Castle Biosciences
Castle Biosciences is a publicly traded molecular diagnostics company that develops gene expression profiling and AI-driven spatialomics tests for cancer prognosis, diagnosis, and therapy guidance, serving dermatologists, gastroenterologists, and ophthalmologists across the United States.
- Company typePublic
- Founded2008
- HeadquartersFriendswood, United States
- Headcount501–1,000
- GTM typeB2B
- OfferingServices
What Castle Biosciences does
Castle Biosciences, Inc. is a publicly traded (NASDAQ: CSTL) molecular diagnostics company founded in 2008 by Derek J. Maetzold and headquartered in Friendswood, Texas. The company develops and commercializes proprietary gene expression profiling (GEP) tests and AI-driven spatialomics assays that provide prognostic, diagnostic, and therapy-guidance information for cancer and inflammatory skin disease. Its core technology platform uses qRT-PCR-based gene expression measurement and an AI-derived spatialomics classifier, with proprietary assays including a 31-gene profile (DecisionDx-Melanoma), 40-gene profile (DecisionDx-SCC), 15-gene profile (DecisionDx-UM), and 487-gene profile (AdvanceAD-Tx), alongside the TissueCypher AI spatialomics test for Barrett's esophagus. All testing is processed in the company's CAP-accredited, CLIA-certified laboratory, with results delivered through a secure clinician portal.
The company generates revenue by performing laboratory diagnostic tests ordered by healthcare providers, which are billed to insurance payers including Medicare, Medicaid, commercial insurers, and the Veterans Affairs system. Castle distributes its tests via a domestic direct sales force of area managers targeting dermatologists, gastroenterologists, and ophthalmologists, supplemented by an online clinician portal and fax-based ordering. Cumulative volume exceeds 300,000 test reports since 2008, including 220,000+ DecisionDx-Melanoma orders, 100,000+ TissueCypher orders (June 2026), and adoption by 3,000+ clinicians for TissueCypher alone. Full-year 2025 revenue was $344.2 million (4% year-over-year growth), with Q1 2026 revenue of $83.7 million and 36% year-over-year growth in core test report volumes; management has guided full-year 2026 revenue to $345–355 million.
Castle has built its portfolio through an aggressive inorganic strategy, acquiring Myriad myPath (2021, $32.5M), Cernostics (2021, up to $80M), AltheaDx (2022, $65M plus up to $75M earn-out), and Previse (2025), and recently opened a new 23-acre purpose-built headquarters in March 2026 to support a workforce of approximately 800 employees. The customer base is highly fragmented across U.S. specialty practices, with named research collaborators including Mayo Clinic, and the company has not pursued international commercialization.
Castle Biosciences firmographics
Firmographics- Name
- Castle Biosciences
- Legal name
- Castle Biosciences, Inc.
- Website
- https://castlebiosciences.com
- Company type
- Public
- Founded year
- 2008
- Operating status
- Operating
- Headcount range
- 501–1,000 employees
- Short description
- Castle Biosciences is a publicly traded molecular diagnostics company that develops gene expression profiling and AI-driven spatialomics tests for cancer prognosis, diagnosis, and therapy guidance, serving dermatologists, gastroenterologists, and ophthalmologists across the United States.
- Ownership category
- akta.pro rank
Castle Biosciences industry classification
Industry- Product category
- Molecular Diagnostics
- NAICS
- Medical Laboratories (621511)
- SIC
- Services-Medical Laboratories (8071)
- akta.pro primary industry
- Molecular & Genetic Testing (PCR/NGS/qPCR) (HLAGADAF)
- akta.pro secondary industries
- Oncology Diagnostics (tumor profiling, MRD, liquid biopsy) (HLAAALAE), Laboratory Developed Tests (LDTs) & Specialized Clinical Lab Assays (HLAAALAN), Clinical Biomarker Testing Services (central labs, trial enrollment/monitoring assays) (HLAAAMAC)
Keywords
Where Castle Biosciences is headquartered
LocationHeadquarters
- HQ city
- Friendswood
- HQ country
- United States
- HQ region
- North America
Offices2 records
Markets served
Castle Biosciences business model
Business model- GTM type
- B2B
- Offering type
- Services
- Cost components
- Personnel, Technology or R&D, Marketing or Sales, Operations, Infrastructure
Revenue model
- Laboratory Diagnostic Testing Services: Castle Biosciences generates revenue primarily through providing molecular diagnostic and prognostic laboratory testing services. Tests are ordered by healthcare providers and billed to insurance (Medicare, Medicaid, commercial insurers, VA). The company operates a CAP-accredited, CLIA-certified laboratory.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Other | Pay-as-you-go | Laboratory testing services billed per test report |
Go-to-market motion1 record
Distribution channels3 records
Marketing channels6 records
Castle Biosciences product offering
Product offeringCore offering
Castle Biosciences develops and commercializes proprietary molecular diagnostic and prognostic tests that use gene expression profiling and AI-driven spatialomics to inform cancer and dermatologic disease management decisions. Tests are ordered by healthcare providers and processed in the company's CLIA-certified, CAP-accredited laboratory, with results delivered through a secure clinician portal. Core offerings include DecisionDx-Melanoma, DecisionDx-SCC, DecisionDx-UM, TissueCypher, MyPath Melanoma, AdvanceAD-Tx, and adjunct DecisionDx-PRAME and DecisionDx-UM*Seq* tests.
