Castle Biosciences (CSTL)
Provides clinician-facing molecular diagnostic tests across dermatology and gastroenterology.
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Develops and commercializes molecular diagnostic tests for dermatologic cancers, Barrett’s esophagus, uveal melanoma, and atopic dermatitis. Its portfolio grew from dermatologic testing through internal development and targeted acquisitions.
Develops and commercializes molecular diagnostic tests that help clinicians manage dermatologic cancers, Barrett’s esophagus, uveal melanoma, and atopic dermatitis. DecisionDx-Melanoma is a core gene-expression test, alongside DecisionDx-SCC, DecisionDx-UM, MyPath Melanoma, TissueCypher, and limited-access AdvanceAD-Tx.
The portfolio began in dermatologic molecular diagnostics and expanded through internal development and targeted acquisitions. Its original franchise was dermatologic molecular diagnostics. The company remains led by its founder. It serves clinician-facing dermatology and gastroenterology settings.
Revenue depends on laboratory operations, clinician adoption, and third-party payer reimbursement, including Medicare coverage. Medicare coverage for DecisionDx-SCC was discontinued.
Company facts
Target rangeAs of Sep 21, 2026
Latest analyst notes
| Date | Firm | Action | Prior | Current |
|---|---|---|---|---|
| Aug 3, 2026 | BTIG | Reiterate | Rating: —Target: $50 | Target: $44 |
| Jul 31, 2026 | Robert W. Baird | Target | Target: $37 | Target: $36 |
| Jun 24, 2026 | Roth Capital | Initiate | Rating: —Target: — | Target: $40 |
| May 29, 2026 | KeyBanc | Target | Target: $50 | Target: $35 |
| Apr 20, 2026 | Canaccord Genuity | Reiterate | Rating: —Target: $50 | Target: $40 |
EPSReportedEstimate
RevenueReportedEstimate
Balance sheet, Jun 30, 2026Cash & short-term investments $266.8M · Total debt $36.7M · Total assets $561.2M · Shareholders' equity $470.0M
- Revenue
- $103.5M
- Operating income
- −$3.1M
- Net income
- −$2.1M
No dividends on record.
| Institutions | 90.62% | 27.68M shares | |
|---|---|---|---|
| 180 holders · as of Jun 30, 2026 | |||
| Insiders | 5.49% | 1.68M shares | |
| 12 holders · as of Sep 16, 2026 | |||
| Other | 3.89% | 1.19M shares | |
| remainder | |||
30.55M company shares as of Sep 22, 2026 · institutions as of Jun 30, 2026 · holders as of their latest filing
Top shareholders13F · 13D/G · Form 4
| Holder | Stake | Shares | Date |
|---|---|---|---|
BlackRock, Inc.Institution | 10.78% | 3.29M | as of Jun 30, 2026 |
RTW Investments, LPInstitution | 9.09% | 2.78M | as of Jun 30, 2026 |
ARK Investment Management LLCInstitution | 8.36% | 2.55M | filed Feb 10, 2021 |
Granahan Investment Management LLCInstitution | 7.09% | 2.17M | filed Feb 14, 2024 |
Principal Financial Group IncInstitution | 5.65% | 1.73M | as of Jun 30, 2026 |
Insider tradesForm 4
| Date | Insider | Role | Shares | Avg price |
|---|---|---|---|---|
| Sep 15, 2026 | Tobin W. Juvenal | officer: Chief Commercial Officer | −3,294 | $35.14 |
| Sep 14, 2026 | Tobin W. Juvenal | officer: Chief Commercial Officer | −3,306 | $32.32 |
| Sep 11, 2026 | Derek J. Maetzold | director, officer: Pres. & Chief Exec. Officer | −14,518 | $32.02 |
| Sep 1, 2026 | Kristen M. Oelschlager | officer: Chief Operating Officer | −4,152 | $33.39 |
| Aug 31, 2026 | Tobin W. Juvenal | officer: Chief Commercial Officer | −1,730 | $32.81 |
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Compare
| Company | Price | Change | |||||
|---|---|---|---|---|---|---|---|
| Castle Biosciences | $35.03 | +0.11% | $1.07B | — | — | 3.0 | +20.1% |
| Quest Diagnostics | $235.34 | −3.90% | $27.03B | 26.0 | 20.5 | 2.3 | +10.2% |
| Tempus AI | $76.86 | −1.50% | $13.67B | — | — | 9.5 | +21.6% |
| Lucid Diagnostics | $0.8951 | +5.91% | $161.2M | — | — | 29.6 | +26.7% |
| NeoGenomics | $18.91 | −2.58% | $498.7M | — | 68.0 | 0.7 | +11.2% |
| Median | 26.0 | 44.3 | 5.9 | +16.4% |