261 transactions on file (0 open-market purchases and 197 open-market sales).
197 open-market sales by CSTL insiders, between Sep 17, 2025 and Sep 1, 2026. A sale made under a trading plan agreed months earlier is not the same event as one decided that week, and the filing itself says which.
Discretionary. The box was on the form and was not ticked. The sale was made at the prevailing price without a pre-arranged plan behind it.
Planned (10b5-1). The filer ticked the Form 4's 10b5-1 box: the sale ran under a trading plan adopted before the trade, so it is a schedule executing rather than a view taken this week.
Not stated. The filing does not say. Either it predates the April 2023 checkbox, or nothing has re-read it since. This tab will not guess which of the two above it was.
| Date | Insider | Type | Shares | Price | Value | Owned after |
|---|---|---|---|---|---|---|
| 2026-09-01 | Oelschlager Kristen M Chief Operating Officer Option exercise | Option exercise | +4,152 | $3.38 | +14.03K | 17,508 |
| 2026-09-01 | Oelschlager Kristen M Chief Operating Officer Open-market salePlanned (10b5-1) | Open-market sale Planned (10b5-1) | −200 | $34.02 | −6.8K | 13,356 |
| 2026-09-01 | Oelschlager Kristen M Chief Operating Officer Open-market salePlanned (10b5-1) | Open-market sale Planned (10b5-1) | −3,952 | $33.36 | −131.84K | 13,556 |
| 2026-08-31 | Juvenal Tobin W Chief Commercial Officer Open-market salePlanned (10b5-1) | Open-market sale Planned (10b5-1) | −1,730 | $32.81 | −56.76K | 65,184 |
| 2026-08-28 | MAETZOLD DEREK J Pres. & Chief Exec. Officer · Director Option exercise | Option exercise | +12,428 | $2.39 | +29.7K | 33,907 |
256 more transactions are on Measure
| Insider | Role | On Sep 11, 2025 | Now | Change | Sold | Shape |
|---|---|---|---|---|---|---|
| MAETZOLD DEREK JPres. & Chief Exec. Officer, Director | Pres. & Chief Exec. Officer, Director | 67,005 | 11,256 | −83.20% | $9.75M$9.75M on a plan | |
| Oelschlager Kristen MChief Operating Officer | Chief Operating Officer | 40,247 | 13,356 | −66.81% | $3.19M$1.42M no plan · $1.76M on a plan | |
| Stokes FrankChief Financial Officer | Chief Financial Officer | 48,716 | 35,177 | −27.79% | $1.46M$909.89K no plan · $548.99K on a plan |
The assistant answers from what CSTL has actually filed: 8 annual reports filed with the SEC, 200 Form 4 filings from the last year and 3 funds that hold it. Every figure in a reply links to the filing it came from, so an answer can be checked rather than believed.
Pressing one answers it here, from CSTL's filings and figures. One a day without an account; a free account has its own, and no card.
See every Form 4 CSTL insiders have filed, not the latest few.
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Source
From SEC Form 4 filings, filed by officers, directors and 10%-owners within two business days of a transaction. “Indirect” holdings (a trust, an LLC, a family member) are included and not distinguished from direct ones in this table.
Past transactions say nothing about future ones, and none of this is investment advice.
2 more insiders, included withMeasure
Each person’s holding as they reported it after each open-market trade, over the last twelve months. It counts one class of stock and excludes grants, option exercises and shares withheld for tax, so a stake can fall here while somebody’s total holding does not. Since April 2023 a Form 4 states whether a trade ran under a pre-arranged 10b5-1 plan; an older one does not, and those dollars read “not stated” rather than being counted either way.
See who bought, not who was handed shares
Every Form 4 CSTL insiders file, not just the latest handful, with vesting and tax withholding struck out so what's left reads as a decision.
Every filingMeasure
Follow the investors who hold it
Each stake priced at the quarter it was filed, and diffed against the quarter before: who added, who trimmed, who left.
Every position they holdMeasure
Ask what a run of filings adds up to
Whether this is one decision or a pattern, and how it compares with CSTL's own history of insider activity.
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