thumb|right|upright=1.3|A modern claw hammer suited to drive and remove nails thumb|Cartwheel mallets with heads of felt held between steel washers for use with timpani drums thumb|Detail of the head
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 0x22bed1f218a1f5fa3bf609ecd6bb978adc40e72afce46aa4bf0fff49f7971bd2. Chain 2 (Bitcoin): anchored in block 954513 (2026-06-20T06:31:18Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9f5fe557-cb18-4abc-bb92-46ec38959abf.json and https://artists.proofprofile.net/proofs/artist/9f5fe557-cb18-4abc-bb92-46ec38959abf.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
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 0x84415f0c6ae27a41a53a58ffe0c725cde91acd4ef9aa084eff609a61c74b45be. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/QZW9L2384154.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x36165cd20f96ca6dd150350cd37a79d1b685dc8974bf32652e9f8a66fdd4a366. 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/US38Y2403865.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe56d551ad86e4a8c305f063b87a6aef5fe1ca41d83a543c2a832a11fa8e726c2. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/USP6L2100982.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb1eee9eefe879592cc6584a6b977d5c33225df59562972c89ca8f2323d7c6515. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/USP6L2201096.