Castle Biosciences — Third Quarter 2026 Earnings Summary

Financial Performance:

• Q3 2026 revenue was $102.9 million, a 24% increase compared to $83.0 million in Q3 2025.
• Nine months ended September 30, 2026, revenue was $290.1 million, compared to $257.2 million for the same period in 2025.
• Q3 2026 gross margin was 75% and adjusted gross margin was 77%, unchanged from Q3 2025.
• Nine months 2026 gross margin was 74% (up from 67% in 2025) and adjusted gross margin was 77% (down from 80% in 2025).
• Q3 2026 net loss was $4.1 million, compared to a net loss of $0.5 million in Q3 2025.
• Nine months 2026 net loss was $20.7 million, compared to a net loss of $21.8 million in the same period in 2025.
• Q3 2026 adjusted EBITDA was $12.7 million, compared to $9.2 million in Q3 2025.
• Nine months 2026 adjusted EBITDA was $20.0 million, compared to $32.5 million in the same period in 2025.
• Q3 2026 net cash provided by operating activities was $19.7 million, compared to $22.6 million in Q3 2025.
• Nine months 2026 net cash provided by operating activities was $12.8 million, compared to $37.4 million in the same period in 2025.
• As of September 30, 2026, cash, cash equivalents, and marketable investment securities totaled $277.7 million.
• Total debt as of September 30, 2026, was $10.1 million ($4.2 million current portion and $5.9 million long-term).

Guidance and Future Outlook:

• Full-year 2026 revenue guidance raised to $385-395 million from the previous range of $365-375 million.
• Company maintains expectations to achieve positive adjusted EBITDA for Q4 2026, the full year 2026, and the full year 2027.

Business Segments and Product Lines:

• TissueCypher test report volume increased 47% in Q3 2026 compared to Q3 2025.
• DecisionDx-Melanoma test report volume grew 5% year-over-year in the first nine months of 2026.
• Dermatology commercial team delivered 15,168 test reports in Q3 2026.
• Core revenue drivers (DecisionDx-Melanoma and TissueCypher) saw a 22% increase in test reports in Q3 2026 and a 29% increase in the nine months ended September 30, 2026.
• New tests launched in the reporting period include AdvanceAD-Tx (1,109 reports in Q3, 2,548 in nine months) and Esopredict (469 reports in Q3, 986 in nine months), neither of which were offered in the prior year periods.
• DecisionDx-SCC test reports declined 7% in Q3 2026 (3,882 vs 4,186) and 13% in the nine months 2026 (11,595 vs 13,323), attributed to changes in Medicare coverage effective April 24, 2025.
• MyPath Melanoma test reports decreased 31% in Q3 2026 (798 vs 1,151) and 13% in the nine months 2026 (2,832 vs 3,243).
• DecisionDx-UM test reports were 422 in Q3 2026 (down 3% from 436) and 1,396 in the nine months 2026 (up 2% from 1,374).

Market and Competitive Landscape:

• New clinical data presented at the EADV Congress 2026 supports DecisionDx-Melanoma use in sentinel lymph node biopsy decision-making and risk of recurrence management.
• Publication in the Journal of the American Academy of Dermatology (JAAD) validated the integrated DecisionDx-SCC test result for high-risk cutaneous squamous cell carcinoma patients.
• New study highlights patient interest in molecular testing for atopic dermatitis, supporting the clinical need for AdvanceAD-Tx.
• Published studies demonstrate TissueCypher Barrett's Esophagus test guides risk-aligned management decisions and aligns management with individual progression risk.
• Collaboration with SciBase includes an additional order of approximately $0.6 million for portable pen devices and electrodes to accelerate clinical studies.

Risks and Challenges:

• Revenue comparisons for the nine months 2026 were affected by the discontinuation of the IDgenetix test in May 2025 and the re-focus of commercial efforts.
• Net loss per share for the nine months 2026 was $0.69, compared to $0.76 in 2025, driven by stock-based compensation expense of $32.6 million.
• Forward-looking statements note risks including reimbursement assumptions, macroeconomic conditions, clinical study delays, and potential failure of new tests to meet financial targets.

Management Commentary and Tone:

• CEO Derek Maetzold described the quarter as "strong," citing consistent execution across the portfolio.
• Management highlighted TissueCypher as a key contributor to top-line performance with 47% year-over-year growth in test report volume.
• Management noted disciplined expense management and operational efficiency while continuing to invest in strategic growth.
• The tone emphasized the strength of the portfolio and progress toward long-term growth objectives.

Other Key Points:

• Opened a new 55,000-square-foot laboratory and office facility in Scottsdale, Arizona, within the Perimeter Center business park.
• Stock-based compensation expense was $11.2 million for Q3 2026 and $32.6 million for the nine months 2026.
• Amortization of acquired intangible assets was $2.1 million for Q3 2026 and $6.6 million for the nine months 2026.
• The IDgenetix test was discontinued in May 2025, impacting prior year comparisons.
• Conference call and webcast held on November 5, 2026, at 4:30 p.m. ET.