Privacy & no-KYC

What is a warrant canary and does it work?

Short answer

A warrant canary is a regularly updated statement that a provider has not received a secret legal demand. If the statement stops being updated, the reader infers that it has. It works because many jurisdictions can compel silence but cannot compel a false statement — though the mechanism is untested in most courts.

A canary is only meaningful with three properties: a fixed publication schedule, a cryptographic signature, and a recent external timestamp such as a blockchain hash proving it could not have been pre-signed. A canary without those is decoration.

Be clear about its limits. It is an inference mechanism, not a guarantee, and its legal status has never been fully tested. We publish one because the alternative — silence — carries no information at all.

See also: Warrant canary