---
schema_version: "secwatch.filing_event.v1"
accession: "0001447362-24-000059"
form_type: "8-K"
ticker: "CSTL"
cik: "0001447362"
company_name: "CASTLE BIOSCIENCES INC"
filed_at: "2024-05-02T23:59:59+00:00"
generated_at: "2026-06-03T00:17:34.680868+00:00"
event_type: "earnings"
sentiment: "positive"
materiality_score: 0.8
calibrated_materiality_score: 0.8
confidence: "high"
source: SEC EDGAR
---

# Castle Biosciences Q1 revenue $73M (+74% YoY); raises FY2024 guidance to $255-265M

## Summary
- Q1 revenue $73.0M (+74% YoY); adjusted revenue $71.3M (+64% YoY).
- Net loss narrowed to $2.5M from $29.2M; adjusted EBITDA improved to $10.5M from -$15.1M.
- Total test reports +40% to 20,888; TissueCypher +148%, IDgenetix +90%.
- FY2024 revenue guidance raised to $255-265M from prior $235-240M.
- Cash & marketable securities $239.2M; gross margin 78% (adj. 81%).

## SEC filing metadata
- accession: 0001447362-24-000059
- form_type: 8-K
- ticker: CSTL
- cik: 0001447362
- company_name: CASTLE BIOSCIENCES INC
- filed_at: 2024-05-02T23:59:59+00:00
- event_type: earnings
- sentiment: positive
- materiality_score: 0.8
- calibrated_materiality_score: 0.8
- confidence: high
- sec_items: 2.02, 7.01, 9.01
- EDGAR index: https://www.sec.gov/Archives/edgar/data/1447362/000144736224000059/0001447362-24-000059-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/1447362/000144736224000059/cstl-20240502.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0001447362-24-000059
- JSON: https://secwatch.observer/filing/0001447362-24-000059.json
- Plain text: https://secwatch.observer/filing/0001447362-24-000059.txt

## Key facts
- Earnings Releases
  CASTLE BIOSCIENCES INC reported the first quarter ended March 31, 2024 results: revenue $73.0 million, net income Net loss... was $2.5 million. Guidance raised.
  - Period: the first quarter ended March 31, 2024
  - Revenue: $73.0 million
  - Net income: Net loss... was $2.5 million
  - Guidance: raised
  - Result: reported results
  source text: such filing to this Current Report on Form 8-K. --- EX-99.1 (EX-99.1) --- Castle Biosciences Reports First Quarter 2024 Results Q1 2024 revenue increased 74% over Q1 2023 to $73 million Q1 2024 total test reports increased 40% over Q1 2023 Raising full-year 2024 revenue guidance to $ 255-265 million from $235-240 million Conference call and webcast today at 4:30
  evidence_url: https://www.sec.gov/Archives/edgar/data/1447362/000144736224000059/0001447362-24-000059-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.