was a after Kankō and before Kannin. This period spanned the years from December 1012 through April 1017.Nussbaum, Louis-Frédéric. (2005). "Chōwa" in ; n.b., Louis-Frédéric is pseudonym of Louis-F
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → returns the Bitcoin block hash at height OTSBitcoinBlock; GET https://blockstream.info/api/block/{that hash} → its timestamp must match OTSTimestamp 4. Read CopyrightID inside OTSCanonicalRecord → must equal the CopyrightID above 5. GET OTSVerificationAPI → pre-computed 6-check result from server 6. If all match: this entity was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbce55efc6ec96054701ea53d240ecd28a304ec83c8f48920543ada3026b636ca. Chain 2 (Bitcoin): anchored in block 953674 (2026-06-14T19:07:16Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/5b8374f6-e636-49f3-97bf-b96e5f567d9f.json and https://artists.proofprofile.net/proofs/artist/5b8374f6-e636-49f3-97bf-b96e5f567d9f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).