FF.C (Fortified Concept) were a Greek hip hop group that was active from 1987 to 2005. FF.C fused hip hop with rock. History The group was formed in 1987. Dimitris Petsoukis was experimenting with
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 0x05d5a1ecf43e28f350eae98c5e3f69a11e768138e8e46a36b64921f9d102b4f4. Chain 2 (Bitcoin): anchored in block 953407 (2026-06-12T19:24:56Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/4f60919f-137a-4198-a223-3dc59e3f868f.json and https://artists.proofprofile.net/proofs/artist/4f60919f-137a-4198-a223-3dc59e3f868f.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 0xfa94848d921ba71e6ea5583be8dc8fee00d08dbc75e40959373f5de9d582c939. Chain 2 (Bitcoin): anchored in block 959100 (2026-07-22T05:29:55Z), 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/GRP010063897.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe189bf06729b29e688331bec180d531f3998afc532802ef1ac775cc3bdf459c8. Chain 2 (Bitcoin): anchored in block 958720 (2026-07-19T10:53:46Z), 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/GRP010064097.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2dc72d34fd1e09051987b89d7af5229508f1b9c26e784980c484b4d08f575ce4. Chain 2 (Bitcoin): anchored in block 958662 (2026-07-19T04:43:15Z), 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/GRP010064497.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5bd37c03f049458a746225bfd4085294e0d149b3b0cd01bad2126f35f06c935a. Chain 2 (Bitcoin): anchored in block 958238 (2026-07-16T04:30:31Z), 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/GRPO19800749.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa1cf5b8c76d9e3623502bbf6cd53b7dc1b3977742b38ed41b6139b4e86cf1075. Chain 2 (Bitcoin): anchored in block 956375 (2026-07-02T16:51:38Z), 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/GRPO19800753.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc1df0615c75dc73df95474af9ad99dba8813acd356867e108027cd9aaddafd34. 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/GRPO19800754.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x00931f10a992bfcbcc69fa9edfa1341b86da68217c6be4435e39fda0e319577f. Chain 2 (Bitcoin): anchored in block 959034 (2026-07-21T16:34:25Z), 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/GRPO19800758.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xea829ee5a57d38fdcc8b9eff931831a7caecbf33d7be522c3b6ee3a24c864dd5. Chain 2 (Bitcoin): anchored in block 958447 (2026-07-17T19:47:19Z), 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/GRUN10200056.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb041da4dc786a2719379e6e8f7c06f3748b58edeae11d2bd61b2d3421e35378e. Chain 2 (Bitcoin): anchored in block 958245 (2026-07-16T05:50:22Z), 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/GRUN10200059.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6b1ef6fc41f616becec7821dba97cc2e20eb6fc8ff69f77d67118c6946baffae. Chain 2 (Bitcoin): anchored in block 958969 (2026-07-21T04:58:13Z), 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/SE6A91805630.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x86fbe161385d960cbffa33cea59899b764d08255b13d62393df2fabf45869947. Chain 2 (Bitcoin): anchored in block 958931 (2026-07-20T21:15:01Z), 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/SE6A91805632.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcb7e7d91adbe13da1849f461f1eb4fe84a321a109f834408dc94b02bdff11afa. 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/SE6A91805633.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7aa5042d40b2e0f9dc4d06b668ced3712f71bc05ab23b5ece3e6d17f52448a69. 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/SE5751822833.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6ca042f28cb962e06041fcbdc4956f7fddc26d57d00fff7b1d023955982298c3. Chain 2 (Bitcoin): anchored in block 958959 (2026-07-21T03:51:22Z), 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/SE5751831372.