Tobruk ( ; ; ) is a port city on Libya's eastern Mediterranean coast, near the border with Egypt. It is the capital of the Butnan District (formerly Tobruk District) and has a population of 120,000 (2
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 0xa9f1b504348cb170f5837b6e4fe438288d5f16740c54768f822f534576d68e68. Chain 2 (Bitcoin): anchored in block 953701 (2026-06-14T22:16:40Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/765e1295-956f-4371-aeec-643c4383ee30.json and https://artists.proofprofile.net/proofs/artist/765e1295-956f-4371-aeec-643c4383ee30.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 0x9255e55c3720b4964a6739ac1c9218ad9824446705cc09ab12f128ccf39b5b9e. Chain 2 (Bitcoin): anchored in block 956474 (2026-07-03T08:56:35Z), 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/FR6V81577158.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7699b745a3d4f6fa53e0205cf6e34ee4c09aec5fcb3d3cad0bdfd69b6c78e484. Chain 2 (Bitcoin): anchored in block 958169 (2026-07-15T16:16:18Z), 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/GBKYA0703285.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd8df242b3f0373c48fd8e0f0d7b5fe27da55d276663ba358273aa1ad7cf9e77f. 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/GBKYA0703292.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3858268a48d2a5f20edbfb4d065ca8a9970bdb32f417e9c7b79c0b232ed5b5a2. 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/GBAJE8300076.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe061f1aa1a2fa8388f73b8de26a2b58dd2c87559ddf321601109c2a54a426657. 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/GBAJE8300174.