William Bradford Champlin (born May 21, 1947) is an American singer, keyboardist, guitarist and songwriter. He formed the band Sons of Champlin in 1965, which still performs today, and was a member of
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 0xb9f9a1896a267a81ca4329d94ec70c5ff66771cdc903b540369a20463609e6c5. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/ff0a7bfc-6ac6-4634-8db5-6ea642743ef7.json and https://artists.proofprofile.net/proofs/artist/ff0a7bfc-6ac6-4634-8db5-6ea642743ef7.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 0x67bb86e49c442be5cb2360636d374e273d22dcfa139d8a7b444bf373a95142f8. 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/SEVVF1803601.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x412d6d046d4de59c1a9b6dd00670b3d211b3106edcd57e79e53ab01397e4ebbb. 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/SEVVF1803602.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7d1d90a13e404d1f95d65acdbc8d0d4931f4a84434e5253dad117ded9f7d39ef. Chain 2 (Bitcoin): anchored in block 959159 (2026-07-22T20:45:23Z), 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/SEVVF1803603.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3e494b46469291f8396b6c3677632d2c1c778fd35c8f03c8f4097c5546aa12b7. 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/SEVVF1803607.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa8e3306b24d7a78433c8c40840a699104cc57662e0f5684717475939f89334d8. 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/SEVVF1803608.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x75ca4ff495762d7da4482de6921bb7319ad056e4d44c4731320b187cfea3a8ab. 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/SEVVF1803610.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xacdcffed3cc58a378891088d10e5d7ef49e3c2fd29270f315051822c6530f285. Chain 2 (Bitcoin): anchored in block 960220 (2026-07-30T07:28:30Z), 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/SEVVF1803604.
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 0x13eb76c7a54ce039f11f2cac1354151a5edf62c37f7fa5f2920373321b4e4b45. 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/SEVVF1803605.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb1647ba939fe4f7a5523069153663bf702836aef73bac32183b4704b58b98f6f. Chain 2 (Bitcoin): anchored in block 960193 (2026-07-30T02:05:19Z), 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/SEVVF1803606.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xee42b7e99b91c1d4d98190e4038945a2e3ff41f4ed9343884e8a8cb00c6f72c5. Chain 2 (Bitcoin): anchored in block 960291 (2026-07-30T18:23:33Z), 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/SEVVF1803609.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3d07e4d2cdbfb1297e3f936ad79bfd6370927cb922ac59d58eef6318eebe3cd. 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/USEE10701817.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xd3d07e4d2cdbfb1297e3f936ad79bfd6370927cb922ac59d58eef6318eebe3cd. 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/USEE10701817.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x692fb39548ccf4ef24fc8dce19c509606bbc77241849c4144d4b7c16892d35b6. 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/QM4TX1849972.
Rock Steady - Zigaboo Version - Remastered
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x775cbccac7e6a54d8c314deb96fab8343ec4d7b71d0294305b8349fa3f641375. 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/QM7282056888.