How to Write a Privacy Policy for a Crypto or Web3 Platform

A generic privacy policy template assumes personal data lives in one database you control, and that a deletion request is as simple as running a DELETE statement. Neither assumption holds for a crypto or Web3 platform. Wallet activity sits on a public ledger you don't operate and can't edit. Identity verification, if your platform does any, usually runs through a third-party provider you don't build yourself. And a single user interaction can produce two very different kinds of record: one you can delete on request, and one that will exist permanently whether you want it to or not. A privacy policy that doesn't draw these lines clearly ends up either overpromising control you don't have or underexplaining data handling that regulators and users both expect to see spelled out.

Wallet addresses are pseudonymous, not anonymous

The most common inaccuracy in crypto privacy policies is describing wallet addresses as anonymous. They aren't, and the distinction matters both legally and practically. A wallet address is a string of characters with no name attached at the protocol level, which is what makes it pseudonymous rather than directly identifying on its face. But every transaction that address has ever made is permanently visible on a public blockchain, and blockchain analysis firms and law enforcement routinely link addresses back to real identities by correlating on-chain activity with off-chain data points: an exchange KYC record, an IP address logged at the time of a transaction, an address reused across a public forum post, or a pattern of transfers to a known, identified wallet.

Because that re-identification is possible, and in some cases has already happened for a given address before your platform ever sees it, wallet activity generally counts as personal data under frameworks like GDPR once it can reasonably be linked to a person, even if your platform never itself performs that linking. A privacy policy that calls wallet data "anonymous" is making a claim about de-identification that the platform doesn't actually control, since the linkage risk comes from the public, permanent nature of the ledger itself, not from anything the platform does or doesn't do with the data internally.

The accurate version isn't a weaker privacy claim, it's a more honest one, and it's the version that holds up if a regulator or a security-minded user actually tests it.

On-chain data and off-chain data are governed differently

The second structural difference is that a crypto platform typically produces two categories of data that behave nothing alike, and a privacy policy needs to separate them rather than describe "your data" as one undifferentiated pool.

On-chain data is whatever gets written to the blockchain itself: wallet addresses, transaction amounts, smart contract interactions, token transfers, timestamps. It's public by design, replicated across every node in the network, and for practical purposes permanent. No privacy policy clause and no user request can delete a transaction that's already been confirmed on-chain, because the platform doesn't control the ledger. Off-chain data is everything your platform holds in its own systems: account emails, KYC documents, IP addresses, support tickets, session logs, and any internal mapping your platform keeps between a wallet address and a verified identity. That data lives in a database you actually operate, which means it can be corrected, exported, or deleted the same way personal data at any conventional SaaS product can.

This split is what makes a deletion request from a crypto platform user meaningfully different to handle than the same request at a typical SaaS company. The request has to be answered honestly, in two parts, rather than treated as a single yes-or-no.

A privacy policy that promises unconditional deletion of "all your data" is a promise the platform cannot keep the moment any of that data has already been written on-chain. The honest version explains what can be deleted, what can't, and why, which is also the version that survives a regulator or a technically literate user actually testing the claim.

KYC and AML verification usually runs through a third party

Most crypto and Web3 platforms that offer any fiat on-ramp, custodial wallet, or exchange functionality are required, under anti-money-laundering law, to verify who their users actually are before letting them transact past certain thresholds. In the United States this obligation flows from the Bank Secrecy Act's customer identification program requirements; in the EU it comes from the Anti-Money Laundering Directives, which brought crypto-asset service providers within the same identity-verification regime banks have operated under for decades. The Financial Action Task Force's Travel Rule adds a further layer for larger transfers, requiring platforms to collect and share originator and beneficiary information with counterparties, a threshold commonly cited around 1,000 USD or EUR depending on jurisdiction.

Very few platforms build this identity-verification pipeline themselves. It's far more common to route a user's government ID, a selfie for liveness matching, and sometimes a proof-of-address document to a dedicated KYC or identity-verification vendor, who runs the actual checks and returns a pass or fail result. That vendor is a data processor handling some of the most sensitive personal data your platform ever touches, and a privacy policy that only says "we may verify your identity" without naming the category of third party doing that verification, what data is sent to them, and how long the resulting records are kept is leaving out the exact detail a privacy-conscious user or a regulator reviewing the policy will look for first.

This is also where the retention story gets genuinely more complicated than most templates account for. AML law typically imposes a minimum retention period for identity-verification records, commonly five years after the account relationship ends, specifically so that regulators can audit compliance after the fact. That's a legal floor, not a platform preference, and it sits in tension with data-minimization and erasure rights under frameworks like GDPR, which generally expect data to be deleted once it's no longer needed. The resolution isn't a conflict a platform gets to choose its way out of: the AML retention obligation is itself a valid legal basis for continuing to hold the KYC record for that statutory period, and the privacy policy should say so plainly, naming the retention window and the law that requires it, rather than leaving the user to wonder why a deletion request wasn't honored immediately.

What this means for the policy itself

Put together, a crypto or Web3 privacy policy needs to do three things a generic template doesn't naturally cover: describe wallet and on-chain activity as pseudonymous rather than anonymous and explain the realistic re-identification risk, separate on-chain data (permanent, outside the platform's control) from off-chain data (correctable and deletable) so that data-subject requests get an accurate answer instead of a blanket promise, and name the KYC and AML process specifically, including the third-party identity verification vendor, what data reaches them, and the statutory retention period that governs how long that data has to be kept even after a user asks for it to be removed.

None of this is unusual as a compliance matter, exchanges and custodial wallet providers have been navigating it for years, but it's routinely missing from privacy policies built off a generic SaaS or e-commerce template, where none of these three data categories exist in the same form. Our Privacy Policy Generator includes fields for wallet and on-chain data handling, third-party identity-verification processors, and AML-driven retention periods, so the resulting policy answers what a user or a regulator will actually ask instead of describing data handling in the general terms a non-crypto business would use.

The information in this article is for informational purposes only and should not be construed as legal advice on any matter, and does not create a lawyer-client relationship.