Product overview
Castle Biosciences operates as a molecular diagnostics company offering a portfolio of innovative gene expression profiling (GEP) tests across dermatology, gastroenterology, and ophthalmology. The product portfolio includes prognostic tests (DecisionDx-Melanoma for cutaneous melanoma recurrence risk, DecisionDx-SCC for squamous cell carcinoma metastasis risk, DecisionDx-UM for uveal melanoma metastasis risk, and TissueCypher for Barrett's esophagus cancer progression risk), diagnostic tests (MyPath Melanoma for differentiating melanoma from benign lesions), and therapy guidance tests (AdvanceAD-Tx for atopic dermatitis treatment selection). Additional offerings include DecisionDx-PRAME and DecisionDx-UM*Seq* as adjunct tests for uveal melanoma. Tests are processed in the company's CAP-accredited and CLIA-certified laboratory, with results delivered via secure online clinician portal.
Differentiator
Problem solved
Functional benefit
Brands
- DecisionDx-Melanoma: 31-gene expression profile test for cutaneous melanoma prognosis and SLNB decision guidance
- DecisionDx-SCC
- DecisionDx-UM
- TissueCypher
- MyPath Melanoma
- AdvanceAD-Tx
- DecisionDx-PRAME
- DecisionDx-UMSeq
Products and services
- DecisionDx-Melanoma
Quantifiable outcome
- TissueCypher test modified surveillance intervals in 55% of patients following testing (Mayo Clinic data at DDW 2026)
- +3 more outcomes
Companies that use Castle Biosciences
Customer profileNamed customers4 records
Segments4 records
Ideal customer profiles3 records
Castle Biosciences technology and API
TechnologyTechnology focussed Yes
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
AI capability4 records
Feature6 records
Castle Biosciences partnerships and signals
Strategic signalPartnerships
Six partnerships are on record, tiered core and minor.
- SciBasecoreCollaboration on DETECT-AD clinical study to assess Electrical Impedance Spectroscopy (EIS) technology for predicting flares in atopic dermatitis patients. Castle Biosciences expanded collaboration with license and loan agreement (SEK 20 million) to accelerate development and production of skin diagnostic tests. SciBase is a medical technology company specializing in dermatology diagnostics with FDA-approved Nevisense device for melanoma detection.
- PrevisecoreCastle Biosciences acquired Previse in 2025 to expand its GI franchise and strengthen capabilities in gastroenterological disease diagnostics.
- AltheaDxcoreCastle Biosciences acquired AltheaDx in April 2022 for $65 million initial consideration (plus $75 million contingent on milestones) to expand into pharmacogenomics testing for mental health conditions. AltheaDx specializes in the IDgenetix test for personalized mental health treatment guidance.
- CernosticscoreCastle Biosciences acquired Cernostics in late 2021 for up to $80 million to expand into spatial biology and AI-driven tissue analysis for esophageal cancer diagnostics. Cernostics was a portfolio company of Pittsburgh Life Sciences Greenhouse.
- Myriad myPath, LLCcoreCastle Biosciences acquired Myriad myPath, LLC from Myriad Genetics in May 2021 for $32.5 million in cash, adding MyPath Melanoma diagnostic test to its portfolio.
- Patient Advocacy OrganizationsminorCastle partners with multiple patient-focused organizations including AIM at Melanoma, Melanoma Research Foundation, The Skin Cancer Foundation, IMPACT Melanoma, Nevada Cancer Coalition and The Sun Bus for patient education, advocacy walks, and skin cancer screening initiatives during Skin Cancer Awareness Month.
Scale indicators8 records
Recent moves7 records
Expansion highlights7 records
Castle Biosciences competitors and assessment
Company assessmentDirect peers
- Myriad Genetics: Oncology molecular diagnostics leader offering hereditary cancer testing (BRCA), tumor profiling, and prenatal screening. Directly comparable as both operate CLIA-certified labs serving dermatologists and oncologists with proprietary genomic tests; Castle even acquired Myriad's MyPath Melanoma business.
- Veracyte: Molecular diagnostics company specializing in genomic tests for thyroid, prostate, breast, and lung cancers using RNA sequencing and machine learning. Directly comparable in business model (specialty lab-developed tests sold to clinicians via field sales) and clinical use case (urologic/oncology risk stratification).
