How to Purify Non-Compliant Crypto Income
ShariaQuant Research Board
Islamic Finance & Quantitative Cryptography
Almost every asset that passes a Shariah screen still carries a purification duty, and almost nobody pays it.
The reason is not negligence. It is that nobody sends you a statement. Your broker does not calculate it, your exchange does not mention it, and the halal lists that told you the asset was permissible stopped there. So the obligation sits unpaid, quietly, for years.
Here is the arithmetic, the actual rates, and the cases where purification is not available at all.
What purification is, and is not
Purification, tathir, is removing income that was never yours from an otherwise permissible holding.
Large operating companies earn a little interest on their cash reserves. That is unavoidable in a world of conventional banking, and prohibiting every business with a bank account would prohibit nearly all equity investment. The tradition's answer is a threshold plus a remedy: if the impure income is small, the holding is permissible, and you remove your share of the impure portion.
Two things it is not.
It is not zakat. Zakat is worship, owed on wealth, at 2.5% annually, whether your holdings are clean or not. Purification is restitution, owed on tainted income, at whatever rate the taint runs to. You may owe both, calculated separately. Zakat mechanics are here.
It is not charity you get credit for. Most scholars hold that you earn no reward for giving away money that was not lawfully yours. You are returning something, not donating it. Do not record it as sadaqah and do not feel generous about it.
The threshold that decides whether purification is even available
AAOIFI's screening standard, applied in our methodology, tolerates non-compliant income below 5% of total revenue, provided the holder purifies. At 5% or above, the asset fails the screen and purification is not a remedy.
This is the distinction people get wrong most often, so it is worth being blunt about it.
Purification handles incidental impurity in a sound business. Apple earns interest on its cash while selling phones. You clean the interest and keep the phones.
Purification cannot rescue an asset whose core business is the violation. Hyperliquid takes over 33% of revenue from perpetual futures and recycles roughly 99% of retained fees into token buybacks. There is no permissible business underneath to keep. Aave is a lending protocol; lending at interest is not a byproduct of Aave, it is Aave. Circle USYC exists to deliver Treasury interest to holders.
You cannot pay a percentage and keep a prohibited asset. Purification is not a toll.
The real rates
These are the published purification rates from our own screening, which give you a sense of the actual magnitude.
| Asset | Purification rate | Basis |
|---|---|---|
| Tesla xStock | ~1.5% | Ratio of Tesla's interest income to total revenue. Debt ratio ~1.3%, cash and securities ~3.56% |
| MicroStrategy xStock | 1.46% | Debt ratio 25.51%, cash and securities 6.87% |
| Broadcom xStock | ~0.54% | Passes all business and financial screens |
Notice how small these are. A 1.5% purification on a $10,000 position's dividend is not going to change your life, which is precisely why people skip it, and precisely why skipping it is hard to justify.
Note also that most native crypto assets carry no purification duty at all. Holding Bitcoin generates no impure income. Neither does holding USDT or USDC: their issuers earn enormous interest on reserves, but none of it reaches you, so there is nothing in your hands to clean.
What you actually purify
Purify the impure share of income received, not your capital gain.
This is the second big error. If your position rose from $10,000 to $15,000 because the price went up, that $5,000 is trading profit on a permissible asset. It is not tainted and it is not purified. Capital appreciation from market pricing has nothing to do with the company's interest income.
What you purify is the impure portion of distributions: dividends, revenue shares, and value delivered to you through corporate action.
The rebasing problem, which is specific to tokenized equities
Here is where it gets practically difficult, and where nearly everyone fails.
Tokenized equities from Backed Finance auto-reinvest dividends through a rebasing mechanism. The dividend never arrives as cash in your account. It arrives as an increase in the value of your tokens.
So there is nothing to purify from, in the sense of a payment you can take a percentage of. You have to reconstruct it:
- Find the dividends the underlying company declared during your holding period. Public information, on the company's investor relations page.
- Work out your share, based on how many tokens you held and when.
- Apply the purification rate to that reinvested dividend value, not to your total return.
- Donate it.
For Tesla, that is 1.5% of the dividend value attributable to your holding. For MicroStrategy, 1.46%. Nobody will prompt you and no interface will show you the number.
If that sounds like homework, it is. It is also about fifteen minutes a year and the alternative is holding money that is not yours.
The 100% cases
Sometimes the whole amount goes, not a percentage.
Interest you earned directly. If you deposited USDC into a lending protocol or an exchange Earn product and received yield, all of it must be donated. Not 1.5%. The entire amount, because the entire amount is riba rather than a tainted slice of a lawful return.
This applies even to assets that pass our screen. Ripple USD is Halal, and the moment you lend it out for yield, 100% of that yield is impure. The asset being clean says nothing about what you did with it.
Idle balance sweeps. Many bot frameworks and exchange accounts park uninvested capital in a yield venue by default. Check whether yours does, because this generates interest continuously without you deciding to, and it is the most common way a compliant strategy produces non-compliant income. More on bot settings here.
Proceeds attributable to a prohibited holding you are exiting. If you held something that fails the screen and are divesting, the mainstream view is that you may recover your capital and should purify the gain rather than keep it. Getting out is the priority; do not let uncertainty about the arithmetic delay the divestment.
Where it goes
Charity, given to the poor and needy. Most scholars hold it should not go to a mosque construction fund or to Qur'an printing, on the reasoning that impure money should not be directed to acts of worship or to your own community benefit. General welfare, food, medical relief and poverty alleviation are the standard destinations.
Do not claim it as your zakat. Different obligation, different money.
A practical routine
Do it annually, on the same date as your zakat, with separate records.
Once a year, list your holdings that carry a purification rate and note it. For each, find the declared dividends over the period and apply the rate. Separately, list any interest you received from any source and add 100% of it. Total, donate, record it.
Two ledgers, one date. Zakat on the left, purification on the right, and they never touch.
The honest caveat
Scholars differ on the details: whether purification applies to capital gains as well as dividends, how to treat a partial year, and whether a purified holding needs anything further. The position above, purify distributions and not appreciation, is the mainstream one and the one AAOIFI's framework implies.
Where I would not hedge is the direction of error. If you are unsure of the amount, give more rather than less. It was not yours.
