Circle Internet Group launched Arc’s public mainnet on September 16, bringing online a Layer 1 blockchain designed for payments, capital markets and other institutional financial applications. Arc uses USDC for transaction fees and currently operates with a permissioned validator model, while Circle’s roadmap contemplates a future transition from Proof of Authority toward Proof of Stake. More than 100 applications and more than 100 institutional and ecosystem builders were involved at launch.
According to Circle’s official announcement, the founding validator cohort includes BlackRock, The Depository Trust & Clearing Corporation, Galaxy, ICE, Mastercard, MoneyGram, SBI Group, Standard Chartered, Sumitomo Corporation, Visa and Worldpay, now part of Global Payments, alongside Circle. Validator participation is being introduced through a phased rollout rather than an unrestricted validator set, giving established financial and payment institutions a direct operational role in securing the network.
Arc combines that structure with deterministic sub-second finality and EVM compatibility. Existing Solidity contracts and Ethereum development tools can therefore operate on the network, while transaction fees remain denominated in USDC rather than a separate volatile gas asset. The design targets predictable settlement costs and rapid execution for financial-market workflows.
Credit and Trading Protocols Go Live on Arc
DeFi credit infrastructure was active from mainnet launch. In its Arc launch announcement, Morpho said it was live as a credit layer, while its official documentation confirms Morpho Blue supports variable-rate lending and borrowing on Arc. Morpho’s deployment provides lending infrastructure from day one, although protocol availability does not itself establish sustained borrowing demand or liquidity.
Morpho is live on @arc
Morpho powers earn & borrow use cases built on Arc as its credit infrastructure. pic.twitter.com/MqfCTkuuiL
— Morpho 🦋 (@Morpho) September 16, 2026
Aave also confirmed its deployment in an official Arc update. Aave V4 was activated with USDC, EURC, WETH and cirBTC as its initial reserves after its temporary deployment halt was lifted. Aave and Morpho therefore give Arc two distinct on-chain credit venues at mainnet launch, while actual usage will depend on deposits, borrowing activity and market depth.
Arc is purpose-built to support real-world financial flows at scale. The deployment launches with a Core Hub and two markets.
The main market supports @USDC, EURC, WETH, and cirBTC, while a the forex market pairs USDC and EURC for stablecoin borrowing.https://t.co/AKdNxQxuPO
— Aave (@aave) September 16, 2026
Trading infrastructure includes Uniswap, Aero and fomo, while tokenized financial products form another major component of Arc’s market design. Circle’s launch materials include USYC and BUIDL among assets intended for trading, lending and collateral use. BlackRock’s BUIDL should still be treated as an announced Arc deployment rather than assumed to be fully operational solely from the mainnet launch, because Circle’s earlier integration announcement described BlackRock as expected to deploy the fund using Arc’s native USDC infrastructure.
Institutional Integrations Extend Beyond Launch
Arc’s institutional roadmap extends beyond applications already active on the network. Circle and DTCC are working toward enabling tokenization of DTC-custodied assets on Arc beginning in the second half of 2027. BNY and Standard Chartered have also been identified as institutions exploring integrations involving custody, stablecoin access, foreign exchange and repo infrastructure. Those initiatives remain future or exploratory integrations rather than completed production capabilities.
The network’s pre-launch transaction figures also require context. Circle said Arc’s testnet processed more than 700 million transactions in under a year, while its private-mainnet phase involved more than 100 ecosystem and institutional builders. The 700 million figure measures testnet activity, not production transaction demand on the newly launched mainnet, so it should not be used as evidence of current institutional adoption.
The next meaningful indicators will come from production usage, including liquidity and borrowing in Aave and Morpho, trading volumes, stablecoin settlement activity and the execution of announced institutional integrations. Arc has now crossed from testing into public mainnet infrastructure, but durable financial activity will determine whether its institutional positioning translates into measurable adoption.
