Base Activates Cobalt Upgrade on Mainnet

The Base L2 network team activated the Cobalt upgrade on its mainnet on September 30, 2026. The update introduces 'Validity Transactions,' which allow users to attach on-chain conditions to signed operations, ensuring they remain inactive until specific parameters—such as wallet balances or smart contract states—are met. Additionally, the upgrade enhances the B20 standard for tokenized assets, enabling issuers to apply complex, composite policies to tokens by combining allowlists and blocklists with logical operators.