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Side-by-side financial comparison of CASTLE BIOSCIENCES INC (CSTL) and Montauk Renewables, Inc. (MNTK). Click either name above to swap in a different company.
CASTLE BIOSCIENCES INC is the larger business by last-quarter revenue ($83.7M vs $43.4M, roughly 1.9× Montauk Renewables, Inc.). Montauk Renewables, Inc. runs the higher net margin — 5.7% vs -17.4%, a 23.1% gap on every dollar of revenue. On growth, Montauk Renewables, Inc. posted the faster year-over-year revenue change (56.7% vs -4.9%). Over the past eight quarters, Montauk Renewables, Inc.'s revenue compounded faster (5.8% CAGR vs -1.9%).
Castle Biosciences Inc. is a commercial-stage diagnostic firm that develops and markets proprietary, clinically actionable tests for dermatological conditions such as melanoma and other skin cancers, plus rare diseases. It operates mainly in the U.S. healthcare market, focusing on segments with high unmet need for more accurate diagnostics to guide treatment choices.
Montauk Renewables, Inc. is a US-based renewable energy firm specializing in capturing and converting biogenic methane from landfills and agricultural waste into renewable natural gas (RNG) and low-carbon electricity. It serves utility, commercial, and industrial customers across North America, with operations focused on advancing decarbonization and sustainable energy transition goals.
CSTL vs MNTK — Head-to-Head
Income Statement — Q1 FY2026 vs Q4 FY2025
| Metric | | |
|---|---|---|
| Revenue | $83.7M | $43.4M |
| Net Profit | $-14.5M | $2.5M |
| Gross Margin | — | — |
| Operating Margin | — | -3.8% |
| Net Margin | -17.4% | 5.7% |
| Revenue YoY | -4.9% | 56.7% |
| Net Profit YoY | 43.8% | 129.5% |
| EPS (diluted) | $-0.49 | $0.01 |
Green = leading value per metric. Periods may differ when fiscal calendars don't align.
8-Quarter Revenue & Profit Trend
Side-by-side quarterly history. Quarters aligned by calendar period so offset fiscal years line up.
| Q1 26 | $83.7M | — | ||
| Q4 25 | $87.0M | $43.4M | ||
| Q3 25 | $83.0M | $45.3M | ||
| Q2 25 | $86.2M | $45.1M | ||
| Q1 25 | $88.0M | $42.6M | ||
| Q4 24 | $86.3M | $27.7M | ||
| Q3 24 | $85.8M | $65.9M | ||
| Q2 24 | $87.0M | $43.3M |
| Q1 26 | $-14.5M | — | ||
| Q4 25 | — | $2.5M | ||
| Q3 25 | $-501.0K | $5.2M | ||
| Q2 25 | $4.5M | $-5.5M | ||
| Q1 25 | $-25.8M | $-464.0K | ||
| Q4 24 | — | $-8.5M | ||
| Q3 24 | $2.3M | $17.0M | ||
| Q2 24 | $8.9M | $-712.0K |
| Q1 26 | — | — | ||
| Q4 25 | 79.0% | — | ||
| Q3 25 | 77.5% | — | ||
| Q2 25 | 79.5% | — | ||
| Q1 25 | 81.4% | — | ||
| Q4 24 | 81.3% | — | ||
| Q3 24 | 81.8% | 43.8% | ||
| Q2 24 | 83.3% | 15.6% |
| Q1 26 | — | — | ||
| Q4 25 | -4.4% | -3.8% | ||
| Q3 25 | -8.2% | 9.8% | ||
| Q2 25 | -4.9% | -5.2% | ||
| Q1 25 | -31.7% | 1.0% | ||
| Q4 24 | 4.7% | -35.5% | ||
| Q3 24 | 5.9% | 34.4% | ||
| Q2 24 | 5.8% | 2.0% |
| Q1 26 | -17.4% | — | ||
| Q4 25 | — | 5.7% | ||
| Q3 25 | -0.6% | 11.5% | ||
| Q2 25 | 5.2% | -12.2% | ||
| Q1 25 | -29.4% | -1.1% | ||
| Q4 24 | — | -30.5% | ||
| Q3 24 | 2.6% | 25.9% | ||
| Q2 24 | 10.3% | -1.6% |
| Q1 26 | $-0.49 | — | ||
| Q4 25 | $-0.06 | $0.01 | ||
| Q3 25 | $-0.02 | $0.04 | ||
| Q2 25 | $0.15 | $-0.04 | ||
| Q1 25 | $-0.90 | $0.00 | ||
| Q4 24 | $0.32 | $-0.05 | ||
| Q3 24 | $0.08 | $0.12 | ||
| Q2 24 | $0.31 | $-0.01 |
Balance Sheet & Financial Strength
Snapshot of each company's liquidity, leverage and book value from the latest quarter.
| Metric | | |
|---|---|---|
| Cash + ST InvestmentsLiquidity on hand | $63.8M | $23.8M |
| Total DebtLower is stronger | $10.1M | $126.0M |
| Stockholders' EquityBook value | $461.4M | $263.1M |
| Total Assets | $547.8M | $435.5M |
| Debt / EquityLower = less leverage | 0.02× | 0.48× |
8-quarter trend — quarters aligned by calendar period.
