Kristian Konstantinov Kostov (; born 15 March 2000) is a Bulgarian-Russian singer.He has a double citizenship: Russian and Bulgarian.Sources:1. Quote: "17-летний участник «Евровидения» родился в Москв
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 0x3a4a3b1e15390cae03571d94b751d31dce402f017d5496043c780615d753a810. 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/0decd984-af37-4da9-b155-b0e416993280.json and https://artists.proofprofile.net/proofs/artist/0decd984-af37-4da9-b155-b0e416993280.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 0xa04273ce34060db57163c853066d515bfa0d7ad88a5e2b904dd03fa11c59485d. Chain 2 (Bitcoin): anchored in block 958286 (2026-07-16T12:43:37Z), 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/BGA271500036.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2dc6b8375ab0312b9bfa438f11d0ca85815605b628c63e9faeac51340b47905b. Chain 2 (Bitcoin): anchored in block 958832 (2026-07-20T08:20:52Z), 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/BGA271700001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x77eebaae6619bdd91e6ea2d8c985059735595b3e06f400e3ec337e68dc383518. Chain 2 (Bitcoin): anchored in block 958728 (2026-07-19T12:24:55Z), 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/NOQR18010101.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x436eb7b83f66395ec7ba5524f00e59878b0ac466c1b89831d9bdcd1efc38032d. 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/ATUM71800092.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x73cd8d6d401221571f86cb87a859202c44007b14300281f415c3b6d924b527f3. Chain 2 (Bitcoin): anchored in block 956576 (2026-07-04T02:06:47Z), 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/DEUM71803203.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4921448ce5677f15222590cc3618dea41aca490740bda97970bf80798faa35be. Chain 2 (Bitcoin): anchored in block 956484 (2026-07-03T10:47:44Z), 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/DEUM71803205.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8a96b79d3ba60175f05b1717985b8309123d5448cadeb0f9fcfb0a042b4f805e. Chain 2 (Bitcoin): anchored in block 957880 (2026-07-13T16:39:18Z), 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/DEUM72000431.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x90df3455f15a83fd5756f1a63c70925a1ae6391c397aee4477d9828d6b0f74f9. Chain 2 (Bitcoin): anchored in block 956728 (2026-07-05T01:43:49Z), 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/DEUM72000234.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x19f2ab22d6ba36d4eef87b243d5e98314609d1082018d96ba8bafe27e850fe31. 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/DEUM72000231.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcad89cb455e8c43e3400fc0ab25fec647106b20f780c97ef1f75110a94bbae97. Chain 2 (Bitcoin): anchored in block 958538 (2026-07-18T10:30:13Z), 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/DEUM72000229.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x62600e786aaa286fb8ecd71da09e59026083e2cc5d6cd4df0c9a9766ccd63df2. 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/DEUM72000230.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x442abb76c88c6b8fa1f58ab149a63bbd2da6344e9d8cb3dcbbb8be9af790758f. 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/NLRD52302245.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x549c20602437a8c41311fdb0d0cc097a1e7989e19346a61186fafa2ecc546b48. 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/QZK6K2497039.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd3781360dfd0c5f2af0f8b2d47392a8694f9d70e3ec71f1d4a38a0870a0cc87. Chain 2 (Bitcoin): anchored in block 957819 (2026-07-13T07:53:33Z), 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/QZFYX2366030.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9a7d85dde17654bdab1414b82b2e62e5d5e94428e99e43ed7913ad4078531719. Chain 2 (Bitcoin): anchored in block 960231 (2026-07-30T08:33:28Z), 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/FR10S2191651.
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 0x41ef0dc7becc3b280e9476923722f76f8afec926a53058986ff9e4677417b8ef. Chain 2 (Bitcoin): anchored in block 960403 (2026-07-31T13:04:34Z), 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/FR10S2191687.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d224c71aaf180d86fa8b2054e2361c12420498525ca632132be992434dc5470. Chain 2 (Bitcoin): anchored in block 960177 (2026-07-30T00:21:01Z), 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/FR10S2191640.