thumb|John Leech, Substance and Shadow (1843), published as Cartoon, No. 1 in Punch, the first use of the word cartoon to refer to a satirical drawing A cartoon is a type of visual art that is typica
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 0x67b938671ba750b38187de8ee686efb9782ebfdfb9c37c919feb23c6c592e40e. Chain 2 (Bitcoin): anchored in block 953706 (2026-06-14T23:14:49Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/7c28efc9-496c-415b-86d7-24b66cb28a8b.json and https://artists.proofprofile.net/proofs/artist/7c28efc9-496c-415b-86d7-24b66cb28a8b.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 0x2e9780f33665f5e1deaf3971f63113d6c40e8c2e97f15a24a6c4e9a4a7d5d5d4. 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/TCAEY2007607.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3a241fc970c621efbf23a2caf6c38332db91dc4e1f98279f7fc0f565d1da27cb. Chain 2 (Bitcoin): anchored in block 959023 (2026-07-21T15:22:58Z), 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/TCAFD2087113.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf1a6cb22be6d7b6dd31fc7ccdb6adac8bb52b2317ed02e5e926d507d6e3190f. 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/QZNMV2080540.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x3f6e3e839a791c0ac022d98339e5d377ac00c7187bb309398474e3519b3f0127. 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/QZNMW2177469.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf79b5025e9fc1f960063a60ce1271198c4dea3c64326ecfbc3d2326a4ee022d5. Chain 2 (Bitcoin): anchored in block 957073 (2026-07-07T18:39:05Z), 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/TCAFS2160436.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xa47a77458f0d9a4a32241ce52a3b5c3cb05c5d3a18fe300426788360f45b640c. 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/QZNMX2140140.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf477e7f90623bf28b01d3814a5b8bc213cde54d0ad380ad991c438d07daefc43. Chain 2 (Bitcoin): anchored in block 960422 (2026-07-31T15:27:29Z), 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/QZL382246166.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x145191f700d1e9f3b840a6cbbaa3fa97cf00582aa7ff36c72fc37abb08ec98a3. Chain 2 (Bitcoin): anchored in block 956745 (2026-07-05T05:33:35Z), 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/QZFZ72265167.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5e4c72017fb45984f0ca161421c1aff18717bffdf45c86ca729d00776ba8ce09. Chain 2 (Bitcoin): anchored in block 960236 (2026-07-30T09:37:10Z), 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/QZFZ72261507.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x0569832bb5a8f7e3ff1df7ee5d45266dd6b1a00672c108b62417b57fa6c1188e. Chain 2 (Bitcoin): anchored in block 960344 (2026-07-31T04:14:58Z), 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/QZFZ72261508.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x9364e5d188ad416e6fb9545ea793c0732bc603211098a5342fa704385637175e. 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/QZFZ72261509.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xabbeb351f2c20a66dc6107f24f317e78eea151f1b7657abbf55f9a911aea556a. 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/QZFZ72261511.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe8a5b493d7d2df70eeaea79a8b9f921767774704a00c9a3a1d3b379210de12a1. 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/QZFZ72261513.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6eaac4555e24e7d3d1b76ff69a623e5c4c7b9d26efa7ba85e37cfb23b2554682. Chain 2 (Bitcoin): anchored in block 960397 (2026-07-31T12:24:41Z), 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/QZFZ72261516.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x5141f5563863d407f93c49137c181b25b7c09d66b132b7f2eabe9e73acb2f59a. Chain 2 (Bitcoin): anchored in block 960503 (2026-08-01T03:41:24Z), 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/QZFZ72261517.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x8c044bb3c0a4c2774480e2fa64b6c7e299f12c2597735bb11aee15dc27672e4b. Chain 2 (Bitcoin): anchored in block 960468 (2026-07-31T21:25:57Z), 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/QZFZ72261518.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4d79ec181a71a81e335f9d86b9c868967e8481b6085faa90a1040c42f653c002. Chain 2 (Bitcoin): anchored in block 960478 (2026-07-31T23:30:38Z), 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/QZFZ72261519.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x691b1b0cabe46c8d4736b04df77860968bd99601458c7e9400d70d441e80ca55. Chain 2 (Bitcoin): anchored in block 960284 (2026-07-30T17:23:26Z), 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/QZTBB2214961.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xb97f291b46ac325ec1d4585a976593c77f48db41aa71122cb7d108f9c92ddd49. Chain 2 (Bitcoin): anchored in block 959087 (2026-07-22T02:05:55Z), 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/QZK6M2329678.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xfeef86a1b32c4a667508b92debeb243ed1b031164347734a0ceab208579ce8bd. Chain 2 (Bitcoin): anchored in block 960175 (2026-07-30T00:16:15Z), 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/QZNWV2365922.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x560289f5b5381e5d628d82b8c27fa6f62fe7989b542282524f2eda96396a4dbc. 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/QZTB42357048.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x77abc65e25dce6e91ca07a437e8e24cbd559fb331e47b6f7ccbf9daee5606095. 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/QZNWQ2131130.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x956edefe460c1ce4d40109b7190a985941bd602797b178f59947dafc979154b3. 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/QZNWQ2131132.