Kiefer is German for jaw(-bone) or pine tree. It may also be a variation of the German word Küfer, meaning cooper. As a surname Notable people with the surname include: Adolph Kiefer (1918–2017)
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 0xe41edb1de2327963cc6dfa16c02ac4913469a5f4f30355d8555e33d701b5f12b. 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/fcca7803-0606-4d40-b3ad-37bc0e633454.json and https://artists.proofprofile.net/proofs/artist/fcca7803-0606-4d40-b3ad-37bc0e633454.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 0xca1a4aaf282e38759253dd90b91f22aa6a6bce2d838edfd9f54e64f35a7f3a73. 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/US2S72221051.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x83fd765a8c638c0e483f6d261f10588f5c692646409510557f185a95aa52e317. 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/US2S72221052.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe61fa6de4a92eaee6bcb19897bf632fa1b459401aab5e5019879182a08e1630a. 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/UKJLR1700317.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6e3596e4b47c013df4a95c42d90378a1da5cd5d11e252a041ca814ed08981646. 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/USLD91737227.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x58cf452d0de2241f7757b715cd609a2084c653ce70809d6c8b1191bfaa76f54e. 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/DGA0H2317442.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x814daf5fc5271e4641346ee05dccf3d42d04101b51f00c276281233e115bfe08. 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/QM4TW2478509.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x670f58a1cd87b9cf6cb3b0fc4be5c589c300a4635ee13bdda305c47af05d9e61. Chain 2 (Bitcoin): anchored in block 953515 (2026-06-13T12:53:06Z), 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/QZFYW2175363.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x245257b919c3914c6d5b99b2c6df5a2a0b5dc8abf82212790cab1e52355defef. 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/US2S72496001.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x27ff7a9f3916cfaca06772157b46a8953b6d09db566b52271a083c2f992960ea. 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/US2S72496002.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x89d15d4c03b33a47d084a2a3ec2496bf4bd80ed4a7dc34dc1875761a2d0941fc. 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/US2S72496003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe75a75b7bc75d429fdffb048a33b350a0eefd19695816d0331ebee305f4d75cf. 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/US2S72496004.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xdb8984378560dceeef62fbcc8c41f673e9f2259185711ba2ecfc6a32fb42ea2f. 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/US2S72496005.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7a933471d1839686cef170bbd129d681d34903522bfab512072a2af9cb208306. 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/US2S72496006.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8d2ceaa2e4929bdae35c30967eef03200fb258fc2193454f296346ca8291fca7. 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/US2S72496007.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x51735a0061798cdbc04d3daae85bdab2db754cfbe487d386b16774633f92c72d. 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/US2S72496008.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8d2ceaa2e4929bdae35c30967eef03200fb258fc2193454f296346ca8291fca7. 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/US2S72496007.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe861f05244870af1bcc8da71dd9783bf0533219148481ee12ef9406e92dd2dbe. 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/US2S72384001.