thumb|240px|Bidu Sayão as Manon (Massenet), in the season of 1940 of the Teatro Colón in Buenos Aires Balduína "Bidú" de Oliveira Sayão (11 May 1902 – 12 March 1999) was a Brazilian opera soprano. One
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 0xfade810441df0f85fc9446017fa7d7ddeec03c06090f7281eedd0e959926c9f2. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/cfbc1661-eec6-4b00-bc1c-bc3b179cb87a.json and https://artists.proofprofile.net/proofs/artist/cfbc1661-eec6-4b00-bc1c-bc3b179cb87a.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).