Shariah Screening Ratios, Purification and Ongoing Portfolio Monitoring
Direct answer
Shariah investment screening normally combines a business-activity test with financial-ratio tests under a named methodology. Purification addresses a limited investor-attributable amount of incidental non-permissible income where that method allows it; it does not make a prohibited business permissible. Because accounts, market values and company activities change, investors need documented calculations, trigger-based reviews and a clear policy for status changes.
Key takeaways
Screening begins with the company’s primary business, then moves to financial tests.
Ratios and thresholds differ across recognised methodologies; consistency is essential.
Data periods, denominators and classification choices can change the result.
Purification is limited and method-specific, not a general cure.
Compliance status can change after results, acquisitions or market-value movements.
Screening, investment merit and personal suitability are separate decisions.
Why financial screens exist
A company may sell permissible products yet use interest-bearing debt, hold interest-generating assets or receive a small amount of non-permissible income. Contemporary Shariah screening methodologies address these mixed features through defined limits and processes.
This creates a disciplined boundary, but it also creates a responsibility: the analyst must use the current standard accurately. A ratio seen in a social post is not enough. The methodology determines what enters the numerator, what denominator is used, the relevant period and what happens near or beyond the limit.
The two-stage framework
Stage 1: business-activity screen
Identify the company’s products, services, segments and material subsidiaries. Widely used approaches exclude businesses centred on conventional interest-based finance, gambling, alcohol, pork-related products and other prohibited activities specified by the standard.
Review annual-report segment notes and recent market announcements. A diversified group can require more analysis than its sector label suggests. When revenue classification is unclear, record the uncertainty and seek evidence rather than assuming a pass.
Stage 2: financial screens
If the core business passes, apply each financial screen in the chosen methodology. These may address interest-bearing debt, cash or interest-related instruments, receivables and incidental non-permissible income. Names and formulas vary.
Do not publish a universal threshold table without tying it to a specific current source. Even when two standards show a similar percentage, one may use total assets while another uses market capitalisation or a moving average. Those are not interchangeable calculations.
For company-level implementation, use our practical JSE share-screening checklist.
How denominator choice affects the result
Assume a hypothetical company has R250 million of a screened balance-sheet item. Under a method using R1 billion of total assets, the ratio would be 25%. Under a method using a changing market-value denominator, the ratio could be higher or lower even though the company’s accounts did not change.
This is why analysts must record the methodology, period and market-data date. It also explains why a share can change status after a large price movement under a market-value-based approach.
The example illustrates mechanics only. It does not apply or endorse a threshold and does not establish the status of a real company.
A reproducible calculation record
For every security, keep:
Record | Minimum detail |
|---|---|
Security identity | Legal name, exchange, ticker and identifier |
Methodology | Issuer, version, publication date and access date |
Business review | Segments, prohibited exposure, source pages and conclusion |
Financial period | Reporting end date and whether statements are audited/interim |
Ratio inputs | Exact value, units, classification and primary source |
Market inputs | Date, price/value source and averaging method if required |
Calculation | Formula, unrounded result and threshold from the method |
Purification | Factor, distribution basis, amount and disposal record |
Review | Analyst, reviewer, date, decision and next trigger |
This evidence supports governance, correction and consistent treatment across a portfolio.
Common screening errors
Mixing methodologies
Selecting the most convenient rule from several standards is not a valid hybrid. Adopt a method, document it and escalate genuine interpretation issues.
Using stale inputs
Company results and market values change. A spreadsheet copied forward without refreshed inputs can produce a false conclusion.
Comparing figures from different periods
Annual debt, interim cash and today’s market value may not be permitted together under the selected method. Follow the prescribed timing rules.
Ignoring corporate structure
Subsidiaries, associates, joint ventures, treasury activities and recent acquisitions can affect business and financial screens. Consolidated numbers do not always answer every segment question.
Rounding away a breach
Keep full precision for the decision. A borderline result should prompt review, not creative rounding.
Treating data vendors as the final authority
Screeners and portals are useful, but their classifications, periods and formulas can differ. Trace material inputs to company documents and the named methodology.
