Delta commonly refers to: Delta (letter) (Δ or δ), the fourth letter of the Greek alphabet D (NATO phonetic alphabet: "Delta"), the fourth letter in the Latin alphabet River delta, at a river mout
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 0xc9ddfbe24a4763c2f98813233ef50a0fc1ef3653448269ee680f08b736a31e03. Chain 2 (Bitcoin): anchored in block 953778 (2026-06-15T11:57:35Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/b81cb3a9-b69e-4399-b503-2d3f124b97ef.json and https://artists.proofprofile.net/proofs/artist/b81cb3a9-b69e-4399-b503-2d3f124b97ef.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 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 0xb48b4fe568ccef5572f601a533400a64e7d9bbef9dbfe66c924528c087366504. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/FRX282224118.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7f8dad32dcaacfc2875c9aff24c7327107975432887e0cb722a6f8e3b4fb5298. Chain 2 (Bitcoin): anchored in block 958316 (2026-07-16T19:42:29Z), 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/ESA092321216.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa0911fb67b8d9830820c690a15db3cb906c20b4c2f946be8600f90155cf6b496. Chain 2 (Bitcoin): anchored in block 956422 (2026-07-03T01:01:38Z), 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/ESA011640411.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd31f1ce07e56318d69049303208da18e556d5427b3f00e49c60ead63c5b61873. Chain 2 (Bitcoin): anchored in block 959088 (2026-07-22T02:14:33Z), 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/ESA011836988.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb20c36f35370d74b5db7f36dfdaa720408d628ac09a96971658313fe9d3a9f30. Chain 2 (Bitcoin): anchored in block 958316 (2026-07-16T19:42:29Z), 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/ES71G2427485.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf70ed426bd1647d17ebcf50ebc368d3c86cc97fd1b0d5ca4cfe1ca67f80a523e. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/ES71G2432868.