upright=1.35|thumb|Otto II is crowned as Holy Roman Emperor. Year 973 (CMLXXIII) was a common year starting on Wednesday of the Julian calendar. Events By place Byzantine Empire Spring – The
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd1d45c5590d5d677dd901758f2a5fd757fb592edec61c1688585584ee7c3f130. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/8246895d-563b-4dde-89df-48efc3d88af2.json and https://artists.proofprofile.net/proofs/artist/8246895d-563b-4dde-89df-48efc3d88af2.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).