Arc operates under proof-of-authority rules at launch with a permissioned validator set, with plans to explore a transition to a permissioned proof-of-stake model in 2027.

From the articleCircle Arc Mainnet Opens Wednesday: BlackRock, DTCC, and Visa Run Its NodesAlso in Circle launches Arc mainnet with BlackRock and Visa among validators, mints 10 billion ARC tokens, Circle Launches Arc Mainnet With BlackRock, DTCC and Visa as Validators - Decrypt, Circle Switches On Arc Blockchain and Mints 10 Billion Tokens It Has Not Promised to Sell - Unchained