C2 or a derivative (C-2, C2, etc.) may refer to: Mathematics and physics C2, one of the common notations for the cyclic group of order 2 C2 differentiability class C2 or , the complex coordinate p
1. Compute SHA-256 of OTSCanonicalRecord value → must equal OTSHash 2. Open OTSProofURL → extract Bitcoin block number → must equal OTSBitcoinBlock 3. GET OTSBitcoinBlockVerifyURL → block must exist at that height 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 artist was registered on CopyrightChains at OTSTimestamp, independently verifiable on Bitcoin
Dual-chain trust anchor. Chain 1 (CopyrightChains): CopyrightID 0xf37bffb76524c0dd3b35abe6c24e5ff6c963a42d67216850738e1f457123fbf3. Chain 2 (Bitcoin): anchored in block 953408 (2026-06-12T19:28:13Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e3d4536f-4fb6-4b5c-990f-12fee11b7a57.json and https://artists.proofprofile.net/proofs/artist/e3d4536f-4fb6-4b5c-990f-12fee11b7a57.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).