Circle will launch its Arc blockchain on a public mainnet on 16 September, with BlackRock, Visa, Mastercard, Standard Chartered and other major financial institutions joining as founding validators.
Arc is currently operating on a private mainnet involving more than 100 institutional and ecosystem participants, according to Circle. The public launch will move the project beyond its earlier public testnet phase and open the network to a wider range of blockchain applications and financial services.
BlackRock, The Depository Trust & Clearing Corporation (DTCC), Galaxy, Global Payments, ICE, Mastercard, MoneyGram, SBI Group, Standard Chartered, Sumitomo Corporation and Visa will join Circle in securing and governing the network from launch.
Circle said the validator group had been designed around institutions that are also developing products and services on Arc, rather than relying solely on independent operators. It said that approach was intended to satisfy the operational, compliance and security standards expected of financial market infrastructure while retaining support for open blockchain applications.
The announcement marks the latest stage in Circle’s effort to build a blockchain aimed specifically at institutional finance. More than 100 banks, asset managers, blockchain companies and other organisations had previously been testing the network before it entered its private mainnet phase.
Mastercard Chief Product Officer Jorn Lambert said the future of payments would involve different payment rails and forms of value working together, rather than being controlled by a single network. He said Mastercard’s position as a founding validator was consistent with its efforts to link blockchain-based payment systems to established financial infrastructure.
MoneyGram Chairman and CEO Anthony Soohoo said the company had joined Arc because it believed compliant blockchain infrastructure would be needed for stablecoins to support real-world movement of money.
Standard Chartered Global Head of Transaction Services and Digital Assets Ole Matthiessen said wider institutional use of digital assets depended on infrastructure that met regulatory and operational requirements. He added that the bank regarded Arc as a foundation for secure financial applications operating onchain.
Visa Global Head of Growth Product and Partnerships Rubail Birwadker said trusted blockchain infrastructure would help onchain payments expand, confirming that Visa would participate as a network validator.
BlackRock and DTCC integrations
Circle also outlined a series of institutional integrations planned for Arc’s public mainnet launch.
BlackRock intends to deploy its BlackRock USD Institutional Digital Liquidity Fund (BUIDL) on Arc using the blockchain’s native USDC integration. Circle said the arrangement would allow institutional investors to subscribe to, redeem and deploy fund assets within one onchain environment.
Robert Mitchnick, BlackRock’s Global Head of Digital Assets, said the move reflected the growing importance of stablecoins in financial markets.
“Stablecoins and tokenized assets are inextricably linked within the future of financial market infrastructure. Purpose-built rails like Arc can support faster settlement, improved collateral mobility, and broader institutional adoption of digital assets.”
Circle is also working with DTCC on a plan to tokenise assets held at The Depository Trust Company (DTC) on Arc from the second half of 2027.
The proposed integration would allow market participants to use third-party applications on Arc for stablecoin-based settlement outside DTC while still referencing assets tokenised by DTC. Circle said those assets would continue to give investors the same rights and protections as traditionally held securities.
The company said the project supported DTCC’s multi-chain strategy, which aims to accelerate settlement, extend trading hours, improve the movement of assets and reduce operational costs through distributed ledger technology.
DeFi, payments and wallet support
Circle said a number of decentralised finance protocols, payment companies, exchanges and wallet providers were preparing to support Arc when the public mainnet goes live.
Aave, Aerodrome, FalconX, Galaxy, GSR, Keyrock, Morpho, Nonco, Uniswap and XFX are expected to provide borrowing, trading and liquidity services on the network.
Payment providers Rain, Thunes and Wirex are preparing to route stablecoin payment and settlement activity through Arc. Circle also identified Binance Wallet, Chainlink, Fireblocks, Kraken, Ledger, MetaMask, Uniswap Labs and Upbit as wallet and infrastructure providers expected to support access to USDC, custody services and transfers of assets between blockchains.
Circle co-founder, chairman and chief executive Jeremy Allaire said the combination of institutional validators and more than 100 enterprise and ecosystem builders already using Arc’s private mainnet placed the network in a strong position ahead of its 16 September public launch.
The company’s plan has developed through several announcements this year. In May, Circle launched the Arc blockchain initiative alongside a $222m ARC token presale, which valued the network at $3bn on a fully diluted basis.
At that stage, Circle described Arc as a public blockchain built for institutional finance, with USDC serving as its native gas token. It also highlighted sub-second finality, compatibility with the Ethereum Virtual Machine (EVM) and opt-in privacy.
Circle later introduced Arc Privacy, a confidential smart contract engine designed to allow businesses to keep selected transaction information and contract activity private while retaining access for compliance reviews and audits. The company said the technology was intended for uses including treasury management, payroll, lending, tokenised assets and consumer payments.
In April, Circle published a multi-stage quantum-resilience roadmap for Arc. It said quantum-resistant wallets and signature schemes would be available when the network launched, with further protections for validators, infrastructure and off-chain systems planned for later stages.
Circle said additional products would be introduced alongside the 16 September public mainnet launch. They will include a composable application framework for common onchain workflows, artificial intelligence-assisted developer tools, services for issuing and managing tokenised real-world assets, and interfaces for developers, users and autonomous software agents operating on Arc.
