Insider transactions

DEREK J MAETZOLD

CIK 1239501 · Pres. & Chief Exec. Officer · last filed 2026-09-23

DEREK J MAETZOLD is a Pres. & Chief Exec. Officer who has filed 232 SEC Form 4 insider transactions across 2 companies since 2007. The most recent filing, for CSTL, was dated Sep 23, 2026. Across all open-market trades the lifetime net is −$96.9M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $2.2M across reported positions.

"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.

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Disclosed Exposure

$2.22M

Companies

2

Total Filings

232

Lifetime Open-Market Net

-$96.89M

Charts

Trading activity, where the exposure sits, and each trade against the stock price.

Filer Profile

Reported Address
820 S. FRIENDSWOOD DRIVE
SUITE 201
FRIENDSWOOD, TX 77546
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

Holdings By Company

Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
Symbol Role Shares Price Disclosed Exposure Lifetime OM Net Filings Latest Filed
CSTL Pres. & Chief Exec. Officer 62,414 $35.49 $2.22M -$96.89M 196 2026-09-23
ENCYSIVE PHARMACEUTICALS INC (ENCY) Delisted V.P., Marketing & Sales 0 — — $0 4 2008-04-03

Recent Filings

232 filings
Insider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
Filed Symbol Action Net Shares Net $ Link
2026-09-23 CSTL Mixed −5,916 -$491.7K EDGAR
2026-09-15 CSTL Mixed −5,934 -$444.4K EDGAR
2026-09-11 CSTL Notice (144) −29,014 -$938.0K EDGAR
2026-09-01 CSTL Mixed −6,132 -$586.4K EDGAR
2026-08-18 CSTL Mixed −6,132 -$214.5K EDGAR
2026-08-14 CSTL Notice (144) −25,792 -$764.0K EDGAR
2026-08-06 CSTL Mixed −16,114 -$1.16M EDGAR
2026-08-06 CSTL Mixed −16,114 -$1.16M EDGAR
2026-08-04 CSTL Mixed −11,502 -$826.5K EDGAR
2026-07-31 CSTL Notice (144) −67,662 -$1.89M EDGAR
Showing 1–10 of 232
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Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.