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 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 0x63c7b016620416a90e3e5486da7e2f5e8ad0a5254d994ef8321879a2cd82bad8. Chain 2 (Bitcoin): anchored in block 953791 (2026-06-15T13:40:30Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/dba5ad16-eec1-4a2c-9bc0-faaca62e0ca9.json and https://artists.proofprofile.net/proofs/artist/dba5ad16-eec1-4a2c-9bc0-faaca62e0ca9.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 0x2fe87eb6cac5cfaad4ee0edf1f115e049898c9d4b21fd88c6bf9192a0fe8d875. 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/BGA262259499.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa66803cf7590a261c55025a1b538ec8f5ee979d73af6deace75e4d7c0851d24d. Chain 2 (Bitcoin): anchored in block 958121 (2026-07-15T08:02:12Z), 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/BGA261577708.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2028d1adf41a45e5c28dda54baf1b898b951dd5004200c9724b0cbc8050a32cd. 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/BGA262258499.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x485d86e558861148b72e01f3ca85cc87e00e3026628999a40b05e70ff90cd45c. Chain 2 (Bitcoin): anchored in block 958935 (2026-07-20T22:08:19Z), 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/BGA261577706.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb2201c8b57912a34b3ead60e28b00a1da22402b49976cb2a64d52575432e0f43. Chain 2 (Bitcoin): anchored in block 958208 (2026-07-15T22:40:25Z), 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/BGA262258399.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe7a5b690660e36521ff4811ffc856bd00e871b152951c39bcefbfb1d60c5e509. Chain 2 (Bitcoin): anchored in block 958351 (2026-07-17T02:38:05Z), 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/BGA262258799.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa27c72b96a7859229d133db3a0ab03b2c05a33b9235bf1dfdf29a191fe71170d. Chain 2 (Bitcoin): anchored in block 958448 (2026-07-17T19:49:21Z), 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/BGA262258899.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x86426a3bfe634a343be6a82b67b8d4e31195fc75b36073db53f7f010dd15b57e. Chain 2 (Bitcoin): anchored in block 958489 (2026-07-18T04:13:26Z), 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/BGA262338052.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x33ac9b0b6228752fe8f601fcfb17383c0c1b6a3d2acf34c4b8fe1db52d1f4505. Chain 2 (Bitcoin): anchored in block 956545 (2026-07-03T19:59:51Z), 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/BGA262404515.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9d2e872b0d77153ca01894e108c20e099ab2389bc81558adcaee71503a290067. Chain 2 (Bitcoin): anchored in block 958650 (2026-07-19T03:36:41Z), 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/BGA262405076.