Extended, the perpetual futures exchange that holds most of the money on Starknet, moves its settlement network to Arc, the layer 1 blockchain built by Circle, on Thursday 22 October at 13:00 UTC (15:00 in Paris). Users who hold more than $1 of USDT or wBTC in any sub-account face an earlier cut-off: today, Wednesday 21 October, at midday UTC. Extended’s migration page, published on 8 October, calls the move “the first step of a strategic partnership” with Circle, the issuer of USDC.
The exact hour is not the same everywhere. Extended’s documentation gives 13:00 UTC on Wednesday 21 October (15:00 in Paris and Rome). The notice Extended posted on X on Tuesday 20 October gives 12:00 UTC on Wednesday 21 October, according to The Defiant’s report as republished by cryptonews.net; we could not open the X post ourselves. Until Extended settles the point, the safe reading is the earlier one: act before 12:00 UTC on Wednesday 21 October, which is 14:00 in Paris and 8:00 in New York.
For everyone else, nothing has to be done. Accounts, positions and balances carry over, and trading is meant to continue during the switch. The bigger consequence is for Starknet itself: on DefiLlama’s count, Extended accounts for roughly three quarters of the staking or liquidity, measured at current market prices. It is the main size metric in DeFi.">value locked on the network.
Extended Starknet Arc migration: Wednesday’s deadline is 12:00 or 13:00 UTC
The Defiant summed up the problem in its headline story: the exchange’s notices “give conflicting deadlines”. Extended’s own page, the most detailed source and the one we reopened this morning, sets the action deadline at 13:00 UTC on Wednesday 21 October, or 9 a.m. in New York. The X notice of Tuesday 20 October, as The Defiant reported it, says 12:00 UTC on Wednesday 21 October, or 8 a.m. in New York. A graphic attached to that post showed a third date, Monday 19 October at 8 a.m. ET, which has already passed and matches neither text.
One hour does not sound like much. It matters here because the penalty for missing the cut-off is automatic: the exchange freezes the account and then closes positions in the affected sub-accounts at mark price. Anyone who still holds USDT or wBTC on Extended this morning should treat 12:00 UTC on Wednesday 21 October (14:00 in Paris) as the deadline and not wait to see which notice was right.
The rule only bites above a threshold. It applies if USDT or wBTC is worth more than $1 in at least one sub-account. Smaller balances are converted automatically, without a fee and without a premium.
USDT and wBTC holders: convert in the app or withdraw
Neither USDT nor wBTC will exist on Arc, so Extended stopped accepting deposits of both on every chain on Thursday 8 October, the day it published its migration page. Holders above the $1 line get two choices.
- Authorise the conversion in the Extended app. USDT becomes USDC and wBTC becomes cirBTC, the bitcoin-backed token issued by Circle, at 1:1 and with no fee. Extended adds a 0.50% premium on the converted amount, credited within eight hours after the migration, which starts on Thursday 22 October at 13:00 UTC.
- Withdraw USDT and wBTC until each asset is worth $1 or less in every sub-account.
The authorisation has a few conditions worth reading twice. It cannot be revoked once given. It covers both assets and all sub-accounts in one go. It can only be given in the app, not through the API, which matters for traders who run bots. Withdrawals stay possible after authorising, until Thursday 22 October at 13:00 UTC (15:00 in Paris), and only what remains on the account is converted.
On a $10,000 USDT balance, the premium comes to $50. On a balance worth 0.5 wBTC, it is 0.0025 BTC worth of cirBTC.
Do nothing, and positions are closed at mark price
Extended spells out what happens to accounts that still hold more than $1 of USDT or wBTC when the deadline passes on Wednesday 21 October. The sequence runs in four steps.
- For up to 30 minutes after Wednesday’s deadline, every sub-account of the user is frozen: no trading, no orders, no deposits, withdrawals or transfers.
- In each sub-account that holds the assets, Extended cancels all orders, including stop-loss, take-profit and API orders, and closes open positions at mark price, without fees.
- The USDT and wBTC are sent to the login wallet, with the withdrawal fees paid by Extended. EVM wallets receive them on Ethereum plus $5 of ETH for gas; Starknet wallets receive them on Starknet, without the ETH.
- The account then migrates to Arc with all the others from Thursday 22 October at 13:00 UTC.
The freeze is the part that can hurt people who did nothing wrong in their other sub-accounts. Sub-accounts without USDT or wBTC are not closed, but they are frozen too during those 30 minutes, and normal liquidation keeps running. The owner cannot add margin or close a position while the market moves. Extended’s advice is to make sure those sub-accounts are well margined before the deadline.
