# Double SHA256 Brainwallet

More rare form of brainwallet with secp256k1 key derived by `sha256(sha256(passphrase))`.

We expect that some of the newer `bc1q`-prefix addresses are deliberately placed canary wallets by other researchers to observe attacker behavior. A noticeable characteristic are small transfers with 300, 500, 3000 Satoshis and so on.

The Bitcoin addresses represent compressed and uncompressed public keys.

Due to the nature of brainwallets, the collection is not exhaustive.