Is CSTL halal?
Castle Biosciences, Inc.
Not halal
Castle Biosciences, Inc. did not pass AAOIFI screening. The failed check is shown below.
Checked: 13 October 2026
Exchange
NASDAQ
Price
31.96
Day
-5.44%
Market cap
$1.00B
Industry
Diagnostics & Research
Sector
Healthcare
What the company does
Castle Biosciences sells gene-expression tests (DecisionDx) that gauge how dangerous a skin cancer (melanoma, squamous cell) or other condition is. Money comes from insurers and Medicare paying for tests doctors order.
What was checked
The AAOIFI standard has four steps: business activity first, then three financial ratios. Fail one and the stock is not halal.
Business activity
No prohibited activity
Interest-bearing debt / market cap
limit 30%
Interest-bearing debt $10.34M ÷ 36-month average market cap $707.28M = 1.5%
1.5%
Pass
Cash & investments / market cap
limit 30%
Cash + interest-bearing securities $266.81M ÷ 36-month average market cap $707.28M = 37.7%
37.7%
Fail
Non-compliant income / total revenue
limit 5%
Interest income $11.77M ÷ annual revenue $344.23M (2025) = 3.4%
3.4%
Pass
Figures from the company's filings (2026-06-30), USD. Market cap is a 36-month average (the S&P Shariah index approach), so a one-day price move does not flip the verdict. Today's market cap: $1.00B.
For information (AAOIFI 3/1 note): cash + receivables are 56.2% of total assets (2026-06-30). AAOIFI recommends tangible assets of at least one third — this figure does not affect the verdict, and other major screeners do not apply it either.
In the lists
- In the S&P 500
- Not in the S&P 500
- Held by funds
- Not held by any tracked fund
Halal stocks in the same industry
The largest halal stocks in Diagnostics & Research — for comparison.
Related articles
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- Halal investingBlogWhy a company's cash affects whether its stock is halalLots of cash sounds like a good sign — but halal screening checks it separately. What counts, what doesn't, and where we are stricter than AAOIFI.
- Halal investingBlogAAOIFI Shariah Standard No. 21 in plain languageThe most widely used standard for halal stock screening: the two-step test, the three ratios and how it differs from other methods.
Halal is the first question. The second: when to enter?
Our scanner watches 1454 halal stocks around the clock and fires a signal with entry, TP and SL when a technical setup completes. The full signal history — with outcomes — is public.
This is neither investment advice nor a fatwa. Screening is based on public financial statements and AAOIFI standard No. 21; data may lag. For a personal decision consult your own scholar.