Is Masimo Stock (MASI) Halal? A Complete Analysis

The Short Answer

Masimo stock (MASI) is generally considered halal by most Islamic scholars and Sharia screening criteria, with leverage as the primary consideration. Masimo is a medical-technology company specializing in noninvasive patient monitoring.

Development and sale of medical-monitoring devices is a permissible healthcare activity at the activity level. The main consideration is the financial screen: Masimo took on acquisition-related debt for its consumer-audio segment, so the debt-to-market-cap ratio should be verified against the 33% threshold at the time of investment.

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)

Masimo's Business Activity

Masimo's products include:

• Pulse oximetry: Signature SET measure-through-motion sensors and monitors
• Advanced monitoring: Brain-function, hemoglobin, and other noninvasive parameters
• Connected care: Hospital-automation and patient-safety platforms

This is a permissible healthcare and medical-device business at the activity level. Masimo also operates a smaller consumer-audio and health segment.

Concerns to Be Aware Of

1. Leverage — The Primary Screen

Masimo took on acquisition-related debt in connection with its consumer-audio (Sound United) acquisition. The debt-to-market-cap ratio should be verified against the 33% Sharia threshold at the time of investment, though the company generates strong operating cash flow and has been reducing leverage. This is the primary Sharia-screening consideration.

2. Segment Restructuring

Masimo has been evaluating strategic alternatives for its non-healthcare consumer-audio segment. Corporate restructuring can affect leverage and the asset mix, so the financial screen should be re-verified following material transactions.

3. Interest Income

Interest income from cash balances should be checked against the 5% interest-income-to-revenue threshold and the relevant portion purified.

Financial Ratios (2025)

Based on Masimo's most recent financial statements:

• Total Debt / Market Cap: Acquisition-related leverage — verify against the 33% threshold at the time of investment ⚠️
• Interest Income / Revenue: Under 5% — verify ✅
• Haram Revenue: Negligible (medical devices) ✅
• Business Activity: Permissible healthcare / medical technology ✅

Verdict from Major Screening Agencies

Masimo stock is generally screened as compliant (halal) with purification, subject to leverage verification by:

• Zoya App — Generally compliant, verify financials ✅
• MSCI Islamic criteria — Generally included subject to ratios ✅
• Most major Sharia advisory boards — Compliant with purification, subject to debt-ratio verification ✅

Bottom Line

Masimo (MASI) is generally halal with purification for Muslim investors, subject to verifying the debt ratio at the time of investment. The core business — noninvasive patient-monitoring technology — is a permissible healthcare activity. Because Masimo carries acquisition-related leverage, the most important step is confirming the debt-to-market-cap ratio sits below the 33% threshold, then purifying a small portion of any interest income.

For Muslim investors seeking medical-device exposure, MASI sits alongside other halal-screened names like Inspire Medical (INSP) and Boston Scientific (BSX).