The native system adds private ERC-20 balances, transfers and swaps on Starknet’s Ethereum Layer-2 ZK rollup without requiring a separate privacy coin or siloed liquidity.
Starknet launched STRK20 on June 9, 2026, adding a native privacy framework to its Ethereum Layer-2 ZK rollup (transaction-bundling network secured by zero-knowledge proofs). The system allows users to shield any ERC-20 token balance, make private transfers and execute private swaps without introducing a separate privacy coin or splitting liquidity into isolated pools. STRK20 uses a note-based privacy pool in which assets are turned into encrypted notes, while zero-knowledge cryptography generates proofs on the user’s device and leaves the chain to verify only that a valid proof exists. The first asset on the framework was strkBTC after Starknet’s v0.14.2 protocol upgrade in April 2026, with USDC support added on June 25, 2026. Starknet said any ERC-20 token on the network can integrate without separate liquidity, and launch wallet support includes Xverse, AVNU and Circle integrations. The framework also includes encrypted viewing keys, letting users selectively share transaction history with auditors, regulators or legal counterparties, while third-party auditors can hold those keys so a court order or compliance request can reveal one user’s records without exposing others. The rollout followed privacy-related feature introductions in March 2026, a full privacy engine implementation in April 2026 and the June mainnet launch. Starknet has signaled that future phases will extend STRK20 to private lending products and cross-chain functionality.