Serko Limited, known as Serko, is a travel management and expense technology company headquartered in New Zealand. Serko was publicly listed on the New Zealand Stock Exchange in June 2014 and on the
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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x96a6056a91e78d81ad8928212279025181f74a3dcf8a79c8cdedb70a4d9a2e81. Chain 2 (Bitcoin): anchored in block 953423 (2026-06-12T21:20:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/1d909672-4000-4846-b947-8ca8ff1346a5.json and https://artists.proofprofile.net/proofs/artist/1d909672-4000-4846-b947-8ca8ff1346a5.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
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1b6eb2c9949b97325702e37bc5112533d93be9b7b522d9aa894a3dd81eb83997. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/QZTVM2346643.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x565f20a1a8082eb7bd75de261d7169f226c54e0d70cf6dd313221853cda41247. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/ES71G2014467.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfcb54dd5c0ebeda54e2e4fc06368e9314d17ff11918a3d5bf5440ccd72994bfe. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/USA2P2435293.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a87701efd519e8d2d557ef76e785e084fd56b522bc710ff69124ad67e1b1c81. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/USA2P2141521.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xddd73051166936bfe9d8e6a9204da9bdd405789aac396a1599038949ae2e9e75. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/USA2P2340369.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd13afc81794480a5015c2382bc928c1f4e570b1269297e1c211e1dcab49d609d. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/USA2P2320455.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1e08d69652b95910ab1a7f328d4beee47c1cc87fa7d9f14dc4784408512536e2. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/USA2P2332630.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x177f97e3045ef59e979f6f0905bfc5fde33d18a4ed249e251cb3855624569fe6. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/BK4DA2321680.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x81caa5b7e5ddc6d08c03df030f885c71ef03f890e882c3b644cc5ad88726152a. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/USA2P2210226.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x48f75450b97d4790ad61fc2c9da09947a83bb57dde40b3600957c283645bf3da. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/USA2P2222656.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xef626d064cb9f147d3d4a48f4363e311df311e0ded964dcd9118004fed64736a. Chain 2 (Bitcoin): anchored in block 953513 (2026-06-13T12:47:07Z), 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/QZGLS2414489.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa73bdab9851095e027bb726edfb8e4700f7aeacf0c5a033434b2b20dd9c28ef4. Chain 2 (Bitcoin): anchored in block 953536 (2026-06-13T17:25:41Z), 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/USA2P2117375.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x736f95748e944c1cfc85f9836ad9c3a06e906b83b9198d08b80fa968aa0aaf49. 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/USA2P2100168.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4315fdb4efd091aa35392194ff8568220936892697c4857dd198f1924a569b6a. Chain 2 (Bitcoin): anchored in block 953528 (2026-06-13T15:41:10Z), 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/ES71G2061154.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0524682425fee37ec3f7b980717c66ccfa8110acee95acf2c1a0105bbdb7dd72. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/ES71G2061547.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf1d72168e0d228c7c5f5e4a17ab479641d0a406f022e8974ba36fde462774a91. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/USA2P2100169.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9141ba2b137f52e546684af115d563d8eb6cc08eb498ef934e2f51de1bef098b. Chain 2 (Bitcoin): anchored in block 956889 (2026-07-06T06:56:49Z), 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/USA2P2100170.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x45019cd3b46155de457ff4a5f32882b0af9ea7a88476d092a7c800428e14962c. Chain 2 (Bitcoin): anchored in block 953520 (2026-06-13T13:32:09Z), 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/USA2P2100171.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0524682425fee37ec3f7b980717c66ccfa8110acee95acf2c1a0105bbdb7dd72. 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/ES71G2061547.