Base Cobalt Upgrade Live: Conditional Trades, Token Seizure
Coinbase's Base network activated Cobalt on 30 September, adding conditional transactions and new B20 token controls. 200 ms blocks are still to come.
Base, the Ethereum layer-2 network built by Coinbase, switched on its Cobalt upgrade on mainnet on Wednesday, 30 September 2026, during a scheduled window in the evening UTC (late night in India). It is Base's third network upgrade this year. Cobalt adds "Validity Transactions", which wait on chain until conditions set by the user are met, and gives issuers of tokenised assets new controls, including the power to move a frozen holder's balance to another wallet.
Key takeaways
- Cobalt went live on the Base Sepolia test network on 23 September and on mainnet on 30 September 2026.
- Validity Transactions let a user sign a trade or withdrawal with conditions attached, such as a minimum balance or a block deadline. Base holds it until every condition is true.
- The B20 token standard, used for tokenised shares and other regulated assets, gains combined allowlist and blocklist rules, scheduled changes for stock splits, and a seizeWithMemo function.
- Seizure is opt in for each token and only the issuer can use it; Base itself cannot move anyone's funds.
- Faster 200 millisecond blocks and built-in smart accounts are planned for a later upgrade, not Cobalt.
What Validity Transactions do
Normally a transaction is either included in a block or rejected. With Cobalt, a user can send a normal signed transaction together with a list of conditions about the state of the chain: for example, "only execute if my wallet still holds at least this many tokens", "only if this contract value is above X" or "only before block N". Base keeps the transaction out of blocks until all the conditions match.
This matters for traders and apps. Until now, a conditional order such as a limit order or a stop loss on a decentralised exchange usually needed an outside "keeper" bot watching the chain and sending the trade at the right moment. Validity Transactions let the network do that job. Base also says the submissions stay private until they land, which can reduce front-running by bots. Two caveats: the conditions are not recorded on chain, and meeting them does not guarantee the transaction will be included.
New controls for tokenised assets
Base introduced its B20 token standard in June for assets that come with rules attached, such as tokenised stocks, funds and deposits. Cobalt adds three features:
- Composite policies. Issuers can combine two to four allowlists or blocklists with AND or OR logic. A tokenised fund could require that a buyer is both KYC approved and not on a sanctions list.
- Scheduled multiplier changes. Issuers can set the date for a change to the token's multiplier in advance, which is how corporate actions such as stock splits are handled.
- seizeWithMemo. This replaces the older burnBlocked function. Instead of destroying the tokens of a blocked holder, an authorised administrator can move the balance to another wallet, with a note recorded on chain. That is closer to how frozen funds are handled in banking, where money is moved under a court order rather than deleted.
Regulated issuers such as banks and fund managers want these controls before they put real assets on a public chain. It follows a wave of tokenisation moves this month; see our reports on tokenised stocks in the US and tokenised bank deposits.
What comes next for Base
Base has said it plans to cut block times from two seconds to 200 milliseconds, add native smart accounts with gas sponsorship and transaction batching, and bring in some of the improvements from Ethereum's Glamsterdam upgrade. The 200 ms work was briefly listed under Cobalt in early September but has moved to a later upgrade. No date has been set. Ethereum's own Glamsterdam timeline is in our Glamsterdam report.
Cobalt also moves Base's upgrade schedule into an Ethereum contract so future upgrades can activate without node operators restarting their software, though this is running in a monitoring-only mode for now.
What it means for Indian users
- No action needed for most people. If you hold ETH or USDC on Base in a self-custody wallet, the upgrade does not change your balance or address.
- Tokens can come with a freeze button. B20 assets are designed so an issuer can block or move balances. That is normal for regulated products, but it is very different from Bitcoin or ETH. Read the terms before buying any tokenised asset.
- Fees are paid in ETH. Fake "Base token" airdrop links are a common scam. Trust only announcements on official Base and Coinbase channels, and never connect your wallet to a site you reached from a direct message. Our airdrop tax guide explains how real airdrops are taxed in India.
- Using Coinbase from India? Our Coinbase India explainer covers what the Indian app offers.
To buy the coin that pays fees on Base, see how to buy Ethereum in India and the live ETH price: ₹256,969.
FAQ
When did the Base Cobalt upgrade go live?
On mainnet on 30 September 2026, a week after it went live on the Base Sepolia test network on 23 September.
What is a Validity Transaction on Base?
A normal signed transaction sent with a list of conditions about the chain, such as a balance or a block deadline. Base holds it until every condition is met, so apps do not need an outside bot to trigger it.
Can Base seize my crypto?
No. The seizeWithMemo function only works on B20 tokens whose issuer has turned it on, and only the issuer can use it. ETH and ordinary tokens on Base are not affected.
Does Base have 200 millisecond blocks now?
No. Base still has two-second blocks. The move to 200 milliseconds is planned for a later upgrade with no date announced.
This article is AI-assisted, educational and general in nature. It is not financial advice and never a guarantee of profit. Every trade is at your own risk on your own exchange. See our risk disclosure and editorial policy.
