Castle Biosciences CSTL Insider Ownership

NASDAQ CSTL
$34.99 -0.35 (-0.99%)
At close: Sep 21, 2026 · 4:00 PM EDT

Insider Holdings by Owner

499.72K Shares

Insider Ownership Statistics

as of 30 Sep, 2026
Insider Ownership
1.91%
-0.547% pp QoQ
Shares Held by Insiders
580.30K
filed for Sep 2026
-22.29% QoQ
Shares Outstanding
30.40Mn
30,399,000 shares
Direct Holdings
427.99K
Indirect: 152.31K
Net Shares Traded (QoQ)
-166.43K
net selling in Sep 2026
Insiders Holding Shares
13
with Form 4 holdings on file

Shares Owned by Insiders

Shares held % of outstanding
Latest
Average ownership
Peak ownership

Shares Purchased/Sold by Insiders

Bought Sold
Latest quarter
Net over range
Buying quarters

Insider Ownership Summary

Quarter ending 30 Sep, 2026

As of September 17, 2026, Castle Biosciences's top three insider holders are Derek J Maetzold (Pres. Chief Exec. Officer, 93.20K shares), Kristen M Oelschlager (Chief Operating Officer, 72.65K shares), Tobin W Juvenal (Chief Commercial Officer, 58.58K shares).

Form 4 Holdings

Insiders Holding CSTL

Insiders 13
Shares held 499.72K
Of outstanding 1.64%
# Insider Position Direct Indirect Total Share of Insiders Last Filed
1 Derek J Maetzold Pres. Chief Exec. Officer 21,479 71,726 93,205 18.7% 15 Sep, 2026
2 Tobin W Juvenal Chief Commercial Officer 58,584 0 58,584 11.7% 16 Sep, 2026
3 Mara G. Aspinall Director 44,139 0 44,139 8.8% 04 Jun, 2024
4 Ellen Goldberg Director 40,921 0 40,921 8.2% 27 May, 2025
5 Tiffany Olson Director 39,573 0 39,573 7.9% 27 May, 2025
6 Kim Caple Director 36,121 0 36,121 7.2% 27 May, 2025
7 Miles Harrison Director 35,631 0 35,631 7.1% 27 May, 2025
8 Frank Stokes Chief Financial Officer 35,177 0 35,177 7.0% 18 Aug, 2026
9 Rodney Cotton Director 32,998 0 32,998 6.6% 27 May, 2025
10 G Bradley Cole Director 32,976 0 32,976 6.6% 27 May, 2026
11 Daniel Bradbury Director 22,340 0 22,340 4.5% 27 May, 2025
12 Bernhard E. Spiess Chief Business Officer 14,696 0 14,696 2.9% 14 Dec, 2021
13 Kristen M Oelschlager Chief Operating Officer 13,356 0 13,356 2.7% 03 Sep, 2026

Each row is that insider’s most recently reported position, from Form 4 filings over the last 60 months — which is why this total does not tie to the quarterly series above, where a quarter counts only the insiders who filed in it. Shares held through a fund or institutional portfolio are counted on the institutional ownership page instead.

Form 4 Filings

2,943 Insider Transactions

Source SEC Form 4
Latest quarter Sep 2026
Download Data
Date Insider Position Transaction Shares Price Value Shares Held After Ownership
01 Sep, 2026 Kristen M Oelschlager Chief Operating Officer Acquired M 4,152 $3.38 $14.03K 17,508 Direct
01 Sep, 2026 Kristen M Oelschlager Chief Operating Officer Disposed S 3,952 $33.36 $131.84K 13,556 Direct
01 Sep, 2026 Kristen M Oelschlager Chief Operating Officer Disposed S 200 $34.02 $6.80K 13,356 Direct
01 Sep, 2026 Kristen M Oelschlager Chief Operating Officer Disposed M 4,152 $0.00 $0 12,458 Direct
31 Aug, 2026 Tobin W Juvenal Chief Commercial Officer Disposed S 1,730 $32.81 $56.76K 65,184 Direct
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Acquired M 12,428 $2.39 $29.70K 33,907 Direct
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 11,472 $33.14 $380.18K 22,435 Direct
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 2,505 $33.14 $83.02K 17,850 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 2,129 $33.14 $70.56K 15,172 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 257 $33.14 $8.52K 11,277 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 257 $33.14 $8.52K 11,277 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 257 $33.14 $8.52K 11,277 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 257 $33.14 $8.52K 11,277 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 956 $33.88 $32.39K 21,479 Direct
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 209 $33.88 $7.08K 17,641 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 177 $33.88 $6.00K 14,995 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 21 $33.88 $711 11,256 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 21 $33.88 $711 11,256 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 21 $33.88 $711 11,256 Indirect
28 Aug, 2026 Derek J Maetzold Pres. Chief Exec. Officer Disposed S 21 $33.88 $711 11,256 Indirect