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CSTL Insider Trading and Fund Holdings (CASTLE BIOSCIENCES INC) · https://wallstpal.com/stock/cstl/ · 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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StockCIK 1447362

CASTLE BIOSCIENCES INC (CSTL): Insider Trades and Fund Holdings

In the past 12 months, CASTLE BIOSCIENCES INC insiders reported no open-market purchases and 47 sales worth $9.63M; 44 of the sales were reported as made under a 10b5-1 trading plan.

0Insider buys, 12 months
$0Bought by insiders, 12 months
$9.63MSold by insiders, 12 months
1Tracked funds holding

Timeline: news and trades

Company filings (8-K), insider trades, notices of planned sales (Form 144), Congress trades and fund moves in the past year, newest first.

  1. Oct 19, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $462,567 under a 10b5-1 plan
  2. Oct 13, 2026Planned saleTobin Juvenal (chief commercial officer) filed notice to sell about $430,925 around Oct 12, 2026
  3. Oct 12, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $110,608 under a 10b5-1 plan
  4. Oct 5, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $515,564 under a 10b5-1 plan
  5. Oct 5, 2026Planned saleDerek Maetzold (officer) filed notice to sell about $1.1 million around Oct 5, 2026
  6. Oct 1, 2026Insider saleCOO Kristen M. Oelschlager sold $149,317 under a 10b5-1 plan
  7. Oct 1, 2026Planned saleKRISTEN OELSCHLAGER (officer) filed notice to sell about $147,556 around Oct 1, 2026
  8. Sep 30, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $35,363 under a 10b5-1 plan
  9. Sep 29, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $196,765 under a 10b5-1 plan
  10. Sep 21, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $512,202 under a 10b5-1 plan
  11. Sep 15, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $115,758 under a 10b5-1 plan
  12. Sep 14, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $106,863 under a 10b5-1 plan
  13. Sep 14, 2026Planned saleTobin Juvenal (chief commercial officer) filed notice to sell about $440,639 around Sep 14, 2026
  14. Sep 11, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $464,870 under a 10b5-1 plan
  15. Sep 11, 2026Planned saleDerek Maetzold (officer) filed notice to sell about $938,023 around Sep 11, 2026
  16. Sep 1, 2026Insider saleCOO Kristen M. Oelschlager sold $138,643 under a 10b5-1 plan
  17. Aug 31, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $56,761 under a 10b5-1 plan
  18. Aug 28, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $616,132 under a 10b5-1 plan
  19. Aug 25, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $317,112 under a 10b5-1 plan
  20. Aug 25, 2026Insider saleCOO Kristen M. Oelschlager sold $426,276
  21. Aug 25, 2026Planned saleTobin Juvenal (chief commercial officer) filed notice to sell about $787,500 around Aug 25, 2026
  22. Aug 24, 2026Insider saleCOO Kristen M. Oelschlager sold $411,588
  23. Aug 24, 2026Planned saleKristen M. Oelschlager (officer) filed notice to sell about $841,388 around Aug 24, 2026
  24. Aug 17, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $51,191 under a 10b5-1 plan
  25. Aug 14, 2026Insider saleCFO Frank Stokes sold $741,511
  26. Aug 14, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $217,106 under a 10b5-1 plan
  27. Aug 14, 2026Planned saleDerek Maetzold (officer) filed notice to sell about $763,959 around Aug 14, 2026
  28. Aug 14, 2026Planned saleFRANKLIN M. STOKES (officer) filed notice to sell about $741,494 around Aug 14, 2026
  29. Aug 5, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $109,685 under a 10b5-1 plan (6 days after: quarterly or annual results)
  30. Aug 4, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $1.1 million under a 10b5-1 plan (5 days after: quarterly or annual results)
  31. Aug 3, 2026Insider saleCOO Kristen M. Oelschlager sold $255,622 under a 10b5-1 plan (4 days after: quarterly or annual results)
  32. Aug 3, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $561,318 under a 10b5-1 plan (4 days after: quarterly or annual results)
  33. Aug 3, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $48,873 under a 10b5-1 plan (4 days after: quarterly or annual results)
  34. Jul 31, 2026Insider saleChief Commercial Officer Tobin W. Juvenal sold $507,301 under a 10b5-1 plan (1 days after: quarterly or annual results)
  35. Jul 31, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $306,133 under a 10b5-1 plan (1 days after: quarterly or annual results)
  36. Jul 31, 2026Planned saleDerek Maetzold (officer) filed notice to sell about $1.9 million around Jul 31, 2026
  37. Jul 31, 2026Planned saleTobin Juvenal (chief commercial officer) filed notice to sell about $630,000 around Jul 31, 2026
  38. Jul 30, 2026NewsCompany reported: Quarterly or annual results
  39. Jul 27, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $237,685 under a 10b5-1 plan
  40. Jul 14, 2026Insider salePres. & Chief Exec. Officer Derek J. Maetzold sold $95,623 under a 10b5-1 plan

Showing the latest 40 of 46 events.

Recent insider trades

Open-market purchases (code P) and sales (code S) from Form 4. Grants, option exercises and gifts are not shown. Latest filing: Oct 21, 2026.

Recent CSTL insider trades
FiledTradedInsiderRoleTypeSharesPrice ($)ValueHoldingFiling
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 ↗
Source: SEC Form 4 filings, retrieved Oct 28, 2026. How we read filings
All 47 CSTL insider trades →

Insiders who traded in the past year

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

Buybacks and executive pay

YearCEO pay reportedCEO pay "actually paid"Value of $100 invested
2025$6.79M$13.2Mn/a
2024$6.94M$9.97Mn/a
2023$1.61M$780Kn/a

From the company's XBRL data filed with the SEC. "Actually paid" is the SEC's pay-versus-performance measure, which counts changes in the value of stock awards. "Value of $100 invested" is the company's cumulative shareholder return as reported, usually measured from five years earlier. See all buybacks and CEO pay across companies.

Filing quality

A 1 of 47 insider trades reported after the deadline. How it is graded

Tracked funds that report CSTL

From each fund's latest 13F. Holdings are as of quarter end and are filed up to 45 days later.

FundQuarterSharesValue% of portfolioChange
Renaissance TechnologiesQ2 2026371,200$8.85M0.01%▼ −30.3%
Source: SEC Form 13F-HR filings, retrieved Oct 28, 2026. How we read filings

Reading these numbers

Insiders sell for many reasons: taxes, diversification, a house. Purchases with their own money are rarer and are usually read as more informative. A Form 4 is due within two business days of the trade. How to read a Form 4 →