Is CSTL diluting shareholders?

Read three numbers together: shares outstanding over time (30.5M as of 2026-07-23), warrants that can convert into new shares (0 reported), and how much cash runway remains. A company short on cash with live registrations is structurally likely to issue shares.

Where do these numbers come from?

SEC EDGAR only: the XBRL company-facts API for shares, warrants and cash, and filing metadata for registrations and pricings. Every figure shows its source form, and nothing here is estimated by us beyond the arithmetic stated next to it.

Why might a warrant tranche be missing from the table?

The tranche table is built from the dimensions the company tagged in its own 10-Q or 10-K XBRL. A tranche the filer chose not to dimension does not appear, and its absence proves nothing: the exhibits remain the ground truth. Everything shown carries the filing it came from.

Dilution profile // every instrument, one screen, from SEC filings

CASTLE BIOSCIENCES INC (CSTL)

CIK 1447362 · all EDGAR filings →

Overall dilution risk

HIGHworst of 4 computed signals (offering ability)

= the worst band among the computed sub-ratings, no hidden weighting

Offering ability

HIGHS-3 on file 2024-02-28

= is there a registration (S-1/S-3 family) on file without a later withdrawal

no structured fee data on the live registrations, so this is a yes/no, not a size

Overhead supply

LOWwarrants = 0% of O/S

= warrant shares outstanding divided by current shares outstanding (bands: 20% / 50%)

warrants only; converts, ATMs and equity lines are not in free structured data, so the true overhead is AT LEAST this

Historical dilution

LOW+14% O/S in 3y

= share count now vs 3 years ago (bands: 30% / 100%); a reverse split pushes this negative

Cash need

LOWoperating cash flow positive

= cash vs trailing operating burn (bands: 6mo / 24mo; positive operating CF = low)

the company itself flagged going-concern doubt

Same rating bands the category standard uses, but free, with the formula on the chip and the gaps in the data said out loud.

Shares outstanding over time

Latest: 30.5M shares as of Jul 23, 2026 (10-Q).

Cash runway

Going-concern warning

auditor flagged substantial doubt

The company itself flagged going-concern doubt in a filing.

Full breakdown: cash runway tool · source filing →

Warrants

Warrants outstanding: 0 underlying shares, as reported Dec 31, 2021 (10-K).

Balance-sheet fair value of warrants: $0 as of Dec 31, 2019.

Rough fully diluted estimate: 30.5M = 30.5M O/S + 0 warrant shares. An estimate, not a filing figure: it ignores converts, options and RSUs, and the two inputs carry different as-of dates.

Convertible notes

No convertible-note facts tagged in the 10-Q filed Jul 30, 2026. If convertible notes exist, their terms live in exhibit prose for this filer and are not parsed; absence of a tag is not proof of absence. The exhibits are the ground truth.

Fully diluted build-up

Shares outstanding plus every potential-share instrument the filer tagged in XBRL, each at its own as-of date. An estimate assembled from filed figures, not a filing figure itself.

Shares outstanding	30.5M	Jul 23, 2026
+ Warrants (aggregate, as tagged) (if exercised)	0	Dec 31, 2021
Fully diluted estimate	30.5M	+0.0% vs O/S

Still excluded, because the filer does not tag them in countable form: employee options and RSUs, any instrument living only in exhibit prose, and instruments above missing a share count. Inputs carry different as-of dates, shown per row. Each figure traces to the tranche and note tables above and their cited filings.

Registrations and offerings

S-3Feb 28, 2024no structured fee exhibit in this filing (predates fee-data XBRL or fee deferred)filing →

Last 12 months: 0 executed · 0 registered.

EFFECTIVEApr 16, 2024SEC declared a registration effective — selling can beginEFFECT →

REGISTEREDFeb 28, 2024S-3 registration — capacity to sell shares, not a sale yetS-3 →

REGISTEREDJun 6, 2022Automatic shelf registration — effective immediately (large filers)S-3ASR →

EXECUTEDMay 2, 2022Unregistered share sale disclosed (8-K item 3.02)8-K →

EXECUTEDApr 4, 2022Unregistered share sale disclosed (8-K item 3.02)8-K →

REGISTEREDJan 14, 2022Automatic shelf registration — effective immediately (large filers)S-3ASR →

EXECUTEDDec 16, 2020Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)424B5 →

REGISTEREDDec 14, 2020Automatic shelf registration — effective immediately (large filers)S-3ASR →

EXECUTEDDec 14, 2020Shelf takedown priced — shares or notes (small-caps: usually shares; open the filing to confirm)424B5 →

EXECUTEDJun 25, 2020Final prospectus — offering priced (typical for IPOs and marketed share deals)424B4 →

REGISTEREDJun 24, 2020S-1MEF registration — capacity to sell shares, not a sale yetS-1MEF →

EFFECTIVEJun 24, 2020SEC declared a registration effective — selling can beginEFFECT →

Full history and shelf status: offering checker · S-3 shelf checker

Source: SEC EDGAR XBRL company facts and filing metadata, fetched live and cached briefly. Share counts are cover-page figures with their form named. Warrant tranches and convertible notes come from the dimensioned facts in the latest 10-Q/10-K instance document, exactly as the company tagged them; untagged tranches and notes are absent, not disproven. Nothing on this page is manually verified and nothing is behind a login: what free data supports is shown, what it cannot support is stated. Not investment advice.

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