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 0x76be4e7a90987d471a84a81abe16e8f331fd6ad1d984940258aa544ed9ebc03b. Chain 2 (Bitcoin): anchored in block 954065 (2026-06-17T08:10:43Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4a0a4467-f7df-4ec7-ae86-ac20441533a9.json and https://artists.proofprofile.net/proofs/artist/4a0a4467-f7df-4ec7-ae86-ac20441533a9.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Nueva York: A Tape Documentary of Puerto Rican New Yorkers
Sounds of My City: The Stories, Music and Sounds of the People of New York
An Actual Story in Sound of a Dog's Life
You're Stepping on My Shadow, "Sound Stories" of NYC
Tony Schwartz Records the Sounds of Children