The Arc de Triomf (), translated: Arch of Victory, is a memorial arch in Barcelona, Catalonia, Spain. It was built by architect Josep Vilaseca i Casanovas as the main access gate for the 1888 Barcelon
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 0x9b794ee1520b6b846a8411e5251cfd59131ad5dde882cf97bb5c9b0f614b4e28. Chain 2 (Bitcoin): anchored in block 953741 (2026-06-15T04:44:49Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/9fc66ef1-db69-4f56-bd51-b3780a27f2f3.json and https://artists.proofprofile.net/proofs/artist/9fc66ef1-db69-4f56-bd51-b3780a27f2f3.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 0x7d4d56f917e8eb75bfe13a7e27f3c632d538805ca412e191b37f258087377158. Chain 2 (Bitcoin): anchored in block 959002 (2026-07-21T11:47:29Z), 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/ES5952106546.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x76579247d04dc20467c37220f4ef0cd723c95e4dbc64515f6a4e93ec5ef4a5d3. Chain 2 (Bitcoin): anchored in block 958631 (2026-07-19T00:50:09Z), 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/ES5952206638.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xddc6513ab79303fa13081185d62b9195a27c4e1873a43892af62f1e4c4d7b478. Chain 2 (Bitcoin): anchored in block 956725 (2026-07-05T01:12:41Z), 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/TCAHZ2491867.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x30d9343597b4c04bd7446809d6acd891c39abc373b6ad1b725b7dbdbb3e962e3. Chain 2 (Bitcoin): anchored in block 958885 (2026-07-20T13:01:04Z), 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/TCAIF2462540.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xafc008040a468865d1799de7f6f28cf023405d1e98886966933dbfc14a5f9b8c. Chain 2 (Bitcoin): anchored in block 958585 (2026-07-18T17:05:16Z), 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/TCAJK2519871.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x018f2a2e4ff241e59ad9de92b9ae5b4e1fe17d9ce5c387dbdaeb5b311a27f75c. 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/ES62D2200029.