ESRA may refer to: European Safety and Reliability Association European Survey Research Association, founded in 2005 to provide coordination in the field of Survey Research in Europe École Supérieure
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 0x4369eefba01fd200cac23552a64fc15708d4de9b05efba03f1441ece6f49e6d8. Chain 2 (Bitcoin): anchored in block 953697 (2026-06-14T21:49:28Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/72de7586-30bc-46b7-8bdc-1f7304c292a7.json and https://artists.proofprofile.net/proofs/artist/72de7586-30bc-46b7-8bdc-1f7304c292a7.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).