The business screen
Core haram lines: conventional banking and insurance, alcohol, pork, gambling, adult entertainment, and (on most screens) weapons. Cannabis is treated as haram by the major index providers. Media and hotels are judgement calls when a slice of revenue is from a bar or casino.
AAOIFI and the Dow Jones Islamic Market indexes allow a small tolerance — commonly 5% of revenue — for incidental haram income, then require purification of your dividend. Tolerance is not a business plan. A pub chain is not “5% alcohol”.
The financial screen
Even a halal trade can be built on riba. Typical AAOIFI-style caps: interest-bearing debt over market cap (or total assets) below 30%; cash plus interest-bearing securities below 30%; receivables below 67% of assets on some methodologies. DJIM uses trailing-24-month market cap and slightly different ratios. The screening desk lets you run both.
Market-cap screens move with the share price. A company can fall in and out. That is why a quarterly review beats a one-off tweet from a screener app.
Funds, sukuk, gold, property
An “Islamic” ETF is only as good as its index and its purification policy. Read the KIID. Sukuk are closer to asset-based certificates than to conventional bonds — still read whether you own a share of an asset or merely a debt in Arabic.
Physical gold and silver, bought spot and held, are widely accepted. Leveraged gold “accounts” and unallocated pool products often reintroduce gharar or riba. Direct residential property you rent out is trade plus ijara. A REIT still needs a screen.