Arbitrum is a decentralized layer-2 Ethereum scaling solution. Therefore, no one actually owns Arbitrum. However, if you are interested in learning about the company behind the project, all the credit goes to the New York-based Offchain Labs. As far as the founders are concerned, Ed Felten, Harry Kalodner, and Steven Goldfeder are the illustrious names behind Arbitrum. As for the token holding stat, 42.78% of the total ARB tokens are owned by the DAO treasury whereas the Offchain Labs (team and advisors included) own 26.94% of the total supply.