thumb|right|Cover of Ulk, October 1920 with drawing by Paul Halke The German language satirical magazine Ulk was printed from 1872 until 1933 by the publisher Rudolf Mosse. Its headquarters was in Ber
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 0x01b7a1da66731604029c2d38704f3af0eaee46bbf7583c8c200e3cf82213a359. 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/00402ec8-31b6-4c21-9c72-fd9ddf12a818.json and https://artists.proofprofile.net/proofs/artist/00402ec8-31b6-4c21-9c72-fd9ddf12a818.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 0x866f0b4e223692e1fec08dd9178f528ded70481cb474b403267d067a01e0e388. 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/QZFZ41985276.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2e3b554b3d443c7d1bdfa66d4d37a61705c3652e5caa83ae30860eb058405612. Chain 2 (Bitcoin): anchored in block 956482 (2026-07-03T10:33:57Z), 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/QZFZ72042929.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xca113b28d355a68ecee18b378a540f2e9bcefbe8f51228abe363c88409d8e592. Chain 2 (Bitcoin): anchored in block 957752 (2026-07-12T20:53:32Z), 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/QZFZ72042930.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xda59d14c50d2cb4a1cadd69d78e294be8596bb41e90ccb8236aacc97622e4c13. 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/QZFZ72042932.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x52850e33b19330c79171aab8050bab43214200821715b44779a199211783d251. Chain 2 (Bitcoin): anchored in block 959100 (2026-07-22T05:29:55Z), 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/QZFZ72042933.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5504de6a6475303dce0ee5cca81ad1d7c778594e98a45f8b457cf88715d32b67. Chain 2 (Bitcoin): anchored in block 958943 (2026-07-21T00:27:37Z), 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/QZFZ72042934.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb865d25db5db95fa23318dfc8a61ef5712de1d0a16d1b553934eda698af47700. Chain 2 (Bitcoin): anchored in block 958461 (2026-07-17T23:18:11Z), 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/QZFZ72042935.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x25e02feebe045a2095128aa677f6a3ac79c274f3f994fca69d48d66df665997b. Chain 2 (Bitcoin): anchored in block 959043 (2026-07-21T18:40:26Z), 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/QZES52189990.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3d35e6609353d9201c013f14becffed3f26faa1f07be22e8b7f598f31cf6af46. Chain 2 (Bitcoin): anchored in block 958965 (2026-07-21T04:29:05Z), 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/QZES52189991.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc08bdfb0c1b38c27eec0d7f21905856dec094ee1bc3fcedfd3aec6754bf420ef. Chain 2 (Bitcoin): anchored in block 958166 (2026-07-15T15:55:19Z), 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/QZES52189992.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x67cfc0005c612fafc64c57130be0052eb34f949a5e2aa42935fec40b936f2a89. Chain 2 (Bitcoin): anchored in block 956856 (2026-07-06T01:25:57Z), 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/QZES52189993.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfc92cf603c95204a19cc7638872a19c5f9f45add1e453693f86717d826f10cd3. Chain 2 (Bitcoin): anchored in block 958611 (2026-07-18T21:24:44Z), 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/QZES52189994.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc734f10c82536be8f7c8c43f2f11cb39907afbc412e6378525d6b76b82714415. Chain 2 (Bitcoin): anchored in block 958918 (2026-07-20T17:58:04Z), 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/QZES82240741.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x72437a3b9e37f3321b5c94f49deaa35185bb5977c331e4dccb294478b5fe487d. Chain 2 (Bitcoin): anchored in block 958761 (2026-07-19T17:49:48Z), 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/QZES82240742.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7aab3c39e7655738c397e164791ddfe1072146bcbc042c365f29083de6608dd9. Chain 2 (Bitcoin): anchored in block 959043 (2026-07-21T18:40:26Z), 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/QZES82240744.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xff95ab886f818685977220c5455d5587ea2fbaa27b3e442cd13cd6dc46025a64. Chain 2 (Bitcoin): anchored in block 959001 (2026-07-21T11:41:42Z), 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/QZHN82494033.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbd393a1e2e9a9368481e1032ef38a035306a66757cfd72e7deea8bbb983e16d2. Chain 2 (Bitcoin): anchored in block 959084 (2026-07-22T00:50:00Z), 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/QZHN82494034.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb82c42970b726d2b8e2b4840edd34fd2d60ee96e673585aaa4fa9bb2b1c935e8. Chain 2 (Bitcoin): anchored in block 958263 (2026-07-16T08:19:47Z), 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/QZHN82494035.