Forensic Analysis · Healthcare / Pharmaceuticals / Biotech · as of Sep 25, 2026
Castle Biosciences Inc (CSTL)
A forensic read on Castle Biosciences Inc built from its complete SEC filings — financial-health screens, earnings quality, red flags and a price-aware rating. Reproducible math, not opinion.
D · Weak — demands caution
Forensic grade
Safe
Financial health
11.9
Distress distance
Clean
Earnings quality
3
Forensic signals
-53.6
P / E (ttm)
-5.1%
ROE
$1.1B
Market cap
0.00%
Dividend yield
3.7%
Revenue growth
This free snapshot doesn't read filing or proxy text, so the auditor-quality and governance checks that can lower a grade were not evaluated (red flags, auditor quality, say on pay, board independence, going concern, valuation). Those checks only ever lower a grade, so the full analysis can land below the grade above but never above it — treat it as the most favourable reading, not the settled one.
Castle Biosciences Inc earns a D (Weak — demands caution) forensic quality grade, and its balance-sheet distress test reads 11.9, placing it in the Safe zone. 3 forensic signals were flagged in its latest SEC filings, led by return on invested capital.
What the filings flag
-8.6%
FY2025
Return on invested capital.Return on invested capital is -8.6% in the latest fiscal year, against -17.5% in FY2023, having run between -17.5% and 1.9% across FY2023–FY2025 with no direction held. After-tax operating profit was ($54M) in FY2023 and ($34M) in FY2025, with operating income at -30.9% of revenue in FY2023, 2.6% in FY2024 and -12.4% in FY2025. The capital base behind it grew +28% across FY2023–FY2025, from $307M to $394M, and the return did not fall doing it, so the dollars added over that window earned at least the -17.5% the older base was already earning.
+4.0%/yr
FY2023–FY2025
Share-count dilution.Diluted share count changed +8% over the last 2 years to FY2025 (+4.0%/yr). The count is growing: more stock was issued than repurchased over this window, so aggregate results grew faster than their per-share equivalents. That's ~4.0% shaved off per-share growth every year — total profit has to grow that much just to keep earnings-per-share flat, and a stake held since FY2023 has been diluted ~8%.
13% of rev
FY2025
Stock-based comp load.Stock-based compensation ran 13% of revenue and 162% of free cash flow in FY2025 — about $1.58 per diluted share. No cash left the business to pay it, which is why operating cash flow adds it back. Net of repurchases the diluted count still rose about 4.1% a year, and the rate is falling. Stock compensation is one source of that issuance; acquisition consideration, equity raises, convertibles and other employee plans also net into the count, and these figures do not separate them.
Key fundamentals
Latest Revenue$344.2M
Revenue Growth YoY+3.7%
Revenue CAGR (2yr)+25.1%
Net Margin-7.0%
Free Cash Flow$28.3M
Return on Equity-5.1%
Debt / Equity0.02x
The forensic grade and screens above are free — no account needed. Want the AI investment read on top — the 0–100 rating, thesis, bull-vs-bear, red flags and the 12-month scenario, written from Castle Biosciences Inc's actual 10-K/10-Q/8-K filings?