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CSTL Insider Trading: Insider Buys and Sells · https://wallstpal.com/stock/cstl/insider-trading/ · saved 2026-10-28

About this page

Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.

How to read it

Form 4
The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
Buy (P) and Sell (S)
Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
Value
Shares times price, as reported on the filing.
10b5-1
A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
Late filing
A Form 4 filed more than two business days after the trade.
Vs. S&P 500
How the stock did after the trade minus how the overall market did in the same weeks.

A real example

In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.

Explain it like I'm 13

If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.

Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.

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Insider tradingForm 4

CASTLE BIOSCIENCES INC (CSTL) Insider Trading

47 open-market trades reported since Jun 17, 2026: 0 purchases worth $0 and 47 sales worth $9.63M.

By insider

InsiderRoleBuysBoughtSellsSoldLatest
Derek J. MaetzoldPres. & Chief Exec. Officer0$028$5.53MOct 21, 2026
Tobin W. JuvenalChief Commercial Officer0$011$1.60MOct 14, 2026
Kristen M. OelschlagerCOO0$07$1.77MOct 5, 2026
Frank StokesCFO0$01$742KAug 18, 2026

All trades

CSTL insider trades
FiledTradedInsiderRoleTypeSharesPrice ($)ValueHolding3 mo. afterFiling
Oct 21Oct 19Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-18,58031.91$274K−41%Form 4 ↗
Oct 21Oct 19Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-15,91631.91$189K−59%Form 4 ↗
Oct 14Oct 12Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-13,28833.64$111K−6.3%Form 4 ↗
Oct 7Oct 5Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-18,58035.57$305K−29%Form 4 ↗
Oct 7Oct 5Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-15,91635.57$210K−46%Form 4 ↗
Oct 5Oct 1Kristen M. OelschlagerCOOCOO▼ SELL10b5-14,15335.95$149K−24%Form 4 ↗
Oct 1Sep 29Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-15,54335.50$197K−9.5%Form 4 ↗
Oct 1Sep 30Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-11,03434.20$35K−1.9%Form 4 ↗
Sep 23Sep 21Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-18,58035.33$303K−29%Form 4 ↗
Sep 23Sep 21Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-15,91635.33$209K−38%Form 4 ↗
Sep 16Sep 15Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-13,29435.14$116K−5.3%Form 4 ↗
Sep 16Sep 14Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-13,30632.32$107K−5.1%Form 4 ↗
Sep 15Sep 11Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-18,58432.02$275K−29%Form 4 ↗
Sep 15Sep 11Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-15,93432.02$190K−33%Form 4 ↗
Sep 3Sep 1Kristen M. OelschlagerCOOCOO▼ SELL10b5-14,15233.39$139K−24%Form 4 ↗
Sep 2Aug 31Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-11,73032.81$57K−2.6%Form 4 ↗
Sep 1Aug 28Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-112,42833.20$413K−37%Form 4 ↗
Sep 1Aug 28Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-16,13233.20$204K−26%Form 4 ↗
Aug 27Aug 25Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-19,05035.04$317K−12%Form 4 ↗
Aug 26Aug 25Kristen M. OelschlagerCOOCOO (ind.)▼ SELL12,38434.42$426K−15%Form 4 ↗
Aug 26Aug 24Kristen M. OelschlagerCOOCOO (ind.)▼ SELL12,21833.69$412K−13%Form 4 ↗
Aug 19Aug 17Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-11,73029.59$51K−2.2%Form 4 ↗
Aug 18Aug 14Frank StokesCFOCFO▼ SELL24,90829.77$742K−42%Form 4 ↗
Aug 18Aug 14Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-16,13230.02$184K−35%Form 4 ↗
Aug 18Aug 14Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-11,10030.02$33K−4.9%Form 4 ↗
Aug 6Aug 4Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-120,35631.11$633K−49%Form 4 ↗
Aug 6Aug 4Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-115,08531.11$469K−43%Form 4 ↗
Aug 6Aug 5Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-12,54630.68$78K−11%Form 4 ↗
Aug 6Nov 24Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-11,30138.39$50K−1.6%Form 4 ↗
Aug 6Aug 5Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-11,02930.68$32K−4.3%Form 4 ↗
Aug 5Aug 3Kristen M. OelschlagerCOOCOO▼ SELL10b5-18,58629.77$256K−39%Form 4 ↗
Aug 4Jul 31Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-117,31029.31$507K−18%Form 4 ↗
Aug 4Aug 3Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-110,66430.35$324K−33%Form 4 ↗
Aug 4Aug 3Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-17,82930.35$238K−23%Form 4 ↗
Aug 4Jul 31Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-16,48030.15$195K−23%Form 4 ↗
Aug 4Jul 31Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-13,67330.15$111K−11%Form 4 ↗
Aug 4Aug 3Tobin W. JuvenalChief Commercial OfficerChief Commercial Officer▼ SELL10b5-11,73028.25$49K−2.1%Form 4 ↗
Jul 29Jul 27Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-16,21424.16$150K−22%Form 4 ↗
Jul 29Jul 27Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-13,62224.16$88K−8.7%Form 4 ↗
Jul 16Jul 14Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-13,62222.92$83K−23%Form 4 ↗
Jul 16Jul 14Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-155022.92$13K−2.5%Form 4 ↗
Jul 6Jul 1Kristen M. OelschlagerCOOCOO▼ SELL10b5-18,58624.42$210K−28%Form 4 ↗
Jul 6Jul 1Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-16,21424.29$151K−22%Form 4 ↗
Jul 6Jul 1Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-13,62224.29$88K−23%Form 4 ↗
Jun 18Jun 16Kristen M. OelschlagerCOOCOO▼ SELL10b5-18,58720.71$178K−22%Form 4 ↗
Jun 17Jun 15Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer (ind.)▼ SELL10b5-13,62220.66$75K−22%Form 4 ↗
Jun 17Jun 15Derek J. MaetzoldPres. & Chief Exec. OfficerPres. & Chief Exec. Officer▼ SELL10b5-155020.66$11K−2.5%Form 4 ↗
Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings