Avtar Singh Sandhu (9 September 1950 – 23 March 1988), who wrote under the pen name Pash, was an Indian poet, one of the major poets in Punjabi of the 1970s. He was killed by Sikh extremists on 23 Mar
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 0xa575be56e0b3250e56437f06408486c4a071590c6e06966996fdb73016e9d512. 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/1ad45146-bab4-4fa1-a03b-bf2e3f7aecb9.json and https://artists.proofprofile.net/proofs/artist/1ad45146-bab4-4fa1-a03b-bf2e3f7aecb9.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 0xdfb0867ef522e4c15e1c3e2e62217a2f13269c1012cc26f0000a5bc116c4f36c. 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/QZFZ62440757.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x018811d1ec8c82b4a9c96f67523416dab75336bf91583972b1a804414dceeccb. 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/QZQAY2344060.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x6407c8af305989f1239eb91ab5e95a3fed0abae89c7ac00d602bc10afd9b82d9. 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/USA2P2251911.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcd92a2ea55375d0702c3ae49c038662038cf91c8889f0bd4566fed7af338d5c2. 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/BK4DA2321351.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc737b10771bc4dd98df411a77ca47eaed92f70c24980cd9b8e4bee6e5855f5a2. 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/USA2P2250264.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf4767fb60021ff07c266b1e59639073ed79ae6a42085d37241fc92b6e794ae40. 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/GX53U2341955.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xcb793b96afe548c71b00c7030cc026584b1380273baa3503fb698686823c2229. 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/USA2P2232201.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x7ea63d77b900153287728e9a0335961d0ebf3b26b6b886b97ac04ab96031bb9e. 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/USA2P2233782.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xab5fb032988c543af656f1f1bd3d4438a1a36686d09579bf1c370ab581094ecd. Chain 2 (Bitcoin): anchored in block 959159 (2026-07-22T19:46:35Z), 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/USA2P2233780.
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 0xe4e02fa40f38e99a739686875874b8d3bae4a91392f924353e262464a9c68855. 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/USA2P2233559.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xbf97ac6f078078a22da69064654a102df56013871286564badf54711ae6f2c8d. Chain 2 (Bitcoin): anchored in block 960294 (2026-07-30T18:46:00Z), 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/QZS7J2331504.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf571269f67ccc85f595dd3edc726352848d91781387b4e1d22fb6a56407e8f6e. Chain 2 (Bitcoin): anchored in block 960181 (2026-07-30T00:53:20Z), 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/USHM92069214.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x4f0a66b7a6975d97512472b34115ed8cf21aa48d9d4e45bb31c1e26616758ac7. Chain 2 (Bitcoin): anchored in block 960473 (2026-07-31T22:27:44Z), 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/QZQAY2388887.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xe1ce25ba5f43d4b98018120afcb050b03138a289ed4f4a38bf270f0bce99b1c3. Chain 2 (Bitcoin): anchored in block 960418 (2026-07-31T15:20:15Z), 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/QZSYP2373532.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x2fbcbb809f9177abb2ece190d640c626caa2a75d5972c65432bdbb070ef82943. 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/USA2P2242793.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xc3aadacdbab7cceea327bca9a4d90ef02b19d69c49f03b4f01f65beec889e98f. Chain 2 (Bitcoin): anchored in block 960296 (2026-07-30T19:11:09Z), 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/USDY42297952.