If the transfer back to the wallet fails, for a legal or compliance reason, a blocked address or a network failure, the assets stay attached to the account and go through a recovery process. Extended does not say how long that takes.
Everyone else: no action, but a two-hour pause on Thursday 22 October
Most users do not hold USDT or wBTC on Extended, and for them the migration is meant to be invisible. Balances, positions, orders, trading history, points, referral status and fee tier all carry over. Login keys stay the same, Starknet wallets included, so a user who signs in with a Starknet wallet today can keep doing so on Arc.
The collateral moves in different ways. USDC is burned on Starknet and minted as native USDC on Arc through CCTP, Circle’s cross-chain transfer protocol, for the same amount and the same account. ETH moves 1:1 as wETH. The XVS vault token keeps its assets and its withdrawal rights.
One practical point for Thursday 22 October: deposits and withdrawals pause for up to two hours during the migration, which starts at 13:00 UTC (15:00 in Paris), while trading and transfers between sub-accounts continue. Positions can still be liquidated during that window, and fresh collateral cannot come in from outside. Extended asks users to keep enough margin on their sub-accounts to ride it out.
The timeline in one table
| Date and time (UTC) | What happens | Source |
|---|---|---|
| Thursday 8 October | USDT and wBTC deposits disabled on all chains | Extended docs |
| Monday 19 October, 12:00 (8 a.m. ET) | Date on a graphic attached to the X notice, as reported; now passed | The Defiant via cryptonews.net |
| Wednesday 21 October, 12:00 (14:00 Paris) | Action deadline in the X notice of Tuesday 20 October, as reported | The Defiant via cryptonews.net |
| Wednesday 21 October, 13:00 (15:00 Paris) | Action deadline in Extended’s documentation | Extended docs |
| Wednesday 21 October, up to 30 minutes after the deadline | Freeze, then forced closures in sub-accounts still holding USDT or wBTC above $1 | Extended docs |
| Thursday 22 October, 13:00 (15:00 Paris) | Settlement moves to Arc; last moment to withdraw USDT and wBTC; deposits and withdrawals paused up to 2 hours | Extended docs |
| Thursday 22 October, within 8 hours after the migration | 0.50% conversion premium credited | Extended docs |
Why Arc: a new Circle chain and a partnership with no published terms
Arc is young. Circle opened its public mainnet on 16 September 2026, The Block reported, after a private phase with more than 100 builders. Fees on the chain are paid in stablecoins, starting with USDC, and Circle promises sub-second finality, according to its August announcement.
The validator set is the main difference with Starknet. Arc runs with permissioned validators, known institutions chosen by Circle; the 11 founding names announced in August include BlackRock, DTCC, ICE, Mastercard and Visa, joining in phases. Starknet, by contrast, is a rollup on Ethereum that is still decentralising. Circle also minted 10 billion ARC tokens at launch, which The Block described as a technical milestone, with no decision on a public token.
Circle’s chief executive, Jeremy Allaire, framed the launch this way: “USDC was step one. Arc is the network built for what comes next.”
For a perp exchange whose collateral is mostly USDC, the logic is easy to follow: settlement on the chain of the stablecoin issuer, native USDC, gas paid in USDC. What the “strategic partnership” includes is less clear. Extended has published no financial terms, and we found no statement from Circle on the deal and nothing showing that Circle invested in Extended. Our page on Circle, USDC and Arc covers how the issuer makes money and why it built its own chain.
Arc already holds more than Starknet. DefiLlama put Arc’s TVL at $531.9 million on 21 October, led by Morpho Blue at about $302 million and Aave V4 at about $182 million. If Extended’s $117 million arrived in full, it would add roughly a fifth to that total, our own arithmetic. It may not all arrive: some holders are withdrawing their USDT and wBTC rather than converting.
Starknet loses the app that holds about three quarters of its TVL
The figures come from DefiLlama’s public API, pulled around 06:10 UTC on 21 October. Extended held $117.25 million, almost all on Starknet ($0.15 million sits on Ethereum). Starknet as a chain showed $157.96 million. On that measure, Extended alone accounts for about 74% of Starknet’s total value locked.
