thumb|upright=1.25|New York's 21 Club was a Prohibition-era speakeasy. A speakeasy, also called a beer flat, blind pig, or blind tiger, was an illicit establishment that sold alcoholic beverages. The
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 0x173b34cc6b2c848a5ee85ffbde6611b1ab36e662ae9914ea565fb0c1a2061fa0. Chain 2 (Bitcoin): anchored in block 953770 (2026-06-15T09:50:11Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9b478507-0fc8-40ea-95c1-61626842f3f8.json and https://artists.proofprofile.net/proofs/artist/9b478507-0fc8-40ea-95c1-61626842f3f8.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 0x9b3f9581f12466b2ed00cec8cf63de6c83cade94e12592cefac13aaac440c01c. Chain 2 (Bitcoin): anchored in block 956639 (2026-07-04T11:19:20Z), 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/ITUM72300998.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x56eec25e38dfaa6c3e99bd071d6ab11b00db771806def8dfe6bdf2c5fa9d86e2. Chain 2 (Bitcoin): anchored in block 958622 (2026-07-18T22:58:55Z), 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/ITUM72301197.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcad14594520392fd77356677bf675712cf152e9c594c7553591aecd5f1e8b5ab. Chain 2 (Bitcoin): anchored in block 958945 (2026-07-21T02:05:55Z), 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/ITUM72400393.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc42dbdbf81435924fb5bca383eef232ed882bbc75933182a1d6d1d7af4d013b9. Chain 2 (Bitcoin): anchored in block 958996 (2026-07-21T13:40:08Z), 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/ITUM72400423.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe71642e249064539fae5333570a8f610d9f1d3a3588be8c80e5b9dd54a5c22e0. Chain 2 (Bitcoin): anchored in block 958087 (2026-07-15T02:56:49Z), 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/US38Y2424226.