Starknet activated STRK20 on mainnet on June 9, 2026, making zero-knowledge privacy a native feature of ERC-20 tokens on the network rather than an add-on service. Users can shield balances and conceal transaction amounts in a single click, swap privately through avnu, and lend or stake via Vesu and Endur, all from standard wallet flows in Ready X or Xverse. Proofs run on Stwo, Starknet's own ZK system; shielding costs 4 STRK per transaction.
Viewing keys, not mixers
The compliance design separates STRK20 from mixer-style tools. Each participant registers an encrypted viewing key; when an authorized party presents a valid legal request, an independent auditor can use that key to reconstruct one account's full activity while all other accounts in the pool remain hidden. Damian Chen, VP of Growth at the Starknet Foundation, called it "practical privacy in the truest sense." Eli Ben-Sasson, CEO of StarkWare, said the mechanism could enable "more precise regulatory enforcement" than current approaches.
strkBTC first; private stablecoins next
strkBTC, a Bitcoin-backed ERC-20 on Starknet, was the first asset under the STRK20 standard, going live on May 12, 2026, four weeks before the Phase 1 rollout. Private stablecoins and institutional DeFi are the framework's stated next targets. The Block reported in March 2026 that the standard's priority use cases were privacy stablecoins, to shield users from front-running, and private corporate payments.