| Q1 26 | $63.8M | — | ||
| Q4 25 | $299.5M | $23.8M | ||
| Q3 25 | $287.5M | $6.8M | ||
| Q2 25 | $275.9M | $29.1M | ||
| Q1 25 | $275.2M | $40.1M | ||
| Q4 24 | $293.1M | $45.6M | ||
| Q3 24 | $95.0M | $55.0M | ||
| Q2 24 | $85.6M | $42.3M |
| Q1 26 | $10.1M | — | ||
| Q4 25 | $10.1M | $126.0M | ||
| Q3 25 | $10.0M | $54.9M | ||
| Q2 25 | $10.0M | $57.8M | ||
| Q1 25 | $10.0M | $40.8M | ||
| Q4 24 | $10.0M | $43.8M | ||
| Q3 24 | $10.0M | $46.7M | ||
| Q2 24 | $10.0M | $49.7M |
| Q1 26 | $461.4M | — | ||
| Q4 25 | $470.9M | $263.1M | ||
| Q3 25 | $467.0M | $260.7M | ||
| Q2 25 | $455.4M | $254.7M | ||
| Q1 25 | $440.3M | $258.2M | ||
| Q4 24 | $455.8M | $257.4M | ||
| Q3 24 | $441.1M | $275.3M | ||
| Q2 24 | $423.9M | $255.3M |
| Q1 26 | $547.8M | — | ||
| Q4 25 | $578.6M | $435.5M | ||
| Q3 25 | $562.8M | $383.3M | ||
| Q2 25 | $544.7M | $382.5M | ||
| Q1 25 | $501.7M | $354.2M | ||
| Q4 24 | $531.2M | $349.0M | ||
| Q3 24 | $514.6M | $374.1M | ||
| Q2 24 | $487.3M | $362.0M |
| Q1 26 | 0.02× | — | ||
| Q4 25 | 0.02× | 0.48× | ||
| Q3 25 | 0.02× | 0.21× | ||
| Q2 25 | 0.02× | 0.23× | ||
| Q1 25 | 0.02× | 0.16× | ||
| Q4 24 | 0.02× | 0.17× | ||
| Q3 24 | 0.02× | 0.17× | ||
| Q2 24 | 0.02× | 0.19× |
Cash Flow & Capital Efficiency
How much cash each business actually produces after reinvestment. Cash flow is harder to manipulate than net income.
| Metric | | |
|---|---|---|
| Operating Cash FlowLast quarter | $-22.1M | $337.0K |
| Free Cash FlowOCF − Capex | — | $-41.1M |
| FCF MarginFCF / Revenue | — | -94.7% |
| Capex IntensityCapex / Revenue | — | 95.5% |
| Cash ConversionOCF / Net Profit | — | 0.14× |
| TTM Free Cash FlowTrailing 4 quarters | — | $-86.2M |
8-quarter trend — quarters aligned by calendar period.
| Q1 26 | $-22.1M | — | ||
| Q4 25 | $26.9M | $337.0K | ||
| Q3 25 | $22.6M | $12.7M | ||
| Q2 25 | $20.8M | $8.2M | ||
| Q1 25 | $-6.0M | $9.1M | ||
| Q4 24 | $24.4M | $724.0K | ||
| Q3 24 | $23.3M | $28.6M | ||
| Q2 24 | $24.0M | $193.0K |
| Q1 26 | — | — | ||
| Q4 25 | $19.7M | $-41.1M | ||
| Q3 25 | $7.8M | $-17.2M | ||
| Q2 25 | $11.6M | $-25.5M | ||
| Q1 25 | $-10.8M | $-2.5M | ||
| Q4 24 | $16.8M | $-8.3M | ||
| Q3 24 | $17.0M | $16.0M | ||
| Q2 24 | $18.8M | $-18.6M |
| Q1 26 | — | — | ||
| Q4 25 | 22.7% | -94.7% | ||
| Q3 25 | 9.4% | -37.9% | ||
| Q2 25 | 13.4% | -56.4% | ||
| Q1 25 | -12.2% | -5.8% | ||
| Q4 24 | 19.5% | -29.8% | ||
| Q3 24 | 19.8% | 24.3% | ||
| Q2 24 | 21.6% | -42.9% |
| Q1 26 | — | — | ||
| Q4 25 | 8.3% | 95.5% | ||
| Q3 25 | 17.9% | 65.9% | ||
| Q2 25 | 10.7% | 74.6% | ||
| Q1 25 | 5.4% | 27.3% | ||
| Q4 24 | 8.8% | 32.5% | ||
| Q3 24 | 7.4% | 19.1% | ||
| Q2 24 | 6.0% | 43.3% |
| Q1 26 | — | — | ||
| Q4 25 | — | 0.14× | ||
| Q3 25 | — | 2.43× | ||
| Q2 25 | 4.60× | — | ||
| Q1 25 | — | — | ||
| Q4 24 | — | — | ||
| Q3 24 | 10.29× | 1.68× | ||
| Q2 24 | 2.69× | — |
Financial Flow Comparison
Revenue → gross profit → operating profit → net profit for each company.
Revenue Breakdown by Segment
CSTL
Segment breakdown not available.
MNTK
| Natural Gas Environmental Attributes | $28.1M | 65% |
| Natural Gas Commodity | $10.7M | 25% |
| Electric Commodity | $2.7M | 6% |
| Electric Environmental Attributes | $2.0M | 5% |
