Stablecoins have a transparency problem, and it’s not the kind regulators worry about. Every USDC or USDT transfer on a public blockchain broadcasts your balance, your counterparty, and your entire transaction history to anyone with an internet connection and a block explorer.
Miden, a zero-knowledge blockchain that spun out of Polygon in 2025, thinks it has a fix. The project announced USDCx on August 12, a new stablecoin backed 1:1 by USDC reserves and issued through Circle’s xReserve infrastructure. The core pitch: transactions are encrypted by default, with selective disclosure available only when regulators come knocking.
How USDCx actually works
At its foundation, USDCx relies on Miden’s zero-knowledge architecture. In practical terms, that means the network can verify that a transaction is valid, that balances add up, and that no coins were conjured from thin air, all without revealing who sent what to whom.
Balances, counterparties, and transaction histories remain encrypted unless a user or institution opts to disclose them. That opt-in disclosure mechanism is designed to satisfy specific regulatory requirements, including sanctions screening and the Financial Action Task Force’s Travel Rule, which mandates that certain identifying information travel alongside cross-border transfers above a threshold.
