- Officer title
- Pres. & Chief Exec. Officer
- Address
- C/O CASTLE BIOSCIENCES, INC., 1500 W. PARKWOOD AVE SUITE 400, FRIENDSWOOD, TX, 77546
Non-derivative transactions
| Security | Transaction date | Code | Amount | A / D | Price (USD) | Owned after | Ownership | Nature of ownership |
|---|---|---|---|---|---|---|---|---|
| Common Stock | 2026-10-05 | M · Form 4[F1] | 8,165 | A | 2.39 | 29,644 | D | |
| Common Stock | 2026-10-05 | S · Form 4[F1] | 8,580 | D | 35.566[F2] | 21,064 | D | |
| Common Stock | 2026-10-05 | S · Form 4[F1] | 3,198 | D | 35.566[F2] | 8,038 | I | By The Maetzold Descendants 2020 Trust[F3] |
| Common Stock | 2026-10-05 | S · Form 4[F1] | 2,718 | D | 35.566[F2] | 6,832 | I | By Derek Maetzold 2020 Irrevocable Trust[F4] |
Table key
- M · Form 4
- Exempt derivative exercise or conversion under Rule 16b-3
- A
- Acquired
- D
- Disposed
- S · Form 4
- Sale on the market or privately
- I
- Indirect
Non-derivative holdings
| Security | Amount owned | Ownership | Nature of ownership |
|---|---|---|---|
| Common Stock | 11,256 | I | By The Maetzold 2018 Remainder Trust FBO Emily Carol Kirk[F5] |
| Common Stock | 11,256 | I | By The Maetzold 2018 Remainder Trust FBO Hannah Elizabeth Maetzold[F6] |
| Common Stock | 11,256 | I | By The Maetzold 2018 Remainder Trust FBO John Derek Maetzold[F7] |
| Common Stock | 11,256 | I | By The Maetzold 2018 Remainder Trust FBO Peter Douglas Maetzold[F8] |
| Common Stock | 11,963 | I | By DJM Grantor Retained Annuity Trust No. 6[F9] |
| Common Stock | 27,862 | I | By DJM Grantor Retained Annuity Trust No. 7[F10] |
| Common Stock | 40,935 | I | By DJM Grantor Retained Annuity Trust No. 8[F11] |
| Common Stock | 23,216 | I | DJM Grantor Retained Annuity Trust No. 9[F12] |
Table key
- I
- Indirect
Derivative transactions
| Security | Conversion / exercise price (USD) | Transaction date | Code | Amount | A / D | Price (USD) | Exercisable | Expires | Underlying security | Underlying shares | Owned after | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Stock option (right to buy) | 2.39 | 2026-10-05 | M · Form 4[F1] | 8,165 | D | 0 | [F13] | 2028-05-09 | Common Stock | 8,165 | 0 | D |
Table key
- M · Form 4
- Exempt derivative exercise or conversion under Rule 16b-3
- D
- Direct
Footnotes
- F1
- These transactions were made pursuant to a Rule 10b5-1 plan adopted by the Reporting Person on June 2, 2026.↩ 1↩ 2↩ 3↩ 4↩ 5
- F2
- This transaction was executed in multiple trades at prices ranging from $35.310 to $35.965, 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.↩ 1↩ 2↩ 3
- 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.↩ 1
- F4
- Held by Derek Maetzold 2020 Irrevocable Trust of which the Reporting Person is the trustee and his children are beneficiaries.↩ 1
- F5
- 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.↩ 1
- F6
- 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.↩ 1
- F7
- 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.↩ 1
- F8
- 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.↩ 1
- F9
- 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.↩ 1
- F10
- Held by DJM Grantor Retained Annuity Trust No. 7 of which the Reporting Person is the trustee and beneficiary.↩ 1
- F11
- Held by DJM Grantor Retained Annuity Trust No. 8 of which the Reporting Person is the trustee and beneficiary.↩ 1
- F12
- Held by DJM Grantor Retained Annuity Trust No. 9 of which the Reporting Person is the trustee and beneficiary.↩ 1
- F13
- The shares subject to the option are fully vested.↩ 1
Signature 1
- Signed
- /s/ Frank Stokes, Attorney-in-fact
- Date
- 2026-10-07