§ HEALTH CARE
USD · Health CareCSTL
CASTLE BIOSCIENCES INC
USDSector · Health CareBeta · 1.02
§ 01 · PRICE
Price action
1D5D1M6MYTD1YMAX
§ 03 · SIGNAL STACK · WHAT THE INPUTS SAY
13F FLOW
103 increased/new, 60 decreased/exited (13F)
AC 13F Analysis
§ 04 · FUNDAMENTALS · THE BOOKS
| P/B | 2.41 | EPS (TTM) | -0.43 |
§ 05 · WHO OWNS IT
Top institutional holders
| Fund | Shares | % port | Δ Q/Q |
|---|---|---|---|
| BlackRock, Inc. | 3.0M | 0.0% | −4% |
| RTW INVESTMENTS, LP | 2.8M | 0.7% | +30% |
| PRINCIPAL FINANCIAL GROUP INC | 1.8M | 0.0% | −2% |
| Portolan Capital Management, LLC | 1.4M | 1.8% | −22% |
| VANGUARD CAPITAL MANAGEMENT LLC | 1.2M | n/a | n/a |
| Dimensional Fund Advisors | 1.0M | 0.0% | −9% |
◇ AC INTELLIGENCE
Top institutional owners for CSTL as of the most recent 13F reporting period (Q1 2026 · Period ended Mar 31). Δ Q/Q reflects share-count change vs. the prior filing — positive green means adding, negative red means trimming. Cross-reference with the ownership-mix bars below to see which strategy cohort is driving the flow.
§ 06 · WHO OWNS IT · BY STRATEGY
OTHER96.1% · 0 holders
OTHER2.1% · 129 holders
PASSIVE / INDEX0.6% · 7 holders
QUALITY / COMPOUNDER0.4% · 15 holders
DEALER / BANK0.3% · 22 holders
INCOME / DEFENSIVE0.3% · 6 holders
TACTICAL / MACRO0.1% · 3 holders
SYSTEMATIC / QUANT0.1% · 6 holders
ACTIVIST0.0% · 1 holder
◇ AC INTELLIGENCE
Ownership mix by behavioral cohort. Top bars indicate which style of capital dominates the float — passive indexing, quality compounders, dealer/bank, systematic quant, etc. Big quality-compounder share means concentrated active conviction; heavy passive share means flows are dictated by index rebalances, not fundamentals.
§ 07 · INSIDER ACTIVITY · LAST 180 DAYS
NO INSIDER FILINGS
◇ AC INTELLIGENCE
No Form 4 filings on record for CSTL in the last 180 days.
§ 08 · COVERAGE · OUR RECENT NOTES
No notes mention CSTL yet.