thumb|upright=1.35|Gravel (largest fragment in this photo is about ) Gravel () is a loose aggregation of rock fragments. Gravel occurs naturally on Earth as a result of sedimentary and erosive geolog
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 0xe5b56de3e98beaba9d814d1ccaadacac8cd1e4d45dff01bb5aa3845e0d4108b3. Chain 2 (Bitcoin): anchored in block 954342 (2026-06-19T03:22:39Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/86128c91-f24a-497a-a38b-d48ed0479afd.json and https://artists.proofprofile.net/proofs/artist/86128c91-f24a-497a-a38b-d48ed0479afd.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 0x4a80463f01efff51938fbd719441385ce0cecca25da345f3706086e24e7b290f. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/LTF760800001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfeb6f92faef612db8eea237e618d66d70292b97a7dc6a8ab686f14f925b627a6. 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/LTF760800002.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2e275ac7e193a39952a9a8ab9bb374890215bf01170fc9a2f171de11d61ddde0. 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/LTF760800010.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6500a947905f04d2a736974f944fba6060a38e9128c40565cd0f63449eda51e4. 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/LTF760800011.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x58825cf5516b21474ff69475ee969558c6a48be281dbc8360b4a9f48582042cd. 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/LTA260600025.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf4e88aa1c3b173bc64f02fdb773f2b815c5cdd2fef15ec73c5a1a397b614b6ff. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/LTA260600022.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e7c34c51617dc9bcda3348d62b83c9c00f210cf0c9b842c317611200262623c. Chain 2 (Bitcoin): anchored in block 957064 (2026-07-07T16:43:08Z), 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/LTA260600026.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x26152d5b00ac65f36eea02cb347b90411b88d5f03f5810775495b461f5a70b40. 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/LTA260600027.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3771bc1aa1453f1aa2e03b954c84d6eaeadc3f07bba81213d0418ab80d931a98. 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/LTA260600028.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6d7017100d61b149cf0c6297120ce436ecff74bf37fd63bf0077d051046e7b57. 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/LTA260600031.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1919e60b82652eda814cb59c2bda827b5edb622989000c9ce126134e3b4e54d8. Chain 2 (Bitcoin): anchored in block 960317 (2026-07-30T21:35:24Z), 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/LTA260600024.
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