Checkpoint may refer to: Places Border checkpoint, a place on the land border between two states where travellers and/or goods are inspected Security checkpoint, erected and enforced within contigu
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 0x35234ad767385b2094c0017df646223c2a58c57a6068ae8e2ceb616efba13cc7. Chain 2 (Bitcoin): anchored in block 954667 (2026-06-21T07:29:20Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d49ef9d6-9848-45f9-addd-e9e000ff976b.json and https://artists.proofprofile.net/proofs/artist/d49ef9d6-9848-45f9-addd-e9e000ff976b.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 0x13cf0c8f12a4bbcd5be9b9de44370e7a5e42c2d1f8af3f633cd2c3d40c879cca. Chain 2 (Bitcoin): anchored in block 958271 (2026-07-16T09:16:54Z), 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/SEYOK2328410.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2ca79ea08441017b5f584bf71787145cfbe3052dcbffc990f401151b153e2a2b. Chain 2 (Bitcoin): anchored in block 958943 (2026-07-21T00:27:37Z), 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/SEYOK2328411.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3ef95a4a5d0640ebbc9fd3d1f9a2845d0c4a3cca250d6c02c822fcf9d97d4b8a. Chain 2 (Bitcoin): anchored in block 958617 (2026-07-18T22:07:13Z), 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/SEYOK2328418.