XXL may refer to: XXL (club), in London, UK XXL (magazine), an American hip-hop magazine Penny Market XXL, a Romanian hypermarket chain XXL Sport & Villmark, a Norwegian sporting goods retailer F
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 0xd169bf1bccdf8e867ad17b77c9cbaa5cf9fff923943b3d2f48ac9ccfeb9edece. Chain 2 (Bitcoin): anchored in block 954638 (2026-06-21T03:45:44Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/d4eb259b-8d06-4b6a-95a0-e5099f2c0387.json and https://artists.proofprofile.net/proofs/artist/d4eb259b-8d06-4b6a-95a0-e5099f2c0387.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 0x67a141429570416494b3c44ad4e62f331a0b9a2ec91f0c9c9d6cdbd818a87908. Chain 2 (Bitcoin): anchored in block 959107 (2026-07-22T07:19:23Z), 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/ES5150377002.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x65efc13ac5e5c7c04110ba3f7ebd2b0aa852606a4210404f112592438732e001. Chain 2 (Bitcoin): anchored in block 958775 (2026-07-19T20:13:58Z), 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/ES5150377003.
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0x86cc5d6695ca79902c35a327eb9d387455489f9186502c333b5faa0266f21319. 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/ES5150577006.