Form4insider filings, from the source

Company · CIK 0001447362 · SIC 8071 — Services-Medical Laboratories · Nasdaq

CASTLE BIOSCIENCES INC · CSTL

Insider activity reported against this company. All insider holders · On EDGAR ↗

1M3M6M1Y2YAll datashares as filed — not split-adjusted
Open-market buys & salesbuys $0 · 0sales $2.0M · 6net −$2.0M
$10k$10k$100k$100k$1M$1MbuyssalesAug 28Sep 2Sep 7Sep 12Sep 18Sep 23Sep 28

Reported at this company — common stock

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Sep 21, 2026 SForm 4 →Sep 23, 4:27 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director14,496$35.33$512,2029,550−60.3%10b5-1
Sep 21, 2026 MForm 4 →Sep 23, 4:27 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director8,580$2.39$20,50630,059—10b5-1
Sep 14, 2026 SForm 4 →Sep 16, 4:20 pm EDTTobin W JuvenalChief Commercial Officer6,600$33.73$222,62158,584−10.1%10b5-1
Sep 11, 2026 SForm 4 →Sep 15, 4:08 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director14,518$32.02$464,87012,268−54.2%10b5-1
Sep 11, 2026 MForm 4 →Sep 15, 4:08 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director8,584$2.39$20,51630,063—10b5-1
Sep 1, 2026 SForm 4 →Sep 3, 4:07 pm EDTKristen M OelschlagerChief Operating Officer4,152$33.39$138,64313,356−23.7%10b5-1
Sep 1, 2026 MForm 4 →Sep 3, 4:07 pm EDTKristen M OelschlagerChief Operating Officer4,152$3.38$14,03417,508—10b5-1
Aug 31, 2026 SForm 4 →Sep 2, 4:07 pm EDTTobin W JuvenalChief Commercial Officer1,730$32.81$56,76165,184−2.59%10b5-1
Aug 28, 2026 SForm 4 →Sep 1, 4:12 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director18,560$33.20$616,13411,256−62.2%10b5-1
Aug 28, 2026 MForm 4 →Sep 1, 4:12 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director12,428$2.39$29,70333,907—10b5-1

Reported at this company — derivatives (options, RSUs, warrants)

TradeReported (ET)InsiderSharesAvg priceTotalOwned afterΔ stakeFlags
Sep 21, 2026 MForm 4 →Sep 23, 4:27 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director8,580——8,165—10b5-1
Sep 11, 2026 MForm 4 →Sep 15, 4:08 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director8,584——16,745—10b5-1
Sep 1, 2026 MForm 4 →Sep 3, 4:07 pm EDTKristen M OelschlagerChief Operating Officer4,152——12,458—10b5-1
Aug 28, 2026 MForm 4 →Sep 1, 4:12 pm EDTDerek J MaetzoldPres. & Chief Exec. Officer, Director12,428——25,329—10b5-1