Circle, the world’s second-largest stablecoin issuer, launched the public testnet for Arc, its open layer-1 blockchain network built to bring global financial infrastructure onchain.

The rollout, which Circle calls the “Economic Operating System for the internet,” includes participation from over 100 major companies spanning banking, capital markets and fintech — among them BlackRock, Goldman Sachs, Visa, Mastercard and State Street, according to a Tuesday announcement.

“With Arc’s public testnet, we’re seeing remarkable early momentum as leading companies, protocols, and projects begin to build and test,” Circle CEO Jeremy Allaire said. “Combined, these companies reach billions of users, move, exchange, and custody hundreds of trillions in assets and payments,” he added.

Arc is designed to provide predictable US dollar-based fees, sub-second finality and optional privacy controls, directly integrating with Circle’s USDC (USDC) stablecoin and payments stack. It aims to support a broad range of financial applications, from lending and capital markets to global payments and foreign exchange (FX).

Related: ClearBank to become one of first EU banks to join Circle Payments Network

Institutions join Circle’s Arc testnet

The testnet launch has drawn engagement from major institutions such as Apollo, BNY Mellon, Intercontinental Exchange and Deutsche Bank, as well as global payment firms Mastercard, FIS, Paysafe and Nuvei.

Major crypto platforms participate in Arc testnet. Source: Circle

Circle said Arc’s purpose-built architecture connects local markets across continents, from Africa to the Americas and Asia, offering enterprise-grade infrastructure for both traditional financial institutions and Web3-native projects.

Another important feature of Arc is its role in stablecoin infrastructure. The network supports fiat-pegged tokens, tokenized funds and FX liquidity. Issuers from seven countries, including JPYC (Japan), BRLA (Brazil), MXNB (Mexico) and PHPC (Philippines), have joined the testnet.

Arc’s ecosystem extends beyond finance, integrating with leading developer and infrastructure providers such as MetaMask, Fireblocks, Chainlink, Alchemy and LayerZero, alongside crosschain bridges like Wormhole and Stargate.

AI integration is also on the roadmap, with Anthropic’s Claude Agent SDK enhancing the developer experience through AI-powered tools.

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Circle to connect global markets

Allaire said Arc is “purpose-built to connect every local market to the global economy,” adding that it presents the opportunity for every type of company to “build on enterprise-grade network infrastructure.”

Circle said the long-term goal is to transition Arc into a community-governed network, expanding validator participation and establishing transparent governance.

Circle announced plans to launch Arc in August. At the time, the company said the network was set to use USDC as its native gas token. Last week, Allaire also announced that Circle is building private stablecoins on Arc.

Circle CEO announces building private stablecoins on Arc. Source: Jeremy Allaire

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