An Chil-hyun (; born October 10, 1979), known professionally as Kangta (), is a South Korean singer, composer, songwriter, record producer, actor and radio personality. Known for his work as a member
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 0xe11c06641889fec7b1d5e1a4b064132e3a53e855a2aab8a648cf4e787f34b3a0. 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/1f817fd2-5c09-47a5-95b1-2c9ccb9b9992.json and https://artists.proofprofile.net/proofs/artist/1f817fd2-5c09-47a5-95b1-2c9ccb9b9992.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 0x68ec03c1383f9b7a907ed5302553264ed6ea1d6f88356ea4c800180b4b901b03. Chain 2 (Bitcoin): anchored in block 956711 (2026-07-04T22:48:52Z), 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/KRA300803220.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x454fccdd3777e20a574a82f45ef14be96853ee62ac3a9a8b503c9ff123ddbac9. Chain 2 (Bitcoin): anchored in block 956634 (2026-07-04T10:04:33Z), 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/KRA300800491.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf98e2a454f3fae3db718115d421d61e93a5b29fc2933273233a2a9766557f74f. Chain 2 (Bitcoin): anchored in block 958951 (2026-07-21T02:01:41Z), 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/KRA300800499.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6b97788789483002343936d1c31bdcfddbdeb27aa196dc2d201d29c633de27c5. 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/KRA300800510.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf610797104f2589ef2d618034c09a565f11515dcb0186c6f222d0373d90f153b. Chain 2 (Bitcoin): anchored in block 958942 (2026-07-21T00:24:07Z), 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/KRA300802992.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xed534750e65a35f04a304e7580e4683200eb179f0cb9ae8a06f121ed24636125. Chain 2 (Bitcoin): anchored in block 958975 (2026-07-21T06:12:52Z), 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/KRA301600376.
Theme Of Prontera (From "The Memory Of Ragnarok")
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc674b1b3ca55a664106b6803d7ca227c47f81873095f038ec0c9ac2f0cf4597a. Chain 2 (Bitcoin): anchored in block 958137 (2026-07-15T09:47:57Z), 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/KRA301700261.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8f66a919358f5770a533ad39360887dce51c6de726ed9e0e01a92aaf2f3700bf. 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/KRA301700262.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdd3111b1add0ddc7ffc2ef96a827bc9b18ffbcb8d3693fbe50c3effe555dd24a. 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/KRA302100014.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d8089abfca004d0aa35f7a35a0d5b8ab4634cb34b509831908b4987392d03c4. 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/KRA302100077.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5169142e7161e02194cb70e24a41945a22b8b6a9f0c53d1ac271286f0d025d2b. Chain 2 (Bitcoin): anchored in block 958607 (2026-07-18T21:01:11Z), 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/KRA302100234.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x48fa7374e425c675fdb599695cc75750b5ae06ba47e6c777dfd500c602e5d7d5. Chain 2 (Bitcoin): anchored in block 958917 (2026-07-20T17:53:56Z), 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/KRA302100298.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbfbffd710557eafa3a528cf0fbb37c860a31c76da416390f29230886e17f00a2. 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/KRA302200005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbfbffd710557eafa3a528cf0fbb37c860a31c76da416390f29230886e17f00a2. 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/KRA302200005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbfa3d3c53d488f68cbbbb0ea034508fe74f1e32f2b82ac2252bfd030e9a49500. 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/KRA302200273.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcf20f2f13ffe0cb3e36a511e1835163a787695f46a17f8826241406e2f2df151. 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/KRA302200279.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x85a15196548796fcbaeb27e7d5fa70ef3ecc324ce7fea7bbd4c1b35d53784e4b. Chain 2 (Bitcoin): anchored in block 960138 (2026-07-29T19:35:34Z), 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/KRA300811709.
지난 여름밤의 이야기 The Memory of last summer night
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe0a4260f250198c543d6756b6038223eca7699b4ba664a7ba0a6f7665c0184f4. 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/KRA300802895.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc52254cb3205e60ba7d4703c6cbb0cdd82a28059697abdf50f8c030778ac04ab. 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/KRA300802763.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0b69f8faa8fde4c6968c2108e25d2f4db5d2a7fa9a132da432b6d8ae8830e424. Chain 2 (Bitcoin): anchored in block 960209 (2026-07-30T05:15:54Z), 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/KRA300801034.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x037d883c36ee3804a88c5482f15c4dea0deffcf6ae06d974bcf29ca754682df0. 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/KRA300800742.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc92ebe51d74be3e655480bcc5f418f26940f0f5905ffa31eb717ed715ca7c792. 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/KRA300803010.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e949104989f004e52b263f4bf224e1c11db132b71cdedbc7dffeddd4b9f2e80. 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/KRA300802939.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9fb61ea68e8a1f8e5b4926674f19e537e08f9b030ff9fccd3e78aa6868c87f7d. 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/KRA301700578.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x66222b91e39269adee1d7b2218e166dfe6f40ca6cce8fbf425e012a09c139677. 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/KRA301700579.