thumb|William Billings grave memorial at the Central Burying Ground on Boston Common thumb|Psalm-Singer's Amusement by Billings, "printed and sold by the author at his house near the White Horse, Bost
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 Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e6a258ec7df497e67fad8ac400c30abfba5bcd22271625bcadf81dc36b7fa6d. Chain 2 (Bitcoin): anchored in block 953674 (2026-06-14T19:07:16Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/6156df5b-c674-4f73-ae1c-259bd71a038e.json and https://artists.proofprofile.net/proofs/artist/6156df5b-c674-4f73-ae1c-259bd71a038e.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Early American Choral Music Vol. 1: Anthems and Fuging Tunes by William Billings
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 Note: an OTS proof may carry multiple Bitcoin attestations; OTSBitcoinBlock is the earliest confirmed one — a later attestation inside the proof corroborates it and is not a mismatch
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x61aacf6dc71693a27f534e829ea9652523cd18a5282daf17cff18efa20324d18. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), 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/USHM19104812.
Easter Anthem "The Lord is ris'n indeed"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xacdd6a599e2c76f573e5e6209704c37e391f948576f13477865b279d99369cb6. Chain 2 (Bitcoin): anchored in block 958846 (2026-07-20T08:14:15Z), 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/USHM19104816.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x54dce89908b8a1d286192469508af855480e8a63346041b0968df75f480c4950. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/USA4N1301429.
United States Air Force Heritage of America Band
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd7e2294e59d3ebd9de94c0408270c92cad173e749df3e5fbf21c90b82247aa78. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/USA5R1134608.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x087f35d3df1e01eca5f24bba82afc82ff9a0e99ce9580be4b8562197a7d6de06. Chain 2 (Bitcoin): anchored in block 960327 (2026-07-31T00:26:26Z), 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/USB8U1059074.
Billings: The Singing Master's Assistant, 1778: No. 6, Judea, "A virgin unspotted"
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb7943642c0dbfd6bc70e7f141bee1a0fa6a4b126952903b5f9e9f0c44266c492. Chain 2 (Bitcoin): anchored in block 960418 (2026-07-31T15:20:15Z), 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/GBAYC9100784.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfc8ed31957a3304348dbf04f6fc273053147d93cb451c75e3b0333b10599794a. Chain 2 (Bitcoin): anchored in block 957118 (2026-07-08T03:20:19Z), 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/DEB339870109.
Thomas-Town ("Great God, how frail a Thing is Man")
Early American Choral Music, Vol. 2: Anglo-American Psalmody 1550-1800
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd2324579dcc457a074336ed0f05c38bffe9f720ac2ab5ba083ac0ebef7112fd. Chain 2 (Bitcoin): anchored in block 960509 (2026-08-01T04:30:37Z), 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/USHM19612809.