Current outcome
Base completed its third mainnet upgrade, Cobalt, which includes condition-gated Validity Transactions, three new B20 token-standard features, and an opt-in administrative balance-seizure rule (seizeWithMemo) for B20 tokens.
Progress timeline
2 material updates- #01
【Base 完成 Cobalt 升级，新增条件交易并扩展了 B20 资产功能】
Base completed its third mainnet upgrade, Cobalt, adding condition-gated Validity Transactions and three new B20 token-standard features, with a roadmap toward 200ms block times, native smart accounts, and gas sponsorship.
Source evidence: foresightnews
- #02
Base’s Cobalt upgrade adds another rule to affect token balances
The Cobalt upgrade introduces an opt-in administrative balance-seizure rule (seizeWithMemo) for B20 tokens, requiring issuer eligibility configuration, SEIZE_ROLE authorization, and a separate recipient policy, while preserving token supply and keeping burnBlocked deprecated but callable.
State after update: Base completed its third mainnet upgrade, Cobalt, which includes condition-gated Validity Transactions, three new B20 token-standard features, and an opt-in administrative balance-seizure rule (seizeWithMemo) for B20 tokens.
Source evidence: CryptoSlate