Total buying$00 buys
CSTL
CASTLE BIOSCIENCES INC
NasdaqHealthcareServices-Medical Laboratories
Insider activity for last month from 09/19 to 10/19.
How these metrics are calculated
Counts use processed Form 4 rows. Purchase and sale metrics use codes P and S; totals remain unknown when any matching value is missing. Rows without a usable transaction date cannot be assigned to a rolling period and are excluded.
Total selling$1.51M11 sells
Net open-market−$1.51MBuying minus selling
Active insiders3Distinct reporting owners
Insider activity report
Calendar-month buckets within the selected date range
Latest filing: Oct 14, 2026
Open-market transaction mix · 11 transactions in the selected period
Code A includes awards, grants and other acquisitions; these are not open-market buys. A rolling period can include partial calendar months.
View exact monthly counts and disclosed values
| Month | Buys | Sells | Awards (A) | Buy value | Sell value | Net P/S value |
|---|---|---|---|---|---|---|
| Sep 2026 | 0 | 5 | 0 | $0 | $744k | -$744k |
| Oct 2026 | 0 | 6 | 0 | $0 | $775k | -$775k |
Distinct insiders active
Reporting-owner CIKs by month · peak Oct 2026 (3)Sep 2026Oct 2026
Largest insider activity
By absolute net disclosed value · current transaction page- MJ-$987.7k
- JW-$342.7k
- OM-$135.3k
CSTL transaction history
Newest filings · 20 transactions per pageLatest insider transactions
Form 4 filings from last month.| Company | Insider | Activity | Disclosed value | Filed (ET) |
|---|---|---|---|---|
CSTLCASTLE BIOSCIENCES INC | Juvenal Tobin WCCO | S · sale10b5-1 detectedSEC filing ↗ | -$110kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | M · exercise10b5-1 detectedDerivative securitySEC filing ↗ | $0View disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | S · sale10b5-1 detectedSEC filing ↗ | -$96.6kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | S · sale10b5-1 detectedSEC filing ↗ | -$113kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | S · sale10b5-1 detectedSEC filing ↗ | -$305kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | M · exercise10b5-1 detectedSEC filing ↗ | $19.5kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Oelschlager Kristen MCOO | M · exercise10b5-1 detectedDerivative securitySEC filing ↗ | $0View disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Oelschlager Kristen MCOO | S · sale10b5-1 detectedSEC filing ↗ | -$48.9kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Oelschlager Kristen MCOO | S · sale10b5-1 detectedSEC filing ↗ | -$100kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Oelschlager Kristen MCOO | M · exercise10b5-1 detectedSEC filing ↗ | $14.0kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Juvenal Tobin WCCO | S · sale10b5-1 detectedSEC filing ↗ | -$35.3kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Juvenal Tobin WCCO | S · sale10b5-1 detectedSEC filing ↗ | -$196kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | M · exercise10b5-1 detectedDerivative securitySEC filing ↗ | $0View disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | S · sale10b5-1 detectedSEC filing ↗ | -$96.0kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | S · sale10b5-1 detectedSEC filing ↗ | -$112kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | S · sale10b5-1 detectedSEC filing ↗ | -$303kView disclosure → | |
CSTLCASTLE BIOSCIENCES INC | Maetzold Derek JPRES · CEO | M · exercise10b5-1 detectedSEC filing ↗ | $20.5kView disclosure → |
Filing-only signals
Deterministic matches in the selected period
Filing detail checks
Secondary metrics for the selected periodTransaction codes
By Form 4 transaction code in selected period17transactionstxns
- S · Open-market sells · dominant11 · 65%
- M · Option exercise6 · 35%
Activity by reported role
A joint filing can contribute to multiple rolesChief executive officer10
PRES10
COO4
CCO3
Reported Holdings After
Separated by insider, security, and ownership type
Maetzold Derek JCommon Stock · Direct
21,064Oct 05, 2026
Juvenal Tobin WCommon Stock · Direct
48,719Oct 12, 2026
Oelschlager Kristen MCommon Stock · Direct
13,356Oct 01, 2026
Maetzold Derek JCommon Stock · Indirect · By The Maetzold Descendants 2020 Trust
8,038Oct 05, 2026
Maetzold Derek JCommon Stock · Indirect · By Derek Maetzold 2020 Irrevocable Trust
6,832Oct 05, 2026
Maetzold Derek JStock option (right to buy) · Direct
0Oct 05, 2026
Oelschlager Kristen MStock option (right to buy) · Direct
8,305Oct 01, 2026
These are reported post-transaction holdings, not company-wide ownership percentages. Securities, indirect vehicles, and amendments are kept separate.
Filing activity heatmap
Current transaction page only · each cell is a filing date · buys green, sells redSep 19 → Oct 19
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CASTLE BIOSCIENCES INC Insider Activity FAQ
SEC Form 4 contextWho recently reported transactions at CASTLE BIOSCIENCES INC?
Juvenal Tobin W, MAETZOLD DEREK J, Oelschlager Kristen M.
When was the latest reported open-market purchase?
No code-P purchase is available for this period.
When was the latest reported open-market sale?
Juvenal Tobin W reported a sale on Oct 12, 2026 valued at $110k. Read the SEC filing.
What is the recent purchase and sale balance?
Net open-market selling in the selected period was $1,519,820.66. Sales can occur for many non-investment reasons.
Where can I see the original SEC filing?
Every transaction row and latest-activity fact links to its original SEC filing.
What do these Form 4 transaction codes mean?
P and S generally describe open-market or private purchases and sales. A, D, F, M, X, G, J, and V describe awards, issuer dispositions, tax withholding, exercises, gifts, other transactions, and voluntary early reports; review each filing and its footnotes for context.