thumb|315x315px|Ming dynasty (1368–1644) fuzi, decorated with emblems depicting the flowers of the four seasons. Held at the Metropolitan Museum of Art. A fuzi (Chinese: 拂子, pinyin: Fúzi), also known
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 0xee64aaa1c0dff259bc8f73a8eb7c2592dc49c9cc5883faed5d74069e4afef8ee. 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/4001b15c-13c8-4409-bd0e-ef3b684f2205.json and https://artists.proofprofile.net/proofs/artist/4001b15c-13c8-4409-bd0e-ef3b684f2205.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 0xeb116f5931e52381eb4b8a0a1b9e7503f8d5ff2eb50a22864bc5e80e20e5ceb7. Chain 2 (Bitcoin): anchored in block 958468 (2026-07-18T00:27:51Z), 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/TCJPJ1929866.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd162c4210d4f0e312b73b5753feb146cf1c2f87a274fd78b9f312fc710b7c573. Chain 2 (Bitcoin): anchored in block 956440 (2026-07-03T04:03:57Z), 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/TCJPJ1986350.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c2165ada047de91ff09a543d0d1e5db654d5200c149f2c2fc7ec973a77a8541. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/TCJPK2058487.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3c2165ada047de91ff09a543d0d1e5db654d5200c149f2c2fc7ec973a77a8541. Chain 2 (Bitcoin): anchored in block 956422 (2026-07-03T01:01:38Z), 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/TCJPK2058487.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xca3792490b1515ac89ef861da4276416e1dee8384ce77a9ca1f653fe096a5603. Chain 2 (Bitcoin): anchored in block 958104 (2026-07-15T05:34:05Z), 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/TCJPM2064919.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe1475cd545d477d4ecf764baac7c8fb57842d08a779db290b6e958863849178f. Chain 2 (Bitcoin): anchored in block 956304 (2026-07-02T03:55:08Z), 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/TCJPP2157413.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe1475cd545d477d4ecf764baac7c8fb57842d08a779db290b6e958863849178f. Chain 2 (Bitcoin): anchored in block 956772 (2026-07-05T10:01:46Z), 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/TCJPP2157413.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x32b5b01a28e7f68defa458983c9db244c043ae0fed4f6025092db3ca7510b109. 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/TCJPT2278434.