The Short Answer
Tandem Diabetes stock (TNDM) is generally considered halal for Muslim investors, subject to the balance-sheet ratios. Tandem Diabetes Care designs and sells insulin-delivery systems — including its t:slim X2 and Mobi automated insulin pumps and related software — that help people with diabetes manage their condition. Selling medical devices that treat a chronic illness is a permissible activity, so the business-activity screen passes.
The verdict depends on the balance sheet: Tandem has historically funded growth with convertible senior notes, so confirm the total-debt-to-market-cap ratio against the 33% threshold using the latest filings, and purify the interest income on cash.
Sharia Screening Methodology
Islamic scholars use several criteria to screen stocks:
- Business activity screen: Is the company's primary business halal?
- Debt ratio: Total debt / market cap must be under 33%
- Interest income: Interest income / total revenue must be under 5%
- Haram revenue: Revenue from haram sources must be under 5%
- Receivables ratio: Total receivables / total assets must be under 49–70% (varies by board)
What Tandem Diabetes Does
Tandem Diabetes Care, Inc. (headquartered in San Diego, California) makes diabetes-management technology:
- Insulin pumps: The t:slim X2 and Mobi automated insulin-delivery systems.
- Software and algorithms: Automated insulin-dosing technology integrated with continuous glucose monitors.
- Supplies: Recurring cartridges and infusion sets.
Selling medical devices that treat a chronic illness is a permissible activity, so the business-activity screen passes.
Why It Passes (and What to Check)
1. Permissible Core Business
Tandem's revenue comes from insulin-delivery devices and supplies that help people manage diabetes — a clearly permissible activity that benefits human health. There is no haram revenue line.
2. Debt Ratio (Deciding Screen)
Tandem has historically funded growth with convertible senior notes, so confirm the total-debt-to-market-cap ratio against the 33% threshold using the latest filings. This is the deciding screen for the verdict.
3. Interest Income (Purify)
Tandem earns interest income on its cash and investment balances. This should be checked against the 5% threshold and the corresponding portion of returns purified.
Financial Ratios
Based on Tandem's most recent financial statements:
- Total Debt / Market Cap: Convertible notes — confirm against filings ⚠️ (threshold: under 33%)
- Interest Income: On cash/investments — check and purify ⚠️ (threshold: under 5%)
- Haram Revenue: None ✅ (threshold: under 5%)
- Receivables Ratio: Confirm against filings ⚠️ (threshold: 49–70%, varies by board)
Assuming the ratios hold, TNDM screens as halal — it is a competitive, still-scaling device business, so re-screen periodically.
What About Purification?
Purify the portion of returns attributable to interest income earned on Tandem's cash and investment balances — donating that share of gains to charity.
Verdict from Major Screening Agencies
Tandem Diabetes stock is generally screened as halal by:
- Zoya App — Compliant subject to ratios ✅
- MSCI Islamic criteria — Compliant subject to debt ratio ✅
- Most major Sharia advisory boards — Halal with routine purification ✅
Bottom Line
Tandem Diabetes (TNDM) is generally halal for Muslim investors, subject to the balance-sheet ratios. The insulin-pump business is clearly permissible. Confirm the debt and receivables ratios against the latest filings — the convertible notes make the debt screen the deciding one — purify the interest income, and re-screen periodically.
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