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 → 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 0x3d214eb9a2e3e3d3a6412646dd8f839dbf7e25f5453ce132389658acf29d5b0f. Chain 2 (Bitcoin): anchored in block 953803 (2026-06-15T15:41:00Z). Bridge: the canonical record inside this Bitcoin proof contains the same CopyrightID. Verify: download https://artists.proofprofile.net/proofs/artist/e5d93705-39d6-4b57-8d0f-10da936da835.json and https://artists.proofprofile.net/proofs/artist/e5d93705-39d6-4b57-8d0f-10da936da835.ots, run `ots verify -f record.json proof.ots` (https://opentimestamps.org).
She's Into Me: Songs By Chad Wagner and Chuck Hays
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 0x77a793034df0421d9ad5a45b8bd07fdee79175f237903c57ccc2b757f2b0429c. 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/TCADN1898681.