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CASTLE BIOSCIENCES INC (CSTL)

Institutional ownership, SEC filings and insider activity

Sector: Healthcare & Pharma · SEC CIK 0001447362 · EDGAR filings · Updated 2026-07-16

CASTLE BIOSCIENCES INC (CSTL) has reported institutional ownership of 91.0%, with 187 institutional managers holding positions valued at $677.8M per the latest 13F reporting period. SEC filings include an active substantial-doubt (going concern) disclosure per the filings, triggering event that accelerates or increases a direct financial obligation (8-K Item 2.04).

Latest updates

• 2026-07-16 — Insider transaction reported (Form 4)
• 2026-07-06 — Insider transaction reported (Form 4)
• 2026-07-06 — Insider transaction reported (Form 4)
• 2026-07-01 — Notice of proposed sale filed (Form 144)
• 2026-06-18 — Insider transaction reported (Form 4)
• 2026-06-17 — Insider transaction reported (Form 4)

Institutional ownership overview

According to SEC 13F filings tracked by Sightfile, CASTLE BIOSCIENCES INC has 187 institutional holders and institutional ownership of 91.0%.

Insider activity

Insiders reported 148 transactions (0 buys, 93 sells) across 11 reporting insiders, with a net reported value of −$11.7M.

Data flags from SEC filings

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