That share deserves a caveat. DefiLlama’s protocol list for Starknet includes entries such as Starknet BTC staking and exchange wallets of Binance and Bybit, and those entries add up to more than the chain figure, so some are left out of the chain total. The ratio depends on what is counted. “Roughly three quarters, per DefiLlama’s chain page” is as precise as it gets.
| Measure (DefiLlama, 21 October) | Value |
|---|---|
| Extended TVL, all chains | $117.25M |
| Extended TVL on Starknet, 15 October | $120.2M |
| Extended peak TVL on Starknet (4 February 2026) | $217.7M |
| Starknet chain TVL | $157.96M |
| Extended share of Starknet TVL (our calculation) | about 74% |
| Extended Perps open interest, 24h | $94.7M (+2.7% in a day, -6.2% in 7 days) |
| Arc chain TVL | $531.9M |
There has been no rush for the exit so far. Extended’s daily TVL on Starknet slid from $120.2 million on 15 October to $117.25 million this morning, a drift of about 2.5% in six days. It is down 46% from its February peak of $217.7 million. Funds have little reason to move early: they leave Starknet in one go on 22 October, when settlement switches.
Open interest tells a similar story. DefiLlama showed $94.7 million of open positions on Extended Perps over the last 24 hours, 6.2% less than a week earlier and 5.2% less than a month earlier. Traders are not closing en masse ahead of the switch.
What does it leave on Starknet? Lending markets such as Vesu, the Ekubo exchange, Endur’s proof of stake coin with a protocol that stakes it for you and issues a transferable token (such as Lido stETH or rETH) representing the deposit plus rewards, which you can use or sell while the coins stay staked.">liquid staking and the BTC staking programme, all far smaller than Extended. Our Starknet project page describes the rollup, the STRK token and its risks.
STRK: no visible reaction to the departure
STRK traded near $0.0561 at 06:11 UTC on Wednesday 21 October in Coindaro’s market data, 0.1% lower over 24 hours and 34.5% lower over seven days. Bitcoin lost 1.3% over the same week, in the 06:04 UTC snapshot.
That weekly fall is hard to pin on Extended. The exchange announced the move on 8 October, at the start of a run that took STRK up about 122% in three days, according to the Indonesian aggregator Pluang; the token then gave much of it back around the 15 October monthly unlock. The departure was public all along, and the price swung for other reasons. We found no statement from StarkWare or the Starknet Foundation on Extended leaving, and no price analysis tied to it.
Starknet is already debating its own exit from Ethereum
The timing is awkward for Starknet. Last week, a governance poll on post-quantum security drew 99.95% support for researching a move away from Ethereum to a layer 1 of its own, with votes delegated to the Foundation making up about 94% of the total, as we reported in our story on the Starknet quantum resistance poll.
The two stories are not linked: Extended gave no reason beyond the Circle partnership, and nothing in its documentation mentions Starknet’s governance. But they point the same way. The network’s largest application is leaving for a chain run by a stablecoin issuer, while the network weighs whether to stop settling on Ethereum.
What a settlement network means for a perp exchange
Extended is a decentralised exchange for perpetual futures, contracts that track an asset’s price with no expiry date and are often traded with leverage. Its team came from Revolut, and DefiLlama describes it as a venue with cross-asset collateral, unified margin, perps, spot and lending markets.
For an exchange like Extended, the settlement network is the blockchain where collateral, balances and positions are recorded. That chain holds the money and enforces who owns what. Moving settlement from Starknet to Arc does not change the trading screen; it changes where users’ money sits and which validators secure it. Our guide to DeFi, lending and DEXs explains the basics.
European users: check the margin, keep records
Extended says its service has eligibility and jurisdiction restrictions. We did not check whether it appears on the AMF, Consob or ESMA registers of authorised crypto-asset service providers, and nothing in its documentation suggests it is a licensed European firm.
Extended itself warns that closing positions or converting assets “may have tax consequences”. A forced closure is a disposal like any other, and a USDT to USDC swap is still a swap. How each is treated depends on the country, so users in France or Italy should keep the conversion record and the closing prices and check with the tax authority or an adviser.
There is a regulatory twist for euro-area holders. After the conversion, Extended’s collateral will be almost entirely USDC, an e-money token under MiCA. From 12 November, the European Banking Authority takes over supervision of USDC’s reserves, as explained in our piece on the EBA and USDC.
What is still unknown before Thursday
Extended has not said publicly which of the two times, 12:00 or 13:00 UTC, prevails. Its documentation asks users to contact support on Discord before trading if anything looks incorrect.
Nobody knows yet how much of the $117 million will reach Arc. Users who withdraw rather than convert take their USDT and wBTC elsewhere, and the 22 October figures on DefiLlama will give the first answer.
The partnership terms remain unpublished, and so does any reaction from StarkWare. The migration itself starts on Thursday 22 October at 13:00 UTC (15:00 in Paris), with deposits and withdrawals back within two hours if the schedule holds and the 0.50% premium due within eight hours after that.