BITCOIN’S MESSAGE-SIGNING SPEC TOLD VERIFIERS TO PASS SOME KEYLESS PROOFS — BIP-322 FIX MERGED — THE GAP WAS FLAGGED IN JUNE

On October 23, 2026, the editors of BIP-322, bitcoin's standard for signing a message with an address, merged a change to the steps a verifier follows. The old text said reserved NOPs and segwit versions above 1 make a check inconclusive. It did not name four taproot upgrade hooks: an unknown leaf version, the annex, OP_SUCCESSx and an unknown public key type. The author of the change, Ferdinando Ametrano, wrote that "a verifier that follows the text calls a signature using one of them valid."

Look at what those hooks do now. BIP342 says a script holding an OP_SUCCESSx opcode will "pass it unconditionally," and a key of unknown type gets no actual signature check. So a valid result on those proofs did not show that anyone signed with a key. A message signature is how a person or a company shows it controls an address without moving the coins.

The gap was raised on June 2, 2026 in review of a BIP-322 library for btcd, which is still not merged. Ametrano wrote that the library now returns inconclusive for all four. He ran its test vectors through btclib-wallet, a verifier he maintains. It agreed on three and called the annex case valid, as the old text said. Same spec, two verifiers, two answers.

The fix makes the spec version 2.1.0. A proof is only as checkable as the rules the verifier runs, and here the rules were the thing you had to trust. If a wallet, exchange or auditor shows you a BIP-322 proof, ask which version checked it. At the time of this writing, bitcoin was $80,847.