What purification means
Where an otherwise eligible company earns a limited amount of incidental non-permissible income, the chosen methodology may require the attributable portion to be disposed of for charitable purposes without seeking spiritual reward from the impermissible amount itself. The objective is not to transform prohibited income into permissible personal income.
Purification practice can differ. A provider may publish a per-share factor, a percentage of a distribution or another calculation. Use the factor for the relevant period and holding. Keep records of distributions, holding quantities, calculations and disposal.
What purification does not do
It does not permit investment in a company whose principal business is prohibited.
It does not cure an impermissible contract or trading method.
It does not justify ignoring financial-screen failures.
It does not replace Zakah; they are separate concepts and calculations.
It does not authorise an arbitrary donation percentage without a basis.
When a fund performs purification internally, confirm the scope before duplicating it. When it does not, obtain the relevant disclosed factor or qualified guidance.
Ongoing monitoring: a workable policy
Calendar-based review
Set reviews around annual and interim reporting cycles or official index-review dates. The appropriate frequency depends on the methodology and portfolio process.
Event-based review
Trigger a review after:
an acquisition, disposal or change in primary business;
a significant debt issue, refinancing or capital raise;
a major asset impairment or restructuring;
a new annual or interim report;
a large movement in the required market-value denominator; or
a status change published by the adopted screening provider.
Decision policy
Predefine what happens when a security moves from pass to review or fail. The policy should address verification, trade timing, purification and client communication where relevant. Different Shariah authorities may prescribe different treatment, particularly when non-compliance is temporary or discovered after the fact. Obtain qualified guidance for the adopted framework.
Screening pooled funds and ETFs
Investors in a unit trust or ETF usually rely on the fund’s disclosed mandate, index method and governance rather than calculating every constituent personally. Still verify:
the exact index or screening method;
the Shariah board or reviewer;
review and rebalance frequency;
treatment of non-compliant holdings;
whether purification occurs at fund level; and
where current holdings and reports are published.
Read our guides to Shariah-compliant ETFs for South Africans and unit-trust fees, tax and performance for product-level due diligence.
Screening is not portfolio construction
A list of passing shares can still be a poor portfolio. After screening, consider valuation, diversification, liquidity, governance, risk, time horizon and tax. Sector exclusions can create concentrated exposures, while several Islamic funds may hold the same large global companies.
The portfolio process should also consider emergency reserves, short-term liabilities, family protection and estate planning. A technically compliant security does not automatically suit every goal.
Governance questions for an adviser or manager
Which Shariah methodology do you use, and why?
Who approves interpretations and borderline cases?
How are data inputs sourced and checked?
Is screening performed before purchase and after each trigger?
How quickly are status changes investigated?
What is the disposal policy for a failed holding?
Who calculates purification, and how is it documented?
Can clients access the latest methodology and governance reports?
How are investment merit and suitability assessed after compliance?
Clear answers matter more than a generic “halal portfolio” label.
Frequently asked questions
Is there one universal Shariah screening ratio?
No. Recognised methodologies can differ in thresholds, denominators, periods and classifications. Use one current, documented method consistently.
Can purification make any share halal?
No. Purification generally addresses limited incidental non-permissible income in an otherwise eligible company under the adopted method. It does not cure a prohibited core business or failed screen.
Why can a share’s Shariah status change?
Business activities, debt, cash, receivables, income and market-value inputs can change. Methodologies and published data can also be updated.
Is purification the same as Zakah?
No. Purification disposes of identified non-permissible income under a Shariah process. Zakah is a separate obligation with its own rules and calculation.
Does passing a screen mean a share is a good investment?
No. Screening addresses compliance. Valuation, quality, diversification, risk and suitability require separate analysis.
Next step
Use the Shariah-compliant investing hub for the full process. If you prefer documented screening and ongoing portfolio oversight, explore MuslimFin managed portfolios.
Important: This article is general education, not a fatwa, tax opinion, security recommendation or personal financial advice. Screening standards, company information and outcomes change. Use current primary evidence and qualified Shariah and professional review.
