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Coinbase’s Base delays B20 activation after second mainnet halt in two days

Coinbase’s Base delays B20 activation after second mainnet halt in two days

Base said June 25-26 outages lasted about 116 minutes and 20 minutes, traced to the same sequencer block-building bug, prompting another delay to B20 mainnet activation.

ETH

Fact Check
The official Base status page (status.base.org incident 5c4gm1wzbjs4) confirms Base Mainnet experienced two chain halts on June 25-26, 2026, both caused by a consensus problem producing invalid block sequencing at block 47806542, with a fix implemented June 26 at 16:11 UTC. This directly supports the claim of a 'second mainnet halt in two days' following a Thursday (June 25) ~2-hour outage caused by an invalid block and consensus bug, and a fix implemented ahead of the upgrade. Multiple independent outlets (crypto.news, cryptobriefing) corroborate. The only minor discrepancy is naming: the upgrade is officially 'Beryl,' which introduces the B20 token standard and B20 Activation Registry; the claim's 'B20 Registry launch' is a slight simplification but substantively consistent, as the upgrade was timed around B20 Activation Registry initialization. The substance of the claim is accurate.
Summary

Coinbase-incubated Ethereum layer-2 Base suffered two mainnet disruptions in two days and again delayed activation of its B20 token standard on mainnet. Base later said the June 25 and 26 outages lasted about 116 minutes and 20 minutes, respectively, and that both incidents were caused by the same sequencer block-building bug, with a restart race condition indirectly contributing to the second disruption. Base said funds remained safe and that a revised mainnet activation timeline for B20 would be announced, while Sepolia and Vibenet remained on schedule.

Terms & Concepts
  • sequencer: A system used by some layer-2 networks to order and build blocks before transactions are finalized on the underlying chain.
  • B20 token standard: A protocol-level token framework on Base designed to let tokens operate natively at the network level rather than only as smart contracts.
  • stale blocks: Outdated blocks that were incorrectly used in the sequencing process, contributing to the block-building fault Base identified.