Yoon Hyung-joon (), better known by his stage name Hangzoo (), is a South Korean rapper and member of Rhythm Power. He was the winner of Show Me the Money 6. He released his first album, Best Driver,
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 0x7b7b5aba636f2db637c8a4448ed114814b1bb824da78c0e8a99b4bb8089a8734. 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/c21bef72-65a0-481c-b6de-c0041ceb901f.json and https://artists.proofprofile.net/proofs/artist/c21bef72-65a0-481c-b6de-c0041ceb901f.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
Investigation Couple, Pt. 6 (Original Television Soundtrack)
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 0x915527765a0a044a9e19ee0a1887a6a82455182e8c379cda628187a8ef0c31e8. 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/KRB141900023.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6de20a7be07fe264be0659d4f4686a120903ee7c89549446be2630e8164dfea2. Chain 2 (Bitcoin): anchored in block 956776 (2026-07-05T10:59:37Z), 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/KRF502500278.
She (Feat. Jung In & CHOIZA of Dynamic Duo & Hangzoo & Geegooin of Rhythm Power)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfb80c7ec00776f89d23f9563ff0f00feed31fc15e7461db516b2da6250f8b00f. 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/KRA381210878.
Directors (feat. Don Mills, Geegooin & Hangzoo)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x39661a685872810663b0bed13b10cb3ba4fc22714e28c01c48d5e8518a23a807. 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/KRA341519783.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x1c74523049969d841f77ad51dc08b54820dbb0af99be96f49581c5d72718203c. 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/KRA341417473.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x45a92946fa11664e6d853a656a0492b2b3909bc4730e7d199d441cbdd2f47c99. 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/KRC711800054.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe5281d5cac7a68486b712bb6ce2025b40548556047d316d6765fbd3569819ea6. 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/KRA491800263.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a6c15928cb1c41b2f567fe2071f36bc24834cf56cdcfcc5cf8fae448a43a64d. 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/KRA491700105.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a6c15928cb1c41b2f567fe2071f36bc24834cf56cdcfcc5cf8fae448a43a64d. 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/KRA491700105.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xad23261a1a41f26a0cd8dc91a3ceb1eae8248ece28bc0798c39ef4480de32484. Chain 2 (Bitcoin): anchored in block 956302 (2026-07-02T03:30:09Z), 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/KRA491700127.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc3e41883f56868f42f4792c102909a687c717c0cbde2cdf2893c864eb0966881. 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/KRA491700142.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x45034c6c4279da9ce3fc77d7382e7bee35af902d9cb4de56d075a9eced9cf04e. Chain 2 (Bitcoin): anchored in block 956312 (2026-07-02T05:09:12Z), 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/KRA491700154.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7bdbfca02063e25775bef39d843a2132e80e46d93c22e0d7bf8e07b29bb6bab9. 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/KRA491700157.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x404dba9ce165fe279ebfc83bd469b5f5974b661b3c1b15f60f6c084b9e866298. 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/KRMIM2100826.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf52badbc3015c4166b6d55fb3619640bf9a2fe7f05c8e03df5cc897529501b8c. 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/KRA491800324.
Welcome Back REMIX (feat. kaogaii, D.Ark, Park Jae Yoon, kitsyojii, Hangzoo, NSW yoon, CHERRY BOY 17, RB NINE, Benny G, TRADE L, Roh yunha)
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb1eae4b15c6737fd77d30e86bc48e59204bae494efc8d72f4d0c495c86c9f7e4. Chain 2 (Bitcoin): anchored in block 960144 (2026-07-29T21:09:47Z), 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/QM6N22423562.
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