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OC Stamp

Sign anything. Anchor the moment to Bitcoin. OC Stamp binds three things into one envelope: authorship (BIP-322 signature from a Bitcoin address), priority (an OpenTimestamps proof chained to a specific Bitcoin block header), and optionally stake at signing (an OC Attest attestation reference). The result is a self-contained .stamp envelope that anyone can verify offline, forever, without calling ochk.io.

Who this replaces

OC Stamp was built to be better than the adjacent-and-broken incumbents:

IncumbentProblem OC Stamp solves
PGP / GPG signaturesNo block-level priority anchor. Keyserver rot. Web of trust is a tarpit.
OpenTimestamps aloneProves timestamp only. Says nothing about authorship.
C2PA / content credentialsx509-based vendor PKI. Trust hierarchy reintroduces gatekeepers.
EVM notarization contractsWrong chain. Per-stamp gas. Subject to reorg.

Stamp borrows the best bits — OTS for anchoring, BIP-322 for authorship — and nothing else.

Use cases

  • Release / commit signing via a git-stamp plugin (one stamp per release tag, anchored before public announcement).
  • Long-form publishing (authorship + "written before X happened").
  • Legal self-notarization (no third-party notary; Bitcoin block time is the witness).
  • DAO proposal authorship (the signer of record is cryptographically bound, not just the wallet that submitted the tx).
  • Sybil-gated content feeds (combined with an OC Attest reference for stake-at-signing).

What it proves

A valid Stamp envelope proves:

  1. Authorship. The envelope was signed (via BIP-322) by the holder of a specific Bitcoin address.
  2. Priority. The envelope's ID was committed to a specific Bitcoin block by a specific height — so it could not have been fabricated after that block.
  3. Optional stake. If the envelope references an OC Attest attestation, verifiers can resolve the signer's sats-bonded × days-unspent at the moment of signing.

What it does NOT prove

  • Humanness. Same as every other OrangeCheck protocol.
  • Exclusivity. Someone with the same key can produce multiple stamps for conflicting content. Priority is per-stamp, not per-signer.
  • Non-repudiation at the application layer. The cryptographic proof is solid; what the signer meant by it is still a judgment call.

Section contents

Packages

  • @orangecheck/stamp-core — canonical message, envelope format, stamp(), verify()
  • @orangecheck/stamp-ots — OpenTimestamps calendar client + proof helpers

See SDK overview.

Shared ecosystem concepts

Spec + implementation