- Natera: Molecular diagnostics company offering cell-free DNA tests including Signatera (tumor-informed MRD) and Empower (hereditary cancer). Comparable as a specialty oncology-focused diagnostics company with proprietary tests ordered by clinicians and reimbursed by payers.
- Lucid Diagnostics: Commercial-stage cancer diagnostics company focused on esophageal precancer detection with the EsoGuard test for Barrett's esophagus screening. Directly competes with Castle's TissueCypher test in the same GI/esophageal cancer risk stratification clinical workflow.
- Interpace Biosciences: Molecular diagnostics company offering tests for thyroid (ThyGeNEXT/ThyraMIR) and pancreatic cancer (PanDNA). Comparable as a smaller specialty diagnostics player offering proprietary molecular tests ordered by clinicians with similar field sales model and reimbursement dynamics.
Broad incumbents
- Exact Sciences: Larger molecular diagnostics company best known for Cologuard (colorectal cancer screening) and Oncotype DX (oncology). Comparable as a publicly traded diagnostics company operating specialty labs and commercializing proprietary cancer tests to clinicians, but operates at much greater scale.
- NeoGenomics: Oncology-focused clinical laboratory services company offering comprehensive cancer testing across solid tumors and hematologic malignancies. Comparable as a publicly traded cancer diagnostics lab, though it operates at much broader scale with both clinical trial and routine testing services.
- Guardant Health: Leading precision oncology liquid biopsy company offering Guardant360 and Reveal tests for tumor profiling and MRD monitoring. Comparable as a publicly traded molecular oncology diagnostics company operating CLIA-certified labs and reimbursed by payers.
Emerging players
- Adaptive Biotechnologies: Molecular diagnostics company leveraging immune receptor sequencing for clonoSEQ (MRD) and T-Detect (immune-based disease detection). Comparable as an oncology-focused molecular diagnostics business with proprietary GEP-style technology sold to clinicians, though at smaller scale.
- HTG Molecular Diagnostics: Molecular diagnostics company offering HTG EdgeSeq technology for gene expression profiling. Comparable as a smaller specialty molecular diagnostics player with proprietary gene expression-based profiling technology targeting oncology indications.
Market position
Strengths5 records
Weaknesses3 records
Competitive moat6 records
Key risks6 records
Key highlights7 records
Customer concentration
Castle Biosciences social profiles
Digital presenceCastle Biosciences compliance and trust
Trust signalCompliance4 records
Castle Biosciences financial estimates
Financial estimateRevenue estimate
Valuation estimate
Castle Biosciences leadership team
Management profileNumber of profiles
Profiles6 records
Castle Biosciences subsidiaries and ownership
Company hierarchySubsidiaries4 records
Castle Biosciences funding detail
Funding detailFunding overview
Funding rounds16 records
Investors11 records
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Castle Biosciences M&A and investment
M&A and investmentM&A4 records
Investments1 record
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Castle Biosciences
What does Castle Biosciences do?
Castle Biosciences develops and commercializes proprietary molecular diagnostic and prognostic tests that use gene expression profiling and AI-driven spatialomics to inform cancer and dermatologic disease management decisions. Tests are ordered by healthcare providers and processed in the company's CLIA-certified, CAP-accredited laboratory, with results delivered through a secure clinician portal. Core offerings include DecisionDx-Melanoma, DecisionDx-SCC, DecisionDx-UM, TissueCypher, MyPath Melanoma, AdvanceAD-Tx, and adjunct DecisionDx-PRAME and DecisionDx-UM*Seq* tests.
Is Castle Biosciences a public or private company?
Castle Biosciences is a public company. It is classified as public and is currently operating.
When was Castle Biosciences founded?
Castle Biosciences was founded in 2008. It employs 501 to 1,000 people.
Where is Castle Biosciences based?
Castle Biosciences is headquartered in Friendswood, United States, in the North America region.
How does Castle Biosciences make money?
One revenue line is on record: laboratory Diagnostic Testing Services.
Who are Castle Biosciences's main competitors?
Direct peers on record are Myriad Genetics, Veracyte, Natera, Lucid Diagnostics and Interpace Biosciences. Broad incumbents are Exact Sciences, NeoGenomics and Guardant Health. Emerging players are Adaptive Biotechnologies and HTG Molecular Diagnostics.
Does Castle Biosciences have an API?
No public API is recorded for Castle Biosciences.
What industry is Castle Biosciences in?
Castle Biosciences's product category is Molecular Diagnostics. Its primary akta.pro industry code is HLAGADAF, Molecular & Genetic Testing (PCR/NGS/qPCR), with a secondary code of HLAAALAE, Oncology Diagnostics (tumor profiling, MRD, liquid biopsy). Its NAICS code is 621511 and its SIC code is 8071.