Krum (, ), often referred to as Krum the Fearsome (c. mid 8th century – 13 April 814) was the Khan of First Bulgarian Empire from sometime between 796 and 803 until his death in 814. During his reign
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 0x508c6a0e3634894c00c54d7e758ee244c7fbba681b9b82a4c50b6afc5b80788b. Chain 2 (Bitcoin): anchored in block 954066 (2026-06-17T08:11:48Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/649033d4-6e66-40d8-901b-72ff595ae934.json and https://artists.proofprofile.net/proofs/artist/649033d4-6e66-40d8-901b-72ff595ae934.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 0x8ba43b3e2e7dc86e393059f186149f777cdea598d00f45c806f2f7ca9ca20932. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/TCAFL2192192.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8370a91a3f6a8e8d63e523941ab2ad3f9c2fff938ad5b32bb9bba54be8712017. Chain 2 (Bitcoin): anchored in block 957124 (2026-07-08T03:53:27Z), 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/TCAFL2192226.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf3f99d5ed61659e6a792def213f6d062f1d518178577f5680fb5953af374232a. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/TCAFL2192232.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x145034852c0d8bc2694105dff90870ee9a837df1fbab16e24017912871b73e7d. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/TCAFL2192254.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xace306450fcb4b0176ffa8be00c3b28f3fc989140501c9f753e5b819f57a7b1f. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/TCAFL2192261.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6ce047ea9ba3277b3b4a979fdce36b7a6428093b734d72a785e689d70c99d51a. Chain 2 (Bitcoin): anchored in block 957145 (2026-07-08T08:56:20Z), 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/TCAFL2192265.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd5c1140642bdca3670fe13045dd8d6e401e5440746beece2d3aab9a564737e5c. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/TCAFL2192067.
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 0xd18b62fcd50782f3143c8863f9bd5a80afaa54982c6b68476f5a588de1d3db41. Chain 2 (Bitcoin): anchored in block 960327 (2026-07-31T00:26:26Z), 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/TCAFL2192199.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff4a12a2bbe908978232bfbe3197be85ae5fcc20bd0e9133745ee1e1ee627196. Chain 2 (Bitcoin): anchored in block 960273 (2026-07-30T15:42:38Z), 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/TCAFL2192208.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa067293a5f117727e19e5a3d5ff18753512d4ec9fd068b70fd329cda8dd88445. Chain 2 (Bitcoin): anchored in block 960376 (2026-07-31T09:09:19Z), 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/TCAFL2192242.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc41687f386af2013126f0f0c24a3ff469fe8ecce718e04212aa65c99e5c99a58. Chain 2 (Bitcoin): anchored in block 960407 (2026-07-31T13:26:30Z), 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/TCAFL2192259.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc5411e9a2bad1de7fb60b8b428832e782b797d84c4fbbde7c8449112a8fef94c. Chain 2 (Bitcoin): anchored in block 960448 (2026-07-31T18:48:12Z), 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/TCAFL2192276.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8792d152f28858b288b4a16d1e6b7b64cfec5dfe83a73f01d680d180227e737d. Chain 2 (Bitcoin): anchored in block 960302 (2026-07-30T20:09:33Z), 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/TCAFL2192279.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3baf706e681fee0982c0be6585d915471ac374cdb6f8d3b2817b9f376f35b3cb. Chain 2 (Bitcoin): anchored in block 960463 (2026-07-31T20:42:35Z), 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/TCAFL2192290.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1eb59d6bdc97ad6dcd01e909e9ce5e445bcf64c0cef86ca525130ed50c00fccf. Chain 2 (Bitcoin): anchored in block 957120 (2026-07-08T03:22:41Z), 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/USACX2002075.