thumb|Irra Petina photo taken by Carl Van Vechten, 1948 Irra Petina (April 18, 1908 – January 19, 2000) was an actress and singer as well as a leading contralto with the Metropolitan Opera in New York
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 0xd923a0c788fe1775ac565d2926956b00c0cb6223924f8fc8fa6932b02cdc3eeb. Chain 2 (Bitcoin): anchored in block 954000 (2026-06-16T20:18:46Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/31aa3173-0282-45e1-a8f6-f9bd7696814c.json and https://artists.proofprofile.net/proofs/artist/31aa3173-0282-45e1-a8f6-f9bd7696814c.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Candide, Act II: Finale - Make Our Garden Grow
Leonard Bernstein - Soundtrack to a Life in Music
1. Confirm isrcCode identifies the recording in the pre-2022 source corpus and cc-db-prod record 2. GET OTSVerificationAPI → server-side canonical-record, hash, and attestation checks must pass 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. Confirm CopyrightID is the CopyrightChains transaction hash 5. If all match: the cc-db-prod record is independently anchored on Bitcoin at OTSTimestamp
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa33a549a49c56691f4d748e12a14d083a6a8cc84df34a08ffab49a1655b8dbe1. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), registered by our registry partner. The server verifies the private canonical record against OTSHash without exposing internal provider keys. Confirm the public ISRC, CopyrightID, and Bitcoin evidence via https://artists.proofprofile.net/api/v1/bot/ots/verify/track/USSM10213565.